Two of my series 1 traxxas batteries are already stupid! I have 4 of them and got them all on Christmas. Two of only run at almost full power when they are warmed up. If I put them in front of the heater then use them they are almost normal. If I don't they take about half of the battery life to warm up and start working. Anyone know why? I have been using the traxxas ez peak charger on 1 amp. I let the batteries cool before using/charging them. I never let sit of 2 hours without charging them. I only run until the car starts slowing down. Anyone know why they could be doing this?