Feature requests/input for MUXSAN 45kWh replacement LEAF battery

[mux]

It's been a fair number of years since multiple announcements of aftermarket LEAF replacement batteries and, simply put, you still can't buy one. The best option you have right now to replace your Leaf's battery is to get a second hand 40 or 62kWh battery and use Dala's/my CAN bridge firmware to pair it to the car. As arguably the tech originator for a bunch of this stuff, we've been waiting for other parties to come with a good replacement battery option, but it seems like production and financing problems have plagued all the other options. DIY options are now slowly becoming possible from parties like Chooship, but are still reusing the old Leaf BMS and don't have any pack cooling. I don't think that is a workable long-term solution, a lot of the issues with the Leaf packs are down to the BMS and cooling.

So at MUXSAN we've been working on a replacement battery and we'll be announcing this publically soon. It's 45kWh (NMC) and has air cooling, and we offer CCS/CHAdeMO 2.0 charging at up to 100kW as an optional extra. It'll launch in the Netherlands to start, but we're aiming for worldwide shipping (with some liability asterisks). It won't be as cheap as the DIY kits, but not as expensive as our 45kWh extenders. You'll be able to buy one in the 4th quarter of this year and prototypes are going to be on the road and doing publicity 'soon'.

I think I kind of know what Leaf owners want in a hypothetical new battery - a bit more capacity, faster charging, cooling and Leaf Spy Pro support. But of course I'm in my bubble of colleagues in this space, what do YOU want in a replacement battery? This can be hardware or software.

Note that any Leaf Spy Pro feature is going to be dependent on the willingness of Turbo3 to work with us on that (don't get me wrong, he's awesome and really responsive to bugreports etc.).

Big hardware things are probably not going to be feasible, as we're aiming for production in the low hundreds of units per our current businessplan.

 

[FinnishCoffee]

How much will it cost? That is the key number one concern of buyers.

 

[whereswally606]

This is great news Emile, anything for the env200 also?

 

[mux]

This is great news Emile, anything for the env200 also?

Yes, but later than the Leaf. We'll be outfitting our e-NV200 with one over the summer, while the first prototypes in the Leaf will be driving around in May already.

How much will it cost? That is the key number one concern of buyers.

Can't divulge that yet, but we'll be releasing promotional materials, preorders, etc. this month still - and that's going to have prices attached.

By the way, that's not just unwillingness, there's a financing and logistics aspect of the costs that we haven't finalized yet.

 

[FrancoVecchi]

I wish a 50kWh battery at least and a little cooled, so forced air cooling is ok. CSS charging in italy is a must, today. 100Kw of charging power is ok.

 

[whereswally606]

Yes, but later than the Leaf. We'll be outfitting our e-NV200 with one over the summer, while the first prototypes in the Leaf will be driving around in May already.


Can't divulge that yet, but we'll be releasing promotional materials, preorders, etc. this month still - and that's going to have prices attached.

By the way, that's not just unwillingness, there's a financing and logistics aspect of the costs that we haven't finalized yet.

So are you rolling your own bms or are they oem bms with new code on?

 

[MikeinPA]

Great news! Questions:

• For the US, would this be a kit to rebuild an existing pack? How many parts are reused? Time to look for a low ahr donor pack?
• Sounds like there is a new BMS in the works--can a LFP version be a future option?
• I wish for a 20 amp relay & breaker to allow direct access to the main battery that is controlled by the BMS. So the BMS would control whether the relay can be active. The use case is the ability to supplement a house main battery and also to accept solar without having to go through multiple steps.

Just wonderful. Keeping Leafs on the road just makes so much sense. Thank you.

 

[uHu]

Wishes:
1 - More modern cells with less need for cooling.
2 - OVMS-compatibility. (As the Nissan Connect is outdated, OVMS is the way forward - and it also replaces LeafSpy)
3 - About 30 - 40 kWh capacity, for under 6 k €
4 - Choice of a rebuild kit (cells and any other HW), or a complete battery with casing.

Can you deliver?

 

[mux]

So are you rolling your own bms or are they oem bms with new code on?

Our own BMS.

Great news! Questions:

• For the US, would this be a kit to rebuild an existing pack? How many parts are reused? Time to look for a low ahr donor pack?
• Sounds like there is a new BMS in the works--can a LFP version be a future option?
• I wish for a 20 amp relay & breaker to allow direct access to the main battery that is controlled by the BMS. So the BMS would control whether the relay can be active. The use case is the ability to supplement a house main battery and also to accept solar without having to go through multiple steps.

Just wonderful. Keeping Leafs on the road just makes so much sense. Thank you.

Only the shell and external connectors remain, all the insides are replaced. Kits are absolutely a possibility, but with massive, massive liability waivers. In general: if you're at all familiar with how things went with our... let's call them competitors from oceania: this stuff is VERY hard to scale and certify for every market, while keeping prices even remotely reasonable.

LFP or really any other cell is possible in the future, but we've got a supplier and pricing figured out that we'll at least stick with for the first production run. It's risky to change this stuff too much.

We've been toying with the idea of an accessory connector on the pack. Mainly to connect our extender batteries.

Wishes:
1 - More modern cells with less need for cooling.
2 - OVMS-compatibility. (As the Nissan Connect is outdated, OVMS is the way forward - and it also replaces LeafSpy)
3 - About 40 - 50 kWh capacity, for under 6 k €
4 - Choice of a rebuild kit (cells and any other HW), or a complete battery with casing.

Can you deliver?

1 - done and done

2 - OVMS compatibility is definitely on the list.

3 - 6k€ is impossible, that's less than cell cost right now. Keep in mind that the types of cell pricing you see in news articles is not what you pay for a complete battery - for reference, the cheapest automotive name-brand NMC module we can buy right now is about €125/kWh in container quantities.

4 - yep, that's the plan.

 

[rsbrax]

This is good news and seems better than any other option currently available. What locations in the U.S. would be able to install the 45 kWh battery? Would MUXSAN be able to partner with GREENTEC or some other qualified installer?
I have to ask, will the battery be assembled in the Netherlands versus China?

 

[mux]

We haven't had talks with partners in the US yet. More specifically, lots of people have contacted us over the years, but for liability reasons it's always been really hard to seriously engage across the atlantic. That's different now, we will be seeking partners.

With our current selection of materials, everything is produced in Europe and assembled in the Netherlands. Depending on a specific new type of cell that we'd really like to use in the future, the batteries may come from China at some point (and that will be clearly advertised). Assembly will always stay here.

 

[EVPowers]

I spent quite a bit of time getting the current New aftermarket LRN 40 kWh offering out there. And it isn't cheap.

Would certainly be interested in partnering with you when the time comes if you want to reach out to me. There is a ready list of independent US and Canada installers who would be interested in exploring your offering.

EV Powers
608-729-4082
[email protected]

 

[Rx212a]

Would there be a business case proposal for dropping the intended capacity in half?

All of these solutions seem to focus on massive packs compared to the Gen1 leaf.

Here’s what I see.
Better density would give a lower overall weight, improving performance
Lower weight may contribute to reduced consumption, possibly equaling the original 24kwh range
Extra space inside the pack allows for passive air cooling and less loading
Costs would be dropped, and a better economic calculation to improve an older car vs a complete vehicle upgrade - which in most cases is simply cheaper overall.
Shipping costs reduced
Tax costs reduced
Lastly - the range offered by a light weight 20kwh pack would be better than double the range of the vast majority of Gen1 owners who might consider this. If 50m/80km is working for them now, getting back to near double that is a great bonus and extends the life by at least another 10yrs

 

[Eddie16]

1. You said your offering has air cooling. Please clarify. Do you mean forced-air cooling?
2. You should be letting us know what the price will be.
3. You said this is NMC chemistry. Isn't it the case that LFP or LMFP cells would provide a longer-lived pack? (That's what I keep hearing.)

 

[mattLeafzen0]

It's been a fair number of years since multiple announcements of aftermarket LEAF replacement batteries and, simply put, you still can't buy one. The best option you have right now to replace your Leaf's battery is to get a second hand 40 or 62kWh battery and use Dala's/my CAN bridge firmware to pair it to the car. As arguably the tech originator for a bunch of this stuff, we've been waiting for other parties to come with a good replacement battery option, but it seems like production and financing problems have plagued all the other options. DIY options are now slowly becoming possible from parties like Chooship, but are still reusing the old Leaf BMS and don't have any pack cooling. I don't think that is a workable long-term solution, a lot of the issues with the Leaf packs are down to the BMS and cooling.

So at MUXSAN we've been working on a replacement battery and we'll be announcing this publically soon. It's 45kWh (NMC) and has air cooling, and we offer CCS/CHAdeMO 2.0 charging at up to 100kW as an optional extra. It'll launch in the Netherlands to start, but we're aiming for worldwide shipping (with some liability asterisks). It won't be as cheap as the DIY kits, but not as expensive as our 45kWh extenders. You'll be able to buy one in the 4th quarter of this year and prototypes are going to be on the road and doing publicity 'soon'.

I think I kind of know what Leaf owners want in a hypothetical new battery - a bit more capacity, faster charging, cooling and Leaf Spy Pro support. But of course I'm in my bubble of colleagues in this space, what do YOU want in a replacement battery? This can be hardware or software.

Note that any Leaf Spy Pro feature is going to be dependent on the willingness of Turbo3 to work with us on that (don't get me wrong, he's awesome and really responsive to bugreports etc.).

Big hardware things are probably not going to be feasible, as we're aiming for production in the low hundreds of units per our current businessplan.

Man I just want you to know that we appreciate your efforts in the Leafs projects,from your early days of trying to improve your leaf range on the sidewalk of your street, to garage and then stepping up to partner with other like-minded guys to what is today know as MUXSAN. Your YouTube videos inspired me getting a used leaf, knowing that I can always get help with the most expensive part of the car, the battery. So thank you and I wish you all the best in yet another ground breaking adventure,the "45kwh air cooled battery". Thanks and I hope you and your team would pull this through.

 

[mux]

Would there be a business case proposal for dropping the intended capacity in half?

All of these solutions seem to focus on massive packs compared to the Gen1 leaf.

Here’s what I see.
Better density would give a lower overall weight, improving performance
Lower weight may contribute to reduced consumption, possibly equaling the original 24kwh range
Extra space inside the pack allows for passive air cooling and less loading
Costs would be dropped, and a better economic calculation to improve an older car vs a complete vehicle upgrade - which in most cases is simply cheaper overall.
Shipping costs reduced
Tax costs reduced
Lastly - the range offered by a light weight 20kwh pack would be better than double the range of the vast majority of Gen1 owners who might consider this. If 50m/80km is working for them now, getting back to near double that is a great bonus and extends the life by at least another 10yrs

Realistically, it's very hard to make small packs these days. The whole reason the 24kWh pack was a manganese spinel chemistry is the fact that this is basically the only chemistry that can take really high c-rate abuse at any temperature (in discharge) without lithium plating. A ~20kWh net pack that has to regularly discharge at 80kW and charge at 50 in NMC or LiFePO4 would be a high-performance cell, something like the old Yuasa LEV50N cells, and those are still about $250-280/kWh. In the end, you don't end up with a cheaper pack.

They're also not that energy dense. An 811 NMC cell can easily do 260Wh/kg these days, while a 4C cell is maybe 170Wh/kg. Manganese spinel cells aren't available anymore for automotive. So you don't save that much on weight and space in the pack anyway.

While this is a theoretically interesting corner of the market to serve, the abundance of competitive 2C NMC and LFP offerings in the market make it unlikely.

The dirty secret of modern battery manufacture and technological advancements in the space is that chemically, no real advancements have been made in 15 years and all the progress in energy density etc. has been packaging improvements (and all the real tech advancements have been focused on longevity, stability, cost, removal of cobalt - all worthy goals, I'm not trying to diminish this side, just saying cells haven't really gotten fundamentally more energy dense).

1. You said your offering has air cooling. Please clarify. Do you mean forced-air cooling?
2. You should be letting us know what the price will be.
3. You said this is NMC chemistry. Isn't it the case that LFP or LMFP cells would provide a longer-lived pack? (That's what I keep hearing.)

Forced air, either passively or with a heat exchanger to the A/C system in the pack (depending on whether the customer is willing to pay for the work of tapping into the A/C system).

Price TBA, soon.

LFP or LMFP has maybe some limited longevity advantages, but the lifespan of the Leaf pack was never constrained by chemistry. Packaging and thermal management, and arguably the weak BMS, have always been the reasons for limited life. And of course the real reason: we can't get fitting, high-performance LFP modules in decent quantities at a good price with a familiar BMS. All of the L(M)FP market right now is heavily focused on high capacity modules for ESS systems, not automotive.

Man I just want you to know that we appreciate your efforts in the Leafs projects,from your early days of trying to improve your leaf range on the sidewalk of your street, to garage and then stepping up to partner with other like-minded guys to what is today know as MUXSAN. Your YouTube videos inspired me getting a used leaf, knowing that I can always get help with the most expensive part of the car, the battery. So thank you and I wish you all the best in yet another ground breaking adventure,the "45kwh air cooled battery". Thanks and I hope you and your team would pull this through.

Thanks! And if I knew how hard all of this would be I would have thought twice (and probably did it anyway) before starting my company. As they say: hardware is hard.

 

[DougWantsALeaf]

Mux,
Ever consider building/ seeking a modified Leaf traction battery cover which has some basic forced air cooling. Even a little air movement within the battery compartment would make long distance in the Leaf easier.

 

[mux]

Mux,
Ever consider building/ seeking a modified Leaf traction battery cover which has some basic forced air cooling. Even a little air movement within the battery compartment would make long distance in the Leaf easier.

A customer of mine tried this! But there were two main issues:
(1) the Leaf battery isn't built to have a well-defined airflow path, or really any airflow. It's all very densely packed without any place to put a convenient blower or axial fan.
(2) The rear stack of batteries is just a terrible, terrible design decision. Almost no matter how much airflow you get in the pack, the middle cells in the rear stack are never going to be able to get rid of their heat and you'll end up with the same bathtub-shaped temperature/health distribution there.

So without a real option to put in a fan, he opened up the service disconnect hole, modified the plastic piece and put a blower motor inside the car to blow air into the pack. For all the effort, there was almost no improvement in rear stack temps (the front stacks did get a lot better though).

-----------

From a business perspective, it's also pretty hard to get this to work. Say you can use that extra ~inch of space above the pack and design a spacer or new battery cover with some air baffles. Now you have a fairly large manufactured piece that you need to make, which in small quantities will cost easily $500. There's a decent amount of labor cutting through the gasket and reapplying it, and there's some amount of risk/liability you need to assume in case you or your mechanics screw up and water enters the pack after a failed reseal. You're also adding moving parts to the battery that can fail or cause noise issues.

It's hard to imagine all of this being cheap, it's going to have to cost $1000+ at minimum, and then you haven't made any money and probably don't have actual product insurance. And this definitely isn't something you can do at a random independent shop, because for the 2 customers that may want this done, they'll need to purchase a bunch of specialized equipment to do the work.

A lot of the types of hacks discussed on this forum are fine if you do them yourself, but once you make a business out of it, it's very hard to do at a reasonable price.

 

[NickoSynergy]

A customer of mine tried this! But there were two main issues:
(1) the Leaf battery isn't built to have a well-defined airflow path, or really any airflow. It's all very densely packed without any place to put a convenient blower or axial fan.
(2) The rear stack of batteries is just a terrible, terrible design decision. Almost no matter how much airflow you get in the pack, the middle cells in the rear stack are never going to be able to get rid of their heat and you'll end up with the same bathtub-shaped temperature/health distribution there.

So without a real option to put in a fan, he opened up the service disconnect hole, modified the plastic piece and put a blower motor inside the car to blow air into the pack. For all the effort, there was almost no improvement in rear stack temps (the front stacks did get a lot better though).

-----------

From a business perspective, it's also pretty hard to get this to work. Say you can use that extra ~inch of space above the pack and design a spacer or new battery cover with some air baffles. Now you have a fairly large manufactured piece that you need to make, which in small quantities will cost easily $500. There's a decent amount of labor cutting through the gasket and reapplying it, and there's some amount of risk/liability you need to assume in case you or your mechanics screw up and water enters the pack after a failed reseal. You're also adding moving parts to the battery that can fail or cause noise issues.

It's hard to imagine all of this being cheap, it's going to have to cost $1000+ at minimum, and then you haven't made any money and probably don't have actual product insurance. And this definitely isn't something you can do at a random independent shop, because for the 2 customers that may want this done, they'll need to purchase a bunch of specialized equipment to do the work.

A lot of the types of hacks discussed on this forum are fine if you do them yourself, but once you make a business out of it, it's very hard to do at a reasonable price.

Great information and really admire your work on all the developments, I'm building an EV Land Rover, based on a 2019 40Kwh Leaf, the battery pack and charging using a Resolve_EV controller's a challenge, as then I discover later Leaf won't run Chademo with that controller, may have to use an older PDM, but the info above regarding the cooling on the rear section of the battery pack is interesting. In this EV conversion, it would be necessary to split the cells up and position around the vehicle, so my guess is, this would help to some degree, but significantly so?

 

[DougWantsALeaf]

A customer of mine tried this! But there were two main issues:
(1) the Leaf battery isn't built to have a well-defined airflow path, or really any airflow. It's all very densely packed without any place to put a convenient blower or axial fan.
(2) The rear stack of batteries is just a terrible, terrible design decision. Almost no matter how much airflow you get in the pack, the middle cells in the rear stack are never going to be able to get rid of their heat and you'll end up with the same bathtub-shaped temperature/health distribution there.

So without a real option to put in a fan, he opened up the service disconnect hole, modified the plastic piece and put a blower motor inside the car to blow air into the pack. For all the effort, there was almost no improvement in rear stack temps (the front stacks did get a lot better though).

-----------

From a business perspective, it's also pretty hard to get this to work. Say you can use that extra ~inch of space above the pack and design a spacer or new battery cover with some air baffles. Now you have a fairly large manufactured piece that you need to make, which in small quantities will cost easily $500. There's a decent amount of labor cutting through the gasket and reapplying it, and there's some amount of risk/liability you need to assume in case you or your mechanics screw up and water enters the pack after a failed reseal. You're also adding moving parts to the battery that can fail or cause noise issues.

It's hard to imagine all of this being cheap, it's going to have to cost $1000+ at minimum, and then you haven't made any money and probably don't have actual product insurance. And this definitely isn't something you can do at a random independent shop, because for the 2 customers that may want this done, they'll need to purchase a bunch of specialized equipment to do the work.

A lot of the types of hacks discussed on this forum are fine if you do them yourself, but once you make a business out of it, it's very hard to do at a reasonable price.

Mux

Thank you for the detailed response. Yes the front cells almost have enough cooling in modest climates now. In my 600 mile in a day trips, at the end, those front cells can be 20+ degrees (F) or more cooler than the rear stack.

My second dream idea would be to design an extender pack that fits into the empty space where a spare tire goes in some.markets (not in the US or EU I think). It's just wasted space.right now, and if you could get a design with 8-10 kWh into that space it would be a nearly no trade offs way of expanding range.

Thank you for all you do for the Leaf community.