Meaning
High-temperature barrier sheets made from natural sheet silicate minerals offer mechanical stability and thermal resistance during lithium-ion cell thermal runaway. Battery pack designers rely on mica insulation to stop the spread of extreme heat and prevent fire from penetrating the top cover of the pack. This mineral-based sheet withstands direct exposure to jet flames without losing its structure or electrical insulation properties.
It provides a passive barrier that does not degrade under high thermal stress.
Material Properties
Plates or sheets of this material are placed between the module and the top enclosure of the pack. Mica exhibits excellent dielectric strength and remains thermally stable up to one thousand degrees Celsius. This prevents high-voltage electrical tracking while blocking convective heat from venting gases.
Passengers sitting directly above the battery are protected by this setup.
Sourcing Tradeoff
Designers balance the protection offered by this mineral sheet against the added weight and cost of the pack. Procurement teams buy these sheets in pre-cut shapes tailored to the specific pack geometry. Selecting the correct thickness minimizes mass while ensuring safety compliance.
Production Handling
Mica sheets are fragile and require careful handling during module assembly. Automating the placement of these sheets prevents cracking.
