Process method for preparing lithium battery diaphragm by using 3D printing technology

Abstract

The invention relates to a process method for preparing a lithium battery diaphragm by using a 3D printing technology. The method comprises the following steps: A) uniformly mixing a diaphragm base material, an ultrafine ceramic powder and one of PVDF and PMMA in a blender mixer according to a required ratio, transferring into a grinding machine, and grinding to obtain a mixed material with required granularity; B) transferring the obtained mixed material into a heater with a stirring function, heating to melt the material, adding an organic solvent to adjust viscosity of the material, and stirring for 2-5 hours; and C) transferring the molten material into a material injector of a 3D printer, pushing a piston of the injector to enable the material to be sprayed on a substrate in a certainshape and thickness through a spray head of the 3D printer, peeling off the material from the substrate after complete cooling, curing and molding, and rolling to obtain the multifunctional compositediaphragm embedded with the ultrafine nano ceramic powder. The method has the beneficial effect that the thickness-controllable multifunctional composite diaphragm embedded with the ultrafine nano ceramic powder is obtained by applying the 3D printing technology.

Description

technical field [0001] The invention belongs to the field of lithium ion batteries, and in particular relates to a process method for preparing lithium battery separators by using 3D printing technology. Background technique [0002] With the increasing prosperity of consumer electronics, electric vehicles, energy storage systems and other fields, the performance and cost of lithium-ion batteries have greatly restricted the development of these fields. Diaphragm, as one of the four main materials of lithium-ion batteries, has always been concerned by people. The research work on its performance development and cost reduction has not stopped, especially functional ceramic diaphragms, organic material coated diaphragms and these two The composite diaphragm of the material is the mainstream of the current market. [0003] However, due to the limitation of technology and materials, there are some problems to be solved in the existing separators: 1) The pore formation of the bas...

AI Technical Summary

Problems solved by technology

[0003] However, due to the limitation of technology and materials, there are some problems to be solved in the existing separators: 1) The pore formation of the base film is not uniform, and local defects are inevitable; 2) The inorganic material ceramic separator, PVDF or PMMA coating film coating The thickness is uneven, the coating process is complicated, and the coating is easy to fall off; 3) The thin-layer diaphragm has a large heat shrinkage; 4) The coating process is prone to produce inorganic waste residue, organic solvent discharge and other environmental problems; 5) The thickness of the diaphragm is difficult to control; 6 ) The process is complex and the processing cost is high

Its shortcomings are: 1) The process is complicated, and the base film needs to be made first, then the slurry is prepared, and then the modified coating material is coated on the base film by one or more coating methods; 2) The coating material It is easy to fall off, and the coating has local defects; 3) The thickness of the coating is not easy to control; 4) The loss of the base film is large, and the production cost is high; 5) The preparation of the thin-layer separator is difficult, and the heat shrinkage is large at high temperature

This process can produce a multi-functional composite diaphragm at one time, but its thickness is difficult to control, the width is narrow, the local thickness is uneven, the pores are not uniform, and local defects are prone to exist.

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