Using a Volt as a emergency battery

baskinginthesun2000

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I got the idea that a Chevy Volt might work as an emergency battery for a hybrid inverter. Have a huawei's sun2000 usl0 inverter, which uses the high voltage LG Resu battery (400V). From what I've been able to find, the Volt's battery also runs around that range. If the car has the dc charging option, the battery seems to connect directly to the charging port (though a contactor). So my guess is you should be able to use the car's battery as a backup for the inverter.

On the inverter, the battery port seems to be connected in parallel to the PV panels, and the highest voltage I've seen after almost a year is 450V, and the mode is 365V. If the inverter detects the battery, it will limit the voltage (think 390V?? don't recall the value), so it seems that the inverter should be able to draw from the car. For charging you would use the ac connection since you probably would gain little (10kW vs 7.2kW? ) for the extra complication of providing a dc-dc converter and charge limiter.

Batteries for my current set up are a bit expensive and don't need them to balance the load throughout the day. I'm interested in emergency use, and our area has experienced outages for a few days occasionally. The car battery should provide a few day's worths of energy, and during daylight hours should recharge
 
Where would you get the Chevy volt battery.
 
I think the OP is referring to a whole Volt. not just a battery.
later floyd
 
Yeah thats what I assumed he meant. I use 3 of the modules from a full pack
 
floydR said:
I think the OP is referring to a whole Volt. not just a battery.
later floyd
Yes, I meant plug in the car to the inverter using the charging port. If you want to be fancy, you could have the plug that goes into the car carry both dc and ac, and a box with a few contactors to switch terminals. DC to the inverter, if the power is out, and AC if available). The idea isn't something that powers the house all the time, only when there isn't any AC on the grid.

Usually, the backup ability of the inverter doesn't kick in (night), but a few times it has worked during the day. However, one time it kept trying to power the house and it was too much of a load so it kept tripping off.

Today we didn't have an outage but had there been a few times it would have been nice there was a battery to provide enough energy for the loads. If the yellow line (load) shows, there should had been enough power from the panels (green line)

image_rccsvb.jpg
 
Got ya, you meant the entire car
 
baskinginthesun2000 said:
floydR said:
I think the OP is referring to a whole Volt. not just a battery.
later floyd
Yes, I meant plug in the car to the inverter using the charging port. If you want to be fancy, you could have the plug that goes into the car carry both dc and ac, and a box with a few contactors to switch terminals. DC to the inverter, if the power is out, and AC if available). The idea isn't something that powers the house all the time, only when there isn't any AC on the grid.

Unfortunately, the charging port isn't going to work with a Volt. The Volt has a J1772 charging port, which is AC only, that connects to the onboard charger in the vehicle. There is no direct access to the high voltage battery through that port.

ga2500ev
 
ga2500ev said:
baskinginthesun2000 said:
floydR said:
I think the OP is referring to a whole Volt. not just a battery.
later floyd
Yes, I meant plug in the car to the inverter using the charging port. If you want to be fancy, you could have the plug that goes into the car carry both dc and ac, and a box with a few contactors to switch terminals. DC to the inverter, if the power is out, and AC if available). The idea isn't something that powers the house all the time, only when there isn't any AC on the grid.

Unfortunately, the charging port isn't going to work with a Volt. The Volt has a J1772 charging port, which is AC only, that connects to the onboard charger in the vehicle. There is no direct access to the high voltage battery through that port.

ga2500ev
Probably have the names confused (Volt or Bolt, whoever chose those? :-/ ). Anyway, the correct car as a DC Fast Charging port, and from what I understand, it is connected to the battery bus. The battery is around 400V and think chevy is thinking of using the basic design in several of their other electric cars. So the concept might work with other models in the future.
 
The Bolt has CCS quick charging, which is putting DC current directly from the charger into the battery. However, that way of charging is still controlled by the car's BMS. CCS currently does not allow 2 way current transfer, meaning you can only charge, not discharge. This is maybe coming in the future, but it certainly isn't built into the Bolt right now. I suspect that the BMS will disconnect the battery when you try to discharge.

Cars with ChaDeMo ports are known to be able to be discharged because it is a feature of the ChaDeMo standard. So you'd be looking at a Nissan Leaf or something like that.
 
There's a youtube where the guy dropped hisNissan Leaf battery pack - figured out the wiring - and added (in parallel) a battery he built for the back. [size=small][size=small]Here's the 2nd youtube in the Nissan Leaf battery extenderseries -[/size][/size][size=small][size=small]
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Ultimately these battery packshave+ and - wires and a voltage and it might be possible to tap in but yet leave the car's BMS etc active. The youtube above shows that its not impossible.I wonder if you could 'figure out' some connection points of the battery - and run a custom plug.

Take the output of the battery pack and find amatching charge controller (that accepts 400-500dcv input)? And then use that to power abattery/inverter system for home consumption?

P.S. This is random thinking on my part - I have no experience in this and not pushing it... !
 
I'd think very hard before doing such modifications. Wouldn't be surprised if the BMS interpreted the surprise drop in voltage as a potentially catastrophic damage to the battery, and refused all further operations. And GMC technicians could rightly refuse to even look at such modified high voltage stuff.
 
idur said:
The Bolt has CCS quick charging, which is putting DC current directly from the charger into the battery. However, that way of charging is still controlled by the car's BMS. CCS currently does not allow 2 way current transfer, meaning you can only charge, not discharge. This is maybe coming in the future, but it certainly isn't built into the Bolt right now. I suspect that the BMS will disconnect the battery when you try to discharge.

Cars with ChaDeMo ports are known to be able to be discharged because it is a feature of the ChaDeMo standard. So you'd be looking at a Nissan Leaf or something like that.

Thanks. I had seen the contactor, but didn't consider that the bms would disconnect it if power was being drawn. The Volt looked just perfect for this use. hmm


ajw22 said:
I'd think very hard before doing such modifications. Wouldn't be surprised if the BMS interpreted the surprise drop in voltage as a potentially catastrophic damage to the battery, and refused all further operations. And GMC technicians could rightly refuse to even look at such modified high voltage stuff.

It wouldn't require any modifications. If it worked, the inverter would be connected via the charge port to the battery bus. Seems only a contactor lies between. The voltage shouldn't drop that dramatically, though after a while there should be some because of the power drawn. Think the bms controller is active all the time.

However, as Idur said the software side might do all sorts of crazy.
 
On top of the BMS issues, you may struggle to find an inverter that works in the 400v range.

I have used my Bolt as a backup power source. But, I used a 12v inverter. Sure it's less efficient to have the car convert from 400vdc to 14vdc then convert from 14vdc to AC, but it also didn't require modifying the car.
 
I've heard about 12V inverters too. With a LEAF you could use a 1kW inverter since that is the power for the DC-DC converter in the car.
You also have to keep a LEAF in the ready-to-drive mode so it keeps charging the 12V battery.
I don't know what the requirements are for something like that on the Bolt.

Depending on the emergency, it could work.
 
Thanks. I'm rather set on using an EV as a battery for the inverter at 400V. Not sure if the bolt won't, since the opinion is that it might not. There is a company that states that it can. https://dcbel.ossiaco.com/

Don't need the car to line inverter they make, but still seems that the idea might be doable
 
The company has a nice website. On the Our technology page, there is a link to a FAQ.

I'll quote from that document:
https://www.ossiaco.com/wp-content/uploads/2020/06/dcbel-by-Ossiaco-FAQ-v1.1.pdf said:
What EVs are compatible with Blackout Power?
Blackout Power is the beloved dcbel feature that uses the energy stored in your EVs massive battery to power your home in a utility grid blackout. This is otherwise known as bidrectional charging, two-way power flow, V2H (vehicle-to-home) or power discharge.
Compatibility with dcbels Blackout Power feature requires a multi-part response:
1. Does the technical standard that the EV is built to allow for bidrectional power flow and communication?
There are two major global DC EV charging standards: CHAdeMO and CCS. All EVs built to the CHAdeMO standard like the Nissan Leaf and Mitsubishi Outlander are currently compatible with Blackout Power while, as a rule of thumb, pre-2021 CCS vehicles like the Chevrolet Bolt are not currently supported. The CCS standards are currently being revised to allow EVs built to CCS standards to support bidrectional power flows. The revised standards are scheduled to be published this year (2020) and dcbel was designed to be ready for the CCS protocol update and will be able to support Blackout Power via CCS with a small over the air upgrade shortly after the updated protocol is published.

So they say they'll update their equipment when the standards for CCS get rewritten. They don't say anything about when CCS equipped cars like the Bolt will support two way charging.

Like I said, it may come to the Bolt in the future.

Edit: good find though, I am on the lookout for such equipment to use with my LEAF, but it isn't widely commercially available.
 
idur said:
So they say they'll update their equipment when the standards for CCS get rewritten. They don't say anything about when CCS equipped cars like the Bolt will support two way charging.

Like I said, it may come to the Bolt in the future.

Edit: good find though, I am on the lookout for such equipment to use with my LEAF, but it isn't widely commercially available.
Thanks :(

So I guess I will need to wait a bit more. Hopefully, by then ev will be cheaper, and doing this will be easier. The bolt just sounded like nice car from the engineering point of view. I'm surprised gm did such a good job with it.

Usually don't accept negatives at face value, since things aren't always as black or white as they say. '21 are coming out soon, so will keep my fingers crossed


as a rule of thumb,pre-2021 CCS vehicleslike the Chevrolet Boltare notcurrently supported

However, seems my idea is right on the money. They basically are doing the same

What stationary batteries is dcbelcompatible with?dcbelis compatible with all batteriesthat have a 400V DC nominal voltagelike the LG Chem RESU



Good luck getting one for your leaf.
 
baskinginthesun2000 said:
So I guess I will need to wait a bit more. Hopefully, by then ev will be cheaper, and doing this will be easier. The bolt just sounded like nice car from the engineering point of view. I'm surprised gm did such a good job with it.

Yes, the Bolt is a marvel of engineering. I hope GM enables two way charging on it as soon as feasable.

Maybe even retrofit it to older model years for a fee. It should only be a BMS software update.
 
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