How do I charge the NOHRD Bike battery?

In order for the NOHRD Bike to communicate with the app via Bluetooth, the circuit board must be supplied with power. For this purpose, the NOHRD Bike comes with a suitable power bank. The power bank must be pre-charged before first use; charging via a wall socket is recommended. The power bank is then pushed into the battery compartment under the gear box and connected to the bike via a cable.