2010 Acura TL (I believe this to be the original battery in the car)

So I'm on a trip, been in the car for 2 hours (running perfectly fine) and pull over to get gas. Shut off the car get gas, then go to start the car and won't start. Turns over maybe 1 time then nothing (acts like battery is dead). I replaced the battery with a working battery (from a good Samaritan at the gas station), swap back to my battery with the car running and get to my destination another 1.5 hours down the road. The car started immediately with the replaced battery... must be either the battery or connection (which was originally tight and generally clean). The next morning I tried to start the car and.... business as usual, car started right up.

How can the battery die in minutes after having been run for a few hours, then magically recover on the ride home? Is there some sort of strange known issue like this?

 

sounds like battery terminals momentarily disconnected.

 

^ I agree it sounds like the terminals.

However, OP you should have it load tested.. Because if you think it's the original battery, that would make it 6 almost 7 years old which is hard to believe for an Acura battery. For the most part they are known to last 3 to 3 1/2 years tops.

My first MDX the battery died at a little over 3 years without warning while my wife was getting gas. On the TL the battery died at little under 4 years, once again without warning. My son drove it all day with no issue, it was cranking fine and when he went to start it later that night it was dead. At least this time it was in my driveway.

 

I am glad for you but somewhat surprised that you did not fry something in your electrical system while running your car with no battery (during swapback).

 

if he wasn't revving the engine nor doing anything to increase load , the alternator should be providing somewhat constant 12V.