Continued: Tesla 4680 Battery-Battery Technology Upgrade-Part 3.
2.1.4. Opportunities Brought by All Tabs
From the previous pulse laser spot welding of the 2170 battery to the current 4680 battery line or laser lattice, the laser welding process is improved, and the original pulse laser may be changed to a continuous laser, and the overall cost will increase.
Advantage of 4680 all tabs
2.2. Big battery
2.2.1. Performance
Compared with the previous 2170 battery, the diameter and height of the 4680 battery are improved. The diameter is changed from 27mm to 46mm, and the height is changed from 70mm to 80mm. The thickness of the battery cell is increased, the curvature is reduced, and the hollow part is larger.
All tabs of 4680 cell
2.2.2. Advantages of larger size
- Reduce battery cost: reduce the proportion of the shell in the unit battery capacity, and the number of structural parts and welding is also significantly reduced (the cost is 14% lower than that of the 2170 battery).
- Increasing capacity density: As the size of the battery increases, the number of batteries in the battery pack decreases, the proportion of metal casings decreases, the proportion of materials such as positive and negative electrodes increases, and the energy density increases.
- The BMS system is more worry-free: the number of batteries in the battery pack is reduced, and the monitoring and status analysis of the batteries are simpler.
- Increased structural strength, perfect combination with CTC technology: 4680 has a larger size and higher structural strength. As a structural battery, it becomes a part of the car structure. It not only provides energy, but also serves as a support for the structure, saving space and reducing weight. (10%), thus increasing the cruising range (14%).
2.2.3. Disadvantages of larger size
Increasing heat generation: The larger the battery size, the more heat generated, and the more difficult it is to dissipate heat. Therefore, heat control is more difficult, and the greater the power generated by the battery explosion. This is the biggest bottleneck for the previous battery manufacturers to increase the battery size. Tesla uses all-tab technology. A breakthrough in thermal stability
……To be continued
