Rob Graham wrote:

One thing that hasn't been said is that NiCd cells retain their life
best if they are discharged almost fully before recharging. They
collect what is known as the memory effect if charged when half
discharged and tend never to have their full capacity thereafter.
NiMH cell do not hav this characteristic and can be recharged at any
time.

rob



Urban myth Rob.


It happend once with a very regular charge/discharge regme on some
spacecraft. No one has ever really demonstrated it with random charging.

Nicads lose charge anyway over about a year. Or faster. NiMh are dead
within a few months if not charged. They recover tho.