Battery life on Nexus 5 is awful

I'm getting around 1 to 2 hours on screen time with messenger, clash of clans, web browsing. Tat's all. There isn't much apps draining power, actually the problem is in the battery statistics show I only used 57% total. I have recently bought a new battery but it's still awful. I'm requesting for help cause I might be forced to purchase a new phone if this issue persists. I'm also running Marshmallow, 6.0.1.