摘要
以LiNO_(3)、Ni(NO_(3))2·6H_(2)O、Mn(NO_(3))_(2)为主要原料,尿素作燃料,采用低温燃烧法合成了亚微米级、电化学性能良好、单晶形貌的5 V锂离子电池正极材料LiNi_(0.5)Mn_(1.5)O_(4)。考察了不同回火温度对所合成产物的结构、形貌和电化学性能的影响,并通过X射线衍射、扫描电镜和充放电实验对不同回火温度下合成的产物进行了表征。实验结果表明,在不同回火温度得到的样品均具有尖晶石结构。但是在回火温度为800℃和900℃下合成的样品产生了较多的杂质相,随着回火温度的升高,合成产物的结晶度逐渐提高,粒径逐渐增大。在回火温度为850℃得到的样品成清晰的八面体外形,结晶良好,粒径适中,在3.5~4.9 V内0.1 C倍率下首次放电容量最高,30次循环后其容量保持率最好,其电化学性能最好。
Using LiNO_(3),Ni(NO_(3))2·6H_(2)O,Mn(NO_(3))_(2)as main raw materials,and urea as fuel,the submicron cathode material LiNi_(0.5)Mn_(1.5)O_(4)for 5V lithium-ion batteries with sub-micron,good electrochemical performance and single crystal morphology is synthesized by low-temperature combustion process.The effects of different tempering temperatures on the structure,morphology and electrochemical properties of the synthesized products are investigated.The products are characterized by XRD,SEM and charge-discharge test.The experimental results show that the samples obtained at different tempering temperatures all have spinel structure,but the samples synthesized at 800℃and 900℃produce more impurity phase.With the increase of tempering temperature,the crystallinity of the synthesized products gradually increases,and the particle size gradually increases.The samples obtained at 850℃have clear octahedral shape,good crystallization and moderate particle size.The first discharge capacity is the highest at 0.1 C rate in the range of 3.5~4.9 V,the capacity retention rate is the best after 30 cycles,and the electrochemical performance is the best.
作者
赵巧丽
李龙
ZHAO Qiaoli;LI Long(Panjin Vocational and Technical College,Panjin 124000,China)
出处
《河南化工》
CAS
2023年第9期33-35,41,共4页
Henan Chemical Industry
