Mechanism of Fast Storage of Li/Na in Complex Sb‐Based Hybrid System

Abstract

Antimony（Sb） has high theoretical specific capacity and moderate reaction potential, but poor cycling stability and rate performance caused by large volume expansion and sluggish reaction kinetics limit its development in alkali‐ion batteries. The construction of carbon/Sb composites can solve this problem, but the traditional single carbon composite and poor Sb/carbon interface have limited promotion. Here, under the guidance of theoretical calculations, a strategy of hierarchical double carbon composite is proposed to enhance the performance of Sb anode, and systematically reveal the lithium/sodium ions (Li+/Na+) storage mechanism of Sb in complex composite system. Sb nanoparticles (Sb NPs) are encapsulated in carbon sphere matrix with strong interfacial chemical bond to form the first level composite material, and then the highly conductive and mechanically strong graphene is used as a three‐dimensional skeleton network to connect the first level composite to form the second level composite material. The hierarchical double carbon/Sb composite exhibits excellent rate (228 mAh g−1 @ 20 A g−1) and long cycling performance (373.7 mAh g−1 @ 2 A g−1 after 2200 cycles, capacity retention of 93.1%). This work may expand structural design and interface regulation of Sb/C composites and providing theoretical guidance for metal anodes development.

One-step Solid-State Synthesis of V1.13Se2/V2O3 Heterostructure as a High Pseudocapacitance Anode for Fast-Charging Sodium-Ion Batteries

“…The b value approaching 0.5 signifies a diffusion-controlled sodium storage process, while the b value near 1 indicates the dominance of surface pseudocapacitance. 43 As depicted in Figures 4d and S9b, the calculated results reveal that the b values of all peaks for V 1.13 Se 2 /V 2 O 3 and V 1.13 Se 2 are approximately 1, implying that their sodium storage process is predominantly governed by pseudocapacitance, known for their swift response capabilities. V 1.13 Se 2 /V 2 O 3 heterostructure exhibits the highest capacitance fraction with values of 90.8, 92.6, 94.2, 96.2, and 96.7% at scan rates of 0.1, 0.3, 0.5, 0.8, and 1.0 mV s −1 (Figure 4e,f), respectively.…”

“…The slope value of b can be obtained by fitting the log v and log­( i ) plots. The b value approaching 0.5 signifies a diffusion-controlled sodium storage process, while the b value near 1 indicates the dominance of surface pseudocapacitance . As depicted in Figures d and S9b, the calculated results reveal that the b values of all peaks for V 1.13 Se 2 /V 2 O 3 and V 1.13 Se 2 are approximately 1, implying that their sodium storage process is predominantly governed by pseudocapacitance, known for their swift response capabilities.…”

MOF-Derived Bimetallic Selenide CoNiSe2 Nanododecahedrons Encapsulated in Porous Carbon Matrix as Advanced Anodes for Lithium-Ion Batteries

“…The continuous advancement and development of energy storage devices have led to significant progress in mitigating environmental degradation and addressing energy depletion. Among these devices, lithium-ion batteries (LIBs) are widely used in electronic devices and new energy vehicles due to their remarkable energy density, extended cycle life, and cost effectiveness. − It is widely recognized that the anode materials play a critical role in improving their electrochemical performance. − However, current commercial graphite anodes have a low specific capacity of 372 mA h g –1 and a low Li potential of 0.01–0.2 V vs Li + /Li, which is close to the Li deposition voltage. As a result, this material is prone to Li dendrite formation, which is a safety hazard during charging and discharging.…”