Freudenberg Sealing offers material testing for lithium-ion batteries

Plymouth, Michigan – Freudenberg Sealing Technologies has expanded its material testing capabilities to include performance and compatibility evaluations of the rubber, elastomer and thermoplastic materials used to seal lithium-ion batteries. 

The company has installed “sophisticated equipment” and adopted new testing protocols in its central laboratory in Plymouth, Michigan, in order to provide “conclusive data” on which materials optimally resist breakdown from constant exposure to harsh electrolytic solutions. 

Such data has not been readily available in the private sector until now, FST said in a 16 March statement.

At the heart of the six-digit investment is a “specially-designed” isolation and containment chamber (IsoC) that allows technicians to safely conduct exposure testing using the very aggressive lithium electrolytic solutions found in lithium-ion battery cells. 

The solutions are volatile, toxic and flammable when exposed to oxygen and ambient air moisture. The IsoC, a six-by-three-by-three-foot, two-chambered glass and steel enclosure, allows chemists to work in a controlled, inert and moisture-free environment. 

In addition, FST said it invested in a number of other equipment, including a telemetry control system that facilitates remote IsoC monitoring 24/7; head-to-toe protective gear and special respirators for chemists; non-reactive, nickel-based immersion vessels; and a safety monitoring and alarm system.

“What we can now offer customers is design security based on scientific data,” said Joseph Walker, director research & development for Freudenberg Sealing Technologies in the Americas. 

“We have taken this proactive step on behalf of our customers and in response to a growing use of lithium-ion batteries in diverse applications,” he added

According to Walker, previous efforts were conducted to determine the impact of materials on the electrolyte. The new investment, however, focuses on the impact the electrolyte has on the materials, he added.

Citing multiple analyst forecasts project, FST said it expected that the lithium-ion battery market will experience “double-digit growth” during the next five years.

Demand, it said, will be mostly driven by the increasing use of battery in the automotive, construction agriculture, mining and other transport segments. 

Electrolytic solutions used in lithium-ion batteries have a direct impact on the performance of batteries, but expose seals, gaskets and other components to a constant mix of reactive, flammable, caustic and hazardous chemicals.

“All of our exposure testing must be performed inside the IsoC in an oxygen-free, moisture-free environment,” said Freudenberg Sealing Technologies’ Michael Saruna, the central laboratory chemist in charge of material testing in electrolytic solutions. 

“Electrolytic solution exposed to air can result in a hazardous situation, so we had to take safety and our ability to maintain a controlled environment into account during the design of the IsoC.”

The dual chambers of the IsoC allow Saruna to install test samples in the first chamber, purge all air, oxygen and moisture from that space and then move them to the second, larger IsoC chamber for exposure testing. 

Materials will be immersed in electrolytic solution for at least 1,000 hours, then decontaminated to insure they are safe for removal from the IsoC. They will then be subjected to the company’s standard physical and analytical test methodologies. 

Freudenberg said it will use two electrolytic solutions in its immersion testing – one that is commonly used in lithium-ion battery cells and one that has been manufactured as a control. 

The company will test families of materials, beginning with its own proprietary materials and then moving on to test commercially available materials that are used in these batteries.

“Benchmarking will provide us with the ability to spot gaps in compatibility and performance,” Walker said. “Then we can develop material programs and components to fill those gaps.”