dcmodels

I have read a number of posts that begin with an electrical system complaint, followed by a statement that the problem cannot be the battery, since it is *almost* new. But a new battery really can fail in only one or two years.
================================
Example of COSTCO KIRKLAND BATTERY GROUP 35:
The new battery was weak, and would not accept a full charge, even after daily driving and overnight (every-night) charging for a period of about 1-month. The battery was returned and exchanged for a second battery, which has been OK.
================================

So what can you do to ensure that your new battery will most likely last for the full warranty period? And how can you check that your existing battery is still healthy, and unlikely to suffer unexpected failure?

My DW and whack-a-doodle sister like to drive where Cell Phone service is not available, and where tow truck service is doubtful. Southwestern desert Anasazi ruins and cliff dwellings are a favorite destination. But even inside a large city, vehicular failure during very hot or cold weather, or a snow storm or in heavy summer city traffic, can be dangerous. Hypothermia or heat stroke is possible when the ambient is -10 or +110 degrees, and there is no shelter while waiting for the tow truck or emergency service to arrive on the scene. These are the reasons that I take extra measures to avoid vehicle failure. This post discusses the battery.

DANGER:
You should be wearing safety glasses or goggles when checking and connecting any charger to the battery, or doing anything with the battery. Remember, battery acid can cause blindness within a few seconds.

There are two basic problems that you face in purchasing a new battery. But the following information may help to ensure that your new battery is the best quality you can buy:

Ø READ THE BATTERY DATE CODE: that new battery may be as much as one year old already, partially sulfated, and very unlikely to last the full warranty period. Unless you read the date code(s) on the battery, there is no way to know how long the battery has been sitting on the shelf.

Ø CHECK THE BATTERY FOR DEFECTS BEFORE INSTALLATION: that new battery may be one that was not caught by the manufacturer’s Quality Control check.

ADDITIONAL INFORMATION:
LINK: how to care for your battery, plus trickle charger (and battery de-sulfate) review
https://acurazine.com/forums/showthread.php?t=775689

LINK: how to battery date codes
https://acurazine.com/forums/showthread.php?t=775691


BUYING A RECOMMENDED BATTERY:
The Group 35 battery that I purchased from CostCo, for my 2009 RDX was rated as a BEST BUY in the Nov 2012 issue of Consumer Reports, and fourth in quality, out of 9 recommended batteries. The July 2013 issue of Consumer Reports did *not* rate this same battery as a recommended-to-buy, and certainly not a best buy. So, in only 6 months, this particular battery went from *best-buy* to *not-recommended* status. Also, in the July issue only two Group 35 batteries were rated RECOMMENDED, only one of which was the same as in the list of 9 recommended batteries in the Nov 2012 issue.

That may explain the problems that I had with the CostCo battery that I purchased. Perhaps CostCo changed supplier/ manufacturer, or perhaps the manufacturer lowered the quality of its battery. Who knows? And that is the reason why you should learn how to test/ check any new battery that you purchase, before it is installed.

Also, the price of the CostCo battery that I purchased was listed as $60 by Consumer Reports, but my actual cost was $72, still a relative bargain for a good battery.

DATE CODE: what is on the battery?
When a battery sits on the retail shelf for 6-months, it deteriorates, and may never regain its full potential service life. Any car battery, any brand, when allowed to sit for an extended period of time, without being kept fully charged, will absolutely deteriorate (sulfate and lose charge-level).

There can be as many as 3-4 different date codes on a battery:

Ø Manufacture – the date that the battery was assembled at the factory.

Ø Inventory – the date the battery was placed into the manufacturer’s inventory.

Ø Ship – the date that the battery was shipped to the retailer or distributor, from the factory.

Ø Warranty – the date used for warranty purposes, by the retailer, if you do not retain your sales-receipt.

Ø Purchase – the date that you purchase the battery, as marked on your sales-receipt, and the date used to warranty the battery when it fails. Obviously, this is the only date that is *not* marked on the battery.

DATE CODE: how to read it on your new battery:
The date codes on a battery vary by manufacturer. Please read my post on how to read date codes, in the link listed above. But basically, most batteries will use a single letter for the month: A – January, B – February, etc. and one or two digits for the year: 1 – 2011, 2 – 2012, 3 – 2013, etc.

For example, the CostCo Group 35 battery that I purchased had the following date codes:

Ø Manufacture – 3A24BN2D, which is 24 January 2013. This code is stamped (melted) into the battery case, on the front vertical edge of the top.

Ø Inventory – B31KU, which is February 2013. This code is stamped (melted) into the edge/ corner of the top of the battery.

Ø Ship – 2/13, which is February 2013, as stated on a sticker on the side of the battery case.

Ø Warranty – 2/13, which is February 2013. This date is on an orange round sticker on the top of the battery. Yes, its just a sticker which could be added at any time after manufacture of the battery.

Ø Purchase – 14 Mar 2013, the date on my sales-receipt. This date is *not* on the battery.

As another example, the AC Delco battery that was replaced in my Chevy, had a MANUFACTURED DATE stamped on the battery case, that was 5 months older than the WARRANTY DATE on the paper label.

VOLTAGE TEST: how much voltage should a new battery read?
Generally, a fully charged new battery should have an open-circuit reading of 12.65 volts at 80 degrees Fahrenheit. However, reading the voltage of a battery is useful only to compare your fully charged reading against another later reading, to determine if the battery requires re-charging.

Digital Voltmeter Open
Circuit Voltage ......... Approximate State-of-Charge
========================= ===========================
12.65 ................... 100%
12.45 ................... 75%
12.24 ................... 50%
12.06 ................... 25%
11.89 ................... Discharged

There are some very important reasons for the above statements:

Ø A voltage reading is valid *only* if the battery has been *resting* for 12 hours, without starting the car or any other use of the battery (no lights, radio, etc.).

Ø The specific voltage of a fully charged battery, depends upon both the brand and type of battery. A fully charged AGM-type battery voltage is generally (slightly) higher than the voltage of a lead-type wet-cell battery.

Ø The DCVM digital volt-meter that is used should be accurate to 0.5% or better. That will give a meter reading of between 12.59v and 12.71v, for an actual voltage of 12.65v.

Ø For example, the DCVM that I am using is only accurate to 1.2% so that a meter reading of between 12.50v and 12.80v will be given, for an actual voltage of 12.65v, which is not accurate enough to be useful for an absolute reading. I only use my DCVM for *relative* readings, to compare my fully charged battery reading, against a later reading, to determine when the battery needs to be re-charged.

Ø When you measure the voltage of the battery in your car, it is never going to be an *open-circuit* voltage. Open-circuit means that the battery is not connected to anything. Modern cars always have some circuit *active*, even when the ignition switch is OFF. That is called a parasitic load. Yes, even that very small load (current-draw), will cause the battery to read slightly less than if there were no load at all on the battery (open-circuit), that is, battery removed from the car.

VOLTAGE TEST: table by battery temperature
The following table indicates how the battery voltage is affected by electrolyte (battery acid) temperature. This is exactly why a cold battery, when the ambient is below freezing, has more trouble starting your car. And why people in cold climes use a battery heater blanket overnight.

Notice that when a fully charged battery is at zero degrees, that it has only about 80-85% of the voltage (and starting power), that it has at 80 degrees.

Electrolyte ... Electrolyte ... Add or Subtract ... Actual Voltmeter's
Temperature ... Temperature ... to Digital ........ Reading
Degrees ....... Degrees ....... Voltmeter's
Fahrenheit .... Celsius ....... Reading
=============== =============== =================== ==================
120° .......... 48.9° ......... -.0129 ............ 12.663
100° .......... 37.8° ......... -.0084 ............ 12.658
80° ........... 26.7° ......... 0 ................. 12.650
60° ........... 15.6° ......... +.0158 ............ 12.634
40° ........... 4.4° .......... +.0435 ............ 12.606
20° ........... -6.7° ......... +.0843 ............ 12.566
0° ............ -17.8° ........ +.1335 ............ 12.516

VOLTAGE TEST: what did my new CostCo battery read?
To obtain a valid voltage reading on your RDX battery, you must open the hood, close the doors, and leave the vehicle overnight at least 12 hours. If you open the doors of the RDX, to release the hood latch, just before taking the voltage reading, the battery will read *low*. This is because even if the inside overhead lights are not on, the dash lights are on. And even if you then close the doors, and the dash lights go off, the battery will still read low. Again, the battery must sit for 12 hours without any load other than the parasitic load of the computers.

FIRST BATTERY – weak and would not take a full charge (exchanged for a second battery)
The battery that I purchased for my RDX from CostCo, was the Kirkland Signature #3 reference number, p/n 12865, Group 35 (size), 640 CCA (cold cranking amps).

PURCHASE DATE: 31 Jan 2013
MANUFACTURE DATE: 2M16AA2C, which is 16 Dec 2012
INVENTORY DATE: was not noted
SHIP DATE: 12/12, which is December 2012
WARRANTY DATE: 1/13, which is January 2013

VOLTAGE READING: 12.50v @ 44 degrees
That reading was taken with my DCVM, which is only 1.2% accurate. That reading was taken 1-month after installation, and after charging for about 100 hours, in the vehicle, with a de-sulfating trickle charger.

I did not consider that this was an acceptably high voltage reading, compared with the voltage reading of the fully charged OEM Acura battery which was replaced after almost 4-years. The OEM battery consistently read 12.6 volts, up until a couple of months before it was replaced, when fully charged.

So this first CostCo Kirkland battery was returned, and exchanged for another one. As a CostCo member, the battery exchange was made without any further cost or question or battery test. I simply showed my receipt, and received a new battery in exchange. It is difficult to beat a warranty like that, and there are CostCo stores in a lot of cities.

SECOND BATTERY – good but slightly discharged when purchased
The replacement battery was the same as the first battery, as follows:

PURCHASE DATE: 14 Mar 2013 (actually the exchange date)
MANUFACTURE DATE: 3A24BN2D, which is 24 Jan 2013
INVENTORY DATE: B31KU, which is February 2013
SHIP DATE: 2/13, which is February 2013
WARRANTY DATE: 2/13, which is February 2013

VOLTAGE READING: 12.60v @ 50 degrees
That reading was taken with my DCVM, which is only 1.2% accurate. That reading was taken 3-days after installation, and after charging the battery, in the vehicle, with a de-sulfating trickle charger.

The voltage reading taken immediately after purchase, and just before installation, was 12.56v at 74 degrees. That is a true open circuit reading. Immediately after installation in the vehicle, the voltage was 12.52v. The difference is because of the parasitic current draw (load).

Voltage readings in June 2013 at 84 degrees, are about 12.67v, taken with the same DCVM as all other readings reported in this post, after about 50 hours on a trickle-charger, and two 2000 miles road trips.

Do note that this RDX is driven primarily on short city trips, and not every day, and that after 1-week the usual voltage reading is 12.54v. Therefore, the battery is connected overnight one-day-per-week to a trickle charger.

VOLTAGE TEST: how well does the new CostCo battery hold a charge?
Unless the vehicle is driven daily, for at least 10 miles without stopping, any battery will slowly discharge and sulfate, and finally die. The only other option is to occasionally use a trickle charger.

The following is a typical discharge rate for the CostCo battery, after being fully charged, and in typical use for this vehicle:

12.60v @50 degrees .. 17 Mar .. 1-day
12.56v @48 degrees .. 18 Mar .. 2-days
12.54v @48 degrees .. 19 Mar .. 3-days
12.54v @42 degrees .. 23 Mar .. 6-days

The CostCo battery compares similarly to the PepBoys battery in my Chevy, both in terms of the discharge rate under similar driving conditions (short trips or sitting), as well as the voltage level to which the battery falls after 1-week. And yes, the Chevy battery is placed on a trickle-charger, once every week or two, to keep it from sulfating.

VOLTAGE TEST: how well does the RDX charging system work?
It’s the “smart” (dumb?) electronically-controlled small output 100amp alternator, the myriad of electronic gadgets in the car, as well as the ELD (electrical load detection) device – which limits alternator output to *save-gas*, while allowing the battery to discharge.

I will post a later thread on the ELD device, if you have no idea of what it is, or did not know there is one in your RDX. I was unaware of its existence, until after a discussion with the service manager at my local Acura dealer.

According to multiple complaints on this forum, the RDX does not keep its battery charged. This is normally blamed on the OEM battery. But really, if the RDX cannot keep a 440 cca OEM battery at full charge, what hope is there to keep a replacement 640 cca battery fully charged? True, the higher-amp battery will hold enough charge to start your car, for a longer period, useful when parking at the airport lot.

But really, this is not rocket science. If the RDX alternator cannot fully charge a low amp-hour battery, how can it possibly fully charge a battery that is *50-percent-larger*. If the vehicle is driven on many short trips, any battery is simply going to slowly discharge.

VOLTAGE TEST: conclusions
A new battery, even a manufacturer brand and model recommended by Consumer Reports, can be defective. No manufacturer has 100% quality control. Besides, I have no idea how the manufacturer even checks its batteries.

Also, the quality of a particular battery manufacturer, and a particular battery model, can change within only 6-months – at least as reported by Consumer Reports. Such a change does not give me a great deal of confidence in that brand of battery.

A new battery, even one that is less than 2-months old from the manufacturer date, will not be fully charged. So you can either jump on the freeway, and drive at least 30 minutes, or you need to put that battery on a trickle-charger. And if the battery is 3-6 months old, unless it is immediately charged after purchase, either before or immediately after installation, it will never achieve its potential service life. If that is too much trouble, hey, its your money and your time.

HYDROMETER TEST: what should a new battery read?
A fully charged battery acid (electrolyte) should read 1.265 density at 80 degrees. Again, this can vary slightly, depending upon both brand and type of battery. And the reading is affected by ambient (battery acid) temperature, just like voltage. But I am not going to include a temperature correction table for hydrometer readings – just do yourself a favor and use a temperature-compensating hydrometer.

NOTE: just as for voltage readings, valid hydrometer readings can only be taken after the battery has been sitting for 12 hours, without the engine being started, or any other load (such as dash lights) being placed on the battery. That means, you must prop open the hood, and leave the car doors closed for 12 hours.

Yes, the voltage readings in the table below differ slightly from those in the voltage table in one of the sections above. The difference is minor, and worth listing, just to illustrate that minor differences do not matter. What matters is the relative measurements that you take of your own battery, with your own DCVM and hydrometer.

Regardless of the table below, do note that the RDX probably will not start if the battery hydrometer reading is much below 1.250 because of the particular engine setup (low compression, turbo, and variable cam-timing). There is a reason why my 15 year old Chevy V6 *always* starts in less than 1-second, while my RDX consistently takes 2-3 seconds to start. And it is not the battery.

The RDX 640 cca replacement battery does not start the engine any easier (faster) than the OEM 440 cca original battery. And just as a comparison, the OEM battery in my ’98 Chevy was 525 cca.

The extra effort (length of time) required to start the RDX is an extra load on the battery, which means it takes longer to recover the battery charge-level after every engine start, than if the engine start time were shorter.

State-of-Charge ... voltage ... specific gravity
=================== =========== ================
100% .............. 12.70 ..... 1.265
90% ............... 12.58 ..... 1.249
80% ............... 12.46 ..... 1.233
70% ............... 12.36 ..... 1.218
60% ............... 12.28 ..... 1.204
50% ............... 12.20 ..... 1.190
40% ............... 12.12 ..... 1.176
Discharged ........ 11.90 ..... 1.120

HYDROMETER TEST: what did my new CostCo battery read?
I used a temperature compensating hydrometer to measure the electrolyte (battery acid) specific gravity in the new CostCo battery. The measurements shown here are for the second CostCo battery, the one I kept, not the first one which I deemed defective, and returned.

These first measurements were taken on the day of purchase, 14 Mar 2013, just prior to installation into the vehicle, as a reference. Note that the readings are slightly low for a new battery, consistent with the initial low voltage reading at time of installation, as discussed in a section above. Again, this is an indication that a new battery less than 2-months old, has already started to discharge from sitting.

The six readings are for the six cells, left-to-right, from the positive post to the negative post:
58 .. 57 .. 58 .. 57 .. 56 .. 56

Readings were taken at 74 degrees, with a corresponding voltage of 12.56v – Note that 58 really means 1.258, and 57 means 1.257, etc.

====================
About two weeks later, a second set of readings were taken, and the water level was topped up in each cell. Every cell but one required a minor amount of distilled water to be added. The second set of readings were:
65 .. 65 .. 67 .. 67 .. 63 .. 63

Readings were taken at 48 degrees, with a corresponding voltage of 12.54v, down from the reading of 12.60v taken 3 days after battery installation – yes, this voltage is somewhat lower than a fully charged battery would show. The lower voltage reading is mostly because of the lower temperature – the reading is not adjusted for temperature. And because the vehicle had been driven only on short trips during the first two weeks after the battery was installed. Short trips in an RDX will slowly discharge the battery, in only one week.

See the section above on voltage readings, which show that this battery eventually was fully charged to 12.67 volts. I did not take another set of hydrometer readings, corresponding to the 12.67v reading, taken in June 2013. The voltage reading tells me that the battery is fully charged, and therefore, there is no reason to take additional hydrometer readings. After all, the purpose of taking voltage readings, and comparing them to earlier readings, is to avoid the time consuming task of taking hydrometer readings.

The only reason to check the hydrometer readings is to also check the water level, and to verify that there is no weak cell. A hydrometer test is the only way to check the charge-level of each cell individually.

A hydrometer test can be limited to only once or twice per year, depending upon the battery type and weather conditions. Very hot weather will cause the water to evaporate from any non-maintenance-free type battery. I have owned batteries that required no water to be added even after 5 years.

But the OEM RDX battery required some water to be added every spring and fall. This may be another reason for complaints about the OEM RDX battery. Unless a battery is kept topped up with water, it will eventually short-circuit and fail.

HYDROMETER TEST: conclusions
A new battery can be defective, with a single weak cell. Only a hydrometer test can determine this. A voltage test is probably not accurate enough, unless one cell is actually shorted. A shorted cell will typically cause a voltage reading of less than 11.00 volts.

A new battery can be partially discharged, and low on water, when purchased. But water should *only* be added after charging the battery to full-charge-level. Yes, the water level will increase as the battery is charged.

To ensure that a new battery will last for its full potential service life, it should be charged with a trickle charger to full charge level, either before installation, or immediately after vehicle installation. Or the vehicle should be driven at least 30 minutes, and preferably for 1-hour at freeway speeds, to fully charge the battery.

LOAD TEST: what does it test, and how does it work?
The Load Test is considered the Gold Standard of battery health. It can tell you if the battery definitely requires replacement. But, the test is not so accurate in determining the difference between a battery that is only Fair, and one that is Good or Excellent. The test results are subject to machine operator (mis)-interpretation, unless one of the multi-thousand dollar-cost machines is used.

Simplistically, a Load Test will determine if your battery can start your car at 0 (zero) degrees. The load test machine does this by applying a current load similar to that from the engine starter, specifically one-half of the rated CCA of the current battery, for 15-seconds. Or use one-half of the OEM battery CCA, whichever is greater.

During the load test, the voltage level of the battery should not drop below the following table’s indicated voltage for the electrolyte (battery acid) at the temperatures shown:

Electrolyte ..... Electrolyte ..... Minimum Voltage Under
Temperature F ... Temperature C ... LOAD
================= ================= =====================
100° ............ 37.8° ........... 9.9
80° ............. 26.7° ........... 9.7
60° ............. 15.6° ........... 9.5
40° ............. 4.4° ............ 9.3
20° ............. -6.7° ........... 8.9
0° .............. -17.8° .......... 8.5

Remove the load, and wait 10 minutes. Then check the State-of-Charge against one of the tables above, using either a voltage or a hydrometer test. If the SOC does not recover to at least 75% of a full charge level, then replace the battery, because it does not have sufficient CCA capacity.

The above procedure will be performed automatically by some Load Testers. The problem is that a Load Test machine can vary in price, from $50 to over $5,000 with valid-operation relative to the price of the machine.

The basic problem is that the cheaper machines are subject to operator misuse, or improper interpretation of the results, if the operator is either ignorant or dishonest. Keep this in mind, as most auto parts places will be using one of the cheaper machines. And I have had more than one place tell me that my perfectly good battery, as tested by myself, required replacement.

Now I only have a load test performed in order to confirm the results of my own tests. And I only trust the results from one of the more expensive machines, as used by my local Acura dealer, or a Sears location which uses one of the multi-thousand dollar machines.

LOAD TEST: perform your own test
I would recommend against purchasing your own Load Test Machine, unless you are willing to spend at least $400-500, because the test results will not be accurate enough, in my opinion.

However, you can perform your own very simple load test, that will give you a general idea of the battery health. I purchased a plug-in battery voltage monitor from Wal-Mart, Everstart Battery Monitor Voltmeter p/n 932W.

Plug-in the battery monitor to the accessory port on the center dash, and start your RDX. Check the lowest voltage level displayed by the monitor during engine starting. You need a *quick-eye* to see the lowest voltage reading during engine starting. Compare your reading against one of the voltage tables above. But in my opinion, if the voltage falls below 9.5v regardless of the ambient outside temperature, the battery either need re-charging or requires replacement.

LOAD TEST: by my local Acura dealer
My Acura dealer has two load test machines: one that probably cost a few hundred dollars, and one that cost several thousand dollars. I have never had them use the more expensive machine, which is fully automated and performs a test of the entire charging system as well as the battery – because the test by that machine takes 30 minutes and the dealer charge/ cost for the test, is close to the cost of a new battery.

My Acura dealer has always tested my RDX batteries using the less expensive load test machine, for free, each time that I bring in my car for service. When used properly, the results are fairly accurate, mostly because I trust the techs at my Acura dealer.

To more severely load the battery, and to remove the surface charge before performing the load test, the Acura tech will sometimes turn on the hi-beam headlights for 5 minutes, without the engine running. Believe me, if the battery is weak then it will fail the following load test. And sometimes, if the first load test results are inconclusive, this procedure is repeated. Any weak battery will definitely fail the second load test.

The Acura dealer is happy to perform a load test for free, simply because if the battery fails the test, then the car engine probably will not start, and in order leave the dealership, the car owner has to purchase a new battery. Well, I suppose that is fair for a free test

LOAD TEST: what did my own RDX batteries read?
The following tests were performed at my local Acura dealer, using a handheld machine that probably cost a few hundred dollars. The first test results here are from the 4-year old OEM Acura battery, delivered in my car when purchased new. The results are given to show how a four year old battery can still test good, when kept fully charged during its service life.

RATING: 440 CCA ... manufactured Nov 2008
DATE: 08/04/09 ... 589 CCA ... 12.93v
DATE: 02/18/11 ... 481 CCA ... 12.51v
DATE: 08/25/11 ... 500 CCA ... 12.57v
DATE: 01/04/13 ... 431 CCA ... 12.61v ... 3:21 pm
DATE: 01/04/13 ... 426 CCA ... 12.53v ... 3:25 pm
DATE: 01/04/13 ... 417 CCA ... 12.57v ... 3:30 pm

The last 3 tests were performed on the same day, as shown above, because I had difficulty believing that the battery was still good after 4-years. So why did I replace this battery less than a month later? Because the RDX trunk lights were left on for a couple of days, completely draining the battery. Apparently the hatch light does not automatically turn off after a certain time period. Perhaps the battery could have been re-charged, but the local temperature had not been above 30 degrees for two months, and I just decided to buy a new battery rather than mess with it.

==============
The following test result is for the first CostCo Group 35 battery that I purchased, the one that I decided was defective and returned for an exchange. The result below is actually from the third of three back-to-back tests. The first two test results were only slightly higher, than the third. Unfortunately, I do not have a copy of those results, so cannot include them here.

RATING: 640 CCA ... manufactured Dec 2012
DATE: 02/28/13 ... 721 CCA ... 12.59v

I was curious how the test machine actually worked, so the tech obliged by performing the test 3-times, at different CCA load-levels. I expected 3 different results, but they were basically the same. I am thinking that testing at different CCA levels should have produced significantly different results. This is one of the reasons why I have doubts about the absolute accuracy of that particular test machine.

And by-the-way, I do not recommend multiple load-tests on a battery, within a short time. If the battery is not allowed a short ‘rest’ between tests, its service life can be shortened (permanently). Even so, multiple load tests are very hard on a battery.

LOAD TEST: conclusions
But wait, some of you must be saying. The test results just above would seem to indicate that the first CostCo battery that I purchased, did not need replacement. There were some basic reasons why I replaced this battery anyway:

Ø I believe that my own test results of the SOC for this first replacement battery, with my own equipment, by voltage and hydrometer readings, were *NOT* as high as a brand new (excellent) battery should be. My own SOC readings of the second replacement CostCo battery, which were significantly higher, seem to confirm this.

Ø I do not believe that the test results from the dealer’s Acura Load Test machine, which produced the results above, are sufficiently accurate to determine the difference between a battery that is EXCELLENT (new), and one that is only GOOD.

Ø Does anyone believe that the OEM Acura battery will really test and deliver a higher CCA than its rated CCA? Check the readings again, above, for my own OEM RDX battery. I do not know if the problem is the machine, or the operator, but there is definitely a problem with the test result readings, in my opinion.

Ø I do believe that the Load Test machine used by my Acura dealer, in the tests above, can determine if the battery is BAD, and requires replacement. Remember, that test machine was the less expensive, general purpose machine, not the fully automated Acura Load Test machine.

Ø I do not know just how accurate the very expensive, multi-thousand dollar Load Test machines, really are. I have directly observed the use of such a machine at a local Sears Automotive store. At best, I can only say that it did correctly indicate a problem with a weak battery in my Chevy V6. But really, I was already aware that the Chevy battery was having trouble starting the engine in very cold weather. So, the Sears load test only confirmed what I already suspected.

-----eof

swoosh

iTrader: (5)

I need to come back and read

























the remaining post....hella long - but - informative post...

dcmodels

How to Buy a GOOD Battery - Bosch example

When you have an electrical (or any type of) problem with your car, are you certain that your battery is OK? Before diagnosing any electrical problem, you must ensure that the battery is *good* and fully charged – else you are wasting your time.

It will take you longer to read this post, than to check your own battery health (old or new), with an inexpensive DCVM (digital DC voltmeter) and a $10 temperature compensated Hydrometer.

So what can you do to ensure that your new battery will most likely last for the full warranty period?

Ø READ THE BATTERY DATE CODE: that new battery may be as much as one year old already, 80-90% low on charge, partially sulfated, and very unlikely to last the full warranty period. Unless you read the date code(s) on the battery, there is no way to know how long it has been sitting on the shelf.

Ø CHECK THE BATTERY FOR DEFECTS BEFORE INSTALLATION: that new battery may be one that was not caught by the manufacturer’s Quality Control check. That is why there are battery warranties.

DANGER:
You should be wearing safety glasses or goggles when checking and connecting any charger to the battery, or doing anything with the battery. Remember, battery acid can cause blindness within a few seconds.

================================
Example of BOSCH Premium Power 75-730B 3-year BATTERY GROUP 75:
The new battery had a bad cell, not shorted, but completely discharged. The battery was returned and exchanged for a second battery, which was OK, although slightly discharged. I charged the second battery with a trickle charger before installation. When I had the time, and before I purchased my own charger, I have always asked SEARS to slow charge my newly purchased DieHard battery overnight, before I installed it – yes, prefer to do my own install rather than have Sears do it.

Example of AC Delco Professional 75-7yr BATTERY GROUP 75:
The new battery was 1-year old, from date of manufacturer, when I purchased it from my Chevy dealer, in Dec 2008. It was actually manufactured in January 2008, but the paper label said it was made in May 2008. So the manufacturer did not ship the battery until 5-months after it was made. And the Chevy dealer had it in stock for another 7-months.

But it could have been worse. While looking through the available Chevy dealer battery stock, I found one battery that was almost 2-years old. I guess that either the parts guy does not know how to read the date codes, or does not care enough to pull the oldest stock first when selling a battery. A car dealer is not the best place to buy a battery – unless you are desperate – and I was.

So unless you know how to read the date codes, you may be buying a battery that has been sitting on the shelf for 1-year or more. And a battery that has been sitting for that long, is unlikely to last its full warranty period.

WHY YOU NEED THE BEST BATTERY POSSIBLE:
A battery that is simply low in charge (weak), can cause intermittent and strange problems. In modern cars, the electrical circuits are controlled & completed, by computers (chips). Remember, nothing is directly controlled by the dash selection buttons, or the automatic-transmission selector.

You make your operational selections by pressing tiny buttons, and the computers decide if your selection will actually be allowed. Then the required electrical power is switched by relays, and supplied through fuses. So if the battery is low, slightly discharged, then the voltage drops, and things just do not work correctly.

Any time there is an electrical problem, check first for loose battery cables. And then check that the battery is in good *health*. To check battery cables, just gently try to rotate each cable-end at the battery post-connection. I once had a Chevy service writer pull on my perfectly tight cables so hard, that the side-posts of the battery were damaged, then told me the cables were loose – and yes, at that point, they were L

POSSIBLE SYMPTOMS of a WEAK BATTERY: here are some real problems, as reported in various forum complaints, such as flickering dash lights and non-logical error codes (DTC – data trouble code). This is hardly a complete list:

Ø Mal-functioning gauges: there may be nothing wrong with the dash electrical circuits, but the trip meter may reset, or the gauges may not read correctly

Ø NAV system: low-voltage message

Ø HVAC (heater, vacuum, A/C): random mal-functions, vent-doors do not move, or do not move correctly, so that the correct temperature is not provided (too hot or cold)

Ø Exhaust: O2 sensor DTCs

Ø Transmission: rough shifting and DTCs for the pressure switches or control solenoids

Ø 4-wheel drive: depends on your particular vehicle, but 4x4 systems with an electrically selected transfer case may mal-function, or report DTCs

ADDITIONAL INFORMATION:
Search this forum and others, as well as online and you can find information about reading a battery date code, types of batteries, how to check your battery, battery chargers, load test machines, etc. – really just about anything to do with batteries. Just remember that any information you find, was posted on the internet, or may simply be an advertisement

BUYING A RECOMMENDED BATTERY:
The Group 75 battery that I purchased from PepBoys, for my 1998 Chevy S10 Blazer was rated as a BEST BUY in the Nov 2012 issue of Consumer Reports, and rated third in quality, out of 4 recommended batteries. The July 2013 issue of Consumer Reports did *not* rate this same battery as a recommended-to-buy, and certainly not a best buy. So, in only 9 months, this particular battery went from *best-buy* to *not-recommended* status.

That may explain the problems that I had with the Group 75 battery that I purchased. Perhaps PepBoys changed supplier/ manufacturer, or perhaps the manufacturer lowered the quality of its battery. Who knows? And that is the reason why you should learn how to test/ check any new battery that you purchase, before it is installed.

Also, the price of the PepBoys battery that I purchased was listed as $80 by Consumer Reports, but my actual cost was $110, minus 20% because of a special sale, still a relative bargain for a good battery.

DATE CODES: what is on the battery?
When a battery sits on the retail shelf for 6-months, it deteriorates, and may never regain its full potential service life. Any car battery, any brand, when allowed to sit for an extended period of time, without being kept fully charged, will absolutely deteriorate (sulfate and lose charge-level).

There can be as many as 3-4 different date codes on a battery:

Ø Manufacture – the date that the battery was assembled at the factory, melted into the battery case.

Ø Inventory – the date the battery was placed into the manufacturer’s inventory, melted into the battery top.

Ø Ship – the date that the battery was shipped to the retailer or distributor, from the factory, printed on a paper sticker on the battery case.

Ø Warranty – the date used for warranty purposes, by the retailer, if you do not retain your sales-receipt, printed on the label on the battery top, or on a separate sticker (usually round) on the battery top.

Ø Purchase – the date that you purchase the battery, as marked on your sales-receipt, and the date used to warranty the battery when it fails. Obviously, this is the only date that is *not* marked on the battery.

VOLTAGE TEST: how much voltage should a new battery read?
Generally, a fully charged new battery should have an open-circuit reading of 12.65 volts at 80 degrees Fahrenheit. However, reading the voltage of a battery is useful only to compare your fully charged reading against another later reading, to determine if the battery requires re-charging.

Digital Voltmeter Open .. Approximate
Circuit Voltage ......... State-of-Charge
========================= ===============
12.65 ................... 100%
12.45 ................... 75%
12.24 ................... 50%
12.06 ................... 25%
11.89 ................... Discharged

There are some very important reasons for the above statements:

Ø A voltage reading is valid *only* if the battery has been *resting* for 12 hours, without starting the car or any other use of the battery (no lights, radio, etc.).

Ø The specific voltage of a fully charged battery, depends upon both the brand and type of battery. A fully charged AGM-type battery voltage is generally (slightly) higher than the voltage of a lead-type wet-cell battery.

Ø The DCVM digital volt-meter that is used should be accurate to 0.5% or better. That will give a meter reading of between 12.59v and 12.71v, for an actual voltage of 12.65v.

Ø For example, the DCVM that I am using is only accurate to 1.2% so that a meter reading of between 12.50v and 12.80v will be given, for an actual voltage of 12.65v, which is not accurate enough to be useful for an absolute reading. I only use my DCVM for *relative* readings, to compare my fully charged battery reading, against a later reading, to determine when the battery needs to be re-charged.

Ø When you measure the voltage of the battery in your car, it is never going to be an *open-circuit* voltage. Open-circuit means that the battery is not connected to anything. Modern cars always have some circuit *active*, even when the ignition switch is OFF. That is called a parasitic load. Yes, even that very small load (current-draw), will cause the battery to read slightly less than if there were no load at all on the battery (open-circuit), that is, battery removed from the car.

VOLTAGE TEST: table by temperature
The following table indicates how the battery voltage is affected by temperature. This is exactly why a cold battery, when the ambient is below freezing, has more trouble starting your car. Notice that when a fully charged battery is at zero degrees, that it has only about 80-85% of the voltage that it has at 80 degrees.

Electrolyte ... Electrolyte ... Add or Subtract ... Actual
Temperature ... Temperature ... to Digital ........ Voltmeter's
Degrees ....... Degrees ....... Voltmeter's ....... Reading
Fahrenheit .... Celsius ....... Reading
=============== =============== =================== ==================
120° .......... 48.9° ......... -.0129 ............ 12.663
100° .......... 37.8° ......... -.0084 ............ 12.658
80° ........... 26.7° ......... 0 ................. 12.650
60° ........... 15.6° ......... +.0158 ............ 12.634
40° ........... 4.4° .......... +.0435 ............ 12.606
20° ........... -6.7° ......... +.0843 ............ 12.566
0° ............ -17.8° ........ +.1335 ............ 12.516

VOLTAGE TEST: what did my new PEP BOYS battery read?
To obtain a valid voltage reading on your S-10 battery, you must open the hood, close the doors, and leave the vehicle overnight at least 12 hours. If you open the doors of the S-10, to release the hood latch, just before taking the voltage reading, use the door key-lock, and the overhead light switch must *already* be in the OVERRIDE position (lights OFF).

Otherwise, the battery will read a *low* voltage. This is because if the overhead lights are on, and even if you then close the doors, and the overhead lights go off, the battery will still read low. Again, the battery must sit for 12 hours without any load other than the parasitic load of the computers.
==========

Pep Boys FIRST BATTERY – one cell was completely discharged (exchanged for a second battery)
The battery that I purchased for my S-10 from Pep Boys, was the Bosch Premium Power, Group 75 (size), 700 CCA (cold cranking amps). The part number 75T730XOW SA2 was melted into the battery. Serial number S09A3A2 0026 was melted on the case.

PURCHASE DATE: 09 Mar 2013
MANUFACTURE DATE: SA4 JAN1013, which is 10 Jan 2013, melted onto the case
INVENTORY DATE: Jan 2013 on a paper sticker
SHIP DATE: Feb 2013, on a paper label on the side of the battery
WARRANTY DATE: B-13, which is February 2013, on a round sticker on the side of the battery

VOLTAGE READING: 12.55v @ 70 degrees – yes even with one dead cell
Note that reading was taken with my DCVM, which is only 1.2% accurate. That reading was taken immediately after purchase at home, before installation. That reading is low for a new battery, so I performed a hydrometer test, which the battery failed.

Pep Boys exchanged the battery, without any paper work, because it was never installed in my vehicle. However, they performed a load test on the battery, to confirm that it was *bad*.
============

Pep Boys SECOND BATTERY – good but slightly discharged when purchased
The replacement battery was the same as the first battery. Serial number S09A3A2 0596 was melted on the battery case:

PURCHASE DATE: 09 Mar 2013
MANUFACTURE DATE: SA4 JAN1113, which is 11 Jan 2013, melted onto the case
INVENTORY DATE: Jan 2013 on a paper sticker
SHIP DATE: Feb 2013, on a paper label on the side of the battery
WARRANTY DATE: B-13, which is February 2013, on a round sticker on the side of the battery

VOLTAGE READING: 12.62v @ 70 degrees
That reading was taken immediately after the purchase, in the store, with the Pep Boys load test machine.

VOLTAGE READING: 12.58v @ 53 degrees
That reading was taken with my DCVM, which is only 1.2% accurate. That reading was taken on the purchase date, after I returned home with the new battery.

The voltage reading taken after trickle-charging the battery for 1-week, and *resting* overnight, and just before installation, on 16 Mar 2013, was 12.85v at 62 degrees. That is a true open circuit reading. Immediately after installation in the vehicle, the voltage was 12.77v. The difference is because of the parasitic current draw (load).

Do note that this S-10 is driven primarily on short city trips, and not every day, and that after 1-week the usual voltage reading is 12.54v. Therefore, the battery is connected most weekends to a trickle charger, unless it will be driven.
===========

AC Delco OLD BATTERY – the battery replaced with the Pep Boy battery
This battery was purchased from my local Chevy dealer, an AC Delco Professional 75-7yr group 75 (size), 700 CCA (cold cranking amps).

PURCHASE DATE: Dec 2008
MANUFACTURE DATE: 8A02AHRK, which is 02 Jan 2008, melted onto the case
INVENTORY DATE: was not marked on the battery
SHIP DATE: P058R, which is May 2008, on a paper label on the top of the battery
WARRANTY DATE: 5/08, which is May 2008, on a round sticker on the side of the battery

Note that at the time of installation in my vehicle, the battery was already 1-year old. Nonetheless, it lasted 4 more years after installation in my S-10, so its true life was 5-years. Pep Boys says that average battery service life in my location is 38 months. Its not the cold winters, but the seriously hot summers, that kill batteries.

During the last year of its service, the AC Delco battery spent most of its time on a trickle charger. It survived many abuses, including complete discharge by a failed (shorted) blower motor controller, 1-year before replacement.

VOLTAGE TEST: conclusions
A new battery, even a manufacturer brand and model recommended by Consumer Reports, can be defective. No manufacturer has 100% quality control. Besides, I have no idea how the manufacturer even checks its batteries.

Also, the quality of a particular battery manufacturer, and a particular battery model, can change within only 6-months – at least as reported by Consumer Reports. Such a change does not give me a great deal of confidence in that brand of battery.

A new battery, even one that is less than 2-months old from the manufacturer date, will not be fully charged. So you can either jump on the freeway, and drive at least 30 minutes, or you need to put that battery on a trickle-charger. And if the battery is 3-6 months old, unless it is immediately charged after purchase, either before or immediately after installation, it will never achieve its potential service life. If that is too much trouble, hey, its your money and your time.

HYDROMETER TEST: what should a new battery read?
A fully charged battery acid (electrolyte) should read 1.265 density at 80 degrees. Again, this can vary slightly, depending upon both brand and type of battery. And the reading is affected by ambient (battery acid) temperature, just like voltage. But I am not going to include a temperature correction table for hydrometer readings – just do yourself a favor and use a temperature-compensating hydrometer.

NOTE: just as for voltage readings, valid hydrometer readings can only be taken after the battery has been sitting for 12 hours, without the engine being started, or any other load (such as dash lights) being placed on the battery. That means, you must prop open the hood, and leave the car doors closed for 12 hours.

Yes, the voltage readings in the table below differ slightly from those in the voltage table in one of the sections above. The difference is minor, and worth listing, just to illustrate that minor differences do not matter. What matters is the relative measurements that you take of your own battery, with your own DCVM and hydrometer.

State-of-Charge ... voltage ... specific gravity
=================== =========== ================
100% .............. 12.70 ..... 1.265
90% ............... 12.58 ..... 1.249
80% ............... 12.46 ..... 1.233
70% ............... 12.36 ..... 1.218
60% ............... 12.28 ..... 1.204
50% ............... 12.20 ..... 1.190
40% ............... 12.12 ..... 1.176
Discharged ........ 11.90 ..... 1.120

HYDROMETER TEST: what did my new Pep Boys battery read?
I used a temperature compensating hydrometer to measure the electrolyte (battery acid) specific gravity in the new Pep Boys battery.

Pep Boys FIRST BATTERY – one cell was completely discharged (exchanged for a second battery)
These measurements were taken on the day of purchase, 09 Mar 2013, just prior to installation into the vehicle, as a reference. But because of the values, the battery was returned for exchange, and never installed.

The six readings are for the six cells, left-to-right, from the negative post to the positive post, with a corresponding voltage reading of 12.55v:

77 .. 75 .. 76 .. 77 .. 79 .. 10

Note that 77 really means 1.277, and 75 means 1.275, and 10 means 1.110 (not 1.210). Yes, that last cell was almost pure water. I was so stunned by the last reading, that I retested all 6 cells, 3 more times. I still have no idea what was wrong with the bad cell.
================

Pep Boys SECOND BATTERY – good but slightly discharged when purchased
These first measurements were taken on the day of purchase, 09 Mar 2013, as a reference. The six readings are for the six cells, left-to-right, from the negative post to the positive post, with a corresponding voltage reading of 12.58v @53 degrees:

56 .. 57 .. 60 .. 58 .. 60 .. 51

Note that 56 really means 1.256, and 57 means 1.257, etc. Yes, those readings are pretty low for a new battery, so the battery was then charged for 1-week.

These second readings were taken a week later on 16 Mar 2013, just before installing the battery in the vehicle, at a corresponding voltage reading of 12.85v @62 degrees.

66 .. 69 .. 70 .. 70 .. 70 .. 65

Immediately after installation in the vehicle, the voltage reading was 12.77v, the difference being the parasitic current draw of the S-10 computers, etc.
================

The reason to check the hydrometer readings is to verify that there is no weak cell, and also to check the water level. A hydrometer test is the only way to check the charge-level of each cell individually.

A hydrometer test can be limited to only once or twice per year, depending upon the battery type and weather conditions. Very hot weather will cause the water to evaporate from any non-maintenance-free type battery. The AC Delco battery required no water to be added during its entire service life, even after being completely discharged because of an electrical fault, and then recharged.

HYDROMETER TEST: conclusions
A new battery can be defective, with a single weak cell. Only a hydrometer test can determine this. A voltage test is probably not accurate enough, unless one cell is actually shorted. A shorted cell will typically cause a voltage reading of less than 11.00 volts.

A new battery can be partially discharged at an 80-90% level, and low on water, when purchased. But water should *only* be added after charging the battery to full-charge-level. Yes, the water level will increase as the battery is charged.

To ensure that a new battery will last for its full potential service life, it should be charged with a trickle charger to full charge level, either before installation, or immediately after vehicle installation. Or the vehicle should be driven at least 30 minutes, and preferably for 1-hour at freeway speeds, to fully charge the battery.

LOAD TEST: what does it test, and how?
The Load Test is considered the Gold Standard of battery health. It can tell you if the battery definitely requires replacement. But, the test is not so accurate in determining the difference between a battery that is only Fair, and one that is Good or Excellent. The test results are subject to machine operator interpretation, unless one of the multi-thousand dollar-cost machines is used.

Simplistically, a Load Test will determine if your battery can start your car at 0 (zero) degrees. The load test machine does this by applying a current load similar to that from the engine starter, specifically one-half of the rated CCA of the current battery, for 15-seconds. Or use one-half of the OEM battery CCA, whichever is greater.

During the load test, the voltage level of the battery should not drop below the following table’s indicated voltage for the electrolyte (battery acid) at the temperatures shown:

Electrolyte ..... Electrolyte ..... Minimum Voltage
Temperature F ... Temperature C ... Under LOAD
================= ================= ===============
100° ............ 37.8° ........... 9.9
80° ............. 26.7° ........... 9.7
60° ............. 15.6° ........... 9.5
40° ............. 4.4° ............ 9.3
20° ............. -6.7° ........... 8.9
0° .............. -17.8° .......... 8.5

Remove the load, and wait 10 minutes. Then check the State-of-Charge against one of the tables above, using either voltage or a hydrometer test. If the SOC does not recover to at least 75% of a full charge level, then replace the battery, because it does not have sufficient CCA capacity.

The above procedure will be performed automatically by some Load Testers. The problem is that a Load Test machine can vary in price, from $50 to $5,000 with accuracy-of-operation relative to the price of the machine.

The basic problem is that the cheaper machines are subject to operator misuse, or improper interpretation of the results, if the operator is either ignorant or dishonest. Keep this in mind, as most auto parts places will be using one of the cheaper machines. And I have had more than one place tell me that my perfectly good battery, as tested by myself, required replacement.

Now I only have a load test performed on my own batteries, in order to confirm the results of my own tests. And I only trust the results from one of the more expensive machines, as used by a Sears location which uses one of the multi-thousand dollar machines. No, I don’t trust the Sears operator/ tech, just their machine.

LOAD TEST: perform your own test
I would recommend against purchasing your own Load Test Machine, unless you are willing to spend at least $400-500, because the test results will not be accurate enough, in my opinion.

However, you can perform a very simple load test that will give you a general idea of the battery health. I purchased a plug-in battery voltage monitor from Wal-Mart, Everstart Battery Monitor Voltmeter p/n 932W.

Plug-in the battery monitor to the cigarette lighter in the ash-tray, on the center dash, and start your S-10. Check the lowest voltage level displayed by the monitor during engine starting. Compare your reading against one of the voltage tables above. But in my opinion, if the voltage falls below 9.5v regardless of the temperature, the battery either need re-charging or replacement. You need a *quick-eye* to see the lowest voltage reading during engine starting.

LOAD TEST: what did the Pep Boys batteries read?
The first Pep Boys Bosch battery that I purchased, was load tested to verify that it was indeed *bad*, and qualified for an exchange. The battery is clearly marked 700 cca on the label. But because of the part number 75-730B, the sales person insisted on testing at 730 cca with the load machine. I suppose I should not have argued, since testing at 730cca is a more severe test than at 700cca. Anyway, she actually tested twice, at both ratings.

She kept the printed copy, so I only wrote down some of the results, as follows:

RATING: 730 CCA ... manufactured 10 Jan 2013
DATE: 03/09/13 ... 650 CCA

The sales person insisted that this was a *good* result, and that the battery was OK. I knew that one cell was discharged, but she had no way to verify this. And the Load Test machine did not, nor could it, confirm this. But finally, she agreed to exchange the battery for a new one.
==============

The second replacement battery was also load tested, at my request, just so that I could compare the results against the test of the first battery. The sales person did not insist on that. The sales person was really quite polite, and I have never had any problem with Pep Boys purchases – just my own recommendation, after dealing with the chain for more than 40 years.

The following is from the printed results from the Load Test Machine at Pep Boys. The machine itself appeared to be completely automated, except for the operator input of the CCA rating of the battery. The machine appeared to be one of the more expensive, i.e., probably cost at least $1,000 or more.

RATING: 700 CCA ... manufactured 11 Jan 2013
DATE: 03/09/13 ... 709 CCA ... 12.62v
STATE OF HEALTH: GOOD/ 100%
STATE OF CHARGE: GOOD/ 80%

I admit that I am slightly confused by the printed machine results, particularly the STATE OF CHARGE. How can the STATE OF HEALTH be 100%, but the STATE OF CHARGE be only 80%? And what does that mean anyway? I can only assume that the 80% SOC is because of the voltage reading. That would be in line with my own reading of 12.85v after trickle-charging the battery for 1-week, versus the 12.62v reading above. But without access to the instructions for the load machine, I really cannot comment further on its operation.

If you do not have the time to wait on charging before battery installation, a good trickle charger will work fine after installation, if you charge the battery every night, for a couple of weeks.

LOAD TEST: conclusions
Feel free to draw your own conclusion, but the following are mine:

Ø I believe that my own test results of the SOC for the first replacement Pep Boys battery, with my own equipment, by voltage and hydrometer readings, clearly indicated that the battery was defective, regardless of what the Pep Boys load test machine indicated.

Ø I do not believe that the test results from the Pep Boys Load Test machine, which produced the results above, are sufficiently accurate to determine the difference between a battery that is EXCELLENT (new), and one that is only GOOD. Obviously, the Pep Boys sales person was never convinced that the first battery that I purchased, was really *bad*. Her opinion was that it was simply a bit low but still OK. This is exactly why you need to perform tests yourself, to determine if your battery is *good*.

Ø I do believe that the Load Test machine used by the Pep Boys store, in the tests above, can determine if the battery is BAD, and requires replacement. But as indicated above, the test results are subject to operator interpretation.

Ø I do not know just how accurate are the very expensive, multi-thousand dollar Load Test machines. I have directly observed the use of one such machine at a local Sears Automotive store. At best, I can only say that it did correctly indicate a problem with the weak AC Delco battery in my Chevy S-10 V6. But really, I was already aware that the Chevy battery was having trouble starting the engine in very cold weather. So, the Sears load test only confirmed what I already suspected.

---eof

jim_c

dcmodels - are you still there? I just read the whole thing.


What is your opinion on what makes one battery better than another?
How different are they internally? It seems to me (with no insider data at hand) that almost all batteries must be pretty similar if they use the same basic chemistry and the same basic materials. It's not a complex item, it doesn't have any moving parts, etc. And I am very interested in your opinion of Acura's own branded batteries. Many people criticize them and say they are cheap or low quality, but why would Acura do that? I would think they would want to put an excellent quality battery in their cars and not save a few pennies per unit using an inferior type.
Thanks for your contribution.

dcmodels

Quote:

Originally Posted by jim_c

dcmodels - are you still there? I just read the whole thing. ... Thanks for your contribution.

Thanks for reading, and here are my opinions concerning your questions. Batteries are actually quite complex systems, and for actual information about them, you will need to research – just don’t confuse opinion with fact.

Quote:

Originally Posted by jim_c

What is your opinion on what makes one battery better than another?

What makes any (consumer) item better than another? Its technical design, quality of materials used, and quality control during assembly/ manufacture. In the 60’s a GM engineer said that the only difference between a $6000 Cadillac and a $1500 Chevy Impala was QC – both quality control during assembly, as well as quality of every part in the car, and the QC of each individual part. The basic cars were the same, design wise.

But perhaps you mean “how do I choose which battery to purchase”? I would personally choose a low-maintenance or maintenance-free battery, just for convenience. However, I have discovered that it is no longer practical to learn the chemistry used in a specific battery, which determines the level of maintenance that will be required (how often to add water). Advertising claims are not sufficient or valid, in my experience.

So I rely on CONSUMER REPORTS, and try to match the features that I want against their performance rating, for a specific battery. Note that their battery brand recommendations differ from year-to-year. That is because the battery brand name has no relation to the battery manufacturer.

At best, you can choose a *sealed* battery, without removable water fill caps. We can hope that such a battery will not actually require the addition of water. There is simply no consumer level information available for any car battery.

A battery brand, such as CostCo or SEARS/ K-Mart, will change manufacturer supplier from time-to-time, based on their supplier cost (not yours), and availability. A battery brand may in fact use more than one manufacturer supplier, depending upon the specific battery model. What you are really buying, is both the reliability rating from CONSUMER REPORTS or other trusted source, plus the warranty provided by the retail seller.

As for the AGM or GEL type batteries, they claim to last 2-3 times the life of a *regular* battery. But they cost 2-3 times as much as a *regular* battery. However, I remain unconvinced that an AGM or GEL type battery will actually last 2-3 times the normal 4-years life of my batteries, which would be 8-12 years life. Besides, as a replacement battery, that would likely be longer than I would keep the vehicle.

An AGM or GEL type battery is by definition maintenance-free, since no water can be added. But under certain high heat conditions, such as living in Phoenix or Las Vegas, adding water may be required, and it cannot be done. Also, I am unconvinced that such batteries are a good fit for an older vehicle with a charging system that was *not* originally designed for such batteries, regardless of what the manufacturers say.

Nonetheless, CONSUMER REPORTS has highly rated a very few AGM batteries, but none for the RDX. And for certain applications, they can be a good choice. I would expect that the price of such batteries will continue to fall, and their reliability will continue to rise.

Quote:

Originally Posted by jim_c

... How different are they [ed: battery] internally? It seems to me (with no insider data at hand) that almost all batteries must be pretty similar if they use the same basic chemistry and the same basic materials

Well, sure, current car batteries are basically the same as they were 100 years ago. But that is like saying an LCD digital HD-TV is basically the same as a black&white TV with tubes and a CRT screen from 50 years ago.

Current batteries, all batteries not just car batteries, are built using not just the latest *chemistry* tech, but the latest knowledge of physics. The battery may be cheap crap, but its crap based on the latest technical knowledge, so that the manufacturing cost can be absolutely the lowest possible, while the battery still has an accurately predictable life.

After all, every battery has some sort of warranty. It may not be much of a warranty, but still, the battery is built to match as closely as possible the specified warranty, so that the company does not have to replace them (the battery) for free.

So, there are batteries with a FREE replacement warranty of 1-year, and some with a FREE replacement warranty of 4-years. Do you really think that those two batteries “must be pretty similar”? Similar yes, but basically the same – well no.

Quote:

Originally Posted by jim_c

... How different are they [ed: battery] internally? ... they use the same basic chemistry and the same basic materials

Well, no. You might as well claim that cast iron is the same as aircraft steel. They both contain iron and carbon – but are not the same. Not even battery cases are always the same, and that is the most simple part of a battery.

A car battery can be built with charge plates using (1)all lead, (2)lead-antimony, (3)lead-antimony/ calcium, (4)lead-calcium/ calcium, (5)etc. And those are just the wet-cell sulfuric acid types. Then there are the AGM (absorbed gas mat) and GEL types. And that is just the chemistry side.

There is also the physics of how those charge-plate materials are combined. And how those basic materials are combined, on a molecular level, will determine battery life, as well as maintenance requirements.

My OEM RDX battery required the addition of significant water every 6 months, indicating a cheaper *standard-chemistry* design. The AC Delco battery in my Chevy required no (zero) water to be added in 5 years of use, indicating a maintenance-free-chemistry type design. Fifty years ago, there was no such thing as a maintenance-free car battery.

My OEM RDX battery lasted 4 years. My last Chevy AC Delco battery lasted 5 years.

Quote:

Originally Posted by jim_c

... It's not a complex item [ed: battery], it doesn't have any moving parts, etc.

A TV or home computer (exclusive of cooling fans) has no moving parts either, but the technology to build a current TV did not exist 50 years ago – as for computers?

Current car batteries, well, the better ones anyway, also could not have been built 50 years ago. Which is precisely why one car battery may cost $50 and another $200. That is, the cheap battery is probably built using 50 year-old chemistry, but using current physics tech and quality control.

Of course, just because a battery costs $200 does not mean it is made using the best materials and latest chemistry/ physics-tech. That is why I buy my car batteries based on the reviews in CONSUMER REPORTS or another source.

Quote:

Originally Posted by jim_c

... And I am very interested in your opinion of Acura's own branded batteries. Many people criticize them and say they are cheap or low quality,

For a true understanding of the problem with current batteries, consider the following. If you allow most modern cars to sit for 2 months, they are very unlikely to start. Why? The constant parasitic electrical loads, drawing current while the car sits parked. Older cars had no such parasitic loads, and could sit for a considerable time, and still start. Older cars also had much lower total accessory electrical loads.

The OEM battery in my 2009 RDX was covered by the 4-year bumper-to-bumper warranty. That means a FREE replacement within 4 years if the battery failed. Can you name one other battery with that length of FREE replacement warranty? I did own an AC Delco battery with a 50 month FREE replacement warranty. But current AC Delco batteries are made in China, now warranted only for 3 years.

As for “many people”, well, this forum has a few hundred members, only a few of which have complained about the battery. And a number of those people have received a free Acura dealer replacement battery. If the Honda OEM battery was really a problem, Honda would be handing out a lot of free batteries, which is not the case.

If there is a problem with the OEM Honda batteries, its because the battery has a low reserve, not the quality. That is, the OEM Honda battery in my RDX was rated 440cca, which is typical, depending upon the particular Honda/ Acura model vehicle.

And the lower the CCA rating, the less the battery weight, all else being equal. And the lower the CCA, the more difficulty starting an engine at zero degrees. And that can lower the life-span of the battery.

But the RDX alternator is only rated at 100amps output. A lower amp output alternator, is a physically smaller (and lighter) alternator. With all of the RDX accessory electrical loads, 100amps is marginal alternator output, but specified because it improves gas mileage, and every tiny incremental increase in mpg must be sought by Honda, in order to meet USA CAFÉ mileage standards.

Using a 640cca battery in an RDX is (almost) pointless, because the alternator cannot keep it fully charged as well as it can the OEM 440cca battery. Unless the vehicle is consistently driven at least 10 miles per trip, any battery is simply going to run-down. The RDX owner manual specifically states that continued use of the seat heater on HI will run down the battery, no matter how the car is driven.

My 1998 Chevy also has a 100amp alternator, but was delivered with a 690cca battery. However, my older Chevy does not have nearly as many electrical accessory loads as my RDX. And the Chevy also has trouble keeping that larger battery fully charged, unless driven consistently.

Do not misunderstand – I did replace the OEM RDX 440cca battery with a 640cca rated CostCo battery. The higher rated battery provides a larger reserve, meaning it can sit longer and still start the car, especially in very cold weather. But because of consistent short trips, I must also use a trickle charger with this battery, once a week, usually over the weekend. Otherwise, the CostCo battery will eventually run-down (discharge).

The other problem with the OEM RDX battery is that it required regular water top-up. It is clear to me, that most of the people on this forum complaining about Acura/ Honda battery life, have never added water to *any* battery. When the battery runs low on water, it shorts and dies.

So, is the Honda OEM battery crap? Well, it certainly is not the most advanced design, nor most maintenance free type available – at least my RDX battery was not. Did you really expect it to be so?

Quote:

Originally Posted by jim_c

... And I am very interested in your opinion of Acura's own branded batteries. Many people criticize them and say they are cheap or low quality, but why would Acura do that?

Simple question – but there is only a multiplex answer. However, I will give it a shot.

Understand that not all Honda batteries are the same. The battery in different models or years of Honda/ Acura may be manufactured by completely different manufacturers, to different specifications. So two different years of the same model Honda, may have batteries made by two different manufacturers, and thus two different CCA ratings, qualities and life-spans, although even Honda would hope both batteries would meet Honda’s warranty period. Any Acura branded replacement battery will also likely differ from the one delivered in your car.

Until recently, there were only a handful of companies making all batteries available in the USA – the cheap batteries and the expensive batteries were made by the same companies. And the same one company makes a full range of batteries, from cheap and crappy to the best available.

Now, of course, China and other countries are making batteries cheaply enough that even after shipping around the world, they can still be sold here in the USA.

The OEM Acura battery in my own 2009 RDX was manufactured by Johnson Controls, as stamped on the battery. Honda makes no batteries. Like every other part in your Acura/ Honda, the battery is *bid* by several companies, then selected based on price and performance match to the specification from Honda. So, if the OEM battery is really not the best available, you may be absolutely certain that is because Honda spec’d the battery that way.

You purchased an Acura, not a Mercedes or Ferrari. Every car is built to a price-point, that is, a price and quality level that the manuf hopes a lot of buyers want to purchase. So, like every other part in your RDX, the battery is built to a price-point and quality level, that Honda hopes the buyer will find acceptable.

For the RDX, Honda specified a battery requirement based not only on price and performance, but also on weight and CCA matched to a marginal amps output alternator, in order to maximize MPG.

Quote:

Originally Posted by jim_c

... I would think they [ed: Acura] would want to put an excellent quality battery in their cars and not save a few pennies per unit using an inferior type.

Honda is both trying to “save a few pennies”, just like every other manufacturer, as well as saving weight, by specifying the minimal acceptable alternator amps output with a battery to match – again, just like every other manufacturer.

My OEM RDX battery lasted 4 years, which is the full Acura warranty period, and I live in an area where the typical life of *any* car battery is 47 months or less, based only on local weather (temperature).

And at the price and performance point of my RDX, I am convinced that Honda made an excellent battery choice. Would I have liked a *better* battery? Sure. Did I bargain with the dealer for the lowest possible RDX vehicle price, below invoice? Sure. Did I compare the RDX price against other vehicles? Of course. Did I choose which vehicle to purchase, based on battery quality? Say what?

Based only on average yearly temperature, the *estimated life expectancy* of the *same* average battery can vary from a maximum of 61 months to only 30 months. Are the people on this forum, who are complaining about battery life, living in one of the more severe (weather wise) areas of the country? That type of info is seldom forthcoming.

Understand that SEARS/ K-Mart in particular, sells a specific battery for both cold and hot average weather conditions, at the same price-point. The batteries are labeled NORTH and SOUTH, and are actually of different basic designs. SEARS also sell specific battery designs for *rough* use, specifically intended for SUV or truck use, where shock and vibration are of concern.

So, is there a “better” battery than the OEM Honda one? Of course. But you need to define better: price, life, average weather conditions where you live, maintenance requirements, off-road use, reserve power (CCA), what? There is simply no one battery that covers all conditions.

=====================
Well, I don’t know if anyone will actually read the above, but perhaps it will answer at least some of the questions asked. For more information, there is a lot of info online, although much of it is bogus, just like every other online subject.

But certainly, in one sense, batteries have not changed *much* in 100 years – else we would all be driving electric cars powered by (cheap) batteries that last 20 years
---eof

NBP04TL4ME

Good stuff!

pjhalifax

Wow, thanks for taking the time to post this. I find it really interesting -- especially the part about Acura's decision-making regarding the alternator size. I just got my 2008 RDX and noticed in passing that the battery was smaller than what's in my other car (Saab). Now I understand some of the reasons why, and also what to look out for as the RDX battery, which is almost new, ages.

HBob

Thanks for the post.
Comes in handy on a brutally cold day where the car won't start.

Here I was thinking that car batteries would last 6-7 years so my 2010 RDX shouldn't need a new one yet. And the wife has drained this battery a couple times in the past too.

Time to go to Costco to pick up a new one.

NBP04TL4ME

Mods should consider making this a sticky.

Joel H

When the post is mentioning "CostCo" are they meaning "Costco" or is this a different business?

Joel H

Opps, I see that it probably is Costco . . . I'm too new to delete so will when I get a chance

Great write up.

NBP04TL4ME

Too new?? You joined 2 and a half years ago............... but you only have two posts!?!?!?

01acls

I recommend you get the highest amperage rated combination deep cycle and starting gel battery you can fine if your life depended on it.

The Opima Yellow Top would be a good choice.

1. Good cca.

2. Good reserves.

3. Deep cycle to withstand deep discharges and recover without pernament damage or lessen the damage. Will handle deep discharges much better than standard wet batteries.

4. Gel Optima for zero maintenance... Leak proof... ie. Upside down mounting.

5. Gel Optima for extreme use... vibrations. Patented Spiral gel cell technology.

6. Optima claims it should last twice as long as a standard wet cell battery.

NBP04TL4ME

Curious as to why you would make this recommendation. Did you have a life depended on it situation? Gel or AGM are good batteries, but overkill for most people / applications.

01acls

I read this in this post.






And so is driving a V6 vs 4 banger. WTH???

NBP04TL4ME

LOL - then we should all probably be driving a Sherman tank or some sort of other all terrain, all purpose, all weather conveyance.........

01acls

LOL ok then i'll like to drive an ambulance plz... lol

RDX8002

I picked one up at costco for $72 after returning the core. Took me about 10 mins to change, finding the audio code was a drag. So far (a month in northeast fall weather) the battery has been a good.

NBP04TL4ME

^^^^ Not sure where in the Northeast you are but the weather here in eastern MA hasn't even been anything close to a test for a new battery.