Rechargeable battery with nonaqueous electrolyte and process for producing negative electrode

A non-aqueous electrolyte and secondary battery technology, applied in the direction of non-aqueous electrolyte batteries, secondary batteries, battery electrodes, etc., can solve the problems of capacity reduction, Si cracking and micronization, and achieve high energy density and excellent cycle life Effect

Inactive Publication Date: 2008-01-16
PANASONIC CORP
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] However, Si is prone to fracture and micronization due to the volume change involved in absorbing and desorbing Li
Therefore, after charge / discharge cycles, the capacity is greatly reduced, and it is difficult to use Si as the negative electrode active material

Method used

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  • Rechargeable battery with nonaqueous electrolyte and process for producing negative electrode

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0110] In this example, the negative electrode active material obtained from the above powder mixture (1) was used, and the average particle diameter was examined. The weight ratio of the Si phase which is the A phase in the negative electrode active material was 30% by weight. The negative electrode active material was prepared by mechanical alloying method, and the measurement of its particle size distribution showed a wide particle size range of 0.5-200 μm and an average particle size (D50) of 50 μm. The negative electrode active material was adjusted to have the particle size distribution shown in Table 1 by classifying the negative electrode active material with a sieve. Then, a negative electrode sheet was molded using the negative electrode active material having each particle size distribution, and battery evaluation was performed using the negative electrode sheet. The negative electrode active materials of Batteries 1-8 were not classified with a sieve. Table 1 sho...

Embodiment 2

[0116] In this example, the negative electrode active material obtained from the above powder mixtures (2)-(5) was used. The weight ratio of the Si phase as the A phase in the negative electrode active material was 30% by weight. In Example 2, as shown in Table 3, as the kind of transition metal contained in the second phase (B phase) in the negative electrode active material, the cases of Ti, Zr, Ni, Cu and Fe were examined. Transition metals Co and Mn were also examined as comparative examples.

[0117] The preparation method of the negative electrode active material is as described above. The weight ratio of the Si phase as the A phase in the negative electrode active material was 30% by weight. The average particle diameters (D50) obtained after sieving were 1.0 μm, respectively, as shown in Table 2.

[0118] Each anode active material is the same as the above-mentioned materials except for using a different transition metal. However, all negative electrode sheets were...

Embodiment 3

[0125] This example examines a method of wet-milling an anode active material prepared by a mechanical alloying method using balls as a medium when the transition metal contained in phase B is Ti.

[0126] Zirconia balls with a diameter of 5 mm were used as the balls (medium). A 500ml polyethylene container was used as the container. 120 ml of n-butyl acetate was used as a dispersion medium. The rotation frequency of the ball mill was 120 rpm. Then, the negative active material was collected by removing the dispersion medium. The adjustment of the predetermined particle diameter is performed by adjusting the milling time.

[0127] The synthesis method of the negative electrode active material, and the preparation and evaluation methods of the battery are the same as in the above examples.

[0128] Table 3 shows the material yield when the particle size was adjusted by the wet milling of this example. In addition, for comparison, the material yield at the time of sieving i...

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Abstract

An image heating apparatus of electromagnetic induction heating-type capable of providing a proper relative heat-generation distance with a magnetic flux generation member even when the magnetic flux generation member is bent by its own weight or thermally deformed includes at least an exciting coil, a holder for holding the exciting coil, and a rotatable fixation roller for generating heat by magnetic flux from the exciting coil to heat a material to be heated. The holder has an outer diameter phid 1 at a central portion and an outer diameter phid 2 at an end portion in a longitudinal direction of the holder perpendicular to a conveyance direction of the material to be heated. The outer diameters phid 1 and phid 2 satisfies: phid 1 <phid 2.

Description

technical field [0001] The present invention relates to a nonaqueous electrolyte secondary battery. More specifically, the present invention relates to a nonaqueous electrolyte secondary battery having an improved negative electrode, having a high energy density, and being excellent in long-term cycle characteristics. Background technique [0002] Since nonaqueous electrolyte batteries have high energy density and can reduce the size and weight of devices, there are increasing demands for their use as main power sources of various electronic devices and as storage backup power sources. Currently, with the remarkable progress of portable electronic devices, there is a strong demand for further miniaturization, higher performance and maintenance-free, higher energy density for non-aqueous electrolyte batteries. [0003] Since battery characteristics are highly dependent on the characteristics of the cathode active material and the anode active material, many studies have been...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): H01M4/38H01M4/04H01M4/02H01M10/40H01M4/134H01M4/1395H01M10/0525H01M10/36
CPCY02E60/122H01M10/0525H01M4/1395H01M4/38H01M2004/021H01M4/134H01M4/386Y02E60/10H01M4/139H01M10/052
Inventor 植田智博佐野阳子南野哲郎稻富友山本辉明美藤靖彦
Owner PANASONIC CORP
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