ssun30

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Exactly. SSBs in their current state are not usable for passenger vehicles at all.

If 250 kW / 441 kWh = the c rate,

then a car with a 250 kW (about 330 HP) motor and a 100 kWh battery will have a 2.5 c rate? That power is just like in a Tesla BEV.

You must have oversimplified your calculation of c rate or greatly understated it.
No you completely missed his point. He was saying the low C-rate is a major limitation with SSB.
 

internalaudit

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Exactly. SSBs in their current state are not usable for passenger vehicles at all.


No you completely missed his point. He was saying the low C-rate is a major limitation with SSB.

But he never explained how he got the low c rate. Or if he did (which he did), it didn't make sense if I had the wiggle room to provide my own calculation of a higher c rate.

He may be right though what Goodenough / Hydro Quebec / Daimler are working on affords a higher charge / discharge rate:

Rate characteristics and low-temperature operation
The two different proposed approaches were effective for reducing the internal resistance of the oxide ASSB. As we have already demonstrated very good cyclic stability of the ASSB at room temperature in our prior studies, there is no concern regarding the battery life41. Accordingly, we focused on the rate characteristics. Figure 7(a–d) shows the charge/discharge profile and the rate-dependence of the charge/discharge capacity at room temperature at various charging rates (from 0.2 C to 2 C) of Cell C used as a representative cell, as its internal resistance was successfully reduced. For comparison, the results for Cell A are also shown. With the decrease in internal resistance, a discharge capacity of 61 mAh/g was obtained at 2 C, which corresponds to 63% of the theoretical capacity of 97 mAh/g. Previously a sulphide-based ASSB using LiNi1/3Co1/3Mn1/3O2 as the cathode was evaluated at room temperature, and its capacity has been reported to be approximately one-third of the discharge capacity at 0.15 C12. Although the battery configuration of the sulphide-based ASSB is completely different from that of our cells, if this value is considered to be the benchmark, the rate characteristics of Cell C are satisfactory and promising. Thus, by increasing the area of the interface through the pulverisation of the cathode material, we succeeded in increasing the number of diffusion paths of the ions and electrons, thereby realising a large current charge/discharge. Furthermore, the diffusion distance within the active material was also shortened by the pulverisation of the cathode material, which might be the reason for the improved input/output characteristics.
 
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DFGeneer

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If 250 kW / 441 kWh = the c rate,
then a car with a 250 kW (about 330 HP) motor and a 100 kWh battery will have a 2.5 c rate? That power is just like in a Tesla BEV.



Yes, this is exactly how C-rate is defined:



He was saying the low C-rate is a major limitation with SSB.



Different solid state electrolytes have different ionic conductivities. Polymers (this Mercedes-Benz SSB) have lowest ionic conductivities of all, hence the low C-rates.
Other popular solid electrolytes are based on oxides, phophates and sulfides:
4248



In 2011 Toyota reported LGPS (sulphide) based SSB with ionic conductivity greater that liquid electrolytes:



In 2012 the TMG EV P002 prototype had 350kW motor and 42kWh lithium (I am guessing sulfide-based) ceramic battery. That's 8.3C (!). Granted, the longevity of this battery is unknown:
https://www.tgr-europe.com/en/servi...-p002-race-car-en/tmg-ev-p002-nuerburgring-en
 
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internalaudit

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What does it say, do you have access to it?
Murata have oxide-based SSBs as far as I know.

still sulfides I think:

TOKYO -- It was 1991 when Sony introduced the world to the first commercial lithium-ion battery, which would go on to revolutionize personal electronics.

Almost three decades on and it's time for a new battery technology as Japan's industry is being called on to build storage devices for electric vehicles as well as those needed to make renewable energy sources like the wind and sun dependable.

Sun and wind farms will never come into widespread use until the energy harvested from them can be efficiently stored. Efficient storage batteries will be needed by power plants, factories, homes, retail outlets and public facilities.

But Japanese battery makers are being swamped in the global market by Chinese and South Korean companies.

They are even under pressure to improve their game at home, where new Prime Minister Yoshihide Suga has pledged that Japan will achieve zero carbon emissions.

The global market for stationary storage batteries is forecast to double to nearly $23.9 billion in 2035 from where it was in 2019, according to research by Fuji Keizai Group.

Japan has staked out a position in the segment for electric vehicle batteries. But the biggest share of this submarket is held by Contemporary Amperex Technology, or CATL, a Chinese company founded in 2011 and backed by the Chinese government. It has expanded rapidly.

China plans to phase out new sales of all gasoline-powered vehicles, with the exception of hybrids, by 2035. As such, fast-growing companies like CATL, BYD and other Chinese battery makers are expected to gain even more momentum.

Meanwhile, South Korean companies are rapidly closing in on them.

Behind these global power, Japan is pinning its hopes on a new technology -- all solid-state batteries that use solid electrodes and a solid, instead of liquid, electrolyte that produces an electric current. The technology can produce long-life, heat-resistant batteries. It also lends itself to the making of small but large-capacity batteries and to high-speed charging.

An all-solid-state battery, experts say, allows an automobile to go 1,000 km on a single charge. That's enough for drivers to get from Tokyo to Fukuoka or from Bangkok to Ho Chi Minh City.

Japan remains the leader in solid-state batteries. Toyota Motor is accelerating a joint project with Panasonic to develop an in-vehicle solid-state battery before 2025. Murata Manufacturing is set to launch mass production of small batteries for cellphones and wearable devices before April.

Tall obstacles line the road ahead, though. While studies on sulfides for application to in-vehicle batteries are advancing, there is a possibility that sulfides generate gas when exposed to air.

That batteries might get wet is another problem. "Materials for all-solid-state batteries don't go well with water," a Toyota engineer said. "It is difficult to maintain a dry state in a plant and other facilities."

Murata is striving to further expand the capacity of its batteries and improve their charge-discharge efficiency.

To compete with China and South Korea, Japan needs to trim the weight of its storage batteries and give them more charging capacity.

"China has gotten ahead of us in the mass production of batteries," Japanese trade minister Hiroshi Kajiyama said, "but we still can catch up."
 

DFGeneer

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Thanks for the article.
No essential news though - the title hints on cooperation between Toyota and Murata, but this is not the case. They go with separate technologies and applications - Toyota (or rather Prime Planet Energy, their joint venture with Panasonic) with sulfides and automobiles and Murata with oxide-based electrolytes for consumer electronics.
Well, the wait continues...
 

internalaudit

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After cancelling my reservation for a TM3 in 2017 (for a few reasons including financial), I slowly began to realize the real Achilles heel of BEVs or even PHEVs will be the battery. This was the number one or two concern from other people too (who didn't want to adopt EVs) a few years ago but I didn't realize that the issue is real/

Coming from Honda's and Toyota's, whose upkeep are minimal outside of fuel costs, it doesn't make sense for owners who tend to buy cars and drive into the ground (I'm kinda like that) to pay a premium for a BEV upfront and then have to shell out more money for battery replacement say on the 10th year and beyond. It makes sense only to know the vehicle is zero emissions but of course my household's pocketbook is of utmost importance.

Majority of the Tesla Model S' are still under the unlimited mileage warranty as those that got theirs in 2012 were likely affiliated with the company. On Tesla Motor Clubc, there are already some complains from loyal owners about them getting the runaround from Tesla to get the battery replacement done. I think prior to 2017 or 18, Tesla did not guarantee a minimum capacity.

We are already starting to hear complaints about battery replacement costs, including on the 1st gen Leaf.

I think these things have to happen for more mass adoption of BEV:
  1. guaranteed ceiling cost for battery replacement (refurbished to order or made to order since stocking these don't make sense for dealers/manufacturers unless they do have lots of these refurbished units from replacements during the warranty period)
  2. battery warranty longer than 10 years (maybe 16 years to 50% capacity), even if only for the first owner
  3. Justified premium over comparable ICEVs or PHEVs - $15k premium for econobox cars is too much. $20-25k over barebone base models is probably okay for premium to entry-level luxury.
Beginning this year, Tesla dropped the Model S and X mileage warranty to 240,000 km. I thought it would bump it back up to unlimited mileage on Battery Day (the CEO is a master showman) but it didn't. Even the company knows warranty liabilities from these Li-ion batteries could be a nightmare, which is why the TM3 and Y batteries have close to bare minimum warranty, mandated by the US regulators (minimum akin to the emissions systems warranted for 8 years / 160,000 km).

Then I read that LFP is safer but LFP is just the cathode and it's still a Li-ion battery.

I don't mind going for a compelling BEV with Li-ion battery (rear wheel torque vectoring) but I'm not paying a big premium buying new and will wait for something use if at all. Hopefully by 2024/25, Honda and Toyota will have gotten economies of scale to justify selling more BEVs with better battery technology. If not, my CT200h, RAV4H and Accord hopefully will be chugging along fine still.
 

internalaudit

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CARB proposal. Definitely good news if passed as a regulation.


Because a long battery life is so important in realizing the environmental benefits of EVs, regulators are stepping in. Provisions for defining EV battery health are part of the Advanced Clean Cars II framework that the California Air Resources Board (CARB) presented for the first time earlier this month—a measure that aims to make EVs 80% of new light vehicle sales by 2035.



The rules, applying to the 2026 model year and beyond, would require that BEVs maintain 80% of their certified test-cycle range for 15 years or 150,000 miles, while fuel-cell models maintain at least 90% output power after 4,000 hours of operation.