My laptop battery drops 50% to 0% suddenly

[mylaptophelp]

My laptop battery suddenly drops from 50% to 0%. What should I do? What are some possible causes? Is changing battery the only solution? This problem happened pretty recently. 

[ub6424 · Accepted solution]

Hello @mylaptophelp 

Sorry to hear that you are having problems ... and I would like to help you.

(1) Install/Update

HP PC Hardware Diagnostics UEFI

7.6.2.0 Rev.A

42.7 MB

Jun 12, 2020

Download

(2) Test your hardware/battery using the HP PC Hardware Diagnostics (UEFI)

https://support.hp.com/us-en/document/c04499777

See how it works:

https://www.youtube.com/watch?v=14GKIpGPNRM

(3) Please report your results

[erico]

I would recommend that you use Windows own Battery-Report utility to make an informed decision as to the current state of your battery.  I wrote a knowledge base article that describes how to access the report. The article is available at the hyperlink below this line.

https://h30434.www3.hp.com/t5/Notebooks-Knowledge-Base/Is-your-notebook-plugged-in-and-not-charging/...

A battery which has the significant capacity drop at 50% is actually unlikely tor be able to run the HP PC Hardware Diagnostic Battery test. That is because what you see as the current 100% is not accurate.

[ub6424]

Dear @erico 

I find your contribution valuable, thank you very much.

In this case, it could be a battery with many charging cycles. If it is not cleanly calibrated, it makes it even harder to analyze. It is very likely that the battery needs to be replaced. 

Let's see what results HP Diagnostics UEFI and the Windows variant deliver.

[mylaptophelp]

I have done those, but no test found any problem. They all said my battery is fine... Should I have done this while the laptop is unplugged?

[ub6424]

Do the following trick ...

(1) Open the windows <device manager> and uninstall "Microsoft ACPI-Compliant Control Method Battery" 

- Right click on "Microsoft ACPI-Compliant Control Method Battery"

- Click "Uninstall device"

- Confirm your choice if you see a popup notification

(2) Shutdown notebook

(3) Disconnect charger, press and hold power button for 30 seconds.

(4) Start notebook and enter bios (ESC/F10) and let it stay there or run HP Diagnostic Test loops to drain battery (don't start windows operating system AND don't connect charger !) until it is switching off automatically !

Note: If you unexpectedly started Windows, you have to repeat (1) (2) (3)

(5) Plugin charger and wait until battery is fully charged (don't start windows operating system !) and check charging led.

(6) If you do have no charging led, wait at least 2 hours ...

(7) Start notebook and log in to windows. Now windows acpi battery device and battery management system are synchronized. It should show 98-100% battery level.

(8) If battery level is too low and it's loosing capacity too fast, it has to be replaced !

(9) Please report your results

[mylaptophelp]

I am not sure what you mean enter bios. Should I press esc and f10 immediately? Or should I press esc or f10 immediately? Or Should I repeatedly press esc and/or f10?

[ub6424]

Detailed description

Enter BIOS

- Turn off the computer and wait five seconds

- Turn on the computer, and then immediately press the [ESC] key repeatedly until the Startup Menu opens

- Press [F10] to open the BIOS Setup Utility

[mylaptophelp]

Ok. thank you. I have done what you said. And I checked the battery full capacity. In 2019, it was 56199 mWh, but now it is 34495 mWh. Should I replace the battery? Can I do it at home?

[ub6424]

Hello @mylaptophelp 

The battery capacity has suffered after time, that's how it is with batteries. As is well known, they do not last forever. Individual cells break down and so on... Well, check how long you can work with a fully charged battery. If that is okay for you, you can still use the battery. But I would change it soon, if you lose too much capacity.

Your question: You can change the battery at home. Craftsmanship is required.