Laptop battery drains unexpectedly while shutdown

Laptop battery drains unexpectedly while shutdown.
Article:  Windows 10 2021.04.16

Problem:
When a Windows 10 / Windows 11 laptop is shut down (not Sleep, not Hibernate), the battery meter shows excessive draining, visible even after a short over-night downtime.

This is a vexing problem, affecting many brands of computers.  I suspect multiple, simultaneous issues are at play.  Solved using a combination of Solution 1, Solution 2, and Solution 3. 

After much researching and snooping, I was surprised few of the sites mentioned a rather obvious Control Panel setting in Windows 10.  This was the real solution (#3) to the problem.  I joked with a friend, "I've never read this screen before..."

By design, if the laptop is in "Sleep" mode, the battery drains.  This article is only concerned about draining in "Shutdown" mode and assumes the laptop is not connected to AC power.


Solution 1:  "Disable Charge (USB) in Battery Mode"

If this is a newer laptop, it likely has the ability to charge a USB port (charge external devices) during low-power states (standby, hibernate, or power-off).  I believe this uses power to monitor if the port is active or not.  This is known by various names, such as USB Passthrough, USB External Charging, PowerShare, etc. 

A.  Boot into the laptop's BIOS Setup screens.  Steps vary by manufacturer or model.
      Often press F1, or F2 at the hardware boot banner (if displayed).
      Some vendors expose this setting in a settings screen. 
           With Lenovo, see the Vantage program.

B.  Note the BIOS version. 
      Needed by Step 2.
   
C.  Regardless of the BIOS version, continue:

      In the BIOS menus, locate the USB menu 
      For Lenovo:  BIOS, Setup, Config, USB

     Turn off:  "USB:  Always On USB"  or similarly-named feature.

D. Save BIOS changes with (F10)  Steps vary by mfg.

Drawback:  You won't be able to charge your cellphone, while connected to a powered-off laptop.


Solution 2:  BIOS Update

Research the laptop's vendor support page for the current BIOS version.  Even with a new laptop, the BIOS is likely older.   Early Intel motherboards had power management flaws.  

A.   BIOS update steps vary by manufacturer. 

With Lenovo, the BIOS can be updated through the desktop "Vantage" program.    

See "Recommended Updates" or download the BIOS from the support site.  BIOS updates are specific to your machine.   If downloading by hand, be sure to locate the correct machine.  The Vantage program's update makes this easy. 

With Dell, use your Service Tag and their website to download the latest BIOS.  Other vendors use similar techniques.

Solution 3: Power Button Settings and Turn Off Fast Startup

This is the key to this problem.  By default, many laptops (defaults) to "When I press the power button", the laptop goes to sleep!  Sleep is not the same as shutdown -- and sleep draws power.

A.  Open Power Options
      (this setting is not easily found in the Windows 10, 11 Gear icon; Use the Control Panel)
      Click Start, type "Control Panel"
      Select "Power Options"

B.  On left-nav, select link "Choose what the power buttons do"

C.  (If you are running in a non-administrative mode)
      Click center link, "Change settings that are currently unavailable"

D.  Continue with this IMPORTANT step: 
      Change the power button's behavior from "Sleep" to "Shutdown", as appropriate.
      Particularly with the "When I press the power button", both battery and plugged-in

      This was the key to the problem.

Incorrectly Set as "Sleep"

By default, your setting may be set to
"When I press the Power Button, go to Sleep" - where Sleep draws power. 

I recommend these changes:

* When I press the Power Button   On Battery:  "Shut down"
   When I press the Power Button   Plugged in:  "Shut down"

* When I close the lid:                    On Battery:  "Shut down"
   When I close the lid                     Plugged in:  "Shut down"

Why change in four places? 
Imagine you are plugged into power.  Then you shut the lid and stuff the laptop in a bag to catch your flight.  As illustrated above, the laptop goes into a Sleep-state, not a power-off state.  You'll forget, and the next day at your conference, half your juice is gone.  Set these to shutdown.

"Sleep" is still available on the Start Menu.  On some laptops, a long-press on the Power button is a shutdown, a short-press is Sleep.  This recommended change overrides this behavior.  How to tell which state you are in?  Sleep is a soft-boot and you will not see the hardware or BIOS screens.

 
E.  Finally, consider this change on the same screen:  "Fast Startup"

Numerous sites recommend unchecking "[ ] Turn on fast startup" (turn off, even though 'recommended').  Lenovo recommends turning this off for this problem.  I am not doing this myself.

Comment: There are reasons to use and not use "Fast Start".  See this article for a description of the feature:  The Pros and Cons of FastStart).  

But in relation to this article's problem (power-drain), this switch made no difference with the power-drain of a sleeping computer.  If checked, this consumes a small amount of extra processing during shutdown, but after shutdown, the PC is off and consumes no power except for a 1 or 2% drain per day that all rechargeable batteries have.  

Other Solutions - Battery Gauge Reset:

Not recommended:  Run "Battery Gauge Reset"

On an older computer (battery), the battery's daily-life-expectancy can change from what the battery-level meter expects.  By fully-charging, then fully-discharging the machine (with no sleep, hibernation,  power-savings, or shutting down), Windows re-calibrates the meter with the battery's actual abilities.  Lenovo provides a battery re-calibration program just for this purpose, but you can also easily do this by hand.  

Contrary to other web sites, this actually does re-calibrate the battery meter, but this will not fix an unexpected drain.  In other words, this is a waste of your time.  I ran a re-calibration on my new computer and it took 23 hours!  In the end, the battery "adjusted itself" from 44.72 watt-hours to 44.50 watt-hours, and the draining continued.  Older batteries might benefit from this, but this only fixes inaccurate power % readings, not premature draining.  The BIOS and Powerbutton-changes, steps 2 and 3 above, were the real solution.  

Not recommended for this problem:
A.  With the Lenovo, launch the Lenovo  desktop "Vantage" tool. 
      (Start, Run, "Vantage")
      Other vendors may have similar software.

B.  (Scroll past all the advertisements and premier enrollments),
      locating "Quick Settings".  Click "More Settings"

C.  Locate "Battery Gauge Reset"

This program walks you through a series of steps, where power is plugged in, then the laptop drains the battery (even with power), and then re-charges the battery.  This takes a horribly-long time. 


Disable Wake-on-LAN

In BIOS, disable Wake on LAN  (allows a network packet to boot/reboot) the PC.  This is only needed in a corporate environment and your laptop likely has this already disabled.

This is not likely a cure for this problem, but is worth looking at.


Related Problems:
Battery Meter fluctuates and is wildly inaccurate.
Battery meter unreliable. Battery meter erratic.   Battery meter unreliable.
Battery meter fluctuates.   Batter meter wildly inaccurate.  Battery meter wrong.

Many users, with many brands of computers (possibly all with Intel Motherboards) are reporting a problem where the Windows 10 System tray reports wildly-inaccurate "time to live" on the battery gauge.  

For example, my new Lenovo E14, on a fully-charged battery will report 6 hours of time left, then a few minutes later, it will say 2 hours, then a few minutes later will report 11 hours.  The battery is not malfunctioning, nor is the battery near discharge. 

I spoke to Lenovo about this:  "We have never seen this problem before."  They offered to repair the machine, but I declined, thinking this is really a software problem.

Clearly lots of people are seeing the problem and from what I can tell, there is not an obvious solution.  There is, however, a registry hack which is acceptable.  This hack hides the "3.5 hours remaining", leaving only the battery's percentage-left.  This does not fix the problem but it does hide the inaccurate appendage.  Changing from "89% (4 hours remaining)"  to "89%".

High-level details:
HKLM\System\CurrentControlSet\Control\Power
EnergyEstimationDisabled       = dword: 00000001
EnergyEstimationEnabled        = dword: 00000000
UserBatteryDischargeEstimator  = dword: 00000001

You will probably have to manually create the EnergyEstimationDisabled key by hand (a Dword).  Step-by-step on how to edit the registry are not in this article and I assume you have skills in this area.  If not, leave a comment and I consider expanding this article.

Close the Registry Editor.
Restart the computer

Hover mouse over battery meter.  Formerly, it would say:  "89% (2 hours remaining)".  Now it will report just the percentage "89%".   This is good enough.

2021: If I had a suspicion, this is a problem with Intel Motherboards and the "Intel Management Engine" drivers.  Updating to Lenovo's approved version, and then updating to Intel's latest version, which is newer than what Lenovo has tested, has not yet resolved the problem.