A picture has appeared on Twitter that reads “so this is Tesla’s 4680 pack, the next generation battery pack integrated into the structure of the vehicle that will change everything”. Although the picture is quite blurry, the design certainly looks interesting.
Let’s take a look at the following images in order, from Image 1 to Image 3. These are leaked photos from May of this year, previous spy shots leaked last year, and official concept images released by Tesla.
Note: There is only one picture and not much information available.
The latest May photo makes a few things clear:
1) Compared to the previous design of the Model 3, the new design has much smaller spacing between the battery cells. It appears to use a honeycomb-like structure and has alternating half-cell offsets, which is consistent with the concept image.
2) Based on the number of battery cells, the approximate number of cells is around 960 (24 cells per row, 10 rows per group, with 40 rows total). Assuming the 21700 cells have a capacity of 5Ah 1/3C, the 4680 cells would have 5 times the capacity, or 25Ah, for an estimated total of 87.6kWh.
3) From the spacing of the battery cells of the two rows, the cooling plate structure of the cells is still 2 rows per water spout. This structure seems to be cast together with the battery’s fixed structure. Based on this schematic, the cells are still fixed with adhesive.
4) This design is quite compact and there is no space for sampling lines or electrical design in the pack. It is likely that Tesla will still need to arrange the BMS and other components on top of the pack in the future. Therefore, Image 1 shows a plastic structure that extends upward. The degree of accuracy between Image 1 and Image 3 is not significantly different.5) From the perspective of the bus bar process, it seems that the new design has been changed from the Bonding direction, but it’s not very clear in this picture. The main body of the electrical connection is completed on the top.
6) Due to the high energy density design of the battery system, the battery tray is switched back to high-strength steel.
Conclusion
From the gradually released information, the completeness of Tesla’s 4680 battery pack is gradually improving. For Tesla, the challenges at the battery cell level may be greater than those of the CTC design.
This article is a translation by ChatGPT of a Chinese report from 42HOW. If you have any questions about it, please email bd@42how.com.