Is there a maximum charging current this battery can handle?
When using our charger with a USB port, all ports have 5 volt output but the amps are different. Port technology keeps improving. The latest is a 3.1 port. 1.0 & 2.0 Ports - put out 0.5 mA 3.0 & 3.1 Ports - put out 0.9 mA We do not recommend using a wall charger that can accommodate a usb charging cord. The wall units have outputs dependent upon it is intended original use or pairing. In other words if you use a wall plug system intended for use with a tablet or phone it could exceed the input of our battery. We hope this information is helpful.