Why Is Aerogel Used as EV Insulation in Battery Packs?
Without an effective thermal barrier between EV battery cells, heat from a failing cell can reach neighboring cells and increase the risk of thermal propagation.
Aerogel is increasingly used as EV insulation because it can provide high thermal resistance in a thin, lightweight barrier. In battery packs, engineered aerogel pads can be positioned between pouch or prismatic cells and designed around compression, cell swelling and thermal runaway requirements.
Where Is Aerogel Insulation Used in an EV Battery?
Placing insulation in the wrong location can add cost and thickness without controlling the most important heat-transfer path.
One important application is the cell-to-cell interface. Aerogel thermal barriers can separate adjacent cells, while other pack areas may require different insulation, electrical isolation or fire-protection materials.
Location
Main Requirement
Aerogel Role
Cell-to-Cell
Limit heat transfer
Thermal propagation barrier
Module
Thermal separation
Thin insulation layer
Pack
System-level protection
Application-specific barrier
Why Is Aerogel Useful During Battery Thermal Runaway?
Thermal runaway is not ordinary operating heat; it can involve intense heat, flame, pressure and ejected particles.
Aerogel helps reduce heat transfer from the affected cell toward adjacent cells. Automotive aerogel barriers are therefore engineered as part of a broader thermal propagation strategy rather than as a material that makes thermal runaway impossible.[1]
UL Solutions also emphasizes that thermal runaway material evaluation must consider combined thermal and mechanical hazards, not simply conventional flammability.[2]
How Should EV Engineers Select Aerogel Insulation?
Choosing aerogel only by thermal conductivity can result in poor fit, excessive compression or insufficient protection after battery aging.
Evaluate thickness, thermal performance, compression response, cell chemistry, swelling, pack geometry and validation requirements together. Automotive aerogel barriers can be engineered around thickness and mechanical response for specific cell architectures.[3]
Developing an EV Battery Thermal Barrier?
Send Fuqiang your cell format, available gap, target thickness, compression requirement and battery pack drawing. Our team can review aerogel insulation options and sample requirements for your EV battery project.
FAQ
Is aerogel used in electric car batteries?
Yes. Engineered aerogel thermal barriers are used in EV battery applications, particularly between cells where thin thermal insulation and propagation control are important.
Can aerogel stop battery thermal runaway?
Aerogel does not prevent the electrochemical failure inside the initiating cell. Its role is to reduce heat transfer and help delay or prevent propagation to neighboring cells when properly engineered and validated.
How thick is EV battery aerogel insulation?
There is no universal thickness. Cell geometry, chemistry, compression, thermal targets and available pack space determine the final design.
Is aerogel suitable for 800V EV battery packs?
It can be part of an 800V battery thermal-protection system, but voltage level alone does not determine aerogel selection. Electrical insulation and system-level HV requirements must also be validated.
After 15 years in automotive wire harness and EV component projects, I treat aerogel as part of the complete battery-pack safety architecture. The right material must work with cell spacing, HV insulation, wiring, busbars, compression and thermal runaway strategy—not against them.