IPAD 2 battery % doesn't refresh after fully charged

My IPAD doesn't accurately reflect the correct amount of battery %. If it says the battery is at 28% then after fully charging it..it still displays 28%. It won't refresh the % until I complete turn off the IPAD then turn it back on. I've fully restored and reloaded the IPAD but the problem still exists (and am using the default settings). This problem happened after the update prior to installing version 9.0.2 (13A452). Then after I installed 9.0.2 (13A452) my IPAD intermittently restarts and the battery issue still exists.

How do I fix this problem?