Microsoft Surface 3 battery charging time

About 4 hours from less than 10% battery. That's about one hour slower than my Surface Pro 2 with its custom charger at the same level.

...

I've always used the charger and cable that came with the Surface 3 and I have not seen any terrible charging times. I went from 5% to full in under 4 hours yesterday. I wasn't using the Surface during charging, so I'm sure that helped. But 4 hours for a full charge seems acceptable. Is it the fastest charging device I own? Definitely not. But I don't think it is that slow to be considered an issue.

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Finally drained the battery on my Surface 3 today (wouldn't even turn on, battery symbol would flash on the screen). Charged it for 2 hours 45 minutes and was at 85%, took an additional hour to get to 100%, so roughly 3 hours 45 minutes from dead to full charge while the Surface is turned off. Not too bad at all IMHO.

source: https://forums.windowscentral.com/microsoft-surface-3/355747-surface-3-battery-life-charging-times.html

Battery report

Overigens kun je een rapportje trekken van je accugebruik. In een 'elevated' command prompt geef je volgend commando:

powercfg /batteryreport /output "C:\battery_report.html"

of zelfs een uitgebreide studie:

powercfg /sleepstudy /output "C:\sleepstudy.html"

In praktijk

laadtijd	laadniveau
3h 45m	92%
4h

96%-95%_78%

datum	3h	7h30	18h30
26/08/'19	100%	95%	77%
27/08/'19	100%	97% (6h20)
28/08/'19			79%
30/08/'19			80%

'Over time', de laadtijd neemt niet toe, maar het 'dischargen' gaat sneller.

datum	3h	18h37-19h28
17/01/'21	100%	65%
18/01/'21	100%	69%
19/01/'21	100%	68%

So I've added a scheduled task that shuts the tablet down at night.

timestamp	capacity remaining
22/01/'21 18:38	97%

A side-effect is that upon restart, the wifi connection is not always re-established. So I wrote a small startup script that checks if the connection is established, and if not, establish the connection:

ipconfig|find/i "123.456.789." && rundll32 || netsh wlan connect name=... ssid=...

This is a good solution, but once in a while, the laptop has been active during the day, e.g. after patch Tuesday:

• 11/02/'21 05:19:11: 94%
• 11/02/'21 18:17:53: 68%

I found the following article, https://www.reddit.com/r/Surface/comments/40cq4i/surface_3_battery_drain_and_sleep_study/, and have now:

• disabled the 'wake by pattern match' setting of the wireless adapter
• disabled the scheduled task that shuts down the tablet at night

I'm curious what the result will be.

• 12/02/'21 18:02:21: 70%

That's a lot of drain. So I'm going to

• re-enable the 'wake by pattern match' setting of the wireless adapter
• re-enable the scheduled task that shuts down the tablet at night (23.30) and finetune it:
  • to repeat the task every 7 hours
  • for a duration of 8 hours
  • stop all running tasks at end of repetition duration

I suppose this will be of some help.