Charge unprotected lipoly with desktop power supply? Answered
I have a few, almost dead 700ma li-polies taken from a macbook battery that would not charge. I have no formal Li-Poly charger, and most commercial charger will refuse to charge these batteries anyway- because most of them are lower than 2.7v right now. I wanted to see if I could revive these, which I have read can be done, using constant voltage and current.
My problem is how to charge these using a common desktop power supply. My setup right now is a charger set on 3.7v, multimeter in parallel (to measure the cell voltage), and a current of 20ma. So far, nothing dramatic has happened thus far. Thing is, the "shorted" light on my power supply is on, and the voltage says its around 2.8v right now (rising slowly). Is this just due to the battery charging? I mean, is this behavior normal for an unprotected cell charging on a power supply?
Also, please note that I do know what lipolys can do. I am not just gonna hook this thing up to 20v and leave to go to town. I am monitoring it, and have it in a large, thick plastic box that is 2ft from a door. I will not leave it on unsupervised.