The hype surrounding solid-state batteries is dwindling, causing automakers to explore other options.

• Electric vehicle (EV) batteries have long been touted as the "holy grail" of sustainable driving. Supporters claim they provide safer, more affordable, and more powerful batteries for EVs, as well as faster charging times.
• Another option is semi-solid-state batteries, which combine a solid electrolyte and liquid electrolyte design.
• "Julia Poliscanova from Transport & Environment stated, "Five years ago, discussing solid-state batteries would have made me extremely enthusiastic. However, today, there seems to be some kind of obstacle.""

The development of solid-state batteries for electric vehicles is progressing, but analysts predict that automakers may soon shift their focus to a different scientific breakthrough.

Solid-state batteries, with their solid electrolyte made from materials such as ceramics, have long been touted as the sustainable driving solution. Unlike conventional lithium-ion batteries, which use liquid electrolyte, solid-state batteries are a game-changer in the world of eco-friendly transportation.

Theoretically, this new technology is capable of storing more energy in a smaller battery volume than lithium-ion batteries. Supporters claim that it provides safer, more affordable, and more powerful batteries for electric vehicles, as well as faster charging times.

Billions of dollars have been invested by automakers in researching solid-state batteries, and they have collaborated with developers to create their own versions for mass production.

Toyota, a Japanese automaker, aims to bring solid-state batteries into mass production between 2027 and 2028. The company expects its latest breakthrough in improving the durability of its technology to result in a battery that can offer a range of 1,000 kilometers (621 miles) and a charging time of just 10 minutes.

In April, Nissan Japan announced plans to launch solid-state batteries for electric vehicles (EVs) by early 2029. Meanwhile, Factorial, a battery startup based in Germany and the US, revealed in September that they are collaborating on a solid-state battery that will be ready for production by the end of the decade. Additionally, Factorial has joint development agreements with automakers such as Stellantis, Hyundai, and Kia.

Nearly 300 miles (or 483 kilometers) is the average range for EVs in the U.S. on a single charge, according to the Environmental Defense Fund. The time it takes to charge a battery-powered EV can range from 20 minutes to several hours, depending on the car and the speed of the charging point.

Wood Mackenzie analyst Max Reid stated that solid-state batteries are in the early stages of commercialization.

Reid stated via video call that the results are promising, with increased safety, energy density, and charging speeds, which he believes is the main benefit of solid-state technology.

Although there is excitement about the possibility of solid-state batteries being released, analysts are uncertain about their timeline for market availability.

Semi-solid-state batteries

The issue with solid-state batteries, according to Wood Mackenzie's Reid, is that they expand during charging, which leads to the degradation of the cell after prolonged recharging.

If we had discussed solid-state batteries five years ago, I would have been thrilled about them, said Julia Poliscanova, senior director for vehicles and e-mobility supply chains at Transport & Environment, during the Paris Motor Show.

"Despite the distance between pilots and commercialization, there exists a barrier or blockage that prevents progress. Whenever I engage with automotive executives at battery conferences, they consistently respond with the same answer: "We are five to seven years away.""

Poliscanova stated that lithium-ion batteries have been improving significantly, with incremental improvements in cheaper technology. However, the attractiveness of investing all attention in solid-state technology may have diminished due to this advancement.

Some analysts suggest that semi-solid-state batteries could serve as a bridge between solid and liquid electrolyte batteries.

In China, semi-solid batteries have been commercialized to a significant extent, according to Reid, who believes that this technology is a compromise that will eliminate the need for full solid-state batteries.

Reid stated that with slower demand for electric vehicles (EVs) in the West and challenges with solid-state technology, there may be negative or not-so-positive announcements regarding full solid-state technology. However, there could be a pivot to semi-solid technology as it is recognized as a better transitional technology for this decade's needs.

Chinese companies, such as CATL, WeLion, Qingtao Energy, and Ganfeng Lithium, are primarily leading the development of semi-solid-state batteries.

Nio has commercialized 150-kilowatt hour semi-solid-state batteries for its EVs, with a range of up to 1,000 kilometers, while Ganfeng LiEnergy, a subsidiary of Ganfeng Lithium, produces semi-solid-state batteries for EVs with a range of 530 kilometers.

Lithium-based batteries 'still the way to go'

Poliscanova from Transport & Environment stated that she observes advancements in semi-solid-state batteries in China, as whoever comprehends the art of battery production will continually innovate.

The focus on lower cost innovations has been greater than on solid-state technology, likely due to the fact that performance is already satisfactory in the vehicle industry. While trucks and planes are relevant, in the vehicle space, a range of 600 to 800 kilometers is sufficient.

There is doubt among some people about the imminent shift to semi-solid batteries and the excitement surrounding the widespread adoption of solid-state batteries in the near future.

According to Michael Widmer, head of metals research at Bank of America global research, lithium-based batteries are still the preferred option in the EV space for now, as stated on Oct. 9 during an interview on CNBC's "Squawk Box Europe."

He stated that it would likely remain the primary source for the next five to ten years.