The traditional working principle within lithium-ion batteries relies on Li⁺ shuttling between the cathode and anode, namely the rocking-chair mechanism. A single working ion constrains the possibilities for battery design and the selection of electrode materials, while realizing multiple working ions offers the potential to break through the fundamental principles of traditional battery construction. Accordingly, it is necessary to develop dual-ion conductors to enable the migration of multiple working ions. This focus article starts by introducing traditional dual-ion batteries based on liquid electrolytes and their pros and cons. Then, solidifying liquid dual-ion conductors is expected to overcome these drawbacks, so the development of solid dual-ion conductors is discussed in detail. Specifically, basic design principles of solid dual-ion conductors are briefly proposed, including constructing continuous ion transport channels and choosing appropriately sized ion carriers. The potential applications of solid dual-ion conductors are also summarized, such as stabilizing the electrode/electrolyte interface and activating additional redox couples. The goal of this article is to inspire researchers in the development of dual-ion conductors and to contribute to the advancement of all-solid-state batteries.

中文翻译：

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双离子导体：从液体到固体

锂离子电池的传统工作原理依赖于Li ⁺在阴极和阳极之间穿梭，即摇椅机制。单一工作离子限制了电池设计和电极材料选择的可能性，而实现多个工作离子则有可能突破传统电池构造的基本原理。因此，有必要开发双离子导体以实现多个工作离子的迁移。本篇焦点文章首先介绍基于液体电解质的传统双离子电池及其优缺点。那么，固化液体双离子导体有望克服这些缺点，因此详细讨论了固体双离子导体的发展。具体来说，简要提出了固体双离子导体的基本设计原理，包括构建连续的离子传输通道和选择适当尺寸的离子载体。还总结了固体双离子导体的潜在应用，例如稳定电极/电解质界面和激活额外的氧化还原对。本文的目的是激励研究人员开发双离子导体，并为全固态电池的进步做出贡献。