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Discussion Starter #1
Hey everyone! Seen as everyone is in lock down / end of the world mode... I thought it might be interesting to investigate the possibility of bringing down the cost of V2X on Chademo.

Commercial solutions appear to start around £4k for something sensible, although the MiEV powerbox might be closer to £1500 if it actually exists in any supply chain!

Does anyone know of any projects to create a V2X (particularly off-grid backup scenario for power loss or camping) using arduino or raspberry pi units? I feel this should be possible. I've seen implementations to build chargers (but rarely documented and not in the reverse current direction) or the car side to receive current (see openinverter forums), but maybe I'm looking in the wrong places. There are enough solar PV systems that run similar battery voltages, should be possible I would think to use a solar inverter once the DC contactors are opened I would think.

Any thoughts?
 

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I think most DIY efforts have been out in to home batteries rather than V2X. if you're interested in that, i have links.

Problem with V2X as i understand it is
  • Pretty much only the Leaf supports it.
  • Only after a certain manufacture date i think
  • It's via the CHAdeMO port (?) So you get DC and need an offboard inverter.
So small selection of vehicles, expensive connector, funky protocols, and significant equipment cost.

AC Charging is a much simpler prospect, because it's a single specification, the cars have onboard charging circuits, and the communication is really simple.

That said, i could have garnered completely the wrong impression.
 

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Discussion Starter #3
I think most DIY efforts have been out in to home batteries rather than V2X. if you're interested in that, i have links.

Problem with V2X as i understand it is
  • Pretty much only the Leaf supports it.
  • Only after a certain manufacture date i think
  • It's via the CHAdeMO port (?) So you get DC and need an offboard inverter.
So small selection of vehicles, expensive connector, funky protocols, and significant equipment cost.

AC Charging is a much simpler prospect, because it's a single specification, the cars have onboard charging circuits, and the communication is really simple.

That said, i could have garnered completely the wrong impression.
What do you mean to home batteries? Export from car to home battery? I'm not looking for grid-tie per se. Might be relevant to what I'm looking for.

I think my Mitsubishi I-MiEV may support it, although it's unclear if it might require a firmware update or if that's only available to the Japanese market.

Your point is correct, only Chademo realistically has V2X support deployed... CCS is still trying to figure that out although I think they've published a standard possibly.

I'm not sure the relevance of AC charging to this question as you are talking about charging the car and I'm talking about exporting energy FROM the car that had previously been put into the car.
 

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I don't believe that there is a requirement for a firmware upgrade for the i-MiEV to use the Mitsubishi Power Box, but isn't that only for the Japanese market and 100 volts? Might also be the wrong frequency. They were about £1k new so might be a bit cheaper on the secondhand market although I suspect that Preppers will be hoarding them to use with their toilet paper. :rolleyes:
 

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What do you mean to home batteries? Export from car to home battery? I'm not looking for grid-tie per se. Might be relevant to what I'm looking for.
Standalone batteries in the home, like powerwalls. There's quite a lot of people designing and building diy versions of those.

I'm not sure the relevance of AC charging to this question as you are talking about charging the car and I'm talking about exporting energy FROM the car that had previously been put into the car.
You said you'd seen "projects to build chargers". I was saying that those projects are much simpler to do because so much of the equipment is already on the car, so it's not really comparable.

Also, i took a look at the schematics at openinverter.com. Be aware that's an inverter for an electric motor in a car. As such i expect it produces quite a dirty output wave at very variable frequencies. The controller takes accelerator and brake inputs. Probably not suitable for mains without a major redesign.

I'm currently trying to learn more about inverters, because I'm interested in doing a small battery with DIYBMS. I'm finding it hard to find ones that are suitable for grid mains connection.[/QUOTE]
 

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Discussion Starter #6
I don't believe that there is a requirement for a firmware upgrade for the i-MiEV to use the Mitsubishi Power Box, but isn't that only for the Japanese market and 100 volts? Might also be the wrong frequency. They were about £1k new so might be a bit cheaper on the secondhand market although I suspect that Preppers will be hoarding them to use with their toilet paper. :rolleyes:
Yes, PowerBox was only released in Japan, hence the difficulty in sourcing!

I've read the manual with the help of google translate and there is apparently a frequency switch 50/60 hz, but yes voltage is limited to 100v. Japan is dual frequency so this makes sense.
 

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Discussion Starter #7
Standalone batteries in the home, like powerwalls. There's quite a lot of people designing and building diy versions of those.



You said you'd seen "projects to build chargers". I was saying that those projects are much simpler to do because so much of the equipment is already on the car, so it's not really comparable.

Also, i took a look at the schematics at openinverter.com. Be aware that's an inverter for an electric motor in a car. As such i expect it produces quite a dirty output wave at very variable frequencies. The controller takes accelerator and brake inputs. Probably not suitable for mains without a major redesign.

I'm currently trying to learn more about inverters, because I'm interested in doing a small battery with DIYBMS. I'm finding it hard to find ones that are suitable for grid mains connection.
[/QUOTE]

ok I think we are talking about different things ;)

First, yes I'm quite aware of the DIY powerwall movement, and I think it's amazing! However, I'm not looking to invest in a large stationary battery pack at this time.

Secondly, you are correct, most of openinverter is related to creating opensource inverters to run motors and therefore convert cars to EV. Again, awesome project.

However, my reference to openinverter is actually to a fairly obsure piece of software for the charging infrastructure:


 

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Discussion Starter #8
They were about £1k new so might be a bit cheaper on the secondhand market although I suspect that Preppers will be hoarding them to use with their toilet paper. :rolleyes:
The main issue for me with the PowerBox, other than it being nearly nonexistent as a product, is the maximum capacity is so low, you'd barely be able to run a single induction burner off of it.

Google translation of specs from instruction PDF:

129097
 

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Hi all, if Japanese market device for Outlander and/or iMiev actually available, it could work with transformer to get back to lowish 220volts for UK off-grid usage. Or use 110v stuff. What do want to power? What kind of kVA.
 

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Discussion Starter #10
Hi all, if Japanese market device for Outlander and/or iMiev actually available, it could work with transformer to get back to lowish 220volts for UK off-grid usage. Or use 110v stuff. What do want to power? What kind of kVA.
This is exactly on point. I want to power all our computers, smart phones, do some cooking for meals, etc. So realistically the 1500w is actually probably enough as long as we don't cook WHILE running everything else as induction plates seem to be around 1500w at peak power usage.

The main issue is that I have only seen them listed on Rakuten and of course they are 'backordered' with no details as to if that means they exist or not. lol

So let's assume that we wanted to create a similar product, where to begin?
 

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Forget the induction hob and get a camping stove.

Lots of ways of powering computers and smart phones and all that low power stuff, eg solar cell, 12v battery and a nice pure sine inverter.
 

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Discussion Starter #12
Forget the induction hob and get a camping stove.

Lots of ways of powering computers and smart phones and all that low power stuff, eg solar cell, 12v battery and a nice pure sine inverter.
How does that work in a park where there is a legal injunction against using fire?
 

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Discussion Starter #14
Which park permits use of induction hobs?

Sandwiches and a thermos flask anyone?
I've yet to see a prohibition, but could be simply because no one has yet found a way to do it. ;)
 
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