IDTechEx has released a new report that analyses trends in battery design, safety regulations, and their impact on fire protection materials to create a market forecast of the next 10 years. The materials covered include ceramic blankets/sheets, mica, aerogels, coatings, encapsulants, encapsulating foams, compression pads, phase change materials, and several other materials.

Variety in battery design and evolution

Battery designs remain varied, prismatic taking around 55% of the car market in 2021, with the rest split between cylindrical and pouch. Thermal management strategy also varies between manufacturers, with cold plates beneath the cells being the most popular option, but sidewall-cooled and air-cooled batteries also present significant adoption. Many manufacturers are also moving towards a cell-to-pack design where module housings (and a host of other materials) are removed, leading to improved energy density but potentially more challenging thermal runaway propagation prevention. IDTechEx says these design choices greatly impact the choice and deployment of fire protection materials.

Materials applicable for fire protection in EV batteries

IDTechEx says ceramic blankets have been a common choice to provide protection above the cells and below the lid and to delay fire propagation outside the pack. Mica sheets have also been applied to provide fire protection and electrical isolation. The application of Aerogels within EV batteries has largely been limited in volume and constrained to China. However, Aspen Aerogels has secured a supply agreement with GM for its Ultium battery pack, moving the technology to the US. The use of encapsulating foams has also seen significant adoption for cylindrical cell battery packs with companies like Tesla to provide lightweight thermal insulation and structure. For pouch cells, compression pads are commonplace to accommodate cell swelling, and many are now combining this functionality with fire protection to provide a multifunctional solution. IDTechEx predicts a 13-fold increase in yearly demand for fire protection materials in EV batteries by 2033 compared to 2022.

Developments in safety regulations

IDTechEx says China was an early adopter of thermal runaway-specific regulations, with, among other requirements, a need to prevent fire or smoke from exiting the battery pack for 5 minutes after the event occurs. While a formal mandate similar to this is yet to be applied in other regions, OEMs have started targeting this or more stringent requirements in their designs to pre-empt future regulations and improve overall safety.

The organization says the Indian EV market has made a large transition in safety. In 2022, several fires in electric scooters were exhibited, and many recalls were issued. The governing bodies have now set a limit to only using approved cells and battery design features like inter-cell spacing are also stated. IDTechEx’s research shows that the combination of relatively large batteries and huge unit volumes sees electric cars accounting for over 90% of the fire protection materials market for EVs by the end of the decade.