Aqueous Zn‐MnO2 batteries using mild electrolyte show great potential in large‐scale energy storage (LSES) application, due to high safety and low cost. However, structure collapse of manganese oxides upon cycling caused by the conversion mechanism (e.g., from tunnel to layer structures for α‐, β‐, and γ‐phases) is one of the most urgent issues plaguing its practical applications. Herein, to avoid the phase conversion issue and enhance battery performance, a structurally robust novel phase of manganese oxide MnO2H0.16(H2O)0.27 (MON) nanosheet with thickness of ≈2.5 nm is designed and synthesized as a promising cathode material, in which a nanosheet structure combined with a novel H+/Zn2+ synergistic intercalation mechanism is demonstrated and evidenced. Accordingly, a high‐performance Zn/MON cell is achieved, showing a high energy density of ≈228.5 Wh kg−1, impressive cyclability with capacity retention of 96% at 0.5 C after 300 cycles, as well as exhibiting rate performance of 115.1 mAh g−1 at current rate of 10 C. To the best current knowledge, this H+/Zn2+ synergistic intercalation mechanism is first reported in an aqueous battery system, which opens a new opportunity for development of high‐performance aqueous Zn ion batteries for LSES.

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Owing to the merits of low cost, high safety and environmental benignity, rechargeable aqueous Zn-based batteries (ZBs) have gained tremendous attention in recent years. Nevertheless, the poor reversibility of Zn anodes that originates from dendrite growth, surface passivation and corrosion, severely hinders the further development of ZBs. To tackle these issues, here we report a Janus separator based on a Zn-ion conductive metal–organic framework (MOF) and reduced graphene oxide (rGO), which is able to regulate uniform Zn2+ flux and electron conduction simultaneously during battery operation. Facilitated by the MOF/rGO bifunctional interlayers, the Zn anodes demonstrate stable plating/stripping behavior (over 500 h at 1 mA cm−2), high Coulombic efficiency (99.2% at 2 mA cm−2 after 100 cycles) and reduced redox barrier. Moreover, it is also found that the Zn corrosion can be effectively retarded through diminishing the potential discrepancy on Zn surface. Such a separator engineering also saliently promotes the overall performance of Zn|MnO2 full cells, which deliver nearly 100% capacity retention after 2000 cycles at 4 A g−1 and high power density over 10 kW kg−1. This work provides a feasible route to the high-performance Zn anodes for ZBs.

Lithium–sulfur (Li–S) batteries have been regarded as a promising energy‐storage system owing to their high theoretical energy density of 2600 Wh kg−1 and low cost of raw materials. However, the dendrite issue of Li metal anodes and the shuttle effect of polysulfides severely plague the safety and cycling stability of Li–S batteries. To address these problems, a novel nanoporous battery separator (MMMS) is designed based on an anionic metal–organic framework (MOF) UiO‐66‐SO3Li and poly(vinylidene fluoride) (PVDF) following a mixed‐matrix membrane approach. Benefitting from the well‐defined anionic Li+ transport tunnels across the MMMS, a homogeneous Li deposition is achieved to stabilize the plating/stripping cycling over 1000 h at a high current density of 5 mA cm−2. Moreover, these tunnels featuring anionic electrostatic repulsion and a proper aperture size also demonstrate strong suppression to polysulfide shuttle and promote the redox activity and utilization of sulfur cathode material. With the MMMS to simultaneously promote the performance of Li metal anode and sulfur cathode, the Li–S battery delivers an elevated charge/discharge rate up to 5 C (552 mAh g−1) as well as a low capacity fading (0.056% per cycle at its steady stage) over 500 cycles at 0.5 C.

During nervous system development, the extracellular matrix (ECM) plays a pivotal role through surface topography and microenvironment signals in neurons and neurites maturation. Topography and microenvironment signals act as physical...

The relatively low capacity and capacity fade of spinel LiMn2O4 (LMO) limit its application as a cathode material for lithium‐ion batteries. Extending the potential window of LMO below 3 V to access double capacity would be fantastic but hard to be realized, as it will lead to fast capacity loss due to the serious Jahn–Teller distortion. Here using experiments combined with extensive ab initio calculations, it is proved that there is a cooperative effect among individual Jahn–Teller distortions of Mn3+O6 octahedrons in LMO, named as cooperative Jahn–Teller distortion (CJTD) in the text, which is the difficulty to access the capacity beyond one lithium intercalation. It is further proposed that the cationic disordering (excess Li at Mn sites and Li/Mn exchange) can intrinsically suppress the CJTD of Mn3+O6 octahedrons. The cationic disordering can break the symmetry of Mn3+ arrangements to disrupt the correlation of distortions arising from individual JT centers and prevent the Mn3+O bonds distorting along one direction. Interestingly, with the suppressed CJTD, the original octahedral vacancies in spinel LMO are activated and can serve as extra Li‐ion storage sites to access the double capacity with good reversible cycling stability in microsized LMO.

Poly(ethylene oxide) (PEO) is a promising solid electrolyte material for solidstate lithium-sulfur (Li-S) batteries, but low intrinsic ionic conductivity, poor mechanical properties, and failure to hinder the polysulfide shuttle effect limits its application. Herein, a polymer of intrinsic microporosity (PIM) is synthesized and applied as an organic framework to comprehensively enhance the performance of PEO by forming a composite electrolyte (PEO-PIM). The unique structure of PIM-1 not only enhances the mechanical strength and hardness over the PEO electrolyte by an order of magnitude, increasing stability toward the metallic lithium anode but also increases its ionic conductivity by lowering the degree of crystallinity. Furthermore, the PIM-1 is shown to effectively trap lithium polysulfide species to mitigate against the detrimental polysulfide shuttle effect, as electrophilic 1,4-dicyanooxanthrene functional groups possess higher binding energy to polysulfides. Benefiting from these properties, the use of PEO-PIM composite electrolyte has achieved greatly improved rate performance, long-cycling stability, and excellent safety features for solid-state Li-S batteries. This methodology offers a new direction for the optimization of solid polymer electrolytes.