I have 3 Tenergy chargers as well as their Premium Pro (NiMH) batteries for AA and AAA. The AA are 2800mAh batts and the AAA are 1100mAh batts with a 2100 recharge cycle lifespan and the ability to hold 85% charge for a year - more capacity than any other battery I’ve found… and I can vouch for the charge hold… still using some Tenergy Premiums (older line) from about 5 years ago, so I’m pretty well sold on their longer lifespan claims as well.
The only problem I’ve found so far with their higher capacity “Pro” batteries is they are a touch larger than a standard alkaline in circumference so they wouldn’t fit in one of my cheapy flashlights, but that’s the only device so far that I’ve had a problem with. Otherwise I’m very happy with the performance and now own probably close to 50 batteries from them, including a couple of their Premium 9v and a number of their Li-Ion CR123A batteries. I’ve been using them for a little over 5 years now and have yet to throw one of them away because it went bad.
I do buy them direct here: