Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

A lithium-ion battery with a mixed negative electrode and its formation method

A technology of lithium-ion battery and formation method, which is applied in the field of lithium-ion battery and its formation, can solve the problems that the advantages of mixed negative electrode cannot be fully utilized, the working voltage of lithium titanate battery is low, and lithium-ion battery is difficult to apply, so as to prevent electrolysis Excessive liquid loss, tight fit, and the effect of taking into account the characteristics of use

Active Publication Date: 2022-05-06
HEFEI GUOXUAN HIGH TECH POWER ENERGY
View PDF10 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the high lithium intercalation potential of the lithium titanate negative electrode also causes the low working voltage and low energy density of the lithium titanate battery.
The lithium-ion battery made of graphite and lithium titanate mixed negative electrode has both the advantages of both, but it is different from a single negative electrode material in that there are two charging and discharging platforms during the charge and discharge process. For lithium-ion batteries composed of mixed negative electrodes, one working platform is about 3.65V, and the other platform is about 2.2V. The usual method of composition and capacity is difficult to apply to lithium-ion batteries composed of mixed negative electrodes, and cannot give full play to the advantages of mixed negative electrodes, resulting in Degradation of battery performance

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

[0031] A ternary battery with a capacity of 6Ah, the positive electrode is nickel-cobalt lithium manganese oxide, the negative electrode is a mixed negative electrode of graphite and lithium titanate, electrolyte and lithium salt, the electrolyte includes ethylene carbonate and dimethyl carbonate, and the lithium salt is lithium hexafluorophosphate . The mixing ratio of negative electrode graphite and lithium titanate is 90 / 10.

[0032] (1) First charge the battery to 1.5V with a constant current of 0.01C;

[0033] (2) Adjust the current and charge it to 2.2V with a constant current of 0.02C, and charge it at a constant voltage of 2.2V until the cut-off current is 0.03C;

[0034] (3) The negative pressure of the battery is pumped for 0.5h, which is the same as the negative pressure pumping in the prior art, and turned into a negative pressure of -40kPa, and then left to stand for 4h;

[0035] (4) Adjust the current and charge it to 3.0V with a constant current of 0.03C;

[...

Embodiment 2

[0045] A ternary battery with a capacity of 6Ah, the positive electrode is nickel-cobalt lithium manganese oxide, the negative electrode is a mixed negative electrode of graphite and lithium titanate, electrolyte and lithium salt, the electrolyte includes ethylene carbonate and dimethyl carbonate, and the lithium salt is lithium hexafluorophosphate . The mixing ratio of negative electrode graphite and lithium titanate is 80 / 20.

[0046] (1) First charge the battery to 1.5V with a constant current of 0.02C;

[0047] (2) Adjust the current and charge it to 2.2V with a constant current of 0.03C, and charge it at a constant voltage of 2.2V until the cut-off current is 0.05C;

[0048] (3) The negative pressure of the battery is pumped for 1 hour, turned into a negative pressure of -40kPa, and then left to stand for 4 hours;

[0049] (4) Adjust the current and charge it to 3.0V with a constant current of 0.04C;

[0050] (5) Adjust the current and charge it to 3.5V with a constant...

Embodiment 3

[0059] A ternary battery with a capacity of 6Ah, the positive electrode is nickel-cobalt lithium manganese oxide, the negative electrode is a mixed negative electrode of graphite and lithium titanate, electrolyte and lithium salt, the electrolyte includes ethylene carbonate and dimethyl carbonate, and the lithium salt is lithium hexafluorophosphate . The mixing ratio of negative electrode graphite and lithium titanate is 70 / 30.

[0060] (1) First charge the battery to 1.5V with a constant current of 0.01C;

[0061] (2) Adjust the current and charge it to 2.2V with a constant current of 0.03C, and charge it at a constant voltage of 2.2V until the cut-off current is 0.05C;

[0062] (3) Pump the negative pressure of the battery for 0.5h, turn it into a negative pressure of -40kPa, and then let it stand for 4h;

[0063] (4) Adjust the current and charge it to 3.0V with a constant current of 0.05C;

[0064] (5) Adjust the current and charge it to 3.5V with a constant current of 0....

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

No PUM Login to View More

Abstract

The invention discloses a lithium ion battery with a mixed negative electrode and a composition and capacity method thereof. The negative electrode of the lithium ion battery is made by mixing graphite and lithium carbonate. Lithium-ion batteries made of graphite and lithium carbonate mixed negative electrodes have both the advantages of both, but unlike a single negative electrode material, there are two charging and discharging platforms during the charge and discharge process. Lithium-ion batteries composed of negative electrodes are difficult to apply, and the advantages of mixed negative electrodes cannot be fully utilized. The present invention provides a lithium-ion battery composition and capacity method for mixed negative electrodes, which adopts a step-by-step chemical formation method, taking into account the characteristics of the two materials of the mixed negative electrode , can form a stable SEI film on the surface of the graphite negative electrode while taking into account the high lithium intercalation potential of lithium carbonate, thereby improving the capacity and cycle characteristics of the battery.

Description

technical field [0001] The invention relates to the technical field of lithium batteries, in particular to a lithium ion battery with a mixed negative electrode and a formation method thereof. Background technique [0002] At present, the commercialized lithium-ion negative electrodes are mainly graphite and lithium titanate. Graphite will form an SEI film on the surface when it is charged and discharged for the first time, resulting in irreversible capacity loss, and because the lithium intercalation potential is close to that of metal lithium, low temperature and overcharge are easy. The formation of lithium dendrites raises safety concerns. Compared with graphite negative electrode, lithium titanate has higher lithium intercalation potential, higher safety, excellent low temperature performance, cycle stability and fast charging ability. However, the high lithium intercalation potential of the lithium titanate negative electrode also results in low operating voltage and ...

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): H01M4/485H01M4/583H01M4/131H01M4/133H01M10/0525H01M10/058
CPCH01M4/485H01M4/583H01M4/133H01M4/131H01M10/0525H01M10/058Y02E60/10Y02P70/50
Inventor 刘春丽吴诺刘京生
Owner HEFEI GUOXUAN HIGH TECH POWER ENERGY
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products