RealLi!

Realization of optimized Li-Ion batteries for the breakthrough of e-mobility

In order to bring about thorough change in the mobility sector regarding sustainable and effective reduction of greenhouse gas emissions, efficient and safe traction batteries and concepts are needed above all. Future Li-ion battery materials not only have to impress with a significant increase in performance compared to energy storage systems currently available on the market, but also offer a significant reduction in their use of the critical raw material cobalt in the cathode material.

Existing research on nickel-rich layer oxides of the LiNixMnyCozO2 type (NMC622, NMC811) show that these particularly promising cathode materials have higher specific capacities, but suffer from low cycle stability and thermal instability due to the high nickel content.

To counteract this, the RealLi! project demonstrates the cathode material NMC811 with several approaches (coating of the particles and structuring of the electrode bands). Powder coating will stabilize the reaction interface between the electrode and the electrolyte, which improves the longevity and safety of the traction battery.

In addition to the stabilization of this nickel-rich cathode material, the rapid charging and discharging capability of the energy storage device is improved by the use of lasers to introduce structures into the surface of the electrode strips. Due to improved transport kinetics, this not only improves the electrochemical properties in the high-current range, but also homogenizes and accelerates the electrolyte filling during production as a side effect. This is particularly advantageous in thick electrode layers for high energy densities. The selection of the optimal structure design is based on simulation. The electrochemical processes in the Li-ion battery are mapped in a new, innovative electrochemical model, which can also be used after the project for the evaluation of new systems.

Through this holistic approach, RealLi! provides functional demonstration of an optimized Li-Ion battery which is characterized by increased safety, cycle stability, and high current capability compared to conventional systems manufactured with untreated electrodes (NMC811 and graphite). With the help of life cycle assessments, the entire life cycle of the new Li-ion battery (LIB) is evaluated and the recycling concepts, which are currently quite scarce for LIB, verified and their environmental effects evaluated.