Rechargeable aluminum-ion batteries (AIBs) possess significant advantages of high energy density, safety performance, and abundant natural resources, making them one of the desirable next-generation substitutes for lithium battery systems. However, the poor reversibility, short lifespan, and low capacity of positive materials have limited its practical applications. In comparison with semiconductors, the metallic nickel telluride (NiTe) alloy with enhanced electrical conductivity and fast electron transmission is a more favorable electrode material that could significantly decrease the kinetic barrier during battery operation for energy storage. In this paper, the NiTe nanorods prepared through a simple hydrothermal routine enable an initial reversible capacity of approximately 570 mA h g −1 (under the current density of 200 mA g −1 ) to be delivered on the basis of the ionic liquid electrolyte, along with the average voltage platform of about 1.30 V. Moreover, the cycling performance could be easily enhanced using a modified separator to prevent the diffusion of soluble intermediate species to the negative electrode side. At a high rate of 500 mA g −1 , the NiTe nanorods could retain a specific capacity of about 307 mA h g −1 at the 100th cycle. The results have important implications for the research of transition metal tellurides as positive electrode materials for AIBs.

As one of the emerging safe energy‐storage devices with high energy‐to‐cost ratio, nonaqueous aluminum batteries with enhanced energy density are intensively pursued by researchers. Although significant progress has been made on positive electrode materials, the effective energy density of aluminum batteries is still limited by the presence of high‐density refractory metal current collectors, which are known to be electrochemically inert in highly acidic ionic‐liquid electrolytes. To address such critical issues, here, a novel low‐density (<2 g cm−3) nonmetal current collector is presented, which uses poly(ethylene terephthalate) (PET) substrates coated with indium tin oxide (ITO), with the purpose of significantly reducing the ratio of nonactive components in the electrodes. In addition to the excellent chemical and electrochemical stability (with voltage as high as ≈2.75 V vs Al3+/Al), this nonmetal current collector, also encompassing a carboxymethyl cellulose (CMC) binder, allows as‐assembled pouch cells to deliver a reversible specific capacity of ≈120 mAh g−1 at a current density of 50 mA g−1. In comparison with the high‐density refractory metal Mo or Ta current collectors, these nonmetal current collectors offer a novel strategy for constructing high‐energy‐density aluminum batteries by substituting the key components, with the aim of boosting the energy density of nonaqueous aluminum batteries.

Because of the unprecedented development and popularization of portable electronics, electric vehicles, and smart grid, rechargeable batteries have become one of the hottest topics within worldwide research for the past decade. Among all of the proposed nonlithium-based battery systems, rechargeable aluminum-ion batteries (RAIBs) are considered as a promising candidate due to aluminum's abundance and safety. Naturally, exploring compatible and high-performance cathode materials for RAIBs becomes a key issue for pushing RAIBs from lab-level to industrialization. In this work, we report a novel highperformance RAIB system using MOF-derived Co 3 O 4 @MWCNTs polyhedron composite as cathode. The well-defined morphology of MOF-derived Co 3 O 4 and enhancement brought by MWCNTs allow Co 3 O 4 @MWCNTs polyhedrons to deliver an initial discharge capacity of ca. 266.3 mAh g −1 , and the reversible specific capacity can reach 125 mAh g −1 at 100 mA g −1 over 150 cycles. The energy storage mechanism has been verified to be a reversible valence-change reaction between Co 3 O 4 and Co. These findings can enlighten future research regrading MOF derivatives as advanced cathode materials for RAIBs.

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Recently, aluminum-ion batteries have been receiving growing attention based on their low cost, good safety, and excellent capacity. In this work, the coral-like TeO 2 microwires synthesized by two-step thermal treatment can be revealed as excellent aluminum-ion battery cathodes. It delivers a capacity of 214.2 mAh g −1 and a relatively high-voltage plateau of ∼1.3 V at 200 mA g −1 and remains at 88.5 mAh g −1 over 100 cycles. Moreover, the reaction mechanism of TeO 2 is verified as the insertion of Al 3+ ions during discharging. More importantly, based on the design of acetylene black-modified separator, the higher reversible capacity of 152.0 mAh g −1 can be achieved over 150 cycles at 200 mA g −1 with a high Coulombic efficiency of 98.4%. At a higher current density of 500 mA g −1 , the battery can reach a stable capacity of 91.1 mAh g −1 over 700 cycles, displaying the superior long-term cycling stability, high capacity, and good rate capability. The results indicate that the coral-like TeO 2 microwires and acetylene black-modified separator can open up a new opportunity and be of great significance for further development of highcapacity and high-stability aluminum-ion batteries.