Knackered batteries?

[Gruntfuggly]

I've got a few 7.2v battery packs that don't seem to be charging. I've tried trickle charging them for at least 24 hours. I bought them last year and have only used them perhaps 10 times. Is there anything I can do to make them work again? Is there a way to test if they *really* are knackered?

[Twmaster]

Sounds like they are shot. Overcharging and over discharging is very bad for cells so it is possible that you've killed them. Also, el-cheapo no name cells will not be as tolerant as quality cells from companies like Sanyo and Panasonic.

Nicads are especially susceptible to this.

[WillyChang]

If they're shorted (but not "open circuit") try Jerk them to life with a fast charge.

[rroodd]

Yes, it's possible they may need a couple of charges-then-discharges, if you know what I mean, to bring them back to life. Some NiCd's will respond well to this if they've been sitting a while,...but like Twmaster said,....you only get what you pay for,and the cheaper cells won't cop too much abuse.

Rod.

[Jameshs]

you could try freezing them, i know it sounds stupid but leave them in a sealed bag and put them in the freezer for about two days then take them out one by one to trickle charge them. the thermal shock sould clear the cells but only do it to nicads. i did this to all of my batteries after not using them for about 7 years and some even 9.

After that just keep using them and they should get better and better.

Try it what have you got to loose

[wriggleandgiggle]

quote:Try it what have you got to loose

id="quote">id="quote">

Your home if your mum or girlfriend find out!

"I'll just get the chicken out of the freezer for tomorrow's lunch"

[Gruntfuggly]

Thanks for the suggestions - in fact one of them seems to be getting better already after just trickle charging it again...