Whats the real skinny on V2H or V2L with a Leaf?

My Nissan Leaf Forum

Help Support My Nissan Leaf Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

connellbsd

Member
Joined
Dec 18, 2010
Messages
10
Location
San Diego
I read a few posts below that made me think its being done, but possibly badly. My Cuz is buying a new battery from someone here in San Diego (San Marcos) that will give him ~200+ miles range on his ~2016 Leaf with Chadmo. I'm curious what the options are for powering his house during blackouts? -Bill
 
In terms of powering things from a Leaf's DC CHAdeMO connector, you used to be able to buy Setec V2L 3kW and 6kW units from www.evsiphon.com, but no longer. There is still information about V2H more broadly on that site, however. (And there might still be alternative sources for the Setec units.)

However, just in general you can connect a "12V" inverter to a Leaf just as you could to an ICE car; even better, since there won't be any exhaust emissions to deal with. (You can run it in a garage with the door closed!)

Perhaps connecting under the hood to the 12V system is what you mean by "being done, but possibly badly", but I think "badly" is overstating it. The biggest limitation is that you can only go so far in inverter wattage before exceeding the current budget for the Leaf's 12V charger. You won't be getting 3kW+ that way.

If by badly you just mean "home-brew" in the sense of cables everywhere and the solution not being "tidy", there's some assistance for that.

First, if you don't like using jumper-style cables to connect to the Leaf, there are cleaner wiring kits available here:

www.evextend.com

Second, if you'd like the inverter itself to be more packaged (and ideally weatherproof), there's this source:

www.cargenerator.com

cargenerator_photo001.jpg
 
I read a few posts below that made me think its being done, but possibly badly. My Cuz is buying a new battery from someone here in San Diego (San Marcos) that will give him ~200+ miles range on his ~2016 Leaf with Chadmo. I'm curious what the options are for powering his house during blackouts? -Bill
You have two options. One is using the ChaDeMo port which is how it was intended to draw power from the Leaf to power something. The other is to tap the 12V system with an inverter, but this has a limit of roughly 1,500 watts. About the same as having one working 120V outlet in your home. Both can be done in a safe manner when wired correctly and setup for the proper power loads. I've been using the 12V tap method for nearly a decade now because it was the cheapest setup for me, though limited as it is, still plenty of power for a blackout if you need to keep food cold, run a microwave to cook food, lights, TV, etc.
 
I'm assuming the "big" battery tops up the small 12v battery so inessence you are connecting to the "big" battery through some sort of 12 battery charger on the leaf. Does this mean you have to leave the car switched on ? or will this work with the car switched off and locked ? On the old ICE cars leaving the ignition on for too long cause damage like burnt out ignition coils etc. If you have to leave the leaf on to be able to extract from it in this way is there any risk of damage to the car ? It does seem the simplest way to get a 1kw out out of it at a push..
 
I'm assuming the "big" battery tops up the small 12v battery so inessence you are connecting to the "big" battery through some sort of 12 battery charger on the leaf. Does this mean you have to leave the car switched on ? or will this work with the car switched off and locked ? On the old ICE cars leaving the ignition on for too long cause damage like burnt out ignition coils etc. If you have to leave the leaf on to be able to extract from it in this way is there any risk of damage to the car ? It does seem the simplest way to get a 1kw out out of it at a push..

How would you use the ChaDeMo ?
 
I'm assuming the "big" battery tops up the small 12v battery so inessence you are connecting to the "big" battery through some sort of 12 battery charger on the leaf. Does this mean you have to leave the car switched on ? or will this work with the car switched off and locked ? On the old ICE cars leaving the ignition on for too long cause damage like burnt out ignition coils etc. If you have to leave the leaf on to be able to extract from it in this way is there any risk of damage to the car ? It does seem the simplest way to get a 1kw out out of it at a push..
Yes, both methods use the "big" battery, just one is officially supported (via ChaDeMo) and the other is a hacky way of accessing the power. 😄

Yes, via ChaDeMo, you don't need a key. When using the 12V system, you have to leave the Leaf in "drive" mode. You can still turn off everything (lights, AC, fans, radio, etc.) and lock the Leaf doing this. I've done it for literal days at a time during emergencies. I can't speak for all models, but my 2013 and 2020 have been "on" for days at a time with no ill effect for almost a dozens times in their lifetime of use.

Using the 12V for power does take some electrical science knowledge though or else bad things could happen if you try to draw too much power, wire it wrong, size the power wrong, etc.

Any of the old assumptions about ICE vehicles have to be left behind when dealing with an EV as it's a completely different beast in its own right. 😯

The only thing I will add is that the method of taping the 12V power does use the DC to DC buck converter, which produces a little heat. That just means to make sure your coolant system is filled properly and that you have no water pump issues, which is a rare thing, but it does happen from the post others have made here. Basically, if your Leaf is not producing dash codes about the water pumps or coolant already, then you should be fine.
 
Yes, both methods use the "big" battery, just one is officially supported (via ChaDeMo) and the other is a hacky way of accessing the power. 😄

Yes, via ChaDeMo, you don't need a key. When using the 12V system, you have to leave the Leaf in "drive" mode. You can still turn off everything (lights, AC, fans, radio, etc.) and lock the Leaf doing this. I've done it for literal days at a time during emergencies. I can't speak for all models, but my 2013 and 2020 have been "on" for days at a time with no ill effect for almost a dozens times in their lifetime of use.

Using the 12V for power does take some electrical science knowledge though or else bad things could happen if you try to draw too much power, wire it wrong, size the power wrong, etc.

Any of the old assumptions about ICE vehicles have to be left behind when dealing with an EV as it's a completely different beast in its own right. 😯

The only thing I will add is that the method of taping the 12V power does use the DC to DC buck converter, which produces a little heat. That just means to make sure your coolant system is filled properly and that you have no water pump issues, which is a rare thing, but it does happen from the post others have made here. Basically, if your Leaf is not producing dash codes about the water pumps or coolant already, then you should be fine.
I'm also trying to use the V2L option via
 
Getting a Chademo connector is a big part of the problem and they are expen$ive if you can even find one.

In the early model cars the main contactors for the DCQC are located in the HVJB near the front firewall, and in the later cars they are in the PDM with their own little driver board. If you can engage the contactors then HV will be present on the terminals of the Chademo charge port.

chademo board.jpeg
 
I'm in the UK but it doesn't look like an off the shelf Chademo option is available here either.
If I'm reading the above post correctly it is a simple contactor that connects the terminals of the battery to the chademo pins ? No solid state stuff ? I guess it also goes through various protection electronics. My car is a 2023 model so I'm a little reluctant to be connecting to control boards just yet..
 
I'm in the UK but it doesn't look like an off the shelf Chademo option is available here either.
If I'm reading the above post correctly it is a simple contactor that connects the terminals of the battery to the chademo pins ? No solid state stuff ? I guess it also goes through various protection electronics. My car is a 2023 model so I'm a little reluctant to be connecting to control boards just yet..
Plus the contactor in the battery, which has a precharge relay as well. Sure you could hack the controllers to get DC at the Chademo port, but you have no way of protecting the battery from over discharge. To get power safely from the main battery, you need the battery's BMS in the control loop. So, an actual Chademo V2X device, or grab 12 volt at the accessory battery.

If I seriously wanted to get 350 VDC power from the main battery, I would put the car into ON, but not READY TO DRIVE, then get DC from somewhere between the battery and the PDM. This way, if the car decides to shut down to protect the battery, the DC would just stop. One place to get the 350 VDC is inside the PDM if there is room. Must implement with real fuses and other safety features. The Chademo connector is overkill for just getting 5 or 10 kw out of the main battery. It would be neat for someone to test this. Pull 5 or 10 amps at 350 VDC for an hour or two and see if the car gets any DTCs. This would also be any easy kit to design and sell. Now, where do we find cheap 400 VDC inverters...
 
Last edited:
Assumedly any normal charger has this BMS data. Is one of the pins in the chademo plug a comms port ? The EV charger must communicate to the BMS and get the SOC levels etc and tell it to close the contactors. Would it be possible to sniff these communications and just replicate them with an arduino ?
Yes good point about a 400v inverter I don't suppose they are very available or cheap... Switching it on and off just from the Chademo plug seems a neat thing to do rather than wire in to the battery circuit direct..
 
Just though I already have a max 500vdc input inverter wired up to the house. One of my solar PV inverters only have one string of PV's attached to it and thus I have other ports that would take the 350v chademo.. Probably most solar Pv inverters would do this job and are probably the cheapest option..
 
I'm assuming the "big" battery tops up the small 12v battery so inessence you are connecting to the "big" battery through some sort of 12 battery charger on the leaf. Does this mean you have to leave the car switched on ? or will this work with the car switched off and locked ? On the old ICE cars leaving the ignition on for too long cause damage like burnt out ignition coils etc. If you have to leave the leaf on to be able to extract from it in this way is there any risk of damage to the car ? It does seem the simplest way to get a 1kw out out of it at a push..
Yes. Car needs to be powered ‘On’. No need to worry about burning out the ignition — none of that equipment exists. You are correct this is the simplest way to get about 1 kw power out of the car. I ran two heavy-duty extension cords off a 1.5 kw inverter (connected to the 12v battery) for about two days — it easily ran two refrigerators, one k-cup coffee maker, one cable internet connection, and quite a number of lights and power strips to charge cell phones and iPads. I estimate this setup is good for about 10 days to two weeks.
 
Back
Top