JP2002298792A - Battery device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize an electric device for supplying battery voltage. SOLUTION: A flat winding electrode body 25 having a positive electrode 21 and a negative electrode 22 is accommodated in an armor can 32 having an appearance of a rectangle wherein widths of side surfaces 30A and 30B adjacently provided are different. A non-aqueous electrolyte as a medium of ionic conduction between the positive electrode 21 and the negative electrode 22 is injected through an injection hole 44 which is provided on an outer peripheral part of the wider side surface 30A which is deformed to expand so that a central part rises highest in an ordinary using condition. The injection hole 44 is sealed by a sealing member 41. Thus, the sealing member 41 is disposed on the wider side surface 30A of the armor can 32 so that the sealing member 41 is prevented from projecting outward than the rising of the central part. It is possible to provide a space for accommodating the battery in the electric device for supplying battery voltage in accordance with a shape of the armor can 32. Thus, the electric device for supplying battery voltage can be miniaturized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery device, and is suitably applied to, for example, a non-aqueous electrolyte secondary battery.

[0002]

2. Description of the Related Art Conventionally, in a non-aqueous electrolyte secondary battery,
A lithium composite oxide such as a lithium-cobalt composite oxide is used as a positive electrode active material, and a lithium ion-doped and undoped substance such as lithium, a lithium ion alloy, and a carbon material are used as a negative electrode active material. Is used.

[0003] A non-aqueous electrolyte secondary battery functions as a battery by reacting the positive electrode active material and the negative electrode active material, and can provide a relatively high battery voltage and a relatively high energy density. In recent years, by having many advantages such as having excellent charge and discharge cycle characteristics,
Widely used.

By the way, as a non-aqueous electrolyte secondary battery,
There is a flat rectangular shape configured as shown in FIG.

As shown in FIG. 9, in a flat non-aqueous electrolyte secondary battery (hereinafter referred to as a non-aqueous electrolyte square secondary battery) 1, a strip-shaped positive electrode and a strip-shaped A flat wound electrode body (hereinafter, referred to as a flat wound electrode body) 2 which is formed by winding the negative electrode in a state of being insulated through two strip-shaped separators. are doing.

[0006] In this non-aqueous electrolyte square secondary battery 1, a bottomed square cylindrical negative electrode can 3 having different widths between adjacent side surfaces, and a can lid fitted into the opening of the negative electrode can 3 4
The flat wound electrode body 2 is accommodated in a flat rectangular outer can 5 composed of: and a nonaqueous electrolyte (not shown) serving as a medium for ion conduction between the positive electrode and the negative electrode is filled. Is impregnated in the separator.

In the non-aqueous electrolyte secondary battery 1, a positive electrode lead (not shown) welded to the positive electrode of the flat wound electrode body 2 inside the outer can 5 is formed in a ring shape on the can lid 4. A negative electrode lead (not shown) that is welded to the positive electrode pin 7 provided via a gasket 6 made of an insulating material and that is welded to the negative electrode of the flat wound electrode body 2 has a predetermined position on the inner surface of the negative electrode can 3. Welded to.

As a result, in the non-aqueous electrolyte square secondary battery 1, the battery voltage generated by the discharge reaction of the positive electrode and the negative electrode (that is, the positive electrode active material and the negative electrode active material) inside the outer can 5 is changed to the positive electrode pin 7 and Output can be made to the outside via the negative electrode can 3.

[0009]

However, in the non-aqueous electrolyte square secondary battery 1 having such a structure, FIGS.
As shown in FIG. 5, a can lid 4 is provided with a nonaqueous electrolyte injection hole 4A.

In this non-aqueous electrolyte square secondary battery 1, after the non-aqueous electrolyte is injected into the exterior can 5 through the injection hole 4A of the can lid 4, the spherical metal member 11 is subjected to resistance. The rivet-shaped sealing member 12 is formed so as to be pressed against the injection hole 4A while being heated by a welding method, and the exterior can 5 is sealed by welding the sealing member 12 to the injection hole 4A.

However, this non-aqueous electrolyte square secondary battery 1
In, for example, the battery voltage is supplied by being stored in a battery storage space of a portable electronic device that tends to be smaller, and when the outer can 5 is reduced in size according to the electronic device for supplying the battery voltage, Since it is difficult to secure a space for disposing the sealing member 12 together with the gasket 6 and the positive electrode pin 7 on the can lid 4, the sealing member 12 can be disposed on the negative electrode can 3 side instead of the can lid 4. It is considered.

For this reason, as shown in FIG. 11 where parts corresponding to those in FIG.
5, the injection hole is formed in the narrow side surface 17A of the relatively wide side surface and the narrower side surface (hereinafter referred to as the narrow side surface) 17A of the negative electrode can 17 instead of the can lid 16. A method has been proposed in which a sealing member 12 is formed in the injection hole 17B by a resistance welding method.

However, according to this method, the sealing member 1 is removed from the can lid 16 in the non-aqueous electrolyte square secondary battery 15.
Although the entire outer can 18 can be reduced in size by removing the outer can 2, the outer can 18 can be used in an electronic device for supplying battery voltage because the sealing member 12 protrudes from the narrow side surface 17A of the negative electrode can 17.
It is necessary to secure a battery storage space larger than the size of the electronic device, and there is a problem that miniaturization of electronic devices is hindered.

In order to solve this problem, as shown in FIG. 12 in which the same reference numerals are given to the corresponding parts in FIG. 11, a concave portion is formed in the opening of the injection hole 17C formed in the narrow side surface 17A of the negative electrode can 17. 17D, and the sealing member 1 is formed in the recess 17D.
There is a method of welding such that the second head 12A is housed.

However, according to this method, the outer can 18
The non-aqueous electrolyte to be injected into the inside of the opening 17C easily accumulates in the recess 17D at the opening of the injection hole 17C, and the non-aqueous electrolyte accumulated in the recess 17D is not easily wiped off. When welding is performed by the method, a spark is generated by the non-aqueous electrolyte in the concave portion 17D between the sealing member 12 and the injection hole 17C to form a gap.
In some cases, it is not enough to solve such a problem.

The present invention has been made in view of the above points, and it is an object of the present invention to propose a battery device capable of reducing the size of an electronic device for supplying a battery voltage.

[0017]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, according to the present invention, an electrode body having a positive electrode and a negative electrode is housed in an outer can having a rectangular appearance in which adjacent side surfaces have different widths. It becomes a medium for ion conduction between the positive electrode and the negative electrode through an injection hole formed in the outer peripheral portion of the wide side surface which expands and deforms so that the central portion expands and deforms to the maximum in the normal use state of the side surfaces to be used. The electrolyte was injected, and the injection hole was sealed with a sealing member.

Accordingly, the sealing member can be arranged on the wide side surface of the outer can in such a manner as to prevent the outer portion from protruding outside the bulge at the center thereof. As a result, the sealing member can be provided in an electronic device for supplying battery voltage. A battery storage space that matches the shape of the outer can can be provided.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

In FIG. 1, reference numeral 20 denotes a non-aqueous electrolyte square secondary battery according to the present invention as a whole, and a positive electrode active material layer is formed on both surfaces of a positive electrode current collector made of strip-shaped aluminum foil or the like. The formed positive electrode 21 and the negative electrode 22 in which a negative electrode active material layer is formed in a film shape on both surfaces of a negative electrode current collector made of a strip-shaped copper foil or the like are formed of a strip-shaped microporous polypropylene film. Two first and second separators 23 and 2
A flat wound electrode body (hereinafter, referred to as a flat wound electrode body) 25 formed so as to be wound while being insulated from each other with the intermediary 4 interposed therebetween.

In this case, the non-aqueous electrolyte square secondary battery 20
Is a bottomed square cylindrical negative electrode can 30 having different widths between adjacent side surfaces, and a can lid 31 fitted into an opening of the negative electrode can 30.
The flat wound electrode body 25 is housed inside a flat rectangular outer can 32 composed of: and a nonaqueous electrolyte (not shown) serving as a medium for ion conduction between the positive electrode 21 and the negative electrode 22 is filled. And the two separators 23 and 24 are impregnated.

The non-aqueous electrolyte square secondary battery 20
As shown in FIGS. 2A to 2C, a positive electrode lead 33 welded to the positive electrode 21 of the flat wound electrode body 25 is provided on the can lid 31 via a gasket 34 made of a ring-shaped insulating material. By welding to the provided positive electrode pin 35, the positive electrode 21 and the positive electrode pin 35 are electrically and mechanically connected via the positive electrode lead 33.

The nonaqueous electrolyte square secondary battery 20 has a negative electrode lead 36, which is welded to the negative electrode 22 of the flat wound electrode body 25, welded to a predetermined portion on the inner surface of the negative electrode can 30. The negative electrode 22 and the negative electrode can 30 are electrically and mechanically connected via a negative electrode lead 36.

Thus, the nonaqueous electrolyte square secondary battery 20
Can output a battery voltage generated by a discharge reaction of the positive electrode 21 and the negative electrode 22 (that is, the positive electrode active material and the negative electrode active material) inside the outer can 32 through the positive electrode pin 35 and the negative electrode can 30. Has been made.

Here, in the non-aqueous electrolyte square secondary battery 20, the negative electrode can 30 having all the flat sides is used at the time of manufacture, but as shown in FIG. When the stored flat wound electrode body 25 is charged to be in a normal use state, the cathode 21 and the negative electrode 22 of the flat wound electrode body 25 are expanded by charging, and a relatively wide pair of the negative electrode can 30 is formed. Aspects (hereinafter,
The pair of wide side surfaces 30A of the pair of side surfaces 30A, which are referred to as a wide side surface) 30A and a pair of side surfaces narrower than this (hereinafter, referred to as a narrow side surface) 30B, are arranged from substantially the center of each side. The center portion of the 30A is expanded and deformed so that the center portion rises most.

In the negative electrode can 30, the wide side surface 30
A narrow side surface 30B and a can lid 31 and a narrow side surface 30B and a bottom surface 30C are integrated on two orthogonal sides of each of the four corners of A so as to be orthogonal to each other. The amount of deformation at the four corners in the wide side surface 30A is relatively small by being regulated by the side surface 30B and the can lid 31 and the narrow side surface 30B and the bottom surface 30C.

The non-aqueous electrolyte square secondary battery 20
As shown in FIGS. 4A and 4B, a battery housing having a rectangular cross section provided in the electronic device for supplying battery voltage in consideration of deformation of the wide side surface 30A of the negative electrode can 30 in a normal use state. It is stored in the space 40 and used.

Therefore, the nonaqueous electrolyte square secondary battery 20
As is clear from FIGS. 1 to 3, for injecting a non-aqueous electrolyte into, for example, the upper right corner of the four corners having a relatively small deformation in the wide side surface 30 </ b> A of the negative electrode can 30 in the normal use state. An injection hole (not shown) is provided.

In this case, the wide side surface 3
The sealing member 41 is welded to the injection hole drilled at the upper right corner of 0A in the manufacturing process of the non-aqueous electrolyte square secondary battery 20 according to the following procedure shown in FIGS. ing.

That is, as shown in FIG. 5A, when the outer can 32 containing the flat spirally wound electrode body 25 (FIG. 1) is formed, the wide side surface 3 is formed with respect to the negative electrode can 30 of the outer can 32.
The leading end of the electrolyte solution injection nozzle 45 is brought into contact with the opening end of the injection hole 44 pre-drilled at 0A, and in this state, non-water supplied from the electrolyte solution supply device (not shown) via the electrolyte solution injection nozzle 45. The electrolyte is injected into the outer can 32 through the injection hole 44.

Next, as shown in FIG. 5 (B), a strip-shaped electrolyte wiping cloth 48 running from the delivery reel 46 to the take-up reel 47 is rotated by a rotatable pressing roller 49 into the injection hole of the negative electrode can 30. The non-aqueous electrolyte leaking into the opening of the injection hole 44 is wiped by running the electrolyte wiping cloth 48 by the delivery reel 46 and the take-up reel 47 while pressing the non-aqueous electrolyte while pressing the opening 44.

Subsequently, as shown in FIG. 5C, a metal member 50 made of, for example, a spherical stainless alloy is placed on the opening of the injection hole 44 of the negative electrode can 30 so as to close the opening.
As shown in FIG. 5 (D), the metal member 50 is pressed into the injection hole 44 while being heated by a resistance welding method to form the metal member 50 into a rivet-shaped sealing member 41, and the foot portion 41A is formed. The outer can 32 is sealed by being inserted into the injection hole 44 and pressing the lower surface of the head around the opening end of the injection hole 44, thus welding the sealing member 41 so as to close the injection hole 44.

Thus, the non-aqueous electrolyte square secondary battery 2
0 is the center of the sealing member 41 that is most prominent in the wide side surface 30A by welding the sealing member 41 to the injection hole 44 formed in the upper right corner where the amount of change is relatively small within the wide side surface 30A. It is configured to be able to prevent it from protruding outside the part.

Therefore, the non-aqueous electrolyte square secondary battery 20
4A and 4B, although the sealing member 41 is welded to the wide side surface 30A of the negative electrode can 31 in place of the can lid 31, the electronic device for supplying the battery voltage is used. A battery storage space that matches the shape of the outer can 32 can be provided without being affected by the sealing member 41.

By the way, as shown in FIG. 6 (A), A is substantially parallel to the width direction of the wide side surface 30A shown in FIG.
A negative electrode can 30 in a normal use state along the dotted line of -A '
Has a gentle slope such that the central portion rises most from one side (hereinafter referred to as a vertical side), which is a boundary portion with the narrow side surface 30B, to the central portion. It becomes an arc shape.

Therefore, in order to select the position of the injection hole 44 on the wide side surface 30A of the negative electrode can 30, it is necessary to select the position shown in FIG.
As shown in the figure, the deformed shape of the surface from the vertical side along the width direction to the central portion of the wide side surface 30A is represented by a first right triangle S1 having the base of the original plane for convenience, and the wide side surface The welding position of the sealing member 41 at 30A is based on the original plane as the base and the first right triangle S
It is represented as a second right triangle S2 similar to 1.

The width of the wide side surface 30A is W and the distance from the vertical side to the center of the widest portion is W / 2, and the height from the original plane of the wide side surface 30A to the center of the highest portion is H. I do.

Further, the distance from the vertical side to the center of the upper surface of the head of the sealing member 41 is x, the thickness of the head of the sealing member 41 is h, and the distance from the original flat surface of the wide side surface 30A is sealed. Formula (1) where H 'is the height of the head of the stop member 41 to the center of the lower surface.

[0039]

(Equation 1)

As described above, the distance x from the vertical side to the center of the upper surface of the head of the sealing member 41, the height H 'from the original plane of the wide side surface 30A to the center of the lower surface of the head of the sealing member 41, and , The distance W / 2 from the vertical side to the center of the wide side surface 30A and the height H from the original plane of the wide side surface 30A to the center.

Here, if this equation (1) is developed, the height H 'from the original plane of the wide side surface 30A to the center of the lower surface of the head of the sealing member 41 in the normal use state is expressed by the following equation (2).

[0042]

(Equation 2)

In order to actually provide the sealing member 41 on the surface of the wide side surface 30A, the value obtained by adding the height H 'and the thickness h of the head of the sealing member 41 is expressed by ( 3)
formula

[0044]

(Equation 3)

The height H of the wide side surface 30A from the original plane to the center of the wide side surface 30A is set within the range.

Then, this equation (3) is developed for a distance x from the vertical side of the wide side surface 30A to the center of the upper surface of the head of the sealing member 41, whereby the equation (4) is obtained.

[0047]

(Equation 4)

As shown in the following expression, a position where the sealing member 41 can be welded between the vertical side of the wide side surface 30A and the center without protruding outside the center of the wide side 30A (that is, the position of the wide side 30A). The distance x) from the vertical side is specified.

Thus, the non-aqueous electrolyte square secondary battery 2
At 0, the position of the injection hole 44 in the width direction can be selected in accordance with the welding position of the sealing member 41 specified in the width direction of the negative electrode can 30.

In addition, the cross-sectional shape obtained by breaking the vicinity of the vertical side of the negative electrode can 30 in the normal use state along the dotted line BB 'almost parallel to the vertical direction of the wide side surface 30A shown in FIG. , The wide side surface 30 described above with reference to FIG.
A shape having a gentle slope such that the central portion rises most from one side (hereinafter, referred to as a horizontal side), which is a boundary portion between the opening end and the bottom surface, to the central portion in substantially the same manner as the cross-sectional shape in the width direction of A. It becomes an arc shape.

Therefore, the non-aqueous electrolyte square secondary battery 20
In FIGS. 6A and 6B, the positions at which the sealing member 41 can be welded to the longitudinal direction of the wide side surface 30A without protruding outward from the central portion are defined by the expressions (1) to (4). In the same manner as described above, the injection hole 4 in the longitudinal direction of the wide side surface 30A is specified in accordance with the specified welding position.
4 is selected.

Thus, in the non-aqueous electrolyte square secondary battery 20, the four corners of the wide side surface 30A do not protrude from the center of the maximum width, but protrude from the center of the maximum height in the width direction. The welding position of the sealing member 41 that satisfies the conditions in these two directions, which does not occur, can be specified accurately, and thus the nonaqueous electrolyte injection hole 44 is drilled in accordance with the welding position thus specified. The installation position can be easily selected.

In the case of this embodiment, in the non-aqueous electrolyte rectangular battery 20, the negative electrode can
0 wide side surface 30A (one surface) is deformed so that the center thereof rises about 0.2 to 0.7 [mm], and the thickness of the head of the sealing member 41 welded to the wide side surface 30A Is selected to be 0.05 to 0.2 [mm].

The non-aqueous electrolyte square secondary battery 20
In, the welding position of the sealing member 41 is specified by actually using such numerical values, and the drilling position of the injection hole 44 is selected in accordance with the specified welding position.

In the case of this embodiment, in the non-aqueous electrolyte square secondary battery 20, the can lid 31 is provided with the positive electrode pin 35 made of an aluminum alloy, and is formed in the shape of a square cylinder with a bottom by iron. A negative electrode can 30 formed by plating nickel on the surface of the member is used.

Furthermore, in the case of this embodiment, in the nonaqueous electrolyte secondary battery 20, when forming the positive electrode 21, a layered compound using a transition metal containing an alkali metal as the positive electrode active material, Chalcogen compounds such as spinel compounds (particularly oxides of alkali metals and transition metals) are used.

As such a chalcogen compound, a composite oxide generally represented by AxM'M "O2 can also be used, where A is lithium (Li), sodium (N
a) and one kind of element selected from potassium (K), and x is a number from 0.5 to 1.1 (0.5 ≦ x ≦ 1.1).

The first element represented by M 'is iron (Fe), cobalt (Co), nickel (Ni), manganese (Mn), copper (Cu), zinc (Zn), chromium (C
r), vanadium (V), and at least one element from the group consisting of titanium (Ti). The second element represented by M ″ is iron (Fe), cobalt (Co). ), Manganese (Mn), copper (Cu), zinc (Z
n), aluminum (Al), tin (Sn), boron (B), gallium (Ga), chromium (Cr), vanadium (V), titanium (Ti), magnesium (Mg), calcium (Ca), strontium ( It contains at least one element from the group of elements consisting of Sr).

On the other hand, when the negative electrode 22 is formed, a lithium alloy, a lithium alloy compound, or the like is used as a negative electrode active material that can be doped and dedoped with lithium.

Incidentally, the lithium alloy compound is, for example, a compound represented by the chemical formula of DsEtLiu, D represents at least one of a metal element and a semiconductor element capable of forming an alloy or a compound with lithium, and E represents It represents at least one of metal elements and semiconductor elements other than lithium and D. s is a number greater than 0 (0 <
s) and t are numbers of 0 or more (0 ≦ t), and u is a number of 0 or more (0 ≦ t).

The metal or semiconductor element capable of forming an alloy or compound with lithium is preferably a Group 4B metal element or semiconductor element, particularly preferably silicon (Si) or tin (Sn). Preferred is silicon (Si).

The metal element or semiconductor element capable of forming an alloy or compound with lithium includes magnesium (Mg), boron (B), aluminum (Al), gallium (Ga), indium (In), and silicon (S).
i), germanium (Ge), tin (Sn), palladium (Pb), antimony (Sb), bismuth (Bi),
Each metal element of cadmium (Cd), silver (Ag), zinc (Zn), hafnium (Hf), zirconium (Zr), yttrium (Y) and alloy compounds thereof (for example, L
i-Al or Li-Al-M1 (M1 is 2A, 3B, 4B
Consisting of one or more of transition metal elements), AlSb,
In this embodiment, elements such as boron (B), silicon (Si), and arsenic (As), which are semiconductor elements, are included in the metal element.

As such an alloy compound, preferably, M2xSi (M2 is one or more metal elements except silicon (Si), and x is a number larger than 0 (0
<X)) and M3xSn (M3 is one or more metal elements except tin (Sn), and x is a number greater than 0 (0 <x)). Specifically, SiB4, SiB
6, Mg2Si, Mg2Sn, Ni2Si, TiSi
2, MoSi2, CoSi2, NiSi2, CaSi
2, CrSi2, Cu5Si, FeSi2, MnSi
2, NbSi2, TaSi2, VSi2, WSi2, Z
nSi2 and the like.

In addition, as the negative electrode active material capable of doping and undoping lithium, a carbon material, a metal oxide, a polymer material, and the like can be used. As the carbon material, hardly graphitizable carbon is used. , Artificial graphite, cokes, graphites, glassy carbons, fired organic polymer compounds, carbon fibers, activated carbon, carbon blacks and the like. Among them, cokes include pitch coke, needle coke, petroleum coke, etc., and the organic polymer compound fired body is obtained by firing a polymer material such as phenols and furans at an appropriate temperature and carbonizing. Things. In addition, as the metal oxide, iron oxide, ruthenium oxide, molybdenum oxide,
There are tin oxide and the like, and as the polymer material, there are polyacetylene, polypyrrole and the like.

In the above configuration, in the non-aqueous electrolyte square secondary battery 20, the flat wound electrode body 2 inside the outer can 32 is provided.
5 is charged and brought into a normal use state, the positive electrode 21 and the negative electrode 22 of the flat wound electrode body 25 expand due to expansion.
The pair of wide side surfaces 30A are expanded and deformed so that the center portions of the wide side surfaces 30A rise from the substantially central portion of each side to the central portion of the wide side surface 30A.

Therefore, the non-aqueous electrolyte secondary battery 2
In the case of No. 0, the nonaqueous electrolyte injection hole 44 is formed in a corner portion (that is, an upper right corner) where the amount of deformation is relatively small on the wide side surface 30A by utilizing the deformation of the wide side surface 30A of the negative electrode can 30. Then, the sealing member 41 was welded to the injection hole 44 to seal the outer can 32.

Therefore, the non-aqueous electrolyte square secondary battery 20
In this configuration, the sealing member 41 can be disposed on the wide side surface 30A of the negative electrode can 30 so as not to protrude outside the bulge at the center thereof. As a result, the sealing member 41 is sealed in the battery voltage supply electronic device. It is possible to provide a battery storage space that matches the shape of the outer can 32 in a normal use state without considering the arrangement position of the member 41 at all.

Further, in the non-aqueous electrolyte square secondary battery 20, as described above with reference to FIGS. 6A and 6B and the equations (1) to (4), the negative electrode can 3 in the normal use state is used.
The head 41B of the sealing member 41 is not embedded in the wide side surface 30 in order to select the position of the injection hole 44 in consideration of the deformation of the shape of the wide side surface 30A in the width direction and the vertical direction of the wide side 30A. It can be arranged properly so as not to protrude outside the wide side surface 30A.

As a result, in the non-aqueous electrolyte square secondary battery 20, even if the sealing member 41 is disposed on the wide side surface 30 A of the negative electrode can 30 instead of the can lid 31,
0 is almost certainly prevented from becoming larger than the outer can 32 by the sealing member 41, and the size can be easily reduced.

Incidentally, the non-aqueous electrolyte square secondary battery 20
In this case, unlike the case described above with reference to FIG. 12, since a concave portion is not formed at the opening end of the injection hole 44 formed in the wide side surface 30 </ b> A of the negative electrode can 30, the nonaqueous electrolytic solution is injected into the exterior can 32. The non-aqueous electrolyte leaking around the opening end of the injection hole 44 can be wiped off accurately, and the outer can 32 can be almost securely sealed by the sealing member 41 welded to the injection hole 44. Can be.

According to the above-described structure, the nonaqueous electrolyte injection hole 44 is formed at the corner of the pair of wide side surfaces 30A, which are expanded and deformed in the normal use state, at a relatively small amount of deformation. Since the sealing member 41 is welded to the injection hole 44, the sealing member 41 is connected to the wide side surface 3 of the negative electrode can 30.
0A is disposed so as to prevent it from protruding outside the bulge at the center thereof, and a battery accommodating space adapted to the shape of the outer can 32 can be provided in the battery voltage supply electronic device. A nonaqueous electrolyte square secondary battery capable of reducing the size of a supply electronic device can be realized.

In the above-described embodiment, the rivet-shaped sealing member 41 is formed by applying pressure while heating the spherical metal member 50 by the resistance welding method, and is welded to the injection hole 44. I mentioned the case,
The present invention is not limited to this. The sealing member is welded to the injection hole by using a laser welding method, a plasma welding method and a resistance welding method alone or in combination, or as shown in FIGS. 7 (A) to 7 (D). A columnar sealing member 60, a columnar sealing member 61 whose peripheral side surface is tapered in advance, and a columnar foot 62A
A sealing member 62 having various shapes such as a rivet-shaped sealing member 62 having a rivet-shaped sealing member 63 having a foot portion 63A whose peripheral side surface is tapered in advance is press-fitted into the injection hole. Even in this case, the outer can can be properly sealed.

Further, in the above-described embodiment, the case where the sealing member 41 is arranged at the upper right corner of the wide side surface 30A of the negative electrode can 30 has been described. If the member 41 does not protrude outside the center of the wide side surface 30A, the lower right corner, the upper left corner, and the lower left corner of which the deformation amount is smaller than the center portion of the wide side surface 30A that is most prominent, and the center of the vertical side and the horizontal side. As such, it can be arranged at various positions along the outer periphery.

Further, in the above-described embodiment,
A negative electrode can 30 formed by plating nickel on the surface of a non-aqueous electrolyte prismatic secondary battery 20 formed in iron into a square cylinder with a bottom and a positive electrode pin 35 made of an aluminum alloy
Although the case where the can lid 31 provided with is used has been described, the present invention is not limited to this, and as shown in FIGS. 8A to 8C, the non-aqueous electrolyte square secondary battery 70 To
A positive electrode can 71 having a bottomed rectangular tube shape made of an aluminum alloy and a can lid 73 having a negative electrode pin 72 formed by plating nickel on the surface of a bar-shaped member made of iron are used. In such a case, the positive electrode lead 74 may be welded to a predetermined portion on the inner surface of the positive electrode can 71, and the negative electrode lead 75 may be welded to the negative electrode pin 72 of the can lid 73.

Further, in the above-described embodiment,
The case where the present invention is applied to the non-aqueous electrolyte square secondary batteries 20 and 70 described above with reference to FIGS. 1 to 8C has been described. However, the present invention is not limited to this, and the square As long as at least one pair of wide side surfaces of the outer can is deformed so as to expand and an electrolyte is injected into the outer can and sealed, such as a nickel hydrogen secondary battery, etc. It can be widely applied to various battery devices.

Further, in the above-described embodiment,
As an electrode body having a positive electrode and a negative electrode, a strip-shaped positive electrode 21
Also, a case has been described in which the flat wound electrode body 25 formed by winding the strip-shaped negative electrode 22 in an insulated state with the two strip-shaped separators interposed therebetween is used. However, the present invention is not limited to this, as long as it has a positive electrode and a negative electrode, such as a laminated electrode body formed by laminating a sheet-like positive electrode and a sheet-like negative electrode while sequentially insulating them through a sheet-like separator. In addition, various other electrode bodies can be widely applied.

Further, in the above-described embodiment,
Although the case where a non-aqueous electrolyte is applied as an electrolyte serving as a medium for ion conduction between the positive electrode and the negative electrode of the electrode body has been described, the present invention is not limited to this, and the ion between the positive electrode and the negative electrode of the electrode body is not limited thereto. As a conductive medium, non-aqueous solvents, solid electrolytes, polymer electrolytes, non-aqueous electrolytes such as solid or gel electrolytes formed by mixing and dissolving an electrolyte in a polymer compound, and other various electrolytes Can be widely applied.

Incidentally, non-aqueous solvents include ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, γ-butyl lactone, γ
Cyclic ester compounds such as valerolactone, diethoxyethane, tetrahydrofuran, 2-methyltetrahydrofuran, ether compounds such as 1,3-dioxane, methyl acetate, chain ester compounds such as methyl propylene acid, dimethyl carbonate, diethyl carbonate, Chain carbonates such as ethyl methyl carbonate, 2,4
-Difluoroanisole, 2,6-difluoroanisole, 4-bromoveratrol and the like can be used alone or as a mixed solution of two or more.

In the gel electrolyte, polyacrylonitrile and a copolymer of polyacrylonitrile can be used as a polymer material. Incidentally, the copolymerized monomers (vinyl monomers) include vinyl acetate, methyl methacrylate, butyl methacrylate, methyl acrylate, butyl acrylate, itaconic acid, methyl hydride hydride, ethyl acrylate, acrylamide, vinyl chloride, There are vinylidene fluoride, vinylidene chloride and the like.

In addition to this, acrylonitrile butadiene rubber, acrylonitrile butadiene styrene resin, acrylonitrile chloride polyethylene propylene diene styrene resin, acrylonitrile vinyl chloride resin, acrylonitrile methacrylate resin, acrylonitrile acrylate resin Etc. can also be used.

Further, as the gel electrolyte, polyethylene oxide and a copolymer of polyethylene oxide can be used as a polymer material. Examples of the copolymerizable monomer include polypropylene oxide, methyl methacrylate, butyl methacrylate, and acrylic acid. Methyl acrylate and butyl acrylate.

Further, polyvinylidene fluoride and a copolymer of polyvinylidene fluoride may be used as the polymer material in the gel electrolyte, and hexafluoropropylene, tetrafluoroethylene, etc. may be used as the copolymerization monomer. is there. As described above, various polymer materials can be used for the gel electrolyte, and these polymer materials can be used alone or in combination of two or more.

In order to form a gel electrolyte layer, a cyclic ester compound such as ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, γ-butyl lactone, γ-valerolactone, or diethoxy is used as a non-aqueous solvent. Ether compounds such as ethane, tetrahydrofuran, 2-methyltetrahydrofuran and 1,3-dioxane; chain ester compounds such as methyl acetate and methyl propylene acid; chain carbonates such as dimethyl carbonate, diethyl carbonate and ethyl methyl carbonate; -Difluoroanisole, 2,6-difluoroanisole, 4-bromoveratrol and the like are used alone or as a mixed solution of two or more.

In the gel electrolyte layer, when polyvinylidene fluoride is used as the gel electrolyte,
It is preferable to use a gel electrolyte made of a multicomponent polymer obtained by copolymerizing polyhexafluoropropylene, polytetrafluoroethylene, or the like. More preferably,
By using a gel electrolyte made of a copolymer of polyvinylidene fluoride and polyhexafluoropropylene, a gel electrolyte having higher mechanical strength can be obtained.

The electrolyte salts used in the non-aqueous electrolyte include lithium hexafluorophosphate (LiPF6), lithium hexafluoroarsenate (LiAsF6), lithium tetrafluoroborate (LiBF4), and lithium perhydrochloride (LiBF4). LiClO
4), lithium trifluoromethylsulfonate (LiCF
3SO3), lithium trifluoromethanesulfoxide-nitride lithium (LiN (CF3SO3) 2),
Lithium nonafluorobutanesulfonate (LiC4F9S
Lithium salts such as O3) can be used alone or in combination of two or more. The molar amount of the electrolyte salt in the non-aqueous electrolyte in the gel electrolyte is 0.8 to 2.0 [mol / mol] so that good ionic conductivity can be obtained.
l].

Further, in the above-described embodiment,
Adjacent side faces have a rectangular appearance with different widths, accommodate the electrode body, are injected with electrolyte, and expand and deform so that the center of the adjacent side faces expands most in the normal use state. As the outer can having an injection hole for injecting an electrolyte into the outer peripheral portion of the wide side surface, a bottomed square cylindrical negative electrode can 30 having a different width between adjacent side surfaces as described above with reference to FIGS. A flat rectangular outer can 32 comprising a can lid 31 fitted into the opening of the negative electrode can 30
However, the present invention is not limited to this, and has a rectangular appearance in which the widths of adjacent side surfaces are different from each other, and the electrolyte is injected while accommodating the electrode body,
If an injection hole for injecting the electrolyte can be formed in the outer peripheral portion of the wide side surface which expands and deforms so that the center portion expands to the maximum in the normal use state of the adjacent side surfaces, it is simply adjacent. Various other outer cans can be widely applied, such as a rectangular outer can having different widths between the side surfaces.

Further, in the above-described embodiment,
As a sealing member for sealing the injection hole of the outer can, FIG.
As described above with respect to (D), the case where the sealing member 41 formed by forming the metal member 50 made of a spherical stainless steel alloy into a rivet shape is described.
The present invention is not limited to this, but may be made of various other materials as long as the injection hole of the outer can can be sealed, and the sealing members 60 to 6 of various shapes described above with reference to FIGS. 7A to 7D.
As shown in FIG. 3, various other sealing members can be widely applied.

[0088]

As described above, according to the present invention, an electrode body having a positive electrode and a negative electrode is housed in an outer can having a rectangular appearance in which the widths of adjacent side surfaces are different from each other. Injection of an electrolyte serving as a medium for ion conduction between the positive electrode and the negative electrode through an injection hole formed in the outer peripheral portion of a wide side surface which expands and deforms so that the center portion expands and deforms most in a normal use state, Since the injection hole is sealed by the sealing member, the sealing member is disposed on the wide side surface of the outer can in such a manner as to prevent the outer can from protruding outside the bulge at the center thereof, and the battery voltage is reduced. The supply electronic device can be provided with a battery storage space according to the shape of the outer can, and thus the battery voltage supply electronic device can be downsized.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing an embodiment of a configuration of a non-aqueous electrolyte square secondary battery according to the present invention, with a part thereof broken away.

FIG. 2 is a schematic top view, a schematic cross-sectional view, and a schematic side view partially cut away showing a detailed configuration of a non-aqueous electrolyte square secondary battery.

FIG. 3 is a schematic perspective view for explaining deformation of a negative electrode can in a normal use state of a non-aqueous electrolyte square secondary battery.

FIG. 4 is a schematic top view and a schematic side view for describing a battery storage space of an electronic device using a non-aqueous electrolyte square secondary battery.

FIG. 5 is a schematic sectional view showing a procedure for welding a sealing member.

6A and 6B are a schematic cross-sectional view and a schematic diagram, respectively, for explaining selection of a position where an injection hole is formed on a wide side surface of the negative electrode can.

FIG. 7 is a schematic sectional view showing a configuration of a sealing member according to another embodiment.

FIG. 8 is a schematic top view, a schematic cross-sectional view, and a schematic side view, partially cut away, showing a configuration of a nonaqueous electrolyte square secondary battery according to another embodiment.

FIG. 9 is a schematic perspective view showing a configuration of a conventional non-aqueous electrolyte square secondary battery with a part thereof cut away.

FIG. 10 is a schematic cross-sectional view for explaining sealing of the outer can.

FIG. 11 is a schematic perspective view of a non-aqueous electrolyte square secondary battery in which a welding position of a sealing member is changed, with a part thereof cut away.

FIG. 12 is a schematic cross-sectional view for explaining welding of a sealing member to a negative electrode can with a changed welding method.

[Explanation of symbols]

20, 70 ... non-aqueous electrolyte square secondary battery, 25 ... flat wound electrode body, 30 ... negative electrode can, 30A ... wide side surface, 3
OB: narrow side surface, 31, 73: can lid, 32: outer can, 40: battery storage space, 41, 60, 61, 6
2, 63 ... sealing member, 44 ... injection hole, 50 ... metal member, 71 ... positive electrode can.

Claims (2)

[Claims] An electrode body having a positive electrode and a negative electrode; an electrolyte serving as a medium for ion conduction between the positive electrode and the negative electrode of the electrode body; In order to inject the electrolyte into the outer peripheral portion of the wide side surface which is expanded and deformed so that the center portion of the adjacent side surfaces expands and swells most in the normal use state while the body is housed and the electrolyte is injected. A battery device comprising: an outer can having an injection hole formed therein; and a sealing member for sealing the injection hole of the outer can. 2. The battery device according to claim 1, wherein the injection hole is formed in a corner of the wide side surface of the outer can.