I have an E-Maxx w/ a 8XL and 9920 geared 22/66. Runs great on 16 cells without getting hot (Throttle EPA set at 80-85%). The problem is my runtime. My GP 3700's loose considerable power after 7-8 mins at the track and I need a 10 min run for the A-Main race. The batts are 9 months old and were run and cycled regularly. Could my batts have bad or gone flat?