New Electrolyte Technology from CUHK Solves Lithium-Ion Battery Safety Issues

From rechargeable batteries in portable electronic devices to power sources for electric bicycles and new energy vehicles, safety accidents caused by lithium-ion battery fires and combustion have increasingly become the focus of global attention. According to a report by CNN on the 22nd, a new technology developed by a research team from The Chinese University of Hong Kong (CUHK) can significantly reduce the risk of lithium-ion battery explosions and fires, and this technology is expected to be commercially applied within the next 3 to 5 years. 

The report points out that lithium-ion batteries have been widely used in various devices ranging from smartphones to new energy vehicles. Researchers stated that lithium-ion batteries have good safety under normal usage scenarios, but improper use may lead to fire hazards and even fatal consequences in extreme cases. The reason is that the electrolyte filled inside lithium-ion batteries is flammable. When subjected to physical puncture, overcharging, extreme temperature and humidity conditions, or production process defects, the batteries will gradually lose stability. Once an abnormality occurs, the battery temperature will rise rapidly and ignite the electrolyte, thereby triggering a dangerous chain reaction known as "thermal runaway". Relevant statistical data shows that in 2024 alone, 89 battery-related smoke, fire or high-temperature abnormal incidents were recorded in the global civil aviation transportation sector; in daily life, battery fire accidents of electric bicycles, electric scooters and other devices are also not uncommon. 

To address this safety pain point, the global scientific research community has actively carried out technological research, such as developing high-temperature resistant solid or gel electrolytes to replace traditional liquid electrolytes. However, such solutions require large-scale modifications to existing battery production lines, which significantly raises the industrialization threshold and limits the popularization speed of the technology. In contrast, the new lithium-ion battery optimization scheme proposed by the CUHK team only needs to replace the chemical components in the existing electrolyte without altering the core links of the production process. 

Researchers from the team explained that the core cause of lithium-ion battery fires is the decomposition of the electrolyte under high pressure, which releases a large amount of heat and triggers a chain reaction. The newly developed electrolyte adopts a binary solvent system, which can accurately block this dangerous reaction process. Under normal temperature conditions, the first solvent can maintain the compactness of the internal chemical structure of the battery, ensuring the normal performance output of the battery; when the battery temperature rises abnormally, the second solvent will quickly activate the protection mechanism, preventing fire risks from the source by loosening the chemical structure and slowing down the reactions related to thermal runaway. 

CNN cited laboratory test data showing that after the lithium-ion battery adopting this new technology was punctured by a nail, the temperature only rose by 3.5 degrees Celsius; in contrast, the temperature of traditional lithium-ion batteries soared to 555 degrees Celsius under the same test conditions. Researchers emphasized that this technical scheme will not have a negative impact on the core performance and service life of the battery. Tests have shown that after 1000 charge-discharge cycles, the battery capacity can still maintain more than 80% of the initial value, fully meeting the requirements of commercial application. 

It is worth noting that since this technology only involves the replacement of electrolyte components without the need to modify existing production lines, it has the basic conditions for rapid industrialization. It is estimated that after large-scale production, the cost of lithium-ion batteries adopting this technology will be basically the same as that of current mainstream products. At present, the relevant technology has entered the stage of commercialization advancement. Donald Finnegan, a senior scientist at the U.S. National Renewable Energy Laboratory, commented: "This technological breakthrough is exciting, meaning that future lithium-ion batteries will be able to withstand extreme working conditions such as high temperatures and short circuits, fundamentally avoiding fire risks."