【作者】 岳国强；

【导师】 陈春华；

【作者基本信息】 中国科学技术大学 ， 材料学， 2010， 硕士

【摘要】 高速发展的便携消费电子、电动汽车和智能电网储能电池市场加速了对高性能锂离子电池的需求,特别是高能量密度、高功率密度、低成本和长循环寿命的锂离子电池。开发新型锂离子电池正负极材料成为解决这些问题的主要方向之一。诸多科学家在寻找新型负极材料上做了许多努力。铁基氧化物由于比容量高、原材料丰富和成本低廉,成为其中一种重要的具有潜在应用价值的新型负极材料,受到诸多科学家的青睐。本论文内容涉及自催化反向原子转移自由基聚合制备Li-Fe复合氧化物负极材料、Li-Fe复合氧化物负极材料商业化应用开发包括性能优化和工艺优化、硫化铜(CuS)负极材料固液法制备与表征等。在论文第一章绪论中,作者简要地回顾了电池的发展历史,介绍了锂离子电池的原理与生产工艺,重点介绍了负极材料特别是过渡金属氧化物的研究现状,最后简要地提出了本论文的研究目标和方法。在第二章中,扼要地介绍本论文中主要用到的实验仪器和药品,详细介绍了实验中使用到的测试扣式电池的制备过程,以及主要的电化学和结构测试手段。在第三章中,利用自催化反向原子转移自由基聚合的方法制备出Li-Fe复合氧化物。在本课题组已经开发的丙烯酸热聚合和辐照凝胶聚合的方法以及反向原子转移自由基聚合基础上探索出自催化反向原子转移自由基聚合法制备Li-Fe复合氧化物。与热聚合和辐照凝胶聚合相比较,该合成方法不需要引发的热源和辐射源,能耗低,工艺简单、成本低。与反向原子转移自由基聚合相比较,不需要引入有毒的引发剂和催化剂,合成过程绿色。该方法为工业界大规模制备纳米Li-Fe复合氧化物提供了一种可能的途径,较其他凝胶聚合法具有很好的普适性。针对Li-Fe复合氧化物首次库伦效率低、能量效率低的问题以及工业生产中负极采用用水性胶黏剂工艺的实际情况,在第四章里采用将Li-Fe复合氧化物与石墨混合形成混合电极的方法来提高电极的首次库伦效率,并对电极配方进行了优化。经过优化,电极的首次库伦效率可达82.0%。同时还开发了Li-Fe复合氧化物与石墨混合电极的水性胶黏剂工艺,同时对电极配方进行了进一步优化,使用水性胶黏工艺的混合电极首次库伦效率可达到87.7%。在第五章中,我们采用固液法合成了六角花状结构的CuS,并对CuS的电化学性能进行了表征与分析。在最后,对本论文的创新和不足作了简要总结,并对今后可能的研究方向提出了一些建议。更多还原

【Abstract】 The rapid development of portable consumer electronics, electric vehicles and smart grid energy storage devices for solar cells and wind energy accelerates the demand of high-performance lithium ion batteries, especially for high power density, high capacity density, low cost and long cycle life. Many studies have been performed to identify alternative materials for anode. A variety of transition metal oxides have been employed for this purpose. Materials based on iron oxide have been considered as potential substitute anode materials due to their high storage capacities, their low cost, environmental friendliness and the abundance of their raw materials. It includes the synthesis of Li-Fe composite oxide anode materials using a so-called self-catalytic reverse atom transfer radical polymerization approach in this Master thesis. And the improvement and optimization of anode electrode to meet the comecial application which includes optimizating peformance and crafts. Finally, we apply a solid-liquid reaction method to prepared copper sulfide (CuS).In Chapter 1, we introduce the history and status of lithium-ion batteries, the working principle and manufacturing procedure, anode materials especially transition metal oxides, the methodology and objectives of this thesis.In Chapter 2, we list the experimental chemicals and equipments used in the thesis. And we present the process of making a 3023 type coin cell in detail. The electrochemical and structural analyses methods are also described.In Chapter 3, we explore a new gel synthesis method named“self-catalytic reverse atom transfer radical polymerization”method to prepare Li-Fe composite oxide anode materials powders. This method is based on the "Radiated Polymer Gel”method and thermal acrylic acid polymerization process in our group and the reverse atom transfer radical polymerization (RATRP). In comparison with "Radiated Polymer Gel”method and thermal acrylic acid polymerization process, our method has some advantages including: no need of thermal or radioactive source; low energy consumption and easily controllable. While compared with the usual reverse atom transfer radical polymerization (RATRP), there is no need of poisonous initiator and catalyst in this method which is therefore a really green synthesis process. It has the potential to be used to synthesize nano-sized Li-Fe composite oxide in massive production.To address the issues of low initial coulombic efficiency and low energy efficiency of Li-Fe composite oxide, in Chapter 4, we mixed the Li-Fe composite oxide and graphite as a mixed anode to enhance the initial coulombic efficiency. In the same time, we also optimized the composition of the mixed anode laminate. The initial coulombic efficiency can be increased to 82.0% after optimization. Besides this, we developed the aqueous binder process of making the mixed Li-Fe composite oxide and graphite anode electrode laminate and optimized the composition. After optimization, the initial coulombic efficiency can reach 87.7%.In Chapter 5, we used a solid-liquid reaction method to prepare hexangular flower type copper sulfide (CuS). We also tested the electrochemical properties and conducted structural analyses of this copper sulfide.At last, in Chapter 6, the author listed the achievements and the deficiency in this thesis. And some prospects and suggestions in the future research directions are presented there.更多还原