High-capacity organic lithium storage material and application thereof

Abstract

The invention relates to a high-capacity organic lithium storage material. The high-capacity organic lithium storage material is selected from one or a mixture of organic acids with abutenedioic acid conjugated bond structure and salts of the organic acids. By selecting one or the mixture of the organic acids with the butenedioic acid conjugated bond structure and the salts of the organic acids, lithium storage can be realized through transformation of conjugated double bonds in molecular space, not only can lithium-ions be stored on carboxyl groups, but also Li2O can be formed reversibly through chemical bond change of carboxyl sites and stored in electrode micropores, the material contains many active lithium storage sites, and one molecule with a butenedioic acid structure can store 8-12 lithium-ions.

Description

technical field [0001] The invention belongs to the field of battery or supercapacitor electrode materials, and relates to a lithium storage material, in particular to a high-capacity, high-power and long-life organic lithium storage material and its application. Background technique [0002] With the development of power vehicles and large-scale energy storage technology, high-capacity, high-power and long-life batteries and capacitors have become the most promising chemical energy storage power sources. Active materials are the key and core of chemical energy storage devices such as lithium-ion batteries, sodium-ion batteries, and supercapacitors. There are many traditional inorganic lithium storage materials, and they have been widely used. However, the inorganic lithium storage materials are limited by factors such as stoichiometric ratio, and the lithium storage capacity is limited; not only that, but the inorganic lithium storage materials themselves are brittle. The ...

AI Technical Summary

Problems solved by technology

However, so far, most organic lithium storage materials have shown low lithium storage capacity, poor high-rate charge-discharge performance and short cycle life. For example, pyrene-4,5,9,10 tetraketone has a specific capacity of only 275mAh / g. , and the capacity decreases to 120mAh / g after 20 cycles; naphthoquinone has a specific capacity of 190mAh / g, and the capacity retention rate after 100 cycles is less than 40%; anthraquinone has a specific capacity of 250mAh / g, and after 100 cycles Capacity decreased to 30mAh / g; 2-vinyl-4,8-dihydrobenzo-[1,2-b:4,5-b']-dithiophene-4,8-dione organic material has 225mAh / g of specific capacity, the capacity decreases to 50mAh / g after 25 cycles

The main reason for the poor cycle performance of the above-mentioned organic lithium storage materials is related to their solubility in organic carbonate solvents. The loss of active materials caused by dissolution is an important reason for the rapid decline of electrode capacity. Branches and other means increase the molecular weight of the material in order to reduce its solubility in organic solvents. However, the polymerization of small organic molecules will lead to the reduction or even disappearance of its active sites. decline

Not only that, due to the poor conductivity of organic lithium storage materials, the high-rate charge-discharge performance of the material is poor. The charge-discharge rate of many experimental studies can only be limited to between 0.1 and 1C, which is far from the requirements of industrial applications.

It can be seen that low lithium storage capacity, poor rate performance and cycle performance are the key and bottleneck restricting the further development and large-scale application of organic lithium storage materials.

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