EV batteries get performance boost as nonwoven envelopes tackle heat issues

German company Freudenberg Sealing Technologies is driving innovation in the electric vehicle (EV) industry with advancements in battery technology aimed at enhancing safety, performance, and longevity.

The company’s latest steps include the development of new battery cell envelopes and the creation of custom-designed cell caps, both of which contribute to improved battery performance and safety.

The battery cell envelopes use nonwoven materials to wrap the cell stack, providing protection and electrical insulation during assembly. These envelopes feature a fiber network with a uniform pore structure.

The fibers are treated to stay wet by the electrolyte, reducing gas bubble trapping and maintaining moisture in the cell stack.

New material boosts heat management

Nonwoven materials filled with electrolytes also improve heat management due to better thermal conductivity compared to traditional foils. It also tackles key challenges in battery technology by adding an extra electrolyte reservoir.

Thicker nonwoven envelopes used as in-cell compression elements can absorb much of the cell stack’s growth, allowing for thinner compression layers between cells. This absorption leads to a more even load distribution on the cell stack, which helps reduce the risk of dendrite formation and lithium plating.

Additionally, Freudenberg has developed custom-designed cell caps in collaboration with cell manufacturers. These caps integrate crucial features, such as rupture disks for gas dissipation in case of thermal runaway. Additionally, the cell caps provide excellent mechanical resistance to peak loads and fatigue.

According to Giulia Richard, Global Marketing Director at Freudenberg Sealing Technologies, the company combines “state-of-the-art materials with intelligent design,” merging expertise in sealing technology, engineering plastics, and stamping technology.

“This allows us to set new standards to ensure perfect sealing and a long cycle life for the cell caps,” Richard added.

Long-term gas-tight performance and mechanical resistance

The cell caps are designed to be gas-tight for the battery’s entire lifespan, ensuring reliable performance in different conditions. They also offer good mechanical resistance and work well with various electrolytes and coolants.

For Ulrich Huth, President of Automotive Sales at Freudenberg Sealing Technologies, staying ahead of the curve in the evolving mobility sector is crucial.

“As the market leader in the technology, quality and service segments for the automotive sector, we have all the expertise necessary to develop and manufacture innovative and leading-edge products for the mobility of the future,” Huth explained.

Furthermore, Freudenberg Sealing Technologies claims that these innovations mark significant advancements in EV battery technology.

By improving key aspects such as safety, performance, and longevity, these developments have the potential to enhance the overall efficiency and reliability of electric vehicles, setting new standards for the industry, the company noted.