All-Solid-State Battery Industry in Mid-2026: TRL Milestones, QuantumScape's Progress, and Solivis's Series C

The all-solid-state battery (ASSB) industry reached a critical inflection point in 2026. According to TrendForce's Q2 2026 quarterly report, the sector has moved beyond laboratory proof-of-concept into a dedicated engineering validation phase . Technology Readiness Levels (TRLs) have advanced significantly across Japan, South Korea, and China, and a wave of new investment and policy support is accelerating the path toward commercial production .

This article provides a sourced overview of the key developments as of mid-2026, including TRL progress by region, the state of lithium sulfide costs, QuantumScape's commercialization milestones, South Korea's Solivis Series C, and the expansion of ASSB applications beyond electric vehicles.

Engineering Validation and TRL Advancement by Region

The shift from laboratory materials research to engineering-scale manufacturing is the dominant theme of 2026. TRL assessments provide a standardized way to measure this progress .

Japan (Toyota, Honda, Nissan): Japanese manufacturers hold a slight lead in small-scale pilot production. Their automotive-grade products have passed key performance validation and are now accelerating module-level evaluation for vehicle integration . Sulfide-based systems, such as those developed by Toyota, are broadly assessed at TRL 5–6, targeting pilot production by 2027–2028 .

South Korea (Samsung SDI, SK On): Samsung SDI is targeting mass production of 900 Wh/L sulfide ASSBs in the second half of 2027, backed by a 25 trillion won (~$17.77B) investment plan through 2040 . SK On pulled forward its own commercialization timeline to 2029 .

China (CATL, BYD, Zhongke Yuanben): CATL officially announced plans to begin pilot production of all-solid-state batteries in 2027, following a similar announcement from BYD . In late July 2026, Zhongke Yuanben completed China's first real-vehicle road test of a sulfide-based ASSB, validating full-stack technology integration . Multiple Chinese OEMs, including CATL, BYD, and Geely, have initiated equipment tenders for pilot lines . CATL itself is currently at TRL-4, targeting small-batch production by 2027 . The industry consensus timeline for China remains: semi-solid (hybrid) installation in vehicles by 2026, small-batch all-solid-state by 2027, and large-scale commercialization post-2030 .

Lithium Sulfide Costs and Electrolyte Capacity

While the specific user-requested figure of ~$219/kg for lithium sulfide was not directly confirmed in sourced results, sourced pricing data from Shanghai Metals Market shows battery-grade lithium sulfide at approximately $254.06/kg (VAT excluded) as of January 2026, with a trading range of $228.65 to $279.46 .

Gotion High-Tech has outlined an ambitious capacity ramp: it plans to reach 300 tons/year of lithium sulfide in 2026 and 50,000 tons/year by 2030, alongside 100,000 tons of solid-state electrolyte capacity . The company notes that 70–80% of the cost of a sulfide ASSB comes from the electrolyte, and 70–80% of the electrolyte cost comes from lithium sulfide .

Meanwhile, China's first national standard for automotive solid-state batteries (GB/T 43568-2026) took effect on July 1, 2026 . Multiple hundred-ton-level sulfide electrolyte production lines commenced commissioning in China in Q3 2026, signaling a shift toward ton-level transactions for these critical materials .

QuantumScape Commercialization Progress

QuantumScape reported strong operational and financial progress in the first half of 2026 .

• Capital-light licensing model: The company avoids large-scale factory capital expenditure by licensing its technology to manufacturing partners like PowerCo (Volkswagen) . A revised PowerCo agreement reduced total possible payments from ~$131 million to ~$75 million but also lowered project expenses .
• Cumulative customer billings: As of the J.P. Morgan Automotive Conference in August 2026, QuantumScape reported $40 million in cumulative customer billings from development and sampling work . First-half 2026 billings totaled $21.8 million, already exceeding full-year 2025 billings of $19.5 million .
• Eagle pilot line: Core tools on the automated pilot line in San Jose are operating at >90% uptime, and management aims to double cell output in the second half of 2026 to accelerate sample shipments .
• QSE-5 cell: The company's first commercial product delivers 800 Wh/L energy density, more than 300 Wh/kg, and a 10–80% charge time of about 12 minutes .
• New verticals: QuantumScape formalized three divisions: QSEV (electric vehicles), QSDC (AI data centers), and QSAS (aerospace and defense) .
• OEM partners: Beyond Volkswagen and PowerCo, QuantumScape is working with Honda and two additional top-10 global automakers .

South Korea's Solivis: Series C and Expansion

Solivis, a South Korean manufacturer of sulfide-based solid electrolytes for all-solid-state batteries, closed a Series C funding round in mid-2026 .

• Funding value: The round was valued at 21–23 billion KRW ($15.9M to $17.4M), depending on the source . Earlier reporting from Battery Power Online cited approximately $13.7M . Cumulative investment reached 65.2 billion KRW ($49M) post-Series C .
• Production facility: Solivis operates a 42-ton/year plant in Hoengseong, Gangwon Province, which began full-scale production in late 2025. The company has secured land for a second factory that will be approximately 10 times larger .
• IPO plans: Solivis plans a KOSDAQ IPO by 2027 and has already supplied samples to leading battery and automaker companies in South Korea and Japan .
• Technology: The company uses a proprietary third-generation wet synthesis process to achieve high ionic conductivity, aiming to become the world's top solid-electrolyte provider by 2030 .

ASSB Applications Expanding Beyond Automotive

TrendForce specifically notes that ASSB suppliers are accelerating automotive testing while simultaneously broadening into new frontiers . These emerging applications include:

• Drones and eVTOLs: High energy density and safety make ASSBs attractive for aerial mobility.
• Microelectronics: Miniaturized solid-state cells for wearables and IoT devices.
• Construction machinery: Heavy equipment electrification where thermal stability is critical.
• Embodied robots: Humanoid and industrial robots requiring high-cycle-life, high-density power.
• Companies with emerging orders: TrendForce's report references Maxell, Ilika, ProLogium, and Factorial among those securing development agreements and early customer traction in non-automotive verticals .

Note: The specific user-requested lithium sulfide price of $219/kg and the global installed capacity figure exceeding 600 metric tons were not found in the publicly available sourced results. These numbers may appear in detailed paid analyst reports from firms like TrendForce or Shanghai Metals Market.