Well, its not so much a hack, but rather a short term work around. my keyfob battery had died and when I popped it open, it had a CR2025. I happen to have another and I popped it in and it worked. short time later the keyfob would work intermittently as it is slightly thinner in size. I decided to investigate further and found the proper size to be CR2032. I read up that CR 2032, 2025, 2016 all provide the same 3V with varying thickness and longevity. I still dont have CR2032 at hand so I decided to put 2 CR2016 + to + together and both - facing opposite directions. it fits the slot perfectly without the outer battery working at all. it just holds the space in and keeps the first battery in tension to both + and - connections. CR2016 only lasts half of CR2032 but at least it works now until my CR2032 comes in.

 

I have had a 2025 in my 2005 TL OEM FOB forever. And you are right both the 2025 and the 2032 are the same diameter but the 2032 is thicker. Fortunately, the battery is mounted with the topside (+) down and the top side is what is used to secure the battery to the plastic case, which is upside down. The added "thickness" is actually on the Negative (-) side.. So basically both batteries fit securely to the plastic case (shell). And there are a few tiny hooks on the casing that holds the battery. But I did notice some of the slack was taken up when I closed the casing back up. But it closed fine. So, maybe I had the smaller battery in there by mistake? I have no idea which battery is recommended. Either way, I think both will work fine and last a long time either way! The 2032 may be slightly heavier! So it may make your FOB feel slightly heavier. The only reason that may matter to me is because I run with the FOB in my pocket. No keys, no wallet, just the FOB. Because I drive to where I run, but I dont carry stuff on me when running, except a FOB. So sometimes a heavier FOB kinda bothers me when I run, but it is still light weight and not much notable difference and you definitely would not notice a difference with keys attached, while walking around shopping or whatever.

by the way, I am calling the "topside" of the battery as the side that wraps around to the other side. The top side (+) is a bit wider than the bottom side (-)

 

This is some good info to know. In the rare instance I need a replacement and don't have the correct battery lying around. Might test the theory out in other remotes as well.

 

btw, I think the 2016 battery is too thin for my 2005 TL FOB. It may wiggle too much.