Nissan Validates 23-Cell Prototype Pack as China's Greater Bay Technology Ships First All-Solid-State A-Samples
Nissan's 23-layer solid-state prototype meets vehicle performance targets; GAC-backed Greater Bay Technology rolls out first A-samples aiming for GWh production in 2026.
Overview
Two separate milestones reported in April 2026 illustrate how the global push toward all-solid-state batteries is moving from single-cell laboratory demonstrations toward the more demanding engineering work of prototype packs and pilot production. Nissan announced that a prototype battery assembly containing 23 stacked cell layers has met vehicle-grade charge and discharge targets, while Greater Bay Technology — a startup backed by China’s GAC Group — reported that its first A-sample all-solid-state cells have passed critical safety tests and that GWh-scale production could begin before the end of 2026.
This follows earlier reporting by The Machine Herald on the broader commercialization race underway across Chinese and Western battery developers.
What We Know
Nissan: From Single Cells to a Vehicle-Grade Pack
According to Electrek, Nissan has stacked up to 23 battery cell layers into a single solid-state prototype pack — a configuration the company describes as sufficient for actual vehicle use. The pack met required charge and discharge performance targets, marking progress beyond single-cell laboratory tests to a form factor that could eventually be integrated into a production vehicle.
Nissan opened an all-solid-state battery pilot production line at its Yokohama facility in January 2025 and maintains its target of launching its first solid-state-powered EV in fiscal year 2028, according to Electrek. The same report notes that solid-state technology, if successfully commercialized, could roughly double the driving range of comparable lithium-ion vehicles, potentially exceeding 1,000 km on WLTP testing cycles.
For electrode manufacturing, Nissan is partnering with US-based LiCAP Technologies. As reported by Electrek, LiCAP’s Activated Dry Electrode process eliminates the solvent drying steps used in conventional electrode production, which reduces costs and shortens manufacturing time — an important factor as the industry works toward cost-competitive solid-state cells at scale.
Greater Bay Technology: A-Samples Cleared Safety Tests
On April 14, GAC-backed Greater Bay Technology announced the rollout of its first A-sample all-solid-state battery cells. As reported by Interesting Engineering, the cells achieve energy densities of 260–500 Wh/kg, substantially above the 150–200 Wh/kg range typical of current lithium-iron-phosphate packs, and support stable fast charging at 2C to 3C rates — a capability that has historically been difficult to achieve with solid electrolytes.
Safety performance was a central feature of the announcement. According to Interesting Engineering, the cells contain no liquid electrolyte and survived nail penetration and thermal shock tests without fire or explosion, addressing the thermal runaway risks associated with liquid-electrolyte lithium-ion batteries.
The company’s electrolyte uses what it describes as a deep eutectic composite system combining three material techniques — SDE-cured deep eutectics, CFS antiperovskites, and nematic nanoconfinement — designed to improve both ionic conductivity and structural stability, according to Interesting Engineering. Greater Bay has filed more than 50 patents covering its electrolyte formulas and manufacturing processes.
The company targets GWh-scale mass production by late 2026, with cells initially slated for GAC’s Hyptec vehicle lineup, as reported by both Electrek and Interesting Engineering.
What We Don’t Know
Significant uncertainties remain across both programs.
For Nissan, the 23-layer prototype is a necessary engineering milestone but not a production-ready battery. Moving from a validated prototype to automotive-grade cells that meet stringent durability, thermal cycling, and cost requirements involves challenges Nissan has not yet detailed publicly. Manufacturing yield for solid electrolyte layers at scale — which must be free of defects that would cause short circuits — remains an unsolved challenge across the industry. Nissan has not disclosed the specific solid electrolyte chemistry used in its current prototype, nor a publicly stated cost-per-kWh target.
For Greater Bay Technology, A-sample validation is an early stage of automotive qualification. Supply chains typically require B-sample and C-sample validation before mass production begins, and the company’s stated goal of GWh-scale production in 2026 is aggressive by industry norms. Independent verification of the reported energy density and cycle-life figures has not been announced. It is also unclear how the cells perform across extended charge-discharge cycles under the temperature variations common in real-world vehicle use.
More broadly, no solid-state battery manufacturer has yet demonstrated cost parity with lithium-ion at commercial scale. Solid electrolyte materials and the processes required to manufacture defect-free layers remain significantly more expensive than established lithium-ion production, and a credible path to matching the sub-$80/kWh levels achievable with conventional chemistries has not been publicly demonstrated by any player in the field.