Dry rooms for powerful batteries

The dry room systems from Weiss Technik ensure the highest quality in the manufacturing of lithium-ion batteries. The equipment manufacturer offers customized and energy-efficient solutions that are turnkey integrated into the building. In aftersales, Weiss Technik supports customers with comprehensive service.

The production of lithium-ion batteries requires an extremely dry environment. Lithium reacts very strongly to humidity. Even at low moisture levels, it oxidizes, significantly reducing the battery's capacity and performance. Therefore, the production of battery cells takes place in dry rooms where humidity is minimized and dew points reach as low as -70 degrees Celsius.

Customized complete solutions

The planning of a dry room system is a highly complex task. Even the slightest changes in humidity—such as employees speaking or sweating—can impair the quality of the battery cells.

As one of the leading companies in environmental simulation, Weiss Technik benefits from decades of experience in creating precisely defined climatic conditions. Weiss Technik's dry room systems dehumidify the air to a residual moisture content of up to 0.0016 grams per kilogram of air. This corresponds to a dew point of -70 degrees Celsius. Weiss Technik designs the systems individually for the customer's processes and integrates them turnkey into the building structure. The focus is on energy-efficient room drying.

Combined dehumidification measures

To ensure the required dry process atmosphere, the dry rooms are airtight separated from the surrounding production building. Inside, a slight positive pressure exists, protecting the chamber from the ingress of moist outside air.

The drying process itself occurs through two dehumidification methods: condensation dehumidification as a pre-stage and adsorption dehumidification. Condensation corresponds to conventional dehumidification by cooling. Weiss Technik's dry room systems initially cool the fresh air in the production area, causing much of the moisture to condense. In the second stage, specially coated drying wheels remove the residual moisture based on the principle of adsorption dehumidification. The air in the production area is continuously dehumidified by circulating it over the dehumidification rotor in a recirculation process.

High efficiency through adsorption dehumidification

Adsorption dehumidification is among the most efficient systems on the market. It allows for a continuous dehumidification process with dew points down to -70 degrees Celsius. Specially coated drying wheels extract moisture from the room air down to the target value. The air to be dried flows through a layer of fleece material, which has a structure made of bound silica gel and metal silicates, and is dehumidified to the required dew point temperature. An adsorption wheel absorbs the extracted moisture. In counterflow, the moisture absorbed in the silica gel is expelled using hot regeneration air.

System sizing for each dry room

Manufacturing lithium-ion batteries typically takes place in individual rooms with different dry room conditions. These rooms require specific dew points and purity levels. They are also exposed to various influences, such as present personnel or equipment. Generating the necessary extremely dry process atmosphere can also consume up to 40% of the energy required for battery production.

Determining the requirements for each dry room and the system sizing are core competencies of Weiss Technik. The equipment manufacturer implements dry room systems that consider all factors and feature high energy efficiency.

Application-specific configured dry room systems

Experience shows that standard products for room drying often do not meet the complex requirements. Unlike common market offerings, Weiss Technik designs and builds its dry room systems individually for each process and drying chamber. Weiss's air dehumidification systems are "tailor-made" and optimized. This way, Weiss Technik achieves effective and energy-saving drying processes.

Turnkey system integration of complete solutions

Weiss Technik distinguishes itself from competitors through another significant feature: the company specializes in integrating climate chambers into existing and new building structures. The equipment manufacturer has the planning and solution expertise to realize dry room projects from A to Z as a single source. The focus is on the equipment used, the proper supply of the chambers, and integration into the customer's plant and safety concept.

For new construction projects for battery cell manufacturing, Weiss Technik supplies both the dehumidification technology and the architecture of the dry room. The company's extraordinarily broad range of services includes complete solutions for dry room technology as well as ventilation, air purification, and dehumidification techniques tailored to specific climate requirements. New systems can thus be realized at optimal costs. Weiss Technik handles the entire plant construction—from planning through implementation to commissioning. During the preliminary project phase, engineers support the customer with competent advice and high responsiveness.

Comprehensive aftersales support package

After commissioning, Weiss Technik provides its customers with a nationwide service network as a responsive and competent partner. The service hotline is available around the clock. The central warehouse delivers overnight, and in urgent cases, well-trained and experienced service technicians are on-site within 24 hours. Spare parts for installed systems are available long-term.

The service catalog ranges from regular maintenance and calibrations to leak and safety inspections, as well as retrofitting of the system. For maintenance of the dry room system, Weiss Technik offers tiered options with basic, premium, and full maintenance packages.

From practice:

Current dry room projects for industry and research

Battery manufacturing in the automotive industry

Weiss Technik is implementing a comprehensive dry room turnkey solution including system integration for an automotive manufacturer.

The automaker awarded Weiss Technik the contract for the drying technology in a new pilot plant for lithium-ion battery production. The completion of the dry room system is scheduled for the end of 2022. This follows successful collaboration in 2019 on the delivery of a dry room for a research facility.

Weiss Technik is constructing ten individual rooms covering approximately 3,000 m², with some differing dry room conditions. The climate control of the rooms is separate and autonomous to achieve the most energy-efficient and economical production possible.

Weiss Technik designs and supplies the dry room and climate technology, including adsorption dryers, climate control, as well as cell and steel construction, including walls, ceilings, airlocks, ducts, and piping. The system is designed for maximum energy efficiency, visibly improving the well-to-wheel balance of the production process. After completion, Weiss Technik will maintain the system through regular maintenance and service work.

Complete system for battery research

Another individually configured dry room system for the development and production of lithium-ion batteries is currently being built by Weiss Technik in Norway. The client is a large Scandinavian research organization.

In a newly established competence center, they aim to research and develop lithium-ion batteries for future electric drives. Weiss Technik designs and supplies the cell construction as well as the demand-oriented air dehumidification technology for the approximately 155 m² dry room. The customer's target is a constant room dew point temperature of -42.5 degrees Celsius with maximum energy efficiency. The system is expected to be operational by mid-2022.