Surface Book 2 battery drain whilst off

You are spot on.

First time i found rapid battery drain overnight from 90 to 0% is when i left usb reciever of wireless mouse.

Just day before yesterday i found rapid battery drain overnight when i left memorycard via card reader. 

Yesterday, i removed usbcard reader and found overnight drain of 4% despite shutting down.

Yes, I concur: Microsoft should show us some customer support and at least let us know what is up, and what the future of this looks like. And yet, after no less than 15 pages on this thread, no official answer was ever given. Not even a single message from a MS representative to acknowledge that there is a problem, not once, not ever. I don't know about you, but to me it decidedly seems like MS know all too well that their product is defective, and they are hellbent on not admitting it. I'm absolutely convinced that there is no simple solution to this fault, because it is due to some design error somewhere. MS are/were aware of this, and they proceeded to sell a defective machine nonetheless. We will never receive an answer from them: it would mean that they'd have to admit their (extremely serious) mistake.

Hello, the suggested method did not work for me: after two days of keeping the Surface shut down after having completed a full charge (and with the shift button technique), I've just turned it on, and the battery level was 73%. I don't think this problem can ever be solved, and I am more and more convinced that it is a hardware fault that cannot be corrected via software.

Thank you anyway for your kindness.

I have the exact same issue.

There is no doubt it is annoying on such an expensive device as this. It is even more annoying as I rarely use the device as I primarily work on my desktop with 3 4k screens, and find the laptop to be restrictive. BUT, when I need it, it is always low on battery, so I am left with a device that that is almost useless.

I have resorted to storing it plugged in, and get in the habit of plugging it in after use. Sucks but better than not having the computer I need on a service call, or for a meeting when I need it.

Microsoft should show us some customer support and at least let us know what is up, and what the future of this looks like.

Okay, after one month usage, I have to say the replacement SB2 has exactly the same battery drain whilst shutdown issue. 

I've reported back the issue and advised to go through the same process as for the original device, which I rejected. I asked them to collect the device and do as much tests as they want in their lab and return a not faulty device.

Today, I received an email offering a replacement again and I responded that I don't want to go throught the same cycle unless Microsoft can gurantee that the next replacement device performs as per their specs. Unfortunately, I don't believe thay can. Otherwise, they should've already answered this thread by now.

I'd swear that more of my counted battery cycles have come from this draining while off than from me actually using it on battery.