Though not designed for deep-cycle applications without the car's engine running, a typical 600 watt-hour car starting battery should be able to power a portable DC 1.5-amp TV/DVD player for about 16 hours or a 32" LED TV (30-watts) for about 7.5 hours and still be able to start the car's engine.
Table with Amp Hours (AH) based on your car's RC or CCA number: [ Ссылка ]
"Kill a Watt" meter to check your TV's power usage: [ Ссылка ]
