Analysis of stable coating window of lithium battery electrode paste based on phase field models

doi:10.19799/j.cnki.2095-4239.2023.0300

Abstract

Abstract:

Electrode coating is one of the key processes in the manufacturing of lithium-ion battery electrodes. The coating quality determines the uniformity of the electrode structure, which in turn affects the performance and lifespan of the battery. In response to the quality control problem of electrode slurry slot die coating, this study selects a local area composed of the slot die and the fluid collector as the research object and establishes a multiphysics field model coupled with phase field and flow field. Based on this model, the slurry flow during the slit coating process was analyzed through numerical simulation, providing a reference for optimizing the coating process parameters of lithium battery electrode slurry. Similarly, a stable coating window was determined based on the coating quality. The reliability of the simulation model was verified by comparing it with experimental results. We optimized the main dimensions of the coating die with the goal of expanding the coating window and achieving high-speed and stable coating. The results indicated that excessive or insufficient slurry flow rate will cause bubbles to mix in or overflow upstream, making the coating process unstable. The main geometric dimensions of the slot die had a specific impact on the stable coating window; however, simply increasing or decreasing the geometric dimensions cannot broaden the coating window. Asymmetric adjustment of the upstream and downstream die heads could increase the upper limit of slurry flow by 40% by changing the relative magnitude of upstream and downstream flow resistance.

Key words: lithium ion battery, manufacturing process, electrode slurry, slot die coating, numerical simulation

CLC Number:

TQ 024.1

Yuxin CHEN, Jiamu YANG, Cheng LIAN, Honglai LIU. Analysis of stable coating window of lithium battery electrode paste based on phase field models[J]. Energy Storage Science and Technology, 2023, 12(7): 2185-2193.

Figures/Tables 12

Fig. 1

Table 1

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Fig. 6

Table 2

Fig. 7

Fig. 8

Table 3

Fig. 9

References 21

1	吴敬华, 杨菁, 刘高瞻, 等. 固态锂电池十年(2011—2021)回顾与展望[J]. 储能科学与技术, 2022, 11(9): 2713-2745.
	WU J H, YANG J, LIU G Z, et al. Review and prospective of solid-state lithium batteries in the past decade(2011—2021)[J]. Energy Storage Science and Technology, 2022, 11(9): 2713-2745.
2	李文俊, 徐航宇, 杨琪, 等. 高能量密度锂电池开发策略[J]. 储能科学与技术, 2020, 9(2): 448-478.
	LI W J, XU H Y, YANG Q, et al. Development of strategies for high-energy-density lithium batteries[J]. Energy Storage Science and Technology, 2020, 9(2): 448-478.
3	缪平, 姚祯, JOHN Lemmon, 等. 电池储能技术研究进展及展望[J]. 储能科学与技术, 2020, 9(3): 670-678.
	MIAO P, YAO Z, JOHN L, et al. Current situations and prospects of energy storage batteries[J]. Energy Storage Science and Technology, 2020, 9(3): 670-678.
4	ZHANG X Q, ZHAO C Z, HUANG J Q, et al. Recent advances in energy chemical engineering of next-generation lithium batteries[J]. Engineering, 2018, 4(6): 831-847.
5	郭德超, 郭义敏, 张啟文, 等. 锂离子电池用无溶剂干法电极的制备及其性能研究[J]. 储能科学与技术, 2021, 10(4): 1311-1316.
	GUO D C, GUO Y M, ZHANG Q W, et al. Preparation and characterization of solvent-free dry electrodes for lithium ion batteries[J]. Energy Storage Science and Technology, 2021, 10(4): 1311-1316.
6	梁卫华, 吴大勇, 舒均国. 逗号刮刀涂布流场理论分析与数值模拟[J]. 储能科学与技术, 2021, 10(2): 565-576.
	LIANG W H, WU D Y, SHU J G. Theoretical analysis and numerical simulation of flow field in comma scraper coating[J]. Energy Storage Science and Technology, 2021, 10(2): 565-576.
7	RYU M, HONG Y K, LEE S Y, et al. Ultrahigh loading dry-process for solvent-free lithium-ion battery electrode fabrication[J]. Nature Communications, 2023, 14: 1316.
8	CHENG P, LIN Y Z, ZAWACKA N K, et al. Comparison of additive amount used in spin-coated and roll-coated organic solar cells[J]. Journal of Materials Chemistry A, 2014, 2(45): 19542-19549.
9	SPIEGEL S, HOFFMANN A, KLEMENS J, et al. Optimization of edge quality in the slot-die coating process of high-capacity lithium-ion battery electrodes[J]. Energy Technology, 2023, 11(5): doi: 10.1002/ente.202200684.
10	闫晓清, 胡志宇, 刘凤泉, 等. 锂离子电池内隔膜褶皱的原因及消除[J]. 储能科学与技术, 2021, 10(1): 156-162.
	YAN X Q, HU Z Y, LIU F Q, et al. Causes and elimination of internal diaphragm wrinkles in lithium ion batteries[J]. Energy Storage Science and Technology, 2021, 10(1): 156-162.
11	谭鹏辉. 锂离子电池极片高效挤压涂布数值模拟及工艺基础[D]. 武汉: 华中科技大学, 2022.
	TAN P H. Numerical simulation and technological basis of efficient extrusion coating of lithium ion battery pole pieces[D]. Wuhan: Huazhong University of Science and Technology, 2022.
12	林黎明. 动力锂电池浆料狭缝式挤压涂布流场数值模拟研究[D]. 郑州: 郑州大学, 2021.
	LIN L M. Numerical simulation of flow field in slit extrusion coating of power lithium battery slurry[D]. Zhengzhou: Zhengzhou University, 2021.
13	AKBARZADEH V, HRYMAK A N. Coupled fluid-particle modeling of a slot die coating system[J]. AIChE Journal, 2016, 62(6): 1933-1939.
14	杜江龙, 林伊婷, 杨雯棋, 等. 模拟仿真在锂离子电池热安全设计中的应用[J]. 储能科学与技术, 2022, 11(3): 866-877.
	DU J L, LIN Y T, YANG W Q, et al. Application of simulation in thermal safety design of lithium-ion batteries[J]. Energy Storage Science and Technology, 2022, 11(3): 866-877.
15	DU J L, TAO H L, CHEN Y X, et al. Thermal management of air-cooling lithium-ion battery pack[J]. Chinese Physics Letters, 2021, 38(11): 122-135.
16	HUANG T L, TAN P H, ZHONG Z Y, et al. Numerical and experimental investigation on the defect formation in lithium-ion-battery electrode-slot coating[J]. Chemical Engineering Science, 2022, 258: doi: 10.1016/j.ces.2022.117744.
17	TAN P H, DIAO S M, HUANG T L, et al. Numerical and experimental study on coating uniformity control in simultaneous double-sided slot coating with a novel contacted slot die[J]. Chemical Engineering Science, 2020, 222: doi: 10. 1016/j. ces. 2020. 115716.
18	AHN W G, LEE S H, NAM J, et al. Effect of upstream meniscus shape on dynamic wetting and operating limits of Newtonian coating liquids in slot coating bead flows[J]. Journal of Coatings Technology and Research, 2018, 15(5): 1067-1076.
19	BHAMIDIPATI K L, DIDARI S, BEDELL P, et al. Wetting phenomena during processing of high-viscosity shear-thinning fluid[J]. Journal of Non-Newtonian Fluid Mechanics, 2011, 166(12/13): 723-733.
20	PAN W T, CHEN Z K, CHEN X L, et al. Slot die coating window for a uniform fuel cell ink dispersion[J]. AIChE Journal, 2022, 68(8): e17719.
21	MALAKHOV R, TJIPTOWIDJOJO K, SCHUNK P R. Mechanics of the low-flow limit in slot-die coating with no vacuum[J]. AIChE Journal, 2019, 65(6): e16593.

参数	数值
狭缝宽度W/mm	0.3，0.5，0.7
模唇宽度L/mm	0.8，1.0，1.5
模头高度H/mm	0.15，0.2，0.3
模头倾角 β /(°)	45
浆料密度 ρ_l/(kg/m³)	1320
浆料表面张力 σ /(N/m)	0.066
浆料黏度 μ_l/(Pa∙s)	式(1)
参考剪切速率 γ_ref/s^-1	1
流体一致性系数M/(Pa∙s)	3.585
流动特性指数N	0.6322
浆料-模头接触角 θ₁/(°)	72.5
浆料-集流体接触角 θ₂/(°)	55.6
空气密度 ρ_g/(kg/m³)	1.2
空气黏度 μ_g/(mPa∙s)	0.02

分组	调整的模头尺寸	数值
H1-1	模头高度H/mm	0.3
H1-2	模头高度H/mm	0.15
W1-1	狭缝宽度W/mm	0.7
W1-2	狭缝宽度W/mm	0.3
L1-1	模唇宽度L/mm	1.5
L1-2	模唇宽度L/mm	0.8

分组	调整的模头尺寸	数值
L2-1	上游模唇宽度L_u/mm	1.5
L2-1	下游模唇宽度L_d/mm	0.8
L2-2	上游模唇宽度L_u/mm	0.8
L2-2	下游模唇宽度L_d/mm	1.5
H2-1	上游模头高度H_u/mm	0.3
H2-1	下游模头高度H_d/mm	0.15
H2-2	上游模头高度H_u/mm	0.15
H2-2	下游模头高度H_d/mm	0.3

[1]	Zenghui HAO, Xunliang LIU, Yuan MENG, Nan MENG, Zhi WEN. Effect of electrode interface microstructure on the performance of solid-state lithium-ion battery [J]. Energy Storage Science and Technology, 2023, 12(7): 2095-2104.
[2]	Yikun WU, Jie HE, Le YANG, Weili SONG, Haosen CHEN. Multiscale and multiphysics theoretical model and computational method for lithium-ion batteries [J]. Energy Storage Science and Technology, 2023, 12(7): 2141-2154.
[3]	Yuxin CHEN, Jiamu YANG, Dongbo LI, Cheng LIAN, Honglai LIU. Numerical simulation of the vacuum drying process of cylindrical lithium-ion batteries [J]. Energy Storage Science and Technology, 2023, 12(6): 1957-1967.
[4]	Zian PENG, Wenchao DUAN, Jie LI, Xiaoqin SUN, Mengjie SONG. Energy storage characteristics of a shell-and-tube phase change energy storage heat exchanger for data centers [J]. Energy Storage Science and Technology, 2023, 12(6): 1765-1773.
[5]	Yongshuai YU, Yongfeng LIU, Pucheng PEI, Lu ZHANG, Shengzhuo YAO. Effect of cathode relative humidity on membrane water content and performance of PEMFC [J]. Energy Storage Science and Technology, 2023, 12(6): 1755-1764.
[6]	Xinyu LI, Xuebing HAN, Languang LU, Jianqiu LI, Minggao OUYANG. Optimization of an impedance model for power Li-ion batteries based on a large multiplier current pulse [J]. Energy Storage Science and Technology, 2023, 12(5): 1686-1694.
[7]	Jialiang LIU, Cuijing GUO, Huanling WANG. Safety detection and verification of energy storage in lithium-ion battery based on fire fault tree model [J]. Energy Storage Science and Technology, 2023, 12(5): 1695-1704.
[8]	Liyu ZHAO, Huanwu SUN, Shichuang LIU, Zhiyuan YAN. Energy consumption comparison and optimization of auxiliary power-battery heating system of heavy truck [J]. Energy Storage Science and Technology, 2023, 12(4): 1139-1147.
[9]	Minyuan GUAN, Jianliang SHEN, Guohua XU, Shun TANG, Weixin ZHANG, Yuancheng CAO. Design and performance research of targeted-fire fighting equipment for lithium-ion battery energy storage system [J]. Energy Storage Science and Technology, 2023, 12(4): 1131-1138.
[10]	Zifeng HU, Yaozu XU, Zhenyun DUAN, Xiangdong SHANG, Jingjiu XU. Analysis of the heat storage process of a new heat storage body structure [J]. Energy Storage Science and Technology, 2023, 12(1): 165-171.
[11]	Sujin GE, Long ZHANG, Xiaohua YANG, Wenhao SHAN, Guangqiang XU. Simulation study on the influence of air supply method on the cooling effect of energy storage battery cluster [J]. Energy Storage Science and Technology, 2023, 12(1): 150-154.
[12]	Han ZHENG, Peipei LAI, Xiaohua TIAN, Zhuo SUN, Zhejuan ZHANG. Performance of large-scale silicon particles coated with multistage carbon as anode materials for lithium-ion batteries [J]. Energy Storage Science and Technology, 2023, 12(1): 23-34.
[13]	Ao TANG, Chuanwei YAN. Modelling and simulation of flow batteries： Recent progress and prospects [J]. Energy Storage Science and Technology, 2022, 11(9): 2866-2878.
[14]	Rongyang WEI, Tian MAO, Han GAO, Jianren PENG, Jian YANG. Health state estimation of lithium ion battery based on TWP-SVR [J]. Energy Storage Science and Technology, 2022, 11(8): 2585-2599.
[15]	Hang YU, Ying ZHANG, Chaohang XU, Sihan YU. Research progress of thermal runaway prevention and control technology for lithium battery energy storage systems [J]. Energy Storage Science and Technology, 2022, 11(8): 2653-2663.