70% less energy in cell production
Less space and energy requirements, but better performance and the highest battery cell quality – that is the approach taken by engineering companies Dürr and GROB for their new concept factory for lithium-ion battery cells.
At this year’s “The Battery Show India” trade fair in Greater Noida, the two partners will be showcasing the technical innovations that make this possible. Key technologies include dry coating of the electrodes, requiring no drying process, and powerful Z-folder technology for cell assembly with integrated notching.
The two global companies Dürr and GROB have been cooperating in the field of production technology for lithium-ion batteries since 2022. The aim is to jointly establish themselves as system suppliers of battery production equipment in Europe, North America and India. By localising technology and building strong partnerships with battery manufacturers in India, the partners aim to contribute to the creation of a robust and self-reliant ecosystem for battery production, supporting the national ‘Atmanirbhar Bharat’ mission.
“We are driving India’s clean mobility transition with world-class manufacturing systems for lithium-ion batteries that combine international engineering excellence with local manufacturing and service throughout the entire project and product life cycle,” says Aji Philip, Head of LiB at Dürr India.
“With our expanded portfolio of highly available machines and systems, we jointly cover almost the entire value chain for battery cell production with our own technologies,” adds German Wankmiller, CEO of the GROB Group.
In addition to a classic production layout with wet coating, the partners have developed a concept factory with dry coating and the new Z-folder technology that represents the next generation of battery cell production. Thanks to powerful and innovative technologies, production requires 50 percent less space and 70 percent less energy, resulting in significantly higher space efficiency & lower operating costs.
Efficient and sustainable dry coating
Dürr’s dry coating system X.Cellify DC implements the so called “Activated Dry Electrode®“ process from development partner LiCAP Technologies. The Dürr machine uses a dry-mixed active material instead of conventional slurry. This powder mixture is pressed into a free-standing film using calender machines, which is then laminated onto both sides of the collector foil.
Compared to wet coating, this eliminates the drying process as well as the recovery and treatment of solvents – saving space, energy, and costs. The free-standing film also offers advantages in terms of material efficiency, as excess film material can be completely returned to the production process before lamination onto the collector foil.
The recently achieved successful proof of concept demonstrates that the Dürr machine is capable of performing the dry coating process with consistently high quality. It can be scaled up, and Dürr is actively seeking pilot partners in the industry.
High-speed cell assembly
With the new generation of Z-folders, which integrate the notching process, GROB achieves higher performance with less space. For particularly stable and reliable system technology, the separator is guided over a few deflection rollers with very even and low web tension. Thanks to a high-quality magazine buffer system for the electrodes, the system achieves 95 percent availability.
Precise electrolyte filling with high pressure
A process developed by Dürr enables battery cells to be filled in a single step without residual gas. Unlike the conventional process, the electrolyte is filled directly into the cells at up to 30 bar. The filling pressure is thus two to three times higher than the current industry standard. The process design enables precise dosing and shortens both the filling process and the subsequent penetration of the electrolyte into the active material.
End-to-end digitalization
The equipment technology from Dürr and GROB is complemented by end-to-end digital mapping of the production process. Even in the planning phase before production starts, a digital twin enables simulation of the entire factory and speeds up implementation on site. The data from the simulation flows into the MES/MOM software of Dürr’s subsidiary iTAC, which can be used to control and plan all production steps in battery manufacturing. Important functions here are traceability and quality analysis to avoid errors in production. This results in high overall equipment effectiveness.
Sustainable production with integrated wet coating solutions
Dürr is a unique partner in offering electrode manufacturing turnkey solutions including coating, drying, solvent recovery, distillation, and calendering. This capability enables optimisation of the overall equipment setup in terms of energy efficiency and footprint.
For classic wet coating, Dürr offers the simultaneous two-sided coating product family X.Cellify SC – a unique process that provides benefits such as a smaller overall manufacturing footprint and no edge curl after drying. It is characterised by a straight-path product flow and a single coating station. A slot-die coating on a backing roll is immediately followed by a tensioned-web slot-die coating to coat both sides of the foil in one pass.
An air flotation dryer enables simultaneous two-sided coating as the foil is running through a non-contact drying process. In solvent recovery, Dürr uses its condenser and concentrator system known for consistently achieving the lowest emission limits of less than 1mg NMP/Nm³ at market leading operational cost and energy efficiency, setting the benchmark for sustainable production.
After drying, the electrode coating is densified using calendering machines. The machines from Dürr work with particular precision using “Dynamic Gap Control”: two sensors measure the distance between the two rollers with an accuracy of 0.5 µm. This results in a very uniform layer thickness, with no more force being applied than necessary. Dürr’s calenders are used for both wet coating and dry coating to compress the film.
At the Battery Show India 2025 from October 30 to November 1, Dürr and GROB presented their concept factory and technological highlights at their joint booth B344 at the India Expo Mart & Centre of Greater Noida.
Dürr introduced a new naming concept. The company is bringing together its products for electrode coating and electrolyte filling under the new name “X.Cellify.”
