Graphical Abstract
Li-Ion Batteries
In article number 2500131, Asif Latief Bhat and Yu-Sheng Su illustrate the sponge-like structural evolution of silicon anode particles during cycling, which coincides with the onset of Coulombic efficiency troughs. The study identifies key factors such as electrode thickness, voltage window, and electrolyte composition that govern this phenomenon, providing new insights to guide the design of stable and high-performance silicon-based lithium-ion batteries.
Achieving smooth and dendrite-free lithium deposition is critical for the commercialization of lithium metal batteries (LMBs). This study explores the role of silver salts (AgNO3, AgF, AgCl, Ag2CO3, and Ag2SO4) in regulating lithium nucleation and solid–electrolyte interphase (SEI) stability. Upon in situ reduction under lithiation conditions, silver ions form a uniform metallic Ag layer that serves as a highly lithiophilic nucleation seed, significantly lowering the plating overpotential and promoting dense lithium growth. Concurrently, the dissociated anions contribute to SEI formation, influencing interfacial stability and lithium-ion transport. Electrochemical characterizations reveal that AgNO3-coated substrate achieves near-100% Coulombic efficiency, the lowest nucleation overpotential, and superior cycling stability compared to other silver salts. Advanced lithium-sensitive energy-dispersive X-ray spectroscopy mapping confirms the uniform distribution of lithium and silver, correlating with the enhanced lithium plating reversibility. X-ray photoelectron spectroscopy and X-ray diffraction further validate the formation of a stable Li–Ag alloy and a Li3N-enriched SEI, which collectively suppress dendrite formation and improve interfacial stability. These findings establish AgNO3-coated current collector as a promising and scalable strategy for high-performance LMBs, providing new insights into interface engineering for next-generation energy storage systems.
The development of high-performance lithium‒sulfur batteries (LSBs) has been focused on overcoming the limitations associated with traditional polysulfide catholyte synthesis. We report an innovative catholyte synthesis method using lithium-arene complexes, offering significant advancements in terms of solubility, stability, and scalability. By leveraging the interaction of metallic lithium with biphenyl (BP) and sulfur, we develop a Li+BP+S catholyte formulation that outperforms conventional Li2S+S systems. The Li+BP+S catholyte demonstrates superior solubility, achieving up to 12 M active sulfur and faster dissolution rates at lower temperatures, reducing preparation times by 66%. Electrochemical evaluations revealed enhanced capacity retention, with the catholyte maintaining 83.2% of its initial capacity after 500 cycles and exhibiting minimal capacity fading of 0.03% per cycle. Material characterization confirmed a uniform sulfur distribution, improved charge transfer capability, and reduced polysulfide clustering, as evidenced by NMR, SEM, and XPS analyses. The Li+BP+S system also demonstrated high-rate capability and long-term stability, retaining significant capacity under lean electrolyte conditions. The mechanism by which the addition of arenes aides Li dissolution is also proposed on the basis of theoretical calculations. These findings highlight the potential of lithium–arene complexes to revolutionize LSB technology, paving the way for safer, more efficient, and scalable LSB systems.
