Inorganic adhesive treated copper-aluminum current collector and manufacturing method of battery cell of inorganic adhesive treated copper-aluminum current collector

Abstract

The invention relates to a manufacturing method of a copper-aluminum current collector treated by an inorganic adhesive and a battery cell thereof, which comprises the following manufacturing steps of: manufacturing a mixed solution of the inorganic adhesive and a conductive agent, namely putting 100 parts by weight of copper oxide, 25 parts by weight of phosphate glue and 10 parts by weight of aluminum phosphate into a stirring container, uniformly stirring, adding 50 parts by weight of deionized water, adding CNT water-based conductive slurry with the solid content of 4.2%, and uniformly stirring to obtain the mixed solution of the inorganic adhesive and the conductive agent; stirring for 4-6 hours to obtain a mixed solution of the inorganic adhesive and the conductive agent; respectively coating a copper foil and an aluminum foil with the mixed solution of the inorganic adhesive and the conductive agent, drying at 90-100 DEG C, and rolling; a ternary or lithium iron phosphate active material is coated on an aluminum foil containing a mixed solution of an inorganic adhesive and a conductive agent, graphite or silicon carbon is coated on a copper foil containing the mixed solution of the inorganic adhesive and the conductive agent, and a battery cell is assembled. The present invention can improve cycle life and continuity of cycle life production, etc.

Description

Technical Field

[0001] The invention relates to a copper-aluminum current collector treated with an inorganic adhesive and a method for manufacturing an electric core thereof. Background Art

[0002] With the extensive application of lithium-ion batteries in power and large-scale energy storage, the capacity and power of single cells are getting larger and larger, requiring longer battery life and wider ambient temperature tolerance. The adhesion between the positive and negative collector aluminum copper foil and the active powder material interface of the battery cell is required to be more and more stable to meet the 20-year life cycle. Traditional organic adhesives cannot meet the long-term electrolyte erosion, temperature changes, shrinkage and expansion stress changes, oxidation of the cathode at full charge and reduction of the anode, and lose adhesion, increase the internal resistance of the battery, and greatly deteriorate the service life of power and energy storage batteries. Summary of the invention

[0003] The purpose of the present invention is to solve the essential problem of organic adhesives losing their viscosity due to aging caused by temperature, stress, oxidation and reduction by using inorganic adhesives.

[0004] The invention discloses a method for preparing a copper-aluminum current collector treated with an inorganic adhesive and a battery cell thereof, which comprises the following steps: preparing a mixed solution of an inorganic adhesive and a conductive agent, placing 100 parts by weight of copper oxide, 25 parts of phosphate glue, and 10 parts of aluminum phosphate in a stirring container and stirring them evenly, adding 50 parts of deionized water, adding a CNT aqueous conductive slurry with a solid content of 4.2%, and stirring for 4-6 hours to obtain a mixed solution of an inorganic adhesive and a conductive agent; coating the mixed solution of the inorganic adhesive and the conductive agent on a copper foil and an aluminum foil respectively, and rolling them up after drying at 90-100° C.; coating a ternary or lithium iron phosphate active material on the aluminum foil with the mixed solution of the inorganic adhesive and the conductive agent, coating graphite or silicon carbon on the copper foil with the mixed solution of the inorganic adhesive and the conductive agent, and assembling them into a battery cell.

[0005] Furthermore, the coating thickness of the inorganic adhesive and conductive agent mixed liquid on the copper foil and the aluminum foil after drying is 3-5 microns.

[0006] Take the BT120888699 cell as an example, its capacity is 600Ah, the top seal length is 1000mm, the width is 10mm, the tab length is 800mm*the thickness is 0.5mm, and tabs are provided at both ends. The performance of the cell using the inorganic adhesive of the present invention and that not using the inorganic adhesive of the present invention is as follows.

[0007]

[0008] It can be seen that the battery cell produced by the copper-aluminum current collector treated with an inorganic adhesive and the method for manufacturing the battery cell of the present invention can improve the cycle life and the continuity of cycle life production. DETAILED DESCRIPTION

[0009] As a specific embodiment, the steps for making the copper-aluminum current collector and the battery cell thereof treated with an inorganic adhesive in the embodiment of the present invention are as follows:

[0010] First: Preparation of inorganic adhesive and conductive agent mixture:

[0011] A. Weigh 100g of copper oxide;

[0012] B. Take 25g of phosphoric acid glue;

[0013] C. Take 10g of aluminum phosphate;

[0014] Put it into a stirring container and stir it evenly, add 50g of deionized water, add CNT aqueous conductive slurry with a solid content of 4.2%, stir for 4-6 hours, and test the viscosity and solid content.

[0015] Second: Coat on copper foil and aluminum foil respectively, dry at 90-100℃ and then roll up.

[0016] Third: According to the conventional lithium battery production process, the ternary or lithium iron phosphate active material is coated on the aluminum foil containing an inorganic adhesive, and the graphite or silicon carbon is coated on the copper foil containing an inorganic adhesive. After drying, rolling, assembly and other processes, a large-capacity battery cell (600Ah3.2V or 3.7V) is made.

Claims

1. A method for producing a copper-aluminum current collector treated with an inorganic adhesive and a battery cell thereof, characterized in that: The production steps include: To prepare the inorganic adhesive and conductive agent mixture, 100 parts by weight of copper oxide, 25 parts of phosphate glue, and 10 parts of aluminum phosphate were placed in a stirring container and stirred evenly. 50 parts of deionized water and a CNT aqueous conductive slurry with a solid content of 4.2% were added. The mixture was stirred for 4-6 hours to obtain the inorganic adhesive and conductive agent mixture. The inorganic adhesive and conductive agent mixture is coated on the copper foil and aluminum foil respectively, and then rolled up after drying at 90-100°C; The ternary or lithium iron phosphate active material is coated on the aluminum foil with a mixture of inorganic adhesive and conductive agent, and the graphite or silicon carbon is coated on the copper foil with a mixture of inorganic adhesive and conductive agent, and then assembled into a battery cell.

2. The method for manufacturing the copper-aluminum current collector treated with an inorganic adhesive and the battery core thereof according to claim 1, wherein: The coating thickness of the inorganic adhesive and conductive agent mixture on the copper foil and the aluminum foil after drying is 3-5 microns.

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