Nonaqueous electrolyte secondary battery

A non-aqueous electrolyte and secondary battery technology, which is applied in the direction of non-aqueous electrolyte battery electrodes, secondary batteries, battery electrodes, etc., can solve the problems of self-discharge and side reactions easily, and achieve the effect of self-discharge inhibition

Active Publication Date: 2012-04-11
KK TOSHIBA
View PDF1 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Therefore, side reactions are prone to occur between the negative electrode active material and the non-aqueous electrolyte, thereby easily causing self-discharge

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
  • Nonaqueous electrolyte secondary battery
  • Nonaqueous electrolyte secondary battery
  • Nonaqueous electrolyte secondary battery

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0056]

[0057] First, lithium iron phosphate (LiFePO 4 ) powder 91% by weight, acetylene black 2.5% by weight, graphite 3% by weight, and polyvinylidene fluoride (PVdF) 3.5% by weight, were mixed to prepare a slurry. The slurry was coated on an aluminum foil (current collector) with a thickness of 15 μm, dried and then pressed to produce a 3 The positive electrode of the positive electrode layer.

[0058]

[0059] First, spinel lithium-titanium composite oxide (Li 4 Ti 5 o 12 ) powder 85% by weight, graphite 5% by weight, acetylene black 3% by weight, and PVdF 7% by weight, and these were mixed to prepare a slurry. The slurry was coated on an aluminum foil (collector) having a thickness of 11 μm, dried and pressed to produce a film having a density of 2.0 g / cm 3 The negative electrode of the negative electrode layer.

[0060]

[0061] The positive electrode, the separator made of a polyethylene porous film, the negative electrode, and the separator were stacked in...

Embodiment 2~10

[0072] A secondary battery similar to that of Example 1 was produced except that the aging treatment described in Table 1 was performed. XPS, AES, and photographs of the negative electrode were taken in the same manner as in Example 1. As a result, the same deposition form of metallic iron on the negative electrode as in Example 1 was confirmed. In addition, the results of the proportion of metallic iron covered on the surface of the negative electrode layer, the number of metallic iron non-covered regions, and the maximum height of the covered region calculated in Example 1 are also listed in Table 1.

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
Densityaaaaaaaaaa
Densityaaaaaaaaaa
Login to view more

Abstract

The invention relates to a nonaqueous electrolyte secondary battery comprising a negative electrode layer containing an active material (such as a titanium complex oxide) having a potential of not less than 0.5 V but not more than 2 V based on lithium metal at the time when lithium is inserted / removed. Since an SEI is rarely formed on the surface of a negative electrode which contains lithium-titanium complex oxide as a negative electrode active material, a side reaction is likely to occur between the negative electrode active material and the nonaqueous electrolyte solution, thereby easily causing self-discharge. Meanwhile, since 10-80% of each unit area of a negative electrode layer is composed of iron metal, the nonaqueous electrolyte secondary battery of the present invention is reduced in the area wherein the negative electrode layer surface and the nonaqueous electrolyte solution are in direct contact with each other. As a result, self-discharge is significantly suppressed, while maintaining discharge characteristics and high-rate charging performance with a large current.

Description

technical field [0001] The present invention provides a nonaqueous electrolyte secondary battery. Background technique [0002] In a non-aqueous electrolyte secondary battery, an organic covering film called SEI (Solid Electrolyte Interface, also known as a solid electrolyte interface film) is formed on the surface of the negative electrode containing graphite as the negative electrode active material. Therefore, the organic covering film can prevent direct contact between the non-aqueous electrolyte and the negative electrode active material. As a result, continuous reaction of the negative electrode active material and the nonaqueous electrolyte can be suppressed. [0003] On the other hand, an anode containing a lithium-titanium composite oxide as an anode active material hardly forms SEI on its surface. That is, the negative electrode active material is always in direct contact with the nonaqueous electrolyte. Therefore, side reactions easily occur between the negativ...

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
IPC IPC(8): H01M4/02H01M4/48H01M10/40H01M4/131H01M4/485H01M10/0525H01M10/0566
CPCH01M2004/027Y02E60/122H01M4/485H01M4/13H01M10/0525H01M2004/021H01M4/134H01M4/131H01M4/362Y02E60/10
Inventor 松野真辅稻垣浩贵高见则雄
Owner KK TOSHIBA
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