Modern Panasonic prismatic battery cells
Panasonic is one of world’s biggest battery cell makers, but as strange as it may seem, the company is in a fragile position.
Supplying very energy-dense cylindrical NCA battery cells to Tesla has been the focus so far, however the company can’t be sustainable if it depends too much on a single customer, especially if this customer uses a type of cells that others don’t and even intents to produce its own cells someday.
Focused almost exclusively on Tesla and its cylindrical cells, Panasonic has been negligent with its own prismatic cells, which remained stagnant for years and led to losing extremely important customers like Volkswagen. However, now aiming to increase its customers list Panasonic recently improved its prismatic battery cells with a new chemistry.
In this article we’ll see how much did Panasonic’s prismatic battery cells for electric cars actually improved.
For electric vehicles Panasonic produces prismatic battery cells in PHEV2 form factor, which was introduced by VDA (German Association of the Automotive Industry) in an effort to standardize EV battery cells.
PHEV2 prismatic battery cell standard
- Length: 148 mm
- Height: 91 mm
- Thickness: 26,5 mm
Don’t let the name fool you, battery cells made in PHEV2 form can be used by BEV (Battery Electric Vehicle) and PHEV (Plug-in Hybrid Electric Vehicle) models. However, some cells can be optimized for energy density to use in BEVs, while others are optimized for power density to use in PHEVs.
Anyway, we will now compare the old with the new prismatic battery cell made by Panasonic for EVs.
Old cell (in use since 2013)
- Manufacturer: Sanyo/Panasonic
- Capacity: 25 Ah
- Nominal voltage: 3,667 V
- Energy: 91,675 Wh
- Form factor: PHEV2
- Chemistry: NCM/LMO hybrid cathode
Sanyo 25 Ah battery cell
This cell was very used by Volkswagen for BEV and PHEV models. Back then, Volkswagen’s strategy was to use the same battery cell in every electric car to achieve economy of scale.
Toyota still uses this very old cell in the Toyota Prius PHEV that clearly needs an upgrade to the new cell.
Examples:
- Volkswagen e-Golf (old generation) with 264 cells (88s3p): 264 x 25 Ah x 3,667 V = 24,2 kWh
- Volkswagen e-up (old generation) with 204 cells (102s2p): 204 x 25 Ah x 3,667 V = 18,7 kWh
- Volkswagen Golf GTE (old generation) with 96 cells (96s1p): 96 x 25 Ah x 3,667 V = 8,8 kWh
- Audi A3 e-tron with 96 cells (96s1p): 96 x 25 Ah x 3,667 V = 8,8 kWh
- Toyota Prius PHEV with 96 cells (96s1p): 96 x 25 Ah x 3,667 V = 8,8 kWh
New cell (in use since 2020)
- Manufacturer: Panasonic
- Capacity: 51 Ah
- Nominal voltage: 3,7 V
- Energy: 188,7 Wh
- Form factor: PHEV2
- Chemistry: NCM 622
The new battery cell is currently used by Japanese automakers. Toyota seems to be following Volkswagen’s old strategy and will use the same battery cell for BEVs and PHEVs to achieve economy of scale.
Examples:
- Toyota C-HR EV with 288 cells (96s3p): 288 x 51 Ah x 3,7 V = 54,3 kWh
- Lexus UX 300e with 288 cells (96s3p): 288 x 51 Ah x 3,7 V = 54,3 kWh
- Toyota RAV4 PHEV with 96 cells (96s1p): 96 x 51 Ah x 3,7 V = 18,1 kWh
- Suzuki Across with 96 cells (96s1p): 96 x 51 Ah x 3,7 V = 18,1 kWh
The Lexus UX 300e comes with a 10-year or 1 million km battery warranty, which only says good things about this new prismatic battery cell from Panasonic.
Not surprisingly, the Honda e and Mazda CX-30 Electric also use this battery cell, I just don’t know if in a 94s2p (35,5 kWh) or 96s2p (36,2 kWh) configuration. Nonetheless, the official specs say 35,5 kWh.
Lexus UX 300e platform
With the new prismatic battery cell, Panasonic improved cost, longevity and energy-density.
Technically possible upgrades
With the new cell the following battery upgrades are technically possible:
- Volkswagen e-Golf with 49,8 kWh
- Volkswagen e-up with 38,5 kWh
- Volkswagen Golf GTE with 18,1 kWh
- Toyota Prius PHEV with 18,1 kWh
However, they are just possible for third-parties and at least for Volkswagen, won’t happen officially…
Volkswagen
In 2017 the Volkswagen e-Golf got 37 Ah battery cells from Samsung SDI, but will be soon discontinued and completely replaced by the ID.3 meaning no more battery upgrades.
The Volkswagen e-up already got a battery upgrade to 36,8 kWh recently, but with pouch cells made by LG Chem in Europe (Poland).
As for the Volkswagen Golf GTE it just got the 37 Ah battery cells from Samsung SDI made in Europe (Hungary). An upgrade to Panasonic’s new prismatic cells isn’t probable because the company doesn’t have a plant in Europe.
Toyota
The Toyota Prius PHEV with a 18,1 kWh battery would get its WLTP range increased from 45 to 92 km (28 to 57 miles). However, I think it would be more rational to use the new battery cell to make a simpler Toyota Prius EV instead, with a 40,7 kWh battery by using 216 cells (108s2p). It would be an opportunity for Toyota to surpass the Hyundai IONIQ Electric in range, efficiency, fast charging rate and battery warranty. Possible, but not likely…
Toyota will continue to say that current batteries aren’t still good enough to make decent electric cars, fortunately the automaker didn’t use the same excuse to delay the introduction of hybrids and had no problem in using nickel-metal hydride battery cells…
What are the best alternatives for this battery cell?
CATL battery cell development roadmap
By now, CATL seems to have already surpassed 70 Ah with NCM 811 battery cells in the PHEV2 form. These battery cells make technically possible to increase the battery capacity of the Toyota C-HR EV and Lexus UX 300e by 40 % from 54,3 to 74,6 kWh.
Summing up…
The new NCM 622 prismatic battery cell by Panasonic seems good, it combines decent energy density and cost with great longevity.
However, it should have come at least 2 or 3 years ago, for example LG Chem launched its first NCM 622 battery cells in late 2016 for the Renault ZOE. Now with more affordable and energy-dense alternatives offered by Korean and Chinese companies, Panasonic’s new prismatic cell will likely be considered only by Japanese automakers that prefer domestic suppliers.
Panasonic’s partnership with Tesla won’t last forever and the company needs to do more if it doesn’t want to end up depending exclusively on Japanese automakers, especially since they aren’t exactly excited about producing electric cars…
Like every other battery cell maker that aims for sustainability, Panasonic needs to localize production and open their own battery plants in North America and Europe. Moreover, Panasonic needs to choose at least one cobalt-free chemistry (LFP, LFMP or LNMO) and start producing battery cells compatible with CTP (cell-to-pack) battery packs soon.
so true
Cycle must be a concern in these cells?
Massive buffers?
Honda e supposedly only has 29kWh useable from its 35.5kWh and we know from VW and Toyota that the old cells had 6kWh useable from that 8.8kWh battery in PHEVs, new RAV4 supposed to be 14kWh useable out the 18kWh
20%+ buffer is larger than normal?
Hi Sean.
I haven’t seen any credible sources for the usable battery capacity yet. Some sources say 28,5 kWh while others say 32 kWh.
Hi Pedro
Bjorn Nyland on YouTube had one for 2 weeks he estimated around 28-29kWh useable
While I would prefer a variable buffer set by the driver, if the buffer is fixed I think that a large one by default is a good thing.
In my opinion every electric car should only charge to 70 % by default, with the option to reach a higher SOC (State of Charge) when the driver needs more range.
Volkswagen currently advises to charge the ID.3 regularly only to 70 %.
Current decent size (30+ kWh) packs in BEVs usually have a reserve capacity of between 5-6% (100 kWh Teslas) and 10% to 12%. Smaller pack BEVs get cycled more frequently, and DC charged at typically higher c-rates (e.g. 50 kW on a 24 kWh LEAF (2C) vs. 55 kW on a 60 kWh Bolt (0.9C), and therefore typically have relatively larger reserve 10-12%, or a bit more.
PHEVs often have a much larger reserve, because the pack is subjected to even higher C-rates under breaking, and is cycled more frequently (daily in some cases). The 2013 generation Volt had a huge reserve capacity of around 51% more than the usable (10.9 kWh usable, 16.5 kWh gross).
Check out Pedro’s article (“battery charging: full versus empty”) detailing the advantages of shallow depth of discharge (DoD) for battery longevity. If the Volt is only ever cycling its pack between 5% and 70% true state of charge, it can last over 5,000 cycles. Packs cycled between 10% and 90% may last 1,500 cycles (~acceptable for a large battery/longish range BEV, not great for a daily cycled PHEV).
HEVs have relatively tiny packs (1 to 2 kWh, e.g. 1.3 kWh in early Prius) with even larger reserve buffers, but typically they use high power cells which are designed not for energy density but for power density, and high C-rates (perhaps 40C to 50C in very short bursts of typically under 10 seconds). These batteries mainly function to capture short burst regen braking energy and help keep the ICE turned off in crawling traffic, and help during short burst hard acceleration, so high capacity/range is not a requirement per se. The chemistry in these power cells can often handle fuller DoD, but still benefit from a generous reserve buffer.
Thanks for insight. Maybe I missed it, but what is net capacity of UX300e? Also I saw UX300e has a 50 kW DCFC speed. Seems low considering this pack is actively cooled, no? Are there air cooled BEVs with 100 kW or 150 kW charging? I suspect there is an upper limit for DCFC speed when air cooling the pack.
The UX300e is likely just a Lexus badged and trimmed version of the Toyota C-HR EV, with the same 54,3 kWh (gross) pack *as Pedro clearly states in the article!*
It has below 50 kW charging not because that’s a sensible hard limit, but because Toyota want to maintain their delusion that fuel cells are the only way to recharge a vehicle in 20 minutes or less, justifying their almost 3 decades of wasted investments (and lack of real action).
LEAF 62 kWh has passive air cooling and a headline 100 kW charging power capability. Even Nissan say 45 minutes to 80% SOC (in ideal conditions). Since the usable is around 56 kWH, this means the average charging speed is at best 59 kW (if 0-80%) or 52 kWh (if 10-80%). Few owners have ever seen higher than 55 kW in practice.
What cooling is required (for high C-rates of charging) depends on cell chemistry. Realistically, most EVs with NCx chemistry certainly see battery health and longevity benefits from active pack cooling, especially liquid.
It’s possible that a future very efficient BEV with LFP cells, modest motor power and modest charging rates “could” get away with active chilled air cooling (with a powerful chiller), and still have long battery service life, as well as adequate (~30 min for onward 2 hours) mid-trip charging speed.
I understand the pack is 54.3 kWh gross, but was curious about the usable (net) capacity. Maybe assuming 3.5 miles/kWh and a range of 167 miles (my guess based on NEDC range), that equates to 47.7 kWh usable? Maybe it is lower so Toyota feels confident about the pack warranty.
I completely agree with you that Toyota “chooses not to plug in” in their EU marketing parlance and are dragging their feet with BEV technology. As evidenced by the RAV4 Prime PHEV, they are also dragging their feet on meeting the large demand of this decent PHEV (I see it as a “gateway drug” to BEV). I am happy that they are finally putting effort into engineering a large pack PHEV and a BEV so let’s hope this expertise only grows and maybe even produces a BEV for the USA (where I live).
I do hope LFP technology improves as you suggest as I believe it should help drop the purchase price of BEVs, which will help improve BEV adoption, even though total cost of ownership is already on par with ICE cars.
Hi, please do you know anyone who is a manufacturer of electric motors for the mentioned lexus ux300e? I’m quite interested. Thanks
The techically very similar Toyota CHR/Izoa in China is powered by a 150 kW motor from Aisin. I assume the Lexus will have the same.
Hi Pedro,
At first glance I saw nothing interesting on this Panasonic 51 Ah VDA-PHEV2 format, because this capacity is already available for years for BEV application (1C/1C). But only now did I realize that Toyota used them in PHEV application (2C/2C) and so this is complete different story. As you mentioned a 51 Ah PHEV, “High Power” cell should be followed by ca 70 Ah BEV “High Energy” density in the same format.
Actually SVOLT present on its website a 126 Ah BEV cells which is based on the VDA-PHEV2 format, only its twice as thick (52 mm instead of 27 mm).
Hi Pajda.
Indeed, this battery cell is very decent and if it was produced in Europe, some European automakers could have chosen it for their PHEVs. Instead they are using less energy dense battery cells produced by Samsung SDI in Hungary.
The Golf GTE battery was made by Panasonic (from what I’ve seen in this video: https://youtu.be/M0x3_XwCgJ0?t=139), so might it be carrying the new cell now?
Hi Neu7ral.
As I wrote in the article the old Volkswagen Golf GTE had a 8,8 kWh battery made with 25 Ah battery cells from Sanyo/Panasonic. This year the new version got a 13,1 kWh battery made with 37 Ah battery cells from Samsung SDI (made in Hungary).
Unfortunately Panasonic still doesn’t produce battery cells in Europe, that’s why Volkswagen chose Samsung SDI.
Pedro, are most BEV and PHEV packs constructed from cells manufactured near the pack assembly factory? I’m guessing this saves a lot of cost (and emissions, too).
Hi Barry.
Yes, that’s the reason why the big 3 Korean battery cell makers (LG Chem, Samsung SDI and SK Innovation) already opened plants in China, North America and Europe.
Currently the PSA Group is importing CATL battery cells from China to make electric cars in Europe, but CATL will open its plant in Germany next year to reduce costs.
Thank you. So 24.2 kWh e-Golf cells were imported into Germany? Does Panasonic have plans for a cell factory in Europe?
Yes, those battery cells were imported from Japan.
Panasonic also produces prismatic battery cells in China since 2018. Europe would be the next logical step, but I haven’t read anything about it.
https://news.panasonic.com/global/press/data/2017/04/en170427-2/en170427-2.html
See whether this polymer battery has hopes.
https://www.bloombergquint.com/technology/nissan-pioneer-touts-resin-battery-that-s-90-cheaper-to-make
Looks interesting for a distant future. Thanks for sharing.
Name of these Panasonic cells: Panasonic UF261591TA
Safety sheet of UX300e battery pack: https://www.lexus-tech.eu/HYBRID/MSDS/EN/UX300e.pdf
interesting isnt it? Bottom of the line Tesla using its cylinder style battery is still more output than the best of the prismatic