The battery of the RX chip (modular battery) charges when the bike and, depending on the year of manufacture, the lights are switched on. To recharge the chip battery, you can simply ride your bike with the lights switched on. As a rule, the chip is fully recharged within an hour.
The battery consumption depends on various factors, including the parking location and the availability of mains power. You can see the battery status in the RX Connect app in the bike status. You can find the bike status under the Wi-Fi symbol on the map screen.
You can call up the current charge status of the battery in the bike status in the RX Connect app. You can find this by clicking on the Wifi symbol on the map screen.