Lithophilic conductive oxide-introduced dual-substrate deposition for high current density lithium metal batteries

Abstract

Lithium (Li) metal anodes hold tremendous potential for high-energy storage applications, yet their practical implementation is severely hindered by the formation of Li dendrites, which compromise both battery lifespan and safety. In this study, yttrium-barium-copper-oxide (YBa2Cu3O7, YBCO) is introduced as a separator modifier due to its outstanding conductivity and strong Li⁺ adsorption affinity, thus YBCO effectively reduces local current density on Li anode and promotes uniform Li deposition through a two-dimensional growth pattern on YBCO. Consequently, compared to the cells with a pristine PP separator, those incorporating modified separators lead to an extended lifespan in both Li/Li symmetric cells (2800 h) and Li/Cu half-cells (400 h). Moreover, the cycling stability of Li metal batteries is greatly improved, with LiFePO₄/Li full cells retaining 82% of highest capacity even after 600 cycles at 5 C. This study presents a practical and efficient approach to separator modification, paving the way for a highly desired dendrite-free Li anode and the development of long-lasting Li metal batteries, especially under a high current density.