【摘要】 用X射线衍射仪检测不同锂含量的二氧化锰高温化学及随后的电化学锂化过程中的晶体结构的变化 ;模拟锂硼合金阳极的热电池分析其阴极放电性能。41 0℃化学锂化时 ,随Li,Mn原子比的提高 ,β相结构的二氧化锰经层状的锂化二氧化锰结构 ,转向尖晶石型结构 ;750℃长时间保温 ,锂化二氧化锰转变成LiMn2 O4尖晶石和Mn2 O3。50 0℃电化学嵌锂时 ,也生成过渡相LixMnO2 和最终相LiMn2 O4尖晶石 ,其阴极放电电压与锰的初始价态不敏感 ,过电位主要取决于晶体结构中锂离子的扩散通道更多还原

【Abstract】 Changes of crystal structure of manganese dioxide during chemical and following electrochemical lithiation at high temperatures were determined using X ray diffractometer, and the cathodical discharge properties of the compounds were analysed by simulating thermal batteries with a lithium boron alloy anode. After chemically lithiated at 410 ℃, with the increase of Li/Mn molar ratio, β MnO 2 turns to spinel structure compounds through layered lithiated manganese dioxide which can change to spinel compounds and Mn 2O 3 if long time exposed at 750 ℃. Intermediate phase Li xMnO 2 and final spinel phase LiMn 2O 4 also occurred if MnO 2 or Li xMnO 2 were electrochemically lithiated at 500 ℃. The voltage of chemically lithiated compounds was not sensitive to Mn’s initial valence when they were cathodically discharged, while over potential was dependent mainly on the channels in which lithium ions can diffuse inside the crystals.更多还原