The best EV prismatic battery cells are Chinese

CATL battery cell overview

What I like the most about prismatic battery cells is that they are like LEGO bricks and make easier the task of building battery packs. For this reason they are perfect for DIY (Do it yourself) EV projects and for automakers that plan to effortlessly upgrade the battery packs of their electric cars.

However, the improvement of EV prismatic battery cells has been painfully slow when compared to cylindrical or pouch types.

The current development of EV prismatic battery cells is especially slow in Japanese companies, for this reason last year Volkswagen started replacing its main battery cell supplier, changing from Sanyo/Panasonic to Samsung SDI. This change of supplier made possible to upgrade the battery cell capacity from 25 to 37 Ah. Now the Chinese battery cell maker CATL wants to do the same and replace Samsung SDI as the main battery cell supplier of Volkswagen and BMW.


Let’s see what CATL has already available and what’s reserved for the future.


CATL battery cell development roadmap


Below you can see the cycle life of the CATL 50 Ah battery cell that is being sold by Evlithium for 50 USD.


CATL 50 Ah NCM battery cell cycle life


Moving on, let’s see the application of these battery cells on some popular plug-in cars that already use standardized automotive prismatic battery cells.


Toyota Prius PHV (PHEV2 battery cells)

  • Battery with Sanyo 25 Ah cells: 95 x 3,7 V x 25 Ah = 8,79 kWh
  • Battery with CATL 50 Ah cells: 95 x 3,7 V x 50 Ah = 17,58 kWh


Unfortunately Toyota will never use Korean or Chinese battery cells. Japanese automakers only use battery cells from domestic companies… until Panasonic comes up with better prismatic battery cells, Toyota will ignore foreign alternatives and say that technology isn’t ready yet. Blind Japanese nationalism at its finest…


Volkswagen e-Golf (PHEV2 battery cells)

  • Battery with Samsung SDI 37 Ah cells: 264 x 3,7 V x 37 Ah = 36,14 kWh
  • Battery with CATL 50 Ah cells: 264 x 3,7 V x 50 Ah = 48,84 kWh
  • Battery with CATL 55 Ah cells: 264 x 3,7 V x 55 Ah = 53,72 kWh


Volkswagen e-up (PHEV2 battery cells)

  • Battery with Sanyo 25 Ah cells: 204 x 3,7 V x 25 Ah = 18,87 kWh
  • Battery with CATL 50 Ah cells: 204 x 3,7 V x 50 Ah = 37,74 kWh
  • Battery with CATL 55 Ah cells: 204 x 3,7 V x 55 Ah = 41,51 kWh


While now it seems unlikely that the e-Golf will have its battery upgraded before being replaced by the ID hatchback with MEB platform, the e-up is a good candidate for the upgrade…


BMW i3 (BEV2 battery cells)

  • Battery with Samsung SDI 94 Ah cells: 96 x 3,7 V x 94 Ah = 33,39 kWh
  • Battery with CATL 120 Ah cells: 96 x 3,7 V x 120 Ah = 42,62 kWh
  • Battery with CATL 160 Ah cells: 96 x 3,7 V x 160 Ah = 56,83 kWh


The BMW i3 with a 56,83 kWh battery and minor efficiency improvements would finally get an EPA range of 200 miles (322 km) or more.


It’s interesting that CATL seems to be ready to launch 160 Ah NCM 811 battery cells in the BEV2 VDA standard this year. Anyway, I don’t expect Samsung SDI to produce something similar before 2019. Remember that Samsung SDI will only move to NCM 622 this year – with the production of 50 Ah (PHEV2) and 120 Ah (BEV2) battery cells in its new plant in Hungary.

On average, the change from NCM 622 to 811 battery cells results in an energy density increase of roughly 30 percent.


To sum up, while CATL is still busy supplying the huge Chinese EV market with battery cells, the company is already trying to secure future supply deals with European automakers. Furthermore, Chinese battery cell makers are investing large sums of money in battery technology development and are hiring Korean battery experts.

The South Korean battery cell makers need to further improve their products if they want to keep their supply contracts…

Finally, I foresee Bosch teaming up with BASF to produce top-notch quality battery cells in Europe in a year or two. But will it be too late? At the moment the Korean and Chinese battery cell makers have a comfortable head start.



More info:

Pedro Lima

My interest in electric transportation is mostly political. I’m tired of coups and wars for oil. My expectation is that the adoption of electric transportation will be a factor for peace and democracy all over the world.

30 Responses

  1. Yogurt says:

    Great stuff…
    Who does CATL have contracts with now?
    Is BAIC one of them out of curiosity since they seem to be replacing BYD as the top BEV company over there…

    • Pedro Lima says:

      “Although the company has a history of only 6 years, it has formed long-term strategic cooperation relationships with many Chinese carmakers such as SAIC, BAIC, Geely, Dongfeng and Changan. What’s more, CATL managed to gain access to the supply chain of global carmakers, like BMW and VW.”

      The transition from LiFePO4 to NCM hasn’t been easy for BYD. Luckily, they produce electric cars and buses, their batteries have always a place to go.

  2. Magnus H says:

    The formulas for 55Ah cells have a slight error.

  3. Mg says:

    30% increase from 622 to 811 is huge! Are You sure about the number? Some time ago i found a paper with side by side comparision of densities of different chemistries and increase there was like 5-6%. The paper was quite old( perhaps 2014 or 2015) so might have been outdated but it would be much off. Only problem is i can’t locate it now:) Perhaps 30% figure takes into account additional inprovements beside 811 composition, so capacity gain is actually combined?

    • Pedro Lima says:

      Yes, I’m sure about the 30 percent energy density increase.

      All the recent data reports point to this figure (more or less).

      200 Wh/kg -> 240-250 Wh/kg (20-25 % more)
      450 Wh/L -> 600-650 Wh/L (33-44 % more)

      Furthermore, there will be a second generation NCM 811 cells with additional improvements to push it to 300-450 Wh/kg and 1.000-1.200 Wh/L – with the introduction of lithium metal anodes. As SolidEnergy proposes to achieve.

      • Mg says:

        Well, since Nissan Leaf has about 192×0.45=86.4L worth of cells at 650Wh/L that would be over 56kwh. Depending on actual Leaf 2018 battery size(perhaps 38.4 kWh nominal) that would be 45% increase good for some 215-220miles (if Leaf EPA rating is circulated 150miles – we don’t know official data yet). That would allow to run two different batteries at same phisical size. And that would also explain Nissan wait for 2019 Leaf to achieve 200 miles trashold. At 1200Wh/L it would become 400 miles so perhaps Nissan is going to stay with 192 cells indefinitly.

  4. Rafael says:

    En el articulo de la propia Catl se contradicen en el grafico dice que en el 2o trimestre del 2019 tendran lista su batería de 300wh/kg sin embargo más abajo ponen fecha en 2020 ni ellos mismos se aclaran……

  5. Denis says:

    very good article, thanks a lot

    VW don’t upgrade the batterie cell of the e-golf to maintain the ICE golf sells. Because with 50 kWh capacity the real range will be over 300 km. The demands will be to high, they may think also that they are not yet ready to produce this amount of cars. Look at the ioniq, bolt and model 3, manufacturers are no capable to follow the demand.

    • John Doe says:

      The demand IS already too high for them to supply. That is why they are doubling the capacity.

      There is about 1 year waiting time to get a new E-Golf, and 8-9 month to get an E-UP in Norway at the moment. I don’t think VW cares about how many EVs they sell. They have a good mark up on EVs too. It is made in the same factory as a normal Golf, and are therefor benefitting on the high volume production.
      The selling price indicated good profit on the E-Golf.

      • Foersom says:

        “It is made in the same factory as a normal Golf”
        No, the E-Golf is made in a special factory in Dresden.

      • brako79 says:

        The E-golf is produced both in Wolfsburg and Dresden.

  6. ZenBit888 says:

    Great article. Wondering if anyone thinks CATL may be producing batteries for or in partnership with JB&ZJMY Holding Company, Inc. (ZJMY)?

    ZJMY is a holding company emerging out of China with over a dozen promising patents, developing “3.0” EV technology, and a plan for battery swapping stations that allow for 5 minute swaps. Seems they have partnerships or partial ownership with other large manufacturers like Long Star, Chery, etc…

  7. James says:

    Does anyone know which Chinese cars use the CATL 50Ah PHEV cells?
    I’d be very interested to look up the specs
    I thought most Chinese EVs still used LiFePO4

  8. Tobias says:

    Any idea how to upgrade your BMW i3 to 160 ah (have 60 ah at the moment) ?

    Prices total?
    Would BMW support service on the car after upgrade?

    • Pedro Lima says:

      The 160 Ah battery cells aren’t available yet.

      Your best option would be to sell your BMW i3 and buy a new one when BMW release the 120 Ah version later this year.

      • Tobias says:

        I was hoping one day to do the battery upgrade myself. BMW is not really interested in upgrading batteries. They want to sell new cars unfortunately. My car works perfect but apart from that I would like to have the longer ranger with 120/160 ah…

        • Lars says:

          Tobias: You can be 100% sure that your warranty with BMW would be void, they would never support or service anything that you did not pay them for and that would be the same thing for any other carmaker.
          You would need to find a company to do the upgrade for you, that is not something you can do yourself unless you really know what you are doing. We are talking about deadly voltages and currents that can be produced by multi kW EV battery pack.

  9. Peter C says:

    Does anyone make a prismatic cell with the same dimensions and final voltage as the LEV50 used in the iMiEV, with 50Ah capacity or more? I am wondering about the possibility of a seamless swap over of cells without having to do any changing of BMS or software or structural modifications.

    • Pedro Lima says:

      I think that you could use any VDA BEV2 battery cell as a direct replacement – the dimensions are pretty much the same.

      GS Yuasa LEV50/50N: 115 x 171 x 44 mm
      VDA BEV2: 115 x 173 x 45 mm

      Since the charge/discharge voltage curves shouldn’t be much different the BMS wouldn’t have any problem handling the new cells.

      However, the GOM (Guess-O-Meter) of your car could get confused with much higher battery capacity than what it’s programmed to expect. You would get a functional but a bit crazy electric car 🙂

      • Benjamin Nead says:

        As an i-MiEV owner, I had the same questions as Peter C. You confirmed what I assumed would be the correct answers. No hurries for me, since my stock pack is still hold a charge just fine, but this is on the mental back burner for 7 to 10 years from now. Who knows what sort of excellent batteries will be available then? In regards to the links in your post, Pedro, I couldn’t find a program that would open up the German battery size proposals document. Is there a web page or a PDF of this article?

        A few years ago, I witnessed an interesting battery retrofit of a 1999 Ford Ranger EV pickup truck (rare factory built electric) that had completely expired NiMH cells. After the initial unsuccessful attempt to get the old cells to hold a charge, they were swapped out for LiFePO4 ones of similar physical size. The “head scratching” part of the retrofit was to electronically accommodate cells with not only larger capacities, but of higher voltages. The eventual cure was to solder together a custom circuit board that “tricked” the Ranger’s old computer into thinking the pack had the stock voltage and amperage specifications. The truck’s battery retro, by the way, was a complete success. The last time I talked to the owner, he was typically getting 100 miles per charge.

  10. Benjamin Nead says:

    Thanks, Pedro. That link works.

  11. Ralf K. says:

    As you can see, CATLs ATL-J1 (T = german “Tiefe” = english “depth” = 47.5mm) are slightly thicker than VDA BEV2 (45 mm). This will not make these CATL 120Ah or 160 Ah cells a direct drop-in replacement in those battery cases, where cells are already tightly packed (BMW i3, Fiat 500e). Standards are only good as long as manufacturers strictly adhere to them. Pedro, you should therefore reconsider if your scenarios of BMW i3 and Fiat 500e with “swapped cells” truely make sense.

    Apart from this aspect: a great analysis!

    I was surprised, that “ISS-LV” (idle stop start – low voltage) has its own VDA standard cell dimensions now (150 mm x 150 mm x 15 mm). While you focus on BEV/PHEV on, this could make 48V-mildhybrid applications cheaper for traditional ICE cars. With 20Ah in a 12s or 13s application, this would mean about a 1 kWh battery pack. I do believe these cells are the basis of Mercedes EQ Boost 48V batteries (new C class, E class, S class) in their mild-hybrid applications. This presentation in Sindelfinden may have persuaded Daimler:

    Also: the increase in VDA HEV size cells (6Ah=> 10Ah) is an improvement for many current hybrid car owners, where cars already use these VDA HEV sze cells.

    • antrik says:

      It’s not just a slight depth increase: according to this table, the ATL-J1 batteries are quite a bit higher than VDA-BEV2 (126 vs. 115 mm) — so clearly not a drop-in replacement at all; and makes the 120 Ah / 160 Ah claims considerably less impressive.

  12. infiniti3d says:

    Just curious how to connect these individual cells? The VW e-up Sanyo cells have a thread and nut style to connect them in serie and parallel, easy to assemble. This CatL come flat and they need a industrial laserwelder to pair them. This is not for DIY projects or is there a easier way to make the connection?

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