Rechargeable Batteries with High Energy Storage Activated by In-situ Induced Fluorination of Carbon Nanotube Cathode

Abstract

High performance rechargeable batteries are urgently demanded for future energy storage systems. Here, we adopted a lithium-carbon battery configuration. Instead of using carbon materials as the surface provider for lithium-ion adsorption and desorption, we realized induced fluorination of carbon nanotube array (CNTA) paper cathodes, with the source of fluoride ions from electrolytes, by an in-situ electrochemical induction process. The induced fluorination of CNTA papers activated the reversible fluorination/defluorination reactions and lithium-ion storage/release at the CNTA paper cathodes, resulting in a dual-storage mechanism. The rechargeable battery with this dual-storage mechanism demonstrated a maximum discharging capacity of 2174 mAh gcarbon−1 and a specific energy of 4113 Wh kgcarbon−1 with good cycling performance.

Graphene-wrapped mesoporous MnCO3 single crystals synthesized by a dynamic floating electrodeposition method for high performance lithium-ion storage

“…32 Their low tap density also results in a low volumetric energy density. Although nanometer-size active materials have demonstrated improved performance when normalized to the weight of active materials only, these nanomaterials require a high percentage of conductive and binding materials in the electrodes, normally over 20 wt% in total, sacrificing the final performance of the full cell.…”

“…Although nanometer-sized active materials have demonstrated an improved performance when normalized to the weight of active materials only, these nanomaterials require a high percentage of conductive and binding materials in the electrodes, normally over 20 wt% in total, sacricing the nal performance of the full cell. 32 Their low tap density also results in a low volumetric energy density. 33 In this sense, the structure of submicron, graphene-wrapped MSCs is an ideal structure to be used as active materials in LIBs, since it adopts the advantages of high tap density from microparticles, large tolerance to volume expansion from mesoporosity, and high conductivity from graphene.…”

Boosting the Energy Density of Li||CFx Primary Batteries Using a 1,3-Dimethyl-2-imidazolidinone-Based Electrolyte

“…In spite of the highest specific capacity of 922.6 mAh g –1 of fluorinated hard carbon obtained at 390 °C, the sacrificial discharge potential is about 0.15 V compared with that fluorinated at 350 °C, which limited the improvement of energy density. Besides, nanostructured precursors were introduced for CF x materials, such as carbon nanotubes, − carbon nanodiscs, graphite nanosheets, graphene, , and graphene oxide, to shorten the lithium-ion transportation distance and improve molecular wettability through size effects. This strategy is instrumental for the improvement of the rate performance of CF x cathodes but sacrifices the volumetric energy density owing to the high specific surface area and low electrode density of nanostructured CF x materials.…”

Controlling Fluoride‐Forming Reactions for Improved Rate Capability in Lithium‐Perfluorinated Gas Conversion Batteries

“…[20] Notably, such strategies are not unique to metal-gas systems, and have been employed as well in solid-solid conversion reactions, for instance to mediate the passivating effects of bulk LiF formation in Li-CF x batteries. Strategies, including optimizing electrolyte solvents (for example using dimethyl sulfoxide (DMSO)), [21] and incorporating electrolyte additives (such as anion receptors), [22] has been applied to improve the Li-CF x battery performance significantly by promoting fluoride solvation.…”