Unlocking high capacities of graphite anodes for potassium-ion batteries

Abstract

Ball-milling of graphite results in graphene layer exfoliation and defect formation, leading to enhanced performance as a K-ion battery anode.

State-of-the-art anodes of potassium-ion batteries: synthesis, chemistry, and applications

“…24b . 23 Although the anodes exhibited a high initial potassiation capability of 345 mA h g −1 , an obvious capacity jump was observed within 20 cycles, and the coulombic efficiency underwent severe fluctuations after 100 cycles, making it impossible to fabricate a reliable practical full cell.…”

Strategies for Mitigating Dissolution of Solid Electrolyte Interphases in Sodium‐Ion Batteries

“…The instability of the electrode‐electrolyte interfacial layers is one of the main sources of ageing in SIBs. As most non‐aqueous electrolytes are unstable at the electrochemical potentials of the negative electrodes, the formation of a stable passivation layer known as the solid electrolyte interphase (SEI) is both unavoidable and essential [1, 6, 7] …”

“…As most non-aqueous electrolytes are unstable at the electrochemical potentials of the negative electrodes,the formation of as table passivation layer known as the solid electrolyte interphase (SEI) is both unavoidable and essential. [1,6,7] In the ideal case,the SEI, which mainly is formed on the first charge/discharge cycle,i se lectronically insulating, impermeable to the solvent molecules to avoid continuous electrolyte decomposition, and ionically conducting to allow the migration of Na + ions.I na ddition, the SEI should be insoluble and inert with respect to the electrolyte to avoid parasitic reactions resulting in irreversible capacity losses. [8][9][10][11] Compared to in LIBs,t he SEIs formed in Na-based electrolytes are often reported to be less stable due to the higher solubilities of the SEI components.…”

Boosting Li/Na storage performance of graphite by defect engineering

“…The unfavorable mismatching of the graphite layer distance and the Na-ion diameter are generally considered to be a main reason for the low sodium storage capacity in graphite by forming a kind of low Na content graphite intercalation compound, namely NaC64. [21][22][23][24][25][26] Encouragingly, in recent studies, researchers successfully increased the sodium storage capacity in graphite by expanding the layer space. 15,27 Adelhelm et al used a solvent-Na-ion co-intercalation into the graphite method to expand the graphite interlayer space, which can achieve a capacity of 130 mA h g À1 at the current density of 20 mA g À1 in a diglyme-based electrolyte.…”