High-performance Low-cost Green Lithium Ion Battery Anode Materials Preparation Technology Research

Lithium-ion battery is a new type of secondary batteries developed during1990’s. Cathode material is the most important part in Lithium-ion battery. It greatly effects the performance and price of Lithium-ion battery, so it is the key to prepare the cathode material with high performance and low price in an easy method. Compared with conventional cathode materials for Lithium-ion batteries, the layered Li-rich material has many merits, such as higher capacity, lower toxicity, lower cost, and so on.In this study, Li[Lio.2oNio.133Co0.133Mn0.534]O2with good performance was prepared in an easy method, and investigated the effect of co-precipitation and solid phase method on the materials’morphology and electrochemical performance. Surface modification with AI2O3was conducted to improve the cycling stability. In the solid phase method, different metal salts were used as raw material to study the effect on material structure, specific capacity and cycling performance. Yttrium was doped to substitute cobalt, thereby reducing the cost of materials and the impact on the environment. At the same time, the wastewater generated by co-precipitation method was analyzed, and we reduced the heavy metal ions in the wastewater through changing the ratio of the reactants, excluding the possibility of causing environmental pollution.The spherical Li[Li0.20Ni0.133Co0.133Mn0.534]O2agglomerations with about10μm were synthesized by co-precipitation method, and had typical layered structure. Its initial discharge capacity was256.3mAh/g, after Al2O3coating, its discharge capacity was245.0mAh/g after80cycles with the capacity retention of95.6%. The materials prepared by solid phase method were slightly inferior to the co-precipitation method in the morphology and electrochemical performance, and subjected to different metal salts of raw materials impact. But solid phase method has simple equipment requirements, and does not generate waste, so more suitable for application in the industrialization.Doping Yttrium to substitute Cobalt had a great degree of improvement in the capacity, and doping Yttrium in the co-precipitation process was better than other methods because it helped Yttrium form lattice with other elements. But with the increasing of Yttrium doping amount, it did not always increase the positive effect of the material. Doped with2%-10%, materials had higher discharge capacity and better cycling performance. So, materials doped Yttrium could prepared as a high capacity material, and had a great rate performance in high current.In this paper, synthesis method was easier than other methods reported in the literature. It did not add ammonia as morphology control agent, not need to monitor the pH value, and could prepare materials with good structure and electrochemical properties. What’s more, we also improved the experimental method to reduce the heavy metal ion contents in the wastewater, thereby reducing environmental pollution and the loss of raw materials. From the point of industrial production, it cut down the waste of raw materials and the subsequent water treatment costs, and provided a reference for this series of cathode materials in large-scale industrial production.