heat shield

Due to the growing energy density of battery systems, the developers of lithium ion batteries must satisfy ever higher safety requirements. It is especially crucial to keep a single damaged cell from overheating the entire battery module. Freudenberg Sealing Technologies has developed a innovative heat shields for use in prismatic and pouch cells with almost no impact on the required installation space. It combines the high heat resistance of a silicone-based elastomer with the high insulating properties of air.

The goal is greater range without the battery growing in size and weight: High energy density, which has been battery developers’ top priority, creates a basis for the broad acceptance of electric vehicles. But the more energy is stored in a confined space, the greater the safety requirements. So precautions are essential in case a damaged cell overheats. Experts call the phenomenon “thermal runaway,” and it can cause the temperatures in a cell to rise as high as 600°C. The risk is that the battery’s cooling system would not be able to drain the heat away quickly enough under these conditions. If neighboring healthy cells also heat up due to the heat buildup, a chain reaction can result that, in the worst case, could lead the entire battery system to explode.