Surface Book 2 battery drain whilst off

You assume correctly.

I'm cynical, I know. But I refuse to believe that a defect as blatant as this could make it through testing. I'm still convinced that it would be relatively easy to fix, if only they had the will / interest.

I've been having the same issue since I purchased my Surface book 2 in August of 2018. I just turned on my laptop it was fully charge a couple days ago and turned off. I turned it back on , battery 2 was at 85%. When I removed the screen and attached it battery 2 went from 85% to 65%!!  I paid $3000 for this laptop and this should not be an issue with many of these laptops. I contacted Microsoft in September 2018 and also a few months ago. They stated it was normal for the SB2 to drain when shut down, between 3% to %5 daily because it needs this feature to boot up quicker. Later they stated it was a hardware issue after I went through all the troubleshooting. The first time they were willing to give me a full refund or let me send in my unit and replace it with a refurb. The 2nd time a few months ago they were going to replace it with a refurb. You pay $3000 for a brand new laptop and they want to replace it with a refurb? That's insane! They also only send you a pre paid shipping label no box or packing. You have to pack it and find a box! I had to replace a gaming console with Sony a while back and they shipped me a box and packing. That is how a real company takes care of it's customers! You are without a laptop until they receive your unit and ship the refurb.  I will never again purchase a Microsoft Surface!! I will probably look into purchasing a Mac in the future. We should all see if we can contact a law firm? Maybe we have a class action lawsuit!!

Yep I truly hope someone closer to the US law circle can file a lawsuit for this. That could save millions of souls.

This issue happens in my SB2 also. Basically if I leave it off for some time when I come back it might have the battery 2 drained to 85%. The problem is that for it to start behaving properly I have to discharge it and then charge it back, for it to have the normal battery behavior. Based on my daily use of the Surface this usually happens to me at least once a week.

I have the same problem. I got a warranty replacement and that process took so long that I bought a different laptop. This was my first non-MBP in a decade and I wanted to love it so badly. After 3 weeks of back-and-forth with Microsoft I had to buy a replacement laptop, and I went back to what I knew.

So when this one finally got to me, I turned it on to check that it worked and then turned it off with a full charge. It has sat for a couple weeks and I recently turned it on take pictures to sell it and it was completely dead. 0% | 0%.

I will never in my life purchase another Surface Book product.