Pre-Lithiation of Electrodes (PräLi)

In order to fulfill the growing demand for lithium ion batteries with even higher energy-densities than they are available today, silicon has been identified as promising high-capacity material for anodes. Since silicon has a significantly higher capacity than graphite, Asian cell suppliers already incorporate it in high energy battery cells. Nevertheless, it is also well known that silicon has inherent disadvantages challenging the lifetime of lithium ion batteries by large volume variations when charging and discharging. Also, an increased consumption of electrolyte together with according irreversible lithium-losses are a typical drawback of silicon-based anodes. The latter will be addressed by the project PräLi, which aims at developing innovative processes for adding lithium to the anode already before assembling the cell – pre-lithiation. This lithium reservoir adds to the readily available lithium supplied by the cathode, which renders the resulting lithium ion battery cells with silicon much more stable when charging and discharging. The project partners systematically investigate the impact of pre-lithiation on the charge-discharge performance as well as its impact on the electrode morphology and interphase behavior. Moreover, the technical feasibility as well as economic aspects of various pre-lithiation processes will be evaluated.