新型CF_(x)锂原电池自放电率的比较研究及其应用建议  

Comparative study on self-discharge rate of new CF_(x) lithium primary batteries and recommendations for their use

作　　者：杨微 李治国 赖彩婷 赵瑞瑞 李瑀[2] 周盈科[3] 黄依玲 朱立才[4] 封伟[2] 王文龙[5] 袁中直[4] YANG Wei;LI Zhiguo;LAI Caiting;ZHAO Ruirui;LI Yu;ZHOU Yingke;HUANG Yiling;ZHU Licai;FENG Wei;WANG Wenlong;YUAN Zhongzhi(EVE Energy Co.Ltd,Huizhou 516006,Guangdong,China;School of Materials Science and Engineering,Tianjin University,Tianjin 300072,China;The State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China;School of Chemistry,South China Normal University,Guangzhou 510006,Guangdong,China;Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China)

机构地区：[1]惠州亿纬锂能股份有限公司,广东惠州516006 [2]天津大学材料科学与工程学院,天津300072 [3]武汉科技大学省部共建耐火材料与冶金国家重点实验室,湖北武汉430081 [4]华南师范大学化学学院,广东广州510006 [5]中国科学院物理研究所,北京凝聚态物理国家研究中心,北京100190

出　　处：《储能科学与技术》2024年第11期3742-3753,共12页Energy Storage Science and Technology

摘　　要：新型高比能氟化碳(CF_(x))材料不断涌现,使Li/CF_(x)原电池的比能量/比功率特性持续提升,特别是功率型Li/CF_(x)电池已开始用于小型商业化动力系统中,可能成为比能量最高的动力型锂原电池。但不同类型CF_(x)材料制备的Li/CF_(x)锂原电池的自放电情况尚缺乏比较研究。本文选择4种典型的新型CF_(x)材料,根据其应用目标分为能量型和功率型材料,其中2种能量型CFx的F/C比接近1,具有更稳定而饱和的C—F化学键,而2种功率型CF_(x)材料F/C比略低,离子型C—F键更多,具有更好的导电性和更好的倍率性能。通过工业化设备工艺制备成的BR18650型Li/CF_(x)原电池经55℃高温储存后,无论是否放电过,能量型电池的自放电率几乎为0,具有长寿命货架储存特性;而功率型电池55℃储存后,放电深度(DOD)越高的电池的内阻越大、自放电率也越大,锂原电池常用的预放电处理工艺会导致功率型电池的自放电率上升,意味着功率型电池一旦预放电激活后就应立即投入使用。功率型电池间歇式使用会导致其自放电率增大和内阻增加,原因可能是松散LiF保护膜的破坏造成新鲜CF_(x)界面暴露于电解液中继续反应,但能量型CF_(x)材料因其具有更多稳定的饱和C—F共价键而影响较小。The emergence of new high specific energy fluorinated carbon(CF_(x))materials has continuously improved the specific energy/specific power characteristics of Li/CF_(x) primary batteries,especially the power type Li/CF_(x) batteries have begun to be used in small commercial power systems and may become the power type lithium primary batteries with the highest specific energy.However,there is a lack of comparative study on the self-discharge of Li/CF_(x) lithium primary batteries prepared from different types of CF_(x) materials.This article selects four typical novel CF_(x) materials that are divided into energy type and power type materials according to their applications,among which two energy type CF_(x) materials have F/C ratios close to 1 and more stable and saturated C-F chemical bonds,while two power type CF_(x) materials have lower F/C ratios and more ionic C-F bonds,resulting in better conductivity and rate performance.After being stored at a high temperature of 55℃,the self-discharge rate of the industrially prepared BR18650 Li/CF_(x) battery,regardless of whether it has been discharged or not,is almost zero,making it suitable for long-life shelf storage.However,for power batteries stored at 55℃,the higher the depth of discharge(DOD),the greater the internal resistance and self-discharge rate of the battery.The pre-discharge treatment that is commonly used in lithium primary battery industry can lead to an increase in the self-discharge rate of power type batteries,which means that power type batteries should be put into use immediately after pre-discharge activation.Intermittent use of power type batteries can lead to an increase in their self-discharge rate and internal resistance,which may be due to the damage of the loose LiF protective film causing the fresh CF_(x) interface to be exposed to the electrolyte and continuous reaction,but the energy type CF_(x) material has less impact due to its more stable saturated C-F covalent bonds.

关 键 词：锂/氟化碳电池 原电池 自放电率 

分 类 号：TM911[电气工程—电力电子与电力传动]