A crowded race gets a deadline
The Solid-State Battery Summit opened in Chicago on Monday, and the room was full of companies that suddenly sound less speculative than they did a year ago. Samsung SDI is already talking about 2027 mass production with BMW as a customer. CATL continues to test semi-solid packs in Chinese showrooms. Solid Power says its sulfide-based cells are closing the cycle-life gap with liquid-electrolyte lithium-ion, and the company is now shipping sample cells to unnamed North American OEMs. For an industry that has spent years promising "five years away," the shift in language matters: the conversation is no longer about whether solid-state batteries work, but about which chemistry reaches high-volume manufacturing first.
The summit's timing reflects that pressure. Organizers at Cambridge EnerTech put more than 60 companies on the agenda, including cell makers, material suppliers, automotive OEMs, and equipment vendors. The presence of BMW, Ford, and Hyundai/Kia delegates signals that car companies are no longer treating solid-state as a research curiosity — they are assigning sourcing teams to it. That is a meaningful change from the last decade, when automakers kept the chemistry at arm's length while they optimized lithium-ion.
Why solid-state still matters
A conventional lithium-ion cell uses a liquid electrolyte to ferry lithium ions between the anode and cathode. That liquid is flammable, which is why thermal runaway in a damaged or overcharged cell can turn into a fire. A solid electrolyte removes most of that risk. It also enables lithium-metal anodes, which store more energy per kilogram than the graphite anodes used in today's cells. The combination — safer chemistry plus higher energy density — is what keeps researchers chasing solid-state even after two decades of slow progress.
Energy density is the number that gets headlines, but cycle life is the number that determines whether a cell survives a vehicle warranty. A solid-state cell that holds 400 Wh/kg but dies after 500 cycles is still a lab experiment. Solid Power reported cycle counts above 1,200 cycles at 80 percent capacity retention in its latest sample generation, up from roughly 800 cycles two years ago. That is still below the 2,000-3,000 cycles automakers expect from current LFP and NMC packs, but the gap is closing.
The chemistry split
Not all solid-state batteries are built the same way. The main branches today are oxide, sulfide, and polymer electrolytes. Samsung SDI and BMW are aligned around an oxide-based, anode-less design with a high-nickel cathode and a silver-carbon conductive layer. The advantage is stability: oxide ceramics handle high voltages without breaking down. The disadvantage is that oxide electrolytes are brittle and hard to manufacture at scale without micro-cracks that degrade performance.
Solid Power, based in Colorado, is betting on sulfide. Sulfide electrolytes conduct ions better than oxides at room temperature, which makes them easier to integrate into existing lithium-ion production lines. The challenge is that sulfides react with moisture in the air, so manufacturing requires dry-room environments that are expensive to build and maintain. Toyota is also working with sulfide cells through a separate partnership with Idemitsu Kosan, which adds another well-funded competitor to the same chemistry branch.
CATL's approach is different again. The Chinese giant has not committed to a pure solid-state design; instead, it is pushing semi-solid batteries with a gel-like electrolyte that shares some safety benefits with fully solid designs while staying compatible with current manufacturing infrastructure. Its condensed Matter battery packs reportedly reach 200 Wh/kg at the pack level and are already in limited production for passenger cars. That makes CATL the only major cell maker with a non-liquid chemistry that is actually shipping to customers today — even if the chemistry is not a true solid-state cell by the strictest definition.
The supply chain behind the cell
Solid-state batteries need more than a new electrolyte. The anode, cathode, separator, and packaging all change when you remove the liquid. That means new material suppliers, new coating equipment, and new inspection tooling. 3M, DuPont, and Ube Industries are all developing solid-electrolyte powders and binder chemistries. On the equipment side, companies that coat electrodes and assemble cells are redesigning their tools to handle brittle ceramic sheets and ultra-dry assembly environments.
The equipment shift is where Japan and Germany think they can keep an edge. Even if China leads in cell chemistry patents and pilot lines, much of the precision coating and laminating equipment still comes from Japanese and German vendors. Tariff and export-control risks could reshape that flow, but for now the supply chain is global. A sulfide cell designed in Colorado may use electrolyte powder from a Japanese chemical firm and assembly tools from a German engineering company.
What comes next
BMW says it wants a solid-state prototype vehicle by 2027, with production to follow if the prototype meets cycle-life and cost targets. Solid Power targets 2027 for its first high-volume cell line in Colorado, with a second line planned for Germany. Samsung SDI is building a dedicated solid-state line at its South Korean complex and plans to supply BMW from there. Toyota has been quiet on exact dates but is known to be testing solid-state packs in Lexus prototypes.
The risk is not technical — it is economic. A solid-state cell will cost more than a lithium-ion cell for several years after launch, and automakers are already under pressure to keep EV prices low. If the first solid-state packs end up in low-volume luxury cars rather than mass-market models, the technology will take longer to reach the buyers who would benefit most from longer range and faster charging.
For now, the most credible bet is that solid-state batteries will arrive first in premium cars and specialty vehicles, where buyers tolerate higher prices for better performance. From there, manufacturing scale and material cost improvements should push the technology downmarket. That is the pattern lithium-ion followed in the 2010s, and there is no reason to expect solid-state to skip it.
For more on the chemistry and manufacturing race, see our Battery Tech archive and Semiconductors coverage for the chip designs that manage these cells. Sources: Solid-State Battery Summit agenda, Solid Power Samsung SDI partnership update, and MotorTrend comparison of solid vs semi-solid approaches.