Latitude e6420 Battery

Hey!

I've been using my E6420 since a couple of years, but I recently bought a new battery (6-cell 60Wh) original from dell. I notice that the battery only lasts for about 1-2 hours only browsing with power-saving profile and also about 15% brightness.

-I installed the new 1909 Win10 update but it didn't help much.

-I'm using Microsoft Edge (which is consuming 33% and 28% in background)

-I've tried disabling Nvidia drivers (thus only running with integrated video card)

-Tried disabling Intel turbo-boost from BIOS, didn't help (at least not a noticeable change)

-BIOS tests says my battery has a health of  85%

-Tried disabling all my start-up programs (which were not many) that I don't need.

-Updated every single driver, SupportAssist says there is no driver available, also did its tests and passed them all.

-BIOS is the latest, A26 I think.

I hope you can help me find a solution to this!