How to Match LiPo Batteries to a Motor Size?
There are several types of rechargeable batteries, but lithium polymer batteries (abbreviated to LiPo) are the battery of choice for RC enthusiasts due to the battery's output voltage, light weight and endurance. Matching a LiPo battery to your motor is important: You need to compare the output volts, otherwise you may damage your motor. LiPo batteries produce 3.7 volts compared to 1.2 volts for NiCad and NiMH batteries. Endurance, measured in milliamp hours (mAh), for a LiPo is 2,100 and is higher than other rechargeable batteries.
Place your motor and your LiPo battery next to each so you can match the battery to motor size. Look at the side of the LiPo battery to get its output. LiPo batteries, when fully charged, have an output of 3.7 volts.
Look at the voltage requirement of your motor. It will be labeled on the side. Make a note of the voltage. RC airplane motors usually require 11.1 volts while RC cars can operate on about 8 volts.
Compare the voltage from the battery to the voltage of your motor. If your motor needs 11.1 volts (or similar) to operate, you need to match three LiPo batteries to power it correctly. The simple rule is to divide the input voltage of your motor by the output voltage of your battery. This determines the number of LiPo batteries you need to power your motor.