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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?

#31

Post by torginus »

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).

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

#32

Post by trhway »

p0w3n3d wrote: post #18
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…

Tesla batteries fail after 8 years at least from models up to 2014

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.

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

#34

Post by bee_rider »

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

This is like a “fusion is only 20 years away” (or 15 in this case) joke, right?

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

#35

Post by dukeofdoom »

pinkgolem wrote: post #28
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…

i have heard that hybrid's have a maintanance problem? is not a concern, double the technologie in the same space?

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

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

#36

Post by jeffbee »

Rebelgecko wrote: post #17
pfdietz wrote: post #4

Earlier quoted context omitted.

So, basically the same reason recycling of PV modules hasn't taken off.

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?

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.

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

#37

Post by wcfields »

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…

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.

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

#39

Post by dukeofdoom »

pinkgolem wrote: post #28
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…

i have heard that hybrid's have a maintanance problem? is not a concern, double the technologie in the same space?

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" -

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

#40

Post by MrRadar »

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…

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

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