Hard carbon microspheres as well as preparation method and application thereof

[0081] (1) Take 5g lignin, 10g mass fraction is 50% phenolic resin aqueous solution, be mixed with massfraction and be 15% aqueous solution (the total mass of lignin and phenolic resin accounts for 15% of aqueous solution gross mass), and at room temperature Stir for 1h;

[0082] (2) Transfer the aqueous solution of step (1) to the spray drying equipment, when the air inlet temperature is 150°C, the air outlet temperature is 90°C, and the ring air volume is 100mL min -1 , the inflow volume is 200ml h -1 Under the conditions of spray drying, the precursor nanospheres are obtained;

[0083] (3) Place the precursor nano-microspheres in an inert atmosphere, transfer them to an alumina crucible, place it in the center of a tube-type resistance furnace, and continuously pass in argon gas for protection. Then increase the temperature from room temperature to 1400 °C at a heating rate of 2 °C / min, and carbonize at a constant temperature of 1400 °C for 1 h, then naturally cool to room

[0086] (1) take by weighing 3g lignin, 14g mass fraction is 50% phenolic resin aqueous solution, is mixed with the mass fraction and is 15% aqueous solution (the total mass of lignin and phenolic resin accounts for 15% of aqueous solution gross mass), and at room temperature Stir for 3h;

[0087] (2) Transfer the aqueous solution of step (1) to the spray drying equipment, when the air inlet temperature is 140°C, the air outlet temperature is 90°C, and the ring air volume is 150mL min -1 , the inflow volume is 300ml h -1 Under the conditions of spray drying, the precursor nanospheres are obtained;

[0088] (3) Place the precursor nano-microspheres in an inert atmosphere, transfer them to an alumina crucible, place it in the center of a tube-type resistance furnace, and continuously pass in argon gas for protection. Then increase the temperature from room temperature to 1400 °C at a rate of 2 °C / min, and carbonize at a constant temperature of 1400 °C for 2 hours, then naturally

[0091] (1) take by weighing 7g lignin, 6g mass fraction is 50% phenolic resin aqueous solution, is mixed with the mass fraction and is 15% aqueous solution (the total mass of lignin and phenolic resin accounts for 15% of aqueous solution gross mass), and at room temperature Stir for 1h;

[0092] (2) Transfer the aqueous solution of step (1) to the spray drying equipment, when the air inlet temperature is 130°C, the air outlet temperature is 80°C, and the ring air volume is 200mL min -1 , the inflow volume is 250ml h -1 Under the conditions of spray drying, the precursor nanospheres are obtained;

[0093] (3) Place the precursor nano-microspheres in an inert atmosphere, transfer them to an alumina crucible, place it in the center of a tube-type resistance furnace, and continuously pass in argon gas for protection. Then increase the temperature from room temperature to 1400 °C at a rate of 2 °C / min, and carbonize at a constant temperature of 1400 °C for 3 hours, then naturally