Manufacture Of Lithium-ion Battery Based On Transition Metal Oxides Micro/nanostructured Materials

Owing to the advantages of high energy density,large power density,low self-discharge rate and pollution-free emission,lithium ion batteries?LIBs?are regarded as“promising chemical power sources”in the 21st century.Transition metal oxides?TMOs?possessing many advantages,such as high theoretical capacities,abundant sources,low cost,and easy preparation,have been regarded as promising anode materials for LIBs.However,its poor conductivity and large volume change during Li⁺insertion/extraction lead to poor cycle life,which hinders their commercial applications.The combination of transition metal oxides and other materials to build nanostructured composites can effectively ameliorate the above problems.In this work,we focused our attention on preparation of the following electrode materials and study of their electrochemical properties.?1?Co₃O₄/Li₂TiO₃ composite hollow nanofibers with different molar ratios of Co to Ti were successfully synthesized for the first time by using electrospinning technology and post-annealing treatment.Lithium ion battery was constructed by Co3O4/Li2TiO3 composite hollow nanofibers as anode material.When the molar ratio of Co to Ti was 10:1,the Co3O4/Li2TiO3 composite hollow nanofibers exhibit the best electrochemical performance.It exhibits a high initial discharge specific capacity of 1035 mAh g^-1 at 100 mA g^-1,and the capacity can reach 1728.9 mAh g^-1 after 212 cycles.Even at 1 A g^-1,its average specific discharge capacity still be reached 1039.3 mAh g^-1??2?Li2TiO3 nanofibers were prepared by electrospinning and then hydrothermally growing Co₃O₄ porous nanosheets on Li₂TiO₃ nanofibers to obtain a series of Co₃O₄/Li₂TiO₃composites.When applied as anode materials for LIBs,the Co3O4/Li2TiO3 composite with20 mg Li2TiO3 delivers the best electrochemical performance.Its first discharge specific capacity is 1495.6 mAh g^-1 at 100 mA g^-1.After 248 cycles,its specific discharge capacity is1348.7 mAh g^-1,keeping 90%of its initial discharge capacity.It also has good rate capability.?3?NiO hollow nanofibers were prepared by electrospinning technique and then mixed with aqueous dispersion of graphene to obtain a series of NiO/Graphene composites.Using NiO/Graphene composites as anode material for LIBs,when the mass ratio of NiO to Graphene was 1:1,NiO/Graphene composite shows the best electrochemical performance,including high initial discharge capacity(1085.9 mAh g^-1),good cycling performance(1397.9 mAh g^-1 after 300 cycles at 100 mA g^-1),and outstanding rate performance(814.9mAh g^-1 at the current densities of 2 A g^-1).