Epoxidized Natural Rubber/Chitosan Network Binder for Silicon Anode in Lithium-Ion Battery

Abstract

Polymeric binder is extremely important for Si-based anode in lithium-ion batteries due to large volume variation during charging/discharging process. Here, natural rubber-incorporated chitosan networks were designed as a binder material to obtain both adhesion and elasticity. Chitosan could strongly anchor Si particles through hydrogen bonding, while the natural rubber could stretch reversibly during the volume variation of Si particles, resulting in high cyclic performance. The prepared electrode exhibited the specific capacities of 1350 mAh/g after 1600 cycles at the current density of 8 A/g and 2310 mAh/g after 500 cycles at the current density of 1 A/g. Furthermore, the cycle test with limiting lithiation capacity was conducted to study the optimal binder properties at varying degree of the volume expansion of silicon, and it was found that the elastic property of binder material was strongly required when the large volume expansion of Si occurred.

A Facile Strategy to Construct Silver‐Modified, ZnO‐Incorporated and Carbon‐Coated Silicon/Porous‐Carbon Nanofibers with Enhanced Lithium Storage

“…Among them, Si‐based materials have received considerable attention due to their superior features in terms of natural abundance, nontoxicity, low working potential, and the highest theoretical capacity of 4200 mA h g −1 . However, Si‐based anodes suffer from the drawbacks of large volumetric change and poor electronic conductivity, resulting in material pulverization and electrical disconnection, and further leading to cycling capacity decay . In the past years, great research efforts have been made to circumvent the above problems and realize the practical application.…”

“…During alloying/dealloying process, the expansion and shrinkage of Si anodes during cycling would have a bad contraction stress, making the crack and stripping of Si active materials. Meanwhile, the solid electrolyte interphase (SEI) films will form successively and become thicker caused by continuous volumetric deformation of Si anode, leading to the decomposition and loss of electrolyte, large ionic transport resistance, and finally causing the failure of Si anodes . Three main strategies have since been adopted to solve volume change for Si anodes.…”

Poly(siloxane imide) Binder for Silicon‐Based Lithium‐Ion Battery Anodes via Rigidness/Softness Coupling

“…The results confirm that the elasticity of the PSI/Si electrode is enhanced compared to the PI/Si electrode, which is helpful to mitigate mechanical stress and restore deformation upon lithiation and delithiation. [28][29][30] In addition, the PI block itself within the PSI binder is still stiff. As a result, the capability to withstand the local mechanical stress by the PI block still exisits.…”

Sustainable Battery Materials from Biomass

“…Furthermore, functionalized chitosan‐based binders with different carboxylate or amide side chains were introduced. Crosslinking of chitosan chains was shown to increase stability, and grafting natural rubber as side chains helped to increase flexibility …”