Research on safe solid-state batteries

Solid-state batteries can boost electric mobility. Within the new application-oriented ALANO project coordinated by BMW AG, industry and scientific partners are studying next-generation lithium batteries: a lithium metal anode and a solid electrolyte provide high safety and improve energy density at the cell level, extending the range of electrical cars. The Helmholtz Institute Ulm (HIU), founded by the Karlsruhe Institute of Technology (KIT) and Ulm University, is involved in the project funded by the Federal Ministry of Research.

Light and powerful, cheap and safe – batteries for electric cars have to meet different criteria. Battery researchers and car manufacturers have therefore been focusing on solid-state batteries for some time now. In such batteries, both the electrodes and the electrolyte are made of solid materials. The solid electrolyte in particular promises to increase safety: it is hardly flammable and cannot leak. The new collaborative project ALANO (stands for: Alternative Anode Concepts for Safe Solid-state Batteries) is about next-generation lithium batteries and focuses on the lithium metal anode as the central component. ALANO aims to improve the energy density of a solid-state battery with high safety.

Higher Energy Density – Greater Range

“Using lithium metal as an anode material can significantly increase the energy density at the cell level and thus extend the range of electric cars,” said Professor Stefano Passerini, director of the Helmholtz Institute Ulm (HIU), one of ALANO’s partners, and head of the group electrochemistry for batteries. Within the ALANO project, research and industry partners are evaluating several innovative lithium metal-based anode concepts for solid-state batteries to optimize the anode’s reactivity, safety and performance and integrate it into a robust, high-energy-density cell unit. Combination with a solid electrolyte is of decisive importance. Unlike conventional liquid electrolytes that react strongly with lithium metal, solid electrolytes are less reactive and therefore allow the formation of kinetically stable interfaces. This promises to bring several benefits: “Firstly, safety will be greatly improved, because the cells will not contain liquid and easily flammable substances,” says Dr. Dominic Bresser, head of HIU’s Electrochemical Energy Storage Materials Group. “Second, the robustness of the cells is increased, which facilitates handling, cooling and system integration.” In this way, costs are reduced at the cell, module and system level. At the same time, the durability of the cells is increased, improving their durability.

Research and development along the value added chain

The ALANO project covers the entire value-added chain of solid-state batteries with a lithium metal anode: from material selection, to component fabrication, to cell manufacturing, to scaling up batteries for use in vehicles and other applications, to recycling. Therefore, aspects of the circular economy will also be taken into account. In the ALANO project, partners from industry and research work together across industries and disciplines.

The consortium is coordinated by BMW AG. Other industrial partners are Applied Materials GmbH, ARLANXEO GmbH, DAIKIN Chemical Europe GmbH, RENA Technologies GmbH and VARTA Microbattery GmbH. Research partners include HIU, Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM, Fraunhofer Institute for Surface Engineering and Thin Films IST, Forschungszentrum Jülich (FZJ), Electrochemical Energy Technology Battery Research Center (MEET) at the University of Münster, Center for Solar Energy and hydrogen research Baden-Württemberg (ZSW), and the University of Gießen. BASF SE is an associated project partner. ALANO will start in September 2021 and will run for three years. The Federal Ministry of Education and Research (BMBF) will fund ALANO under the “Battery 2020 Transfer” program (battery materials for future electromobile, stationary and other industrially relevant applications).