... is lithium battery,Capacity is 1900mAh.feature:1.Power Switch:ON/OFF.built-in lithium battery.2.It also ... it out .5.How to Put Your Iphone4 on Charge:First of all,pls turn on the switch,When lithium battery is ... of power,pls insert iphone4,then turn on the switch on back side,in that case it is charging. ... battery is dead,pls insert USB cable into it,connect other port with computer USB port.Now it is ...