At present, new energy vehicle manufacturers all use artificial graphite as the anode material for lithium batteries, but the theoretical specific capacity of graphite anodes in lithium batteries is only 372mAh/g, and the actual specific capacity of commercial high-end graphite materials is 360-365mAh/g. Today, the energy density of lithium-ion batteries may have reached the limit. In the past 10 years, the ways for improvement of battery high energy density has been exhausted.
Thinning the substrate, increasing the compaction density, increasing the working voltage, and improving the first effect of graphite. But those means have boundaries, and now they've all reached their tops, and in this case, silicon is on the radar again. Silicon-based anode materials have become an ideal material breakthrough point for power battery upgrades with their gram capacity ten times that of graphite anodes and as high as 4200mAh/g.
In 2017, China's silicon-based anode material shipments were only 1,600 tons. In 2020, the shipments reached 6,000 tons. In the past 2021, the monthly shipments were close to 1,000 tons. In the context of the industry's increasing requirements for energy density, silicon-based anode materials have gradually become the focus of industry attention. Behind the rapid growth of silicon-based anode materials shipments, on the one hand, from the strong market demand for power tools and smart home lithium batteries.
In addition, the supply of lithium batteries such as international power tool giants and cross-border e-commerce companies has shifted to China, and the increase in demand for high-capacity and high-rate lithium batteries has driven the demand for silicon-based anodes in China. On the other hand, due to the steady growth of power batteries, especially the upcoming 4680 battery will become the driving force for the market. On April 8, 2022, after the opening event of the Texas Gigafactory Cyber Rodeo, Tesla officially delivered the first batch of Model Y production vehicles with 4680 batteries produced at the factory.
It is understood that each Model Y requires about 1,000 4680 batteries. In order to deliver the million-level car, Tesla is essential for outsourcing in addition to self-made batteries. In this context, the top lithium battery suppliers in China are accelerating the construction of 4680 battery production lines, and many manufacturers are following up, and large cylindrical battery will become the growth point of silicon-based anode.
Global silicon-based anode manufacturers mainly include Japan's SHOWA DENKO, Shin-Etsu Chemical, South Korea's Daejoo Electronic Materials, American Amprius, Group14, Sila Nano, Enevate, Canada's NEO Battery, Israel's StoreDot, etc. Japan's SHOWA DENKO acquired Hitachi Chemical, one of the "Hitachi Royal Three" in 2019, and merged its own silicon-based anode business to establish Showa Denko Materials Co., Ltd. The customers are mainly Japan's Panasonic and Tesla.
By controlling silicon particles and silicate nanoparticles uniformly in a three-dimensional nanostructure, Daeju obtained silicon composite oxides, which were then added to the existing carbon-based negative electrode materials (5~25wt%), greatly increasing the negative electrode capacity from 350mAh/g. Increased to 400~600mAh/g, the product brand is DMSO, including DMSO Hxx and DMSO HCE 8516 series.
American Amprius is famous for its 100% silicon nanowire technology. On January 18, 2022, Amprius (Nanjing) Co., Ltd. officially signed a contract and broke ground for the 20,000-ton new silicon anode material production base project in Lujiang High-tech Zone, Hefei, Anhui Province. The production base will be constructed in three phases with a total investment of about 2 billion yuan. The first phase of construction is expected to be completed and put into operation in the second half of 2022.
The flagship product of Group14 in the United States is the silicon-carbon composite anode material SCC55™, which will begin commercial production in April 2021. Currently, Group14 has a BAM factory in Washington with an annual output of 120 tons; it is planning to build another BAM factory in Washington. In addition, 1 BAM plant is planned in South Korea, which will produce 12,000 tons or more of SCC55™ per year in total.
The silicon anode material of Sila Nano in the United States is different from the well-known silicon-based battery in the market that replaces part of the graphite with silicon, and its target is an all-silicon anode material. Recently, Mercedes-Benz and Sila Nano have reached a cooperation. From 2025, Mercedes-Benz will be equipped with silicon-based anode high-energy density battery on its G-Class electric car, which will be supplied by CATL , and the anode material supplier is Sila Nano.
NEO Battery of Canada focuses on the development of NBMSiDE, a silicon anode material for lithium-ion batteries for electric vehicles, through a proprietary nano-coating. In 2021, NEO will launch three variants of NBMSiDE-P100, NBMSiDE-P200 and NBMSiDE-C100, and plans to achieve semi-commercial-scale production by the end of 2022, with a planned production capacity of 2,000 tons per year.
The "XFC-Flash Battery", a silicon-based anode battery designed by Israel's StoreDot, is known for its fast charging capability. The first development samples were shown to potential partners in early 2021, before a strategic framework agreement was signed with Chinese battery manufacturer EVE in May 2021 - with the goal of mass production by 2024. The companies in China that have truly achieved mass production and mass supply of silicon-based anodes only are Shanshan Corporation and BTR. Other companies are in the deployment, R&D, or pilot stage.
The existing production capacity of BTR's silicon-based negative electrode is full production and sales.A new 40,000-ton silicon-based anode material project will be built, and the first phase of 15,000 tons will be completed and put into operation by the end of December 2023. Shanshan Corporation has taken the lead in realizing mass supply, maintaining its leadership in the fast-charging consumer product market. The latest generation of fast charging products (3C, 5C) have been trial-produced in mainstream consumer companies around the world, and are expected to be fully introduced in 2022.
In the field of power battery applications, it has also passed multiple rounds of evaluations by mainstream car companies, and is expected to be shipped in batches next year. PUTAILAI has completed the research and development of the second-generation silicon carbon anode products, and has the conditions for industrialization. The planned production capacity is 1,000 tons, and mass production is expected by the end of 2022. In addition, a silicon oxide pilot line has been established in Liyang. The 1,000-ton silicon-based negative electrode of SH Phase I has entered the trial production stage and is expected to be shipped in batches in the second half of this year.
On May 5, the company announced that it plans to invest in the construction of a 30,000-ton/year silicon-based anode project. The project is expected to be put into operation in April 2024. In addition to the previously planned 20,000-ton silicon-based anode project, the company's silicon-based anode project will be fully operational. The anode production capacity will reach 50,000 tons/year. GUIBAO TECH's silicon carbon anode material has been evaluated by several battery manufacturers and has been supplied in small batches.
It has been recognized by some battery manufacturers and can be cooperated in large quantities in the future. The planned construction of 10,000 tons/year silicon carbon anode material project is undergoing relevant procedures, and the planned workshop is also under design. XFH has research and development in silicon carbon and silicon oxygen anodes. The silicon carbon anode material product is in the pilot stage and has the conditions for industrialization, the silicon-oxygen anode material is currently in the pilot stage.
3.Mass production bottleneck
For the moment, the mass production of silicon-based anodes still faces several bottlenecks: (1) The silicon-based negative electrode still has the problems of easy volume expansion of silicon, poor electrical conductivity, and large first-time charge-discharge loss; (2) Silicon-based anodes are still in the early stage of industrialization, with small production capacity, high prices, and lack of cost-effectiveness advantages; (3) The composite doping ratio of the silicon-based negative electrode is small, the incremental space is limited, and the process technology needs to be broken through.
4.Silicon-based anode materials may have large-scale production capacity release in 2023
In the past few years, policy subsidies have strongly supported high-energy density power batteries, and the silicon-based anode market has developed well. In the past two years, policy subsidies have fallen sharply, the upstream and downstream industries have reduced costs and market competition has become more fierce, and the market demand for silicon-based anodes with bright prospects has been sluggish.
Currently, silicon-based anodes are mainly used in consumer electronics, power tools and other fields, and the field of power batteries has more room for growth. In 2021, the global installed capacity of power batteries will be 296.8GWh, and according to the forecast of SNE Research, a Korean research institution, this data will reach 663GWh in 2023. Driven by the growth of the power battery market, especially the release of the 4680 battery as a large cylindrical battery, the demand for silicon-based anodes will further increase. It is expected that silicon-based anode materials will release large-scale production capacity in 2023.