Honda has started production on solid-state batteries. But will they actually live up to the hype?
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What Honda’s Solid-State Battery Breakthrough Tells About The Future Of EV Tech
Andrew Koopman
33–42 minutes
Late last year,
Honda revealed that its solid-state battery pilot production line is up and running, with actual production slated to start a couple of months ago in January 2025. This facility, located at the company’s Sakura plant in Japan, is not just an R&D lab. It’s producing actual solid-state battery prototypes with the goal of scaling them for use in future EVs.
While the technology is still far from ready for mass production, Honda’s ability to move beyond simulations and into physical manufacturing could signal a turning point. Not just for the company, but for the EV industry as a whole.
In order to give you the most up-to-date and accurate information possible, the data used to compile this article was sourced from Honda and other authoritative sources.

Honda may become the first car company to get an all-solid-state battery into an actual car. Here is how they're doing it.
Honda's Solid-State Battery Factory Is Already Operating
The Pilot Line Is Ahead Of Schedule Compared To Rivals
Other Automakers Are Still Stuck In The Planning Stage
Toyota
While
Honda is now producing physical battery cells on a pilot line, most of its competitors remain at earlier stages of development. Toyota, for example, has
announced that it plans to introduce solid-state batteries by 2027, but its efforts remain largely experimental, focused more on prototype vehicles and lab-based testing. Similarly, companies like
Ford,
BMW, and
Volkswagen have all entered partnerships with battery startups or research institutions, but are lagging behind Honda when it comes to actual production.
Solid-state battery technology is an unfamiliar territory, but thankfully it's an easy topic to be well-informed on.
The Solid-State Hype Has Gone On For Too Long Without Results
Automakers Have Relied Too Heavily On Theoretical Test Results
JLStock | Shutterstock
For years, announcements about SSB advancements have leaned heavily on lab-based metrics
like energy density figures, cycle life projections, and charging time estimates. Automakers have frequently touted promising test data, like
Toyota's 745-mile range thanks to SSBs, suggesting breakthroughs were just around the corner. However, translating those figures into real-life batteries that can be produced reliably and at scale has proven to be far more difficult.
Battery Startups And Partnerships Have Created More Noise Than Progress
Mercedes-Benz
Over the past several years, automakers have rushed to partner with startups promising to deliver next-generation battery tech. Solid Power, QuantumScape, and SES are just a few of the names that have
entered agreements with major players like BMW and VW. These partnerships often generate headlines, press events, and investor interest, but the actual pace of progress has been slow. Delays in prototype delivery, challenges in scaling up production, and shifting project timelines have become common.
Part of the problem lies in overly relying on external partners with unproven technologies. Many startups are still working through basic scientific challenges or scaling problems, leaving automakers stuck with no way forward of their own. As mentioned above, Honda is developing its SSBs entirely in-house. This allows for tighter integration between design, production, and testing, meaning the carmaker doesn't have to rely on anyone other than itself, which can be a huge bonus when working with unproven technology like this.
Related
Mercedes-Benz may finally be ready for solid-state battery production.
QuantumScape via YouTube
Roll-Pressing Electrolytes For Better Contact And Efficiency
According to Honda, one of the biggest challenges in solid-state battery production is ensuring consistent contact between the solid electrolyte and the electrode materials. Without trying to get too technical here, even though the engineer in me is eating this stuff up, traditional lithium-ion batteries, like the ones used in EVs today, use a liquid electrolyte that naturally fills the gaps between the anode and cathode materials, ensuring consistent contact throughout the cell. In contrast,
SSBs rely on powdered or compressed solid electrolytes, which can leave microscopic voids and uneven surfaces that interfere with conductivity. These gaps increase internal resistance, reduce efficiency, and can lead to premature degradation.
To address this, Honda is using a proprietary roll-pressing process on its pilot production line to compress solid electrolyte layers with greater consistency. The goal is to improve uniform contact between materials across the cell structure, which could enhance energy transfer and reduce the likelihood of performance loss over time. By focusing early on this aspect of manufacturing, Honda is getting ahead of the game by ensuring their production methods are viable at scale.
Another major concern in SSB development is the formation of lithium dendrites, which are
microscopic needle-like filaments that grow inside the cell and can cause internal short circuits. These structures are especially dangerous in solid-state designs, where a solid electrolyte can crack under pressure or allow dendrites to punch through layers. Honda is working on incorporating polymer-based separators within its solid-state cells to help mitigate this issue.

Hyundai and Kia say their new solid-state batteries won't be around until at least 2030.
Solid-State Batteries Still Have A Long Road To Real-World Use
Semi-Solid-State Batteries Are Already In Limited Use
Nissan
Despite the excitement surrounding solid-state technology in recent years, no major automaker has delivered a full SSB in a production vehicle. Some EVs on the road today use what are referred to as semi-solid-state batteries, cells that incorporate solid electrolytes with liquid components to improve conductivity and durability. These designs offer a middle ground between traditional lithium-ion and full solid-state, but they still fall short of the safety and performance targets solid-state tech promises.
Full Solid-State EVs Could Be Market-Ready By Late Decade
Mercedes-Benz
Honda hopes that its solid-state batteries will be
used in future EV models, with a goal of applying the technology to next-generation vehicles by the latter half of the 2020s. This timeline is roughly in line with
Toyota and other automakers who project SSB use near the end of the decade. However, Honda’s ability to begin pilot manufacturing now gives it more time to refine production methods and test durability in real-world conditions.