摘要
以Li2CO3和V2O5为原料,进行了固相法制备锂离子电池正极材料Li1+xV3O8的实验研究.通过TG-DTA,XRD及交流阻抗等测试方法考察了合成条件对Li1+xV3O8样品结构、电导率及电化学性能的影响.XRD结果表明:随着焙烧温度的提高,产物的(100)衍射峰相对强度增强,这使Li+在LiV3O8中嵌入脱出的路径较长.交流阻抗测试表明:随着烧结温度的提高,电导率增大,而随着烧结时间的延长,电导率出现先增大而后又减小的趋势.电化学测试结果表明,580℃焙烧20 h合成的产物具有优良的电化学性能,放电比容量最高达到254.0 mAh.g-1,10次循环后仍保持在245.6 mAh.g-1,优于高温熔融法制备的材料,是较为理想的锂离子电池候选正极材料.
Li1＋xV3O8 as cathode material for lithium-ion battery was synthesized through a solid-state reaction method with Li2CO3 and V2O5 as raw materials. The influence of synthetic conditions on the structure, conductivity and electrochemical properties of Li1 ＋xV3O8 specimens was investigated by means of TG-DTA, XRD, AC impedance and galvanostatic charge discharge tests. XRD results indicated that the relative intensity of the （100） diffraction peak of specimens increases with sintering temperature, thus lengthening the path to intercalate and deintercalate Li^＋ ion from Li1＋xV3O8. The AC impedance testing showed that the conductivity increases with sintering temperature, and the conductivity tends to increase first then decrease with sintering time. Electrochemical testing results indicated that the cathode material sintered at 580 ℃ for 20 hr in air has better electrochemical properties with a maximum discharge specific capacity up to 254.0 mAh.g^-1 which will be kept at 245.6 mAh.g^-1 after 10 cycles. All the testing results showed that the synthesis process proposed can provide an cathode material superior than that prepared by high-temperature melting process. It＇s really an ideal process.
出处
《东北大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2006年第4期434-437,共4页
Journal of Northeastern University(Natural Science)
基金
辽宁省科技厅基金资助项目(2003224005)
