BB Curve :: Battery Icon With Red Line?

Yesterday my blackberry was on with nearly dead battery, so I plugged in the charger and it shut down and rebooted to a screen with a red line through a battery icon. I assume this means the battery is completely dead but I have tried the battery in another phone and it was fully charged. I have also tried other batteries in my phone which just resulted in the same thing. I also had this problem before and somehow it solved itself within a few hours, but it seems like this time it isn't.