The urgent desire for high-energy lithium-ion batteries (LIBs) has motivated scientists to develop large-capacity electrode materials with innovative compositions and/or architectures. Herein, we report a three-dimensional (3D) hierarchical MoO2/MoS2/C heterostructure...

Lithium‐ion batteries using inorganic electrode materials have been long demonstrated as the most promising power supplies for portable electronics, electric vehicles, and smart grids. However, the increasing cost and descending availability of lithium resources in combination with the limited electrochemical performance and eco‐sustainability have created serious concerns with the competitiveness of lithium‐ion batteries. There is a pressing need for the discovery of new redox chemistries between the alternative host materials and charge carriers. Organic nonlithium batteries using organic electrodes have recently attracted considerable interests as the future substitutes for energy storage systems, because of their combined merits (e.g., natural abundance, rich chemistry of organics, rapid kinetics, and multielectron redox) of Li‐free batteries and organic electrodes. Herein, an overview on the state‐of‐the‐art developments of emerging carbonyl polymers for nonlithium metal‐ion batteries is comprehensively presented with a primary focus on polyquinones and polyimides from the perspective of chain engineering. Six distinct categories, including monovalent (Na+, K+) and multivalent (Mg2+, Zn2+, Ca2+, Al3+) metal‐ions batteries are individually outlined. Advantages of polymer electrode materials and characteristics of charge storage mechanisms are highlighted. Some key performance parameters such as specific capacity, rate capability, and cycle stability are carefully discussed. Moreover, aqueous nonlithium batteries based on carbonyl polymers are specially scrutinized due to the less reactivity of Li‐free metals when exposed in aqueous electrolytes and ambient atmosphere. Current challenges and future prospects of developing polymer‐based batteries are proposed finally. This review provides a fundamental guidance for the future advancement of next‐generation sustainable batteries beyond lithium‐ion batteries.

The sustainable development of lithium-ion batteries (LIBs) urges electrode materials being low-cost, richly sourced, environmentally benign, and with recycling capability. Polyimides (PIs) as a promising alternative to transition-metal-based cathodes for...

In-situ uniform confinement of ultrasmall Mo2C nanocrystals into micropore-enriched N-doped carbons was achieved by carbonizing phosphomolybdic acid/polyimide precursors to craft a surface-dominated capacitive battery-type anode. Upon coupling with a capacitor-type...

Rational engineering of electrode materials and device configurations are significantly pivotal to develop high-energy supercapacitors without sacrificing strong power capability and long lifespan. Herein, a Schiff-base condensation between phthalaldehydes and anthraquinones was readily performed to yield chain-engineered polyquinones (PQs) with tailored redox-active multi-hydroxyl groups. Further in situ incorporation of conductive graphene into PQs produced the composites. The symmetric supercapacitor (SSC) based on two identical composite electrodes delivers an energy density of 9.3 W h kg–1 at a power density of 99.9 W kg–1 and 6.2 W h kg–1 at 4000.0 W kg–1, respectively, outperforming the pure PQ-based SSC (9.2 W h kg–1 at 150.2 W kg–1 and 3.2 W h kg–1 at 1515.8 W kg–1). Furthermore, the graphene/PQ composite coupled with a counter electrode of activated carbon (AC) was actualized to assemble an asymmetric supercapacitor (ASSC), which enables higher power and energy outputs (20.3 W h kg–1 at 350.2 W kg–1 and 10.3 W h kg–1 at 6980.2 W kg–1) compared to the SSC device. Finally, a lithium-ion capacitor (LIC) was constructed using a composite anode and an AC cathode. Remarkably, such a full-cell delivers an energy density up to 113.8 W h kg–1 at 180.8 W kg–1 and retains 59.2 W h kg–1 at 9063.4 W kg–1, much higher than its counterparts of ASSC, SSC, and many supercapacitors reported previously. This LIC also exhibits a nearly 80% of initial capacitance after running at 5 A g–1 over 2000 cycles, showcasing an excellent energy–power–lifespan combination.