Low capacity for 9 volt NiMh

Prolly a combination of the fact that NiMH tend to have less capacity than alkalines in the first place, and difficulty in making good, teeny NiMH cells.

These are just guesses.

The way battery makers specify "mAh capacity" favours non-rechargeables like alkalines. In actual use, a NiMH type may outlast an alkaline.

All depends on the actual discharge current and the lowest voltage your device tolerates. NiMH cells tolerate higher discharge rates better and have a steady output voltage compared to alkalines.

.... Phil

I bought a couple of ESB lithium ion 9V batteries rated at 600mAh. Only had them a few days, so jury is still out. I expected them to be 8.4V, but the two I got stop charging at 8.04 and 8.2V respectively. That's a LOT of lost capacity relative to a 8.4V terminal voltage. Only have one indication of low voltage cutoff, but seems to be 6.5V-ish

My voltmeter throws a low battery indication at 7.2V. I'm hoping that the LSD ability is more benefit than the loss of voltage.

Some interesting info here (doesn't cover 9 volt batteries, though):

I've no idea how accurate the info is.

Interesting about your 600 mah batteries.

My EBL 300 mah 9 volts charges to 9.53 volts.

Andy

If it's the rechargeable lithium, I'd be worried about that. If it's the 9.6V NiMH version, that sounds about right.

Thanks.

Andy