China has introduced a new national standard that clearly defines what qualifies as a solid-state battery, requiring liquid electrolyte content below 5% of total cell weight. The move aims to eliminate misleading marketing claims, strengthen industrial credibility, and accelerate the commercialization of next-generation EV batteries.
China has introduced a new national standard that clearly defines what qualifies as a solid-state battery, requiring liquid electrolyte content below 5% of total cell weight. The move is designed to eliminate misleading marketing claims, strengthen industrial credibility and accelerate the commercialization of next-generation batteries for electric vehicles.
No more exaggerated marketing announcements. Electric vehicle manufacturers must now prove that their battery claims reflect genuine industrial readiness rather than future ambitions. Seeking to reinforce its credibility in international markets, particularly in Europe, China introduced the new regulatory framework on July 1, establishing precise classification rules for automotive batteries.
The goal is to eliminate vague promotional labels surrounding semi-solid-state batteries used in the automotive industry. As reported by CarNewsChina, the new standard is intended to ensure that companies can substantiate claims about the technologies they are bringing to market.
A stricter certification process for solid-state batteries
Until recently, many Chinese automakers and battery manufacturers marketed batteries as solid-state even though they were actually semi-solid-state, still containing significant amounts of liquid electrolyte to improve conductivity. Under the new regulation, product certification has become far more rigorous.
The battery cell is first weighed with high precision before testing begins. It is then placed inside a vacuum chamber and heated to 120°C for six hours. The combination of high temperature and deep vacuum forces any volatile solvent or liquid component, including liquid electrolyte, to evaporate and leave the cell.
The cell is weighed again after the test, and engineers calculate the loss of volatile mass by comparing the initial and final weights. This measurement determines the exact amount of liquid electrolyte originally present inside the cell.
To receive the official solid-state battery designation, the remaining liquid electrolyte must account for less than 5% of the battery cell’s total weight.
From concept to production: Doctex’s Tianjin gigafactory
One of the first practical examples of this new industrial direction is the decision by Doctex, one of China’s leading battery research, development and manufacturing companies, to commission a gigawatt-hour-scale production facility in Tianjin.
The plant represents one of the first large-scale industrial responses to the country’s stricter battery classification rules. Unlike hybrid battery technologies, the Tianjin facility has been designed specifically to manufacture cells capable of passing the new solid-state certification test and verifying that liquid electrolyte content remains below the 5% threshold.
The cells leave the factory already certified and ready for installation in electric vehicles, offering an estimated 15% to 20% increase in driving range.
Dongfeng’s transition strategy
Meanwhile, Chinese automaker Dongfeng Motor is pursuing a diversified technology strategy by developing a transitional battery chemistry that also complies with the country’s new national standards.
Its battery cells combine a ceramic oxide material, valued for its thermal stability and safety, with a polymer component that offers greater flexibility and is easier to manufacture at scale.
Under the new classification system, these cells deliver an energy density of 350 Wh/kg and maintain thermal stability at temperatures of up to 170°C. They fall into the regulated category of hybrid solid-liquid batteries, containing more than 5% but less than 20% liquid electrolyte.
Dongfeng plans to use this transitional chemistry, which is inherently safer and more efficient than conventional liquid-electrolyte batteries, in selected vehicle models. During winter testing, the batteries retained 72% of their original charge while providing a driving range of up to 1,000 km.
The company expects to deploy 100 demonstration vehicles in China’s Hubei Province to collect operational data before expanding commercial production.
