That is not a thing. The battery percentage is basically the battery voltage. The gauge will start to show wrong values when the battery is old because the voltage itself isn't a good way of comparing the real capacity anymore. It might show 4.2 volts like it's fully charged but as soon as you put a load on it it will tank to half, for example. This only happens with old batteries.Like (many?) others, I have had one occurrence of dead battery overnight on the R2-II. I’m still waiting for another occurrence to investigate a little more, but it hasn’t happened…
Then it hits me: could it simply be a self-calibration feature of the battery gauge? If a “fuel gauge” chip is used, full discharges are needed to calibrate the chip, either as they happen in use, or forced by the OS, once, or periodically.
The “(show) battery percentage display” setting may have something to do with this—it’s “on” on my R2-II…
Some smartphones have a way of calibrating themselves when you do a full cycle, but they don't force you to do the cycles by telling you the battery is dead. And i doubt a device like this has any kind of calibration like that.
Also, i already contacted hiby with the problem. If that was the case, they would have informed me but they just told me to do a factory reset to see if it helps and if not, to send it in for repair. They clearly don't know what's going on.
This is also not a thing. The battery has protection (if it's working), it literally won't let you charge more to protect itself.It is also possible for the meter to read 100% too soon after charging without the R2II being fully charged. I haven't experienced the sudden discharge since I started "overcharging" it, i.e. charging it longer than the full charge color indicates.
If by any way the protection is not working and it it indeed still charging the battery even when it told you it if full, best case scenario your battery will be damaged in a month, worst case, it will burst in flames.
Anyway, there is no real advantage in leaving the cable connected after it's charged. It will slightly degrade the battery was well. As soon as it's full it will stop charging, some minutes later it will drop to 99% and then charging will kick in again and keep doing forever. This is the reason why people don't recommend you charge your smartphone overnight.