Preparation and application of a special porous composite electrode for lithium-sulfur batteries

A composite electrode and lithium-sulfur battery technology, which is applied in the direction of battery electrodes, lithium batteries, negative electrodes, etc., can solve the problems that the product cannot be applied on a large scale, the proportion of effective materials in the electrode is reduced, and the battery cycle stability is poor, so as to achieve good electronic stability. The effect of transmission ability, simple and mature preparation process, and controllable pore size distribution

Active Publication Date: 2022-07-26
YANTAI UNIV
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] However, lithium-sulfur batteries are still in the laboratory stage, and the products of a few companies cannot be applied on a large scale.
The reason is mainly because lithium-sulfur batteries still have the following problems: 1) Electrochemical inertness, elemental sulfur and the final product Li 2 S / Li 2 S 2 Low conductivity hinders the reaction; 2) Shuttle effect, the intermediate product lithium polysulfide (Li polysulfide) in the reaction process 2 S n , 3≤n≤6) dissolved in the electrolyte, shuttling between positive and negative electrodes, resulting in active material loss and capacity decay; 3) volume expansion effect, due to sulfur (2.07g cm -3 ) and Li 2 S (1.66g cm -3 ) The large density difference makes the shrinkage and expansion of the volume occur during the charging and discharging process, and then destroys the electrode structure, resulting in poor cycle stability of the battery; 4) The dendrite powder of the lithium negative electrode, during the charging and discharging process, lithium will Uneven deposition on the negative electrode produces dendrites, which are easy to pierce the separator and cause safety problems. At the same time, lithium dendrites are easily corroded and pulverized by polysulfide ions, which consume a large amount of electrolyte and seriously affect the performance of the battery.
However, the traditional powder carbon materials need to add a binder, and need a dense aluminum film as a support. The effective substance (C / S composite) of the electrode is of small quality. Additional carbon powder acts as a conductive agent, further reducing the proportion of active substances in the electrode

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Preparation and application of a special porous composite electrode for lithium-sulfur batteries
  • Preparation and application of a special porous composite electrode for lithium-sulfur batteries
  • Preparation and application of a special porous composite electrode for lithium-sulfur batteries

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0033] 8 mmol ascorbic acid was added to 6 mL of water and stirred for 5 minutes to obtain a clear solution A. The Cu 2 Fe(CN) 6 ·10H 2 O (0.4 mmol) was added to 74 mL of ethylene glycol and stirred for 5 minutes to give B. Then, solution A was poured into solution B for an additional 15 minutes with magnetic stirring. The prepared clear yellow solution was transferred to a 100 mL polytetrafluoroethylene-lined autoclave and kept at 70° C. for 24 hours, then naturally cooled to room temperature, and centrifuged to obtain the compound. A self-supporting copper-based membrane was obtained after vacuum filtration. The copper-based film was cut and the metal lithium was melted onto the copper-based film to make a porous composite electrode.

Embodiment 2

[0035]Add 8 mmol of vitamin C to 6 mL of water and stir for 10 minutes to obtain a clear solution A. Add Cu2Fe(CN)6 10H2O (0.4 mmol) to 74 mL of ethylene glycol and stir for 5 minutes to obtain solution B, then, magnetically stir Pour solution A into solution B for an additional 15 minutes. The prepared transparent yellow solution was transferred to a 100 mL polytetrafluoroethylene-lined autoclave and kept at 50° C. for 24 hours, then naturally cooled to room temperature, and centrifuged to obtain the compound. A self-supporting copper-based membrane was obtained after vacuum filtration. The copper-based film is cut and the metal lithium is melted onto the copper-based film to make a porous composite electrode.

Embodiment 3

[0037] Add 8 mmol of vitamin C to 6 mL of water and stir for 5 minutes to obtain a clear solution A. The Cu 2 Fe(CN) 6 (0.4 mmol) was added to 74 mL of ethylene glycol and stirred for 5 minutes to give B. Then, solution A was poured into solution B for an additional 15 minutes with magnetic stirring. The prepared transparent yellow solution was transferred to a 100 mL polytetrafluoroethylene-lined autoclave and kept at 150° C. for 24 hours, then cooled to room temperature naturally, and centrifuged to obtain the compound. A self-supporting copper-based film was obtained after mechanical pressing. The copper-based membrane was cut out and the copper-based membrane was extruded onto the lithium sheet in a glove box.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
diameteraaaaaaaaaa
porosityaaaaaaaaaa
thicknessaaaaaaaaaa
Login to view more

Abstract

The invention discloses the preparation of a porous composite electrode for a lithium-sulfur battery and its application in the lithium-sulfur battery. A copper compound is used as a raw material, and a precursor solution is obtained by dissolving it in a solvent; the obtained precursor solution is spread on a non-woven fabric. Or on the glass plate substrate to obtain a precursor solution layer; compared with the conventional lithium negative electrode applied to lithium-sulfur batteries, the porous lithium negative electrode does not need to prepare slurry during the electrode preparation process, no need to scrape or press, which greatly shortens the time. The process flow of electrode preparation is improved, and the utilization rate of materials is increased. The porous lithium negative electrode is prepared by suction filtration and deposition, without adding a binder, and the porous lithium negative electrode is a whole, and there is no contact resistance between powder material particles. , Porous lithium negative electrode shows excellent ability to conduct electrons. From the perspective of reaction mechanism, lithiophilic copper-based film, porous lithium negative electrode has unparalleled performance in electrode preparation process, raw material utilization, conductivity, electrode composition and other aspects. Advantages and good application prospects.

Description

technical field [0001] The invention relates to the field of porous self-supporting composite electrodes for negative electrodes of lithium-sulfur batteries, in particular to the preparation and application of a special porous composite electrode for lithium-sulfur batteries. Background technique [0002] Among commercial secondary batteries, lithium-ion batteries are currently the secondary batteries with the highest energy density, but the theoretical specific capacity of lithium-ion batteries based on the "de-intercalation" theory is currently less than 300 mA h g -1 , the actual energy density is less than 200Whkg -1 , far from meeting people's demand for 500km battery life of electric vehicles. As a new electrochemical energy storage secondary battery, lithium-sulfur battery is different from traditional lithium-ion "de-intercalation" type materials. During the discharge process, sulfur and metal lithium undergo a two-electron reaction, which can release a high specifi...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): H01M4/134H01M4/62H01M4/1395H01M10/052
CPCH01M4/134H01M4/628H01M4/625H01M4/1395H01M10/052H01M2004/021H01M2004/027Y02E60/10
Inventor 王美日辛莎莎刘桃李婧崔洪涛刘媛媛
Owner YANTAI UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap