Lithium-ion batteries (LIB) are indispensable key components for electro mobility and the success of the energy transition. They offer high energy density and high cycle stability. 8 partners from industry and science are developing technologies and components in the funded project "revoLect" (funding code: 03ETE041) in order to be able to produce resource-saving and more efficient LIBs. The project is pursuing 2 key innovations: the replacement of the usual metal foils with a metallized fabric structure and the use of silicon as anode material.
In the project, novel electrodes with lightweight fabric-based current collectors are being developed for lithium-ion batteries using a resource-saving technology. This technology requires less use of primary raw materials such as copper and aluminum compared to previous lithium-ion batteries. At the same time, this technology enables higher energy densities and thus further material savings from the cell to the system level. Another development focus is the use of pure silicon as anode material in combination with the lightweight fabric structure of the electrodes.
Project partner Porcher Industries Germany GmbH, Erbach/Germany, is a specialist in the production of glass fabrics from glass filament yarns. In the revoLect project, Porcher is developing ultra-light glass fabrics as the basis for electricity collectors. The aim here is to produce ultralight fabrics from the finest glass filament yarns. In parallel, the Institute for Textile Machinery and High-Performance Textile Materials Technology (ITM) at TU Dresden/Germany, is developing ultra-light carbon fabrics based on a carbon spreading technology for the highly efficient electrodes.
The developed carbon and glass fabrics are metallized by elfolion GmbH, Quedlinburg/Germany, by vacuum processes for use as current collectors. The current collector strip material is provided for the production of composite electrodes. elfolion itself is aiming at the realization of a cell cathode, consisting of fractal porous solid structures, which are the active component of the electrode. Compared to the state of the art, the open-mesh and lightweight structure of the fabrics and the porous coating lead to significantly reduced material usage and larger active surfaces. This increases the energy density of battery cells significantly in terms of both mass and volume.
The RWTH Aachen University, Chair of Production Engineering of E-Mobility Components (PEM), is developing processes for coating the fabric-based current collectors with slurry-based electrode materials. Among other things, the pilot plant for cell production is being adapted to process the novel materials. In addition, it is investigating the design and production of the battery cells based on the components provided by the project partners.
The goal of Fraunhofer FEP, Dresden/Germany, in the revoLect project is to develop a process for depositing silicon on the fabric structures.
The partner Customcells Itzehoe GmbH, Itzehoe/Germany, coats the novel substrates with electrode paste under industry-standard conditions. Subsequently, the performance of the batteries is tested by electrochemical measurements.
The Institute for Experimental Physics at the Technical University of Freiberg/Germany is involved in the characterization of the processed individual components and button and pouch cells. From this, microstructure-property correlations as well as design proposals and processing parameters will be derived for the cooperation partners.
Romonta GmbH, Seegebiet Mansfeld/Germany, interconnects the manufactured cells to battery systems and carries out final practice-related application tests. In the evaluation, cell parameters such as aging and current/voltage resistance are to be analyzed and transferred to the mobile application. This will ensure the powerful performance of the LIB.
Lithium-ion batteries with significantly increased energy density and lower material consumption compared to the state of the art: this is the ambition of the project consortium. All partners in the revoLect project will be working at full speed over the next 3 years on application-oriented development along the entire process chain for the production of highly efficient lithium-ion batteries.