Fabrication Of Spinel-Type Bimetallic Oxides And Their Applications In Lithium Primary Batteries

Nowadays,diverse rechargeable lithium secondary battery systems have attracted worldwide attention because of their pretty good cycle ability,however,due to their limited energy and power density,they could not satisfy use demands for some special equipment.Therefore,design and development of a battery systems owning high energy and power density were still a knotty issue need to be solved in the energy storage domain.Comparing to secondary battery systems,the primary battery systems based on irreversible electrochemical reactions generally possess superior performances in energy and power density,thus investigation and exploitation for primary battery systems were rather significant for practical utilization.Metal lithium owned the lowest mass density but the highest energy density in comparison with other metal materials,such as metal sodium and metal magnesium,so the lithium metal primary batteries have great potential in energy and power density.In this work,we successfully fabricated two kinds of novel spinel-type bimetallic oxides,which were further used as cathode materials in lithium metal primary battery,and the cathodes exhibited outstanding performances in both energy and power density.In this work,we fabricated CuFe₂O₄ and Cu Mn₂O₄ via solid state method and optimized them by adjusting calcination temperature and raw material ratio.According to the X-ray diffraction measurements,when the molar ratio of Cu and Mn was 1:3 and the calcination temperature was set as 1000℃,the obtained samples exhibited the highest crystalline degree but with a relatively larger particle size.The optimized calcination temperature for Cu Fe₂O₄ was 900℃,while the most suitable molar ratio of Cu and Mn for Cu Mn₂O₄ was 1:3,and the cathodes delivered discharge capacities of2145.73 and 2614.40 m Ah·g^-1,respectively.Meanwhile,the energy densities of the Cu Fe₂O₄ and the Cu Mn₂O₄ cathodes were 480.79 and 419.04 Wh·kg^-1,respectively.In order to investigate discharge mechanism of the battery,we trace the evolution of the cathode during discharge process with the aid of quasi in-suit X-ray photoelectroscopy analysis,and from the results can we exactly learn about the variation of metal valence.Furthermore,for the propose of improving power density of the cathode,carbon nanotube（CNT）was introduced in Cu Mn₂O₄ material as efficient electronic conductor to enhance its electrical conductivity.After the CNT impregnation,the power density of the cathode increased from 202.47 to 467.19 W·kg^-1.Moreover,the composited material was utilized in a pouch cell and can still remain a power density of 410.09W·kg^-1,indicating the cathode material was potential for practical application and was significant for lithium metal primary battery.