Airnote's battery discharged quickly after 5V USB disconnection

Airnote
1

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:

01_External 5 V removed_annot
01_External 5 V removed_annot903×327 36.9 KB

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

Note:
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.

External 5V supply period
External 5V supply period909×896 103 KB

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

Thank you very much and best regards,

Alberto

2

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.
Cheers,
-Greg

3

Thank you very much, Greg!

Regards,

Alberto