try to check on many rechargeable batteries, before that i knew only eneloop,
try on what on the market now
1. eneloop: eneloop is the first comer and many knew this one.
eneloop has 2 size aa and aaa
and has many adaptor like c and d
it’s kind of specific NiMH (nicle Metal Hydride) that can check how many battery charge left and preserve the battery life.
it’s kind of mobile booster
so you can sure for this ( and so i am)
note: eneloop is product of sanyo
2. ReCyko: recyko is another battery brand;
same as eneloop come with its own charger and mobile booster
the different, i cannot see it’s C and D size adapter
note; recyko is GP (gold peak) product
there are still many brand you can check in wikipedia