ELECTRODE PLATE AND PREPARATION METHOD THEREOF, SECONDARY BATTERY AND ELECTRICAL DEVICE
An electrode plate, which includes a current collector and an active material layer arranged on at least one surface of the current collector. The active material layer includes an electrode active material and a softener. The softener includes one or more of A diblock copolymer A-B and a triblock copolymer A-B-A, where block A includes a polyether segment, and block B includes one or more of a polyamide segment, a polyvinylpyrrolidone segment and a polyacrylonitrile segment.
1 . An electrode plate comprising:
a current collector; and
an active material layer, disposed on at least one surface of the current collector, and comprising:
an electrode active material; and
a softener, comprising one or more of a diblock copolymer A-B and a triblock copolymer A-B-A,
wherein block A comprises a polyether segment, block B comprises one or more of a polyamide segment, a polyvinylpyrrolidone segment and a polyacrylonitrile segment.
2 . The electrode plate according to claim 1 , wherein the polyether segment comprises one or more of a polyethylene glycol segment, a polypropylene glycol segment, a polytetramethylene glycol segment and a polypentylene glycol segment.
3 . The electrode plate according to claim 1 , wherein a ratio of a degree of polymerization of the block A to the block B is (2˜50):1.
4 . The electrode plate according to claim 1 , wherein a ratio of a degree of polymerization of the block A to the block B is (2˜25):1.
5 . The electrode plate according to claim 1 , wherein the degree of polymerization of the block A is in a range of 4 to 2000.
6 . The electrode plate according to claim 1 , wherein the degree of polymerization of the block A is in a range of 4 to 800.
7 . The electrode plate according to claim 1 , wherein the degree of polymerization of the block B is in a range of 2 to 1000.
8 . The electrode plate according to claim 1 , wherein the degree of polymerization of the block B is in a range of 2 to 400.
9 . The electrode plate according to claim 1 , wherein a weight-average molecular weight of the softener ranges from 1000 Da to 200000 Da.
10 . The electrode plate according to claim 1 , wherein, in the active material layer, a mass percentage of the softener is in a range of 0.02% to 3.
11 . The electrode plate according to claim 1 , wherein the softener is a polyether-polyamide-polyether block copolymer;
optionally, the polyether segment comprises one or more of a polyethylene glycol segment and a polypropylene glycol segment; and
optionally, the polyamide segment comprises one or more of an aliphatic polyamide segment and an aromatic polyamide segment.
12 . The electrode plate according to claim 1 , wherein the softener has a structure shown in formula I:
wherein, each occurrence of R 1 is independently selected from an aliphatic alkylene group having 2 to 5 carbon atoms in a main chain;
occurrences of R 2 and R 3 , at each time, are independently selected from one of an aliphatic alkylene group having 2 to 14 carbon atoms in the main chain and an aromatic alkylene group having 6 to 10 carbon atoms in the main chain, or a combination thereof, respectively;
each occurrence of x is independently selected from any integer within a range of 4 to 800; and
y is selected from any integer within a range of 2 to 400.
13 . The electrode plate according to claim 1 , wherein the electrode plate is a positive electrode plate, and a compaction density of the electrode plate is in a range of 2.40 g/cm 3 to 3.75 g/cm 3 .
14 . The electrode plate according to claim 1 , wherein the electrode plate is a negative electrode plate, and a compaction density of the electrode plate is in a range of 1.50 g/cm 3 to 1.80 g/cm 3 .
15 . The electrode plate according to claim 1 , wherein the electrode plate is a positive electrode plate, and a resistance of the electrode plate is ≤1.5Ω; and optionally, the resistance of the electrode plate is ≤0.8Ω; further optionally, the resistance of the electrode plate is ≤0.5Ω.
16 . The electrode plate according to claim 1 , wherein the electrode plate is a negative electrode plate, and a resistance of the electrode plate is ≤0.05Ω; and optionally, the resistance of the electrode plate is ≤0.02Ω.
17 . A method for making the electrode plate according to claim 1 comprising:
mixing the electrode active material, the softener and a solvent to prepare an electrode slurry; and
coating the electrode slurry on at least one surface of the current collector, drying and pressing.
18 . The method according to claim 17 , wherein a viscosity of the electrode slurry ranges from 4000 mPa·s to 35000 mPa·s.
19 . A secondary battery, comprising the electrode plate according to claim 1 .
20 . An electrical device, comprising the secondary battery according to claim 19 .