What’s going on with Donut Lab's so-called super battery?

In January, a Finnish-Estonian startup named Donut Lab claimed to have developed a truly solid state battery, a long-sought-after innovation in the technology industry. The company's cell wasn't just solid state; it boasted that it was made from cheap and easily available materials, would charge to full capacity in a few minutes, and last for hundreds of years. If such a device were real, it would revolutionize the way we power our world, from electric vehicles to everyday electronics. However, the skepticism surrounding Donut Lab's claims has only grown as the company struggles to provide concrete evidence of its breakthrough.

Solid state batteries have been a hot topic in the industry for years. Conventional batteries, which are commonly found in electronics and electric vehicles (EVs), have improved significantly over the past few decades, but they still have limitations. These cells typically use liquid or gel polymer as an electrolyte. The electrolytes are a major cause of thermal runaway, a phenomenon where the heat of a battery increases exponentially, leading to battery failure and even fires. Additionally, they require a consistent temperature for optimal performance and must be handled with care. This is why the industry has been racing to develop solid state batteries that eliminate the need for liquid or gel polymer electrolytes.

Solid state batteries offer several advantages over conventional batteries. They have a higher energy density, meaning they can store more energy in a smaller and lighter package. This would be particularly beneficial for EVs, where weight and size play a crucial role in determining performance, range, and efficiency. Furthermore, solid state batteries are less prone to thermal runaway and can operate in a much wider temperature range. This makes them more reliable and safer, which is a significant concern for both consumers and manufacturers.

We are already seeing semi-solid batteries entering the market, with fully-solid cells expected in the near future. Chinese battery giant CATL announced at the end of 2025 that it had started small-scale production of solid state batteries. This development is a testament to the industry's commitment to advancing battery technology and addressing the challenges posed by conventional batteries.

Donut Lab's claims, however, have raised eyebrows and doubts. The company's battery was not just a solid state innovation; it promised to be made from inexpensive and readily available materials. This would significantly reduce production costs and make the technology more accessible to a wider range of applications. The prospect of charging to full capacity in just a few minutes and achieving a lifespan of hundreds of years is tantalizing, but it has also led many to question the credibility of these claims.

As Donut Lab has worked to demonstrate the validity of its technology, critics and skeptics have found numerous points of contention. Some have pointed out inconsistencies in the company's data and lack of transparency in its research and development process. Others have questioned the feasibility of certain aspects of the battery's design, such as the use of cheap materials and the ability to charge so quickly without compromising safety or longevity.

The skepticism surrounding Donut Lab's battery has led to a heated debate within the technology community. Some experts argue that the company's claims are premature and that it needs to provide more rigorous testing and validation before making such bold assertions. Others contend that the hype around Donut Lab's technology is a necessary part of driving innovation and pushing the boundaries of what is possible in battery research.

Despite the controversy, Donut Lab has continued to push forward with its vision. The company has released several videos and demonstrations aimed at showcasing the capabilities of its battery, but these have often been met with skepticism and criticism. Some observers have accused the company of engaging in a "dog and pony show," using flashy presentations and marketing tactics to obscure the lack of concrete evidence supporting its claims.

As the debate continues, it is essential to consider the broader context of battery technology and the challenges facing the industry. The push for solid state batteries is driven by a need to address the limitations of conventional batteries, such as their susceptibility to thermal runaway and their limited energy density. The potential benefits of solid state batteries are significant, and the race to develop viable technology is well underway.

In this landscape, Donut Lab's claims are not unique. Other companies and research institutions are also working on solid state batteries, each with their own set of challenges and hurdles to overcome. The key to success will likely lie in finding a balance between innovation, practicality, and safety, as well as ensuring that the technology can be scaled up and commercialized effectively.

For now, the future of Donut Lab's battery remains uncertain. While the company has generated a significant amount of buzz and interest, the skepticism surrounding its claims has made it difficult to gain widespread acceptance. As the debate continues, it will be interesting to see whether Donut Lab can provide the evidence needed to convince skeptics and validate its groundbreaking technology. Only time will tell if this Finnish-Estonian startup's vision of a truly revolutionary battery is just a dream or a reality that could change the world.