How to Charge 11.1V Lipo Batteries with LiPo Charger
Lithium polymer (LiPo) batteries were originally developed to power devices such as cell phones, but their light weight, durability and output voltage has made them a favorite of remote control (RC) enthusiasts. Each LiPo battery cell has an output of 3.7-volts, while most RC models operate on about 10 to 12-volts. So, LiPo batteries are made into battery packs and wired in series. Wiring in series combines the output voltage of each battery--three 3.7-volt LiPo batteries produce 11.1-volts. Charging an 11.1-volt LiPo battery pack is simple, but it's imperative that you only ever use a LiPo charger.
Check your LiPo battery pack to confirm the combined voltage is 11.1-volts. Check your LiPo battery charger to ensure it is able to charge at 11.1-volts. LiPo chargers have variable voltage settings, so make sure to set the charger to 11.1-volts. Setting the voltage higher than your battery pack's output could be dangerous; setting it too low may damage the batteries.
Set your LiPo charger to charge at 5 amps or less. Charging at less than 5 amps takes longer, but if you exceed 5 amps you can damage your battery.
Check your LiPo battery charger to ensure you don't overcharge the battery. Some chargers will automatically turn off once the batteries reach their optimum voltage; others will continue to charge, and this is potentially dangerous. If your charger doesn't have an auto cut-off, regularly check the voltage indicator. Once the charger indicates 11.1-volts, turn it off. Do not exceed 12-volts.