锂电池正极材料NCA的制备及研究
本文还尝试了使用一步水热法合成NCA，设计了三种方案，结果都不理想。对三种方案结果进行分析，得出了2个结论：第一，在一步水热法过程中，氧化剂的量对一步水热法的影响不大；第二，在一步水热法过程中，200℃的水热温度优于120℃。
关键词 NCA正极材料 溶胶凝胶法 水热-溶胶凝胶法 一步水热法 电化学性能
毕业论文设计说明书外文摘要
Title Synthesis and Properties Research of NCA Cathode Materials for Lithium-ion Batteries
Abstract
In this paper, sol-gel method and hydrothermal-sol-gel method was used to prepare NCA cathode materials, the prepared materials was characterized by XRD and SEM and their electrochemical performance is evaluated, discharge capacity of NCA cathode materials prepared by the two methods was 165mAh/g and 175mAh/g respectively, and both with a good cycleability. The effects of the addition of citric acid and sintering temperature on the electrochemical properties of obtained NCA materials during preparing NCA materials by a sol-gel method was studied, observed that too much or too little complexing agent citric acid is not good to obtain high performance NCA materials and too high sintering temperature is not good to obtain pure phase of NCA.
In this paper, a single-step hydrothermal method was tried to prepare NCA, three different ways were designed and no one achieved the aim. The results of the three ways were analyzed and got two conclusions: firstly, the amount of oxidant have little effect on the process of single-step hydrothermal method; secondly, temperature 200℃ is better than 120℃ during hydrothermal process.
Keywords NCA cathode materials sol-gel method hydrothermal-sol-gel method
single-step hydrothermal method electrochemical performance
目 次
1 引言 1
1.1 锂离子电池的发展历史、现状及前景 1
1.2 锂离子电池的工作原理及特点 2
1.3 锂离子电池正极材料 3
1.3.1 钴酸锂 3
1.3.2 锰酸锂 3
1.3.3 磷酸亚铁锂 4
1.3.4 NCA正极材料 4
1.4 NCA正极材料的合成 4
1.4.1 高温固相法 4
1.4.2 共沉淀法 5
1.4.3 溶胶凝胶法 5
1.4.4 喷雾热分解法 6
1.5 NCA正极材料的表面改性 6
1.6 本文的研究目的和主要内容 6
2 实验 8
2.1 实验材料和实验仪器 8
2.1.1 实验材料 8
2.1.2 实验仪器 8
2.2 溶胶凝胶法制NCA 9
2.2.1 实验主要流程 10
2.2.2 具体实验方法 10
2.3 水热-溶胶凝胶法制NCA 11
2.3.1 实验主要流程 11
2.3.2 前驱体的合成 12
2.3.3 NCA材料的制备 13