New tech aids safe air transport of lithium batteries

A new technology enabling the safe air transport of lithium batteries has been successfully tested in China, a breakthrough expected to facilitate trade as the use of such batteries continues to expand.

Recently, a 250-kilogram power lithium battery was loaded onto a cargo flight at Ezhou Huahu International Airport in Ezhou, Hubei province, and delivered to Shenzhen, Guangdong province, within two hours. The operation improved efficiency by nearly 80 percent compared with traditional land transportation, according to Xiang Xiwen, head of the operational standards department at SF Airlines, a subsidiary of Shenzhen-based logistics company SF Holding, which handled the shipment.

Lithium batteries are widely used in sectors that include electronics, new energy vehicles, robotics and power storage. China is the world's largest producer of power lithium batteries. The total output value of the country's lithium battery industry exceeded 1.2 trillion yuan ($169.7 billion) in 2024, a year-on-year increase of 24 percent, according to data released by the Ministry of Industry and Information Technology. Installed lithium battery capacity rose 48 percent year-on-year to more than 645 gigawatt-hours.

Because of the risk of combustion and explosion, lithium batteries are classified as dangerous goods, making air transport a long-standing safety challenge.

In this trial run, the shipment used an advanced safety protection system. The batteries were placed in a protective case made of specialized materials offering thermal insulation, flame retardancy, pressure reduction, toxin mitigation and fire-suppression functions, said Liu Xingliang, an associate professor at the School of Traffic and Transportation at Chongqing Jiaotong University, which leads the research and development of the technology.

"According to test results, when the batteries caught fire, no open flames escaped from the protective case and its surface temperature remained below 100 C," Liu said. "During the battery explosion tests, the protective case did not warp, the latches stayed tightly closed, and no fragments flew out."

An automatic warning system also monitors 12 core indicators in real time, including temperature, pressure and gas levels inside the protective equipment during transportation. Using artificial intelligence-based early warning algorithms, the system can detect subtle abnormalities such as a minor gas leakage.

"Once abnormalities are detected, the early warning system issues an immediate alert, allowing supervisors to intervene before battery thermal runaway occurs," Liu said.

According to third party testing, the system's average early warning response time is 5.38 seconds, with an accuracy rate exceeding 96 percent, providing "precise, efficient and real-time protection for transportation safety", he said.

The project is part of a key national research and development program under the 14th Five-Year Plan (2021-25) and was approved by the Ministry of Transport and the Ministry of Science and Technology.

"With the growth of companies across China's new energy industrial chain, the potential for air transport of lithium batteries is enormous," said Du Meng, assistant manager of the energy and chemical industry department at SF Holding. Each flight can carry between 5 and 30 metric tons of lithium batteries and related equipment, depending on payload capacity, he said, adding that shipping fees per kilogram vary by destination country and seasonal market conditions.

Currently, more than 90 percent of lithium batteries handled by the company are transported by land or sea, while about 2 to 3 percent of customers ship batteries by air for export.

"Cross-border air transportation of lithium batteries offers an irreplaceable advantage in meeting overseas delivery timelines," Du said, noting that the new technology could help Chinese companies expand into international markets.

China's air transport volume of lithium batteries reached 645,000 tons in 2024, up 21.26 percent year-on-year, with market demand continuing to rise, according to the Civil Aviation Administration of China's dangerous goods transport management center.

Wu Jinzhong, a project leader and professor at Chongqing Jiaotong University, said the technology will be gradually promoted nationwide to advance the standardized and regulated development of power lithium battery transportation.