Hi; November 22, "upgraded" to Win 10 from Win 7. I too noticed, on my Acer i7 Aspire laptop today, on December 2nd, that my battery drains down at least a third faster on Windows 10, doing similar things that I would do on Windows 7. Yes, it has a Battery Save feature that dims the monitor when it gets below 20%, etc, but it's pretty obvious something is draining the battery faster under new OS versus old. I have to believe there is allot more overhead with "App" features versus Win 7, which is mostly a shell. Win 10 has some features that I find "fun" or "appealing", but it is not this big whup upgrade that makes me click my heels with joy.
A second problem is that the battery notification icon will disappear completely and I have to do a "Find New Hardware" in Device Manager to make it reappear. I added a batch file to run Devcon.exe to have it command line run "Find New Hardware". I saw that some folks, in 2012, had this issue and a Bios upgrade resolved their problem.
So I really don't have a solution, but I can see this might become a case of bandaiding Win 10 versus going back to Win 7. I'm seriously considering going back.