The battery life is indeed a bit shorter than originally promised by reMarkable. As this is, however, largely determined by the software, we can keep hoping that this issue will be resolved with one of the hopefully soon coming updates.

However, if your battery is draining significantly faster, you might try the following steps:

1. Charge it fully (If not sure, keep it on charge over night)
2. Switch your device completely off - it should say “Your reMarkable is powered off”
3. Switch it on again

The complete restart after a full charge should help with battery capacity calibration and will terminate any rogue processes.