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Can “second life” EV batteries work as grid-scale energy storage?

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Re: Can “second life” EV batteries work as grid-scale energy storage?

#141

Post by Moto7451 »

adrianN wrote: post #135
floxy wrote: post #47

Earlier quoted context omitted.

Don't forget that the original Leaf pack was only 24 kWh. So if you assume a ~1000 full-equivalent-charge-cycles lifespan, then the large Gen2 62 kWh pack will live 2.5 times longer than an original 24 kWh pack. If you average 3.5 miles/kWh, the 24 kWh battery will be expected to last somewhere around 84,000 miles. While the 62 kWh pack will last for 217,000 miles. https://coolienergy.com/lfp-vs-nmc-batteries-the-sci…

Why would you only assume 1000 cycles? Is the chemistry that bad? The LFP battery on my balcony is rated for 5000 cycles iirc.

LFP does have a lot more cycles in them by the nature of the chemistry. However EV grade NMC aren’t terrible either.

Depth of discharge and charge rate affect LFP specifically in such a way that if you keep them a good margin above cutoff voltage, relatively cool (60C and under, and do 1C and lower charging you can get 10,000 cycles per their data sheets. The same sheets will also list lower cycle counts for harder use that lines up with the standards used for earlier cells. Basically I think we’ll find a lot of gently to moderately used hardware will last a long time.

Whatever a believable use case looks like will probably end up on those data sheets and it wouldn’t surprise me if we see 15,000 and 20,000 cycles advertised for cells intended in low charge and discharge use cases (probably not cars but maybe home energy storage).

My Taycan has an ongoing battery issue relating to LG Pouch cells but its construction rather than composition that is the culprit. The same compositions from LG in prismatic and cylindrical models, the only models they sell now, so far haven’t been a mess for car makers.

Re: Can “second life” EV batteries work as grid-scale energy storage?

#142

Post by user_7832 »

torginus wrote: post #31

Personally speaking, having just bought an Ioniq 5 and installing solar at home what I see as the near future improvement is adding V2L functionality, which I can hook up to the generator input of my solar inverter, essentially adding another 60kWh buffer to my grid storage. Considering how expensive residential batteries are and how quickly EVs depreciate, I think soon it'll be cheaper to get a used EV as a cheap so…

> Imo V2G, and V2H is unnecessary and add too much complication

I believe that's more a function of auto makers (and charger cos) not trying to do much about it (and grid cos not caring), than a technical issue. The benefits (especially if V2G) are quite significant.

I doubt any car owner will say no to earning revenue from something that costs them almost nothing. The problem is more of "how do we get there at scale". (Disclaimer, I studied this topic in my thesis.)

Re: Can “second life” EV batteries work as grid-scale energy storage?

#143

Post by adwn »

archi42 wrote: post #68
torginus wrote: post #31

Personally speaking, having just bought an Ioniq 5 and installing solar at home what I see as the near future improvement is adding V2L functionality, which I can hook up to the generator input of my solar inverter, essentially adding another 60kWh buffer to my grid storage. Considering how expensive residential batteries are and how quickly EVs depreciate, I think soon it'll be cheaper to get a used EV as a cheap so…

Residential batteries are not that expensive anymore, at least not all of them. That's a misconception I also held until a few years ago ;-) My first 14.3 kWh pack cost about 2800$ DDP from China, delivered 03/2023. For that one I did calculate how long it took for amortization, which I projected at about 5 years. The second, identical pack was delivered 08/2024 and cost 2000$ DDP. Since we got an EV that's drawing a…

Today you can already get 51.2 V, 16 kWh batteries complete with balancer and BMS from a European supplier for 1200 € (1400 US$): https://www.nkon.nl/novat/nkon-ess-eco-s-51-2v-16-1kwh-thuis...

Re: Can “second life” EV batteries work as grid-scale energy storage?

#144

Post by noosphr »

cyberax wrote: post #138
epistasis wrote: post #67

Earlier quoted context omitted.

> Solar and wind capacity had shot through the roof in the last five years because they can't sell hardware to the west any more. "can't sell hardware??" hah! I've never heard that weird made-up justification, where did you pick it up from? China installed 277GW of solar in 2024, capacity factor corrected that's 55.4 GW of solar power. That's equivalent to the entire amount of nuclear that China has ever built. One y…

> China installed 277GW of solar in 2024, capacity factor corrected that's 55.4 GW of solar power. The problem is not just the mean capacity factor, but the capacity factor in _winter_. It's terrible for China, less than 15%. And more importantly, you can have _weeks_ with essentially zero solar power when you need it most.

This is not an issue in China as they overprovision demand by 50 percent. Their grid can run off baseload generation alone in their 2060 plan.

Trying to explain that a grid build by electrical engineers, rather than financial engineers, has resilience build in to people whose whole idea about electricity generation is greenwashed bullshit from McKinsey and Co is at best a waste of time and at worst an excellent way to raise one's blood pressure.

Re: Can “second life” EV batteries work as grid-scale energy storage?

#146

Post by pfdietz »

cyberax wrote: post #140
pfdietz wrote: post #108

Earlier quoted context omitted.

Relaxed regulatory burden doesn't seem to be making fission competitive in China; renewables are greatly overwhelming it now, particularly solar. We might ask why regulations are so putatively damaging to nuclear, when they aren't to civil aviation. One possibility is that aircraft are simply easier to retrofit when design flaws are found. If there's a problem with welding in a nuclear plant (for example) it's extrem…

Regulation is not a problem, and even the construction costs are not terrible. We can take the Rooppur NPP as a base, it produces reliable energy at 6-7 cents per kWh. The reason for cost overruns is simply because NPPs are one-off products, the Western countries don't have a pipeline for NPP production. For comparison, utility-scale solar with 16 hours of storage is 21 cents: https://www.utilitydive.com/news/higher-…

If I understand correctly, the cost/year of an engineer in India is maybe 1/3rd that in the US, and for general labor the disparity is even larger. So it shouldn't be too surprising NPP construction in India is cheaper than in the US. India doesn't have a large NPP pipeline, they just have cheaper labor.

Re: Can “second life” EV batteries work as grid-scale energy storage?

#147

Post by toast0 »

Marsymars wrote: post #123
toast0 wrote: post #50

Earlier quoted context omitted.

Eh, my PHEV has a 2 year oil change interval, which is longer than my ICE only cars. You should probably bring in your EV every 2 years to get things looked at too. The engine in a hybrid should live an easier life compared to an ICE. No extended idle, mostly running in the power band, etc. There are lots of different ways to setup the hybrid system, but typically, rather than a small stater motor, you have a larger…

Ford Escape? I have a friend that needed the transmission on his 2023 PHEV replaced under warranty... no service bulletin, but mechanics caught a manufacturing error at a regular service. Hopeful my hybrid Maverick doesn't have similar problems.

2014? Ford C-MAX energi TSB 16-0105 [1] (although there's a similar TSB 22-2396 [2] with a wider range)

I'd just say, if it starts making bearing noises (loudest around 15mph), check in and get yelly. Cause apparently they keep screwing them up. HF35 is designed and built by Ford for Ford, so they really should have everything they need to do it right. sigh

I saw a picture somewhere where they had an extra hole carved through the casing from this, worked fine until it breached and the fluid came out, then it died pretty quick.

[1] https://static.nhtsa.gov/odi/tsbs/2016/SB-10092366-5448.pdf

[2] https://www.tsbsearch.com/Ford/22-2396

Re: Can “second life” EV batteries work as grid-scale energy storage?

#148

Post by adwn »

Lucian6 wrote: post #66

[dead]

> New grid storage batteries cost around $200-300/kWh

That doesn't sound right. You can already get high-quality, prismatic LFP cells for ~50 US$/kWh [1] from European distributors at low-volumes, so bulk from China should be even cheaper. And there's no way that balancing and BMS cost an additional 150-250 US$/kWh at scale, not even a tenth of that.

[1] https://www.nkon.nl/novat/eve-lf230-prismatic-230ah-230a-lif...

Re: Can “second life” EV batteries work as grid-scale energy storage?

#149

Post by overfeed »

Lucian6 wrote: post #66

[dead]

> Having worked extensively with battery systems, I think the grid storage potential of second-life EV batteries is more complex than it appears.

Complex, by t very much doable. Toyota implemented such a system with enough packs to power a Mazda factory [1]

> However, you need to factor in significant integration costs (~$50-75/kWh) to build compatible BMS systems and thermal management.

Shouldn't this be a once-off cost per battery-pack version? Or was this your armortized cost for your deployment capacity. If you've written the BMS for a 2019 Model 3 Panasonic battey pack once, won't you reuse it for all the subsequent battery packs of the same model/SKU?

1. https://news.ycombinator.com/item?id=44998010

Re: Can “second life” EV batteries work as grid-scale energy storage?

#150

Post by apendleton »

cyberax wrote: post #140
pfdietz wrote: post #108

Earlier quoted context omitted.

Relaxed regulatory burden doesn't seem to be making fission competitive in China; renewables are greatly overwhelming it now, particularly solar. We might ask why regulations are so putatively damaging to nuclear, when they aren't to civil aviation. One possibility is that aircraft are simply easier to retrofit when design flaws are found. If there's a problem with welding in a nuclear plant (for example) it's extrem…

Regulation is not a problem, and even the construction costs are not terrible. We can take the Rooppur NPP as a base, it produces reliable energy at 6-7 cents per kWh. The reason for cost overruns is simply because NPPs are one-off products, the Western countries don't have a pipeline for NPP production. For comparison, utility-scale solar with 16 hours of storage is 21 cents: https://www.utilitydive.com/news/higher-…

> The reason for cost overruns is simply because NPPs are one-off products

But there's no fundamental reason they _have_ to be one-off products. They just historically have been for at least partly regulatorily motivated reasons: because each reactor's approval process starts afresh (or rather, did until quite-recent NRC reforms), there's little advantage in reuse, and because many compliance costs are both high and fixed, there's an incentive to build fewer huge reactors rather than more small ones, which makes factory construction difficult to achieve and economies of scale hard to realize.

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