Gel electrolyte precursor and chemical battery

#The present invention relates to a gel electrolyte precursor, a chemical battery comprising a gel electrolyte obtained from the gel electrolyte precursor, and a method of manufacturing the chemical battery.

#A nonaqueous electrolyte secondary battery, which is an example of the chemical battery, comprises an electrode group including a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode, and a nonaqueous electrolyte held by the electrode group. Used as the positive electrode active material is, for example, a lithium-containing complex oxide. Also, the negative electrode is formed of, for example, lithium, a lithium alloy, or a carbonaceous material absorbing-desorbing lithium. On the other hand, a liquid nonaqueous electrolyte prepared by dissolving a lithium salt as an electrolyte in a nonaqueous solvent such as propylene carbonate or γ-butyrolactone is used as the nonaqueous electrolyte.

#In recent years, it is required to increase the capacity of the battery, to make the battery thinner and to increase the active area of the battery in accordance with miniaturization, reduction in thickness and improvement in the performance of electronic appliances. It is proposed to use a film material such as a laminate film in place of a metal can as a vessel for housing the electrode group in an attempt to decrease the thickness of the nonaqueous electrolyte secondary battery and to make the secondary battery light in weight. In the case of using a film material, however, the liquid nonaqueous electrolyte tends to leak to the outside. Also, the distribution of the nonaqueous electrolyte within the electrode group tends to be nonuniform. As a result, a problem is generated that the cycle characteristics are lowered. In order to avoid the particular problem, it is studied to impart viscosity to the liquid nonaqueous electrolyte so as to lower the fluidity of the liquid nonaqueous electrolyte.

#The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate presently preferred embodiments of the invention, and together with the general description given above and the detailed description of the preferred embodiments given below, serve to explain the principles of the invention.

#FIG. 1 is a partial cross sectional view showing a cylindrical nonaqueous electrolyte secondary battery as an example of a chemical battery of the present invention;

#FIG. 2 is a cross sectional view showing a thin type nonaqueous electrolyte secondary battery as another example of the chemical battery of the present invention; and

#A first gel electrolyte precursor and a second gel electrolyte precursor of the present invention will now be described.

#1. First Gel Electrolyte Precursor:

#The first gel electrolyte precursor of the present invention comprises a gelling agent and an electrolyte, said gelling agent containing at least one kind of an epoxy resin selected from the group consisting of an epoxy compound having an alicyclic structure and at least one epoxy group (epoxy ring) represented by chemical formula (1) given below and an alicyclic epoxy resin: