Tesla helps the large cylindrical battery return to the track The 46 series family "king style" first appeared?

Financial Associated Press (Beijing reporter Xu Hao) news, with Tesla's global sales surge, cylindrical batteries have once again become a hot technology in the industry discussion.

At the China Electric Vehicle 100 Forum held on March 27, the heads of a number of electric battery companies gave their own judgments on the development of large cylindrical batteries. "The large cylindrical battery has become the king of the industry and has begun to dawn." Liu Jincheng, chairman of Ewell Lithium Energy, said this.

Safe and economical into the keywords of large cylindrical batteries

According to the different packaging methods, power batteries can be divided into cylindrical, square and soft bags and other types. The so-called large cylindrical battery refers to a cylindrical battery with a diameter of 46 mm, and the volume and energy density are higher than those of small cylindrical batteries with a diameter of 18 and 21 mm. As a manufacturer of large cylindrical batteries, Ewell Lithium Energy, BAK Batteries and Panasonic Are optimistic about their future development.

"There is constant innovation in the structure of the single battery, mainly to reduce the weight of the accessory." Ouyang Minggao, vice chairman of the China Electric Vehicle 100 Association and academician of the Chinese Academy of Sciences, also highlighted, "Cylindrical batteries, represented by Tesla, from 18650 to 21700 to 4680, to increase the capacity of the single body and improve the specific energy." ”

Not only the individual capacity and specific energy, in Liu Jincheng's view. Large cylindrical ternary batteries have greater system safety and no thermal diffusion occurs. "Judging from the definition of market requirements, we feel that it (large cylindrical batteries) can be absolutely safe."

One of the indicators of "absolute safety" that Liu Jincheng refers to is the characteristics of stable structure and zero stress during the whole life cycle of a large cylinder. Square batteries and soft pack batteries, in the process of their life, will produce internal stress and expansion force due to expansion, and the internal structure of the battery will change accordingly. "[Square and soft pack batteries] actually become something different from the beginning of the battery to the end of its life. Only the cylindrical battery, as always, did not change at the beginning of battery use to the end. Liu Jincheng said, "Square shell batteries and soft pack batteries will also have customers in the market, and there will be certain growth opportunities, but from the mainstream point of view, large cylindrical batteries will be the mainstream route." ”

Similar to Liu Jincheng's view, Fan Wenguang, vice president of BAK Battery, also mentioned the safety of large cylindrical batteries. "In terms of product performance, cylindrical batteries are the safest of several mainstream forms at present, and the high safety limit allows it to support chemical systems with higher energy density." At the same time, the cylindrical cell cell is small in size, easy to thermal management, can flexibly use of special-shaped space, and highly standardized form is conducive to platformization and iteration. "Fan Wenguang told reporters that from the perspective of the difficulty of industrialization, the cylindrical battery has the longest history of development, the degree of standardization is high, and a relatively unified standard has been achieved in the industry." At the same time, the automation level of cylindrical battery production is also higher than that of several other batteries, which ensures the high efficiency and consistency of the cylindrical battery production. On the other hand, production costs are also reduced. ”

Under the Tesla effect, the 46 series battery may become mainstream

In fact, cylindrical batteries, which have so many distinct advantages, have been on the edge of the market until 2021. The data shows that in 2020, cylindrical batteries account for less than 10% of China's power battery loading; in the global market, cylindrical batteries are only 23%, significantly lower than square and soft bags. However, with the surge in Tesla's global sales, cylindrical batteries gradually regained some market share; and with the introduction of Tesla's 4680 batteries, cylindrical batteries became famous again.

As the main supplier of Tesla batteries, Panasonic President Yusuke Kuami once again stated at the 100-person forum that the 4680 battery will become the mainstream of future cylindrical batteries.

Fan Wenguang also mentioned the relationship between the 4680 large cylindrical battery and Tesla. "We are probably from the end of 2019, the beginning of 2020 to introduce a new generation of products to high-end core customers, in 2020 has been with many core customers to start research and development (large cylindrical batteries)." Fan Wenguang admitted to the Financial Associated Press reporter that after Tesla released the 4680 battery, the large cylindrical battery ushered in a wave of project outbreaks.

According to the judgment of BAK batteries combined with the customer needs and industry information it has received, by 2025, large cylindrical batteries will account for at least more than 30% of the share, that is, about 480GWh, which has exceeded the total demand for global power batteries in 2021. And Yiwei Lithium Energy, which is also optimistic about the development prospects of large cylindrical batteries, has made corresponding production capacity reserves. According to Liu Jincheng, Ewell Lithium Energy has planned a 200GWh production capacity including large cylindrical batteries and square batteries, which is expected to be completed in 2022.

From the product point of view, taking Fan Wenguang's BAK battery as an example, at present, several representative products of its 46 family of large cylindrical batteries range in height from 80-120mm, energy density from 275Wh/kg to 300Wh/kg, fast charging to 80% The fastest is 15 minutes, and the slowest is 20 minutes. In addition, in the product sequence of BAK batteries, there are also some specially oriented customized products, such as products that can be quickly charged to within 9 minutes. It is reported that the large cylindrical power battery of BAK full polar ear technology has entered the sample mass production stage.

However, in the current domestic square-dominated battery market, the production enterprises of large cylindrical batteries are also facing many challenges. "[Large cylindrical batteries] place higher technical requirements on every process, there are still very few equipment suppliers, and it is also a challenge for upstream material supply." Fan Wenguang said that in addition to the supply side, the challenge to the demand side of electric vehicle companies is mainly that the main engine factory, which has previously lacked the corresponding technical reserves of cylindrical batteries, should take a technical route including battery management as soon as possible, "for example, BMS should adapt to the chemical characteristics, thermal management, and safety design of the ternary plus silicon anode." ”