Germany-headquartered Freudenberg Sealing Technologies has introduced cell caps and nonwoven cell stack envelopes for prismatic battery cells.

The battery cell envelopes use nonwoven materials that wrap the cell stack and, like conventional films, protect it during the assembly and provide electrical insulation. Nonwoven envelopes consist of a fiber network forming an ultra-homogeneous pore structure. The fibers are surface-treated for permanent electrolyte wettability to reduce the risk of entrapping gas bubbles as the cell is filled, and to help to keep the cell stack wetted over its lifetime.

Nonwoven materials filled with electrolyte also offer improved heat management within the cell compared to conventional foils, owing to the resulting higher thermal conductivity, according to the company.

The custom-designed cell caps, developed in collaboration with cell manufacturers, are tested to be gas-tight and to maintain this capacity throughout the battery’s cycle life. This optimizes performance in a range of operating conditions, minimizes the risk of gas leakage and increases safety. The cell caps also have strong mechanical resistance to peak loads and fatigue. They are compatible with various electrolytes, coolants and gases, enabling integration into different EV systems.

“In these customer projects, we combine state-of-the-art materials with intelligent design and merge our expertise in sealing technology and engineering plastics with our knowledge of stamping technology to ensure perfect sealing and a long cycle life for the cell caps,” says Giulia Richard, Global Marketing Director at Freudenberg Sealing Technologies.

Source: Freudenberg Sealing Technologies