The battery is soldered on the PCB and the two are stuck together using 1mm thick foam double-sided tape (DST). The DST may also help with reducing water damage on the PCB by protecting the sensors and ICs.

There were no fasteners holding the PCB and the battery to the body.

The device uses an EEMB 3.7V 220mAh Lithium Polymer Rechargeable battery. This does not seem to be available anymore on their website.