Unlock instant, AI-driven research and patent intelligence for your innovation.

A lithium metal battery negative electrode and its preparation method and a lithium metal battery

A lithium metal battery and negative electrode technology, applied in battery electrodes, electrode manufacturing, electrode current collector coating, etc., can solve the difficulties of large-scale commercial application of lithium metal secondary batteries, polarization, battery heat runaway, etc. question

Active Publication Date: 2021-09-24
CHONGQING UNIV
View PDF8 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0002] The uneven extraction and deposition of lithium on the surface of the lithium metal negative electrode during charge and discharge will form lithium dendrites. The existence of lithium dendrites leads to the following problems in lithium metal batteries: (1) Lithium dendrites that grow violently on the surface of the negative electrode are very likely Piercing the diaphragm to contact the positive electrode material of the battery, causing electronic contact between the positive and negative electrodes, forming a short circuit of the battery; this short circuit is often accompanied by a runaway battery heat, and will cause the flammable electrolyte to catch fire or even explode the battery; (2) Lithium sticks Crystal growth destroys the fragile solid electrolyte interface (SEI) film on the surface of the negative electrode, exposing more lithium to the electrolyte and forming a new SEI film; and the dendritic morphology of lithium dendrites makes the contact between lithium metal and electrolyte The sharp increase in the area intensifies the side reactions at the interface between lithium metal and the electrolyte. These side reactions irreversibly consume lithium metal and the electrolyte, but have no actual discharge capacity, resulting in a decrease in the Coulombic efficiency and capacity of the battery, which brings irreversible damage to the lithium metal anode. (3) The unstable interface between the lithium negative electrode and the electrolyte is repeatedly broken and rebuilt during the charging and discharging process, which can easily form "dead lithium", which will seriously hinder the transmission path of lithium ions and electrons in the negative electrode, thus Bring severe polarization and lower energy efficiency
[0003] The safety problems brought about by lithium dendrites make it difficult for lithium metal secondary batteries to achieve large-scale commercial applications

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 lithium metal battery negative electrode and its preparation method and a lithium metal battery
  • A lithium metal battery negative electrode and its preparation method and a lithium metal battery
  • A lithium metal battery negative electrode and its preparation method and a lithium metal battery

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0030] The invention provides a method for preparing a lithium metal battery negative electrode, comprising the following steps:

[0031] (1) Put Ti 3 C 2 Mix and react with lithium hydroxide aqueous solution to obtain LTO / Ti 3 C 2 composite materials;

[0032] (2) the LTO / Ti obtained in the step (1) 3 C 2 Composite material and polyvinylidene fluoride are mixed and ball milled to obtain mixed powder;

[0033] (3) mixing the mixed powder obtained in the step (2) with N-methylpyrrolidone to obtain a slurry;

[0034] (4) Coat the slurry obtained in the step (3) on the current collector, and then carry out vacuum drying treatment to obtain the LTO / Ti 3 C 2 cathode;

[0035] (5) With the lithium sheet as the anode, the LTO / Ti obtained in the step (4) 3 C 2 The cathode, lithium sheet and electrolyte are assembled into a button cell, and then the button cell is subjected to electrodeposition, and then the button cell is disassembled to obtain Li / LTO / Ti 3 C 2 negative el...

Embodiment 1

[0049] (1), LTO / Ti 3 C 2 Preparation of composite materials

[0050] Add 1 g of commercially available Ti to the Teflon beaker respectively 3 AlC 2 Powder, 40mL of commercially available hydrofluoric acid with a mass fraction of 40%, stirred and reacted at room temperature for 24h, then washed with ethanol and water by centrifugation, and dried to obtain Ti 3 C 2 ; put Ti 3 C 2 Added to a concentration of 1mol L -1 Lithium hydroxide aqueous solution, stirred and reacted at room temperature for 90h; then the reaction mixture was centrifuged and washed several times, and dried to obtain LTO / Ti 3 C 2 composite material.

[0051] (2), LTO / Ti 3 C 2 Preparation of cathode

[0052] With polyvinylidene fluoride and the LTO / Ti that make in the step (1) 3 C 2 The composite materials were mixed according to the mass ratio of 1:9, and then ball milled at 500rmp for 1h to obtain the mixed powder; using N-methylpyrrolidone as solvent, the mixed powder was prepared to a concent...

Embodiment 2

[0057] (1), LTO / Ti 3 C 2 Preparation of composite materials

[0058] Add 1 g of commercially available Ti to the Teflon beaker respectively 3 AlC 2 Powder, 40mL of commercially available hydrofluoric acid, stirred and reacted at room temperature for 24h, then washed with ethanol and water by centrifugation, and dried to obtain Ti 3 C 2 ; put Ti 3 C 2 Added to a concentration of 5mol L -1 Lithium hydroxide aqueous solution, stirred and reacted at room temperature for 500h; then the reaction mixture was centrifuged and washed several times, and dried to obtain LTO / Ti 3 C 2 composite material.

[0059] (2), LTO / Ti 3 C 2 Preparation of cathode

[0060] With polyvinylidene fluoride and the LTO / Ti that make in the step (1) 3 C 2 The composite materials were mixed according to the mass ratio of 1:7, and then ball milled under the condition of 800rmp for 0.5h to obtain the mixed powder; N-methylpyrrolidone was used as the solvent to prepare the mixed powder with a concen...

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
quality scoreaaaaaaaaaa
Login to View More

Abstract

The invention provides a lithium metal battery negative electrode, a preparation method thereof and a lithium metal battery, which belong to the field of lithium batteries. The preparation method of lithium metal battery negative electrode provided by the invention comprises the following steps: Ti 3 C 2 Mixed reaction with lithium hydroxide aqueous solution, in Ti 3 C 2 Lithium titanyl oxide LTO is generated on the surface, and LTO / Ti 3 C 2 Composite materials; LTO / Ti 3 C 2 The composite material and polyvinylidene fluoride are mixed and ball-milled to obtain mixed powder; the mixed powder is mixed with N-methylpyrrolidone to obtain a slurry; the slurry is coated on the current collector and vacuum-dried to obtain LTO / Ti 3 C 2 Cathode; with lithium sheet as anode, the LTO / Ti 3 C 2 The cathode, lithium sheet and electrolyte are assembled into a button cell, and then the button cell is subjected to electrodeposition, and then the button cell is disassembled to obtain Li / LTO / Ti 3 C 2 negative electrode. The negative electrode of the lithium metal battery provided by the invention has no lithium dendrite growth.

Description

technical field [0001] The invention relates to the field of lithium metal batteries, in particular to a lithium metal battery negative electrode, a preparation method thereof and a lithium metal battery. Background technique [0002] The uneven extraction and deposition of lithium on the surface of the lithium metal negative electrode during charge and discharge will form lithium dendrites. The existence of lithium dendrites leads to the following problems in lithium metal batteries: (1) Lithium dendrites that grow violently on the surface of the negative electrode are very likely Piercing the diaphragm to contact the positive electrode material of the battery, causing electronic contact between the positive and negative electrodes, forming a short circuit of the battery; this short circuit is often accompanied by a runaway battery heat, and will cause the flammable electrolyte to catch fire or even explode the battery; (2) Lithium sticks Crystal growth destroys the fragile...

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): H01M4/04H01M4/131H01M4/134H01M4/136H01M4/1391H01M4/1395H01M4/1397H01M4/36H01M4/38
CPCH01M4/0404H01M4/131H01M4/134H01M4/136H01M4/1391H01M4/1395H01M4/1397H01M4/362H01M4/382Y02E60/10
Inventor 魏子栋甘芮弋陈四国李存璞董琴付娜
Owner CHONGQING UNIV