• Hello ES! We could use some help to get us past the finish line on building the new knowledgebase for the forum.
    Can you donate? Please see our fundraising page. Thank you!

Thread for new battery breakthrough PR releases

JRP3 said:
They took the overheated cell and cycled it at 5C 50 times. It lost over half it's capacity but didn't catch fire. Still nothing about Wh/kg.

Click to expand...
Oh my, half the capacity at 50 cycles. That does not bode well for it being fully solid, unless the electrodes themselves are getting oxidized in air and that's what is causing the issue

Still betting it uses a semi-solid electrolyte with a very low vapour pressure solvent.
 
The loss of vacuum means the loss of atmospheric pressure keeping the layers in contact. Repeated cycling and some internal expansion because of it would suggest loss of contact and capacity, what you would expect from a SS cell, no? I found it interesting how the capacity loss basically flatlined after a while instead of continuing to drop off.
 
Hillhater said:
So far it would appear that the cells have failed to meet ANY of their claims !
High temp (100C) cycling,
11 C charge rate,
100,000 cycle life,
..and still no data to verify the 400Wh/kg claim ?
Click to expand...
They worded their claims very carefully though. No claims were made beyond…
  • That they can be charged at 11C…they can.
  • They can be run at 100°C...they can. Sure, it might be for one cycle but they never claimed otherwise.
The (inevitably) extremely specific cycle life testing will be an extrapolated value IMO as it can’t be confirmed for a bunch of years. The 400Wh/kg claim is easy and already reached by other cells.

Yea, it’s all marketing BS but they’re doing a hell of a job keeping these cells in the news as they work on cycle life testing and getting funding/contracts.
 
BatteryMooch said:
  • That they can be charged at 11C…they can.
  • They can be run at 100°C...they can. Sure, it might be for one cycle but they never claimed otherwise.
Click to expand...
But only with cooling, which they claimed was not needed, and by inference all those claims should be compatable.…
….otherwise all testing is worthless !
IE. : 11 C for 100,000 cycles
…..100 deg C continuous without cooling.
etc.
 
Hillhater said:
But only with cooling, which they claimed was not needed, and by inference all those claims should be compatable.…
….otherwise all testing is worthless !
IE. : 11 C for 100,000 cycles
…..100 deg C continuous without cooling.
etc.
Click to expand...
IIRC they said that no active cooling (fans, water loops, etc.) was needed…another carefully worded claim. 🙂
 
Though the Verge 5C demo used cooling fans. My take is they have an impressive cell which can do quite a bit but maybe not as much as the marketing hype. From what I've seen so far I'd be happy with the cell if it hits or gets close to the 400Wh/kg mark and does only 1,000 cycles if it's affordable. That would easily allow a 400-500 mile range road going EV with a 400-500,000 mile lifespan, not to mention lighter and/or longer range Ebikes and Eskateboards. Any cycle life beyond that is a bonus of course.
 
JRP3 said:
Though the Verge 5C demo used cooling fans.
Click to expand...
Yea, I think that will be the (very reasonable) approach to help extend cell life. DL might brag about the cell‘s ability to survive a lot of heat but I’m sure that any decent cycle life specs will limit the temps to significantly below the 100°C max survivable temp.

JRP3 said:
My take is they have an impressive cell which can do quite a bit but maybe not as much as the marketing hype.
Click to expand...
Agreed. Certainly not all of the claims all at once.
High temp or high current? Sure, but then limited cycles.
100k cycles? Sure, but only at 0.2C.

Pretty typical situation for any cell IMO.
 
100k cycles is not even useful. Maybe there are some niche applications that could profit from that, but for EV use, total capacity of the battery has to be high enough to allow it to drive a decent range without recharging, so reasonable capacities are between 10 and 100 kWh, which means such a battery would last more than 10 million kilometers.
 
JRP3 said:
Though the Verge 5C demo used cooling fans. My take is they have an impressive cell which can do quite a bit but maybe not as much as the marketing hype. From what I've seen so far I'd be happy with the cell if it hits or gets close to the 400Wh/kg mark and does only 1,000 cycles if it's affordable. That would easily allow a 400-500 mile range road going EV with a 400-500,000 mile lifespan, not to mention lighter and/or longer range Ebikes and Eskateboards. Any cycle life beyond that is a bonus of course.
Click to expand...
It's doing basically none of the things it was the most hyped for (or at least they havent shown those claims to be true). The most important part was being ready for high capacity production out of non rare earth materials while being cheap to produce and being competitive with/better than existing tech. Nobody(excluding maybe people here) cares about a cell that can charge pretty fast and is pretty energy dense. It seems likely that they just got a good lithium cell from a supplier.
 
Last edited:
adsc said:
100k cycles is not even useful. Maybe there are some niche applications that could profit from that, but for EV use, total capacity of the battery has to be high enough to allow it to drive a decent range without recharging, so reasonable capacities are between 10 and 100 kWh, which means such a battery would last more than 10 million kilometers.
Click to expand...
It would completely solve our battery degradation, production and mining problems.
 
adsc said:
100k cycles is not even useful. Maybe there are some niche applications that could profit from that, but for EV use, total capacity of the battery has to be high enough to allow it to drive a decent range without recharging, so reasonable capacities are between 10 and 100 kWh, which means such a battery would last more than 10 million kilometers.
Click to expand...
If we could agree on more universal battery sizes and shapes and stuff even if the battery outlives the car it could find life in another car. Or it could then find use in stationary applications. As another poster mentioned it would massively help the resource extraction problem. I would agree that it's probably the least useful cell feature to focus on currently, but I wouldn't call it niche or useless :)

Edit: It could also help with the charging problem too by making it far more affordable for a company to set up a battery swapping network. I think that one is more niche though.
 
Last edited:
Epithemeus said:
It could also help with the charging problem too by making it far more affordable for a company to set up a battery swapping network. I think that one is more niche though.
Click to expand...
The more range you have and the faster charging available the less need for swapping. Swapping is a dead end for EV's IMO.
 
Did you read my numbers? 27 years is nowhere near the secondary life application that you posted. A proposed 100k cycle life battery would still be 243 years away from its secondary life.
 
adsc said:
Did you read my numbers? 27 years is nowhere near the secondary life application that you posted. A proposed 100k cycle life battery would still be 243 years away from its secondary life.
Click to expand...
Which are you talking about, 10K cycles or 100K cycles?
 
adsc said:
100k cycles is not even useful. Maybe there are some niche applications that could profit from that, but for EV use, total capacity of the battery has to be high enough to allow it to drive a decent range without recharging, so reasonable capacities are between 10 and 100 kWh, which means such a battery would last more than 10 million kilometers.
Click to expand...
100k cycles can help make a real case for second-life use of EV packs that use such a cell. Knowing that a pack could still last many, many years in BESS applications after being removed from an EV. Companies want buffers, they don't want to be anywhere near ratings. And customers always feel More Number = More Better.

A crazy high cycle life can also enable the EV manufacturer to push the cells harder than any others, increasing performance, while still retaining a usably high cycle life that can work with a long warranty to generate sales.

If we can run those cells at, let’s say, 70°C and still get cycle life equal to or better than existing cells then we can shrink or even remove active cooling. That increase reliability, lowers costs, and shrinks the pack. Or we can add more cells to extend range.
 
JRP3 said:
Which are you talking about, 10K cycles or 100K cycles?
Click to expand...
A 100k cycle battery has still 90% of its first life when it has done a full cycle every day for 27 years. It will only go into secondary life after 100k cycles, which is 270 years.

And the arguments about buffers for marketing and reduced cycle count when cell is pushed harder are fine, but they are beyond the point. If the proclaimed 100k cycles are not at a useful charge/discharge rate, then it's just false advertising and the "real" cycle count is much lower. Otherwise you could claim that any battery has 100k cycle life if you charge/discharge it at 0.01C. Who is going to disprove you?
 
adsc said:
And the arguments about buffers for marketing and reduced cycle count when cell is pushed harder are fine, but they are beyond the point. If the proclaimed 100k cycles are not at a useful charge/discharge rate, then it's just false advertising and the "real" cycle count is much lower. Otherwise you could claim that any battery has 100k cycle life if you charge/discharge it at 0.01C. Who is going to disprove you?
Click to expand...
My mention of exploiting a 100k cycle life rating by pushing the cell’s performance (and accepting the resulting cycle life loss) was a completely different topic than what conditions we want the specs to be set under. I was only addressing the idea that a 100k life cell had no real world use.

I can understand frustration at not having cycle life set at a charge/discharge rate we feel is “real” but in my opinion it’s not false advertising. Ratings like this aren’t for the end user, it’s for the engineers choosing which cell to use. Sure, DL is posting this stuff publicly. But their target audience is the engineers advising company bigwigs and investors, not us.

A manufacturer can set cycle life count for any conditions they want but very often it’s at 0.2C and 1C as the industry standard. Power cells often spec life at much higher levels too and also cold temp cycle life specs.

As a data point...the industry standard discharge for capacity testing is 0.2C but this is only a useful rate for a very small number of users. But it offers an easily comparable starting point for choosing cells and manufacturers will always say to test any cells of interest in the particular application. They can‘t issue cycle life specs for all the possible customer usage profiles. Other specs are often set this way too.

If a bunch of companies want to claim 100k cycles at some crazy low charge/discharge rate that’s fine. It‘s easy to disprove all of them within a couple of months (maybe even beginning at a couple of weeks) when the capacity loss curve obviously droops much, much too much to support their claim. Cycling at a low rate only minimizes some of the degradation mechanisms going on in a cell.
 
Last edited:
You must log in or register to reply here.
Back
Top