The 1915 Detroit Electric Brougham was powered by lead-acid batteries, and so was the first generation of the General Motors EV1 back in 1996. The 1915 car could reportedly travel 80 miles (129 km) on a single charge, and the EV1 wasn’t much better, with a range of 70 to 100 miles (113 to 161 km).
However, today’s lithium-ion (Li-ion) batteries are routinely able to provide ranges of 300 miles (483 km) and outliers like the Lucid Air Grand Touring offer more than 500 (805 km) of range. But traditional Li-ion chemistry also has its limitations, and researchers now have the funding, including from the Biden Administration, to deliver something better.
Automakers are increasingly focusing on the long-delayed promise of solid-state batteries. With no liquid electrolyte, these batteries can be lighter, safer (with reduced fire risk), faster to recharge, and more energy dense while still being able to deliver ranges of 600 miles (965 km) or more.
Toyota, Nissan and Honda, and some U.S.-based startups such as Solid Power and QuantumScape are working to commercialize solid-state batteries in the near term. The big challenge is moving electrons through a solid (often a ceramic), and there remain hurdles related to cost, materials availability (the batteries tend to be big lithium users), stability and stubbornly high surface resistance that scientists call the “electric double layer” (EDL) effect.
But researchers are getting closer to a viable solid-state battery, and Toyota, working with Japanese petroleum refiner partner Idemitsu Kosan, said it will start to produce commercial-grade cells in 2027 or 2028. Koji Sato, President and CEO of the Toyota Motor Corporation, said this will lay the foundation for mass production. Toyota claims these batteries will have more than 1,000 kilometers (621 miles) of range (based on the CLTC, China Light Duty Vehicle Test Cycle standard) and can fast charge in around 10 minutes.
Toyota: Hedging Bets
Hedging its bets, Toyota also is working on so-called high-performance lithium batteries with a high-nickel cathode and a bipolar structure for that same timeframe. These packs are projected to yield 621 miles of range and a fast-recharging time of less than 20 minutes. Toyota’s sole U.S. EV, the bZ4X, offers just 252 miles (406 km) of range.
Toyota is working on a second generation of advanced solid-state batteries that is targeted to provide ranges of more than 1,200 km (745 miles) with a to-be-determined delivery date. Toyota’s Sato said in a statement that “the biggest challenge [for solid-state batteries] is durability. A long-standing technical issue has been that repeatedly charging and discharging the battery causes cracks between the cathodes and anodes and the solid electrolytes, degrading battery performance.” Toyota has been working on this issue with Idemitsu Kosan since 2013 and announced in October 2023 that the two companies have agreed to work together to develop mass-production technologies for solid-state batteries, including a flexible solid electrolyte that resists cracking while delivering high performance.
Toyota told SAE Media that achieving its stated solid-state range “will require the charging of high-capacity batteries, which we believe will necessitate ultra-high-output rapid chargers even more powerful than the current fast-charging standard of 150 kilowatts.” The company said there are no cost estimates for producing either future generation of solid-state batteries and the automaker is not betting the farm on solid-state batteries, either. “The current thinking is that there are different chemistries that achieve different goals,” Toyota said. “It is better for us to have multiple options, even within the segment of battery electric vehicles.”
Nissan reportedly plans soild-state battery commercialization by 2028, and Honda, has informally floated 2028 or 2029 for their units. However, getting the batteries from a manufacturing-feasible cell to actual incorporation in a production car’s battery pack is a significant step.
Rory McNulty, Senior Analyst for Benchmark Mineral Intelligence, believes the first drivable solid-state cars from western OEMs will appear between 2028 and 2030 at the earliest. “It is important to understand the formal automotive qualification procedure, which takes between four to six years depending on the pace of progress,” he told SAE Media. “No solid-state battery innovator outside of China has yet entered this procedure, though three have doubled down to enter by the end of 2023.”
Benchmark projects that less than four gigawatt-hours of prototype solid-state batteries will be produced in 2023 by the companies it is tracking that are working on the technology. “To achieve anywhere near mass-market penetration, manufacturing processes must be scaled into the hundreds of megawatt-hours, then to the many gigawatt-hours, if emerging technologies want to compete on cost with the incumbent li-ion batteries,” McNulty said.
Biden’s IRA Encouraging Startups
The federal National Blueprint for Lithium Batteries 2021 to 2030 set a goal of demonstrating, by 2030, the at-scale production of solid-state batteries that are cobalt- and nickel-free and that meet a production cost of less than $60 per kilowatt-hour, with a specific energy of 500 watt-hours per kilogram.
The Biden Administration’s Inflation Reduction Act also provides income tax credits for EVs that, among other things, source their batteries in North America. That’s part of the picture for San Jose, CA’s QuantumScape, which has a timetable similar to Toyota’s and plans to build its batteries in the U.S.
QuantumScape has succeeded in developing a flexible, non-crack-prone separator in a lightweight and compact cell design with a lithium-metal anode that, in testing, has shown it can be recharged 1,000 times (the equivalent of 300,000 miles in a 300-mile-range battery) while using only “slightly more” lithium than standard Li-ion cells, according to QuantumScape Chief Technology Officer and Co-Founder Tim Holme.
Holme told SAE Media that an auto OEM’s evaluation of a 24-layer prototype cell retained more than 95 percent discharge energy retention after 1,000 full cycles. The company dispenses with conventional silicon or graphite anodes. Instead, when the cell initially charges, Li-ion ions plate on top of the solid-state ceramic separator, serving as the pure lithium-metal anode after that.
The company also claims to have addressed the thorny problem of “dendrites,” which are branch-type formations that can spread out between the electrodes and cause short circuits. Dendrites are a particular challenge in solid-state batteries.
In late 2022, QuantumScape showed 24-layer, A Sample cells to automakers. The company’s higher-volume B Samples are expected to arrive in 2025 and could be evaluated in customer test vehicles. C Sample, production-ready cells qualified by the OEM customers will come after that.
QuantumScape has funding from Volkswagen Group and Bill Gates and is also working with “two established global luxury OEMs” and one “pure-play EV company.” However, In January 2024, Reuters reported that with QuantumScape progress “dogged by delays,” VW was in development talks with France-based Blue Solutions, which currently makes batteries for EV and buses and also is intent on commercializing a solid-state design for light vehicles.
Colorado-based Solid Power, with Ford and BMW as partners, has raised $700 million to date. CEO John Van Scoter told Autoweek the company has “a goal to get our solid-state battery cells into automotive qualification with one of our partners this year, and we believe we are still on track. That will kick off a qualification process that would put our commercialization later this decade.”
Solid Power’s A Sample cells have a silicon anode, a lithium-nickel-manganese-cobalt-oxide (NMC) cathode, and a sulfide solid electrolyte (made with earth-abundant materials). The company’s website said it expects a 15 percent to 35 percent cost advantage over existing Liion chemistry batteries at the pack level.
McNulty’s projection is similar. He noted that a partnership between Chinese battery company WeLion and automaker NIO is leading to the planned release late this year of the ES6 SUV with a 150-kWh oxide-based solid-state battery and a reported 577-mile (929 km) range. The problem, McNulty said, is that “the anode used in this technology is a silicon-graphite composite, so not yet the silicon-based or lithium-metal break-through that solid-state has promised.”
McNulty said that cars with solid-state batteries will “begin to take up market share in luxury segments between 2030 and 2035,” followed by gradual adoption into the mass market.» In short, the rise of solid-state batteries will be a transition rather than a sudden switch.”
At the 2023 Battery Show North America in Novi, MI, Bill Kephart of P3 Group, an automotive-industry consultancy, said to expect a 3 percent to 5 percent penetration rate for solid-state batteries in 2030. He cited four factors — performance, manufacturability, supply chain, and cost — as the primary areas in which solid-state technology must improve before being able to reach high-volume potential.
In a Battery Show presentation titled “Status, Challenges and Needs of Solid-State Batteries, Alvaro Masias, Cell Technology Research Supervisor at Ford, said bluntly that while good progress has been made in the development of solid-state batteries, it is “very difficult to see how [the technology] would be cost-competitive in the near-term.”
This article was written by Veteran Journalist Jim Motavalli, a regular contributor to The New York Times, Barron’s, MediaVillage, and Wharton School Reports, focusing on sustainable trends in mobility and business.