Since Tesla first released the 4680 large cylindrical battery at its "Battery Day" in 2020, this revolutionary battery product has attracted global attention. However, although four years have passed, the road to mass production of this battery has not been smooth. Today, let's take a closer look at the technical advantages of the 4680 battery and the reasons why it has not been mass-produced.
1. What are the technical advantages
1. High energy density
The energy density of the 4680 battery is five times higher than that of the previous 2170 battery. This means that in the same volume, the 4680 battery can store more electricity, thereby significantly improving the range of electric vehicles.
2. Full-ear design
Traditional lithium batteries are usually equipped with ears to connect the battery cell and the external circuit. However, this design increases resistance and limits the efficiency of current flow. Tesla's 4680 battery uses a non-ear design, allowing current to be conducted directly from the current collector to the cover and shell, greatly reducing resistance, increasing charging speed, and improving heat dissipation.
3. Dry electrode manufacturing process
Traditional wet coating requires a lot of solvents, but Tesla innovatively adopts dry electrode manufacturing process to avoid the complexity and environmental pollution in this process. This not only simplifies the production process, but also greatly reduces costs.
4. CTC (Cell to Chassis) technology
CTC technology integrates the battery directly into the chassis, reducing the number of intermediate components, which not only saves space, but also reduces the weight of the vehicle body and improves the overall efficiency of the vehicle.
5. Improved thermal management system
By optimizing the internal structure design of the battery, such as surface irregular design, the 4680 battery can better manage heat and prevent overheating, thereby extending battery life and improving safety.
2. Why is there no large-scale mass production?
Although the 4680 battery has many technical advantages, its mass production process has encountered many difficulties:
1. Complex production process
The 4680 battery uses a new dry electrode manufacturing process, which is very different from the traditional wet process and has extremely high requirements for production equipment and technology. In the initial stage, the debugging and optimization of the production line took a lot of time and resources.
2. Yield rate problem
According to relevant reports, as of the end of 2022, the yield rate of Tesla's 4680 battery was only 92%, and in order to achieve cost reduction and put it into commercial application, the actual required yield rate must reach more than 95%. In order to improve the yield rate, Tesla has to continue to carry out technology research and development and process improvement.
3. Supply chain challenges
The production of 4680 batteries involves the application of a variety of new materials, such as high-nickel positive electrode materials and silicon-based negative electrode materials, which puts higher requirements on the supply of raw materials. In addition, the lack of a complete battery industry chain in the United States has put Tesla under great pressure in battery mass production and cost control.
4. Market demand fluctuations
With the rapid development of the new energy vehicle market, the demand for batteries from various manufacturers is also changing. Tesla not only has to meet the needs of its own models, but also has to deal with order pressure from other partners. Uncertainties in the market have also affected the mass production plan of 4680 batteries.
3. Mass production progress
Although Tesla first announced the 4680 battery in 2020 and planned to start mass production in 2023, the actual mass production progress has encountered certain challenges. However, with the advancement of technology and the optimization of production lines, the situation is changing.
Milestones: As of September 2024, Tesla has successfully produced the 100 millionth 4680 battery, and its Texas Super Factory has achieved large-scale production of 4680 batteries.
Capacity expansion: Tesla is also expanding its factory in Nevada, planning to increase the annual production capacity of 4680 batteries to 100GWh.
Partners: Other manufacturers such as Panasonic and LG Energy Solutions are also actively promoting the mass production plan of 4680 batteries, which is expected to reach the level of mass production in 2025.
Although Tesla's 4680 large cylindrical battery has encountered many challenges in the past four years, its technological innovation has undoubtedly brought new hope to the electric vehicle industry. At present, Tesla and its partners are working hard to overcome these obstacles and promote the early mass production of 4680 batteries. We look forward to this battery being widely used in the market in the near future and contributing to global green travel.