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12V -> 230V, does the car battery charge the 12V battery or is it a traditional generator.

5746 Views 9 Replies 7 Participants Last post by  Roadblock
I'm a photographer and filmer.
In a petrol-based car I sometimes use the car with a 12VDC to 230VAC inverter and run the engine.
I think it's better emissions control than a portable generator.

How does the 12VDC system work in the ID.3?
Is the 12V battery continuously charged from the main car battery if the "engine is running?"

Or is it a traditional generator/alternator that charges the 12V battery while the car is on the move?
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There is a converter that takes power from the high voltage battery to charge/maintain the 12v battery; there is no generator.
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The 12V battery is charged as needed from the main car battery even if the "engine is not running". This was added in a recent update since the early ID.3 were having dead 12v batteries too often when just sitting parked, due to a low drain but always on portion of the electronics. You should be safe to run your inverter.
You can draw power from the 12V system while the HV system is powered on (car on).
I don't know what the power limit of the DC-DC converter is, but it could be a few kW in order to power the heater.

I have a 1500W inverter hooked up to the 12V battery on my Chevy Volt and it works fine on that car.
The 12V battery is charged as needed from the main car battery even if the "engine is not running". This was added in a recent update since the early ID.3 were having dead 12v batteries too often when just sitting parked, due to a low drain but always on portion of the electronics. You should be safe to run your inverter.
Perfect, then there isn’t any need for a mobil generator when working in the field.
The power from the fuel car 12V system worked fine.
The 12V battery is charged as needed from the main car battery even if the "engine is not running". This was added in a recent update since the early ID.3 were having dead 12v batteries too often when just sitting parked, due to a low drain but always on portion of the electronics. You should be safe to run your inverter.
... and it seem you can move a fuse to make the rear 12v outlet 'always on'. This would be great way to power a compressor refrigerator for car camping!

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... and it seem you can move a fuse to make the rear 12v outlet 'always on'. This would be great way to power a compressor refrigerator for car camping!

Has anybody successfully used a car refrigerator with their ID.4? With our Hyundai Santa Fe Hybrid our car refrigerator really sucks the voltage from the 12v battery to point of being unusable (even when driving). Luckily our Limited trim has the 120v inverter plug which we will use for the fridge.

Pretty sure the ID4 doesn't have a 120v plug (we have a '23 Pro Plus on order) so I'm a little concerned the 12v plug in the hatch might behave the same as our Santa Fe. Hopefully the converter is powerful enough to keep the 12v battery at high voltage when using a car fridge.

Our Tesla MY would run the car fridge just fine using the 12v hatch plug.
It works great with my fridge/freezer linked here. I don't leave it plugged in much when not driving, to avoid repeated cycling of the 12v which will harm it. It only draws 45 watts and can be set cold enough to keep frozen the entire 53 quarts of contents. It has a real compressor like in home fridges, which makes it much better than the more common and cheaper piezoelectric types.
It works great with my fridge/freezer linked here. I don't leave it plugged in much when not driving, to avoid repeated cycling of the 12v which will harm it. It only draws 45 watts and can be set cold enough to keep frozen the entire 53 quarts of contents. It has a real compressor like in home fridges, which makes it much better than the more common and cheaper piezoelectric types.
Thanks. Just realized this was an ID3 thread but I'm guessing the ID4 will be the same. We have a 26 quart fridge and a huge 100 quart model. Both use compressors like yours. I'm going to install a bluetooth battery module on the 12v battery of the ID4 so I can keep an eye on it. The 12v battery in our hybrid only charges when the car is at idle. So I have it set to power off after 30 minutes so the 12v can charge when my wife returns from work and I put it on a tender every weekend. I hope that is not necessary with the ID4. I have read the Hyundai Ioniq 5 has the same 12v problem as our hybrid. It's like the battery charge algorithm is for a lithium battery even though they are AGM batteries.
The 12V battery is charged as needed from the main car battery even if the "engine is not running". This was added in a recent update since the early ID.3 were having dead 12v batteries too often when just sitting parked, due to a low drain but always on portion of the electronics. You should be safe to run your inverter.
Not sure if it still needs to be plugged in. Namely, I have had some 12 V battery warnings and "charge by driving" notifications after the car has been parked overnight in cold without charging. There's also a power save mode that will kick in on too low 12 V and it will shut down 4G, Kessy etc. This has happened with SW 2.4. However, SW 3.0 seems to behave better.
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