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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?

#81

Post by hinkley »

benzible wrote: post #21
dylan604 wrote: post #9

Without being a battery chemistry expert, why do these battery packs become not useful for an EV yet could still be useful for energy storage. They keep saying that 80% of life becomes unusable for EV, but that's still a lot of life. Is it that grid energy is more of a constant drain while the EV is lots of hard pulls (for lack of better wording)? In an EV, the battery cannot provide the higher volts being requested…

It's not just about capacity (80% is still a lot), it's that degraded batteries lose their ability to deliver high current under load—so acceleration suffers and voltage sags under hard pulls. For grid storage, you're doing slow, steady charge/discharge cycles over hours, so the same battery that can't handle aggressive driving anymore works perfectly fine. Plus, grid storage has virtually unlimited space and no rang…

> For grid storage, you're doing slow, steady charge/discharge cycles over hours.

Only if the feed in is a bottleneck. For peak shaving you could go faster.

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

#82

Post by [deleted] »

bryanlarsen wrote: post #2

This is less useful than most people expected. Redwood has been struggling because the expected battery turnover is not occurring. EV batteries are lasting a long time, so they stay in the car are and not being recycled or reused in any quantity yet. If EV batteries last 20+ years in EV's, it'll be > 2040 before there are significant numbers of EV batteries available to recycle or reuse. https://www.geotab.com/blog/e…

[deleted]

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

#83

Post by xattt »

cogman10 wrote: post #20
ACCount37 wrote: post #8

Earlier quoted context omitted.

A lot of the early EV battery life projections were based on Nissan Leaf Gen 1. Which had a horrendous battery pack that combined poor choice of chemistry, aggressive usage and a complete lack of active cooling. When EVs with good battery pack engineering started hitting the streets, they outperformed those early projections by a lot. And by now, it's getting clear that battery pack isn't as much of a concern - with…

I'll defend the leaf a little. LiPo batteries were quiet expensive when it was initially released. NiMH was really the only option in town. And with a lower energy density battery that's also heavier, adding a cooling system would have also added a bunch of weight to the already heavy car with a barely usable range of 100 miles. Gen 2, however, had no excuses. They had every opportunity to add active cooling and they…

NiMH was used in Priuses for a very long time, and these seem to have lasted for ages.

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

#84

Post by pfdietz »

apendleton wrote: post #72
epistasis wrote: post #27

Earlier quoted context omitted.

There's currently no technological path for fusion to be cheaper than fission. It would require a technological breakthrough that we have not yet imagined. And already, solar plus storage is cheaper than new nuclear. And solar and storage are getting cheaper at a tremendous rate. It's hard to imagine a scenario where fusion could ever catch up to solar and storage technology. It may be useful in places with poor sola…

> It would require a technological breakthrough that we have not yet imagined. Maybe, but not necessarily. The necessary breakthrough might have been high-temperature superconducting magnets, in which case not only has it been imagined, but it has already occurred, and we're just waiting for the engineering atop that breakthrough to progress enough to demonstrate a working prototype (the magnets have been demonstrate…

High temperature superconducting magnets are not a panacea for the problems with DT fusion. Those issues follow from limits on power/area at the first wall, and the needed thickness of the first wall; these ensure DT reactors will have low volumetric power density, regardless of the confinement scheme used.

With HTSC magnets, a tokamak much smaller than ITER could be built, but ITER is so horrifically bad that one can be much better than it and still be impractical.

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

#85

Post by torginus »

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…

My new batteries were about 250EUR/kWh - my 10KWh unit cost 2500 EUR - scaling it up to a decent used 5 year old EV price - you can have one for 15k with 60+ kWh batteries, so I'd say it's at a very similar price.

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

#86

Post by ericd »

hnaccount_rng wrote: post #41
Rebelgecko wrote: post #17

Earlier quoted context omitted.

I've been intrigued by used solar panels for sale, seems like you can get an amazing price for ones that are only lightly degraded. Is there a downside, or do you just mean that it isn't popular currently?

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.

Yeah, we paid more for the little bits of metal that held up the panels than for the panels themselves (aluminum, but still).

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

#87

Post by JumpCrisscross »

bryanlarsen wrote: post #2

This is less useful than most people expected. Redwood has been struggling because the expected battery turnover is not occurring. EV batteries are lasting a long time, so they stay in the car are and not being recycled or reused in any quantity yet. If EV batteries last 20+ years in EV's, it'll be > 2040 before there are significant numbers of EV batteries available to recycle or reuse. https://www.geotab.com/blog/e…

> Redwood has been struggling because the expected battery turnover is not occurring

Redwood pitched recycling. But its principal business was primary production. (Processed black mass is analogous to lithium ore.) They're struggling because demand for American-made batteries remains low.

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

#88

Post by numpad0 »

formerly_proven wrote: post #58
MrRadar wrote: post #40

Earlier quoted context omitted.

Every generation of the production Nissan Leaf has used lithium batteries. AFAIK no modern (~post-2000) mass-produced (>10k units sold) EV has ever used NiMH or lead-acid batteries. Edit: Checking Wikipedia to verify my information, I found out that Nissan actually sold a lithium-battery EV in 1997 to comply with the same 90s CARB zero-emissions vehicle mandate that gave us the GM EV-1: https://en.wikipedia.org/wiki/…

EVs no, but I think some Toyota hybrids (which are of course not even PHEVs) still use NiMH. Toyota tends to be very tight-lipped about their batteries and their sizes (or rather, lack thereof).

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 types of information that didn't drive clicks. Language barrier would have effects on it too, that Toyota is a Japanese company and US is an export market, but it's fundamentally the same phenomenon as citizen facing government reports that never gets read and often imagined as being "hidden and withheld from public eyes", just a communication issue.

1: https://www.toyota.com/priuspluginhybrid/features/mpg_other_...

2: https://www.motortrend.com/news/toyota-aqua-prius-c-hybrid-b...

3: https://car.watch.impress.co.jp/docs/news/1339263.html

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

#89

Post by megaman821 »

JohnLocke4 wrote: post #19
bryanlarsen wrote: post #2

This is less useful than most people expected. Redwood has been struggling because the expected battery turnover is not occurring. EV batteries are lasting a long time, so they stay in the car are and not being recycled or reused in any quantity yet. If EV batteries last 20+ years in EV's, it'll be > 2040 before there are significant numbers of EV batteries available to recycle or reuse. https://www.geotab.com/blog/e…

In 2040 fusion energy advancements will have gotten far enough to be the next technological step and make this redundant anyway

The steam generator that the fusion generator connects to might be more expensive than solar at this point. That would be even if fusion cost nothing and had infinite amounts of fuel, there would be no customers for its energy on a sunny afternoon.

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

#90

Post by jbm »

ACCount37 wrote: post #8
bryanlarsen wrote: post #2

This is less useful than most people expected. Redwood has been struggling because the expected battery turnover is not occurring. EV batteries are lasting a long time, so they stay in the car are and not being recycled or reused in any quantity yet. If EV batteries last 20+ years in EV's, it'll be > 2040 before there are significant numbers of EV batteries available to recycle or reuse. https://www.geotab.com/blog/e…

A lot of the early EV battery life projections were based on Nissan Leaf Gen 1. Which had a horrendous battery pack that combined poor choice of chemistry, aggressive usage and a complete lack of active cooling. When EVs with good battery pack engineering started hitting the streets, they outperformed those early projections by a lot. And by now, it's getting clear that battery pack isn't as much of a concern - with…

I am a bit more concerned about batteries now as opposed to an year ago.

We had this article from Elektrek [1] about battery issues in South Korea. When I asked my local electric maintenance shop [2, sorry for the FB link], they said they have started seeing the same issue in Model 3s and Ys in Canada as well. (They also said that it is too early to tell how common it would become)

This may bode well for recycling since the issues is an unbalance, not the whole pack failing.

[1] https://electrek.co/2025/10/14/tesla-is-at-risk-of-lossing-s...

[2] https://www.facebook.com/groups/albertaEV/posts/248558844207...

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