Lithium Powder Synthesis and Preparation of Powder-Based Composite Electrodes for Application in Lithium Metal Batteries

The electrochemical performance of lithium metal batteries is affected by many factors, among which the negative electrode is crucial. Although much of the research is focused on lithium metal electrodes from metallic foils, lithium metal powder can also provide several advantages. Herein, the synthesis of lithium metal powder (Li-p) using a droplet emulsion technique is described in detail and the scientific background of the method is provided. Furthermore, the electrochemical performance of the composite Li-p-based electrodes prepared with conductive carbon additive (Super C65) via the electrode paste-casting method is reported. The results indicate that under the same material loading, the composite Li-p-based electrodes can provide at least twice the practical electrode capacity of pure Li-p electrodes and with lower overpotentials, as shown in symmetric Li||Li cells. Full cells assembled with an NMC622 cathode and a composite Li-p-based electrode are cycled at least for 100 cycles and show improved cycling performance as compared with the full cells assembled with pure Li-p electrodes. In addition, the results also conclude that there are four different types of charge storage mechanisms in these composite Li-p-based electrodes. These occurring mechanisms should be considered when engineering lithium metal electrodes with various designs.