Battery rejuvenation.

[Grandad]

I tried to post this topic in the technical section but was informed that I did not have permission. Am I not old enough? Perhaps it could be moved.


On the 29 September 2005 I bought a Giant Twist Lite Gents electric bike. The original, 6.5Ah, battery is still going strong. In March 2007 I bought two 24V 8Ah Salisbury NIMh batteries to provide extra powered milage.

The first (Salisbury1) has performed well until the present time (July 08). The second (Salisbury2) has never been as good as the other one but still provided reasonable extra mileage. However in late June it failed after about three miles. As it is out of guarantee, I decided to have a go at rejuvenating it by subjecting it to charge/discharge cycles and to do so I set up a test rig.

Here are graphs of my results, more information here.

Anyone else tried anything similar? Any comments?

Right, off to watch the Tour de France on the box.

 

[flecc]

NiMh can often be rejuvenated as you've shown, but thanks for the very detailed results and reporting. It made
a very interesting read.

As for the battery differences, with the changeover to lithium there's been increasing difficulty in sourcing high discharge rate D cells at viable prices for manufacturing batteries.

The later ones supplied have usually had less good discharge rates, leading to a drop in performance in
all respects, and more than one manufacturer has suffered from this.

So more of them go lithium, but that's no help to owners of existing bikes without the lithium option.
.