Vehicle to Grid

[Zach3697]

I've had a thought about using my 14' Model S as a "power wall" in certain situations. I know Tesla doesn't support this but im thinking about this from a technical aspect. During DC fast charging, the battery is directly connected to the charge port so is it possible to make some communication board that gets the car to "start" a DC fast charging session and then instead of charging the battery, taking the ~400v from the charge port and feeding it into a home inverter?

Issues I see:
Firstly, since Tesla uses a proprietary communication protocol, is it know how to get the car to "DC Charge" without an actual supercharger? (I was thinking something Todo with the chademo adapter?)

Secondly, If the car detected current going the wrong way, would it instantly kill the session?

Not looking to implement but just an idea I thought might be cool to think about from a technical standpoint.

 

[jdwaverly]

A few people on Youtube have hooked up 2000 Watt inverters to the DC-DC converter in the car that normally charges the 12V battery. Everything worked, however, Tesla has now added "using the car as a power source" to their prohibited warranty terms. Yes, if you have the experience, you can directly tap into the HV system of the vehicle and then attach your own Inverter. Many solar energy systems connect panels in series to get HV that is fed to Inverter to produce 120V/240V.

A simpler approach(no HV) might be to use power from the car (12V) to charge an external battery bank that runs an inverter.
I have heard rumors that Tesla might provide an on board 120V inverter themselves. However, that would probably be <1000 watts to not overload existing wiring and power systems.

 

[NikolaTs]

A few people on Youtube have hooked up 2000 Watt inverters to the DC-DC converter in the car that normally charges the 12V battery. Everything worked, however, Tesla has now added "using the car as a power source" to their prohibited warranty terms. Yes, if you have the experience, you can directly tap into the HV system of the vehicle and then attach your own Inverter. Many solar energy systems connect panels in series to get HV that is fed to Inverter to produce 120V/240V.

A simpler approach(no HV) might be to use power from the car (12V) to charge an external battery bank that runs an inverter.
I have heard rumors that Tesla might provide an on board 120V inverter themselves. However, that would probably be <1000 watts to not overload existing wiring and power systems.

I know the high voltage is risky and not recommended, but can you simply plug a <1800 watt inverter into the cigarette lighter 12v, or would you need to wire it to the 12v battery directly? Will the HV battery keep the 12v charged automatically, or will the 12v be drained by doing this, and I would I need to force the car to stay awake with something like sentry mode?

I was recently looking into an inverter initially for powering 120v low draw items while camping, but I suppose there's nothing stopping me from using it as emergency backup, like you say charge up a emergency power bank like a bluetti BLUETTI , or even directly power a fridge with an extension cord, as long as it's less than 1,000 watts.

What got me thinking about this was this video of a V2L with an ioniq5

. There's nothing earth shattering going on here, he's just outputting 120v 15amp. We can do that with a simple 12v inverter I'd think, i personally wouldn't power the panel directly like this guy is, but I'd think you could at least run an extension cord to a few items in a pinch with a basic 12v inverter hooked up to the vehicle.

 

[ucmndd]

During DC fast charging, the battery is directly connected to the charge port

This is a very significant oversimplification. I'm sure there are numerous fault detection mechanisms that are very effective at preventing the car from sending current the wrong direction.

 

[leapingwhale]

I know the high voltage is risky and not recommended, but can you simply plug a <1800 watt inverter into the cigarette lighter 12v, or would you need to wire it to the 12v battery directly?

Don't do either. 1800 W / 12 V = 150 A.