I normally charge my iphone and ipad mini while I am on the run. The reason being is because the traffic at my country which makes me use waze a lot on my iphone while ipad mini was connected to audio and get charge automatically from my head unit (the head unit got usb connection). Everybody been telling me that charging the iphone and ipad mini on the car is not good cause it will damage both devices sooner or later as the electricity is not stable. The ipad mini got electricity from head unit so I don't know if I should worry about it, since I need it to play music from mini's itunes anyway. For the iphone, indeed sometimes it gets pretty hot. So I just been thinking if I buy one of those power bank, connect the car electrity to power bank then power bank to iphone, will I transfer the risk of electricity volatility to the power bank instead of the iphone?