Charging up your solar batteries from V2L in your car - Is it possible?

DownByTheGarden · 27-01-2023 04:03PM #1

I have a question about charging up your solar batteries from V2L in your car - Is it possible?

If it is how hard is it to set up. Would the cost of it outweigh the convenience.

Im thinking for the odd day when they battery starts to run out to give it a boost from the car for the night.

SD_DRACULA · 27-01-2023 06:10PM

Cheapest charger that can do that is around 5k so yeah, not worth it at this time.

https://wallbox.com/en_ie/quasar-dc-charger

There may be more starting to come out but only aware of that one.

Jonathan · 27-01-2023 06:32PM

https://www.boards.ie/discussion/comment/120166770#Comment_120166770

The MG4 has a fully bidirectional 7kW OBC. 😉

No wallbox/chademo required, just a type 2 cable. Only V2L though, not V2G, so easiest thing would be to connect a rectifier to the PV batteries as the V2L load.

https://www.mgevs.com/threads/v2l-test-7kw-output.8427/page-3#post-139791

graememk · 27-01-2023 06:40PM

https://www.boards.ie/discussion/2058281632/charging-up-your-solar-batteries-from-v2l-in-your-car-is-it-possible

Yes, if you use a 58v charger, takes 3kw ac and outputs DC.

DC999 · 27-01-2023 07:13PM

https://www.boards.ie/discussion/comment/120166873#Comment_120166873

Wow, never even knew they did EVs. That could be our next one when our Leaf is moving on :) 50kWh battery for 27k. MG4 Electric Hatchback | MG Motor Ireland.

Sustained 7kW is a higher output than any of the house batteries we see on Boards. Ok, worth considering & debating the impact on the car battery in the longer term. But V2L would deffo help once we all get into costly TOU tariffs at peak times.

unkel · 27-01-2023 09:56PM

@SD_DRACULA - "Cheapest charger that can do that is around 5k so yeah, not worth it at this time."

Not at all. This 3kW €55 lad will do the job. I have one myself.

https://www.aliexpress.com/item/1005003755306962.html?spm=a2g0o.order_list.order_list_main.50.2a351802YkzkV3

Presuming of course you have a 48V nominal battery like most of us do. You can get that rectifier in different voltages, mine is 58V, perfect for 16S LiFePO4

SD_DRACULA · 27-01-2023 10:34PM

Yeah I was talking about a bi-directional charger type for V2H/V2G, the proper job.

But yeah sure V2L is just a plug from the batteries so that will do the trick.

unkel · 27-01-2023 10:40PM

https://www.boards.ie/discussion/comment/120168091#Comment_120168091

Not what he asked ;-)

Although I am with you that the next best thing since sliced bread is proper smart bi-directional AC charging and discharging between car and chargepoint for proper V2G

Or !!! skipping the wait for OEMs to install bi-directional AC charging and to just do it with DC (CHAdeMO or CCS). Friend of mine is working on commercialising an affordable (sub €1k) solution for this. Now that is something that is interesting as it would work for all EVs, no matter what AC charging you have or how old your EV is.

DownByTheGarden · 01-02-2023 08:09AM

So can you get a cable that i can run from the battery that i can just plug into the V2L socket in the car?

eg just plug the house battery in to charge it from the car?

unkel · 01-02-2023 09:45AM

https://www.boards.ie/discussion/comment/120185638#Comment_120185638

Not a cable. Did you read my post? The rectifier I linked to will do the job. Or any other AC device that can charge up your battery. Not sure if I would recommend doing that, you haven't even mentioned what battery you have, you seem to be unfamiliar with this stuff, no offence! Presumably it's not a DIY 48V battery you have.

SD_DRACULA · 01-02-2023 09:53AM

https://www.boards.ie/discussion/comment/120168118#Comment_120168118

I only read up about a pilot they are running in the UK for this exact scenario a few days back, can't recall the link.

But how can you get current out from the car if it only allows current in?

unkel · 01-02-2023 09:58AM

https://www.boards.ie/discussion/comment/120186050#Comment_120186050

They've been doing it in Japan since 2011 (after the nuclear disaster). CHAdeMO works bi-directional by design. So high voltage DC out and high voltage DC in.

You can buy a portable CHAdeMO DC (bi-directional) charger for home use off the shelf. Not cheap though, last time I looked they were close to $3k, plus shipping and taxes, etc.

DownByTheGarden · 01-02-2023 10:01AM

https://www.boards.ie/discussion/comment/120186016#Comment_120186016

Sorry, my bad, I am indeed unfamiliar with it. Thought it was in a different language :)

I was looking for something as close to plug and play as possible. Have 2x 5kwh puredrive batteries.

What connects to what and how?

I assume that rectifier sits beside the inverter, somehow wired to the inverter? And then the other end plugs into the car?

SD_DRACULA · 01-02-2023 10:16AM

https://www.boards.ie/discussion/comment/120186076#Comment_120186076

Only interested in CCS 😁

DC999 · 01-02-2023 10:54AM

https://www.boards.ie/discussion/comment/120186076#Comment_120186076

https://www.boards.ie/discussion/comment/120186050#Comment_120186050

Yeah, UK V2H trial is Vehicle To Home (V2H) Bidirectional Chargers | INDRA. So Leaf has that and they are going with them first afaik. Looked good if got selected, they provided the kit or was a small charge. Wasn’t fully clear how it worked or costs – application for the trial was vague. But I would have tried it had it been available here. As it's V2H, you'd control it so wouldn't hammer the battery like a V2G could.

SD_DRACULA · 01-02-2023 10:56AM

This was the article: https://thedriven.io/2023/01/23/world-first-trial-with-ccs-could-open-up-vehicle-to-everything-technology-to-all-evs/

But unclear if the cars must have bi-directional charging already enabled, sort of pointless if so as not many do.

graememk · 01-02-2023 10:56AM

https://www.boards.ie/discussion/comment/120186086#Comment_120186086

The charger linked , connects directly to the battery. Then you power the charger from the car.

To connect it in the battery would need to be disconnected from the inverter, possibly some sort of bus bar installed so you can connect everything,

When you power the charger, it will just push out the 58v until it's turned off. It won't overcharge the batteries though as the batteries reach capacity their voltage will rise current will slow to a trickle and/or the bms will cut off the charge.

It's doable, but you need to have a good understanding of how everything works

unkel · 01-02-2023 01:58PM

https://www.boards.ie/discussion/comment/120186350#Comment_120186350

Not unclear. All CHAdeMO cars have bi-directional DC charging by definition. That's why that trial was limited to CHAdeMO cars. That crowd in the UK made it sound like they were doing something revolutionary (and people seemed to believe them), but this was done in Japan 12 years ago. Which is a very long time ago in the history of modern EVs 😂

Charging up your solar batteries from V2L in your car - Is it possible?

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