Chinese battery manufacturer Greater Bay Technology (GBT) has started series production of all-solid-state battery cells at its plant near Guangzhou. The company claims this is a world first, as all benchmark players are still trialing pilot lines.
GBT, a battery cell developer backed by automotive group GAC, has officially opened its first factory for solid-state cells. The initial capacity is 1 GWh, a modest figure, but the site has an additional 3 GWh available for conversion if demand grows.
Difficult to predict
The word “conversion” matters in this case, as GBT didn’t build its factory from scratch. Interestingly, the developer used an existing lithium-ion line. In fact, the production hall can still switch between the two battery types, which gives the strategy an economic advantage. All solid-state technology is expensive at this point. The market size is difficult to predict.
Production is expensive as well. Most serious solid-state programs, like those from Toyota, Samsung SDI, or CATL, use sulfide electrolytes. These disintegrate on contact with moisture, so production places high demands on facilities that can maintain oxygen-free drying throughout.
That complicated process demands a level of know-how and experience that isn’t common. It also shouldn’t allow easy switching between battery types.
Curing inside the cell
But GBT sidestepped the problem with an organic-inorganic composite electrolyte. It enters the cell as a liquid precursor, then cures in place, forming an elastic interface with the electrodes.
Because the electrolyte forms inside the cell, conventional lithium-ion equipment can be used. The oxygen-free environment is only needed partially, for filling the electrolyte.
GBT founder and CTO Huang Xiangdong said: “This is not a new line built from scratch; it is an existing line with a new core.” The A-samples rolled off in April, and now series production has already begun. Only half a year between prototype and production is pretty fast for battery innovation.
Genuine solid-state
There’s no discussion either about the true nature of GBT’s solid-state cells. Often, semi-solid-states are marketed as the real deal, but they are entirely different species, and much easier to scale up for mass production.
But the National Power Battery Innovation Center in China has tested GBT’s production cells. They are the first verified under China’s new regulatory framework: standard GB/T 48093.1-2026.
That standard separates genuine all-solid-state cells from the semi-solid and hybrid products that have been advertised under the same label. It only enters into force in 2028, but GBT already meets the requirements.
And in Europe?
However, GBT has not published any figures. But for a cell intended for vehicles, energy density and cycle-life will prove crucial.
Europe’s most concrete solid-state asset is ProLogium’s gigafactory in Dunkirk. It will be the first large-scale solid-state capacity on European soil, and it will be Taiwanese-owned. Volkswagen is following a route to license QuantumScape’s technology into its own PowerCo plants. That would install production in Europe but leave the core intellectual property American.
We might see GTB’s cells in Europe, though. The company has an agreement with Flynt, a Dutch start-up in the LCV sector targeting commercial fleets.
