The "old" AA Eneloops were rated to hold ~ 80% of charge after one year, with a 2 Ah initial capacity. I don't remember the AAA specs.

There are two new AA Eneloops. The white ones still have a 2 AH capacity but are rated for 1500 recharge cycles and a 3 year at 80% rating. That's lifeboat or stored kit territory in my opinion.

The new dark AA Eneloops (Eneloop X?) have the same rating as the old Eneloop but a 2.5 Ah capacity.

It's worth noting that in my testing Eneloops almost always come very close to rated capacity (within 5%) or even exceed it. That's almost unique among NiMH batteries.


This feature is referred to as LSD (no, I didn't make that up!) or Low Self-Discharge.

LSD batteries require better materials, manufacturing purity, and electrodes. I suspect the can also has to be better to resist chemical attacks from the contents - you can't claim N years of shelf life if the can fails sooner than that.

Lithium calls have better cans too, mainly for liability/safety reasons.

I have read elsewhere that charged cells don't attack the can as quickly as discharged cells and that LSD cells are shipped charged to protect the can, although it may just be because they can do it (non-LSD NiMH would discharge before final purchase anyway so there was no point in the factory worrying about it pre-LSD)


Tenergy sells LSD true D, C and 9v cells, as well as AA and AAA. Their LSD D cell is rated at 10 Ah.