Lithium battery diaphragm, preparation method and electrostatic spinning device

Abstract

The invention discloses a lithium battery diaphragm. The lithium battery diaphragm comprises the following components in parts by weight: 93-96 parts of N,N-dimethylamide, 10-13 parts of polyacrylonitrile and 1-2 parts of lithium lanthanite oxide. A preparation method comprises the following steps of 1) mixing the N,N-dimethylamide and polyacrylonitrile powder to prepare a solution; 2) adding lithium lanthanite oxide powder into the mixed solution of the N,N-dimethylamide and the polyacrylonitrile, and carrying out uniform stirring by a stirrer; 3) putting a mixed solution into an electrostatic spinning device, carrying out sequential unidirectional spinning, namely, carrying out transverse reciprocating spinning first, and then carrying out longitudinal reciprocating spinning after the end is reached, until an initial point is reached; and continuing the next spinning to ensure that a fiber has three layers, wherein technological parameters of the electrostatic spinning device are asfollows: an electrostatic voltage is 15-20KV, a jet speed is 0.2-0.71ml / h, and a receiving distance is 16cm; and 4) carrying out vacuum drying on the fiber subjected to spinning forming at 45 DEG C for 5 hours so as to complete the preparation. The lithium battery diaphragm is high in structural strength, high in liquid absorption capacity, high in ionic conductivity, and convenient and fast to prepare.

Description

technical field [0001] The invention relates to a lithium battery, in particular to a lithium battery diaphragm, a preparation method and an electrospinning device. Background technique [0002] The battery cell of a lithium-ion battery is mainly composed of positive electrode material, negative electrode material, separator and electrolyte. Among them, the separator is an important part of the battery cell, which can separate the positive and negative electrodes of the battery, and has electronic insulation and ion conductivity. The performance of the separator determines the interface structure of the battery, the retention of the electrolyte, and the internal resistance of the battery, which in turn affects key characteristics such as the capacity, cycle performance, and charge-discharge current density of the battery. In addition, the separator also has a great influence on the safety of the battery. Therefore, the performance of the separator directly affects the over...

AI Technical Summary

Problems solved by technology

However, due to the existence of strong polar groups such as -CN, the compatibility between PAN and metal electrodes is poor, and serious passivation occurs between the gel polymer electrolyte and the lithium metal electrode, resulting in a gradual increase in the internal resistance of the battery. Affect battery usage

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