储能科学与技术2025，Vol.14Issue(4)：1331-1339,9.DOI:10.19799/j.cnki.2095-4239.2024.0988
多功能电解液添加剂2,6-吡啶二甲腈稳定高电压钴酸锂
2,6-pyridine dimethyl acetonitrile:A multifunctional electrolyte additive for stabilizing high-voltage LiCoO2
摘要
Abstract
To address the rapid degradation of high-voltage lithium cobalt oxide(LCO)performance caused by crystal structure deterioration and intensified side reactions,this study introduces a novel multifunctional electrolyte additive,2,6-pyridinitrile(DCPY),to enhance electrode/electrolyte interface stability.The electrode interface,electrolyte physical properties,and electrochemical characteristics of the battery are analyzed using scanning electron microscopy,transmission electron microscopy,electrochemical techniques,and theoretical calculations.The findings reveal that as a multifunctional electrolyte additive,DCPY forms a highly stable interfacial film on both positive and negative electrodes,effectively suppressing electrode/electrolyte interface side reactions and preventing the dissolution and deposition of transition metals.Additionally,the pyridine functional groups in DCPY interact with phosphorus pentafluoride in the electrolyte,substantially reducing corrosion caused by hydrofluoric acid(HF)at both electrode interfaces.This interaction enhances the high-voltage stability of commercial LCO pouch cells.As a result,adding 0.5%DCPY to the base electrolyte solution(Base)optimizes cycling performance in commercial pouch cells(Base+DCPY),increasing capacity retention from 80%to 90%after 800 cycles at 25℃and from 80%to 85%after 600 cycles at 45℃.Furthermore,DCPY substantially mitigates gas generation issues during high-temperature operation.Even at an increased operating voltage of up to 4.55 V,LCO//Gr(graphite)pouch cells maintain excellent cycling stability under elevated temperatures.This study presents a practical strategy for developing high-voltage energy storage batteries with high energy density.关键词
锂离子电池/钴酸锂/高电压/电解液添加剂/2,6-吡啶二甲腈Key words
lithium ion battery/lithium cobalt oxide/high voltage/electrolyte additive/2,6-pyridinedicarbonamide分类
信息技术与安全科学引用本文复制引用
廖兴群,杨睿,于立娟,胡大林,肖峰,胡菁,卢周广..多功能电解液添加剂2,6-吡啶二甲腈稳定高电压钴酸锂[J].储能科学与技术,2025,14(4):1331-1339,9.基金项目
粤港澳联合创新基金(2024A0505040001),国家自然科学基金(92372114),广东省基础与应用基础研究基金惠州市联合基金地区培育项目(2023A1515140096),广东省基础与应用基础研究基金(2023A1515010035). （2024A0505040001）
