摘要:通过喷雾干燥法制备大小可控、粒径均匀的球形NCA前体粉末。然后将前体粉末在不同压力(0,2,4,6MPa)压制成片状并放入通有氧气的管式电阻炉中煅烧12h,得到目标正极材料。XRD图谱观察到压制处理后的样品的I(003)/I(104)的衍射强度比明显增加,产生的原因可能是加压处理减少了锂层中锂和镍离子的混排。后续研究进一步证实了经过压制处理后锂层中的锂镍混排程度降低,减小了锂离子扩散时受到的阻力。电化学测试表明,这些经过压制处理后的样品比容量、循环稳定性、倍率性能等有明显的改善。EIS测试证明了锂离子的扩散系数得到了增强,样品S4的扩散系数明显高于其他三组样品,几乎是未处理样品S0的三倍。72166
毕业论文关键词:NCA;新能源;纳米球磨;喷雾干燥;压片处理;扩散系数
Synthesis and Electrochemical Properties of Nano-sized NCA
Abstract:A spherical NCA precursor powder with uniform size and uniform particle size was prepared by spray drying method。 The precursor powder was then calcined at different pressures (0,2,4,6 MPa) into flakes and placed in a tubular resistance furnace with oxygen for 12h to obtain the target cathode material。 The diffraction intensity ratio of I(003) / I(104) of the sample after pressing was observed by XRD pattern。 The reason for this might be that the pressure treatment reduced the mixing of lithium and nickel ions in the lithium layer。 Subsequent studies have further confirmed that the degree of lithium-nickel mixing in the lithium layer after reduction has been reduced, reducing the resistance to lithium ion diffusion。 Electrochemical tests show that these samples have been significantly improved in their specific capacity, cycle stability, and magnification properties。 The EIS test showed that the diffusion coefficient of the lithium ion was enhanced and the diffusion coefficient of the sample S4 was significantly higher than that of the other three groups, almost three times the untreated sample S0。
KeyWords: NCA; New Energy; Nano-milling; Spray Drying; Tablet Treatment; Diffusion Coefficient
目 录
1 绪论 1
1。1引言 1
1。2锂离子电池简介 1
1。2。1锂离子电池发展状况 1
1。2。2锂离子电池的工作原理 2
1。2。3锂离子电池正极材料 3
1。3 NCA三元正极材料的研究进展 3
1。3。1 三元材料NCM正极材料 3
1。3。2 三元材料NCA正极材料 4
1。4 常用的NCA的合成方法 4
1。4。1 溶胶-凝胶法 4
1。4。2 固相合成法 4
1。4。3 喷雾干燥法 5
1。5 课题的主要内容 5
1。5。1 课题研究的目的与意义 5
1。5。2 课题研究内容 5
1。5。3 实验方案设计 6
2 实验及表征 7
2。1 实验原料 7
2。2 实验仪器 7
2。3 材料制备 8
2。4 电极材料制备与电池组装 9
2。5 物理性能表征