A Robust Solid Electrolyte Interphase Layer Augments the Ion Storage Capacity of Bimetallic‐Sulfide‐Containing Potassium‐Ion Batteries

Abstract

Metal-organic framework-derived NiCo 2.5 S 4 microrods wrapped in reduced graphene oxide (NCS@RGO) were synthesized for potassium-ion storage.Upon coordination with organic potassium salts,N CS@RGO exhibits an ultrahigh initial reversible specific capacity (602 mAh g À1 at 50 mA g À1 ) and ultralong cycle life (a reversible specific capacity of 495 mAh g À1 at 200 mA g À1 after 1900 cycles over 314 days). Furthermore,t he battery demonstrates ah igh initial Coulombic efficiency of 78 %, outperforming most sulfides reported previously.A dvanced ex situ characterization techniques,i ncluding atomic force microscopy, were used for evaluation and the results indicate that the organic potassium salt-containing electrolyte helps to form thin and robust solid electrolyte interphase layers,w hichr educe the formation of byproducts during the potassiation-depotassiation process and enhance the mechanical stability of electrodes.T he excellent conductivity of the RGO in the composites,a nd the robust interface between the electrodes and electrolytes,i mbue the electrode with useful properties;i ncluding,u ltrafast potassium-ion storage with areversible specific capacity of 402 mAh g À1 even at 2Ag À1 .

K‐Ion Storage Enhancement in Sb2O3/Reduced Graphene Oxide Using Ether‐Based Electrolyte

“…However, with the rapid growth of renewable energy sources and smart grid, the development of LIBs has suffered enormous restriction due to high cost and low earth‐abundance of Li element . Therefore, alternatives based on earth‐rich elements for energy storage system including Na‐ion batteries (NIBs) and biocompatible battery attract much attention . Currently, NIBs have become a research hotspot due to the high abundance of Na element in earth .…”

The Features and Progress of Electrolyte for Potassium Ion Batteries

“…These results indicate that the effect of FEC on K‐ion battery is different from that of Li/Na ion battery. [ 8 ]…”

“…At present, K‐ion batteries are still in its infancy. Anode materials of K‐ion batteries are mainly focus on carbon‐based materials, [ 8–10 ] alloy negative [ 11,12 ] and K metal anode (or Na–K alloy anode) [ 13,14 ] (Figure 1c). For anode materials, it is still a challenge to inhibit the formation of potassium dendrites and build a stable electrode/electrolyte interface in K‐ion batteries.…”

Covalent Organic Frameworks for Next‐Generation Batteries

“…Most inorganic electrode materials have excellent performances in LIBs and SIBs, but the electrochemical performance of PIBs is not very remarkable. [56,57] Unlike inorganic electrode materials, organic electrode materials can provide more active sites and transmission channels for potassium storage due to their good structural adjustability and openpore channels. Therefore, organic electrode materials are one potential candidate electrode materials for high-performance PIBs.…”