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