乙二醇双(丙腈)醚对高电压锂离子电池的影响

用线性扫描伏安(LSV)和电化学阻抗谱(EIS)研究乙二醇双(丙腈)醚(DENE)作为锂离子电池电解液添加剂的电化学行为;对电极表面形貌和元素进行SEM和X射线能谱(EDS)分析;对钴酸锂(LiCoO_2)正极进行XRD分析;考察DENE对4.45 V高电压LiCoO_2锂离子电池的影响。DENE能在高温环境下抑制正极过渡金属溶出、保护负极固体电解质相界面膜,电池60℃存储30 d的厚度膨胀率从76.8%下降到12.3%,以0.50 C在55℃下循环(3.00~4.45 V)200次,容量保持率从58.5%提高到86.3%。

Effect of ethylene glycol bis (propionitrile) ether on high-voltage Li-ion battery

The electrochemical behaviors of ethylene glycol bis (propionitrile) ether (DENE) as an additive in electrolyte Li-ion battery were studied by linear sweep vohammetry (LSV) and electrochemical impedance spectroscopy (EIS).The surface morphology and elements distribution at the surface of electrodes were analyzed by SEM and X-ray energy spectrometer (EDS).The effect of DENE on 4.45 V high-voltage LiCoO2 Li-ion battery was investigated.The lithium cobalt oxide was analyzed by XRD.The dissolution of transition metal from cathode was inhibited and the SEI film on anode surface was stabilized by DENE,especially at high temperature,leading to the swelling decreased from 76.8％ to 12.3％ after storing at 60 ℃ for 30 d,the capacity retention ratio after 200 cycles(3.00-4.45 V) at 55 2 increased from 58.5 ％ to 86.3 ％.