Aerogel for EV Battery Thermal Runaway Barriers: What to Check Before You Buy
For an EV battery thermal barrier, the spec most buyers lead with is the wrong one. Thermal conductivity tells you how well a material insulates in normal service. A runaway barrier has a different job: survive a cell venting at 600°C or more, and hold the heat back long enough to keep the fire from reaching the next cell. That is a test of maximum temperature and physical integrity, not of a room-temperature λ figure.
AerogelHub lists 19 suppliers that tag EV battery as an application, with published maximum temperatures from 500°C to 1600°C. Here is what separates a barrier from ordinary insulation, and how to shortlist on it.
What a runaway barrier does
When a lithium cell goes into thermal runaway, it vents gas and heat in seconds, and the surface can pass 600°C, sometimes far higher. A barrier between cells or modules does two things at once: it takes that heat without breaking down, and it slows the heat reaching the neighbor long enough for the pack to survive.
Aerogel fits the role because it stays intact at high temperature and conducts heat slowly. Those are two separate properties, rated by two separate numbers. Only one of them tends to appear on a marketing sheet.
Maximum temperature is the gating spec
Check the temperature rating first. Among the 19 EV-battery suppliers in the directory, the published maximums spread wide: Guangdong Alison at 500°C, a cluster at 650°C, up through Xiamen Namate at 1200°C and JIOS Aerogel at 1600°C.
That spread is the decision. A 650°C barrier and a 1600°C barrier survive different events. Do not read the gap between them as a price tier. Match the rating to the worst-case venting temperature of your cell chemistry, then compare what is left.
Thermal conductivity still counts, second
Once a barrier survives the event, its conductivity decides how much heat reaches the next cell in the seconds that matter. So you want both: a temperature rating high enough to survive, and a λ low enough to delay.
The mistake is shortlisting on the λ headline alone, the way you would for pipe lagging or a building wall. A low room-temperature λ on a material that degrades at 500°C is a number that stops mattering the moment it is needed.
The demand behind this is real
This is not a hypothetical application. In January 2026, JIOS Aerogel’s Korean manufacturing licensee won a Hyundai Motor Group tender to supply Thermal Blade runaway barriers for Hyundai and Kia models, with mass production scheduled for June 2027. Two months later, LG Chem showed its Nexula aerogel barrier at InterBattery 2026, pitched for cell-to-cell, module-to-module and pack-level use. Regulators are pushing the same direction, with no-propagation requirements tightening across major EV markets. The supplier base is widening to match, which is why a directory that separates the serious barrier makers from general insulation vendors earns its keep here.
How to shortlist
- Filter to EV battery, then to temperature. In the directory, narrow to EV battery suppliers, then to a maximum temperature at or above your cell’s worst case.
- Ask how the barrier is tested. A propagation or torch test on a real pack tells you more than a λ figure from a guarded hot plate. That is a number measured under conditions close to a runaway.
- Treat a blank rating as a question. Several suppliers that serve this market, Aspen and Enersens among them, have a max-temperature rating we have not sourced yet. A blank cell means we have not sourced it, not that the barrier cannot take the heat. Ask.
The right barrier is the one that survives your worst case and delays the rest. That is a temperature decision first, a conductivity decision second, and never a headline-number decision.
Ready to shortlist? Filter the directory to EV battery suppliers by temperature, then line up your finalists in the table.