why is my samsung S5 battery draining so fast, and running so slow?

[AC Question]

runs very slow opening apps or websites...and battery life is really poor and it used to be pretty good

 

[belodion]

What do your battery usage stats indicate as the main users of charge after a drain from 100% to about 40%? https://forums.androidcentral.com/showthread.php?t=409154