10% battery loss just restarting phone

[UnfixedPyle]

I know there are lots of threads about battery life. I am actually quite happy with my L920's battery, especially post Portico. My general use has me plugging in at bedtime with 40-60% depending on what I did that day. There is one weird thing though. If I turn my phone off and back on it shows it loosing exactly 10% every time. I have some places at work where I can't carry my phone, so I would normally just shut it off as the lock box it goes into kills the signal. I have resorted to airplane mode (which is just as easy) because of this, but was wondering if anyone else was experiencing this. Or, is this just another example of how screwed up the battery meter is on WP8

 

[rockstarzzz]

Screwed up battery meter. I've had this before.

 

[santillanavila1993]

Maybe it is the battery meter but every time I restart my phone I get 2-3% battery drop. I assume its the power needed to power up everything. 10% seems excessive.

 

[InnocuousScreenname]

As much as I do love this phone. my Lumia 920 has serious battery calibration issues. I never trust the battery percentage. A few days ago, I had severe battery drain, and my phone was dead in about ten hours (which is very unusual for me). After it went through auto-shut down, I booted it back up again, and my battery had 28% left. The problem seems to be exacerbated by wireless charging.

I've just come to accept that if you charge via USB, or wall charger, battery percentage is pretty much +/- ten percent of what's showing in terms of battery charge. If you're in the habit of wireless charging, there's a much wider margin for error.