[ek750]

This doesn’t sound entirely right to me. lead acid batteries do get damaged by deep discharges

even “deep cycle” lead acid batteries aren’t supposed to go to full discharge. from https://www.solar-electric.com/learning-center/deep-cycle-ba...

> Deep cycle batteries are designed to be discharged down as much as 80% time after time and have much thicker plates. The major difference between a true deep cycle battery and others is that the plates are SOLID Lead plates - not sponge. This gives less surface area, thus less "instant" power like starting batteries need. Although these can be cycled down to 20% charge, the best lifespan vs cost method is to keep the average cycle at about 50% discharge.

[xnyan]

It's not. Even a single complete discharge event is often if not usually enough to kill the performance of a lead-acid battery not intended for deep cycle.

[m463]

I'd say dozens of times in my adult life I've dealt with and recovered lead acid batteries that were completely discharged due to the headlights left on or similar.