A double-cathode structure and a lithium-oxygen battery made using it

A lithium-oxygen battery and dual-cathode technology, which is applied in structural parts, battery electrodes, fuel cell half-cells and secondary battery-type half-cells, can solve the problem of battery charging potential rise, battery cycle condition deterioration, positive electrode Limitation of electron transfer and other issues, to achieve the effects of reducing by-product formation, improving cycle life, and reducing charging potential

Active Publication Date: 2022-03-08
HENAN UNIVERSITY
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The fundamental reason is that during the operation of the battery, by-products and undecomposed Li 2 o 2 Continuous accumulation at the cathode creates a non-conductive passivation layer, resulting in limited electron transfer at the positive electrode
Liquid-phase catalyst molecules cannot be quickly regenerated, resulting in a continuous increase in the charging potential of the battery, further deteriorating the battery cycle condition

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
  • A double-cathode structure and a lithium-oxygen battery made using it
  • A double-cathode structure and a lithium-oxygen battery made using it
  • A double-cathode structure and a lithium-oxygen battery made using it

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0042] A method for assembling a lithium-oxygen battery with a double-cathode structure, the process is as follows:

[0043] (1) Preparation of electrolyte: LiTFSI, DBBQ, and TEMPO were dissolved in TEGDME to obtain electrolyte; the concentrations of LiTFSI, DBBQ, and TEMPO in TEGDME were 1 mol / L, 0.05 mol / L, and 0.2 mol / L, respectively;

[0044] (2) Preparation of inner cathode: cut the carbon film into a disc with a diameter of 1.6 cm, and then dry it in a vacuum oven at 80°C for 24 hours;

[0045] (3) Preparation of gas barrier layer: The polypropylene film was cut into discs with a diameter of 1.6 cm, and the porosity of the original barrier layer was 15% as measured by scanning electron microscopy; at the same time, for comparison, two other diameters of 1.6 cm polypropylene film discs, two discs were treated by plasma cleaning machine (power 11W) at room temperature for 5min and 10min respectively to obtain gas barrier layers with porosity of 50% and 80% respectively;

...

Embodiment 2

[0051] A method for assembling a lithium-air battery with a double-cathode structure, the process is as follows:

[0052] The difference from Example 1 is that the gas atmosphere in step (7) is air with a humidity of 25%. The battery fabrication process was as follows: the above single-cathode lithium-oxygen battery and double-cathode lithium-oxygen battery were assembled in an argon-filled glove box, packaged, and then the batteries were transferred to an air atmosphere with a humidity of 25%, left for four hours, and sealed. , and tested in a constant temperature oven at a temperature of 30 °C.

Embodiment 3

[0054] A preparation method of a conventional lithium-oxygen battery, the process is as follows:

[0055] The difference from Example 1 lies in step (1) preparation of electrolyte: LiTFSI is dissolved in TEGDME to obtain electrolyte; the concentration of LiTFSI is 1 mol / L.

[0056] The difference from Example 1 is that there is no PSS-Li / GO-Li / GF separator and no gas barrier layer in step (6). That is, the assembly sequence of a conventional lithium-oxygen battery is a lithium sheet, a glass fiber separator soaked in 90 μL of the above-mentioned LiTFSI electrolyte, an inner cathode, and an outer cathode.

[0057] To study the post-cycling discharge electrodes, the cells were disassembled in an Ar-filled glove box. The electrodes were carefully removed and immersed in ethylene glycol dimethyl ether (DME) for about 6 h. The impregnation process was then repeated several times to completely remove the electrolyte. After this, the electrodes were placed in a vacuum chamber and ...

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
water contentaaaaaaaaaa
water contentaaaaaaaaaa
Login to view more

Abstract

The invention discloses a double-cathode structure and a lithium-oxygen battery prepared by using the double-cathode structure. The double-cathode structure includes an inner layer cathode, a gas barrier layer and an outer layer cathode. The dual-cathode structure is used in lithium-oxygen batteries. The inner cathode provides a new electron transfer channel for the activation of liquid-phase catalysts, ensuring the continuous low charging voltage of the battery, thereby reducing the occurrence of side reactions. Li is blocked by a gas barrier layer 2 o 2 The deposition of the inner cathode ensures the effective electron transfer between the inner cathode and the liquid phase catalyst. The outer cathode has both electron transfer and Li storage 2 o 2 The role of discharge products. The lithium-oxygen battery with a double-cathode structure solves the problem that the liquid-phase catalyst cannot be activated due to the accumulation of by-products on the cathode of the traditional lithium-oxygen battery. It is a more advanced lithium-oxygen battery structure so far.

Description

technical field [0001] The invention belongs to the technical field of lithium-oxygen batteries, in particular to a double-cathode structure and a lithium-oxygen battery prepared by using the same. Background technique [0002] The theoretical energy density of aprotic lithium-oxygen battery is as high as 3500Wh kg -1 , which is an order of magnitude higher than the energy density of current commercial lithium-ion batteries, so it has broad application prospects in electric vehicles, portable power supplies and other fields. [0003] Due to the discharge product Li of the lithium-oxygen battery 2 O 2 The inherent low electronic conductivity of lithium-ion batteries and the presence of active intermediates in the cathode reaction process lead to limited electron transfer in the cathode reaction and a large number of side reactions, resulting in limited cycle life and specific capacity of the battery, which restricts the practical application of lithium-oxygen batteries. ...

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): H01M4/86H01M12/08
CPCH01M4/8605H01M4/8657H01M12/08H01M2004/8689Y02E60/10
Inventor 赵勇韩庆
Owner HENAN UNIVERSITY
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