Airnote's battery discharged quickly after 5V USB disconnection

Recently I have observed an abnormally fast discharge rate of my Airnote’s battery after the disconnection of the 5 V USB external supply, as shown in the attached screenshot:

Within about 5 h from the 5 V removal the battery voltage dropped down to 3.5 V

As shown in the following screenshot, the 5 V USB wall-plug supply remained connected during the last 18 days, hence I expected a fully charged battery ensuring a very long working time.

Is there something wrong with the battery? In case I could replace it.

Thank you very much and best regards,


Hi @AlberTO
This looks like a deffective battery. We would like to do some analysis on the device as well as replace your existing device. I will follow up in a DM with more info.

Thank you very much, Greg!