Preparation method of lithium ion capacitor

Abstract

The invention provides a preparation method of a lithium ion capacitor. The preparation method comprises the following steps that: a positive-pole current collector is prepared; 2, a positive-pole electrode sheet is prepared; 3, a negative-pole current collector is prepared; 4, a negative-pole electrode sheet is prepared; 5, a diaphragm is prepared; 6, a material for preparing electrolyte is selected; 7, an aluminum-plastic film is prepared; 8, materials for preparing electrode lugs are selected; and 9, the capacitor is prepared. According to the step 9, the positive-pole electrode sheet, thediaphragm and the negative-pole electrode sheet are laminated so as to form a battery core; the positive-pole electrode lug and the positive-pole current collector are welded by means of ultrasonic soldering; the negative-pole electrode lug and the negative-pole current collector are welded by means of ultrasonic soldering; the battery core is packaged with the aluminum-plastic film at temperaturefrom 100 to 250 DEG C; the electrolyte is injected from a liquid injection opening, the liquid injection opening is sealed; standing, formation, liquid extraction and grading are performed, so that the lithium ion capacitor can be prepared. The energy density of the lithium ion capacitor prepared by using the preparation method of the invention can achieve 60 wh / kg; the voltage of the lithium ioncapacitor ranges from 4.2 to 2.8 V; and the energy density and voltage of the lithium ion capacitor prepared by using the preparation method are significantly improved compared with the energy density and voltage of a general super-capacitor; the internal resistance of the capacitor can be reduced; and the high-rate cycle life of the capacitor can be prolonged.

Description

technical field [0001] The invention relates to the field of manufacturing supercapacitors, in particular to a method for preparing lithium ion capacitors. Background technique [0002] Lithium-ion supercapacitors have the advantages of high voltage, high energy density, high power, low self-discharge, fast charging and discharging, wide operating temperature range, high safety, etc., and are widely used in wind power generation, solar power generation, hybrid vehicles and other fields prospect. Lithium-ion capacitors in the prior art are generally prepared with lithium cobaltate, lithium iron phosphate, etc. as the positive electrode, and rolled foil is used as the positive electrode collector; graphite and lithium titanate are used as the negative electrode, and rolled copper foil is used as the negative electrode collector. This type of lithium-ion supercapacitor usually has a relatively low energy density of 30-40wh / kg, and the internal resistance of the product is gene...

AI Technical Summary

Problems solved by technology

Lithium-ion capacitors in the prior art are generally prepared with lithium cobaltate, lithium iron phosphate, etc. as the positive electrode, and rolled foil is used as the positive electrode collector; graphite and lithium titanate are used as the negative electrode, and rolled copper foil is used as the negative electrode collector. This kind of lithium-ion supercapacitor usually has a relatively low energy density of 30-40wh / kg, and the internal resistance of the product is generally too high, and there are also shortcomings such as low high-rate cycle life.

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