Also, inverters use a lot more energy than 12v appliances do, so you will get way less TV watching time out of a 110v TV plugged into an inverter than you will out of a 12v TV running right off of your battery. There are lots of 12v TV's out there. A lot of TV's these days actually run off of 12v but have a 110v to 12v transformer, so you are double-converting your voltages if you are plugging into an inverter.
My friend is an electrical engineer and one time he saw that I had a 110v USB outlet plugged into our inverter and he educated me. He gave me some 12V USB outlets next time I saw him.