It may be the battery level measurement software that needs calibrating. Let it rudowning until it actually turns off on its own. Then charge it back up to full. This will recalibrate it and you should be ok. If not, new battery time.
put it on a hobby charger and do a discharge test on it and see what capacity it shows. It is possible to have a battery with internal problems that still shows the nominal voltage but is incapable of delivering basically any current at all.
I had one that reported 3.8V but when discharging only gave a total capacity of 340mAh. With that kind of total capacity, it would run a phone for about 30 seconds and die still reading 3.8V
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The battery is Japanese. Blackberry batteries have a security pin number that must be accepted by the phone to work. That means no cheap batteries for me.
I wish there was a light that ran off of these. It would be a good emergency light that you could charge with your cellphone in a car with the cellphone charger.
I have drained this battery to shutoff several times. No go. It actually seems to be getting worse. The battery shows flat right now with 3.6 volts on the cell. I have screen shots that I can post later.
I don’t have a hobby charger but if the phone is guessing the battery life by the current output, then that would make more sense why the meter shows zero but the voltage is still quite high. I guess I am just going to have to buy a battery tomorrow. It’s cheaper than a hobby charger, haha
Looks like I really am buying a battery tomorrow. This one is acting REALLY strange now. Charges for a minute then says “operating on external power” for a minute then repeats the process. This thing better not explode on me while I am asleep.
Well, wasted 40 bucks on a new Blackberry brand battery that does the exact same thing. At ~30%, the battery will suddenly drop to 8% capacity left and the phone warns me of a dead battery. Completely not amused. I might just buy out of my contract and go get an iPhone 4S from Verizon next week...