With the increasing global emphasis on clean energy and sustainable development, the demand for batteries with high energy density, high safety and long life in fields such as electric vehicles and energy storage systems has increased dramatically. Although traditional liquid lithium batteries have achieved great success in the past few decades, their inherent safety hazards and energy density bottlenecks are gradually emerging. Solid-state batteries, with their unique solid-state electrolyte structure and excellent performance characteristics, are regarded as the "holy grail" of next-generation lithium battery technology.

So what are the current technical routes for solid-state batteries? What are the difficulties in its large-scale commercialization? Once mass production, what impact will it have on the industry?

Technical routes: The three routes have their own advantages and disadvantages, and domestic companies bet on different routes

In terms of technical routes, it is understood that according to the different electrolytes, there are currently three main technical routes for solid-state batteries, namely polymers, sulfides and oxides. Among them, polymer electrolytes belong to organic electrolytes, while the latter two belong to inorganic electrolytes.

On the whole, Chinese companies mainly use the oxide route, Japanese and South Korean companies mostly use the sulfide solid electrolyte technology route, and European and American companies are more balanced in the choice of the three routes.

Each of the three technical routes has its own advantages and disadvantages, specifically: sulfide electrolyte has the highest conductivity and great potential. However, due to poor thermal stability, the preparation process is complex and costly. CATL is a representative of this line; Polymer electrolytes are easy to process, compatible with existing liquid electrolyte production equipment, processes, and low cost. However, its conductivity is low, its stability is poor, and its potential is limited. Compared with the other two types, oxide electrolytes have a conductivity between polymers and sulfides, and have both mechanical and electrochemical stability, as well as cost advantages.

Considering the preparation difficulty, cost and other factors, the industrial chain of oxide electrolyte has been basically mature. Start-ups have begun to enter the mass production stage, and representative battery companies include Weilan, Qingtao, Ganfeng Lithium Battery, etc. But as we all know, every new technology that moves from the lab to the market must first be scaled up and commercialized.

Commercialization: It is necessary to overcome the material barrier and the cost barrier

In order to achieve commercialization, solid-state batteries need to overcome the two major barriers of materials and cost.

Although solid-state batteries work on the same principle as liquid lithium batteries, the lithium ions in the positive electrode are de-intercalated from the active material during charging and migrate to the negative electrode through the solid electrolyte to complete the charging and discharging process. However, from liquid batteries to solid-state batteries, the electrolyte material will first change, and the process will also change.

According to the analysis of Guolian Securities, the development and application of solid-state battery technology will present cascade penetration in the form of "solid-state electrolyte - new anode - new cathode", and the core lies in the introduction of new material system.

Among them, the anode material will be upgraded from graphite to silicon-based anode, lithium-containing anode, and lithium metal anode; The cathode materials will be iteratively upgraded from high-nickel ternary to high-voltage high-nickel ternary and ultra-high nickel ternary, and then to new cathode materials such as spinel lithium nickel-manganese oxide and layered lithium-rich manganese-based; The diaphragm will be upgraded from a traditional diaphragm to an oxide-coated diaphragm, or even eventually eliminated.

Of course, in order to achieve commercial application of solid-state batteries, in addition to technical research and material performance improvement, the key is to reduce costs. First, the cost of raw materials, including solid-state electrolytes and higher theoretical capacity cathodes and cathodes, is higher. For example, lithium sulfide is 5 to 10 times more expensive than lithium carbonate. Secondly, solid-state batteries have extremely high requirements for the production environment and the purity of raw materials, which puts forward more stringent requirements for production processes and quality control, and the replacement rate of production equipment is also greater. In addition, the imperfection of the industrial chain will also push up costs.

It is understood that the current cost of solid-state batteries is 4-10 times higher than that of batteries of the same specification. This high cost is not only reflected in the material side, but also in the manufacturing process. An industry insider said that the current liquid battery construction cost of 1GWh requires an investment of 150 million yuan, while the production cost of solid-state batteries is significantly higher than this level.

Industry players: A number of companies have announced timetables, and they are still semi-solid-state batteries

Even though there are still difficulties in materials and costs, over the years, Chinese companies have been releasing news on the R&D results and mass production time of solid-state batteries, which has opened the commercialization competition that should have started in 2027 in advance.

In May, SAIC Motor announced that it had entered a 500-day countdown to the mass production of all-solid-state batteries, and all-solid-state batteries will be mass-produced in 2026, which has become the earliest timetable for mass production of solid-state batteries. As a battery leader, CATL's attitude towards the R&D progress of all-solid-state batteries has also changed from being tight-lipped to voluntarily revealing that "it will reach the level of small batch production by 2027". In addition, according to an exclusive report from Late, CATL has increased its R&D investment in all-solid-state batteries, expanding its all-solid-state battery R&D team to more than 1,000 people.

At the end of August, Penghui Energy, a non-leading battery company, released all-solid-state battery products, and a sentence of "major breakthrough in all-solid-state batteries" drove the stock price to harvest two "20cm daily limits" in a row; At the beginning of September, Weilan New Energy announced that "sulfide (all-solid-state) batteries will have sales this year", which made experts excited; In November, GAC Group said that the company has initially opened up the whole process manufacturing process of all-solid-state batteries, and it is expected to be installed in Haobo models in 2026. Changan Automobile expects that the company will achieve all-solid-state battery installation verification in 2027 and mass production and installation of all-solid-state batteries in 2030. On November 15, the State Intellectual Property Office disclosed that Huawei disclosed a patent for silicon-based anode materials, titled "Silicon-based Anode Materials and Their Preparation Methods, Batteries and Terminals". This patent mainly solves the problem of low battery cycle performance caused by excessive expansion effect of silicon-based materials, and improves the cycle stability of the anode.

However, judging from the specific products that have been released so far, the current so-called solid-state batteries are not real all-solid-state batteries. For example, the light-year solid-state battery released by SAIC Zhiji is actually a semi-solid-state battery with "10% soaking liquid added to the electrolyte".

Although there is only a one-word difference between "half" and "full", what is reflected behind it is not only the difference in product performance, but also the difficulty of commercial application. It should be noted that although the global solid-state battery research and development has formed a number of technical routes such as polymers, oxides, sulfides and halides, there is no technical route that is fully mature, and most of them are still in the research and development stage, and there are many challenges in materials, interfaces, and battery cells. For example, the chemical stability and air stability of sulfide electrolytes are very poor, and mass production is difficult; The volume of the silicon-carbon anode expands greatly, and the lithium anode is still immature.

Industry impact: The electrolyte and separator on the battery have the greatest impact, and new energy vehicle manufacturers are taking the lead

Whether it is semi-solid-state or all-solid-state, or what is the technical route, the consensus of the industry is that solid-state batteries will not only have a great impact on the battery industry but also on the new energy vehicle industry.

From the perspective of the impact of the battery industry, the four major materials of lithium battery (cathode, anode, separator, and electrolyte) are the largest increment of solid-state electrolyte. There is no difference between the working principle of solid-state batteries and mainstream liquid batteries, the main difference is that solid-state batteries mainly replace the electrolyte and separator of liquid batteries with solid-state electrolytes, but the current semi-solid-state batteries still have separators and a small amount of electrolyte (accounting for about 5-10%), and all-solid-state batteries are basically solid-state electrolytes, and the separator depends on the route to decide whether to replace them.

From the perspective of new energy vehicles, it is worth noting that there are two years that have been repeatedly mentioned in the development schedule of solid-state batteries, namely 2027 and 2030.

In 2027, it is the mass production and delivery time of all-solid-state batteries promised to the market by some companies. However, some people believe that the real commercialization of solid-state batteries may have to be postponed until 2030.

For example, Cao Dongqiang, chairman of Gridtek nickel and cobalt, believes that the solidification of power batteries is an inevitable trend, and the market is generally anchored to commercialize in 2027, but from the perspective of the industry, the feasibility of this time point is not very strong, and with the advancement of time and technology research and development, the certainty in 2030 is relatively high.

Whether it is automobiles or battery manufacturers, the reason for rushing to catch up may be to maintain the battery advantage of domestic new energy vehicles. According to public information, Toyota, according to its latest schedule, its solid-state batteries are expected to be mass-produced in 2027 or 2028.

Therefore, for domestic car manufacturers, if they can't launch mass-produced solid-state batteries before Toyota, then the relevant industry discourse may be greatly impacted by Toyota.

Conclusion: The direction has been set, but there is still work to be done

Finally, on the whole, although some people have different voices on the development of solid-state batteries, many industry insiders said that solid-state battery technology has not yet broken through, and the research and development of new battery materials is still a major pain point.

However, it is undeniable that all-solid-state batteries are recognized as one of the preferred solutions for next-generation batteries, and will also become the key commanding heights of the next-generation battery technology competition. It is believed that with the continuous maturity of technology in the future, the cost may gradually decrease, and solid-state batteries will also usher in a large area of "car" in the near future.

As for the concept of individual stocks, Caixin Securities pointed out that with the accelerated development of solid-state batteries, industry-related links are expected to benefit. In the battery sector, it is recommended to pay attention to the layout of solid-state battery companies CATL (300750), Jinlongyu (002882), Penghui Energy (300438), etc. In the solid-state electrolyte link, it is recommended to pay attention to Sanxiang New Materials (603663), Shanghai Xiba (6032000), etc.

Shanxi Securities key recommendation: CATL (300750). It is recommended to pay attention to: (1) battery manufacturers such as Penghui Energy (300438), Nandu Power (300068), Funeng Technology (688567), etc.; (2) Entrepreneurial companies with leading technological progress, such as Qingtao Energy, Weilan New Energy, etc.; (3) Core materials solid electrolyte, such as Sanxiang New Materials (603663), Ruitai New Materials (301238), etc. (4) New cathode and anode materials, such as Tailan New Energy, Huineng Technology (301046), Dangsheng Technology (300073), Xiangfenghua (300890), Guoxuan Hi-Tech (002074), Rongbai Technology (688005), etc. Lithium metal anode focuses on Ganfeng Lithium (002460) and Tianqi Lithium (002466).

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