Three‐Component Functional Additive in a LiPF₆‐Based Carbonate Electrolyte for a High‐Voltage LiCoO₂/Graphite Battery System

Abstract

The effectiveness of multicomponent functional additives on the performances of lithium ion batteries has received increasing attention. Tris(2H‐hexafluoroisopropyl) borate (THFPB) additive can totally suppress the appearance of a crystallized complex between LiPF6 and adiponitrile (ADN). Herein, ADN, THFPB, and cyclohexylbenzene are demonstrated to be an effective three‐component functional additive in LiPF6‐based carbonate electrolyte that improves the cyclability and rate capabilities of LiCoO2/graphite full cells charged to 4.4, 4.45, and 4.5 V, respectively. By systematic characterization, it is demonstrated rationally that, with the help of the three‐component functional additive, the electrolyte is stabilized and new types of less resistant, thinner, more protective solid–electrolyte interfaces are constructed simultaneously on the surfaces of both electrodes.

Stabilizing electrode–electrolyte interfaces to realize high-voltage Li||LiCoO2 batteries by a sulfonamide-based electrolyte

“…5,9,15,17,[19][20][21][22][23] An alternative strategy is to develop highly compatible electrolytes to form stable CEIs. Although fluorinated electrolytes, 24,25 multifunctional polymer electrolyte, 26,27 and additives 28,29 have demonstrated promising cyclability improvement, such explorations have been focused mainly on charging voltages up to 4.5 V Li 24,25,30 (Table S1, ESI †). It still remains challenging to design suitable electrolytes for higher-voltage (44.5 V Li ) LCO.…”

A Shape Memory High‐Voltage Supercapacitor with Asymmetric Organic Electrolytes for Driving an Integrated NO2 Gas Sensor

“…The peaks at 760, 1092, and 1254 cm −1 are attributed to the bending vibration of OH, CH deformation vibration, and ester CO asymmetric stretching, respectively . The peaks at 1519, 1750, and 2274 cm −1 result from the skeletal vibration of benzene, vibration of CO, and NC group, respectively . All of the peaks from the individual components are observed from the electrolytes with HQ and DHQ, respectively, indicating the uniform mixing of all of components in the electrolytes.…”

Improved electrochemical performance of a LiCoO2/MCMB cell by regulating fluorinated electrolytes

“…The minor redox peaks around 4.1–4.2 V are caused by the order–disorder phase transformation between hexagonal and monoclinic phases. 25 Besides, a pair of obvious redox peak appears at high voltage region beyond 4.4 V, which stands for another phase transition in LCO and produces extra capacity. 8 These characteristic peaks are well recorded in the charge–discharge profiles of Fig.…”