CAJ | 학술논문

采用酸处理尖晶石型LiMn_2O_4的方法合成了λ-MnO_2.通过X-射线衍射(XRD)、扫描电子显微镜(SEM)和恒流放电测试等对λ-MnO_2的结构、形貌和电化学性能进行了研究.结果表明,合成的λ-MnO_2具有类似于LiMn2O4的尖晶石型晶体结构,形貌规则,晶粒细小,粒径分布均匀;将其作为正极材料组装成Li-MnO_2电池,以0.025 C倍率放电,得到了3.98 V和2.88 V两个放电平台,放电比容量达268 mAh/g,且其放电平台和比容量受放电倍率影响较小.
채용산처리첨정석형LiMn_2O_4적방법합성료λ-MnO_2.통과X-사선연사(XRD)、소묘전자현미경(SEM)화항류방전측시등대λ-MnO_2적결구、형모화전화학성능진행료연구.결과표명,합성적λ-MnO_2구유유사우LiMn2O4적첨정석형정체결구,형모규칙,정립세소,립경분포균균;장기작위정겁재료조장성Li-MnO_2전지,이0.025 C배솔방전,득도료3.98 V화2.88 V량개방전평태,방전비용량체268 mAh/g,차기방전평태화비용량수방전배솔영향교소.
The λ-manganese dioxide(λ-MnO_2)was synthesized by acidifying spinel lithium manganese dioxide (LiMn_2O_4).The crystalline structure,morphology and electrochemical properties of λ-MnO_2 were investigated by X-ray diffraction,scanning electron microscopy and galvanostatic discharge test.The results show that λ-MnO_2 has the same spinel-type structure like LiMn_2O_4,and it has small particle size,regular morphology,and uniform distribution of particle size.λ-MnO_2 delivers a discharge capacity of 268 mAh/g at a rate of 0.025 C in discharge plateau 3.98 V and 2.88 V.Therefore,λ-MnO_2 is a promising cathode material for primary Li-MnO_2 batteries,and its discharge capacity and discharge plateau are scarcely influenced by discharge rate.