HyDry: RWTH Chair researches new drying process for lithium-ion batteries

The Chair "Production Engineering of E-Mobility Components" (PEM) at RWTH Aachen is working on a novel hybrid drying process for the production of lithium-ion batteries, fuel cells, and electrolyzers in the research project HyDry.

The goal of the project, funded by the Federal Ministry for Economic Affairs and Climate Action (BMWK) for two years, is more efficient drying with less energy consumption.

According to the researchers, the drying process involves removing solvents from the liquid electrode or catalyst coating - a crucial manufacturing step. At the same time, however, it represents a technological bottleneck in the production of batteries, fuel cells, and electrolyzers.

More efficient drying with less energy consumption

In convection drying systems, hot air is obtained through a burner system from fossil energy or in the form of infrared radiation, according to RWTH.

"A major drawback, however, lies in low drying rates and high energy losses," explains PEM director Professor Achim Kampker.

In current systems, drying sections with a length of 40 to 80 meters are necessary, which in turn involves high investment and operating costs.

"We are therefore working on a promising method that enables significantly more efficient drying and reduces energy consumption," says Kampker.

Reusing Thermal Energy

As a research partner, the company Lambda Technology, based in Grafing near Munich, is involved. A hybrid drying process is to be developed, which combines convection and "Near Infrared" (NIR) and can reuse the thermal energy of the exhaust air and NIR radiation.

This would allow for an energy demand approximately 30 percent lower and an energy effort 70 percent reduced compared to previous convection drying systems, compared to pure infrared boosters.

Quality Assurance Procedures

As part of the joint project, the PEM Chair is researching an automatic quality assurance procedure for this new drying method.

Additionally, a test stand is to be developed for experiments, with which researchers can determine suitable operating strategies for the new process during the two-year project phase.