Re: Issue with notebook (maybe the battery?)
On 28/03/17 16:24, David Wright wrote:
> Charger in:
> Charger out:
> IOW my baseline after 8 years is about 20% capacity.
I think at that state it is 95% (828/872) and I think these correspong to 8.28v and 8.72v which is as good as new.
At 8.72v the charging current is switched off to protect the battery. I would think these are 2 x 4.2v polymer batteries with an x amount of amph. What distinguishes a good battery from an old and tired one is the voltage drop after a certain load has been placed (resistance) and how long does it take to fall below a functional level.
In most cases these batteries will go down to 3.2v under load and this is when your electronic circuit will cut them off because amps go so high it may fry itself. A tired battery will show 4.18 and 2" after you hit the power button it will go down to 3.1v.
A broken battery will not reach 4.2v or it will go up in smoke while you are trying to charge it. The problem with those twin packed cells in series is that due to manufacturing inconsistencies you can hardly find an identical pair ever. One is a little bit difficient to the next. Which means that at 8.6v one is almost 4.4 the other is 4.2 and one is getting overcharged the other stays undercharged. At the end of their season the one is as good as new the other is all warn out from overheating cycles. When you open a cheap tablet up that has had battery problems it is almost visible which one of the cells is problematic. The other is always good!
Nothing like a fresh marine deep cycle acid lead battery, now that is some good vaping current :)