リチウム金属負極の性能向上ために織物テンプレート法で特異構造な銅集電体の開発

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The use of collectors with a hierarchically porous structure can optimize the deposition behavior of lithium (Li) metal to some extent. However, in practical studies, Li metal was found to be difficult to be deposited into the upright channel as expected, in its place, the Li metal exhibits a different deposition behavior than we expected. When the channel's diameter is large (greater than 20 μm), lithium metal typically accumulates near the tube wall opening. Conversely, when the diameter is small (less than 5 μm), lithium metal deposits solely on the current collector's upper surface. Even after incorporating materials that promote underpotential deposition (UPD) or irregular nucleation of lithium metal (such as silver) into the metal framework, lithium metal will amass near the channel entrance, creating an unsupported lithium layer. This occurs because the initially deposited lithium metal on the upper surface acts as a "nucleus," encouraging subsequent deposition primarily on the electrode surface. The resulting lithium metal plating obstructs ion transport into the channel, causing deposition to predominantly occur in the 3D structure's shallow region. Moreover, we find that the use of such materials can improve the performance of the sulfur cathode in lithium-sulfur batteries very well. The porous metal possesses an exceptional capacity to catalyze the cathodic reactions, while its multi-level porous architecture effectively enhances the discharge performance of high-capacity lithium-sulfur batteries.