2017 Macbook Pro (Base Model) Battery Draining Suddenly
Does anyone know why my battery is draining in 3-4 hours with normal use on the 2017? This was the case with a refurb that I bought a few months ago which I returned because no one at the store or over the phone seemed to have a clue as to what was causing it. Got this one, and for the first 1-2 weeks the battery lasted 9-10 hours. Then one day, 4-5 hours. Now 3-4. Not even playing video-just normal web browsing. The refurb had the same issue from the moment I opened it. I upgraded my mother's 2015 Macbook air to Mojave and now it is having the EXACT SAME ISSUE with the battery. The performance is much slower too, as it is on my 2017 pro, and the bootup is twice as slow on both laptops. Does anyone have any clue what's causing this? Any insight would be greatly appreciated :)
P.S: I ran disk utility. Everything is normal. Then I reinstalled Mojave, and the issues are still exactly the same.
MacBook Pro 13", macOS 10.14