Water Reducer: A Highly Dispersing Binder for High‐Performance Lithium‐Sulfur Batteries^†

Abstract

Energy conversion| Polymers | Binder | Polyanions| AdsorptionSulfur has been paid close attention by the research and manufacturing as a cathode material for lithium-sulfur batteries (LSB) in recent decade because it has high specific capacity and low cost. But the low utilization of active materials and serious shuttle phenomenon inhibit its commercialization process. In this work, for the first time, water reducers are reported as multifunctional binders to address the above problems to enhance the performance of LSB. Due to the synthetic actions of the water reducer binder, such as highly dispersing effect and good chemical trapping function, commercial sulfur powders are directly used as cathodes, and much better electrochemical performance compared to using the conventional binder polyvinylidene fluoride (PVDF) was obtained, among which the sulfur cathode with sulfonated melamine formaldehyde (SMF) water reducer binder exhibits a high reversible capacity of 625.5 mA•h•g -1 after 200 cycles at 1 C and the cathode with polycarboxylic acid (PC) water reducer binder even demonstrates a high area specific capacity of 5 mA•h•cm -2 at high sulfur loading of 5 mg•cm -2. These low-cost water reducers are a promising binder for LSB in the future.

Highly branched amylopectin binder for sulfur cathodes with enhanced performance and longevity

“…Depressed semi‐circles in the high‐ to medium‐frequency region of the spectra can be observed, which can be attributed to the electrolyte resistance ( R e ), charge transfer resistance ( R ct ), and interface/solid electrolyte interface resistance ( R int ), respectively. [ 79 ] As the S/HBA cell displays lower resistances in all cases (Table 1), it can be inferred that the HBA better maintains the conductive carbon network after cycling compared to when PVDF or LBP is used as a binder. The linear portion of the curve in the low‐frequency region of Figure 4C can be attributed to the Warburg ( W O ) impedance in the cells.…”

Research progress on lignin-based carbon electrode materials in rechargeable batteries

“…Most portable devices on the market use lithium-ion batteries, which are the mainstream energy storage system in modern society. The low-energy density is a bottleneck for large-scale applications (Geng et al 2021). Following lithium-ion batteries, lithium-sulfur batteries have received very widespread attention, because they can provide higher theoretical energy density by weight (2500 Wh/kg) and energy density by volume (2800 Wh/L), as well as a capacity that is an order of magnitude higher than that of conventional lithium-ion batteries (1675 mAh/g) (Yeon et al 2020).…”

Highly Stretchable and Elastic Polymer Electrolytes with High Ionic Conductivity and Li‐Ion Transference Number for High‐Rate Lithium Batteries

“…[ 7‐20 ] As the electrolyte is one of the key components in LIBs, intrinsically stretchable polymer electrolytes (PEs) with satisfactory mechanical robustness are highly required for the fabrication of stretchable LIBs. [ 21‐28 ] From the perspective of practical applications, the stretchable PEs are expected to endow the stretchable LIBs with fast charging capability to minimize the charging time of wearable devices. [ 29‐31 ] Specifically, the charging/discharging speed of LIBs is usually evaluated by their rate performance and thus fast charging capability requires the LIBs to be operated at a high rate.…”