"Fully Charging" a Li-Ion Battery

[oldbob]

I have a "spare" battery for my T-21 that I picked up at local computer show. I installed it the other day and found it to be at about 2% charge. I know you're not suppose to run Li-Ion batteries down to where they need a "deep charge".

I plugged in the notebook and after about 12 hours it was up to 47% BUT it had stopped charging !! I ran battery down to about 30% and plugged it in again, but once more it stopped about 45%.

Is there are way to "keep charging" the battery OR is this battery on the path of a slow death ??

[redsb3]

There is no way to make the battery keep charging. It has a microprocessor inside that completely controls charging. I'd say the battery you picked up at the show was already half wore out. If it was supposed to be new, then I'd say it was old stock that sat on a shelf and slowly discharged itself, which is not good. If it was used, then I hope you got it cheap because it is half worn out. I wouldn't expect it to last to long in either case.

[oldbob]

redsb3,

Thanks for response, yes, you're correct it probably was "old stock" as I only paid $20 and the guy was probably glad to sell it.

Although it only shows a 47-52 % charge, I have used it for about 1 ½ hours so I guess the price was "about right".