硅烷偶联剂表面处理对LiNi0.8Co0.15Al0.05O2结构和性能的影响

doi:10.15541/jim20170461

摘要/Abstract

摘要：

用硅烷偶联剂加热分解的简便方法对锂离子电池正极材料LiNi_0.8Co_0.15Al_0.05O₂(NCA)的表面进行处理, 利用XRD结合Rietveld精修、SEM、TEM、DSC、EIS和恒流充放电等方法对材料进行表征。结果显示, 硅烷偶联剂经450℃加热分解后得到的非晶态SiO₂均匀包覆在材料表面, 包覆不改变 NCA的晶体结构, 但明显改善了材料性能。在60℃环境中, 0.2C、1C下包覆材料(简写为a-NCA)的放电比容量分别为176.4、158.9 mAh·g^-1, 高于NCA的174.2、153.8 mAh·g^-1; 50周循环后a-NCA的容量保持率为91.4 %, 远高于NCA的86.5 %; 同时, 经包覆后材料的热稳定性大幅度提高。其原因是包覆层抑制了NCA在循环过程中与电解液发生副反应, 有效降低了离子迁移的界面膜电阻, 并抑制了晶体结构变化。

关键词: LiNi_0.8Co_0.15Al_0.05O₂, 硅烷偶联剂, 包覆, 电化学性能, 热稳定性

Abstract:

Silane coupling agent was used to treat surface of cathode material LiNi_0.8Co_0.15Al_0.05O₂ (NCA) for lithium ion battery by a simple thermal decomposition method. Structures and properties of the materials were characterized by XRD combined with Rietveld refinement, SEM, TEM, DSC, EIS and galvanostatic charge/discharge test. The results show that amorphous SiO₂ obtained by decomposition of silane coupling agent is uniformly coated on the surface of NCA whose crystal structure remain unaffected while its comprehensive properties are significantly improved especially at high temperature. In the environment of 60℃ at 0.2C and 1C rate , the discharge capacities of the coated NCA (a-NCA) are 176.4 mAh·g^-1 and 158.9 mAh·g^-1 respectively, whereas counterparts of the pristine NCA are slightly lower and reduced to 174.2 mAh·g^-1and 153.8 mAh·g^-1, respectively. The capacity retention of a-NCA is 91.4% while that of NCA is 86.5% after 50 charge/discharge cycles. Moreover, thermal stability of a-NCA is greatly improved compared with the uncoated material under test condition of 60℃ in that the coating inhibits the side reaction between NCA surface and electrolyte which successfully restrains the surface film resistance and restricts variation of the crystal structure of material in process of cycling.

Key words: LiNi_0.8Co_0.15Al_0.05O₂, silane coupling agent, coating, electrochemical performance, thermal stability

中图分类号:

TQ152

范广新, 刘泽萍, 闻寅, 刘宝忠. 硅烷偶联剂表面处理对LiNi_0.8Co_0.15Al_0.05O₂结构和性能的影响[J]. 无机材料学报, 2018, 33(7): 749-755.

FAN Guang-Xin, LIU Ze-Ping, WEN Yin, LIU Bao-Zhong. Surface Treatment on Structure and Property of LiNi_0.8Co_0.15Al_0.05O₂ by Silane Coupling Agent[J]. Journal of Inorganic Materials, 2018, 33(7): 749-755.

图/表 15

图1 硅烷偶联剂KH550在空气气氛中的TG-DTA曲线(a)及在450℃保温5 h热分解产物的XRD图谱(b)

Fig. 1 (a) TG-DTA curves of the KH550 silane coupling agent in air and (b) XRD pattern for thermal decomposition product of the silane coupling agent after heating at 450℃ for 5 h

图2 NCA和a-NCA的XRD图谱(a)及局部放大图谱(b)

Fig. 2 (a) XRD patterns for NCA and a-NCA, and (b) their enlarged XRD patterns.

图3 a-NCA的XRD Rietveld结构精修图

Fig. 3 XRD Rietveld refinement of a-NCA

表1 NCA和a-NCA的结构参数

Table 1 Structural parameters of NCA and a-NCA

Sample	a/nm	c/nm	c/a	FWHM/(°)
Sample	a/nm	c/nm	c/a	(003)	(104)
NCA	0.2869	1.4193	4.948	0.130	0.225
a-NCA	0.2869	1.4200	4.949	0.131	0.228

图4 NCA(a)~(b)和a-NCA (c)~(d)的SEM照片

Fig. 4 SEM images of NCA(a, b) and a-NCA (c, d)

图5 a-NCA的EDS能谱图

Fig. 5 EDS mapping of a-NCA

图6 a-NCA的TEM照片

Fig. 6 TEM image of a-NCA

图7 NCA和a-NCA的首次充放电曲线 (a)及对应的微分容量曲线(b)

Fig. 7 (a) Initial charge-discharge curves and (b) the corresponding differential capacity (dQ/dV) of NCA and a-NCA

表2 NCA和a-NCA的电化学性能

Table 2 Electrochemical performances of NCA and a-NCA

Sample	0.1C/(mAh·g^-1)	0.2C/(mAh·g^-1)	1C/(mAh·g^-1)	Difference values of (Ni²⁺/Ni⁴⁺)/V	Capacity retention
NCA-RT	171.5	164.7	146.0	0.11	94.7%
a-NCA-RT	164.6	153.8	140.2	0.10	96.0%
NCA-HT	184.9	174.2	153.8	0.05	86.5%
a-NCA-HT	183.2	176.4	158.9	0.01	91.4%

图8 NCA和a-NCA的倍率和循环性能

Fig. 8 Rate capacity and cyclic ability of NCA and a-NCA

图9 NCA和a-NCA在(a)室温和(b)高温的交流阻抗图, (b)中的插图为等效电路

Fig. 9 EIS plots of NCA and a-NCA at (a) room temperature and (b) high temperature with inset in (b) showing the corresponding equivalent circuit diagram

表3 NCA和a-NCA循环前后的交流阻抗值

Table 3 Electrochemical AC impedance values of NCA and a-NCA

Sample	Condition	R_s/Ω	R_f/Ω	R_ct/Ω	W_o/(×10^-3, Ω)
NCA	Original	8.6	136.4	211.9	2.0
	RT-50th	7.5	8.3	126.1	2.8
	HT-50th	7.9	55.7	114.2	7.5
a-NCA	Original	6.5	106.0	156.6	3.1
	RT-50th	4.5	7.4	92.1	4.9
	HT-50th	6.2	21.4	75.5	8.6

图10 NCA和a-NCA的DSC曲线

Fig. 10 DSC curves of NCA and a-NCA

图11 NCA和a-NCA在室温(a)和高温(b)循环前后(003)峰的XRD图谱

Fig. 11 XRD patterns of (003) peak in original and the 50th cycle sample for NCA and a-NCA at room temperature (a) and high temperature (b)

表4 NCA和a-NCA室温和高温循环前后的结构参数

Table 4 Structural parameters of NCA and a-NCA before and after cycling at room temperature and high temperature

	Condition	a/nm	Δa/a	c/nm	V/(×10^-3, nm³)
NCA	Original	0.2869		1.4193	0.1011
	RT-50th	0.2858	0.39%	1.4246	0.1007
	HT-50th	0.2841	0.96%	1.4299	0.995
a-NCA	Original	0.2869		1.4199	0.1012
	RT-50th	0.2862	0.26%	1.4224	0.1008
	HT-50th	0.2857	0.43%	1.4242	0.1001

参考文献 23

[1]	NITTA N, WU F, LEE J T,et al.Li-ion battery materials: present and future. Mater. Today, 2015, 18(5): 252-264.
[2]	TRAN H Y, TÄUBERT C, WOHLFAHRT-MEHRENS M. Influence of the technical process parameters on structural mechanical and electrochemical properties of LiNi0.8Co0.15Al0.05O2 based electrodes - a review.Prog. Solid State Ch., 2014, 42(4): 118-127.
[3]	WANG H, LAI C, XIAO Y,et al.A new lithium-ion battery with LiNi0.8Co0.15Al0.05O2 cathode and lithium pre-doping hard carbon anode.Mater. Lett., 2015, 160: 250-254.
[4]	ZUO D, TIAN G, LI X,et al.Recent progress in surface coating of cathode materials for lithium ion secondary batteries.J. Alloys Comp., 2017, 706: 24-40.
[5]	XU Y, LI X, WANG Z,et al.Structure and electrochemical performance of TiO2-coated LiNi0.8Co0.15Al0.05O2 cathode materials.Mater. Lett., 2015, 143: 151-154.
[6]	LIU W, HU G, DU K,et al.Surface coating of LiNi0.8Co0.15Al0.05O2 with LiCoO2 by a molten salt method.Surf. Coat. Tech., 2013, 216: 267-272.
[7]	HUANG B, LI X, WANG Z,et al.A facile process for coating amorphous FePO4 onto LiNi0.8Co0.15Al0.05O2 and the effects on its electrochemical properties.Mater. Lett., 2014, 131: 210-213.
[8]	LEE D J, SCROSATI B, SUN Y K.Ni3(PO4)2-coated LiNi0.8Co0.15Al0.05O2 lithium battery electrode with improved cycling performance at 55℃.J. Power Sources, 2011, 196(18): 7742-7746.
[9]	HE X, DU C, SHEN B,et al.Electronically conductive Sb-doped SnO2 nanoparticles coated LiNi0.8Co0.15Al0.05O2 cathode material with enhanced electrochemical properties for Li-ion batteries.Electrochim. Acta, 2017, 236: 273-279.
[10]	CHEN C, TAO T, WANG Q,et al.High-performance lithium ion batteries using SiO2-coated LiNi0.5Co0.2Mn0.3O2 microspheres as cathodes.J. Alloys Comp., 2017, 709: 708-716.
[11]	FAN Y, WANG J, TANG Z,et al.Effects of the nanostructured SiO2 coating on the performance of LiNi0.5Mn1.5O4 cathode materials for high voltage Li-ion batteries.Electrochim. Acta, 2007, 52(11): 3870-3875.
[12]	LIANG L, HU G, JIANG F,et al.Electrochemical behaviours of SiO2-coated LiNi0.8Co0.1Mn0.1O2 cathode materials by a novel modification method.J. Alloys Comp., 2016, 657: 570-581.
[13]	ZHOU P, ZHANG Z, MENG H,et al.SiO2-coated LiNi0.915Co0.075Al0.01O2 cathode material for rechargeable Li-ion batteries.Nanoscale, 2016, 8(46): 19263-19269.
[14]	CHO W, KIM S M, SONG J H,et al.Improved electrochemical and thermal properties of nickel rich LiNi0.6Co0.2Mn0.2O2 cathode materials by SiO2 coating.J. Power Sources, 2015, 282: 45-50.
[15]	LI Y, ZHAO S.Electrochemical performance of SiO2-coated LiFePO4 cathode materials for lithium ion battery.J. Alloys Comp., 2011, 509(3): 957-960.
[16]	MALLAKPOUR S, MADANI M.A review of current coupling agents for modification of metal oxide nanoparticles.Prog. Org. Coat., 2015, 86: 194-207.
[17]	LIU HUAN-MIN, HUANG KE-LONG, XUE JIAN-JUN,et al.Study on the performance of LiCrxMn2-xO4 by surface treatment with silane coupling agent.Battery Bimonthly, 2004, 34(6): 403-405.
[18]	王雪明. 硅烷偶联剂在金属预处理及有机涂层中的应用研究. 济南:山东大学硕士学位论文, 2005.
[19]	HUANG WEI, CAO XUE-JUAN, ZHU HONG-ZHOU,et al.Research on physic adsorption and photocatalytic activity of TiO2/SiO2 with different molar content of SiO2.J. Wuhan Univ. Technol., 2015, 37(9): 25-31.
[20]	CHO Y, CHO J.Significant improvement of LiNi0.8Co0.15Al0.05O2 cathodes at 60℃ by SiO2 dry coating for Li-ion batteries.J. Electrochem. Soc., 2010, 157(6): A625-A629.
[21]	SHI Y, ZHANG M, QIAN D,et al.Ultrathin Al2O3 coatings for improved cycling performance and thermal stability of LiNi0.5Co0.2Mn0.3O2 cathode material.Electrochim. Acta, 2016, 203: 154-161.
[22]	YIN S C, RHO Y H, SWAINSON I,et al.X-ray/neutron diffraction and electrochemical studies of lithium de/re-intercalation in Li1-xCo1/3Ni1/3Mn1/3O2 (x=0→1).Chem. Mater., 2006, 18(7): 1901-1910.
[23]	LIN C K, REN Y, AMINE K,et al.In situ high-energy X-ray diffraction to study overcharge abuse of 18650-size lithium-ion battery.J. Power Sources, 2013, 230: 32-37.

硅烷偶联剂表面处理对LiNi_0.8Co_0.15Al_0.05O₂结构和性能的影响

Surface Treatment on Structure and Property of LiNi_0.8Co_0.15Al_0.05O₂ by Silane Coupling Agent

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