Solid-state batteries promise to boost range of electric vehicles while simultaneously reducing charge times and costs, compared to the liquid-state batteries in use today.

It's why most major automakers are developing solid-state batteries, and one of the leaders could just be Toyota, an automaker that until recently was reluctant to develop cars powered by batteries, favoring hydrogen fuel cells instead.

Japan's Nikkei partnered with Tokyo-based research firm Patent Result to study the number of solid-state battery patents filed with the World Intellectual Property Organization between 2000 and March 2022, for 10 specific countries and territories.

In a report published on Thursday detailing the results of the study, Nikkei said Toyota was the leader with 1,331 known patents, with Panasonic Holdings coming in a distant second with 445 patents. Third place went to another Japanese company, Idemitsu Kosan, which had 272 patents.

Toyota has been researching solid-state batteries since the 1990s, and its patents cover a wide ranging field that includes battery structure, material and manufacturing processes, according to the Nikkei. Toyota also has a joint-venture company with Panasonic to manufacture batteries, including solid-state designs. Toyota is also part of a Japanese consortium researching the technology. Other partners include Honda and Nissan.

Patents aren't necessary a sign of impending production but Toyota has promised to launch a vehicle with solid-state batteries by the middle of the decade, albeit a hybrid and not a full-electric vehicle.

Toyota in 2020 started testing solid-state batteries in a one-off EV based on the Concept-i from 2017. The automaker said at the time the batteries deliver higher output because of the fast movement of ions within them, but their short service life remains an issue that needs solving.

Nissan last year said it plans to have EVs with solid-state batteries on sale by 2028. The automaker estimates its solid-state batteries will cost approximately $75 per kilowatt-hour by that date, and the automaker aims to eventually reduce this to $65 per kwh, at which point Nissan will be able to build EVs at the same cost as internal-combustion models, the automaker said. Current battery costs are closer to $130 per kwh, on average.

Volkswagen Group is also developing solid-state batteries which the automaker estimates will boost range by 30% compared to current liquid-state batteries of similar size, and enable an 80% charge in around 12 minutes. VW Group expects to introduce its first solid-state batteries after 2025.

Note, Toyota isn't waiting around for solid-state batteries before it moves with full force into EVs. The automaker late last year announced plans to launch 30 EVs across its Toyota and Lexus brands by 2030, starting with the 2023 BZ4X and related 2023 Lexus RZ.