Perkins 4403050 Lipo Battery Protector (2-4 Cells)
Connect this to your lithium polymer battery and protect your battery from over discharge and increase the life for your battery. This clever device will reduce the power to your motor if the battery voltage drops to 3 volts per cell and will cut the power to the motor if the voltage drops to 2.6v or below! It even has a bank of LED lights to give a visual display of the battery's condition. it will also protect your battery from overheating by reducing the power to the motor, how clever is that!