Freudenberg introduces new seal for traction-battery housings

Plymouth, Michigan – Freudenberg Sealing Technologies released a "Profiles-to-Gasket" seal for traction-battery housings, specially developed for production runs of up to 5,000 batteries per year.

Seals designed with the P2G approach supplement those that so far have mainly been designed for high-volume production, according to a company statement. The seal contributes to the more economical production of electric vehicles by protecting high-voltage components from moisture and dirt while allowing good access to all components, according to the statement.

Auto makers have turned to housings with a large cover that allows access, but the dimensions of such seals must be adapted to a specific battery. Freudenberg said changes are impossible without fabricating a new tool. The investment in a tool of this kind repays the expense at higher volumes. Straight sealing profiles come into use for very small production runs, such as the manufacture of prototypes. Their lengths can be cut manually, and can be connected to one another using special corner pieces, making it possible to cover any housing geometry.

"Both concepts have proven themselves in the market, but we deliberately sought another solution for the medium-range volumes that prevail in the market for electric vehicles today," Peter Kritzer, battery expert for Freudenberg Sealing Technologies, said in a statement.

The P2G is based on a principle of achieving the functions of "sealing" and "fixing" in separate parts of the sealing profile. A compressible hollow profile on the outer side of the seal, which can be up to 15 millimetres wide, makes certain that no fluids or particles penetrate into the housing, according to the statement. On the inner side, there is a fixation strip that can attach the seal to the housing. The design makes it possible to manufacture the P2G seal as an endless band and trim it to the required length in each case. With targeted incisions in the attachment area, it is possible to guide the seal in tight radii around corners in both concave and convex shapes. By screwing down the housing and cover, the profile is compressed to a height of about 1.5 millimetres.

Earlier this year, Freudenberg Sealing Technologies received the European patent 2634457 B1 for this product. Freudenberg is now looking into how much the tailoring process can be automated.