CAJ | 학술논문

以氧化淀粉为碳前驱体和分散剂,采用冷冻干燥法制备LiFePO_4/C正极材料,利用XRD、SEM、恒流充放电等手段对LiFePO_4/C复合正极材料的物相结构、表观形貌及材料的电化学性畿进行研究.结果表明:冷冻干燥法可以使原料变成粉末,同时不破坏其均匀的混合状态;以氧化淀粉为碳源,碳含量为7.07%,在700℃高温下煅烧12 h合成的材料具有完整的晶型结构,颗粒大小均一,首次放电比容量达到165 mAh/g,接近理论放电比容量.1 C倍率下,50次循环后的容量衰减仅为0.20%,5 C倍率下,50次循环后的容量衰减为1.39%,电化学性能优异.
이양화정분위탄전구체화분산제,채용냉동간조법제비LiFePO_4/C정겁재료,이용XRD、SEM、항류충방전등수단대LiFePO_4/C복합정겁재료적물상결구、표관형모급재료적전화학성기진행연구.결과표명:냉동간조법가이사원료변성분말,동시불파배기균균적혼합상태;이양화정분위탄원,탄함량위7.07%,재700℃고온하단소12 h합성적재료구유완정적정형결구,과립대소균일,수차방전비용량체도165 mAh/g,접근이론방전비용량.1 C배솔하,50차순배후적용량쇠감부위0.20%,5 C배솔하,50차순배후적용량쇠감위1.39%,전화학성능우이.
The LiFePO_4/C cathode materials was prepared by freeze drying method using oxidized starch as carbon source and dispersant. The structure, apparent morphology, electronic conductivity were characterized by means of XRD, SEM, electrochemical techniques. The optimized process conditions were: oxidized starch as carbon source, carbon content of 7.07%, calcinations temperature is 700 ℃, calcinations time is 12 h. The sample which was synthesized by the optimized technology conditions has a complete crystal structure, size of the particle uniformity, the first discharge capacity was 165 mAh/g, close to the theoretical discharge capacity. After 50 cycles at 1 C rate, the capacity fade is only 0.20%, and 50 cycles at 5 C rate.the capacity fade is only 1.39%.It shows excellent electrochemical performance.