Depends on the battery chemistry. NiCd and NiMh batteries which were very popular 10+ years ago do have a memory effect: https://en.wikipedia.org/wiki/Memory_e

Depends on the battery chemistry. NiCd and NiMh batteries which were very popular 10+ years ago do have a memory effect: https://en.wikipedia.org/wiki/Memory_effect https://en.wikipedia.org/wiki/Memory_effect LiPo batteries do not have a memory effect, and you should avoid deep discharges.