As the year 2024 draws to a close, Huawei's recent announcement has sent ripples through the world of solid-state batteriesIn November, the company revealed a patent related to sulfide solid electrolyte materials and their manufacturing methods, which immediately garnered attention within the industryUpon closer inspection, it was discovered that this patent had been filed with relevant authorities back in May 2023, hinting at Huawei's deep involvement and stirring excitement across the sector.

Industry experts have noted that from 2023 to 2024, numerous companies within the global supply chain have been actively promoting their advances in solid-state battery technology, particularly among automobile manufacturersFor instance, in July of the previous year, Toyota boldly stated its ambition to achieve commercialization of all-solid-state battery technology by 2027 to 2028.

On the domestic front, companies like SAIC Motor Corporation and GAC Group have publicly announced their plans to achieve mass production of all-solid-state batteries by as early as 2026. Moreover, in March of this year, NIO unveiled its battery partnership with Weilan New Energy, introducing a 150kWh ultra-long battery pack that has officially entered mass production and is already being utilized since June, albeit under a leasing model rather than for direct sale.

Battery cell manufacturers such as Guoxuan High-Tech and Taian Blue New Energy have also demonstrated recent breakthroughs in the field of solid-state batteries

Despite the flurry of positive announcements, it is important to clarify that "implementation on vehicles" does not equate to "mass production." Furthermore, the distinctions between "semi-solid" and "solid-state" technology signify completely different concepts, making it essential to frame any announcements without a clear roadmap or timeline merely as aspirations or projected developments.

The hype surrounding solid-state battery concept stocks continues unabatedCurrently, there exists a "solid-state battery" concept stock list of around 50 companies within the A-share marketWhenever any firm announces news related to solid-state batteries, their stock prices tend to soarThis phenomenon has led to a pattern of companies leveraging these concepts to boost their stock values, casting a shadow over the actual progress of solid-state battery technology.

However, excitement based solely on anticipation can be misleading

• The AI Luminescence of a Spectral Chip
• Gold and Silver Soar to Expectations
• U.S. Stocks Fall After 25 Basis Point Rate Cut
• Gold, Silver Seen Rebounding After Dip
• Solid-State Battery Hype: Three Points for Consideration

Observers within the industry express skepticism regarding the timeline for breakthroughs in solid-state batteriesAs we approach 2024, they assert that substantial technological advancements remain elusive, indicating that the tipping point for mass production lies somewhere in the distant futureWithin this context, China's energy sector has proposed three key reflections amidst the current fervor for solid-state batteries:

First Reflection: CATL's Ambivalence and Conservatism

In contrast to the prevailing enthusiasm in the sector, where many are competing to attract investment and establish production lines for solid-state and semi-solid batteries, CATL (Contemporary Amperex Technology CoLimited) appears markedly cautious and ambiguous in its projections regarding solid-state battery technology.

During a car industry forum in July 2023, after Toyota's proclamation of significant breakthroughs in solid-state technology, CATL's chief scientist, Wu Kai, expressed his skepticism: "Currently, there are still some core issues awaiting resolution with all-solid-state batteries

If Toyota states that they can begin mass production now, I have my doubtsHowever, I cannot predict the situation in 2027. Given CATL's technical capabilities, I find it challenging." Wu's candor is seen as a reflection of CATL's overall stance.

Interestingly, CATL’s founder, Zeng Yuqun, has invested directly in solid-state battery technologyIn March this year, he shared in an interview that CATL has been supportive of solid-state batteries for a decade, and he has kept himself updated with the research team's developments in this field.

Nevertheless, CATL’s approach to research has been one of conservativenessWu Kai has publicly rated CATL's solid-state battery development at a 4 out of 9 on the maturity scale, indicating potential to reach 7 to 8 by 2027. This cautious stance suggests CATL recognizes the complexity of moving towards mass production.

In the same interview, Zeng Yuqun mentioned that the research team's target does not primarily focus on solid-state batteries but rather on sodium-ion batteries and condensed matter batteries

CATL's recent breakthroughs in these areas contrast sharply with the slower development of solid-state batteriesRegarding sodium-ion technology, CATL had launched its first-generation sodium-ion battery back in July 2021 and plans for further industrialization were manifesting in early 2023.

As for the condensed matter battery, it was officially released in April 2024, boasting a unit energy density of up to 500Wh/kg, which surpasses that of traditional lithium-ion batteries by 1.5 timesCATL believes that this new type of battery represents not merely a half-liquid, half-solid solution, but rather a fundamentally new product that could have significant implications for safety and energy efficiencyDespite their ambivalence toward solid-state technology, CATL is evidently dedicating significant resources to this "new species" of battery.

Recent communications from CATL have even posited that condensed matter batteries could enable the electrification of civil aviation vehicles, which, interestingly, has also been cited as an ideal application scenario for solid-state batteries.

Second Reflection: The Global Research Dilemma

Analyzing the history of solid-state battery research, Japan emerges as a pioneer in this field, having heavily invested in it as a strategic industrial focus

Major companies in Japan have harnessed the advantages of being early entrants, with Toshiba developing practical lithium/titanium disulfide solid-state batteries as early as 1983 and Toyota leading in patent filings with over 1,300 solid-state battery patents, amounting to 13% of the global total.

Despite this impressive legacy, Toyota's journey with solid-state batteries has faced significant hurdlesPlans to launch electric vehicles equipped with solid-state lithium-ion batteries in 2020 and to achieve mass production in 2022 have fallen by the wayside, demonstrating the extensive time and effort that has yet to yield the anticipated results.

Interestingly, while domestic players in China may not have the head start that Japan did, they have surged ahead in terms of investment, partly fueled by China’s proactive, top-down development support for solid-state batteries

In May, reports indicated that the Chinese government might invest around 6 billion yuan to support the development of solid-state batteries, with six companies likely to be involved, which invigorated enthusiasm within the domestic sector.

However, even seasoned companies like CATL express frustrations regarding the complexities of solid-state battery developmentZeng Yuqun remarked, "CATL has invested in this area for a decade, and solid-state batteries will have significant advantages only when utilizing new chemical materials and using pure lithium metal as the anode—yet, there are still many challenges ahead to bring that technology to market."

This sentiment is echoed by BYD’s battery CTO, Sun Huajun, emphasizing the daunting challenges faced in achieving mass production of solid-state batteries despite substantial laboratory data and experimental work.

As the discourse on the challenges of achieving all-solid-state battery technology evolves, two key roadblocks persist:

The first is the interface issue

Transitioning from liquid to solid-state electrolyte can minimize leakage, enhancing stability and reducing the risks of thermal runaway, ultimately improving safetyHowever, the natural instability of solid-solid contact may cause the structural integrity of the battery to degrade, affecting not only its cycle life but also overall performance.

The second revolves around dendrite formationDendrites are tree-like formations of metallic lithium that grow during the charging of lithium batteriesShould these dendrites penetrate the membrane, they create internal short circuits that can lead to firesSolid electrolytes theoretically prevent the penetration of dendrites, yet they can still spread through gaps within the electrolyte material, and it turns out that solid electrolytes may actually be conducive to dendrite growth compared to liquid solutions.

Experts have noted that since the inception of global solid-state battery development, these two critical challenges remain largely unresolved

Over a decade has passed, yet these formidable barriers persist.

Looking towards the future, it is hoped that innovations in materials and processes will help overcome these obstaclesHowever, it raises pressing questions about how much investment is needed across the entire supply chain and how long the wait for solutions will be.

Third Reflection: The Fatal Flaws and Industry Pain Points

The enthusiasm for solid-state battery development largely stems from two driving factors: an unyielding pursuit of energy density and a desire to address safety concerns associated with lithium battery technology.

Each time incidents involving electric vehicles or energy storage systems ignite public attention, solid-state batteries seem to capture renewed interest, often hailed in the industry as the definitive solution to lithium battery safety issues.

However, this raises a crucial question: Are solid-state batteries truly 100% safe?

An official press conference held by the National Fire and Rescue Administration highlighted two major safety issues related to new energy sources: one being the inevitability of thermal runaway in lithium batteries, and the second, the unresolved challenges in firefighting and rescue operations related to such incidents.

The inherent nature of lithium and the principles governing the operation of lithium-ion batteries establish a risk of thermal runaway, which is difficult to mitigate

Currently, solid-state batteries still fall within the category of lithium batteries, with potentially higher lithium content, especially as some production lines opt to use lithium metal as anode material in efforts to inhibit dendrite growth and enhance energy density.

Ultimately, in discussions surrounding battery safety, the concept of absolute safety is elusive; instead, it revolves around a relative notion of safety that seeks a balance between safety and economic viability.

In the discourse on energy storage safety, some industry experts suggest a novel approach to fire prevention: controlling the fire or thermal runaway events within the confines of the battery cell or even at the PACK levelThis strategy suggests that efficient mitigation of economic losses can be achieved if potential fire impacts can be isolated, allowing for manageable rectifications.

In essence, advancements in existing battery technology may provide ample space for enhancing reliability and safety—does the ongoing pursuit of solid-state technology remain essential?

Furthermore, it is crucial to recognize that solid-state batteries boast an inherent weakness: lower conductivity that currently fails to meet fast-charging demands

In both the electric vehicle sector and consumer electronics arenas, the requirement for fast charge capabilities is becoming increasingly pronounced.

The charging speed of lithium batteries hinges on the rate at which lithium ions traverse between anodes and cathodes—thus, conductivity is criticalA fitting analogy compares the difference in conductivity between liquid-electrolyte lithium batteries and solid-state batteries to swimming in water versus sand.

While some companies developing solid-state batteries claim significant advancements in fast-charging capabilities—such as Toyota's announcement that their solid-state battery would allow for 1,200 kilometers of range after a mere 10-minute charge—these figures presently stem from experiments rather than verified market performance.

Recent investigations by industry analysts have indicated that most professionals across materials and battery sectors seem to doubt the inherent capacity of solid-state batteries to support fast charging, deeming them unsuitable for high-demand scenarios.

In summary, as safety concerns are not inherently resolved and fast-charging remains a significant obstacle, the once-celebrated advantages of solid-state batteries appear to be fading under scrutiny, exposing underlying vulnerabilities in their development trajectory.