LG Chem and LX Hausys have developed a ‘Special Flame Retardant Continuous Fiber Thermoplastic (Special Flame Retardant CFT)’ that is reported to withstand a flame at 1,500 degrees Celsius for over 20 minutes, delaying battery thermal runaway. (Photo courtesy LG Chem)

LG Chem and LX-Hausys worked together to develop the continuous fiber thermoplastic material.

SEOUL, South Korea—LG Chem, together with LX Hausys, have reportedly developed a material that can delay battery thermal runaway by withstanding a flame at 1,500°C for more than 20 minutes.

The material, named “Special Flame Retardant Continuous Fiber Thermoplastic (Special Flame Retardant CFT)” is capable of withstanding strong flames and high pressure for more than 14 times longer than existing thermoplastics, LG Chem said in a release.

The thermal runaway phenomenon, long a pain point for electric vehicle (EV) and battery customers, is one of the factors that have delayed the popularization of EVs. LG Chem and LX Hausys have reportedly resolved the heat and pressure associated with thermal runaway— which was difficult to withstand with existing plastics—through their development of the Special Flame Retardant CFT.

LG Chem said it used a torch test subjecting the 1.6mm-thin Special Flame Retardant CFT to temperatures exceeding 1,500°C and pressure. The material did not melt, run down, or develop any holes, even after 20 minutes, achieving what the company called “the industry’s highest level of flame blocking performance.”

The Special Flame Retardant CFT incorporates LG Chem’s super flame barrier material technology and LX Hausys’ Continuous Fiber Thermoplastics (CFT) manufacturing technology. The super flame barrier material developed by LG Chem last year had the capacity to withstand flames at temperatures exceeding 1,000°C for over 10 minutes—reportedly the longest duration in the world at the time. LX Hausys improved the performance of the LG Chem material by applying manufacturing technology that layers in the form of tape, according to LG Chem.

Because the Special Flame Retardant CFT is solid and has low deformation under force (high rigidity), it can be used in the top and bottom covers of large battery packs among electric vehicle battery components. LG Chem expects that it will effectively delay the spread of flames in the event of an electric vehicle fire, helping to secure the time required for driver evacuation and fire suppression.

Last year, LG Chem completed the development of super flame barrier materials and established a mass production system. Super flame barrier materials can be molded with precision and are primarily used in battery modules. The Special Flame Retardant CFT developed this year is used for the large battery pack cover that encases the module. Using both materials together can provide a double barrier against the spread of flames, the company said.

“We have been working closely with LX Hausys since we developed and announced a super flame barrier material last year,” said Tom Shin, LG Chem’s head of marketing department, engineering materials, in the release. “We are proud to have a total solution lineup [including super flame barrier, glass fabric laminated thermoplastics, and continuous fiber composite (UD-tape)] for electric vehicle thermal runaway. We will continue research and development to make the daily lives of electric vehicle drivers safer while addressing customer pain points.”