Silicon (Si) is one of the most promising anode candidates to further push the energy density of lithium ion batteries. However, its practical usage is still hindered by parasitic side reactions including electrolyte decomposition and continuous breakage and (re‐)formation of the solid electrolyte interphase (SEI), leading to consumption of active lithium. Pre‐lithiation is considered a highly appealing technique to compensate for active lithium losses. A critical parameter for a successful pre‐lithiation strategy by means of Li metal is to achieve lithiation of the active material/composite anode at the most uniform lateral and in‐depth distribution possible. Despite extensive exploration of various pre‐lithiation techniques, controlling the lithium amount precisely while keeping a homogeneous lithium distribution remains challenging. Here, the thermal evaporation of Li metal as a novel pre‐lithiation technique for pure Si anodes that allows both, that is, precise control of the degree of pre‐lithiation and a homogeneous Li deposition at the surface is reported. Li nucleation, mechanical cracking, and the ongoing phase changes are thoroughly evaluated. The terms dry‐state and wet‐state pre‐lithiation (without/with electrolyte) are revisited. Finally, a series of electrochemical methods are performed to allow a direct correlation of pre‐SEI formation with the electrochemical performance of pre‐lithiated Si.

Aqueous processing of positive electrode active materials (AMs) could enable a more economical and environmentally friendly production of lithium‐ion batteries. Intrinsically, aqueous processing of positive AMs is hampered by lithium‐proton exchange in the AM surface, leading to a poor electrochemical performance and a resulting strong increase in the pH value in the electrode paste, thereby corroding the aluminum current collector. Herein, the influence of different lithium salts as processing additive to tailor the pH value of the electrode paste, the manganese dissolution during processing, and the electrochemical performance is described for aqueous processing of LiNi0.5Mn1.5O4‐based positive electrodes. Positive electrodes, based on an aqueous LiNi0.5Mn1.5O4‐based electrode paste which is mixed with LiN(SO2CF3)2 (LiTFSI), achieve a comparable electrochemical performance to state‐of‐the‐art nonaqueous‐processed electrodes. Manganese dissolution into the electrode paste is examined by inductively coupled plasma‐mass spectrometry (ICP‐MS), showing that the addition of lithium salts to the electrode paste substantially decreases manganese leaching during processing. Furthermore, postmortem analysis shows that the addition of LiTFSI to the electrode paste has a positive effect not only during processing but also on charge/discharge cycling performance.

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