Dynamic Volumography of Cylindrical Li-Ion Battery Cells by Watching Its Breath During Cycling  

作　　者：Wenxuan Jiang Haoran Li Sicong Wang Sa Wang Wei Wang 

机构地区：[1]State Key Laboratory of Analytical Chemistry for Life Science,School of Chemistry and Chemical Engineering,Nanjing University,Nanjing 210023

出　　处：《CCS Chemistry》2023年第6期1308-1317,共10页中国化学会会刊（英文）

基　　金：We thank the National Natural Science Foundation of China(W.W.,grant no.21925403,W.W.,grant no.21874070);the Excellent Research Program of Nanjing University(W.W.,grant no.ZYJH004)for their financial support.

摘　　要：It has been well-documented that the charging of Li-ion battery(LIB)is accompanied by volume expansion,a significant source of their capacity fading and structural failure.However,existing operando techniques for measuring battery expansion either use single-point detection to report the local deformation or are not sensitive enough for hard-pack cylindrical batteries.Here,we propose an optical volumography(OVG)technology,including both apparatus and methodology,to measure the absolute volume of a commercial 18650 cylindrical LIB cell by taking a series of optical images of a rotating battery and reconstructing its 3D surface profile.Charging(discharging)induced volume expansion(shrinkage),i.e.,the“breath,”of multiple battery cells can be quantitatively determined in parallel and in real time.This method has a sensitivity of up to 1×10^(−5)(ΔV/V0)and an accuracy of 0.1μm.In contrast to the overall expansion of a soft-pack pouch battery,hard-pack cylindrical cells exhibit rather small and heterogeneous wrinkle-type deformation during charging,underscoring the value of the sensitivity and spatial resolution of OVG.In addition to mapping the strain distribution,OVG further allows for differentiating the thermal-induced expansion from the reaction-induced expansion and evaluation of the state-of-charge and the state-of-health optically,with promising implications for process optimization,quality control,and energy and thermal management of batteries.

关 键 词：lithium-ion battery optical imaging in operando three-dimensional reconstruction high throughput 

分 类 号：TM912[电气工程—电力电子与电力传动]