I have a 6yo laptop whose battery died within the first six months. I have been using on ac power since then. I read an article about repairing the battery by disassembling it and replacing the individual batteries which make up the laptop battery. I managed to pry the top off the battery and there are 8 3.7 volt cells inside (see picture). I check on the cost to replace the cells and it is reasonable seeing that I can no longer find a battery for the Toshiba. I also found a very sophisticated circuit boare in the battery (see picture). My question is, how do I know whether or not the circuit board is functional and what the heck is it supposed to do??
there are pictures at misterfixit.com/Toshiba
there are pictures at misterfixit.com/Toshiba