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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?

#211

Post by jopsen »

Moto7451 wrote: post #141
adrianN wrote: post #135

Earlier quoted context omitted.

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 u…

We did 12.000 km in our id.4 last year.

I suspect it'll die due to rust. But yes, might take a while. Even in Denmark where we salt the roads in a winter.

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

#212

Post by close04 »

formerly_proven wrote: post #166
numpad0 wrote: post #88

Earlier quoted context omitted.

Tends to be tight lipped??? It is in the catalog[1]! It is more that American consumers aren't tech obsessed than Toyota being reluctant to share. Even just looking at online media reports[2][3] clearly sourced from some exact same press event, it is obvious that US English equivalents are much lighter in content than Japanese versions. They're putting the information out, no one's reading it. It's just been the type…

Despite your ??? and ! the only article you posted that's about hybrids (and not PHEVs) mentions nothing about battery capacity.

> Battery capacity (kWh) 13.6

It's under Weights/Capacities but you have to expand the section yourself, no way to link directly to it.

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

#213

Post by formerly_proven »

close04 wrote: post #212
formerly_proven wrote: post #166

Earlier quoted context omitted.

Despite your ??? and ! the only article you posted that's about hybrids (and not PHEVs) mentions nothing about battery capacity.

> Battery capacity (kWh) 13.6 It's under Weights/Capacities but you have to expand the section yourself, no way to link directly to it.

The page you are referring to is literally titled "Plug-In Hybrid Specifications"

/out

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

#214

Post by ben_w »

noosphr wrote: post #61
epistasis wrote: post #51

Earlier quoted context omitted.

You have that exactly backwards: solar + storage is what will give us energy abundance at less money than we could ever imagine from nuclear fission or fusion. China is winning the AI Cold war because it's adding solar, storage, and wind at orders of magnitude more than nuclear. I'm not sure who's doing your supposed "envisioning" but there is no vision for cheap abundant energy from fusion. Solar and storage deliver…

China has been building out nuclear capacity at 5% a year for 25 years. 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. The other big item is hydro power, which China has a ton of untapped potential for. Unfortunately for the West every good river has already been damed so we can't follow them there.

> 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.

They can't sell as much as they would like, specifically to the USA, due to tariffs/trade war, but there's a much bigger world out there than just the US, and the overall exports are up over the last five years: https://www.canarymedia.com/articles/solar/chart-chinas-sola...

There's a Chinese-made Balkonkraftwerk sitting a few meters away from me on my patio, it cost €350, of which €50 was delivery and another €50 was the mounting posts, the remaining €250 got me 800 W of both panel and inverter.

> Unfortunately for the West every good river has already been damed so we can't follow them there.

For generation, yes. For storage, no.

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

#215

Post by pfdietz »

epistasis wrote: post #120
apendleton wrote: post #103

Earlier quoted context omitted.

In terms of cost of materials to build a reactor, sure, that seems right. But most of the cost of fission is dealing with its regulatory burden, and fusion seems on track to largely avoid the worst of that. It seems conceivable that it ends up being cheaper for entirely political/bureaucratic reasons.

Regulatory costs and waste disposal are not significance cost centers for nuclear, at least as far as I can tell from any cost breakdowns. One doesn't need super high quality welding and concrete pours becuase of regulations as much as the basic desire to have a properly engineered solution that lasts long enough to avoid costly repairs. Take for example this recent analysis on how to make the AP1000 competitive: htt…

> let's hear how to change

One approach would be to reduce the size of the containment building by greatly reducing the volume of steam it must hold. This would be done by attaching Filtered Containment Venting Systems (FCVS) that strip most of the radioactive elements from the vented steam in case of a large accident.

The containment building is a significant cost driver, costing about as much as the nuclear island inside of it.

If such a system had been attached to the reactors that melted down at Fukushima exposure could have been reduced by maybe two orders of magnitude. And if the worst case exposure is that low, perhaps much more frequent meltdowns could be tolerated, allowing relaxation of paperwork requirements elsewhere.

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

#216

Post by sehansen »

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…

EVs are probably not going to depreciate as much in the future. The depreciation mostly happened because new electric cars have become cheaper.

As an example, let's say a 2 year old car is only worth 80% of an identical brand new car. The old car was bought for $50k at new, leading to a expected depreciated value of $40k. But since manufacturing has become more efficient a brand new car of the same model can be had for the same $40k. Nobody would be willing to buy the 2 year old car at the same price. You'd probably have to charge only $32k [0]. But then it looks to you as if it has depreciated 36%.

The question is how much new electric cars will fall in price in the future. And if they continue to fall, at some point the dollar value of the depreciation will be too small to care about.[1]

0: $32k = 0.8 * $40k

1: E.g. if a new car is $10k, $3600 in depreciation over two years is annoying, but not a big deal.

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

#217

Post by jopsen »

pfdietz wrote: post #49
hnaccount_rng wrote: post #41

Earlier quoted context omitted.

In addition to my sibling comment: The cost of the panels is a rather small fraction of the total cost of a typical installation. Most of that cost ist labor, some regulatory requirements and the inverter. Whether you pay a factor of 2 for the panels or not typically doesn't matter. In other words: Reusing used panels will only ever be able to safe you a minuscule amount.

The low cost of the modules themselves has led to the suggestion of cost optimized DC-coupled PV systems being used to directly drive resistive heaters. The cost per unit of thermal energy in a cost optimized system moderate scale system (> residential, Low cost modules allow one to do away with things like optimally tilted modules and single axis tracking. The modules can also be tightly packed, reducing mounting an…

I've heard of farmers doing this, well I think they actually had an inverter. But limits on how much they could dump into the grid, meant that they had lots of surplus electricity and installing resistive heating was very cheap.

Even if they don't have surplus electricity all the time.

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

#218

Post by ben_w »

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.

> It's terrible for China, less than 15%.

55.4 GW per 277 GW is an (annual) capacity factor of 20%, so the response here is "yes, and?"

> And more importantly, you can have _weeks_ with essentially zero solar power when you need it most.

Half the country is a mid-latitude desert. What makes you think the whole country has "weeks" with zero solar? And it does have to be the whole country in this case, because one thing a centrally planned economy can do well is joining up the infrastructure, which in this case means "actually make the power grid the USA and the EU keep wringing their hands over".

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

#219

Post by sehansen »

eloisant wrote: post #175
dukeofdoom wrote: post #25

Seems like the market is going the hybrid route. It's kind of easy to see why, best of both worlds. Some BYD hybrids have crazy ranges like 1500 km on a tank of gas. The more practical car is winning. They put in a much small battery in these for fast charge, and the daily commute range. And you have gas, for longer trips. Maybe smaller batteries would be better for grid-scale storage too. If they're lighter and easi…

No, hybrid is just a temporary solution until the charging infrastructure becomes good enough. And depending where you live, it's already there. Hybrid is the worse of both worlds in a way. You have a combustion engine to maintain, that is useless when using electricity. You have a heavy battery useless when using your combustion engine. You don't get all the benefits of electric, and you don't get all the benefits o…

Exactly this. Here in Denmark, 48k plug-in hybrids were sold in 2020, falling to 4k in 2025. The same numbers for fully electric cars were 38k in 2020 and 144k in 2025. Once the public charging infrastructure was here, the change was dramatic. I bought my first electric car this year and I haven't had trouble finding a public AC charger when I needed to, which is often since I live in a condo.

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

#220

Post by Xemplolo »

adwn wrote: post #202
Xemplolo wrote: post #188

Earlier quoted context omitted.

You are just not able to comprehend basic writing styles. The author is a journalist and not the expert he is interviewing thats the first thing. So why would you even evaluate the journalists 'expertise' if you get the answers from the experts. And secondly what he probalby meant was that what if this company can 'push out' all active lifecycle before they recycle them. This is called a metapher.

> And secondly what he probalby meant was […] If they can't precisely convey the intended meaning in written words, they shouldn't be a journalist.

Journalists write for an audiance which normally gets it.

You just might not be one of them.

And no no one needs to write everything so that everyone always gets it.

I for example do not write blog articles for kids. I also don't write very technical blog articles for people outside of tech.

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