Cybertruck Battery Pack Structural Analysis

The Munro Live Youtube channel tore down a Cybertruck vehicle below are some insights and highlights for the vehicle’s battery pack.

The Cybertruck battery pack uses Tesla’s 2nd generation 4680 form factor cells and the battery pack also is a structural element of the vehicle. The seats are directly attached to the battery pack which makes it easier to assemble the vehicles and also minimizes the necessity of having another layer of sheet metal between the battery pack and the vehicle interior.

Disassembling the battery pack from the vehicle we get to see that the pack has a bottom sheet metal lid for covering purposes. In the picture shown below the battery pack is turned upside down to take off the lid. Being an offroad vehicle it is highly likely that the battery pack will be hit by debris and rocks and the bottom lid may get damaged, so having the lid separate seems like an obvious choice from a replacement perspective. There’s a single layer of 4680 cells which seems to be organized in a symmetrical module fashion.

The surface which is visible in the above picture is the bottom, negative side of the battery pack and the positive terminals of the cells are on the other side of it which has connections to the battery management system. There are vertical standoffs on which the lid that was previously removed is rested. There is a good ~32mm gap between the cell negative of the battery pack and the top lid in which during a thermal runaway event the bottom/negative terminals of the cells act as a pressure release mechanism, which breaks the green foam and the mica top which is placed between both so the gas can evacuate in the empty region.

For side impacts, the battery pack has crumple zones on both longitudinal sides of it. Which can absorb impact during the event of a side crash and the cells are kept safe from getting damaged.

From a ventilation and pressure equalization standpoint, there is a moisture membrane for equalizing pressure inside of the battery pack according to the changes in altitude surrounding the battery pack.

During thermal runaway events, the orange part which snap fits to the bottom lid with the black part is supposed to fall off through which the gases and the pressure inside the battery pack can vent out. There are total 4 of these assemblies in the battery pack for the 4 modules in it.

The added advantage of the black(spark arrestor) seems to be that it can capture the small particles that during a thermal runaway event can fly out with the gases at very high velocity due to pressure buildup in the pack.

Flood ports: If there’s a coolant leak in the battery pack, the coolant will collect at the bottommost part of the module where the flood ports are placed, the flood ports have a membrane inside of it which after absorbing the coolant becomes thicker which actuates the flood port and allows the coolant to get out of the vehicle.

Overall, The pack looks very robust from an offroad vehicle perspective and has plenty amount of structural strength to it. More details can be found out on the Munro Live youtube channel.

References

  1. Tesla Cybertruck Battery Pack: Our First Impressions Under the Lid (youtube.com), Munro Live

Leave a Comment