POSITIVE ELECTRODE PLATE FOR SECONDARY BATTERY AND SECONDARY BATTERY
Provided are a positive electrode plate for secondary battery, a manufacturing method thereof, and a secondary battery, battery module, battery pack, and electric apparatus using such positive electrode plate for secondary battery. The positive electrode plate for secondary battery includes a current collector and a positive electrode active substance layer and further includes a porous layer containing a porous carbon material between the current collector and the positive electrode active substance layer.
1 . A positive electrode plate for secondary battery, characterized by comprising:
a current collector and a positive electrode active substance layer, and further comprising a porous layer containing a porous carbon material between the current collector and the positive electrode active substance layer.
2 . The positive electrode plate for secondary battery according to claim 1 , characterized in that
the porous carbon material is selected from at least one of hard carbon, biomass carbon, activated carbon, carbon fiber, and carbon aerogel.
3 . The positive electrode plate for secondary battery according to claim 1 , characterized in that
the positive electrode plate for secondary battery is formed by the current collector, the porous layer, and the positive electrode active substance layer.
4 . The positive electrode plate for secondary battery according to claim 1 , characterized in that
the positive electrode active substance layer contains lithium nickel cobalt manganese oxide; and
the porous carbon material is hard carbon, activated carbon, or carbon aerogel.
5 . The positive electrode plate for secondary battery according to claim 1 , characterized in that
the porous carbon material comprises micropores, mesopores, and macropores, wherein pore diameter of the micropores is 2 nm or below, pore diameter of the mesopores is greater than 2 nm and less than 50 nm, and pore diameter of the macropores is 50 nm or above.
6 . The positive electrode plate for secondary battery according to claim 5 , characterized in that
in the porous carbon material, a total pore volume of the micropores, mesopores, and macropores is 0.02 cm 3 /g or above, and a summed-up pore volume of the micropores and mesopores accounts for 5%-85% with respect to the total pore volume.
7 . The positive electrode plate for secondary battery according to claim 1 , characterized in that
D v 50 of the porous carbon material is 1 μm-100 μm.
8 . The positive electrode plate for secondary battery according to claim 1 , characterized in that
a ratio of a specific surface area of the positive electrode plate under carbon dioxide atmosphere to a specific surface area of the positive electrode plate under nitrogen atmosphere is 2 or above.
9 . The positive electrode plate for secondary battery according to claim 8 , characterized in that
the specific surface area of the positive electrode plate under carbon dioxide atmosphere is 2 m 2 /g or above, and the specific surface area of the positive electrode plate under nitrogen atmosphere is 1 m 2 /g or below.
10 . The positive electrode plate for secondary battery according to claim 1 , characterized in that
under a condition that thickness of the positive electrode active substance layer is set to 100 parts by thickness, thickness of the porous layer accounts for 1-50 parts by thickness.
11 . The positive electrode plate for secondary battery according to claim 1 , characterized in that
the positive electrode plate has pores in surface of a side on which the positive electrode active substance layer is provided, wherein
pore diameter of the pores exhibits a maximum circumferential diameter distribution of 1 μm-50 μm.
12 . A manufacturing method of the positive electrode plate for secondary battery according to claim 1 , characterized by comprising:
a process of forming the porous layer containing the porous carbon material on surface of at least one side of the current collector; and
a process of applying a positive electrode slurry on the formed porous layer to form the positive electrode active substance layer.
13 . The manufacturing method of the positive electrode plate for secondary battery according to claim 12 , characterized in that
the porous layer is formed by a slurry comprising the porous carbon material, acetylene black as a conductive agent, polyvinylidene fluoride as a binder, and N-methylpyrrolidone as a solvent.
14 . A secondary battery, characterized by comprising the positive electrode plate according to claim 1 .
15 . A secondary battery, characterized by comprising the positive electrode plate manufactured using the manufacturing method according to claim 12 .