我前几天刚升完级也这样，试了下面网页推荐的方法，现在已经完全解决，一下午不用电话只掉3%。

11 Tips to Keep iOS 7 From Destroying Your Battery Life

http://gizmodo.com/how-to-take-care-of-your-smartphone-battery-the-right-w-513217256/1416982678