Lithium secondary cell and its nonaqueous electrolyte

A lithium secondary battery, non-aqueous electrolyte technology, applied in the direction of secondary batteries, non-aqueous electrolyte storage batteries, battery electrodes, etc., can solve problems such as unprocessed cycle characteristics

Inactive Publication Date: 2006-09-20
UBE IND LTD
View PDF6 Cites 10 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, substantive studies such as cycle

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

[0062] [Preparation of non-aqueous electrolyte]

[0063] Prepare a non-aqueous solvent of propylene carbonate (PC): dimethyl carbonate (DMC) (capacity ratio) = 1:2, and dissolve LiPF as an electrolyte salt in it 6 , And make it to a concentration of 1M to prepare a non-aqueous electrolyte, and then add dimethyl oxalate to 0.5% by weight relative to the non-aqueous electrolyte, add vinylene carbonate (VC) and make it It reaches 2% by weight.

[0064] [Production of lithium secondary battery and measurement of battery characteristics]

[0065] LiCoO 2 (Positive electrode active material), acetylene black (conductive agent), and polyvinylidene fluoride (binder) are mixed in the proportions of 90% by weight, 5% by weight and 5% by weight, respectively, and 1-methyl-2 is added to it -Pyrrolidone solvent and mixing, coating the obtained mixture on aluminum foil, drying, pressure molding, and heat treatment to make a positive electrode. Will have the interplanar spacing (d 002 ) Is 0.335...

Embodiment 2

[0068] As additives, with respect to the non-aqueous electrolyte, except that 1% by weight of dimethyl oxalate and 2% by weight of vinylene carbonate were used, a non-aqueous electrolyte was prepared in the same manner as in Example 1, and an 18650 battery was produced. The battery characteristics after 200 cycles were measured, and the discharge capacity retention rate was 85.7%. Table 1 shows the manufacturing conditions and battery characteristics of the 18650 battery.

Embodiment 3

[0070] As additives, a non-aqueous electrolyte was prepared in the same manner as in Example 1 except that 2% by weight of dimethyl oxalate and 2% by weight of vinylene carbonate were used with respect to the non-aqueous electrolyte to produce an 18650 battery. The battery characteristics after 200 cycles were measured, and the discharge capacity retention rate was 86.1%. Table 1 shows the manufacturing conditions and battery characteristics of the 18650 battery.

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
Face distanceaaaaaaaaaa
Thicknessaaaaaaaaaa
Densityaaaaaaaaaa
Login to view more

Abstract

A lithium secondary cell exhibiting excellent long term cell characteristics such as cycle characteristics, electric capacity and storage characteristics, and a nonaqueous electrolyte usable in such a lithium secondary cell. The lithium secondary cell comprising a positive electrode, a negative electrode, and a nonaqueous electrolyte produced by dissolving an electrolytic salt into a nonaqueous solvent is characterized in that the positive electrode is a material containing a lithium composite oxide, the negative electrode is a material containing graphite, and the nonaqueous electrolyte contains a dialkyl oxalate, and a vinylene carbonate and/or 1,3-propane sultone.

Description

Technical field [0001] The present invention relates to a lithium secondary battery excellent in battery characteristics such as long-term cycle characteristics, electric capacity, and storage characteristics of the battery, and a non-aqueous electrolyte that can be used in the lithium secondary battery. Background technique [0002] In recent years, lithium secondary batteries have been widely used as power sources for driving small electronic devices and the like. Lithium secondary battery is mainly composed of positive electrode, non-aqueous electrolyte and negative electrode, especially LiCoO 2 Lithium secondary batteries such as lithium composite oxides as the positive electrode and carbon materials or lithium metal as the negative electrode are suitably used. As the non-aqueous electrolyte for the lithium secondary battery, carbonates such as ethylene carbonate (EC) and propylene carbonate (PC) are very suitably used. [0003] However, with regard to battery characteristics...

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): H01M10/40H01M4/58H01M4/02H01M4/587H01M10/0525H01M10/0567H01M10/0569
CPCY02E60/122H01M10/052Y02E60/10
Inventor 安部浩司三好和弘桑田孝明松森保男
Owner UBE IND LTD
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