14.Charging and battery life of the M21

Fast charging protocols including PD2.0 or above are supported. If the power adapter does not support neither the above protocol, it will not trigger the fast charging function and super high gain but just common charging. For non-fast charging adapters, it is suggested to use the 5V 1A/2A power adapters.

The POWER IN port only supports PD2.0/3.0 fast charging, while other types are recognized as normal charging. When connected to PD3.0 fast charging via the POWER IN port, the maximum charging current can reach approximately 3.5A.

The USB 3.0 port doesn't support fast charging.

Battery capacity: 4000mAh

Battery life:

15 hours (3.5mm standard headphone out)

11.5 hours(4.4mm standard headphone out)