I'm confused. It seems that your are concerned about battery loss when you are not using the phone. What kind of performance are you getting during normal usage? If it is sitting unused for 8 hours in airplane mode, why not plug it in and charge?
It looks like you are at 42% after being off the charger 21hrs. That doesn't sound like awful battery performance. Why wouldn't you plug it in when you are not using it like while sleeping? Assuming you sleep at least 5 or 6 hours a night, you should never get below 70%. Sounds like plenty of battery for your usage pattern.
I understand your confusion.. as I wrote before, this isn't my usual usage pattern. from the minute it hit 100% I tried my best not to use it as much as I usually do.
and I can't connect it to a charger whenever I'm not using the phone because most of the time I might not get access to a charger, plus I really don't want to rely on it.
perhaps I didn't explain myself properly. The battery life isn't THAT bad. it's great compared to my previous phone.
the problem comes when I compare my battery life to another V20 or a G5. while my phone loses lets say 15% while idle for 20 hours, the V20 my sister is using will lose about.. 5%? the G5 my friend is using will lose 3%?
it just makes me think that maybe something IS wrong with my phone. I could manage a whole day if I try not to use it as much (idle whenever I can, use nothing but WhatsApp, screen at lowest possible brightness whenever I can, data off and battery saver whenever I can), but why won't I just use it like I normally do and get the same battery results?
EDIT- I'll try to use the phone like normal and post the stats. maybe that will help