[HN Gopher] Can "second life" EV batteries work as grid-scale en...
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       Can "second life" EV batteries work as grid-scale energy storage?
        
       Author : davidw
       Score  : 86 points
       Date   : 2025-10-23 18:15 UTC (4 hours ago)
        
 (HTM) web link (www.volts.wtf)
 (TXT) w3m dump (www.volts.wtf)
        
       | bryanlarsen wrote:
       | 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/ev-battery-health/
        
         | jeffbee wrote:
         | There is one constant to all these conversations and that is
         | Silicon Valley tech dudes are grossly misinformed about the
         | lifecycle of things. Solar panels don't wear out, batteries
         | don't wear out as fast as they used to. This is evidenced both
         | by undertaking weird dead-end startup ideas, and being
         | susceptible to propaganda about the supposed downsides of solar
         | energy and batteries.
        
         | pfdietz wrote:
         | So, basically the same reason recycling of PV modules hasn't
         | taken off.
        
           | Rebelgecko wrote:
           | 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?
        
             | jeffbee wrote:
             | I think they were referring to the fact that the chief
             | reason there is not large-scale PV panel recycling is that
             | very few panels have ever been retired. It turns out that
             | short of physical destruction by hail etc a PV panel does
             | not degrade beyond economic usefulness simply by being out
             | in the sun. In fact some panels actually get more powerful.
             | The surprising-to-some conclusion of NREL's PV Lifetime
             | Project is that the economic lifetime of a PV panel is
             | basically forever.
        
             | hnaccount_rng wrote:
             | 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.
        
               | pfdietz wrote:
               | 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, < utility scale)
               | may be in the range of $3-5/GJ, very competitive with
               | natural gas. Low cost maximum power point trackers would
               | be useful; inverters would not be needed.
               | 
               | 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 and
               | wiring costs.
        
               | maxerickson wrote:
               | What's the proposed system design? For example, in
               | January, I get about 9 hours of sunlight and have an
               | average daily high of 25 F. I'm gonna need to store heat
               | somehow or another.
        
               | hinkley wrote:
               | These days it's a stack of microinverters. Which are not
               | cheaper but do improve array efficiency outside of idea
               | conditions. But that's another up front cost.
        
               | ericd wrote:
               | Yeah, we paid more for the little bits of metal that held
               | up the panels than for the panels themselves (aluminum,
               | but still).
        
             | duskwuff wrote:
             | How much of a difference does it actually make in terms of
             | the all-inclusive price of installation (e.g. panels,
             | inverters, mounting hardware, and labor)?
             | 
             | (Asking because I genuinely don't know, not because I have
             | a specific answer in mind.)
        
               | hinkley wrote:
               | Find an installer who will warranty work using third
               | party let alone used solar panels and then we can talk.
        
         | dylan604 wrote:
         | From TFA:
         | 
         | David Roberts
         | 
         | When did automotive batteries become the majority of your input
         | by volume?
         | 
         | Colin Campbell
         | 
         | That is a good question.
         | 
         | David Roberts
         | 
         | Was it recent or was that early on?
         | 
         | Colin Campbell
         | 
         | I would say the transition to EV batteries dominating what we
         | received, it's been in the last year or 18 months.
         | 
         | David Roberts
         | 
         | So the front edge of a very large wave of batteries has begun
         | to arrive?
         | 
         | Colin Campbell
         | 
         | Yeah, the wave is out there, it's coming. The waters have
         | finally started to arrive at the beach here.
        
           | bryanlarsen wrote:
           | Reading between the lines of the corporate speak will
           | validate my point. Redwood was founded in 2017.
        
             | dylan604 wrote:
             | "It's the largest microgrid in North America and it's the
             | largest second-energy storage site in the world. So that's
             | like you said at the top, it's a 12-megawatt AC,
             | 63-megawatt-hour grid supporting about 2 or 3 megawatts of
             | data centers and run by solar. So all the energy comes from
             | another 12 megawatts of solar."
             | 
             | Sure, so while not supplying power to a city, they are
             | proving this is viable. Just because it's not "turn off the
             | coal plants now" moment doesn't mean this isn't a very good
             | direction. Everyone has to start and grow. I don't
             | understand the whole shit on something because it's not an
             | immediate solve. If these guys waited until 2040 to start
             | the business, well, that'd just be dumb. It essentially
             | sounds like capacity will just continue to increase year
             | over year, maybe around 2040 there will be a huge spike.
             | Doesn't seem like anything is wrong here.
        
           | jeffbee wrote:
           | He's just talking his book. Their deployment this year was
           | 1/4000th share of the BESS market.
        
             | dylan604 wrote:
             | Battery Energy Storage System for anyone else like me that
             | has no knowledge of this world and their acronyms.
        
         | ACCount37 wrote:
         | 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 some of the better designs, like in early
         | Teslas, losing about 5-15% of their capacity over a decade of
         | use.
        
           | cogman10 wrote:
           | 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 still decided to go with just air
           | cooling.
        
             | wcfields wrote:
             | On the used market you'll find absolutely cooked
             | (literally) Leafs whose first life was in Arizona and
             | barely have enough range to back out of the driveway.
        
               | londons_explore wrote:
               | I have a gen 1 leaf with a remaining range of about 500
               | yards if you drive gently...
               | 
               | I use it in my driveway to make it look to thieves like
               | someone is home (round me, houses with no car get broken
               | into).
        
             | MrRadar wrote:
             | 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/Nissan_R%27nessa#Nissan_Altra
        
               | formerly_proven wrote:
               | 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).
        
               | numpad0 wrote:
               | 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
        
               | avhception wrote:
               | It's nice to get a reminder about this problem once in a
               | while, I've fallen into the trap myself at times.
        
             | ACCount37 wrote:
             | Leaf Gen 1 didn't have NiMH. It had a lithium-based battery
             | chemistry, but some bastard offshoot of it. One that really
             | didn't fare well under high current draw, or deep
             | discharge, or high temperatures, or being looked at wrong.
        
             | xattt wrote:
             | NiMH was used in Priuses for a very long time, and these
             | seem to have lasted for ages.
        
           | floxy wrote:
           | 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-science-
           | beh...
        
           | jbm wrote:
           | 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/248558844
           | 207...
        
         | whatever1 wrote:
         | We are only 5-6 years into the car ev market. Tesla model 3
         | started being sold in 2018 in meaningful numbers
        
           | cogman10 wrote:
           | Still have mine. Battery capacity is around 80% of the new
           | capacity. I'm not planning on switching anytime soon as it's
           | got plenty of range still. I'll probably swap the pack out
           | when it hits 70% in the next 2 or 3 years.
        
             | bryanlarsen wrote:
             | It probably will take a lot longer than that to hit 70%.
             | Degradation on Tesla batteries slows down considerably
             | after it hits 85%.
             | 
             | there are exceptions, though.
        
         | p1necone wrote:
         | > "most people"
         | 
         | "most people" even now are just parroting dumb FUD they read on
         | facebook. You really shouldn't give any weight to the opinions
         | of laypeople on topics that are as heavily propagandized and
         | politically charged as renewable energy.
        
         | p0w3n3d wrote:
         | Tesla batteries fail after 8 years at least from models up to
         | 2014
        
           | stetrain wrote:
           | The number of Teslas sold up to 2014 is less than 1% of all
           | Teslas sold.
           | 
           | Tesla has an 8-year battery and drivetrain warranty but they
           | don't necessarily fail after that date.
        
           | trhway wrote:
           | Prius Plugin 2015 (last year of that model) - full
           | charge/discharge at least 3-4 times a week, currently still a
           | bit more than 80% of capacity (granted the battery seems
           | somewhat overbuilt, yet it is normally does 10-15C which is
           | much tougher mode than in a pure EV where 2-3C is usually
           | enough and only high-end Teslas and the likes would do 5-6C).
           | There has been large continuous improvement in lithium
           | batteries over the last couple decades.
        
           | Sohcahtoa82 wrote:
           | [citation needed]
        
         | JohnLocke4 wrote:
         | In 2040 fusion energy advancements will have gotten far enough
         | to be the next technological step and make this redundant
         | anyway
        
           | epistasis wrote:
           | 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 solar resources, like fission is now, but
           | that's a very very long time from now.
        
             | noosphr wrote:
             | The low energy future that was envisioned is not happening.
             | 
             | The AI arms race, which has become an actual arms race in
             | the war in Ukraine, needs endless energy all times a day.
             | 
             | China is already winning the AI cold war because it adds
             | more capacity to its grid a year than Germany has in a
             | century.
             | 
             | If we keep going with agrarian methods of energy production
             | don't be surprised that we suffer the same fate as the
             | agrarian societies of the 19th century. Any country that
             | doesn't have the capability to train and build drones on
             | mass won't be a country for long.
        
               | epistasis wrote:
               | 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 it today, fusion only delivers
               | it in sci fi books.
               | 
               | Nuclear is 20th century technology that does not fit with
               | a highly automated future. With high levels of
               | automation, construction is super expensive. You want to
               | spend your expensive construction labor on building
               | factories, not individual power generation sites.
               | 
               | Building factories for solar and storage lets them scale
               | to a degree that nuclear could _never_ scale. Nuclear has
               | basically no way of catching up.
        
               | pfdietz wrote:
               | > sci fi books
               | 
               | I blame these for the unquestioned belief that fusion is
               | desirable. It's a _trope_ because it enables stories to
               | be told, and because readers became used to seeing, not
               | because science fiction has a good track record on such
               | things.
               | 
               | The fact that the volumetric power density of ARC is 40x
               | worse than a PWR (and ITER, 400x worse!) should tell one
               | that DT fusion at least is unlikely to be cheap.
               | 
               | With continued progress down the experience curve, PV
               | will reach the point where resistive heat is cheaper than
               | burning natural gas at the Henry Hub price (which doesn't
               | include the cost of getting gas through pipelines and
               | distribution to customers.) And remember cheap natural
               | gas was what destroyed the last nuclear renaissance in
               | the US.
        
               | formerly_proven wrote:
               | It's hard to imagine a form of energy production less
               | desirable than fusion.
               | 
               | Okay, sure, burning lignite and using the exhaust as air
               | heating in the children's hospital. You got me.
        
               | noosphr wrote:
               | 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.
        
               | epistasis wrote:
               | > 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 year versus all time. And then in the
               | _first half_ of 2025, China installed another 212GW of
               | solar. In six months.
               | 
               | Nuclear is a footnote compared to the planned deployment
               | of solar and wind and storage in China.
               | 
               | Anybody who's serious about energy is deploying massive
               | amounts of solar, storage, and some wind. Some people
               | that are slow to adapt are still building gas or coal,
               | but these will be stranded assets far before their end of
               | life. Nuclear fusion and fission are meme technologies,
               | unable to compete with the scale and scope that batteries
               | and solar deliver every day. This mismatch grows by the
               | month.
        
             | Dylan16807 wrote:
             | Fission is expensive for regulation reasons more than
             | technological reasons, so if fusion doesn't face the same
             | barriers then it could be cheaper than fission.
             | 
             | But I agree that it doesn't look like fusion is going to be
             | cheap any time soon.
        
             | apendleton wrote:
             | > 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
             | demonstrated but a complete reactor using them hasn't yet).
             | 
             | Or it might be that the attempts at building such a
             | prototype don't pan out, and some other breakthrough is
             | indeed needed. It'll probably be a couple of years until we
             | know for sure, but at this point I don't think there's
             | enough data to say one way or the other.
             | 
             | > And already, solar plus storage is cheaper than new
             | nuclear.
             | 
             | It depends how much storage you mean. If you're only
             | worried about sub-24h load-shifting (like, enough to handle
             | a day/night cycle on a sunny day), this is certainly true.
             | If you care about having enough to cover for extended bad
             | weather, or worse yet, for seasonal load-shifting (banking
             | power in the summer to cover the winter), the economics of
             | solar plus storage remain abysmal: the additional batteries
             | you need cost just as much as the ones you needed for daily
             | coverage, but get cycled way less and so are much harder to
             | pay for. If the plan is to use solar and storage for _all
             | generation_, though, that's the number that matters.
             | Comparing LCoE of solar plus daily storage with the LCoE of
             | fixed-firm or on-demand generation is apples-and-oranges.
             | 
             | I think solar plus storage absolutely has the potential to
             | get there, but that too will likely require fundamental
             | breakthroughs (probably in the form of much cheaper
             | storage: perhaps something like Form Energy's iron-air
             | batteries).
        
               | pfdietz wrote:
               | 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.
        
               | epistasis wrote:
               | And these are not new issues, they've been known for more
               | than 40 years, but never addressed. From the 1983 Led
               | 
               | > But even though radiation damage rates and heat
               | transfer requirements are much more severe in a fusion
               | reactor, the power density is only one-tenth as large.
               | This is a strong indication that fusion would be
               | substantially more expensive than fission because, to put
               | it simply, greater effort would be required to produce
               | less power.
               | 
               | https://orcutt.net/weblog/wp-content/uploads/2015/08/The-
               | Tro...
        
             | BurningFrog wrote:
             | The regulatory hurdles are probably bigger than the
             | difficult enough technological ones you mention.
        
           | bee_rider wrote:
           | This is like a "fusion is only 20 years away" (or 15 in this
           | case) joke, right?
        
             | hinkley wrote:
             | It used to be 30. So fifty more years?
        
               | marcosdumay wrote:
               | Yep, it was 30 years at the 60s. If it keeps halving
               | every 85 years, we'll get it approximately never :)
        
           | megaman821 wrote:
           | The steam generator that the fusion generator connects to
           | might be more expensive than solar at this point. That would
           | me even if fusion cost nothing and had infinite amounts of
           | fuel, there would be no customers for its energy on a sunny
           | afternoon.
        
         | JumpCrisscross wrote:
         | > _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.
        
         | Theodores wrote:
         | The typical EV industry trade show has a small handful of cars
         | and a vast amount of tangential businesses including many
         | finance options, a vast amount of home charger gizmos, fast
         | charging gizmos, electricity suppliers and the companies
         | promising grid-scale storage, either from actively used cars or
         | recycled EV batteries. There is a vast constellation of this
         | stuff, with specialist insurance companies that nobody really
         | asked for outnumbering the car brands or even e-bike brands
         | present.
         | 
         | In time there will be consolidation. This constellation of EV
         | startup bottom-feeders will be decimated along with the
         | 'excuses' to not make money.
         | 
         | I don't think the problem is that EV batteries are lasting
         | longer, it is just that the EV market from before the Model 3
         | came along is miniscule. Hence not many second hand batteries
         | to recycle.
         | 
         | As for EV batteries and their availability, when was the last
         | time you saw an OG Tesla Model S with the fake grill? Those
         | cars used to be everywhere, but where are they now? The German
         | EVs that came out to compete, for example, Taycan and eTron,
         | those things are not going to last the distance since the
         | repairs cost a fortune and the parts supply is limited.
         | 
         | All considered, there will come a time before 2040+ when there
         | are large quantities of these electric car batteries to
         | upcycle, by which time the EV business will be consolidated
         | with only a few players.
         | 
         | If there was money in recycling cars then every auto
         | manufacturer would be in on it.
        
       | dylan604 wrote:
       | 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 within rating, but a
       | grid is never demanding peak performance?
        
         | MarioMan wrote:
         | Space and weight are serious constraints in the car space, but
         | not such a big deal on the side of a house. That's how they
         | retain their usefulness.
         | 
         | 80% could indeed be plenty of usable life for _your_ EV use
         | cases, but it strongly depends on usage patterns. More
         | degradation means more trips to the charger on a road trip. It
         | means trips that you'd regularly make just charging at home at
         | the end of day now require you to plug in at the destination
         | too. It means more range anxiety as a whole.
        
         | HWR_14 wrote:
         | For an EV you want a high energy density, because it impacts
         | range. For grid storage, density doesn't matter as much.
        
         | benzible wrote:
         | 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 range
         | anxiety, so if you need 25% more packs to hit your capacity
         | target, you just stack them in a warehouse where real estate is
         | cheap.
        
           | miahi wrote:
           | Also, batteries will degrade faster over time when they start
           | to degrade, because they need more frequent charging. Their
           | internal resistance increase and that promotes heat buildup
           | during fast charging/discharging, another thing that promotes
           | degradation. Slow charge/discharge cycles also help with heat
           | management.
        
           | ramses0 wrote:
           | Looking forward to the grid-scale warehouse fire of battery
           | packs popping off...
        
             | dylan604 wrote:
             | They claim to have taken the Moss Landing fire into account
             | with how they are placing their batteries. We won't know if
             | they've really solved the problem or not until their first
             | battery pack experiences a runaway thermal event.
        
           | hinkley wrote:
           | > 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.
        
       | KaiserPro wrote:
       | > Can "second life" EV batteries work as grid-scale energy
       | storage?
       | 
       | Yes
       | 
       | is it profitable? probably not.
       | 
       | Looking at the price for brid battery storage, and its dropping
       | precipitously. The cost isn't as much in the batteries them
       | selves, it packaging, placing and then controlling them.
       | 
       | For example if you want to have a 200Mwhr 100Mw storage site,
       | you'll need to place it, join it to the grid, all doable. Then
       | you need the switch gear to make it work as you want it to.
       | 
       | For day ahead, 30 minute trading, thats fairly simple.
       | 
       | For grid stabilisation, thats a bit harder, you need to be able
       | to lead/match/lag the grid frequency by n degrees
       | instantaneously. which is trivial at a few kw, much harder at
       | 100Mw
        
         | nop_slide wrote:
         | Sounds like what https://www.basepowercompany.com/ is doing
        
       | 1970-01-01 wrote:
       | Betteridge's law of headlines finally fails? TL;DR: Yes, but you
       | can also make it 'not work' if you choose to politicize the tech
       | solution to the energy problem.
        
       | dukeofdoom wrote:
       | 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 easier to handle.
        
         | pinkgolem wrote:
         | i have heard that hybrid's have a maintanance problem?
         | 
         | is not a concern, double the technologie in the same space?
        
           | dukeofdoom wrote:
           | Not sure about that, since I did never owned one either. But
           | I watched a review BYD car yesterday. And it's supper nice.
           | 
           | https://www.youtube.com/watch?v=_6bqgR3NRHE&t=1s
        
           | dukeofdoom wrote:
           | It's possible it might actually be more reliable long term,
           | once the technology matures. For example, in cold weather the
           | gas engine might heat the battery for better battery
           | performance, maybe even extend its life if it prevents it
           | from being drawn down too much. The gas engine, would also
           | likely last longer since its not used for daily commutes.
           | 
           | "In many PHEV systems, there are different modes:
           | 
           | Electric mode (EV mode): The vehicle runs purely on the
           | electric motor(s) and battery until the battery depletes to
           | some extent.
           | 
           | Hybrid/Parallel mode: Both the petrol engine and electric
           | motor(s) work together to drive the wheels, especially under
           | high load, higher speeds or when battery is low. Ithy
           | 
           | Series mode (in some designs): The petrol engine acts only as
           | a generator to charge the battery or power the electric
           | motor(s), and the wheels are driven by the electric motor(s).
           | 
           | For the BYD Leopard 5 (and many BYD PHEVs) the petrol engine
           | can drive the wheels (i.e., it is not purely a generator). It
           | is part of the drive system, especially when high power or
           | long range is needed.
           | 
           | At the same time, it likely can assist with charging the
           | battery or maintaining battery state of charge (SOC) when
           | needed (for example, to keep the battery at some reserve
           | level or in "save" mode). User-reports show that the petrol
           | engine will kick in to support the electric system, charge
           | the battery, or assist the drive under certain conditions" -
        
           | toast0 wrote:
           | 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 motor/generator that also starts the engine;
           | it's less likely to get worn out, because it's built for
           | continuous use.
           | 
           | In my PHEV, it has a 'toyota synergy' style 'e-CVT' which
           | eliminates gear selection and should be very low maintenance
           | (although mine had to be replaced under a service bulletin
           | due to bearing failure because of manufacturing error) again
           | nicer than an ICE. But some hybrids have a more traditional
           | transmission.
           | 
           | Certainly, you can do ICE only or EV only, but there's a lot
           | of room to use the ICE for things it's good for, and the EV
           | for things it's good for, and blend where there's overlap.
        
           | duskwuff wrote:
           | Not that I'm aware of. I've heard that many hybrids actually
           | require less maintenance - for instance, the car can use
           | electric power for hard acceleration instead of stressing the
           | engine, so oil tends to last longer, and regenerative braking
           | causes the friction brakes to wear out more slowly.
        
           | numpad0 wrote:
           | It's not like reliable gas cars ever had substantial
           | maintenance problem in the gas part. So removing the gas part
           | didn't do much in practice.
           | 
           | People do/did have frustrations with gas car mannerisms and
           | mental approachability, like, everything was written in a mix
           | of translated foreign language documents and borderline
           | insane gearhead languages. That lead them to imagine that
           | removing the gas part would drastically change the industry,
           | in their favor.
           | 
           | But, in the end, gas cars are good with regular maintenance
           | for something like 100k miles over 8 years, so, I wouldn't
           | know what consumer product were more reliable than a gas car
           | in the first place.
        
       | iwanttocomment wrote:
       | I've got a 13 year old EV and nobody has told me how to cash my
       | EV in for reusable energy storage. (No, seriously, hit me up.)
        
         | bryanlarsen wrote:
         | Just sell it though normal channels. If your battery is with
         | more than your car then there would be people making money on
         | the arbitrage.
        
           | iwanttocomment wrote:
           | I totally get that, but as the owner, perhaps _I 'd_ like to
           | make the money on the battery before the arbitragers.
        
       | torginus wrote:
       | 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 source of cells that accidentally happens to
       | be able to drive itself around.
       | 
       | Imo V2G, and V2H is unnecessary and add too much complication, I
       | think for the future, solar inverters already have the necessary
       | hardware and certifications to be able to take power and safely
       | connect to the grid - something that requires different hardware
       | and standards compliance in basically every country (yes even
       | within the EU).
        
         | irons wrote:
         | In the US, V2L limits your ability to output power from the car
         | to about 1500 W. It's not going to power your house as more
         | than a stopgap, even if you do have supplementary house
         | batteries. V2H/V2G justify their complexity by solving that
         | problem, along with all the ancillary grid benefits.
        
           | torginus wrote:
           | Not sure if that's the case - however doing V2L requires the
           | manufacturer to add an inverter to the car, and making that
           | powerful probably adds extra cost most customers wouldn't
           | pay. TI just looked it up and my Ioniq can only do about 2kW
           | sustained - but since this charges the house battery, that's
           | enough - idle load is just a couple hundred watts.
        
           | Dylan16807 wrote:
           | A typical house averages less than 1500W. And most of the
           | higher usage overlaps the sun being out. So if you have
           | supplemental house batteries to handle bursts then 1500W of
           | V2L can go a very long way.
        
         | kieranmaine wrote:
         | Very interesting - I did not know this was possible. A few
         | questions:
         | 
         | 1. Does the solar inverter do away with the need for a V2G or
         | V2H unit?
         | 
         | 2. What are the limitations vs a dedicated V2G/H unit?
         | 
         | 3. Is generator input on your solar inverter a common feature
         | across inverters?
        
           | torginus wrote:
           | 1. It does. The only issue is that the car can only output
           | about 2kW sustained (this is a model limitation). That's fine
           | since I have batteries in the house.
           | 
           | 2. Tbh not super familiar with V2G/V2H, other than it being
           | super expensive for both the wall box and the car (only high
           | end models tend to support it)/
           | 
           | 3. No idea, but it's not a high end feature, I wouldn't count
           | on any inverter to just have it, but if you're looking to buy
           | one that does, I don't think you'll be breaking the bank.
           | 
           | Imo the future is for solar inverters to offer a dedicated DC
           | car charger port, as once again all the hardware is already
           | in there.
        
             | kieranmaine wrote:
             | Thanks for the answers. I used to work for a EV smart
             | charging company (Kaluza) that ran a V2G trial. V2G was
             | financial success for the users, but I always thought the
             | wall box was a potential blocker. I don't think the 2kW
             | output is a big issue as the customer could still reduce
             | there load when required, but the elimination of a wall box
             | makes onboarding much easier.
             | 
             | As long as the inverter can also provide charging this
             | definitely has some potential.
        
         | archi42 wrote:
         | 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 about 14kWh per day, I
         | didn't bother doing the math and just ordered it.
         | 
         | These are 280Ah 16S 51.6V packs, based on the EVE LF280K. In an
         | enclosure, with a BMS (Seplos, 200A) and a dedicated balancer.
         | They are good for 6000 cycles at 140A or less [each]. Mind
         | these were both part of small bulk orders - I think each time
         | we ordered 6 to 8 of these, which reduced shipping costs.
        
           | torginus wrote:
           | 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.
        
       | dreamcompiler wrote:
       | This is great! Now I have a place to take my old puffy Li-Ion
       | batteries.
       | 
       | https://www.redwoodmaterials.com/recycle-with-us/
        
       | almosthere wrote:
       | We don't need ev batteries for this. We just need cheap enough
       | LifePo4 so we're not burning more shit down. Prismatics from
       | China are a start, Salt batteries showing some promise next.
        
       | tedk-42 wrote:
       | > but what if they could drain every last drop of energy from
       | those batteries before recycling them?
       | 
       | Again batteries are an energy store and not an energy source. The
       | fact the author cannot distinguish that makes the their opinion
       | less credible.
        
         | hinkley wrote:
         | All I can think is embodied energy? That's weird.
        
       | Lucian6 wrote:
       | Having worked extensively with battery systems, I think the grid
       | storage potential of second-life EV batteries is more complex
       | than it appears. We found that typical EV batteries retain 70-80%
       | capacity after 8-10 years of vehicle use, but the real challenge
       | is standardization and integration. Different manufacturers use
       | vastly different battery management systems (BMS) and cell
       | configurations - a Tesla pack is fundamentally different from a
       | Nissan Leaf pack.
       | 
       | The economics are interesting though. New grid storage batteries
       | cost around $200-300/kWh, while second-life EV batteries can be
       | acquired for $50-100/kWh. However, you need to factor in
       | significant integration costs (~$50-75/kWh) to build compatible
       | BMS systems and thermal management. We also found cycle life
       | degrades about 20% faster in repurposed packs compared to new
       | ones, likely due to accumulated stress patterns from automotive
       | use.
       | 
       | Has anyone here successfully integrated mixed second-life
       | batteries at scale? I'm particularly curious about how you
       | handled thermal management across different pack designs while
       | maintaining safe operating parameters.
        
       | kibitzor wrote:
       | >So top of the list for us, of course, designing this thing is
       | safety.
       | 
       | Funny issue I learned after talking to a founder at a similar
       | company: although the battery packs were certified safe for cars
       | (passing crash tests, wild heat differences from AK to AZ, people
       | sitting on top of the battery packs in the car) ... the founder
       | had issues re-certifying the batteries for safe use in a static
       | location for grid storage.
       | 
       | The certification process treated his company like the batteries
       | were made from scratch even though they used the same BMS/coolant
       | lines/etc. already proven and tested.
       | 
       | It's clear you still need strong safety regulations and practices
       | in the rare case there's an event, but the founder noted the grid
       | storage industry regulations were adding redundant safety testing
       | and slowing down adoption. The founder also added it's difficult
       | to compete on cost even with effectively free used EV batteries
       | in this startup space of grid storage against the low cost of
       | Chinese made grid-specific batteries due to the added testing +
       | custom hardware + space constraints and other items. (Caveat: I
       | didn't fact check any of their statements)
        
       | HocusLocus wrote:
       | In an ice storm and cold cloudy snap that sweeps the country, NO
       | lithium batteries will save the grid. I'm weary of this tunnel
       | vision of the absurd. The only 'storage' that works is to pump
       | water uphill with 'surplus' energy, and there is not and never
       | will be a surplus. And these evaporartion tanks are on a scale
       | that ecologists have to remember countless horror stories (eg.,
       | Glenn Canyon Dam). And of course there's always "mfft!" (another
       | scheme with no numbers behind it so it's credible because I'm
       | talking about it).
       | 
       | The last time there was anything rational on the table was Perry
       | under the Trump administration's 30-day rule proposal (
       | https://www.nucnet.org/news/nuclear-is-vital-to-us-national-...
       | ). It gave a hard industry incentive to any supplier who can have
       | 30 days' fuel on site. This means nuclear and coal. This was no
       | gimmick, it was the first time anyone faced reality about
       | National Security as related to Energy for the grid and survival.
       | And now AI datacenter yadda yadda, we're also talking about the
       | _luxury_ of keeping schools heated in Winter. Adverse weather
       | even for a week is grid down game over for wind and solar. Proven
       | natural gas are ~300 years, joy! As soon as they get around to
       | sending pregnant whales across the ocean (losing ~20% of the gas-
       | energy in cooling) it may even last 50 years! Before we have to
       | go to endless war again.
        
       | AtlasBarfed wrote:
       | I think car cells will be much more useful if they are packaged
       | as replacement batteries for all the various battery powered
       | tools, ebikes, etc.
       | 
       | There's a consumer profit margin to absorb the repackaging and
       | teardown.
       | 
       | Maybe for home grid batteries they'll work too. Again, a consumer
       | margin.
       | 
       | Sodium Ion and other grid-specific storage will simply be too
       | cheap for secondhand EV batteries to compete. And the retiring
       | cells won't be any better in density and will be less safe than
       | the higher density sodium ion and LFP that is hitting the market.
        
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