Apple bluetooth keyboard always shows 100% charge

03/14/2018-Old question, still an issue. There are several old posts/replies from a few years ago and there was never a solid solution offered that I could find. I have tried all solutions that were offered to no avail. I have two Apple bluetooth keyboards, both identical but one is several years newer than the other. I have the issue with both keyboards, which tells me the obvious, that it's not a keyboard issue. I'm running a late 2013 27" iMac with High Sierra 10.13.3, which is the latest OS available as of right now. I am using an Apple Magic Mouse original version and also have an Apple Trackpad connected that I use occasionally. Also Beats BT head phones. No issues with any of the other peripherals, Apple or Beats. For the record, I'm using Duracell Alkaline batteries but have used other types/brands in the past as well as rechargeable, all with the same result. Any new help and/or info is appreciated.