Power stations are good option as also get extra battery storage. Can be charging while riding then use it topup bike battery at lunch and at end of day.Note: Adapter required for what looks like an XLR plug to connect to Bosch (batteries manufactured between between Classic and Smart System, i.e., the majority of batteries out there in circulation).
The Bosch travel charger (no longer in production) is a 12V CLA charger with the Bosch plug. Also 36V/2A output, allows you to use a panel with a power station like the Jackery.