I had a Third Reality contact sensor doing this. Was already on current firmware. Changing to the regular contact sensor driver (with temp) and then just marking the temp as disabled solved it for me.
Here is some info as to why that fixes it (and check post above also): Battery reporting 200% (Linkind devices) - #73 by mike.maxwell
This may be of interest also (same thread): Battery reporting 200% (Linkind devices) - #67 by jtp10181
