slow charging solution
Months ago my Note 2 got real slow charging or if I used the phone on AC it would not recharge or the battery charge level would decline slowly.
The solution was to use a short USB cable, 18"instead of 4-5 feet. Going to that improved charge rate dramatically. It appears to me that the shorter the USB cable the faster most any smart phone will recharge.
An app that helped me find this solution is one callled "battery monitor widget" which will estimate the charge rate in mA and will indicate if the battery is discharging while on AC, a problem I was having.
In the mean time switch to a short USB cable and you'll probably find recharging is faster.