Asymmetric Structure Design of Electrolytes with Flexibility and Lithium Dendrite-Suppression Ability for Solid-State Lithium Batteries

Co-Regulating Solvation Structure and Hydrogen Bond Network via Bio-Inspired Additive for Highly Reversible Zinc Anode

The feasibility of aqueous zinc-ion batteries for large-scale energy storage is hindered by the inherent challenges of Zn anode. Drawing inspiration from cellular mechanisms governing metal ion and nutrient transport, erythritol is introduced, a zincophilic additive, into the ZnSO4 electrolyte. This innovation stabilizes the Zn anode via chelation interactions between polysaccharides and Zn2+. Experimental tests in conjunction with theoretical calculation results verified that the erythritol additive can simultaneously regulate the solvation structure of hydrated Zn2+ and reconstruct the hydrogen bond network within the solution environment. Additionally, erythritol molecules preferentially adsorb onto the Zn anode, forming a dynamic protective layer. These modifications significantly mitigate undesirable side reactions, thus enhancing the Zn2+ transport and deposition behavior. Consequently, there is a notable increase in cumulative capacity, reaching 6000 mA h cm⁻2 at a current density of 5 mA cm-2. Specifically, a high average coulombic efficiency of 99.72% and long cycling stability of >500 cycles are obtained at 2 mA cm-2 and 1 mA h cm-2. Furthermore, full batteries comprised of MnO2 cathode and Zn anode in an erythritol-containing electrolyte deliver superior capacity retention. This work provides a strategy to promote the performance of Zn anodes toward practical applications.

Cu(N2)-Li Battery for Ammonia Synthesis

The cathodic mechanism of Li-N2 batteries is similar to Li-mediated N2 reduction (LiNR). Herein, the Li-N2, LiNR, and Cu-Li battery were amalgamated to a milliliter-scale Cu(N2)-Li system. The utilization of a lithium anode with lithium oxidation reaction (LiOR), ensures an uninterrupted supply of lithium ions to active N2. LiOR not only enhances electrolyte stability but also reduces voltage by stripping Li ions, in contrast to the inert platinum anode, commonly employed in LiNR. Notably, an unusual observation of ammonia accumulation within the anode chamber elucidates the presence and role of reaction intermediates. The charging process aimed at lithium regeneration faces high polarization, and a cycling procedure involving low-current charging was proposed to improve cycling. This study integrates insights from three distinct research directions to leverage their respective advantages and scientific insights. The Li-N2 battery emerges as a highly advantageous strategy for ammonia synthesis due to the progressiveness of lithium anode.

Design Strategies toward High-Performance Zn Metal Anode

Rechargeable aqueous Zn-ion batteries (AZIBs) are one of the most promising alternatives for traditional energy-storage devices because of their low cost, abundant resources, environmental friendliness, and inherent safety. However, several detrimental issues with Zn metal anodes including Zn dendrite formation, hydrogen evolution, corrosion and passivation, should be considered when designing advanced AZIBs. Moreover, these thorny issues are not independent but mutually reinforcing, covering many technical and processing parameters. Therefore, it is necessary to comprehensively summarize the issues facing Zn anodes and the corresponding strategies to develop roadmaps for the development of high-performance Zn anodes. Herein, the failure mechanisms of Zn anodes and their corresponding impacts are outlined. Recent progress on improving the stability of Zn anode is summarized, including structurally designed Zn anodes, Zn alloy anodes, surface modification, electrolyte optimization, and separator design. Finally, this review provides brilliant and insightful perspectives for stable Zn metal anodes and promotes the large-scale application of AZIBs in power grid systems.

Progress of Polymer Electrolytes Worked in Solid-State Lithium Batteries for Wide-Temperature Application

Solid-state Li-ion batteries have emerged as the most promising next-generation energy storage systems, offering theoretical advantages such as superior safety and higher energy density. However, polymer-based solid-state Li-ion batteries face challenges across wide temperature ranges. The primary issue lies in the fact that most polymer electrolytes exhibit relatively low ionic conductivity at or below room temperature. This sensitivity to temperature variations poses challenges in operating solid-state lithium batteries at sub-zero temperatures. Moreover, elevated working temperatures lead to polymer shrinkage and deformation, ultimately resulting in battery failure. To address this challenge of polymer-based solid-state batteries, this review presents an overview of various promising polymer electrolyte systems. The review provides insights into the temperature-dependent physical and electrochemical properties of polymers, aiming to expand the temperature range of operation. The review also further summarizes modification strategies for polymer electrolytes suited to diverse temperatures. The final section summarizes the performance of various polymer-based solid-state batteries at different temperatures. Valuable insights and potential future research directions for designing wide-temperature polymer electrolytes are presented based on the differences in battery performance. This information is intended to inspire practical applications of wide-temperature polymer-based solid-state batteries.

Self-shutdown function induced by sandwich-like gel polymer electrolytes for high safety lithium metal batteries

Lithium-ion batteries using either liquid electrolytes or solid electrolytes have been extensively studied in recent years, but both of these encounter safety risks such as flammability of liquid electrolytes and uncontrolled dendrite growth. In this study, a sandwich gel polymer electrolyte (SGPE) with a thermal shutdown function was developed to resolve the safety issues. By adjustment of surface pore size of the SGPE, lithium dendrite growth is suppressed. Due to the sandwich structure design, the SGPE can effectively respond to an overheating environment, regulate lithium ion transport and inhibit the penetration of lithium dendrite, demonstrating a remarkably high safety of the batteries, especially at high temperature or under thermal runaway circumstances. In addition, the LiFePO4/SGPE/Li battery exhibits a high reversible capacity of 135 mA h g-1 at 1C and maintains high capacity retention (>95%) after 200 charge-discharge cycles. This study shows a great advantage to handle thermal abuse and a stable lithium anode, suggesting a promising approach to the high safety lithium metal batteries.

Dense PVDF-type polymer-in-ceramic electrolytes for solid state lithium batteries

Li₇La₃Zr_1.4Ta_0.6O₁₂ (LLZTO) and polyvinylidene fluoride (PVDF) composite electrolytes (LPCEs) with a high ceramic content up to 80 wt% have been developed. Hot pressing can significantly reduce the porosity of LPCEs and increase the conductivity to 1.08 × 10⁻⁴ S cm⁻¹ at 60 °C, then the LPCEs can sustain Li plating/stripping cycling for over 1500 h, and make LiFePO₄/LPCE/Li cell display a capacity retention of 86% in 200 cycles.

Li₇La₃Zr_1.4Ta_0.6O₁₂ (LLZTO) and polyvinylidene fluoride (PVDF) composite electrolytes (LPCEs) with a high ceramic content up to 80 wt% have been developed.