JP2001176471A - Battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a batter pack, offering easy assembly and simple construction allowing a smaller size, a smaller weight and a lower profile and permitting maximum advantage of using a thin-type battery, while maintaining rigidity as desired. SOLUTION: With sealing portions 34, 35 of the thin-type battery 18 covered with fold-back portions 42, 44 of respective thin plate reinforcing members 39, 40 and contact portions 43, 45 applied to the single side of the thin-type battery 18, so as to fit a fitting protruded portion 46 and a fitting recessed portion 47 to each other, the thin plate reinforcing members 39, 40 are mounted on the thin-type battery 18 to form the battery pack.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a battery pack.

[0002]

2. Description of the Related Art Conventionally, a battery of a small portable device such as a portable telephone or a PHS (simplified portable telephone) is charged by mounting a component 2 such as an IC on a side surface of a battery cell 1 as shown in FIG. A circuit board 3 for control and electrical protection of a battery is disposed via an insulating sheet 4 and a spacer 5, and a positive electrode terminal 6 spot-welded to an electrode at one end of the circuit board 3 is connected to the battery cell 1. The negative terminal 7 spot-welded to the positive electrode (not shown) and the electrode at the other end of the circuit board 3 is spot-welded to the negative electrode 8 of the battery cell 1 to form the positive terminal 6 and the negative terminal 7. Are respectively covered with a terminal sheet 9, and a base end of a connection cord 11 having a connector 10 at a front end extended from the circuit board 3 is fixed to the battery cell 1 with a reinforcing tape 12. Further, the surface of the circuit board 3 is covered with a protective plate 13, and the heat shrink tube 14 is shrunk by covering the entire battery cell 1 with a heat shrink tube 14 and heating the heat shrink tube 14 to a required temperature. A nameplate 15 indicating the model name, rating, and the like is attached to the surface of the battery, and the connector 10 is connected to the connector of the portable device as a completed battery as shown in FIG. And is loaded into the portable device.

Since the battery cell 1 is usually covered with an aluminum case, it has sufficient rigidity, but is not always sufficient from the viewpoint of miniaturization, light weight and thinness. .

For this reason, recently, as shown in FIG. 7, a unit cell 16 having a positive electrode and a negative electrode is hermetically sealed with a laminate film 17 to reduce the size, weight, and thickness of a lithium secondary battery or the like. A battery 18 has been developed, and it has been proposed to connect a circuit board (not shown) to the ± current collecting terminals 19 and 20 of the thin battery 18 and use it as a battery for a portable device.

However, in the case of a thin battery 18 as shown in FIG. 7, it is unavoidable that the thin battery 18 alone is insufficient in rigidity. Therefore, the thin battery 18 may be housed in a resin protective case and used as a battery pack. I have.

Conventionally, as this kind of battery pack, for example, there is one disclosed in Japanese Patent Application Laid-Open No. 10-208720. As shown in FIG. It has a configuration in which a thin battery 18 such as a lithium secondary battery sealed with a laminate film 17 having a three-layer structure of film-metal foil-resin film is housed in a protective case 21 made of resin.

The unit cell 16 includes, for example, a positive electrode 22, a solid polymer electrolyte layer 23 which is a lithium ion conductive electrolyte layer, a negative electrode 24, a solid polymer electrolyte layer 23, and a positive electrode 2.
2 are laminated. The positive electrode 22 has a structure in which a positive electrode layer 26 is supported on both surfaces of a porous current collector 25 made of Al. The negative electrode 24 is made of a porous current collector 27 made of Cu.
Has a structure in which a negative electrode layer 28 is supported on both surfaces. The positive electrode terminal portion 29 made of Al and the negative electrode terminal portion 30 made of Cu
One end of the unit cell 16 is integrally connected to the porous current collectors 25 and 27 while being shifted from each other. Ni for positive electrode
One end of a current collecting terminal 19 formed by a lead made of a lead is connected to the positive electrode terminal portion 29 made of Al at the fusion portion of the laminate film 17, and the other end is connected to the outside from the fusion portion of the laminate film 17. Has been extended. One end of a current collecting terminal (not shown) formed of a Ni lead for the negative electrode is connected to the negative electrode terminal portion 30 made of Cu at a fusion portion of the laminate film 17, and the other end is connected to the laminate film 17. Is extended to the outside from the fusion-bonded portion.

A current collecting terminal 19 formed of a Ni lead for a positive electrode and a current collecting terminal formed of a Ni lead for a negative electrode (shown in FIG. 1) extend from the fused portion of the laminate film 17 of the thin battery 18. ) Are connected to a positive external terminal 31 and a negative external terminal (not shown) provided on the side surface of the protective case 21, respectively.

A concave portion 32 is formed on the inner surface of the upper part of the protective case 21. A sharp projection 33 having a V-shaped cross section is integrally formed in the concave portion 32. A recess 32 slightly above the inner surface of the upper part of the protective case 21;
It is located on the side.

In the battery pack as shown in FIG. 8, while ensuring desired rigidity, it is possible to reduce the size, weight, and thickness of the battery pack. When the operation is performed, the lithium ion conductive electrolyte is decomposed to generate carbon dioxide gas, ethylene gas, and the like, and the space filled with the laminate film 17 that accommodates the unit cell 16 fills and the laminate film 17 expands. In this case, the expanded laminate film 17 comes into contact with a sharp projection 33 having a V-shaped cross section integrally formed in the recess 32 at the upper part of the protective case 21 for housing the thin battery 18. As a result, it is avoided that the protective case 21 is deformed by the expanded laminate film 17 and eventually the protective case 21 is damaged, It is possible to prevent the gas ejection and non-aqueous electrolyte from leaking to the section occurs, the battery pack is adapted to damage the portable device to be loaded is avoided.

[0011]

However, recently, there has been a demand for further reduction in size, weight and thickness, and FIG.
At present, it has become impossible to say that a battery pack as shown in FIG.

In the case of a battery pack as shown in FIG. 8, the protective case 21 is usually divided into upper and lower cases, and the upper and lower cases are mounted by ultrasonic welding with the thin battery 18 loaded in the upper and lower cases. The case is designed to be integrated. However, if the protective case 21 is formed by integrating the upper and lower cases by ultrasonic welding as described above, it takes a lot of time and effort to assemble, resulting in an increase in cost. Had.

In view of such circumstances, the present invention has a simple structure that is easy to assemble, can achieve desired rigidity, can be reduced in size, weight, and thickness, and can maximize the advantage of using a thin battery. It is intended to provide a battery pack that can be used to the fullest extent.

[0014]

SUMMARY OF THE INVENTION The present invention is directed to a folded portion for covering a sealing portion formed at one longitudinal edge of a thin battery obtained by sealing a unit cell having a positive electrode and a negative electrode with a laminate film; Forming a first thin plate reinforcing member having a plate portion extending from the folded portion to an intermediate portion in the longitudinal direction of the thin battery along one surface of the thin battery; A second thin plate reinforcing member having a folded portion that covers the sealing portion formed on the thin plate battery and a corresponding plate portion that extends from the folded portion to a middle portion in the longitudinal direction of the thin battery so as to be along one surface of the thin battery. Along with forming, at the edge of the thin plate reinforcing member on the side opposite to the folded portion in the plate portion,
Forming a fitting protrusion and a fitting recess that can be fitted to each other, cover the folded portion of each thin plate reinforcing member over the sealing portion of the thin battery, and make the fitting protrusion and the fitting recess mutually The present invention relates to a battery pack characterized in that a thin plate battery is provided with a thin plate reinforcing member by applying the plate portion to one side of the thin battery so as to fit.

In the battery pack, the outer periphery of the thin battery on which the thin plate reinforcing member is mounted can be covered with a film-like member, and a heat-shrinkable tube can be used as the film-like member.

Further, an opening for avoiding interference with a current collecting terminal extending from the sealing portion along one surface of the thin battery can be formed in the thin plate reinforcing member.

According to the above means, the following effects can be obtained.

The folded portion of each thin plate reinforcing member is covered over the sealing portion of the thin battery, and the plate portion is applied to one surface of the thin battery so that the fitting projection and the fitting recess fit together. When the thin plate reinforcing member is attached to the thin battery, the thin battery alone is inevitably insufficient in rigidity, and the laminated film may be damaged particularly when the sealing portion is applied or bent. However, in the case of the present invention, the sealing portion is covered with the folded portion of the thin plate reinforcing member, and is protected from deformation and breakage due to external stress, and the thin plate reinforcing member is provided on one side of the thin battery. This plate part is applied, strength is secured, and moreover,
The thin plate reinforcing member is located only on one side of the thin battery, and the thickness of the battery pack is kept to a minimum. As compared with the case where it is used, it is possible to make it smaller, lighter and thinner, and it is not necessary to perform ultrasonic welding or the like.

In the battery pack, when the outer periphery of the thin battery on which the thin plate reinforcing member is mounted is covered with a film-like member, a battery pack in which the thin plate reinforcing member is more reliably integrated with the thin battery is formed. When a heat-shrinkable tube is used as the film-like member, the heat-shrinkable tube shrinks only by covering the outer periphery of the thin battery with the thin plate reinforcing member with the heat-shrinkable tube and heating the heat-shrinkable tube to a required temperature. Then, the thin battery and the thin plate reinforcing member are integrated with each other, so that the assembling becomes easier.

Further, when an opening is formed in the thin plate reinforcing member to avoid interference with a current collecting terminal extending along one surface of the thin battery from the sealing portion, the thin plate reinforcing member can be applied to one surface of the thin battery. The adhesion of the plate portion is increased, and the thickness of the entire battery pack is prevented from being increased by the thickness of the current collecting terminal.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 4 show an embodiment of the present invention. In the drawings, the parts denoted by the same reference numerals as those in FIGS. 5 to 8 represent the same parts. A sealing portion 34 formed at one longitudinal edge of a thin battery 18 in which a unit cell 16 is sealed with a laminate film 17 is bent into a U-shaped cross section. The sealing portion 35 formed at the edge portion is held in a flat crimped cross section I-shape, and the current collecting terminal 1 extending from the sealing portion 34 bent into the U-shaped cross section.
The terminals 9 and 20 are disposed along one surface of the thin battery 18, and extend at one end of the current collecting terminals 19 and 20 to extend toward the flat sealing portion 35 along one surface of the thin battery 18. Terminals 36 and 37 are connected, and a substrate 38 disposed on the back side of the flat sealing portion 35 is connected to the tip of the extension terminals 36 and 37, not shown from the substrate 38. A connection cord 11 with a connector 10 attached to the tip of the connector for connection to the connector on the mobile device side is pulled out.

On the other hand, in the drawing, reference numeral 39 denotes a first thin plate reinforcing member formed of plastic or the like, 40 denotes a second thin plate reinforcing member formed of plastic or the like, and 41 denotes a film-like member such as a heat-shrinkable tube. And the first thin plate reinforcing member 39
A folded portion 42 covering a sealing portion 34 formed at one longitudinal edge of the thin battery 18;
And a contact plate portion 43 extending to a longitudinal middle portion of the thin battery 18 along one surface of the thin battery 18.
Further, the second thin plate reinforcing member 40 has a folded portion 44 that covers the sealing portion 35 formed at the other end in the longitudinal direction of the thin battery 18, and extends from the folded portion 44 along one surface of the thin battery 18. And a contact plate portion 45 extending to an intermediate portion in the longitudinal direction of the thin battery 18.
0 anti-folding portions 42, 44 in the plate portions 43, 45
A fitting protrusion 46 and a fitting recess 47 that can be fitted to each other are formed at the side edge portions, and the thin plate reinforcing members 39,
The folded portions 42, 44 of the thin battery 18 are covered with the sealing portions 34, 35 of the thin battery 18, and the plate portions 43, 45 are so fitted that the fitting projection 46 and the fitting recess 47 are fitted to each other. 18 is applied to one side, so that the thin battery 18
Then, thin plate reinforcing members 39 and 40 are mounted on the thin battery 18 and the outer periphery of the thin battery 18 to which the thin plate reinforcing members 39 and 40 are mounted is covered with a film-like member 41 to constitute a battery pack.

Incidentally, the abutting plate portion 43 of the first thin plate reinforcing member 39 avoids interference with the current collecting terminals 19 and 20 extending from the sealing portion 34 along one surface of the thin battery 18. The slits 50 for pulling out the connection cord 11 connected to the thin battery 18 are formed at required positions in the folded portion 44 of the second thin plate reinforcing member 40. It is.

Next, the operation of the above illustrated example will be described.

The folded portion 4 of each thin plate reinforcing member 39, 40
2 and 44 are covered with the sealing portions 34 and 35 of the thin battery 18, and the abutment portions 43 and 45 are applied to one surface of the thin battery 18 so that the fitting projection 46 and the fitting recess 47 are fitted to each other. Thereby, the thin plate reinforcing member 3
A film-like member 41 such as a heat-shrinkable tube is put on the outer periphery of the thin battery 18 to which the thin-plate reinforcing members 39 and 40 are attached. Accordingly, when the film-shaped member 41 is contracted, the thin battery 18 and the thin plate reinforcing members 39 and 40 are integrated, and a battery pack is formed.

The thin battery 18 alone is inevitably insufficient in rigidity. In particular, when the sealing portions 34 and 35 are subjected to a force or bent, the laminated film 17 may be damaged. In the case of the example shown, the sealing portion 34,
35 is a folded portion 42, 44 of the thin plate reinforcing members 39, 40.
To protect the battery from deformation and breakage due to external stress, and apply the plate portions 43, 45 of the sheet reinforcing members 39, 40 to one side of the thin battery 18,
The strength is secured by being covered with the film-like member 41, and furthermore, the contact plate portion 4 of the thin plate reinforcing members 39, 40 is provided.
3 and 45 are disposed only on one side of the thin battery 18 and are covered with a thin film-shaped member 41, and the thickness of the battery pack is minimized. Compared to being housed in the protective case 21 and used as a battery pack, it can be made smaller, lighter and thinner, and does not require ultrasonic welding, etc. Connect.

The current collecting terminals 19, 2 of the thin battery 18
If the connecting portion between the 0 and the extension terminals 36 and 37 folds and protrudes from other portions, and if the contact portion 43 of the first thin plate reinforcing member 39 is directly covered on one surface of the thin battery 18, The adhesion of the contact portion 43 of the first thin plate reinforcing member 39 to one surface of the thin battery 18 is impaired, and the thickness of the entire battery pack is increased by that amount. An opening 4 for avoiding interference with the current collecting terminals 19 and 20 extending from the sealing portion 34 along one surface of the thin battery 18 is formed in the contact plate portion 43.
8 and 49, the adhesion of the contact portion 43 of the first thin plate reinforcing member 39 to one surface of the thin battery 18 is increased, and the thickness of the current collecting terminals 19 and 20 is equal to that of the entire battery pack. Thickening is avoided.

In this way, with a simple structure that is easy to assemble,
It is possible to reduce the size, weight and thickness while securing the desired rigidity, and it is possible to maximize the advantages of using the thin battery 18.

Incidentally, the battery pack of the present invention is not limited to the above-described example shown in the drawings. Instead of using the film-like member 41 only by attaching the thin plate reinforcing members 39 and 40 to the thin battery 18, the present invention is not limited thereto. Insert the configured battery pack
It goes without saying that various changes can be made without departing from the spirit of the present invention, such as that it may be fixed to a battery cover of a portable device housing (not shown).

[0031]

As described above, the first aspect of the present invention is as described above.
According to the battery pack described, a simple structure that is easy to assemble, it is possible to reduce the size, weight, and thickness while maintaining the desired rigidity, and maximize the advantages of using a thin battery Can have an excellent effect of being able to
According to the battery pack according to the second aspect of the present invention, in addition to the above-described effects, an excellent effect that the integration of the thin plate reinforcing member to the thin battery can be more reliably achieved can be achieved,
According to the battery pack of the third aspect of the present invention, in addition to the above-described effects, an excellent effect that the assembling can be performed more easily can be achieved.
According to the battery pack described above, in addition to the above-described effects, it is possible to improve the adhesion of the thin plate reinforcing member to one side of the thin battery and to improve the adhesion of the thin plate, and to achieve an excellent effect of making the entire battery pack thinner. .

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state before assembling a thin battery, a thin plate reinforcing member, and a film-like member in an example of an embodiment of the present invention.

FIG. 2 is a perspective view showing a state in which a thin plate reinforcing member is attached to a thin battery in an example of an embodiment of the present invention.

3 is a side sectional view showing a state in which a thin plate reinforcing member is attached to a thin battery according to an example of an embodiment of the present invention, and is a view corresponding to the view taken along the line III-III of FIG. 2;

FIG. 4 is a perspective view showing a state in which the outer periphery of a thin battery to which a thin plate reinforcing member is attached according to an embodiment of the present invention is covered with a film-like member.

FIG. 5 is an exploded perspective view illustrating an example of a conventional battery.

FIG. 6 is a perspective view illustrating a completed state of an example of a conventional battery.

FIG. 7 is a perspective view illustrating an example of a conventional thin battery.

FIG. 8 is a side sectional view illustrating an example of a conventional battery pack.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 16 Unit cell 17 Laminated film 18 Thin battery 19 Current collecting terminal 20 Current collecting terminal 22 Positive electrode 24 Negative electrode 34 Sealing part 35 Sealing part 39 Thin plate reinforcing member 40 Thin plate reinforcing member 41 Film-like member 42 Folding part 43 This plate part 44 Folding Part 45 This plate part 46 Fitting convex part 47 Fitting concave part 48 Opening 49 Opening

Claims (4)

[Claims] 1. A folded portion that covers a sealing portion formed at one longitudinal edge of a thin battery obtained by sealing a unit cell having a positive electrode and a negative electrode with a laminate film, and a single side of the thin battery from the folded portion. Forming a first thin plate reinforcing member having an abutment portion extending to an intermediate portion in the longitudinal direction of the thin battery along the thin battery, and a sealing portion formed at the other longitudinal end edge of the thin battery. Forming a second thin plate reinforcing member having a folded portion to cover and a plate portion extending from the folded portion to an intermediate portion in the longitudinal direction of the thin battery along one surface of the thin battery; A fitting projection and a fitting recess that can be fitted to each other are formed at the edge of the member opposite to the side opposite to the folded portion, and the folded portion of each thin plate reinforcing member is sealed with the sealing portion of the thin battery. And the fitting projections and fitting recesses are A battery pack characterized in that a thin plate reinforcing member is attached to a thin battery by applying the contact plate portion to one side of the thin battery so as to fit the same. 2. The battery pack according to claim 1, wherein the outer periphery of the thin battery on which the thin plate reinforcing member is mounted is covered with a film-like member. 3. The battery pack according to claim 2, wherein a heat-shrinkable tube is used as the film-like member. 4. The battery pack according to claim 1, wherein an opening is formed in the thin plate reinforcing member to avoid interference with a current collecting terminal extending along one surface of the thin battery from the sealing portion. .