This A123 Systems ANR26650M1-B rechargeable battery (or accumulator) has a LifePO4 chemistry. They have the advantage over conventional Li-Ion batteries of being more durable (higher number of charging cycles), less sensitive to partial charges and withstanding higher currents. They are also more reliable and the voltage delivered during discharge is more stable. These batteries are also less polluting and can be stored for a longer period of time.

This model provides a voltage of 3.3V for a capacity of 2500mAH. It can be used on some power supply modules (sold separately) using batteries, the latter having the advantage of providing a cleaner and more stable electrical signal to audio devices and modules. Ideal for high quality audio playback.