Hey. I've noticed a similar pattern via battery monitor widget, tho nowhere even close to ws prononced as yrs. I generally monitor the mA rate and it goes from -2ma steadily until 80%, the rate then speeds up. W moderate usage, i get roughly 2 days out of the sgp before charging, when there's roughly 30% or less left.
I also remembr some folks mentioning that the battery wont report greater than 80%; i imagine that 80% acts a sort of border where he readings r concerned.
Try out that program i mentioned to monitor usage. Personally, im on entropys kernel and chips rom (occasionally switching to paranoid android), have undervolted it slightly, and added a few init.d scriptsl aiming for optimal battry life. Also, try out watdhdog lite to monitor any apps that might be wakelocking improperly and Gemini app manager to disable ann0ying apps from starting on boot.
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