Is it possible to run your car's system without the engine on using a charger?

I’ve been thinking about a setup where I could watch movies or listen to music in my car without needing the engine running. My car’s audio system is better than my house setup, and I have a nice big tablet I use for movies. I also have a battery charger, so I wonder if it’s possible to keep the system running without the engine. I know I can’t keep running the subwoofer for long before the battery dies, but would a charger be enough to keep everything working? It’s mainly for when I’m home alone. Right now, I can’t do it because my roommates would be mad if I had a subwoofer inside.

You could try using a trickle charger, leave it plugged in while you’re using it, and then use it until you need to drive. Something like this should work.

@Pax
I already have a 10 amp charger, but I’m not sure if it’ll keep the battery charged enough to run anything without it dying.

Jem said:
@Pax
I already have a 10 amp charger, but I’m not sure if it’ll keep the battery charged enough to run anything without it dying.

Are you trying to use your tablet while you’re in the car without turning the car on, but still keeping it in accessory mode?

Jem said:
@Pax
I already have a 10 amp charger, but I’m not sure if it’ll keep the battery charged enough to run anything without it dying.

That 10 amp charger is probably just a regular charger, not something meant to stay plugged in for a long time. Honestly, I don’t fully understand what you’re aiming for here.

@Pax
Yeah, like the other person said, I just want to watch movies or listen to music without starting the engine. The alternator isn’t running, so my battery usually dies quickly with the subs. I’m trying to figure out if there’s a charger that will keep the battery at 12 volts long enough to power everything without wasting gas or wearing down the engine.

@Jem
Well, if that’s the case, just use the charger you have and try it like that.

@Jem
I would highly recommend a deep cycle or lithium battery. A regular starting battery won’t last long in that situation and might be damaged over time.

You should just buy some good headphones, like Audio Technica or Denon. It’ll save you a lot of trouble.

Toryn said:
You should just buy some good headphones, like Audio Technica or Denon. It’ll save you a lot of trouble.

There’s nothing that beats the real feeling of bass. No headphones can give you that vibe.

Toryn said:
You should just buy some good headphones, like Audio Technica or Denon. It’ll save you a lot of trouble.

I already have a decent set of headphones, but they just can’t compete with the bass or highs from dedicated subs or big tweeters.

@Jem
You should try HiFiMan Sundara headphones. They give amazing sound quality and are well worth it.

Toryn said:
You should just buy some good headphones, like Audio Technica or Denon. It’ll save you a lot of trouble.

Headphones are good for personal listening, but an audio system is for the full body experience.

This will work for sure. I’d suggest adding a voltage readout in your dash so you can monitor when to reduce the power if the charger isn’t keeping up. I’ve used a car 12v system for a house setup before, just add another battery and charger. You could even go for more powerful 12v chargers if needed. A regular 120v 15a wall socket can supply up to 100a for a 12v charger.

@Farley
That’s a great idea! I already have a voltage reader, since my stock electrical system can barely handle my RP 1500.

I think it’s possible, but I’d suggest limiting it to a couple of hours at a time just to play it safe.

Check out “converter chargers” on Amazon. They’re made for RVs and can go up to 100 amps, perfect for when you’re plugged into shore power.

Mika said:
Check out “converter chargers” on Amazon. They’re made for RVs and can go up to 100 amps, perfect for when you’re plugged into shore power.

A 100 amp charger would be perfect. It’s close to my 130 amp alternator, so I think it should work as long as I’m not blasting the subs at full volume.

@Jem
Here’s one to check out: PowerMax PM3-100LK 110V to 12V DC Power Supply Converter Charger for RV 100 Amp - Amazon.com: PowerMax PM3-100LK 110V to 12V DV Power Supply Converter Charger for RV 100 Amp -Grade Voltage Converter Modified SINE Wave Inverter : Electronics

What kind of battery are you using? You should try an AGM deep cycle battery with good capacity, and keep an eye on the voltage. If it hits around 11V, start the car to avoid needing a jump start.