Lithium Ion battery charge display question

[Albrieo]

Hello guys. Not sure if this is the right place to ask.

I have a Playstation Portable I acquired some years ago, and my original battery died a while back. Since genuine batteries for this device aren't sold anymore I purchased some generic ones and tried it out.

I bought three, one of them never worked, the other died after about a month. The third one is still working, except for one thing - the charge display. The battery points 100% after recharging, but I can keep charging it for a long time before the PSP led points the charge is over; and during the use, the display does some insane things like dropping to 10%, then go back up to 70%, then die out of blue pointing 1% left.

My question is what causes that kind of thing? I don't know how the device reads how long the battery will last before needing a charge, but I see no point on this weird behavior if the battery works properly. Could someone tell me how the reading works?

Thanks in advance.

 

[(*steve*)]

It is impossible to answer your question.

Clearly the functionality is not perfect, but it is not possible to say whether this is poor design, a software bug, user error, the result of a fault, or anything else.

In general the "fullness" of a battery pack can be measured 2 ways:

1) a simple measurement of cell voltage
2) measurement of power in and power out and then displaying something a little more complex than the difference between them

Most likely your unit uses a version of (1), but it's not possible to say with any accuracy.