"Peapod-like" Fiber Network: A Universal Strategy for Composite Solid Electrolytes to Inhibit Lithium Dendrite Growth in Solid-State Lithium Metal Batteries.

Solid-state lithium metal batteries (SSLMBs) are a promising energy storage technology, but challenges persist including electrolyte thickness and lithium (Li) dendrite puncture. A novel three-dimensional "peapod-like" composite solid electrolyte (CSEs) with low thickness (26.8 µm), high mechanical strength, and dendrite inhibition was designed. Incorporating Li7La3Zr2O12 (LLZO) enhances both mechanical strength and ionic conductivity, stabilizing the CSE/Li interface and enabling Li symmetric batteries to stabilize for 3000 h. With structural advantages, the assembled LFP||Li and NCM811||Li cells exhibit excellent cycling performance. In addition, the constructed NCM811 pouch cell achieves a high gravimetric/volumetric energy density of 307.0 Wh kg-1/677.7 Wh L-1, which can light up LEDs under extreme conditions, demonstrating practicality and high safety. This work offers a generalized strategy for CSE design and insights into high-performance SSLMBs.

3D flower-like hollow MXene@MoS2 heterostructure for fast sodium storage.

Constructing an anode with fast electron transport and high cycling stability is important but challenging for large-scale applications of sodium-ion batteries (SIB). In this study, hierarchical flower-like MXene structures were synthesized using poly (methyl methacrylate) (PMMA) microsphere as templates. Subsequently, a straightforward hydrothermal reaction was utilized to anchor small-sized MoS2 nanosheets. The resulting MXene@MoS2 heterostructure exhibits a distinctive three-dimensional (3D) porous hollow architecture. This structure effectively addresses challenges related to self-aggregation of MoS2 nanosheets and volume expansion of the electrode material during Na+ insertion/extraction processes. Furthermore, the robust hetero-interface supports fast and stable electron transfer, thereby enhancing electrochemical reaction kinetics. The prepared MXene@MoS2 electrode demonstrates the specific capacity of 682.1 mA h g-1 at 0.2 A/g and the reversible capacity of 494.4 mA h g-1 after 1000 cycles at 5 A/g. It is noteworthy that the full battery assembled with the composite material as the anode can still maintain the capacity of 456.2 mA h g-1 after 80 cycles at 0.5 A/g. This outstanding reversible capacity and sustained stability over numerous cycles highlights its potential for a wide range of applications.