Innovative Formation Process for Lithium Ion Batteries Reduces Energy and Time Consumption

Increased Efficiency and Sustainability in Battery Production

Formation is essential in the production of lithium ion batteries, but requires a substantial investment of time and energy. During these first charging and discharging cycles, the protective layer between the electrodes and the electrolyte is formed. A team from the MEET Battery Research Center at the University of Münster has now developed an innovative formation process that reduces time and energy consumption while preserving the performance and lifetime of the batteries.

Combination of Low Voltage and Defined Charge Currents

The scientists investigated how different voltage windows and charge currents affect the formation process. They identified a low cut-off voltage of 3.6 Volt in combination with charging rates of 0.5 C (charge or discharge current in relation to capacity) and 0.2 C as the optimum parameters for the formation process. “This way, the time required can be reduced by up to 85 percent and energy consumption by more than 80 percent,” explains MEET researcher Christian Clephas. At the same time, the performance and lifetime of the batteries remain unchanged. After cyclic aging, the scientists even observed a moderate increase in capacity retention.

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In addition, the research team analyzed the dQ/dV vs. capacity curve, which provides precise insights into battery behaviour at certain state of charges  in the charging and discharging cycles. They observed the electrolyte decomposition peaks to gain an even better understanding of the mechanisms during formation and thus be able to optimize the charging rates. “Our results are an important step towards increasing efficiency and sustainability in battery production,” concludes Clephas.

Detailed Results Online Available

The entire study has been published by the authors Christian Clephas, Dr Bastian Heidrich and Dr Philip Niehoff, MEET Battery Research Center, as well as Prof. Dr Martin Winter, MEET Battery Research Center and Helmholtz Institute Münster of Forschungszentrum Jülich, in the “Journal of The Electrochemical Society”.