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

volts.wtf

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

#201

Post by ericd »

dzhiurgis wrote: post #184
ericd wrote: post #86

Earlier quoted context omitted.

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

IDK sounds like you got ripped off. I diy'd and panels were cheap of course, but fittings were perhaps 3-5x cheaper. Inverter is typically same as your panels (hybrid, grid-tied are quite a bit cheaper).

Maybe, but these aren’t fittings, they’re ground mounts with large screws that screw into the ground to hold the entire array down, including under high wind (and have to come with PE stamped system-level engineering drawings talking about things like rated wind load of the whole array to pass building inspections).

But yeah, at the end of the day, just bent bars of aluminum with ground screws and bolts to hold the corners of the panels, versus the technological marvels of the solar panels they hold.

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

#202

Post by adwn »

Xemplolo wrote: post #188
tedk-42 wrote: post #42

> 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.

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.

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

#203

Post by mcbishop »

adwn wrote: post #148
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...

Right, $200-300/kWh is more the range for ~16kWh residential stationary energy storage systems.

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

#204

Post by beAbU »

cogman10 wrote: post #197
beAbU wrote: post #156

Earlier quoted context omitted.

Your 2018 tesla has a battery SOH of 80%? How many km's on the clock, and how often do you fast charge if you dont mind me asking? To me that SOH stat sounds really bad!

270,000 km. And fast charging about 3 times a year. If I were to guess, the main factor harming the battery is my garage gets pretty hot in the summer (37 or 38C)

That is quite high mileage. I'm certain someone smarter and less lazy than me can calculate the amount of expected cycles that the battery would have seen.

Do you leave it fully charged for long periods of time, or do you discharge it down to empty or nearly empty quite regularly?

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

#205

Post by cogman10 »

beAbU wrote: post #204
cogman10 wrote: post #197

Earlier quoted context omitted.

270,000 km. And fast charging about 3 times a year. If I were to guess, the main factor harming the battery is my garage gets pretty hot in the summer (37 or 38C)

That is quite high mileage. I'm certain someone smarter and less lazy than me can calculate the amount of expected cycles that the battery would have seen. Do you leave it fully charged for long periods of time, or do you discharge it down to empty or nearly empty quite regularly?

I charge it to 70% and leave it there most of the time.

I don't often fully discharge, that's bad for the lipos. I usually keep a 40-70 range SOC.

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

#206

Post by DanielHB »

Xemplolo wrote: post #186
Lucian6 wrote: post #66

[dead]

How can this be a real issue? We don't have a lot of car makers and we do not have a huge amount of EV models. Either you are doing this on small scale, than you can select one or two specific EV models and use these batterie packs or you do it in big scale, than you can also easily adapt the most x batterie packs and only use these across your system. If you go down to the cell level, its more effort true but then y…

You can't really mix different types of cells together in the same pack. Even cells with the same manufacturer and chemistry can be problematic to mix if they are at different wear levels (or even from different batches from the same factory).

This is only practical if you reuse the whole pack, or at least the modules. And for that to work well you also need a lot of complex software to keep the packs working well with each other (like balancing power levels between the packs).

BMS software is no joke, it is already hard and complex enough when using brand new battery packs and cells of the same chemistry and manufacturer and wear level. Any kind of mixing massively increases the complexity and safety concerns.

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

#207

Post by bluGill »

jbm wrote: post #160
wcfields wrote: post #37

Earlier quoted context omitted.

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.

Is there any value in fixing the battery on these? IE: Do the other components last long enough to be worth the cost? It seems like procuring the battery is not as expensive as the Tesla battery (I see someone who did it themselves for $6k on Youtube with the battery from a wrecked leaf). In comparison, the cost I see for my Model 3 is about ~$18k CAD. Getting a car up and running for $8k might be worth it if it is o…

Is it worth spending money on a car that old? You are putting more than the car is worth into fixing it and you won't get that back if you sell. You also have no idea when/if something else will go. thew worst case is the day after you fix it someone hits you and the repairs will be $30,000 - what it cost new and there are still a lot of worn out parts: insurance will give you $4000 and tell you to eat the loss.

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

#208

Post by eldaisfish »

Dylan16807 wrote: post #74
irons wrote: post #44

Earlier quoted context omitted.

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.

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.

the average hides a lot of information. the largest peak load is often an electric stove, which is regularly greater than 1,500 kW.

Also, this idea that higher usage overlap with the sun being out is laughably wrong. Solar noon is between 11 AM and 2 PM. Very few people are home at that time. There is a reason that peak grid demand in almost every country is in the early evening.

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

#209

Post by 1234letshaveatw »

cowsandmilk wrote: post #194
jack_pp wrote: post #177

Earlier quoted context omitted.

Idk enough but I assume there are good reasons, however when a website is biased and finds even bad reasons to hate that's still a problem right?

What are the bad reasons that bias electrek’s coverage?

extremist "journalists" and/or undisclosed sponsorship? Contrast their Tesla coverage with their almost giddy stories on anything China related.

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

#210

Post by bluGill »

alvah wrote: post #134
pfdietz wrote: post #49

Earlier quoted context omitted.

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…

Is it worth using heat pumps in this setup (in addition to resistive elements)? I understand they can't reach the absolute temperature of resistive heating, but from an efficiency POV for the first few tens of degrees they are much more efficient.

Depends - the problem with heat pumps is when you need them the most they don't work. If it never gets below -10c (exact temperature needs more study, could be as low as -25) where you live they are fine - but that implies you live in an area where you don't get many cold days and so the expense isn't worth it (it also implies you live where it gets hot in sumner so you want ac anyway and the marginal additional cost makes it worth it again). If you live in an area where it gets colder you need additonal backup heat that can cover those really cold days and so you may as well run that system only.
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