When the iPhone is fully charged, the battery case will time out and stop charging. If the 30-second time-out happens only when your iPhone is fully charged, then it is normal and you don’t need to worry about it. However, if it also happens when your iPhone is not full, then your battery case might be defective. In this case, please provide us with your order information and we will assist you with a potential refund, replacement, or warranty service.