Polyoxometallic acid lithium ceramic diaphragm of lithium ion battery

[0028] Example 1

[0029] A polyoxometalate lithium salt ceramic diaphragm for lithium ion batteries, comprising a polyolefin diaphragm substrate, and the ceramic diaphragm is coated on the surface of the polyolefin diaphragm substrate with Al containing polyoxometalate lithium salt 2 O 3 Composite ceramic powder.

[0030] The lithium polyoxometalate is Li 3 XY 12 O 40 Or Li 4 XY 12 O 40 , X refers to any one of the two elements P and Si; Y refers to any one of the two elements Mo and W.

[0031] The polyolefin membrane substrate is a single-layer film of polypropylene (PP) or polyethylene (PE), or a three-layer film composed of two materials.

[0032] The preparation method is: the preparation method of the polymetallic oxide lithium salt ceramic diaphragm is in Al 2 O 3 The pores of the ceramic powder are loaded with polyoxometalate lithium salt, and then the ceramic powder containing the polyoxometalate lithium salt is coated on the polyolefin separator with a coating machine to obtain

[0048] Example 2

[0049] The preparation method is:

[0050] 1. Li 3 PW 12 O 40 -Al 2 O 3 Preparation of composite ceramic powder

[0051] Will Al 2 O 3 Ceramic powder and lithium phosphotungstate Li 3 PW 12 O 40 Weigh according to the mass ratio of 10:5, and the Al 2 O 3 Ceramic powder impregnated in lithium phosphotungstate Li 3 PW 12 O 40 After 4 hours in anhydrous methanol solution, it was filtered out and evaporated to dryness in a water bath at 60°C. After preliminary drying, it was baked at 80°C for 4 hours and then baked at 200°C for 3 hours to obtain Li 3 PW 12 O 40 -Al 2 O 3 Composite ceramic powder.

[0052] 2. Preparation of ceramic diaphragm

[0053] According to polyvinylidene fluoride (PVDF, HSV900) and Li 3 PW 12 O 40 -Al 2 O 3 The ratio of composite ceramic powder is 1:20. Stir evenly in N-methylpyrrolidone (NMP) and configure it into a slurry. Then transfer the slurry to the diaphragm substrate on the coating machine to form a 2um coating. The coating machine i

[0055] Example 3

[0056] 1. Li 4 SiW 12 O 40 -Al 2 O 3 Preparation of composite ceramic powder

[0057] Will Al 2 O 3 Ceramic powder and lithium silicotungstate Li 4 SiW 12 O 40 Weighed according to the mass ratio of 10:3, and the Al 2 O 3 Ceramic powder immersed in lithium silicotungstate Li 4 SiW 12 O 40 Filter out after 24 hours in anhydrous methanol solution, evaporate to dryness in a water bath at 100°C. After initial drying, bake at 160°C for 3 hours, and then bake at 1000°C for 1 hour to obtain Li 4 SiW 12 O 40 -Al 2 O 3 Composite ceramic powder.

[0058] 2. Preparation of ceramic diaphragm

[0059] According to polyvinylidene fluoride (PVDF, HSV900) and Li 4 SiW 12 O 40 -Al 2 O 3 The composite ceramic powder has a ratio of 1:15, stirs uniformly in N-methylpyrrolidone (NMP), and configures it into a slurry, and then transfers the slurry to the diaphragm substrate on a coating machine to form a 10um coating. Coater oven is dried at 80°C and reeled for later use.

[0060] T