Single-atom catalysts have been paid more attention to improving sluggish reaction kinetics and anchoring polysulfide for lithium−sulfur (Li−S) batteries. It has been demonstrated that d-block single-atom elements in the fourth period can chemically interact with the local environment, leading to effective adsorption and catalytic activity toward lithium polysulfides. Enlightened by theoretical screening, for the first time, we design novel single-atom Nb catalysts toward improved sulfur immobilization and catalyzation. Calculations reveal that Nb−N 4 active moiety possesses abundant unfilled antibonding orbitals, which promotes d-p hybridization and enhances anchoring capability toward lithium polysulfides via a "trapping−coupling−conversion" mechanism. The Nb−SAs@NC cell exhibits a high capacity retention of over 85% after 1000 cycles, a superior rate performance of 740 mA h g −1 at 7 C, and a competitive areal capacity of 5.2 mAh cm −2 (5.6 mg cm −2 ). Our work provides a new perspective to extend cathodes enabling high-energy-density Li−S batteries.

Developing "ideal" binders to achieve ultrahigh area-capacity stable silicon (Si) anodes remains a significant challenge. Herein, a self-healing binder with a multilevel buffered structure is designed to alleviate the structural damage and performance degradation caused by extreme volume deformation of Si. In this multilevel configuration, employing the coexistence strategy of dynamic supramolecular interactions and rigid covalent bonds, the dopamine-grafted poly(acrylic acid) (PAA-DA) possesses abundant hydrogen bonds and strong viscoelasticity, which facilitates the dynamic reconstruction of the entire network. Moreover, the hydroxyl groups on the polyethylene glycol (PVA) form a strong covalent bond network with the carboxyl groups in PAA-DA under thermal polymerization conditions to ensure the integrity of the electrode structure. At 4 A g −1 , the resulting Si electrode retains 1974.1 mAh g −1 after 500 cycles. This binder design strategy with dynamic repair and stable network structure gives specific inspiration for developing high-energy-density batteries.

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With the development of flexible devices, it is necessary to design high-performance power supplies with superior flexibility, durability, safety, etc., to ensure that they can be deformed with the device while retaining their electrochemical functions. Herein, we have designed a flexible lithium-ion battery inspired by the DNA helix structure. The battery structure is mainly composed of multiple thick energy stacks for energy storage and some grooves for stress buffers, which realized the spiral deformation of batteries. According to the results, the batteries exhibit less than 3% capacity degradation even after more than 31000 times of in situ dynamic mechanical loadings. Moreover, the mechanism of the battery with spiral deformability is further revealed. It is anticipated that this bioinspired design strategy could create unique opportunities for the commercialization of flexible batteries and fill the current gap in realizing battery-specific deformations to meet various requirements for future complex device designs.

Mitigating the mechanical degradation and enhancing the ionic/electronic conductivity are critical but challengeable issues toward improving electrochemical performance of conversion‐type anodes in rechargeable batteries. Herein, these challenges are addressed by constructing interconnected 3D hierarchically porous structure synergistic with Nb single atom modulation within a Co3O4 nanocage (3DH‐Co3O4@Nb). Such a hierarchical‐structure nanocage affords several fantastic merits such as rapid ion migration and enough inner space for alleviating volume variation induced by intragrain stress and optimized stability of the solid‐electrolyte interface. Particularly, experimental studies in combination with theoretical analysis verify that the introduction of Nb into the Co3O4 lattice not only improves the electron conductivity, but also accelerates the surface/near‐surface reactions defined as pesudocapacitance behavior. Dynamic behavior reveals that the ensemble design shows huge potential for fast and large lithium storage. These features endow 3DH‐Co3O4@Nb with remarkable battery performance, delivering ≈740 mA h g−1 after ultra‐long cycling of 1000 times under a high current density of 5 A g−1. Importantly, the assembled 3DH‐Co3O4@Nb//LiCoO2 pouch cell also presents a long‐lived cycle performance with only ≈0.059% capacity decay per cycle, inspiring the design of electrode materials from both the nanostructure and atomic level toward practical applications.