Current market situation and outlook of lithium electric materials, how long will it take to achieve 500 WH / Kg

Thanks to the development of new energy vehicles, power batteries are in the wind of high-speed development, and the development of new energy vehicles has also put forward higher requirements for the performance of power batteries. The Action Plan for the Development of the Automobile Power Battery Industry is proposed in the "Action Plan for the Development of the Automobile Power Battery Industry". By 2020, The ratio of the new lithium-ion power battery monomer to energy is more than 300w/Kg. By 2025, the ratio of the power cell monomer to energy of the new system will reach 500w/Kg.

Under the dual drive of policy and market, power batteries must develop in the direction of high energy density, high cycle performance, and high safety performance. This requires research institutions and enterprises to make improvements in positive, negative, and electrolyte materials. Solid state batteries, Silicon negative electrode, high nickel ternary materials, and lithium-rich manganese positive poles are considered to be the mainstream technology routes developed by companies in recent years.

Lithium-rich manganese positive electrode: ideal material with low precious metal content

In 2025, the technical goal of the monomer battery is to achieve 400 Wh/kg of energy. The development of new, more efficient and energy-efficient positive polar materials to overcome and replace existing defective positive polar materials has become a hot research topic. Among the known positive electrode materials, the discharge capacity of lithium-rich manganese positive electrode materials is more than 250 mAN/g, which is almost twice the actual capacity of commercialized positive electrode materials. At the same time, this kind of material is dominated by cheaper manganese, and the precious metal content is small. Compared with the commonly used lithium cobalt acid and nickel cobalt manganese ternary positive electrode materials, it is not only low in cost but also safe. Therefore, lithium-rich manganese positive electrode materials are considered as ideal materials for the next generation of lithium-powered batteries.

How long will it take to achieve 500wh / Kg? Overview of the Development Trend of Lithium Battery Materials

Many companies, including Dangsheng Technology, Jiangte Electric, and AVIC Lithium, are stepping up research and development of lithium manganese base positive electrode materials. The Institute of Physics of the Chinese Academy of Sciences improved the voltage attenuation of the positive cycle of lithium-rich manganese and reached the target of voltage attenuation within 2 inches after 100 weeks, making significant progress. The team of Peking University developed for the first time a lithium-rich manganese base positive electrode with a capacity of 400mAh/g, which can achieve a goal of 400W/kg.

At present, the full application of lithium-rich manganese base positive electrode still has technical problems such as reducing the first irreversible capacity loss, improving the ratio performance and cycle life, and suppressing the voltage attenuation of the cycle process.

High nickel ternary material: 2018 is the first year of development

According to the starting point study, the output of 2018 nickel cobalt manganese will reach 47 GWh, which will increase by 32 degrees from last year, while the production of lithium cobalt acid will be only 19 GWh, which is only 5 degrees higher than last year. Due to the scarcity of cobalt and the continuous increase in cobalt prices, battery companies have actively promoted the high nickel content of ternary materials. By reducing the proportion of cobalt in batteries to reduce costs, the cobalt content of NCM811 is only 6.06.

Nickel-cobalt manganese material has high energy density, stable electrochemical performance, and has advantages such as high capacity and low cost. In the future, it will gradually replace lithium iron phosphate and ordinary ternary batteries. At present, companies such as Sheng Technology, Sugiyama, and Beiterui have already achieved the mass production conditions of NCM811, and 2018 is considered to be the first year of the development of high-nickel ternary materials.

Solid battery: solid material replacing diaphragm and electrolyte

All-solid batteries are recognized in the industry and academia as one of the mainstream directions for the next phase of battery development.

How long will it take to achieve 500wh / Kg? Overview of the Development Trend of Lithium Battery Materials

On the one hand, all-solid battery technology is the only way for batteries to miniaturize and thin film. The volume of the diaphragm and electrolyte together accounts for almost 40 inches of battery volume. If the diaphragm and electrolyte are replaced with solid materials, the distance between the positive and negative poles can be shortened to a few microns, and the battery thickness can be greatly reduced.

On the other hand, compared to general lithium batteries, the energy density of all-solid batteries has been greatly increased, reaching 300-400Wh / kg, while lithium-ion batteries are generally 100-220Wh / kg. The high safety is also one of the important driving factors for the development of all-solid batteries. From a safety point of view, traditional lithium battery electrolytes are organic liquids that oxidize and decompose to produce gases at high temperatures, which are prone to combustion and greatly increase Unsafe, If solid materials are used instead of electrolytes, the battery's safety performance will be greatly improved.

At present, the polymer solid-state battery developed by the Qingdao Energy Institute of the Chinese Academy of Sciences can reach a energy density of 300 Wh/kg. The inorganic solid-state lithium battery developed by the Ningbo Institute of Materials of the Chinese Academy of Sciences has an energy density of 240 Wh/kg. In addition, the agency is cooperating with the Lithium industry. Promote its industrialization, The product is planned for mass production in 2019. Within the industry, battery leaders including Toyota, Panasonic, Samsung, Mitsubishi, and Ningde have all invested in R&D and deployment of solid-state batteries.

Solid state batteries are undoubtedly one of the mainstream technology routes in the future, but there are still problems such as high costs, complex preparation processes, and insufficient technology. It is also urgent to solve the problems such as low multiplier performance, large internal resistance, large pressure drop when high multiplier discharge, and unrealistic charging. There is still a road to achieve large-scale commercialization.

Silicon-negative: Two or three years to go

Silicone-carbon material is currently the most commercialized high-energy density new negative electrode material. SPIR expects that the Silicon carbon material industry will begin to truly embark on the big stage of lithium battery negative electrode material in the second half of 2018, and it will also be in the next two to three years. Will usher in a big explosion, the industry has a bright future.

How long will it take to achieve 500wh / Kg? Overview of the Development Trend of Lithium Battery Materials

The ultra-high theoretical energy density of Silicon carbon composites can significantly increase the specific capacity of monomers. In addition, it has the advantages of low deembedding lithium voltage and environmental friendliness. It is considered to be an ideal negative electrode material for replacing graphite. With the development of new energy vehicles, higher requirements are put forward for the specific energy of power cells. In the future, graphite will gradually be replaced by Silicon negative electrode materials.

As of December 2017, the top 8 negative materials companies in China are basically increasing their capacity to expand their Silicon and carbon materials, and there are also a number of cross-industry new entrants involved in the layout of Silicon and carbon negative materials, and their new production capacity will be 2018-2019. Started production one after another. BYD, Ningde era, Guoxuan Gaoke, Beiterui, Shanshan shares, Lishen, Bic, Wanxiang, etc. have all started the layout of Silicon negative electrode materials.

Although there are still problems such as high cost, difficult technology and imperfect supporting industry, the prospect of large-scale application is still promising.

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