This is a great tip from 9to5Mac and while the name implies Apple, iPhone, and all things iOS, it applies to Android devices as well. Get rid of your Facebook app if you want your battery life to last longer. And I've stop using the Facebook app on my mobile devices for years and have not suffered the battery debilitating drainage that many millions have reported and suffered from.
When absolutely, I do download it on the quick and do what I need to do and delete the sucker again. And surprisingly, my friends on Facebook have not disappeared and they continue to exist in the mobile version of Facebook in my browsers.
And the browser version of Facebook works just fine for addicts. Think of it this way, you can stay on Facebook longer and satisfy your addiction with the browser version than if you were using the Facebook app. It's a win-win if you're that hooked.