High Molecular Weight Polyacrylonitrile Precursor for S@pPAN Composite Cathode Materials with High Specific Capacity for Rechargeable Lithium Batteries

Abstract

Sulfurized pyrolyzed poly(acrylonitrile) (S@pPAN) demonstrates high sulfur utilization, no polysulfide dissolution, no self-discharge, and extremely stable cycling. Its precursor, PAN, directly determines the performances of cathode materials, including the sulfur content and its utilization for S@pPAN composite materials. Adopting PAN with the molecular weight approaching 550,000 as the precursor, the sulfur content in S@pPAN approaches 55 wt %, and its reversible specific capacity was 901 mAh g −1 (composite) at 50 °C with sulfur utilization over 98%. Moreover, it enabled stable cycling and excellent high rate capability with a specific capacity of 645 mAh g −1 at 5 C. These significantly enhanced electrochemical properties are mainly due to the high molecular weight of the PAN precursor, which provides more space to accommodate amorphous sulfur, along with improved interfacial resistance of S@pPAN.

Stabilizing intermediate phases via the efficient confinement effects of the SnS2-SPAN fibre composite for ultra-stable half/full sodium/potassium-ion batteries

“…24,62 Two oxidation peaks related to the generation of the dealloying reaction and the inverse procedure of the conversion reaction, as well as the formation of SPAN were discerned at 1.3 and 1.91 V in the initial positive sweep, respectively. 30,63 Other CV curves for the initial three cycles, including SnS 2 -SPAN-470-2, SnS-CNF-700, pure SPAN-470 and pure SnS 2 electrodes, were compared with that of the SnS 2 -SPAN-470-1 electrode in Fig. S4.…”

Overview of the Latest Developments and Perspectives about Noncarbon Sulfur Host Materials for High Performance Lithium–Sulfur Batteries

“…In recent years, some research groups have used the composite materials formed by the reaction of PAN , and sulfur under certain conditions as the cathode of Li–S batteries, which can greatly improve the chemical activity of elemental sulfur and improve the conductivity of elemental sulfur electrodes. So, the Coulombic efficiencies and cycle stabilities of cathodes can be greatly improved.…”

“…In recent years, some research groups have used the composite materials formed by the reaction of PAN 155,156 and sulfur under certain conditions as the cathode of Li−S 4.5. Other Polymers.…”

Pinned Electrode/Electrolyte Interphase and Its Formation Origin for Sulfurized Polyacrylonitrile Cathode in Stable Lithium Batteries

“…21−23 This is supported by the significantly diminished lifespan of Li||SPAN cells with high SPAN loading compared to that with low SPAN loading (Table S1), overshadowing the advantages of carbonate-based electrolytes toward SPAN cathodes. 24,25 Therefore, it is much more stringent to develop favorable electrolytes for high loading SPAN when aiming to maximize the energy density of Li−S batteries.…”