Abstract: Dr. Su Min, director of the battery cell material research and development department of Wanxiang 123 Co., Ltd., said that China's solid-state battery-related patents and corresponding articles have accounted for more than 35%, which makes China's patent articles occupy the first place in the world, and China's solid-state battery development has entered a hot stage, and scientific problems and industrial problems go hand in hand.
The site of the 2024 Solid-State Battery Industry Ecosystem Entrepreneur Summit
Battery 100 - Battery Network, June 28 (Evergreen Lin Yin, Suzhou, Jiangsu, Graphic and Text Live) On June 28, the solid-state battery industry event - 2024 Solid-state Battery Industry Ecosystem Entrepreneur Summit was held in Xiangcheng, Suzhou. The forum was hosted by Zhongguancun New Battery Technology Innovation Alliance, Battery 100 Association, and the New Energy Special Committee of Suzhou New Era Business Administration Entrepreneurs Federation.
Su Min, director of the R&D department of battery cell materials of Wanxiang 123 Co., Ltd., and doctor
On the afternoon of the 28th, Dr. Su Min, director of the battery cell material R&D department of Wanxiang 123 Co., Ltd., gave a keynote speech entitled "Solid-state battery research status and development trend" at the forum, sharing the current situation, problems and challenges of the solid-state battery industry.
"The development of solid-state batteries has entered a red-hot stage, and scientific issues and industrial issues go hand in hand." Su Min preached.
According to the data, Wanxiang 123 was established in 2011, with decades of industry accumulation, and its products are mainly low-voltage energy-saving batteries, high-voltage power batteries and energy storage systems, which have been in the forefront of the world in the low-voltage field.
Su Min pointed out that the traditional liquid battery is facing a very big safety hazard, and how to achieve a safe and high energy density battery technology is also the goal that experts and colleagues in the industry are working towards.
According to the different electrolyte content, lithium batteries are generally divided into liquid batteries, semi-solid-state batteries and all-solid-state batteries, the safety of general liquid batteries is still okay at less than 270Wh/kg, for semi-solid-state batteries through the modification of electrolytes and positive and negative electrodes, separators can also achieve a certain degree of safety at an energy density of 300-400Wh/kg, for 400Wh/kg or even higher energy density, especially at a higher density the introduction of lithium metal anode, All-solid-state batteries are the best choice.
Su Min emphasized that both semi-solid and all-solid state have their most suitable energy density, and there is no one type of technology that is the only optimal solution, and it is a different battery safety technology under different densities of power batteries.
In addition, for all-solid-state batteries, Su Min said that in fact, its safety is the highest. All-solid-state batteries are divided into three categories according to the type of solid-state electrolyte: polymers, oxides, and sulfides. Among them, sulfide batteries are considered by the industry to be an effective technical means to achieve ultimate safety, but they also face many problems. Its advantage is that among the three electrolytes, the ionic conductivity is the highest, in addition to its disadvantages, it is also more obvious, the cost is higher, and the air stability is also poor. Although sulfide batteries are intrinsically safe, they bring higher challenges to personnel in the battery preparation process, especially once the silicon-based electrolyte fails and hydrogen sulfide is released during the preparation process, it will bring safety problems to operators.
On the other hand, oxides and sulfides are inorganic solid-state electrolytes that behave in batteries, especially from the point of view of lithium transport, as rigid punctate contacts. When the battery swells or pulverizes during the cycle, especially on the negative side, and the cracking of particles on the positive side, it will affect the transmission of lithium ions, block or change its transmission path, thereby affecting the life of the entire battery and greatly reducing the process performance of the battery.
In addition to all-solid-state batteries, Su Min also introduced polymer solid-state batteries, which have a certain elasticity and have good interface contact with the positive and negative electrodes. At present, the industry is using organic-inorganic composite technology, which combines inorganic solid electrolyte and organic solid electrolyte to achieve the effect of 1+1>2.
In addition, judging from the patents and published articles of solid-state batteries, LG Energy Solution and Toyota Motor have a great advantage in the number of patents at the company level. Not only are there some companies applying for patents in China, but universities and research institutes have also published a large number of patents, which means that China's solid-state battery technology has moved from the laboratory to the transformation of industrialization. Returning to the national level as a whole, China's solid-state battery-related patents and corresponding articles currently account for more than 35%, which makes China's patent articles occupy the first place in the world.
From the perspective of the entire loading process, the loading process of semi-solid-state batteries is much greater than that of all-solid-state batteries. In terms of semi-solid-state batteries, Dongfeng E70 has begun demonstration operation in 2022, and NIO and SAIC will also launch semi-solid-state battery vehicles in 2023 and 2024. Su Min believes that in 2025, mass production will still be dominated by semi-solid-state batteries, and all-solid-state batteries will be in the process of industrialization preparation from 2025 to 2027, and a certain batch capacity will gradually be achieved from 2028 to 2030.
Su Min emphasized that in the past few years, it is really necessary for colleagues and experts from all walks of life to work together to solve the technical problems and industrialization problems of all-solid-state batteries.
According to reports, Wanxiang has been laying out solid-state battery technology for a long time, and the company has always adhered to the concept of "safety is the gold standard for testing a lithium battery", and has laid out three generations of solid-state batteries. The first and second generations are in-situ cured gel solid-state batteries, which have reached an energy density of 350Wh/kg and are ready for mass production.
Finally, Su Min concluded that safety is the gold standard for judging a battery product, whether it is semi-solid, quasi-solid-state or all-solid-state technology, it is a different technical means to solve the potential safety hazards of battery cells under high specific energy demand. The advantages and disadvantages of solid-state batteries are sharp and angular, and how to achieve them requires the joint efforts of the whole industry.
(The above views are based on the shorthand of the forum and have not been reviewed by the speakers themselves.) ）