To ensure full capacity of your batteries even after a long period of time, you should let the battery empty completely during operation and then recharge it completely. If you do not use the mobile panel for a long period of time, then please remove the battery from the device before storing it switched off. Otherwise, the battery indicator on the Mobile Panel might show too low a value or the "Empty battery" vibrating alarm might be set off even though it might still be possible to operate the panel without recharging.
If your device's battery indicator shows that the battery is almost empty although the device's operating time is still quite a way under 4 hours, then fully charge the battery and then during the next operating time let the battery empty completely (!); this is the only way for the battery to run through its "learning cycle". Repeat this procedure if the battery indicator is still incorrect.
Fig. 01 - Battery of the Mobile Panel
Battery, Accumulator, Charging characteristics