A Unique Structural Highly Compacted Binder‐Free Silicon‐Based Anode with High Electronic Conductivity for High‐Performance Lithium‐Ion Batteries

Abstract

Herein, a unique structural Si‐based anode with high electronic conductivity, high compact density, and with no traditional organic binder is put forward. By adding a few amounts of Sn to the Si anode material, followed by carbonization of the organic binder after the general anode preparation and subsequently hot pressing, Sn melts and squeezes during hot pressing, bonding strongly the Si particles, and an interlayer of Cu3Si/Cu3Sn is in situ formed at the interface of the Si‐based active materials and the Cu current collector, resulting in a metallurgical bonding between them. The organic binder‐derived carbon coats on the Si particles, coupling with the squeezed Sn and the Cu3Si/Cu3Sn interlayer, and a highly electron conductive skeleton is formed. The skeleton also offers a highly stable structural integrity of the electrode during cycling. With an optimization of the hot‐pressing pressure, the Si‐based anode shows superior cycling stability and rate performance. As the active materials are almost compacted to half of its initial thickness, the electrode has potential for high volumetric capacity. The fabrication method is new for Si‐based anodes of high compact density. The work provides new insights into the development of advanced silicon‐based anodes for lithium‐ion batteries.

Chemically Binding Vanadium Sulfide in Carbon Carriers to Boost Reaction Kinetics for Potassium Storage

“…To further confirm the efficient charge-transfer kinetics of CB-VS@NSCNFs, electrochemical impedance spectroscopy (EIS) measurements were performed. The Nyquist plot consists of a semicircle (charge-transfer resistance ( R ct )) in the high-frequency region and a slash (K + diffusion resistance) in the low-frequency region. − The semicircle of CB-VS@NSCNFs (365 Ω) is smaller than that of B-VS/C (400 Ω), indicating that the charge transfer at the interface of CB-VS@NSCNFs is significantly faster than that of B-VS/C (Figure e). Moreover, the corresponding Z′ –ω –1/2 curves for the low-frequency region are depicted in Figure f.…”

Advances in the Development of Single‐Atom Catalysts for High‐Energy‐Density Lithium–Sulfur Batteries

“…whereas the reverse process occurs during discharge. [6][7][8][9][10] Since the commercialization of LIBs, their practical energy density has increased from 150 to 300 Wh kg −1 and is currently close to the theoretical value of 420 Wh kg −1 (1400 Wh L −1 ), which results in a development bottleneck. [11][12][13] As the theoretical energy density of LIBs is still insufficient for some applications, for example, electric vehicles, novel energystorage systems with elevated energy densities and cycling lifetimes are highly sought after.…”

Research Progress on the Structural Design and Optimization of Silicon Anodes for Lithium-Ion Batteries: A Mini-Review

“…The presence of a carbon skeleton prevents cracked silicon particles from falling off and maintains good electrical contact. Dong et al [46] added a small amount of Sn to the slurry to carbonize the original binder into a conductive skeleton. Sn was melted and extruded by hot pressing and was cooled to bond Si particles.…”