[jkoral]

Originally Posted by BobsM3Coupe

Do you occasionally use a smart battery charger?

Never on my 135i that was totaled that was going on 10+ years.

But I did start using one when I stopped driving my M2 during covid.

[schmitzna]

Replaced the battery on my 2015 F80 (July-2014 build date) this month (April-2026). ISTA said the battery was getting charged to 40% and rarely to 48%. I noticed that it would not take long in the garage with the ignition on to get a low battery warning.

Bosch 70Ah AGM battery + Hella ground cable with IBS sensor from RockAuto fixed it for $468. ISTA says this battery charges to 80% which is what it is supposed to say. Had to make a new battery hold down clamp because this battery is one size shorter than the original Lithium despite having the same 70Ah capacity.

[eugenebmw]

Originally Posted by jefe2000

Yeah, I replaced mine at 8 years out of an abundance of caution. I expect it would’ve gone to year 9 (and maybe beyond) with no problem.



Indeed! We’re lucky to make it to 4 years on the battery in our ‘16 Subaru Forester XT. They go quick in that vehicle.

The heat from the engine are killing the battery.