Does anyone know how long it takes to charge (via USB port) a dead battery to full? Someone yesterday said 20 minutes but I have a hard time believing that.
20 minutes, and the battery explodes. 3 hours is about right when doing the math.
PS - Just did the math, and at the battery's maximum charge rate of 4A (really pushing your luck), it would take 36 minutes, unless the battery explodes and you have to start from scratch