Using Nissan Leaf battery as home power storage

Himselfe

I have a Nissan Leaf on which I'm replacing the battery and intend to use the old battery as a 'power wall'. I'm told that only a Fronius invertor can make this possible. I know its niche but I'd love to be able to keep the battery in use as it has at least 20kw left in it for use which would be perfect for running a home.

I also intend on installing solar panels to power the house and battery. I have someone who can hook up the battery to the Fronius (and has plenty of experience doing this) however I can't find a solar installer who will do the panels and the Fronius for me, they all want to stick to their own preferred brands.

Has anyone any experience of this or advice to offer?

SharkMX

https://www.boards.ie/discussion/2058327431/using-nissan-leaf-battery-as-home-power-storage

My old man has been trying for ages to do this and no luck. Everyone says it can be done, but noone seems to know how to get it done.

If you had the car you can get a wall box V2G (that costs a fortune) that can take the battery power into the house.

graememk

Of course there is ways and I do have a few ideas. But most of the time it's not worth it unfortunately.

The pack is made up of "cells" and it has a voltage range of 8.4v - 5.6v

7 of them in series would make a 58.8v max charge pack but there isn't any BMS in play here either to talk to the inverter.

It's also lithium ion (not to be confused with lithium IRON, or LFP) lithium ion are much more dangerous Vs the LFP batteries. (Gel have a great video comparing the different types and how they react to puncture and fire)

If your replacing the battery, it must be pretty degraded (say half) and your only really left with a 12kWh battery.

You can buy 16 new LFP cells, for just over 1k now and that's 15kWh of a safer chemistry. 1-200 for a BMS and your done. If you really want to push the boat out you can get a case and BMS for £500

It's unfortunately not worth the effort for home storage.

If you can sell the old battery you'd be better off doing that and buying new cells.- and much less space.

Himselfe

Thanks for the quick responses. Its a lot to consider. I'm edging towards just selling the battery at this point but I'll see what this chap who says he can install it with a fronius says before I make a decision and report back here for anyone interested.

AmpMan

@graememk Have you a link to those cells?Thanks

graememk

https://www.boards.ie/discussion/comment/121513714#Comment_121513714

It's the ones from nkon.nl don't have it handy

slave1

https://www.boards.ie/discussion/comment/121513714#Comment_121513714

for example....

Envision ESS 4LH3L7 280Ah - LiFePO4 - 3.2V B - grade - Prismatic - LiFePO4 - Rechargeable batteries | NKON

DC999

https://www.boards.ie/discussion/2058327431/using-nissan-leaf-battery-as-home-power-storage

I've an old Leaf. To upgrade the car, what sort of cost are you looking at and what size battery will you get in it for that?

Himselfe

https://www.boards.ie/discussion/comment/121514880#Comment_121514880

There's a place up north that specialise in electric car salvage and they provide a first dibs arrangement to a crowd down south called Range Therapy who do the swap out for a cost. They have a long waiting list. The swap out is one service they offer but they also offer additional capacity with new (non leaf) batteries that fit in the boot (I think?) and just increase your range on top of what you already have.

It can be difficult to come by a decent second hand battery for a full swap out like I am doing. The battery I've gotten cost in the region of €7,000. I'm upgrading my high spec 30Kw 2016 model that has only about 50% range left on it (over 160,000 km) to a 40Kwh battery with only 5000 kms on it. My Leaf is in perfect condition apart from the battery and this upgrade should hopefully give me plenty more years happy driving for what I consider a very reasonable cost.

As far as I know any leaf can be swapped to a higher capacity battery with one exception where the 24Kwh versions can only go up to 40Kwh. Every other version can be swapped out for a 60Kwh, but they are a very rare find.

unkel

https://www.boards.ie/discussion/comment/121515187#Comment_121515187

It is beyond me why Range Therapy have any waiting lists. Basically if you are letting them upgrade your battery, you are destroying your money. And there are insurance implications, you are obliged to tell your insurer about this modification. Although they seem to deny this.

If the range of your car is no longer sufficient, it makes a lot more economic sense to just sell your EV and buy another one with more range. As in sell your Leaf with 50km range for €3k and buy an Ioniq with 200km range for €10k. If you spend the same €7k to upgrade your Leaf, you end up with a vehicle worth maybe €5k, so you will have lost / depreciated €5k instantly

Himselfe

https://www.boards.ie/discussion/comment/121541305#Comment_121541305

I am not upgrading the battery. I am replacing it with another one which will give me a circa 200km range. You are basically suggesting that I spend €3k more to get the same result.

unkel

https://www.boards.ie/discussion/comment/121561752#Comment_121561752

How am I suggesting that? Basically your car is worth about €3k. You could sell it, add €7k of your own money and buy a €10k Ioniq

Or keep it and spend the same €7k of your own money on the battery upgrade with Range Therapy

And the result is very different. With Range Therapy, your Leaf with the new battery might be worth about €5-6k. The Ioniq will still be worth €10k. So Range Therapy instantly wastes €4-5k of your own money. Each to their own, you can do with your hard earned as you please. But a complete waste of money it is.

unkel

Apologies, I presumed you had an early 2011/2012 24kWh Leaf. I see now that you have a 2016 30kWh Leaf (with half the range left), so your car is worth a good bit more than €3k. But the core of my argument stands.

Himselfe

https://www.boards.ie/discussion/comment/121561828#Comment_121561828

Yes, I think it makes sense for me to replace the battery in my 2016 Leaf, in fact it will have a longer range than it had when I bought it originally. If I get another 8 years out of it I'll be delighted.

It's not all about depreciation for me. I have a car that I enjoy driving, is cheap as chips to run, has minimal maintenance costs and is in perfect working order, apart from the battery which is easily replaced. I don't see the point of letting it go to the scrap heap which is likely where it would end up sooner than later if I sell it and someone else doesn't decide to replace the battery like I have.

I'm not sure I would agree with your analysis on the 2011/2012 numbers though. Spending €7k to replace a 2011/2012 24kWh Leaf battery (assuming the car has no mechanical issues) with a 40kWh battery to achieve 200km range is still €3k cheaper than spending €10k on an Ioniq with the same range. Range is, as we all know, one of the biggest deciding factors for most when it comes to EVs. If I can get the same for €3k less I know where I will be spending my money.

I take your point on the potential for depreciation on an older car, but as I said, there are other factors to consider and it would be interesting to see if a Leaf from that far back with a battery replacement giving it 200km of range would sell for more than the €5k the 2 on Carzone today are going for (with presumably 50-60 km range).

unkel

@Himselfe - "Spending €7k to replace a 2011/2012 24kWh Leaf battery (assuming the car has no mechanical issues) with a 40kWh battery to achieve 200km range is still €3k cheaper than spending €10k on an Ioniq with the same range. "

It's not though as you could sell the current car for €3k in my example. Outlay in both cases is a net €7k 😂

Himselfe

https://www.boards.ie/discussion/comment/121562226#Comment_121562226

Putting time and effort into selling a car is also a considerable outlay, in this case for zero additional benefit.

slave1

I would not have an Ioniq, prefer the uber comfy seats of the Leaf and remote App for preheating

Himselfe

https://www.boards.ie/discussion/comment/121562392#Comment_121562392

Agreed. I love my Tekna model. It's so comfy. The remote app and the 'winter pack' is great. On many an icy evening I've been able to have the car defrosted and toasty before I arrive at the train station while everyone else has to scrape ice from the windshield and wait for the car to demist. So nice to drive, I would say even fun! The kids love the heated seats in the back. And the Bose sound system is absolutely fantastic. All more reasons why I'm more interested in keeping it and giving it a longer life. I'd have to pay mad money for a similar spec on another car if I did change.

I'll just have to decide now what to do with the old battery. I'd like to see it put to good use.

slave1

There was a time when we were all saying end of life in the EV would mean there was still a life left by moving it to home storage but times changed rapidly over the last year or so, LiFfePO4 batteries have plummeted in price and are much much safer alternative

unkel

https://www.boards.ie/discussion/comment/121564885#Comment_121564885

Agreed with LiFePO4 being a cheaper, better, longer lasting and indeed far safer choice for home batteries, but that said, there is still a thriving market for second hand EV battery packs. People use them for many other types of projects, like EV conversions.

Himselfe

https://www.boards.ie/discussion/comment/121564885#Comment_121564885

Yes, it certainly seems to be moving very quickly. I've only really been looking at this properly for a few weeks and I'm finding it difficult to keep up to be honest! I've seen it mentioned regularly that LiFfePO4 batteries are safer, but how 'unsafe' are the lithium ion ones? Should I completely discount using my Leaf battery as storage purely on safety grounds?

A (very) quick Google is giving me prices of roughly €1k+ per KWh for LiFfePO4 batteries and prices from installers seem to be a little more expensive than that, possibly due to markup etc. My old Leaf battery has at least 10-15kWh capacity left in it so I'm trying to weigh up the safety piece as I would essentially be throwing away a large capacity battery to pay a lot of money for safer new tech but with a much lower capacity. The Leaf battery, if I did decide to install it, would be stored outside in a custom casing in a covered area protected from the elements and not attached to the house.

Also, would the relatively slow charge speed generated from solar charging be likely to cause stress to the battery to compromise it in such a way that it becomes a problem?

And thanks to all for the responses. Very helpful. 🙌

unkel

@Himselfe - "Should I completely discount using my Leaf battery as storage purely on safety grounds?"

Yes in my humble opinion you should discount it. Not saying it is always unsafe, but it can easily become unsafe if your setup isn't right, with a proper BMS installed too. If you get a system failure, there can be consequences. And you most certainly should not install it in an area where people live / sleep. In an outhouse or shed maybe where they can do no harm. Tesla refused to do installs of their Powerwalls inside houses. Say no more.

unkel

@Himselfe - "A (very) quick Google is giving me prices of roughly €1k+ per KWh for LiFfePO4 batteries"

Woot? That's insane. You need to hone your Googling skills a bit more 😂 A typical main brand 5kWh pre made server rack battery costs about €1500-2000 incl delivery and all taxes. Install is plug and play. So that is €300-400 per kWh

Or you can go DIY, the cells are now as cheap as €60 + VAT and delivery per kWh. Yes, €60. No typo:

https://eu.nkon.nl/rechargeable/lifepo4/prismatisch/envision-ess-72173207-305ah-lifepo4-3-2v-b-grade.html

PCDub

Using the 305ah Envision cells on NKON you can build a 14+kwh battery for under 2k, including case and bms.

Himselfe

https://www.boards.ie/discussion/comment/121565138#Comment_121565138

Cheers! It seems the solar installers are taking people for a ride, that's a massive saving. I'll have to check this out in more detail. And I like the expandability element. With the pre made server rack battery from a main brand, when you say plug and play will they work with any invertor or will some only play nice with certain brand invertors? Most of the installers I've dealt with to date are pushing Solis invertors.

I think I'm moving towards not using the Leaf battery at this point with the comments people have made on here.

unkel

Depends on the pack and the inverter. But a lot of pre made packs work as standard with the likes of Solis / Sofar / Sunsynk / Deye inverters

Look into DIY though, a lot of us have gone that route, some with zero prior experience of working with batteries. Have a look here:

https://www.boards.ie/discussion/2058246061/10kwh-lifepo4-diy-battery-addition-here-is-my-write-up

gossamerfabric

https://www.driving.co.uk/news/nissan-turns-leaf-ev-into-portable-power-packs/

PCDub

This lad is a bit of genius with the Leaf batteries and other EV Stuff. While it can be done it does take a fair bit of knowledge.

https://www.youtube.com/%40DalasEVRepair/videos

unkel

https://www.boards.ie/discussion/comment/121565560#Comment_121565560

Yep he's done his own Leaf battery upgrades and does them for others as a service too, like Range Therapy. But I think he recently decided to stop that do free himself up for other things and he shared his knowledge online for anyone willing to do it themselves

I don't think the OP wants to take that on though. Not particularly difficult, but it is not without danger and you need some serious equipment to be able to physically get the battery out and in.

PCDub

https://www.boards.ie/discussion/comment/121565598#Comment_121565598

Agreed, really posted to show whats required to do it safely. Yep he dumped all the info on github if anyone wants to have a go. I think a diy lfp battery is the better option for capacity, safety, cost and even form factor.

He has some good videos on upgrading the leaf battery which the OP might find interesting/informative.

graememk

Comparison between battery types for fire and punchure tests

https://youtu.be/Qzt9RZ0FQyM?si=7HgkJ1b-HjUOECaJ

Himselfe

Thanks again everyone for all the great info. I'll take a look at the DIY battery option. It certainly looks very doable. While I'm a capable DIY man I've never really dabbled in anything to do with mains electricity. Maybe now is my chance!

The Leaf battery replacement and a solar installation at home are all scheduled to happen before the month is out. I'll report back on the outcome anyway in case anyone is interested.

unkel

https://www.boards.ie/discussion/comment/121566443#Comment_121566443

Keep us updated!

And technically a DIY battery install has nothing to do with dabbling in mains electricity. You will need a RECI to connect your inverter to the grid, all the DC bits you can do yourself are by definition not mains electricity

Are you going to sell your old Leaf battery on the likes of eBay or adverts?