Delocalized Solvation Structures Design Enables 600 Wh kg-1 Lithium Metal Pouch Cells

Developing high-energy lithium metal batteries (LMBs) is essential for advancing next-generation energy storage and electric vehicle technologies. Nevertheless, the practical application remains constrained by current electrolyte designs with inherent reliance on dominant solvation structures, constraining transformative progress in performance optimization. Herein, we address this limitation through a delocalized electrolyte design paradigm that fosters a more disordered solvation microenvironment, thereby mitigating dynamic barriers and stabilizing interphases. The resulting delocalized electrolyte delivers notable energy densities of 604.2 Wh kg-1 in a 5.5 Ah LiNi0.9Co0.05Mn0.05O2 (Ni90)||Li pouch cell with a lean electrolyte design (1 g Ah−1) and 618.2 Wh kg-1 in a 5.2 Ah Ni90||Li pouch cell with an ultra-lean electrolyte design (0.9 g Ah⁻¹), maintaining significant cycle stability over 100 and 90 cycles, respectively. Additionally, the first reported 70-104 V NCM811||Li battery pack (3904 Wh) exhibits a high energy density of 480.9 Wh kg-1 and stable cycling over 25 cycles. This work underscores the imperative to circumvent the inherent reliance on dominant solvation structures in electrolyte design, thereby facilitating the milestone performance of high-energy “Battery600” and scalable “Pack480”.