Our robots make use of rechargeable Lithium Polymer (LiPo) batteries. A good rule of thumb is to use 1,000 mAH (milliamp hours) per motor. For a Quadcopter, a 4,000 mAH LiPo should work nicely. Although the copter can only use one battery at a time, we recommend having at least two batteries in stock; more batteries means more flight time. You’ll also need a charging station for your batteries.
LiPo batteries must be handled carefully. Do not discharge batteries lower than 3 Volts per cell. A LiPo battery cell is considered charged when its voltage reaches 4.2V, do not exceed this voltage.
Erle Robotics is not responsible for the bad use of LiPo batteries
If you wish more info about LiPo batteries, check this link