纳米Bi的制备及其在锂离子电池中的应用研究  

Preparation of nano-Bi and its application in lithium-ion batteries

作　　者：王启明 陈卓[2] 陈远强[2] 陈素晶[2] 张易宁[2] WANG Qiming;CHEN Zhuo;CHEN Yuanqiang;CHEN Sujing;ZHANG Yining(College of Chemistry and Materials,Fujian Normal University,Fuzhou 350007,China;Key Laboratory of Photoelectric Materials Chemistry and Physics,Fujian Institute of Material Structure,Chinese Academy of Sciences,Fuzhou 350002,China)

机构地区：[1]福建师范大学化学与材料学院,福建福州350007 [2]中国科学院福建物质结构研究所光电材料化学与物理院重点实验室,福建福州350002

出　　处：《电子元件与材料》2023年第4期395-402,共8页Electronic Components And Materials

基　　金：中科院STS区域重点项目(KFJ-STS-QYZD-2021-09-001);福建省STS计划配套项目(2021T3036,2020T3004,2019T3017,2020T3030);福建省引导性项目(2020H0040);福州市科技项目(2021-ZD-213);洁净能源研究院-榆林学院联合实验室(Grant No.2021009)。

摘　　要：铋(Bi)作为负极材料表现出比石墨更高的理论容量,引起了广泛的关注。然而,在锂化过程中,较大的体积变化和较差的循环稳定性阻碍了Bi负极的发展。为了克服上述缺点,通过电化学原位还原将钒酸铋负极转化为具有三维蜂窝结构的纳米Bi负极,并进一步研究Bi负极充放电机理及形貌变化。结果表明:纳米Bi因具有大的比表面积为锂离子嵌入提供了更多的活性位点,带来了高的比容量;同时,其三维蜂窝结构为Bi纳米颗粒在充放电过程中的体积变化提供了机械应变空间,缓解了Bi的体积膨胀,提高了电极的稳定性。研究表明,纳米Bi负极在100 mA·g^(-1)下的稳定放电比容量为497.5 mAh·g^(-1)。本研究为高能量锂离子电池负极提供了一种新的途径,使得纳米Bi有望成为锂离子电池高能负极的潜在候选者。As a material for the anodes,bismuth(Bi)exhibits higher theoretical capacity than graphite.Nevertheless,high volume variations and poor cycle stability during the lithiation process impede the development of Bi anodes.To address the aforementioned issues,the bismuth vanadate anode was changed into a nano-Bi anode with a three-dimensional honeycomb structure through electrochemical in-situ reduction.The charge-discharge process and morphological change of the Bi anode were investigated further.Finally,the electrochemical properties of the materials were characterized using galvanostatic charge/discharge(GCD).The results indicate that nano-Bi offers large specific surface area,which enables more active sites for lithium-ion intercalation and the high specific capacity.At the same time,its three-dimensional honeycomb structure creates the mechanical strain gap for the volume change of Bi nanoparticles during charge and discharge process,which reduces bismuth volume expansion and increases the electrode stability.Moreover,as the number of charge and discharge cycles increased,the shape of Bi progressively changed from three-dimensional honeycomb to dandelion-like one with thin branches.The results demonstrate that the nano-Bi anode exhibits the steady discharge capacity of 497.5 mAh·g^(-1) at 100 mA·g^(-1).The capacity retention rate is 63.9% after 200 cycles at the current density of 100 mA·g^(-1).At the same time,the coulombic efficiency remains over 100%,and the highest specific capacity throughout the cycle of the battery is 777.1 mAh·g^(-1).This provides a novel preparation method for high-energy lithium-ion battery anodes,making nano-Bi a possible contender for high-energy anodes for lithium-ion batteries.

关 键 词：钒酸铋 纳米铋 铋负极 锂离子电池 

分 类 号：TM912[电气工程—电力电子与电力传动]