I am currently using a HP Spectre x360 13-inch (2017) laptop. Used it since August 2017 and now its battery can only last less than 30 minutes unplugged even when fully charge... :( It's basically a PC to me now. I made the classic mistake of unplugging my charger so frequently that it increases the charge cycle.
Some battery-saving tips I should have done is to keep it charged longer to save cycles and only unplug the charge if I really need to. Also, get a laptop cooler to keep the battery cool when the laptop is overheating. I think I heard that too much heat can damage the battery or something. And set the laptop to Battery Saver mode. That increases the battery life for about 20% for me.
For my laptop in particular, I think using Google Chrome is a huge battery drainer. I also used to keep a lot of tabs open. Big mistake haha.