Its been awhile since I've used android but I decided to switch from iPhone to Samsung and I bought the s10 plus but I'm having some doubts about the phone. I love it but the only thing about it is the battery life. The battery life hasn't been terrible but for some reason I feel like it drains quicker that it should. My normal day to day use of the device it moderate as I'm not using it constantly, only to check email or text messages and to listen to Spotify here and there but I feel it drains more when the phone is on stantby. I charge the phone before leaving for work the next morning from 50 percent to 100 percent and after having it off the charger for 8-9 hours my battery life at the end of the day tends to be around 70-60 percent. I've also noticed that the battery percentage drops immediately after unplugging from the charger, it can be at 100 percent and within 15-20 minutes of non use it drops to 99 percent with another percentage drop in another 20 minutes but tends to hold steady around 96 percent. I've included some screen shots showing my battery usage.
It sounds like your getting great performance from your battery if your phone is off charge for 8-9 hours and you still have 70-60% leftover thats great
Ther can several things for example maybe try taking off "always on display"?
And also try going to the settings and hit the "optimize device" and maybe it will detect an app that is using to much background usage? Always make sure you are aslo not downloading apps that use too much memory as they can have back usage.