Negative electrode of rechargeable battery

A technology for rechargeable batteries and negative electrodes, applied to battery electrodes, non-aqueous electrolyte battery electrodes, negative electrodes, etc., which can solve the problems of reduced inhibition

Inactive Publication Date: 2003-03-05
NEC CORP
View PDF0 Cites 22 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In other words, due to the occlusion and release of lithium ions, the volume of the lithium or lithium alloy layer changes significantly, while the volume of the lithium halide layer remains unchanged, and the internal stress damages part of the lithium halide film, thus causing dendrites. Inhibition of compound formation is reduced

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
  • Negative electrode of rechargeable battery
  • Negative electrode of rechargeable battery
  • Negative electrode of rechargeable battery

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0045] Several examples and comparative examples of the negative electrode of the present invention are now described. However, these examples do not limit the present invention. Example 1 Preparation of negative electrode

[0046] Such as figure 1 As shown, a 10 μm thick electrolytic copper foil is used as the current collector 1a. The slurry is applied to the copper foil 1a, and then dried and pressed to form the first layer 2a. The slurry is prepared by mixing graphite with polyvinylidene fluoride, and then dissolving the mixture in N-methyl-2-pyrrolidone solvent. The second layer 3a and the third layer 4a are formed by vacuum evaporation deposition of lithium-silicon alloy and lithium fluoride (LiF), respectively. The equipment used for vacuum evaporation deposition of lithium-silicon alloy or LiF has a vacuum degree of 10 -6 to 10 -5 Pa, roll width 60mm, heated by electron beam or electric resistance. The capacity of the negative electrode thus formed is the sum ...

example 10

[0053] Manufacture negative electrode by the same condition as example 1, just with the LiN(C of 1M 2 f 2 SO 2 ) 2 Dissolve the electrolyte that ethylene carbonate and diethyl carbonate make to replace the electrolyte of example 1, and the material of the second layer 3a and the 3rd layer 4a is polycrystalline Li-Si alloy and LiF respectively, and these materials are obtained by adding N- (C 2 f 5 SO 2 ) 2 Introduced by reaction with lithium. The negative electrode and battery of Example 10 were evaluated as in Example 1, and the results are listed in Table 1.

[0054] As in Examples 2-9, compared with Comparative Examples 1-5, the initial charge and discharge efficiency and capacity retention rate or cycle characteristics of the battery of Example 10 were improved.

[0055] However, the initial charge and discharge efficiency and capacity retention ratio of Example 10 were lower than those of Example 1 using the amorphous Li-Si alloy. The charge and discharge reactio...

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
retention rateaaaaaaaaaa
Login to view more

Abstract

A negative electrode for a rechargeable battery includes: a current collector, a first layer containing a conductive material to occlude and release lithium ion, the first layer formed on the current collector, a second layer containing a metal selected from lithium and lithium alloy, the second layer formed on the first layer, and a third layer containing a lithium ion. conductive material, the third layer formed on the second layer. The third layer prevents the lithium and / or the lithium alloy in the second layer from being in contact with the electrolyte and smoothly feeds the lithium to the second layer to improve the efficiency of the negative electrode. The first layer can occlude and release the part of the lithium to be occluded and released, thereby reducing the volume change of the second layer. Such a structure of the negative electrode enables us to enhance cycling efficiency, and to attain long cycle life and good safety.

Description

technical field [0001] The invention relates to a negative electrode of a rechargeable battery (secondary battery) containing lithium metal or lithium alloy as an active material. Background technique [0002] Rechargeable batteries using lithium metal and lithium alloys as negative electrodes show superior energy densities compared to lithium-ion rechargeable batteries using graphite negative electrodes. However, when the negative electrode contains lithium metal as the active material, some drawbacks regarding cycle efficiency and safety must be overcome. Due to the strong chemical activity of lithium, part of the lithium deposited on the negative electrode will lose its activity during charging, thus forming various lithium compounds on the surface of the electrode, such as lithium hydroxide, lithium oxide, and lithium carbonate. The resulting film is then made up of a variety of products. This uneven film causes lithium to be locally deposited on the surface of the neg...

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 Applications(China)
IPC IPC(8): H01M10/05H01M4/133H01M4/134H01M4/137H01M4/1393H01M4/1395H01M4/36H01M4/60H01M4/62
CPCH01M2004/027H01M4/602Y02E60/122H01M4/587H01M4/13H01M4/366H01M4/04Y02E60/10H01M4/133H01M4/137H01M4/64
Inventor 森满博山本博规宇津木功二入山次郎三浦环宫地麻里子
Owner NEC CORP
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