电池型电容器的正极结构设计与性能  

Structure design and performance of cathode for battery-type capacitor

作　　者：田洪松 刘富亮 周雄 袁东 石斌 袁再芳 TIAN Hongsong;LIU Fuliang;ZHOU Xiong;YUAN Dong;SHI Bin;YUAN Zaifang(State Key Laboratory of Advanced Chemical Power Sources,Guizhou Meiling Power Sources Co.,Ltd.,Zunyi,Guizhou 563003,China)

机构地区：[1]贵州梅岭电源有限公司,特种化学电源全国重点实验室,贵州遵义563003

出　　处：《电池》2024年第6期836-840,共5页Battery Bimonthly

基　　金：贵州省科技厅中央引导地方科技发展资金项目(黔科合中引地[2024]008)。

摘　　要：电池型电容器正极材料在涂覆干燥时,会因表面张力导致出现电极界面不稳定、极片电阻率偏大及孔隙率分布不均匀等问题。以高电压钴酸锂(LiCoO_(2))为正极材料,采用多层涂覆技术对LiCoO_(2)正极片进行厚度梯度设计。控制双层涂覆极片的总厚度为30μm,调节双层极片的厚度梯度分布,实现极片上下层孔隙率的差异化分布,构造Li^(+)快速传输通道,减小离子扩散阻力、减缓容量衰减。与具有各向异性和高层间距的硬碳(HC)负极组装成软包装电池型电容器,进行电化学性能测试。双层电极LH-18(第一层涂覆厚度为18μm)首次循环的库仑效率达到80.85%,比单层电极(LH-30)高6.27个百分点。在2.5~4.2 V循环,20.00 C的放电容量为1.00 C时的81.82%,1.00 C充放电100%放电深度(DOD)循环3 509次后,容量保持率仍有80%,循环次数是单层电极(LH-30)的2.27倍。When the cathode material of battery-type capacitors is coated and dried,the surface tension will lead to the instability of the electrode interface,the large resistivity of the pole piece and the uneven distribution of porosity.High-voltage lithium cobalt oxide(LiCoO_2) is used as the cathode material,the thickness gradient design of the LiCoO_(2) cathode plate is carried out by using multi-layer coating technology.By controlling the total thickness of the double-layer coated electrode plates to 30 μm,the thickness gradient distribution between the double-layer electrode plates is adjusted,the differential distribution of porosity between the upper and lower layers of the electrode plates is realized,the rapid transmission channel of Li^(+) is constructed to reduce ion diffusion resistance and slow capacity attenuation.A pouch battery-type capacitor is assembled with a hard carbon(HC) anode with anisotropy and high space,its electrochemical performance is tested.The Coulombic efficiency in the initial cycle of the two-layer electrodes LH-18(the thickness of the first layer is 18 μm) reaches 80.85%,which is 6.27 percentage points higher than the single-layer electrode(LH-30).When cycled in 2.5-4.2 V,the discharge capacity at 20.00 C is 81.82% of that at 1.00 C.After 3 509 cycles of 100% depth of discharge(DOD) at 1.00 C,the capacity retention rate is still 80%,the cycle number is 2.27 times than that of the single-layer electrode(LH-30).

关 键 词：电池型电容器 钴酸锂(LiCoO_(2)) 硬碳 多层涂覆 

分 类 号：TM533[电气工程—电器] TM912.9