Toyota Continues To Move Forward With Solid State Battery Developments


Representatives from Toyota (including H. Iba from the Battery Research Division of Toyota Motor Corporation) recently participated in 17th International Meeting on Lithium Batteries in Como, Italy from June 10 to 14, 2014.

In their article “Invited Presentation: Innovative Batteries for Sustainable Mobility,” the Japanese company stated that it is developing new batteries with higher densities – solid state and lithium-air to be more accurate.

“And now, we are going to develop next-generation vehicles with more energy efficiency; for this reason we need to develop innovative batteries with higher energy densities than traditional batteries.  Figure 1 represents a rough sketch of Ragone plots for traditional Ni-MH and Li-ion batteries together with next-generation batteries such as all-solid-state batteries and Li-air batteries.  Although we have already developed prototype cells of all-solid-state batteries and Li-air batteries with energy densities of 400 Wh/L and 1000 Wh/L, respectively, it is also true that there are still many issues to be overcome until their practical application.  In the presentation, we will overview our recent effort on developing innovative batteries.”

Rechargeable Lithium-ion Batteries (credit to AESC)

Rechargeable Lithium-ion Batteries (credit to AESC)

As it turns out. the Li-air battery prototypes, which have at least 15-20 years to commercialization, reach energy densities of 1000 Wh/L (yes, we know that they intentionally do not give numbers in kg/L). But more interesting is that solid state lithium batteries achieved 400 Wh/L in the prototype stage and could be commercialized in 6 years. Toyota shows on the graph that this is progress compared to lithium-ion batteries (without solid state electrolyte).

We applaud all developments, but this is pretty strange, because we thought that a level of 400 Wh/L is already behind us. Here is a graph from AESC, which is a joint venture between NEC and Nissan. Li-ions (high capacity cells) are rated from 300-400 Wh/L (not 50-300 Wh/L). And Panasonic’s 18650 cells, at least 5 years ago, had 620 Wh/L in production with 800 Wh/L scheduled for 2013.

This puts us in dismay!

However relying on such data explain to us why executives from Toyota do not hurry up with EVs. And finally, current lithium-ion batteries need higher energy density and lower price, not higher power density.

Maybe some of our readers will tell us what is going on with these numbers from Toyota.

Source: Invited Presentation: Innovative Batteries for Sustainable Mobility via Green Car Congress

Category: Battery TechToyota

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17 responses to "Toyota Continues To Move Forward With Solid State Battery Developments"
  1. David Murray says:

    Why does Toyota even bother.. I thought they believed the future was with Fool Cells?

    1. sven says:

      Fuel cells vehicles use batteries as a buffer, and now there are even plug-in fuel cell vehicles. I guess you could call them a ERFC: extended range fuel cell vehicle.

      1. Assaf says:

        That acronym sounds like an invitation for parody…

        1. Mint says:

          If you’re a mathematician and ascribe to Elon’s description of them, there couldn’t be a better acronym.

  2. Nix says:

    Looks to me like a Toyota advertisement meant to convince their current Hybrid owners to buy yet one more Hybrid for their next car, while Toyota tells them to wait another decade before they buy an EV.

    1. pjwood says:

      And millions will listen.

  3. Josephus says:

    My guess is that high power density means quicker charge and discharge, which would be better in regenerative breaking. Surprisingly, I tend to agree with their model. Current Li-ion is fairly clunky, needs thermal management, and gets us between 70 and 250 miles/charge. We are all familiar with the space current technology needs for battery space in EVs. One day we will look back on Li-ion the way we do old projector tube TVs.

    That being said, until the market provides something better, give me Li-ion EVs all day.

  4. jmac says:

    David Murray said

    “Why does Toyota even bother.. I thought they believed the future was with Fool Cells?”

    That was also my first reaction when I read about Toyota’s battery adventures.

    The fact is that most major car companies have divisions within themselves that are exploring many power trains at the same time.

    There have pure battery electric engineers. But, there also engineers working on compressed natural gas vehicles.

    And yes, there are even engineers working on fool cells and still other engineers that work on hybrids.

    Separate engineering groups also work on plug-ins, on syandard ICE improvements, and so on.

    Obviously, most car companies are hedging their bets and have many irons in the fire at the same time.

    What is Toyota’s real strategy in all this ?

    I don’t know.

    One thing for sure, the hydrogen fuel cell is the dream fuel for the oil and other fossil fuel companies.

    It’s their “Ace -in-the-hole” since almost all hydrogen today comes from steam reformed natural gas and the other 5% comes from coal gasification.

    A fossil fuel company went to bed one night and had an incestuous wet dream. When they woke up, they called their dream “The Fuel Cell”

  5. Anthony says:

    Solid state batteries (SSB) currently have lower overall capacities than traditional Li-Ion cells. Toyota is trying to do the work necessary to being SSB up to the level of performance of current Li-Ion batteries, which it looks to accomplish by 2025. That’s a very conservative time frame. But honestly I don’t blame them. Back in 2008-2010 when everyone was high on batteries, companies made huge promises and set expectations high as to how much we could achieve on increasing cell performance and capacity – as the Panasonic link in the article shows their grandiose 4.0Ah cells set for 2013 never materialized.

    Well, 4 years later we know that batteries haven’t improved all that much since then. Tesla has been using the same capacity Panasonic cells in the Model S since the first delivery almost two years ago. The biggest improvement is the Kia Soul EV’s use of 200Wh/kg Li-Poly prismatic cells, and that’s very recent.

    Turns out, the goal hasn’t been on increasing capacity, its been on decreasing costs. Which is why, once the battery is at about 250Wh/kg, 750Wh/L and 500W/kg (Panasonic’s NCR18650B is close enough), the focus switches away from improving and getting to 400, 500 or 600Wh/kg to just figuring out how to make the things cheaper, and how to scale up production.

    Li-S cells (my expectation for next battery innovation) still wont be ready until 2016 at the very earliest, and likely need a few years to qualify by OEMs for larger vehicles, so you wont likely see those for generation 3 EVs (2020-2023).

    1. Nanda says:

      Your comment make sense

    2. JakeY says:

      “as the Panasonic link in the article shows their grandiose 4.0Ah cells set for 2013 never materialized.”
      It might be slightly delayed, but the 4.0Ah is set for release soon as the NCR18650C (rumors are it already released, but physical cells have not hit the market). Also the rumored that it will use a higher charging voltage, so part of the delay might be for addressing the originally promised low 3.4V nominal voltage (which reduced the cell’s energy density vs the 3.6V of Panasonic’s other cells).

      Also, Panasonic had already released their NCR18650G (3600mAh) last year.

      Back in 2008-2010, their flagship was the NCR18650A (3100mAh), so about 16% improvement with the 3600mAh. The Model S uses something similar to the 3400mAh NCR18650B which was released in 2012.

  6. jmac says:

    Okay, Toyota is testing batteries.

    The problem is that if you are going to test a battery to see if it can do 10,000 recharge cycles, then you must physically put the battery through 10,000 recharge cycles.

    This is a tremendously painstaking, time consuming process that inhibits new battery development and adoption.

    A number of groovy consumer electronics items are battery operated, like lap-tops.

    This kind of demand is the driving force for battery development quite apart from the relatively small demand for better electric car traction batteries.

    One of the issues that solid state batteries (including Toyota’s battery efforts) seeks to address is deterioration of the liquid/paste electrolytes through drying over time.

    While solid state batteries may address the longevity issue, the cost issue remains.

    Anthony has a good discussion of the dilemma.

    I think he is right. If electric cars are going to become affordable, then the batteries need to be cheaper.

    This certainly implies that mass production and economies of scale may be more important than than just battery advances alone.

    Advocates of electric cars have continuously said that most people only drive a few miles a day and that an electric car with 75-100 mile range is fine.

    Problem is ….. even vehicles like that are still far too expensive in comparison to petrol cars.

    1. Aaron says:

      That’s how Tesla and the Gigafactories will succeed — they will reduce the price of current-technology batteries to make EVs more affordable. Work on next-gen batteries can still continue, but they’re a solution for another day.

      1. TomArtm says:

        That is why Tesla is already succeeding – because their cars are already cost-competitive in their segments.

  7. Surya says:

    “we are going to develop next-generation vehicles”
    Not next-gen. Maybe the gen after the next one. Or the one after that one…

  8. shawn marshall says:

    ever wonder why car companies like to play it close to the vest? All the negative and wiseacre comments above may be an indication.

    1. Aaron says:

      Oh, you mean the realistic and fact-based comments? C’mon. You’re not even trying.