Lithium-supplementing current collector, preparation method and application thereof, negative pole piece and lithium ion battery

A technology for lithium-ion batteries and negative pole pieces, applied in battery electrodes, secondary batteries, electrode carriers/collectors, etc., can solve the problems of reduced compaction density, increased impedance, and more lithiation, so as to prevent lithium precipitation , reduce internal resistance, accelerate the effect of conduction

Inactive Publication Date: 2020-07-17
TIANJIN ENERGIES
View PDF10 Cites 16 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Due to the presence of Li on the surface of lithium metal powder 2 CO 3 The cladding layer needs to be activated by rolling to activate the Li 2 CO 3 The cladding layer is crushed to release the internal Li, but by this method, after the lithium powder dissolves, a lot of holes will be left inside the pole piece, or the surface of the pole piece will become uneven, which not only reduces the compaction density, The conduction of electrons at the negative electrode will also be greatly affected (increased impedance), and at the same time, there is likely to be uneven mixing of the slurry, resulting in excessive local lithiation, poor uniformity of lithium supplementation, and difficult control of the process, making the actual effect difficult to meet the design requirements.

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
  • Lithium-supplementing current collector, preparation method and application thereof, negative pole piece and lithium ion battery
  • Lithium-supplementing current collector, preparation method and application thereof, negative pole piece and lithium ion battery
  • Lithium-supplementing current collector, preparation method and application thereof, negative pole piece and lithium ion battery

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0047] The above-mentioned lithium-supplementing current collector can be used in the preparation of lithium-ion batteries, and is especially suitable for negative electrodes in lithium-ion batteries. When the above-mentioned lithium-supplementing current collector is used in the preparation of lithium-ion batteries, the positive and negative electrodes can be prepared first, and then pre-conditioned. Specifically:

[0048] Negative electrode sheet preparation: Negative electrode slurry is obtained by mixing the negative electrode active material, conductive agent, binder and additives uniformly, and the negative electrode slurry is respectively coated on the lithium-replenishing current collector (that is, the porous carbon-coated current collector containing lithium-replenishing material) above, drying at 80-120°C, and rolling after drying to obtain rolled negative electrode sheets. Wherein, the mass ratio of the negative electrode active material, conductive agent, and bin...

Embodiment 1

[0053] (1) The body of the current collector is prepared (that is, the preparation of the porous carbon-coated current collector), 90wt% conductive carbon black, 5wt% SBR (styrene-butadiene rubber) and 5wt% CMC (carboxymethyl cellulose sodium) are mixed uniformly (need Illustrate that the consumption of conductive carbon black, SBR and CMC is the mass percent with reference to the total weight of the conductive paste, and the following examples are all the same) to obtain the conductive paste; the prepared conductive paste coating Dry at 90°C on the upper and lower surfaces of the copper foil current collector. After drying, use a punching device to create evenly distributed circular through holes on the carbon-coated copper foil current collector with a porosity of 20%. The schematic diagram of the current collector body is shown in figure 2 and image 3 As shown, the current collector body includes a base layer 102 copper foil with a thickness of 10 μm, a first carbon-coat...

Embodiment 2

[0060] (1) The body of the current collector is prepared (that is, the preparation of the porous carbon-coated current collector). Mix 90wt% conductive carbon black, 5wt% SBR (styrene-butadiene rubber) and 5wt% CMC (carboxymethyl cellulose sodium) to conduct electricity Slurry: Coat the prepared conductive paste on the upper and lower surfaces of the copper foil current collector, and dry it at 90°C. After drying, use a punching device to create evenly distributed Circular through hole with 20% porosity. The current collector body includes a base layer copper foil with a thickness of 10 μm, a first carbon-coated layer and a second carbon-coated layer respectively located on the upper surface and the lower surface of the base layer, both with a thickness of 3 μm, and located on the current collector body (also That is, the through holes on the carbon-coated current collector), the diameter of the through holes is 0.2 μm.

[0061] (2) Negative active material (a mixture of grap...

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
thicknessaaaaaaaaaa
pore sizeaaaaaaaaaa
thicknessaaaaaaaaaa
Login to view more

Abstract

The invention provides a lithium-supplementing current collector, a preparation method and application thereof, a negative pole piece and a lithium ion battery. The lithium-supplementing current collector comprises a current collector body and a lithium-supplementing material layer. The current collector body comprises a first carbon-coated layer, a substrate layer and a second carbon-coated layerwhich are arranged in sequence, wherein two adjacent layers of the first carbon-coated layer, the substrate layer and the second carbon-coated layer are tightly attached and fixedly connected; a plurality of through holes are formed in the first carbon-coated layer at intervals and penetrate through the substrate layer and the second carbon-coated layer; and the plurality of through holes are filled with the lithium supplementing material layer. According to the lithium-supplementing current collector disclosed by the invention, the current collector contains a lithium supplementing substance, so that accurate lithium supplementing of a silicon-carbon negative electrode can be realized, the internal resistance of the pole piece after lithium supplementing is reduced, and the rate capability and the cycle performance of a battery are improved.

Description

technical field [0001] The invention belongs to the field of lithium-ion batteries, and in particular relates to a lithium-supplementing current collector, a preparation method, an application thereof, a negative pole piece and a lithium-ion battery. Background technique [0002] The development of new energy vehicles is widely regarded as an important strategic measure to effectively address energy and environmental challenges. In addition, for our country, the development of new energy vehicles is the only way for our country to move from a "big auto country" to a "powerful auto country". Electric vehicles with power batteries as part or all of their power are currently the main direction of development of new energy vehicles due to their significant advantages of high efficiency, energy saving and off-site emissions. In order to solve the problem of "mileage anxiety" of pure electric vehicles, the battery The development of new energy storage material systems with higher...

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): H01M4/66H01M10/0525
CPCH01M4/661H01M4/663H01M4/667H01M10/0525Y02E60/10
Inventor 张进高秀玲从长杰王驰伟
Owner TIANJIN ENERGIES
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