A method for preparing high-voltage flexible lithium-ion batteries with electrophobic carbon nanotube films

Abstract

The invention discloses a method for preparing a high-voltage flexible lithium-ion battery with an electrophobic electrolyte carbon nanotube film, and relates to a preparation method for a flexible lithium-ion battery. The following steps are sequentially included: Step 1, carbon nanotube film nano-fluoride layer coating; Step 2, electrode preparation and assembly; Step 3, cell injection electrolyte solution. The present invention has the following beneficial effects: the present invention covers the surface of carbon nanotubes with a fluorinated layer of nanometer thickness to prevent lithium ions from entering the interior of carbon nanotubes, avoiding irreversible reactions with them, thereby improving the reversible capacity of the battery. And assembled into a full battery has good flexibility, and still maintains good electrochemical performance under severe deformation conditions such as folding and rubbing. The invention has simple preparation process, low production cost, and the preparation process is close to the industrialization level; the obtained flexible battery has high working voltage and strong battery life, which can be compared with traditional lithium ion batteries.

Description

technical field [0001] The invention relates to a method for preparing a flexible lithium-ion battery, in particular to the preparation of an electrophobic carbon nanotube film and using it as a current collector for the negative electrode active material of the lithium-ion battery, so as to improve the working voltage of the existing flexible lithium-ion battery of a technique. Background technique [0002] With the rapid development of wearable electronic products, mobile portable electronic devices have penetrated into every aspect of daily life, and people always try to enjoy the convenience brought by the Internet anytime and anywhere through portable mobile electronic devices. At present, some conceptual and prototype flexible electronic products have come out one after another, such as Huawei 5G folding screen mobile phone, flexible smart bracelet, Google Glass and Apple smart watch, etc. The matching power supply system is the prerequisite for realizing the applicat...

AI Technical Summary

Problems solved by technology

The performance of the battery does not change during the folding process, the preparation process is close to the industrial level, and the safety performance is high, but its working voltage is only 2.4 V, which is difficult to meet the needs of high energy density of commercial products

Although flexible lithium-ion batteries with high specific capacity and good stability can be prepared in the above studies, the voltage is not high, and the method of increasing the voltage can only sacrifice its specific capacity, which ultimately leads to a low increase in battery energy density.

The root cause of the above problems is that the flexible current collector materials used above have lithium ion intercalation potentials at 1.0 V and 0.1 V. Therefore, only a negative electrode material with a relative lithium potential higher than 1.0 V is selected to coat the current collector. The electrochemical performance is normal, but the high-potential negative electrode material will lead to a drop in the working voltage of the battery

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