does all recharable AA batterries in the market are all niMH?

Question

if no, what brands. thank you.

Answer 1

The predominant market for rechargeable AA batteries is NiMH. It's probably hard to find NiCd's since most consumers are scared off by their propensity to exhibit memory effects due to partial discharge/recharge. And rechargeable Li AAs are still a bit on the expensive side and can only be found at some of the more exotic battery sites.

Answer 2

No.

Sanyo eneloop. http://www.eneloop.info/

I used it for my flash gun. It is anytime better than 2500mAH AA NiMH.

The problem for NiMH is that the batteries will fully self- discharged in less than 30 days.