W3-810 battery drains when turned off (full shutdown)

I got a W3-810 a week ago. So far it is great except for a problem with the battery; it loses about 1-2% per hour when shut down--most, but not all of the time; see below.

As far as I can tell, all drivers are up to date.
As the manual recommends, I deactivated Fast Startup so that when I use Shut Down from the Win 8 Charms bar, it should do a full shutdown, not a hybrid.
-I ran a command from the Powershell that confirmed the last couple Shut Downs were indeed full.
The relevant info from powercfg /battery info is as follows:
2015-09-11 20:51:32 Suspended 64% (did a full charge up with system off; charging light turned blue)
2015-09-12 12:00:48 Active Battery 81% (loss of 19%!

2015-09-12 14:22:00 Suspended 64% (did a full charge up with system off; charging light turned blue)
2015-09-13 08:23:40 Active Battery 83% (loss of 17%)

2015-09-13 13:44:00 Suspended 76% (did not charge)
2015-09-13 18:19:11 Active Battery 74% (<--2% seems like a reasonable amount)

2015-09-13 20:13:19 Suspended 72% (did not charge)
2015-09-14 08:06:23 Active Battery 71% (<--1% again good)

2015-09-14 13:20:50 Connected Standby Batery 65%
2015-09-14 17:07:06 Active Battery 65% (<--excellent for sleep mode)

2015-09-14 17:18:00 Suspended 63%
2015-09-14 20:07:20 Active Battery 57% (<--6% loss in less than 3 hours, not good)

To me this variation does not seem reasonable; I never know what my tablet's power is going to be like when I turn it on.

I have searched all over the internet for help with this problem but have not come across anything useful. So, I am turning to this forum for a hopefully easy & quick fix. Thanks in advance for any assistance you can provide.

Accepted answers

billsey

I believe the issue to be the battery charge reporting mechanism, not that the battery is discharging. Try going through a couple of full charging cycles (charge fully, run on battery until it shuts down, then charge fully again) to get it to recalibrate and see if that fixes it.

All comments

sdhindia

Okay, this is so strange:

I did at shut down at 52%, didn't plug it in to charge. Seven hours later when I turned it on, it was still at 52%.
I then charged up to 100%, shut it down. Turning it on 3 hours later, battery is down to 82%. That's -6% an hour.

Does anyone have any idea what is going on?

billsey

I believe the issue to be the battery charge reporting mechanism, not that the battery is discharging. Try going through a couple of full charging cycles (charge fully, run on battery until it shuts down, then charge fully again) to get it to recalibrate and see if that fixes it.

sdhindia

Thanks, I'll try that. Question: the battery settings are currently set to shut down the system when it gets critically low, 5 or 6% or something. Should I deactivatet that and let it completely run out? I'm reading conflicting information about that potentially damaging the battery.

billsey

Leave it at the defaults or tweak it a little, don't let it get all the way to 0%, because it's not too far below that where it won't recharge, and you really don't want to go there. Smiley Sad Especially since if it's not calibrated it could be reading higher than it really is at low levels.

sdhindia

After a few days of testing, that seems to have done it! It's reporting negligible to insignificant losses on both Sleep and Shutdown. Thanks for your help!