Organic electrode materials are promising alternatives to transition-metal based intercalation compounds for the next generation of high-performance and sustainable batteries. Herein, a novel quinone-based organic, lithium salt of poly(2,5-dihydroxy-p-benzoquinonyl sulfide) (Li₂PDHBQS), was successfully synthesized through a simple one-step polycondensation reaction, and applied as a cathode for Li–organic batteries. As an oligomeric lithium salt with average polymerization degree of 7, Li₂PDHBQS combines the advantages of the O⋯Li⋯O coordination bond and increased molecular weight, thus solves absolutely the dissolution problem of active material in non-aqueous electrolytes, which has seriously hindered development of organic electrode materials. Benefiting from the high theoretical capacity, intrinsic insolubility, fast reaction kinetics of the quinone group, accelerated Li-ion transport and uniform blending with conductive carbon, as well as the stable amorphous structure, Li₂PDHBQS shows superior comprehensive electrochemical performance including high reversible capacity (268 mA h g⁻¹), high cycling stability (1500 cycles, 90%), high rate capability (5000 mA g⁻¹, 83%) and high Coulombic efficiency (99.9–100.1%). Investigation of the structure–property relationship of Li₂PDHBQS and its analogues also gives new insights into developing novel quinone-based organic electrode materials, for building better Li–organic or Na–organic batteries beyond traditional Li-ion batteries.

The practical applications of Li‐ion batteries (LIBs) are challenged by their safety concerns when using liquid electrolytes (LEs). Solid‐state gel polymer electrolytes (GPEs) can address this challenge and have drawn increased attention recently. Normally, GPEs are prepared separately and then assembled into cells, which undoubtedly result in dissatisfactory solid/solid interfacial compatibility and low ionic conductivity. Fortunately, in situ GPEs are proposed to address the above challenges and simplify the preparation process. Typically, LE precursor is injected into the cells and gradually transformed into a quasi‐solid gel state under the conditions of thermal or chemical initiators. Consequently, the obtained in situ GPEs could fully infiltrate the electrode and better interface contact of gel electrolyte/electrode is thus inherited. In this review, the authors focus on the in situ GPEs used in lithium batteries (LBs), and summarize recent progress of the design, synthesis, and applications of in situ GPEs. Based on the different ways of triggering polymerization, there are mainly three methods: thermochemical gelation, polymerization by additional chemical initiators, and cross‐linking initiated by LiO bond. Composite GPEs based on in situ solidification method are introduced as a promising strategy to improve the electrochemical performances. Finally, up‐to‐date research progresses are discussed, and perspectives are provided on the development and challenges of in situ GPEs to meet the requirements for their practical applications in LBs. image

Rechargeable metal-iodine batteries are an emerging attractive electrochemical energy storage technology that combines metallic anodes with halogen cathodes. Such batteries using aqueous electrolytes represent a viable solution for the safety and cost issues associated with organic electrolytes. A hybrid-electrolyte battery architecture has been adopted in a lithium-iodine battery using a solid ceramic membrane that protects the metallic anode from contacting the aqueous electrolyte. Here we demonstrate an eco-friendly, low-cost zinc-iodine battery with an aqueous electrolyte, wherein active I2 is confined in a nanoporous carbon cloth substrate. The electrochemical reaction is confined in the nanopores as a single conversion reaction, thus avoiding the production of I₃⁻ intermediates. The cathode architecture fully utilizes the active I₂, showing a capacity of 255 mAh·g⁻¹ and low capacity cycling fading. The battery provides an energy density of ∼ 151 Wh·kg⁻¹ and exhibits an ultrastable cycle life of more than 1,500 cycles.

We demonstrate that a Li–O₂/CO₂ battery cycles via formation of peroxodicarbonate (C₂O₆²⁻) but not Li₂CO₃, and operates with a low charge potential of 3.5 V.