The module's schematics are pretty simple:

As we can see, the microcontroller will read over i2c both data from the IMU and the battery's State-Of-Charge (remaining percentage) as well as the joystick's position if it's present.

All of this data will then be posted over Bluetooth 4.2 for the client to process.

The battery is of course charged directly onboard, so plugging a microUSB cable is all that's needed.