The invention relates to the field of
sodium ion secondary batteries, and provides a method for regulating and controlling a hard carbon
structure based on
transition metal manganese, which is used for a
sodium ion battery negative
electrode material. Cheap and easily available
biomass is used as a
carbon source, and
manganese is ensured to be uniformly dispersed in a
precursor polymer through coordination of
manganese ions (Mn < 2 + >) and one-dimensional
cellulose nanofibers and a coordination effect; according to the present invention, the
graphene sheets are introduced into the
graphene sheets, such that the conversion between the SP3 carbon and the SP2 carbon is effectively catalyzed so as to freely rearrange the
graphene sheets, such that the expanded nano-
graphite and the carbon micro-pores are formed, and the controllable adjustment of the carbon interlayer spacing and the micro-pores is achieved by adjusting the concentration; and finally, 92.05% of ultrahigh first efficiency and excellent circulating performance are obtained (the capacity
retention ratio of 200 cycles is 95.80% under the
current density of 20mA g <-1 >). The problems of
low sodium ion first efficiency and poor
cycling stability are solved through ion
catalysis regulation and control, the first efficiency can be improved to 90% or above, the performance is improved by 30% or above, the
energy density of the battery is greatly improved, and the total battery with
sodium vanadium phosphate as the positive
electrode has excellent electrochemical performance, has a good industrialization prospect and is suitable for industrial production. The method is very suitable for large-scale
energy storage systems.