Battery Full [Q] Tablet won't take a full charge

Hey Everyone,

So a while back my tablet would stop taking a full charge. It gets up to around 70% and then it just sits there forever. I haven't tried connecting the tablet straight to the charger yet as I just keep it plugged into its dock all the time. I'm currently running the latest nightly from CM. I've tried whiping my battery stats and other things to no luck. Any thoughts? Thank you all in advance for your help. I've also googled this but can't seem to find anything like what I'm experiencing.