Quick test technique for electrochemical performances of carbon anode materials

Abstract

A quick test technique for electrochemical performances of carbon anode materials comprises the following steps: a, the carbon anode materials to be tested and electrode plate dressing are evenly coated on copper foils by the areal density of 0.6-1.0 g / dm<2>, and are dried to form electrode plates, wherein the electrode plate dressing is prepared by conductive agent, binding agent and thickening agent; b, the electrode plates are rolled by the compacting density of 1.1-1.5 g / cm<3> and are cut to electrode plates which are needed by half cells; c, half cell modules are assembled by the sequence of anode casings, electrode plates, diaphragms, lithium plates, washers and cathode covers, and are sealed under the pressure of 70-85 MPa to form the half cells; and d, the half cells are divided into a normal group and an experimental group for testing through a test cabinet, the test is implemented for one time or is circulated for a plurality of times, and judging whether the first charge-discharge gram specific capacity and the first charge-discharge efficiency of the carbon anode materials meet the requirements or not according to test results is carried out. The technique can easily, quickly and accurately test the electrochemical performances of the carbon anode materials, and can effectively reduce the test cost of the electrochemical performances of the carbon anode materials.

Description

【Technical field】 [0001] The invention relates to a method for testing the electrochemical performance of a carbon negative electrode material, in particular to a rapid testing process for the electrochemical performance of a carbon negative electrode material that can be easily, quickly and accurately tested. 【Background technique】 [0002] Carbon anode materials have typical layered structure characteristics. In the graphite layer, the carbon atoms are arranged in a hexagonal ring and extend to the two-dimensional direction. Each carbon atom between the same layer and its adjacent three carbon atoms sp 2 The hybrid strong σ bond structure exists, and the structure is very stable; between graphite layers, carbon-carbon is only combined by weak Van der Waals force (Vander Waals), and the layer spacing is about 0.34nm. Due to the weak binding force between graphite layers and the large space, it is easy to insert other metal or non-metal molecules, atoms, ions or ion groups ...

AI Technical Summary

Problems solved by technology

[0004] The general test process for half-batteries made of carbon negative electrode materials is 0.05C discharge and 0.1C charge, and the test time takes about 34 hours. Difficult to meet incoming inspection requirements

At the same time, from the perspective of assembly, the half-cell with carbon negative electrode material as the positive electrode is much more difficult than other materials, and the success rate is reduced by 50%.

Because when lithium ions are intercalated into the carbon negative electrode material, excess lithium ions will be precipitated on the surface of the carbon negative electrode material; when the excess is more, the more lithium will be precipitated, and it will slowly grow into lithium dendrites, which are easy to pierce the separator and cause a short circuit

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