Emerging Solid-State Battery Technology: Progress, Challenges, and Industry Misconceptions

With semi-solid state batteries gradually being integrated into vehicles, the full solid state battery is also on the horizon. This has generated significant attention in the industry, especially with remarks from SAIC Group President Jia Jianxu on April 10. He announced that SAIC’s next-generation solid state battery is set for mass production by the end of this year and will be utilized in the new MG4 model. Furthermore, SAIC’s first full solid state battery, named Light-Start Battery, is expected to launch in 2027.

The new battery boasts an energy density exceeding 400Wh/kg and a volumetric energy density surpassing 820Wh/L, with a battery capacity exceeding 75Ah. It has been tested under puncture and high-temperature conditions (up to 200°C), demonstrating that the cells do not ignite or explode, while maintaining a low-temperature capacity retention rate of over 90%. In the electric vehicle industry, full solid state batteries are viewed as a crucial breakthrough in battery technology and the ultimate battleground for competition. Many automakers anticipate that from 2027 to 2030, full solid state batteries will begin to be installed in small quantities, with widespread application expected after 2030.

According to Ouyang Minggao, Vice Chairman of the China Electric Vehicle 100 Forum and an academician at the Chinese Academy of Sciences, “The industrialization of full solid state batteries with an energy density of 400Wh/kg is projected for 2027-2028, with the potential for full-scale production around 2030. For 500Wh/kg vehicle solid state batteries, breakthroughs in lithium anode technology are necessary, which may require the assistance of AI-based material development platforms. The anticipated industrialization timeline is around 2030-2035, with a five-year uncertainty period.”

2025 is seen as a pivotal year for solid state batteries, often referred to as the “holy grail” of power batteries. Their primary advantage lies in replacing the traditional liquid electrolyte found in lithium batteries with a solid electrolyte, theoretically enabling higher energy density, longer driving ranges, faster charging speeds, and greater safety. Numerous automakers view 2025 as the target for the mass production of solid state batteries. For instance, Toyota plans to achieve small-scale production of solid state batteries by 2025, with stable mass production before 2030. Nissan aims to establish and operate a pilot production facility by 2025, with the first vehicle application expected in 2028. Volkswagen Group, in partnership with QuantumScape, also targets 2025 for solid state battery production, while Ford anticipates launching a model with solid state batteries in 2026. BYD is accelerating its solid state battery technology development and expects to achieve commercialization by 2026.

In January 2022, Dongfeng launched the world’s first solid state battery demonstration operation, and it has received approval for the first solid state battery passenger vehicle in China, with over 2.2 million kilometers demonstrated across ten cities in six provinces. Currently, Dongfeng has established a complete technology chain covering materials, cells, battery packs, and vehicles, achieving an energy density of 350Wh/kg for its solid state cells, with excellent low-temperature performance and leading product performance indicators domestically. The company is also accelerating the industrialization of 350Wh/kg solid state cells while concurrently developing 400Wh/kg cells.

Data shows that the penetration rate of semi-solid state batteries reached 22% in the first quarter of 2025, up from just 5% in 2023. Models that have already entered mass production with semi-solid state batteries include LanTu ZHUI GUANG, IM L6 Max, and NIO ET7, with plans for the MG4 and others to follow.

However, challenges remain for the commercialization of full solid state batteries. At the recent China Electric Vehicle 100 Forum, Zeng Yuqun, founder and chairman of CATL, criticized automakers for overstating the readiness of solid state batteries for mass production. He stated, “Claiming solid state batteries will be widely used by 2025 is irresponsible. It takes at least 8-10 years from lab samples to mass production. Most so-called ‘solid state batteries’ are actually semi-solid or quasi-solid, still containing a certain proportion of liquid electrolyte, which is fundamentally different from true full solid state batteries.” He emphasized that some automakers are misleading the public and investors about the maturity of solid state battery technology.

As the world’s largest power battery supplier, holding 37.4% of the global EV battery market in 2024, CATL’s technology choices are seen as indicators for the industry. Some industry insiders have questioned whether Zeng’s strong opposition to solid state batteries stems from CATL’s technological lag in this area. In response, Zeng stated, “CATL has invested over 10 years in solid state battery research and holds over 500 related patents. Our reluctance to casually commit to production timelines is due to our understanding of the challenges involved.”

The 2024 Global Solid State Battery Technology R&D Progress Report from the Chinese Academy of Sciences states that no true full solid state battery has achieved mass production globally. The report indicates that the most advanced quasi-solid state batteries still contain over 30% liquid components in their electrolytes, showing no significant advantages in key metrics like energy density and cycle life compared to traditional lithium batteries, while costing 2-3 times more.

Currently, challenges to the mass production and commercialization of full solid state batteries include an incomplete supply chain for raw materials and battery manufacturing equipment. There are critical issues to address, such as optimizing electrolyte materials, suppressing lithium dendrites, and ensuring proper contact at solid-solid interfaces. Additionally, many raw materials for solid state batteries have not yet achieved mass production, leaving the overall industry chain incomplete. Furthermore, as a new type of battery, solid state batteries require specific manufacturing equipment, necessitating substantial investment in research, development, and equipment upgrades. Due to these factors, the current cost of solid state batteries remains high.

In a statement, a Dongfeng representative noted, “Despite reports claiming liquid batteries have achieved 300Wh/kg energy density, full solid state batteries still possess irreplaceable advantages in further enhancing energy density, addressing safety risks, and improving adaptability to extreme environments. Currently, liquid batteries can only achieve incremental improvements through material micro-innovations, while full solid state batteries can achieve disruptive breakthroughs through system restructuring, making them a feasible option for exceeding 400Wh/kg energy density.”

As a result of the disruptive innovation in technology, full solid state batteries will face challenges related to raw material prices and technological maturity. Compared to the cost of liquid lithium batteries, they currently lack a price advantage. However, as the supply chain for key materials and manufacturing equipment for solid state batteries continues to improve, the prices may become comparable to those of liquid batteries. Thus, the future of full solid state batteries remains promising, particularly in the fields of power batteries, consumer batteries, and energy storage, with projections indicating that battery demand will exceed 1500GWh by 2030, providing a vast market for solid state batteries. Additionally, the industry anticipates small-scale applications of solid state batteries by 2026, with a significant production phase expected from 2027 to 2030.

Professor Huang Jia, Dean of the Materials Institute at Beijing Institute of Technology, commented, “Viewing full solid state batteries as the sole direction for battery technology development is one-sided. In the current context of large-scale electric vehicle adoption, a diversified technological approach is more beneficial for healthy industry development.” He noted that current lithium nickel cobalt manganese batteries and lithium iron phosphate batteries still have over 30% potential for performance improvement through material innovation and process optimization, which is sufficient to meet market demands for the next 5-8 years.

Looking at the technological landscape, the power battery industry is expected to exhibit a diversified and parallel development state. Liquid batteries will continue to optimize, such as doping lithium iron phosphate and the evolution of high-nickel ternary batteries toward ultra-high nickel variants, while full solid state batteries will accelerate commercialization. The competition within the industry ecosystem will intensify, with upstream resource competition heating up and breakthroughs in recycling technology becoming a significant competitive point. At the same time, downstream automakers will deepen collaborations with battery manufacturers while accelerating in-house research and development. Overall, the future of the power battery industry will trend toward a model of “technological diversity and ecological closure.”