Redefining Energy Storage: The 4680 Battery Revolution

Unveiling the 4680 Battery: A Game-Changer in Energy Storage

At Tesla's Battery Day in September 2020, a revolutionary breakthrough was announced—the 4680 battery. But what exactly is the 4680 battery, and how does it differ from its predecessor, the 2170 battery? Let's dive into the details of this cutting-edge energy storage solution and explore the technological advancements that make it a game-changer in the automotive and energy industries.

 

The 4680 Battery: Redefining Performance and Efficiency

The 4680 battery, as the name suggests, features a diameter of 46mm and a height of 80mm. This larger form factor enables it to deliver remarkable improvements in cell capacity and power output compared to the 2170 battery. With a cell capacity five times larger than its predecessor, the 4680 battery enhances the range of Tesla's vehicles by an impressive 16% while delivering six times the power output of the 2170 battery.

 

Innovations in Design and Manufacturing

One of the key innovations of the 4680 battery is its full tab plus current collector plate structure, a departure from the single-tab design of the 2170 battery. This new configuration, which involves aligning the positive pole by perforating the bottom of the shell and sealing it with a cover plate using laser welding, represents a significant leap forward in battery design.

 

In terms of manufacturing processes, the 4680 battery introduces additional steps such as tab die cutting, rolling, and laser welding of the current collector plate and cover plate. Despite the increased complexity, Tesla has demonstrated impressive production capabilities, having already produced one million 4680 batteries in January, with an average yield rate of 92% and a peak yield rate of 97%.

 

Traditional vs. New Approach: Advantages and Challenges

The traditional approach to battery design involves the negative tab facing the bottom of the steel shell groove, while the positive tab is connected to the positive terminal using pulse laser penetration welding. While this approach offers space-saving advantages, it presents challenges when the battery wall thickness increases.

 

In contrast, the new approach adopted by the 4680 battery features a full tab structure with positive and negative current collector plates connected to both ends. This innovative design breaks the constraint that energy and power density cannot simultaneously increase, while also reducing the electron flow path and internal resistance.

 

Breaking the Constraints: The Full Tab Design Advantage

The introduction of the full tab design in the 4680 battery is a game-changer in energy storage technology. By reducing the electron flow path and internal resistance, this design significantly enhances the performance and efficiency of the battery. The traditional 2170 battery's electron flow path through the winding length of the current collector results in higher impedance, while the 4680 battery's full tab design reduces impedance and improves energy and power density.

 

Conclusion

In conclusion, the 4680 battery represents a monumental advancement in energy storage technology, redefining the performance, efficiency, and manufacturing capabilities of lithium-ion batteries. With its larger cell capacity, enhanced power output, and innovative design, the 4680 battery is poised to revolutionize the automotive and energy storage industries, driving forward the transition to sustainable and high-performance energy solutions.

 

By understanding the key innovations and advantages of the 4680 battery, we can appreciate its transformative potential and the pivotal role it plays in shaping the future of electric vehicles and renewable energy storage systems. As Tesla continues to push the boundaries of battery technology, the 4680 battery stands as a testament to the relentless pursuit of innovation and excellence in energy storage.