EVs Enhanced battery pack option for New Zealanders, other markets too?

Wow, this is pretty cool and I wish them well as they appear to be a mature and trustworthy company who has already innovated with other EV solutions to date.

An aftermarket LEAF pack, with chemistry options and active cooling is fantastic, provided they can offer these solutions for a reasonable cost.

https://youtu.be/2eLe92OAeoU

Hope they release pricing details soon, as well as info on what markets they intend to serve first.

Note to EVs Enhanced - don't forget about Western Canada, please!

Amazing.. can't wait for these to ship globally.

Wow. Will be interesting but who knows if it'll be cheap enough in the US to make sense?

At least these guys have demonstrated technical prowess, unlike Fenix.

I took the survey on their website. They are estimating about 1/3rd the cost of the car, so guessing 10-15K for a new pack.

If you'd be neat if they could buy the Leaf from Nissan sans battery and install their custom pack as a kind of Leaf++.

Very interesting video of this new pack concept.

The "Green" version is their first approach using Lithium Iron Phosphate cells. They are showing 16 modules, or "Blades" in this pack, so how many cells do you think are in a module or the pack?

i think 7 cells per module is too few and 8 per module is too many depending upon how high you charge the cells. Last time i messed with LFP the full cell voltage was about 3.33; there is no benefit to overcharge them except to reduce their life.

nlspace said:

Very interesting video of this new pack concept.

The "Green" version is their first approach using Lithium Iron Phosphate cells. They are showing 16 modules, or "Blades" in this pack, so how many cells do you think are in a module or the pack?

i think 7 cells per module is too few and 8 per module is too many depending upon how high you charge the cells. Last time i messed with LFP the full cell voltage was about 3.33; there is no benefit to overcharge them except to reduce their life.

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Agreed, LiFePO4 was an interesting choice but I'm guessing this reflects their focus on the domestic market first as most of NZ has a moderate climate.

I would think that 7 cells per module would be required (403V/(16*3.6V)), since LiFePO4 cells fully charged are usually 3.6V (3.7V OK too) and the stock LEAF pack fully charged is about 403V.

For a fully discharged pack, the low voltage cutoff of their LiFePO4 pack could be set to about 288V (2.57V x 7 x 16) to match the stock pack. That would leave some capacity buffer at the bottom end as LiFePO4 cells can be safely discharged to 2.5V

What great news that a capable outfit is taking up this project. I found the video very informative, well made, no-nonsense and at just the right technical level for an EV geek. I was really struck by the comment that they expect the green pack to outlive the vehicle. That's quite a claim - and great news, especially since they appear to be supporting V2X - but I trust them that they've done the homework.

Also amazing was how the green/blue/red packs use different chemistries and BMS. This bodes well for the future if/when solid state Li batteries become available.

goldbrick said:

I was really struck by the comment that they expect the green pack to outlive the vehicle.

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LFP is the preferred choice in solar projects for that reason. If treated properly, 80% capacity after 15 years is possible. With their plan to thermally manage their packs, that should provide optimal pack conditions year round.

LFP tolerates temps up to about 130F well, so mostly the thermal management will be useful for keeping the pack above freezing temps during winter months. For colder climates, that could eat up a lot of range though.

So, I wouldn't want an LFP pack if I lived in a location where well below freezing temps are the norm during winter. However, if they sell a 40 kWh or more LFP pack for under $10k USD, with a 10 year or better warranty, I would still be interested

Making a LiFePO4 pack available opens up a lot of options for people like me who a) don't mind doing vehicle maintenance, b) don't drive much, c) are looking for the lowest cost per year, and d) don't like fossil fuels. With one Leaf on the road, and some spare parts stored away from salvage (brake master cylinder for example), I could contain transportation cost for many years.

I wonder if the "blades" will be populated before shipping to US, or whether it makes more sense to have the parts shipped to an assembly point for integration? Can't wait to see this hardware, maybe own some. Also, I would expect that the EVsEn packs will initially be available from the shops already doing battery swaps.

Can't wait for when they'll release global sales options! This is exactly what we need!

Google says that LFP has about 70% the volumetric density of NMC.
Since the NZ folks say 74 kWh for NMC, that implies about 45 kWh packs made from LFP

Perfect !

DC charging is going to be a soft spot. If they stick with CHAdeMO at 125 Amps most places and 200 Amps occasionally, It looks like rates will be mediocre at best since nominal voltage is 3.2V. That would work out to 38 - 60 kW. I'm a bit surprised that they are bothering with liquid cooling, but perhaps it will be a cheap and not too efficient system, sized for the application. Air cooling makes a lot more sense to me.

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The strange thing here is that this design is *exactly* what Nissan should do for LEAF 3.0 along with CCS.

I watched the video again and right around the 5:29 mark you can see what look like blue/red hoses that connect to each battery module. I assume these are cooling pipes. At about the 6:20 mark you can see the blue/red hoses leaving the case. I didn't catch any notice of where they connect or how cooling is provided. At the end, when they are standing in front of what I assume is a prototype, I couldn't see the red/blue hoses that left the case in the animation. Looking forward to more.

One thing may concern me. Isn't this the outfit that bought Nissan's claim about the 30kwh pack's problems being entirely a BMS software issue? They even provided test data that "proved" it, yet Nissan was wrong, and if they are the same company, they were wrong as well...

I'm cautiously optimistic on this one; I know they have fairly decent engineering resources to work on this. However, the previous replacement battery effort didn't go anywhere and this one is looking pretty advanced by comparison. I feel like there's still a decent chance of this project stranding if they don't get enough early buy-in. From a technical perspective, I don't doubt this will be a fine battery.

For reference; we're (obviously) also working on a replacement battery project within MUXSAN behind the scenes, and there is basically no way we can offer 40+kWh for less than about €15k at the moment, including thermal management. Part of this has to do with the currently really tight battery market (new cells cost about €175/kWh and have ~4-6 month lead times - including a compliant BMS and everything else you're easily looking at €275/kWh) and part has to do with homologation costs and timelines (homologating a new battery costs about €50-100k per model, and that only gets you into most EU countries, with significant markets like the USA and Norway not covered).

I *suspect* EVs Enhanced is aiming at an affordable price point by not doing any homologation and just selling an uncertified product. This will work in a few markets like NZ and a fair number of US states, but will not work for e.g. Europe. That's what we're aiming at though, so in due course we'll hopefully cover part of that market (if we can get certification to work out, otherwise our project will strand somewhere at the end of 2022).

mux said:

For reference; we're (obviously) also working on a replacement battery project within MUXSAN behind the scenes, and there is basically no way we can offer 40+kWh for less than about €15k at the moment, including thermal management.

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Why is thermal management a given if LFP cells are used ?
I am (perhaps naively) under the impression that if fast DC charging is sacrificed, decent life can still be obtained from LFP.

And related, how about LFP with ambient air ventilation ?

In my opinion, and this is strictly because of how I view the utility and future of EVs, you are not really doing a service to your customers by JUST extending the autonomy of a car without also significantly improving its charging characteristics. Especially on the leaf with its legacy CHAdeMO connection, IMO you're skating on thin ice by providing another non-thermally managed pack. Moreover, because developing and supporting an EV battery replacement is a very long-term commitment (it takes ~2 years from start to finish to develop the thing, then at least a year to turn a profit and at least the lifespan of the battery - say 8 years - of support even if you stop production after that year), it's important to consider not just the needs of customers now, but those of customers - essentially - 8 years from now.

In 8 years, those LEAFs will still function just fine mechanically, I have no doubt about that. But nobody is going to use a car with 50kW (really more like 44, and only peak) fast charging for anything beyond a grocery runabout car. That's honestly not functionally different from an unmodified car, so why even bother with the extra range. From a sustainability and GHG abatement perspective, you've not really improved the world at that point. People still need a second car to do serious car things like drive 200 miles - especially in car-dependent places. I want people to avoid needing another car with all the emissions and traffic implications that may have.

Now, thermal management is not just battery cooling, it's also heating. And that's really where the LFPs are horrible and should be thermally managed. They suffer massively from lithium plating at even moderately low temperatures (e.g. 0-10C), so you get maybe 0.25C allowable charge rates (~10kW) at 0C and 0.5C at 10C (~20kW). Considering that the car also has higher consumption at low temperatures, this makes the car nigh unusable for anything beyond its initial autonomy, and even threatens slow charging speeds at freezing temperatures.

So for both usability and technical reasons, I expect an LFP pack to be fully thermally managed.

In the future, I basically expect three tiers of battery replacements to be competing for people's dollars:
- Salvage packs, cheap and shitty, sold at like $50-100/kWh
- Salvage-like new packs, with similar capacity to old Leaf packs, maybe even recycling their shells to keep costs down, with no thermal management, sold at about the current level of salvage packs ~ $150-200/kWh
- Re-engineered packs with higher capacity, much faster charging, thermal management, coupled with e.g. CCS retrofits, sold at $250+/kWh

And both from a business and user's perspective, I expect only that last one to be acceptable, with the others mostly being a cheap fix for actually broken batteries to tide somebody over for a year until they buy a new car.

Re-engineered packs with higher capacity, much faster charging, thermal management, coupled with e.g. CCS retrofits, sold at $250+/kWh

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There's likely a niche market for that, but a modular design that works on more than one EV seems highly unlikely.

So, developing bespoke after market packs at this price point will never be a high or even moderate volume market. At best, a nice local niche for independent shops in some regions (where there are a lot of older EVs) rather than a global market.

Unfortunately, I think it's likely that in all but the larger cities, older EV packs will be repurposed/recycled and the car itself will be scrapped.

Also, given their high depreciation, the analytical part of my brain reasons that trading up for a newer EV model year is the smarter choice vs upgrading the pack. In a similar vein, I wouldn't replace the engine or transmission in my second car, a 2011 Hyundai Elantra Touring, as the cost of doing that exceeds what the car is worth.

I really hope I'm wrong and that many owners of older LEAFs will purchase replacement packs to extend the life of these cars for many more years.

One possibility is that older EVs will depreciate to the point that they are worth almost nothing. That could be attractive to a new owner, who could purchase a car for super cheap and then spend $10k for a new pack.

I posted this already in the CANbus reverse engineering thread: https://www.mynissanleaf.com/viewtopic.php?f=44&t=4131&start=670#p615911

I am a little annoyed at EVs Enhanced. I put a comment on their youtube video "Glad to see you're using the open source .DBC file Looking forward to any contributions to it!"

They promptly deleted my comment. I understand since they are probably looking for investors, It needs to look like its all their work. But still I'm a little pissed off, so much time is still going into maintaining these reverse engineering efforts without much contribution back to the community.

It hasn't gone unnoticed that they haven't made any contributions to the collective knowledge about these cars; never did provide any information about their previous swapping effort; and certainly not supplied any technical details of this new concept.

Karma has a way of rewarding folks to get what they deserve. :lol:

Dala, I agree, that is complete crap.