My SP6 dies at around 30 % battery - why?

[Mastiff]

I don't mean going into Sleep or Hibernation. It just suddenly cuts out while I'm reading my online newspapers at night (which is when I use the battery, the thing is connected all day, when I'm working). This takes around 3-4 hours of just web browsing, nothing else. And when I connect it to the docking to get it starting again, the battery will show around 34 %. But it still won't power up withoug a power connection. Anybody knows what the heck is going on here?

 

[sharpuser]

You may need to exercise your battery. When a battery is connected most of the day and night, it may degrade the total capacity. But repeatedly allowing it to discharge to just above the 30% shutdown, charging again, then allowing it to discharge again, etc. should drive that shutdown number below 30%.

This is my experience with both of my Surface Book 2 units. They currently shut down at about 8% -10% battery remaining, but that is because I exercise them, despite generally being plugged in at night.

You can find lots of information about exercising laptop batteries on the Web.

 

[Mastiff]

Aha, thanks! Worth a shot. But it's not connedted at night, only from 8 to 16-22 (depending on the workday), and then taken out. But I will find a way to wear it out. I'll put logging on it so I can see when it stopped and on what percentage.

 

[sharpuser]

From: Caring for your Surface battery (microsoft.com) :
When using your device, make sure the battery drains below 50 percent regularly. This will help minimize deterioration of the battery cells.

 

[Mastiff]

I do. I have drained it to around 35 % almost every night, with the hours of surfing (full brightness, full speed on the CPU, power saving is for wimps...). I did a Prime95 just now (in case you're not familiar with it it was very much used in overclocking when that was still a big thing, sort of making your CPU run a marathon in 100 meter sprint speed), and it died within 90 minutes! With the battery showing 40 % or so. Not very encouraging, but I'll do some more of those this week and see if somethign happens.

 

[Turbo4AWD]

From: Caring for your Surface battery (microsoft.com) :
When using your device, make sure the battery drains below 50 percent regularly. This will help minimize deterioration of the battery cells.

Oh s***....I need to start doing this. I mean I let it get to 40% sometimes...but not regularly. Good to know!

 

[wpcoe]

I only found out within the last year that there's a setting in BIOS that lets you restrict battery charging to a maximum of 50%. That's intended for folks like me who use their Surface Pro like a desktop computer, i.e. plugged in for 90% of its use.

 

[Mastiff]

I have now done this everyday for almost a week (by reading my regular news in bed at night and then leaving the Surface running, standing up on the floor with the screen towards the wall), and it has not gotten any better. Actually last night it had stopped on around 40 %, not 30! Is it because I need more time doing this, or is the battery really dead? I have more than two years left on my warranty, so the only problem by sending it in for repair is that I need to buy another one to use in the meantime (I run my own translation business and can't be without a computer that can be hooked up to my Surface dock, which has all my necessary stuff like two monitors, dongles for different translation programs and so on). But I can probably find a used one. It would be nice with an SP 7 Pro+, with a replaceable SSD...

 

[sharpuser]

Battery needs to be replaced. You gave it a good try. Good on you for buying the warranty. I hope you can find a computer to use while yours is getting repaired

PM sent

 

[Mastiff]

Yeah, I think I have one on the Norwegian version of Craig's List, thanks!

 

[Turbo4AWD]

I have now done this everyday for almost a week (by reading my regular news in bed at night and then leaving the Surface running, standing up on the floor with the screen towards the wall), and it has not gotten any better. Actually last night it had stopped on around 40 %, not 30! Is it because I need more time doing this, or is the battery really dead? I have more than two years left on my warranty, so the only problem by sending it in for repair is that I need to buy another one to use in the meantime (I run my own translation business and can't be without a computer that can be hooked up to my Surface dock, which has all my necessary stuff like two monitors, dongles for different translation programs and so on). But I can probably find a used one. It would be nice with an SP 7 Pro+, with a replaceable SSD...

Also, you can run the Battery Diagnostics built into Windows 10 and it will provide an accurate reading on your battery's life.

 

[Mastiff]

Thanks, I didn't know about that one! It does seem like there's not much left:

2020-12-28 - 2021-01-04	35 970 mWh	45 000 mWh
2021-01-04 - 2021-01-11	38 910 mWh	45 000 mWh
2021-01-11 - 2021-01-18	38 910 mWh	45 000 mWh
2021-01-18 - 2021-01-25	34 312 mWh	45 000 mWh
2021-01-25 - 2021-02-01	35 786 mWh	45 000 mWh
2021-02-01 - 2021-02-08	36 722 mWh	45 000 mWh
2021-02-08 - 2021-02-15	36 098 mWh	45 000 mWh
2021-02-15 - 2021-02-22	35 915 mWh	45 000 mWh
2021-02-22 - 2021-03-01	33 820 mWh	45 000 mWh
2021-03-01 - 2021-03-08	33 820 mWh	45 000 mWh
2021-03-08 - 2021-03-15	34 648 mWh	45 000 mWh
2021-03-15 - 2021-03-22	33 765 mWh	45 000 mWh
2021-03-22 - 2021-03-29	33 795 mWh	45 000 mWh
2021-03-29 - 2021-04-05	33 299 mWh	45 000 mWh
2021-04-05 - 2021-04-12	35 220 mWh	45 000 mWh
2021-04-12 - 2021-04-19	36 749 mWh	45 000 mWh
2021-04-19	37 998 mWh	45 000 mWh
2021-04-20	36 204 mWh	45 000 mWh
2021-04-21	36 186 mWh	45 000 mWh
2021-04-22	36 100 mWh	45 000 mWh
2021-04-23	33 522 mWh	45 000 mWh
2021-04-24	36 944 mWh	45 000 mWh
2021-04-25	35 811 mWh	45 000 mWh
2021-04-26	20 017 mWh	45 000 mWh