Siloxane-terminated polyether type lithium battery adhesive and preparation method thereof

Abstract

The invention discloses a siloxane-terminated polyether type lithium battery adhesive and a preparation method thereof. The preparation method comprises the following steps: 1) sequentially adding a solvent and cyanate into a reaction bottle, performing stirring and mixing, further adding a phase transfer catalyst, performing heating to 70-100 DEG C, and performing uniform constant temperature activation and dispersion for 30 minutes; and 2) respectively dropwise adding measured chlorosilane and polyether alcohol, or chlorosilane and polyester alcohol into the activation solution in the step 1), increasing the exothermic reaction temperature to 90-120 DEG C, maintaining the temperature range, performing a continuous reaction for 6-8 hours, after the reaction is completed, performing cooling to the room temperature, performing filtering so as to obtain filtrate, and removing the solvent, so as to obtain the siloxane-terminated polyether type lithium battery adhesive. The siloxane-terminated polyether type lithium battery adhesive disclosed by the invention is simple in preparation method, low in cost, high in efficiency, fast in adhesion and easy in industrialization. Prepared siloxane-terminated polyether for adhesion of lithium batteries is capable of improving the efficiency of the lithium batteries, high and low temperature resistance, stable charge and discharge efficiencyand bonding properties of the lithium batteries.

Description

technical field [0001] The invention relates to an adhesive used in the field of lithium battery materials, in particular to a siloxane-terminated polyether type lithium battery adhesive and a preparation method thereof. Background technique [0002] Due to its high energy density, lithium-ion batteries have played an increasingly important role in the field of new energy. The energy density of lithium-ion batteries exceeds 150WhKg -1 , which is higher than almost all known energy densities in secondary batteries. In order to further improve the performance of lithium-ion batteries, it is necessary to find new electrode materials, electrolytes, and additives. However, the efficiency of lithium-ion batteries depends largely on the optimization of electrode preparation conditions. One of the most important aspects is to find the most suitable electrodes. of adhesives. The binder is a very important part of the positive and negative electrode materials of lithium batteries. I...

AI Technical Summary

Problems solved by technology

However, there are many defects in these organic solvent-based binders. PVDF-type binders need to take a large amount of NMP solvent to dissolve, and often when the concentration of PVDF is 10-20%, the slurry shows an abnormally high-viscosity behavior. It makes the preparation of the electrode composition difficult. At the same time, because NMP is used as the solvent, on the one hand, it is difficult to volatilize, time-consuming, and the process is complicated; on the other hand, the organic solvent is toxic and flammable, causing environmental pollution and safety problems.

[0005] U.S. Patent US20120153219 describes a polyether-modified siloxane binder, which overcomes the above-mentioned molecular structure deficiency of polar and non-polar lithium battery electrodes, not only endows good lithium ion migration ability, but also has The electrodes have good bonding stability, but this method uses the method of hydrosilicon addition. If the method of heating vulcanization is not used, the vulcanization needs more than 72 hours, which limits the basis of its wide application.

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