Surface-alloyed metal lithium foil and preparation method thereof, metal lithium negative electrode and lithium battery

A technology of surface alloying and metal lithium, applied in the field of electrochemical energy storage, can solve the problems of active lithium consumption, dendrite melting, loss of electrochemical activity, etc., and achieve the effect of good cycle performance

Inactive Publication Date: 2021-11-02
CHINA ENERGY LITHIUM
View PDF5 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, during the use of metal lithium as the negative electrode of lithium secondary batteries, during the charging process, lithium dendrites will be formed on the surface of the negative electrode of lithium-ion batteries due to uneven deposition. Lithium dendrites may pierce the diaphragm, causing a short circuit in the battery and causing the battery to explode. Safety accidents occur; dendrites will melt during the discharge process, forming "dead lithium" and losing electrochemical activity. If things go on like this, a large amount of active lithium will be consumed, and the battery cycle performance will decline

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0030] Example 1 - Pressure Compounding

[0031] Stack the 2-micron aluminum foil and the 50-micron lithium foil neatly, place them on a flat press, adjust the pressure to 20MPa, and hold for 120s. Take out the laminated pole piece and find that the aluminum foil layer disappears, indicating that the surface alloying reaction is complete.

[0032] Cut this pole piece into a pole piece with a width of 45 mm and a length of 58 mm as the negative electrode (A).

[0033] The positive electrode uses lithium cobaltate, and the binder polyvinylidene fluoride (PVDF), the conductive agent acetylene black (AB), is dispersed in N-methylpyrrolidone (NMP) according to the mass ratio of 90:5:5, stirred evenly, and coated with Cover it on aluminum foil, dry it, and use it as the positive electrode (B).

[0034] Stack A, diaphragm, and B in sequence, encapsulate them in aluminum-plastic film, inject electrolyte (1M lithium hexafluorophosphate (LiFP6), ethylene carbonate (EC): dimethyl carbon...

Embodiment 2

[0036] Example 2 - Solution Reactive Alloying

[0037] Prepare reaction solution (C): 1 g of tin chloride is dissolved in 50 g of tetrahydrofuran.

[0038] Soak a 30 μm lithium piece with a diameter of 16 mm in C for 30 s. The metal lithium (D) alloyed on the surface is obtained as the negative electrode.

[0039] The positive electrode uses elemental sulfur, and the binder PVDF and conductive agent AB are dispersed into NMP according to the mass ratio of 70:10:20, stirred evenly, coated on aluminum foil, dried, and used as the positive electrode (E).

[0040] Place D, diaphragm, and E in the button battery case in turn, and inject electrolyte (1M lithium bistrifluoromethanesulfonylimide (LiTFSI), 1,3-dioxolane (DOL): ethylene glycol Dimethyl ether (DME), 0.2wt% lithium nitrate (LiNO 3 )) to form a battery.

[0041] The battery is activated at 0.05C, and then cycled at 0.3C. After 1000 cycles, the capacity retention rate is still 80%. After disassembling the battery, it w...

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
Login to view more

Abstract

The invention provides surface-alloyed metal lithium foil and a preparation method thereof, a metal lithium negative electrode and a lithium battery. The surface-alloyed metal lithium foil comprises: a metal lithium foil bulk phase; and an alloying layer which is positioned on at least one surface of the metal lithium foil bulk phase, wherein the alloying layer is formed in situ through alloying reaction of metal lithium on the surface. The alloying layer and the metal lithium are integrated and can change along with the volume change of the metal lithium negative electrode, and the alloy layer and the metal lithium bulk phase cannot be separated, so that the lithium battery has better cycle performance.

Description

technical field [0001] The invention relates to the technical field of electrochemical energy storage, in particular to a metal lithium negative electrode material for a lithium battery and a preparation method and application thereof. Background technique [0002] Due to its high energy density, lithium batteries have been widely used in portable electronic devices, grid energy storage, electric mobility and other fields. However, after decades of development of commercial lithium-ion batteries with graphite as the negative electrode, the energy density has reached its bottleneck, making it difficult to meet the requirements for energy density and battery life in the application field. Therefore, it is necessary to develop new anode materials to improve the energy density of batteries. [0003] Lithium metal has a specific capacity of 3.86Ah / g, a potential of -3.04V relative to the hydrogen standard electrode, and a density of 0.534g / cm 3 , is recognized by the industry a...

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): H01M4/36H01M4/38H01M4/40H01M4/134H01M10/0525
CPCH01M4/366H01M4/382H01M4/405H01M4/134H01M10/0525H01M2004/027Y02E60/10
Inventor 王亚龙刘承浩陈强牟翰波郇庆娜
Owner CHINA ENERGY LITHIUM
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