That looks like it will do the job too. I like that it’s automatic.Can't you find an automatic switch, such as this. https://www.amazon.com/dp/B00L9YVL90/?tag=caraudiocom-20
To add the tv, I got a second deep cycle battery, ran thick cable from my starter battery to the deep cycle battery(or you can run to a dc to dc charger then to deep cycle battery) I just use my alternator to charge the second battery, fused and added a disconnect switch between the two batteries. Then from the deep cycle battery connect an inverter that has enough watts to power the tv and ps5. Mine is 3500w but that’s quite a bit.Wait a TV in your van? Man I'm trying to put a TV in my jetta to play gta5 on ps5. How could I do this and stay connected to fiber optics?