JP3519953B2 - Rechargeable battery - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a secondary electrode in which a winding electrode body is housed inside a battery can and the generated power of the winding electrode body can be taken out from an electrode terminal mechanism attached to the battery can. It concerns batteries.

[0002]

2. Description of the Related Art In recent years, lithium secondary batteries, which have high energy density and do not contain harmful substances such as cadmium and lead, have been attracting attention as power sources for portable electronic devices, electric vehicles and the like. For example, as shown in FIGS. 7 and 8, a cylindrical lithium secondary battery of a relatively large capacity used in an electric vehicle has lids (12) and (12) welded and fixed to both ends of a tubular body (11). The winding electrode body (28) is placed inside the cylindrical battery can (1)
It is configured to accommodate. A pair of positive and negative electrode terminal mechanisms (9) and (9) are attached to both lids (12) and (12), and the winding electrode body (28) and both electrode terminal mechanisms (9) and (9) are , A pair of electrode terminal mechanisms (9), (9) that are connected to each other by a plurality of current collecting tabs (3) and generate electric power generated by the winding electrode body (28).
It is possible to take it out from the outside. Also, the lid
A safety valve (13) is attached to (12).

The winding electrode body (28), as shown in FIG.
Between the positive electrode containing the lithium composite oxide (21) and the negative electrode containing the carbon material (23), a separator (22) impregnated with a non-aqueous electrolyte.
Is interposed and these are spirally wound. The winding work is performed using a metal core,
After the winding is completed, the winding core is extracted from the winding electrode body (2). As a result, the winding electrode body (28) has a hollow portion (2
9) will be formed. Positive electrode of winding electrode body (2)
Plural current collecting tabs (3) are drawn out from the negative electrode (23) and the negative electrode (23) respectively, and the tip portions (3) of the plural current collecting tabs (3) having the same polarity are drawn.
1) is connected to one electrode terminal mechanism (9). It should be noted that, in FIG. 9, for convenience, only the state in which the tips of some of the current collecting tabs are connected to the electrode terminal mechanism (9) is shown, and for the other current collecting tabs, the tips of the current collecting tabs are shown in the electrode terminal mechanism (9). Illustration of the state of being connected to 9) is omitted.

The electrode terminal mechanism (9) is a cover (1) for the battery can (1).
The screw member (91) is attached so as to pass through 2), and a flange portion (92) is formed at the base end of the screw member (91). An insulating packing (93) is attached to the through hole of the lid body (12) to maintain electrical insulation and sealing between the lid body (12) and the fastening member (91). A washer (94) is fitted to the screw member (91) from the outside of the tubular body (11), and a first nut (95) and a second nut (96) are screwed together. These nuts (95) (9
Tighten (6) and tighten the collar (92) and washer (9) of the screw member (91).
By pinching the insulating packing (93) with 4),
Improves sealability. The tip portions (31) of the plurality of current collecting tabs (3) are fixed to the collar portion (92) of the screw member (91) by spot welding or ultrasonic welding.

In the manufacturing process of the cylindrical lithium secondary battery, the electrode terminal mechanism (9) is attached to the lid body (12) which constitutes the battery can (1), while the electrode terminal mechanism (9) is wound inside the tubular body (11). With the take-up electrode body (28) inserted, the tip portions (31) of the plurality of current collecting tabs (3) extending from the take-up electrode body (28) are connected to the collar portion (92) of the electrode terminal mechanism (9). Welded to, and finally, the lid (12)
They were put on the opening of 1) and welded and fixed to each other.
-See 267528 [H01M2 / 26]).

[0006]

However, in the conventional cylindrical lithium secondary battery, since the winding electrode body is not fixed in the battery can, the vibration is generated particularly when mounted on a vehicle such as an electric vehicle. By adding the winding electrode body (28) housed in the battery can (1),
It vibrates in (1), the welding part of the current collecting tab (3) peels off,
The separator (22) of the winding electrode body (28) was damaged and the positive electrode (2
There was a risk of short-circuiting between 1) and the negative electrode (23).

Further, the work of welding the plurality of current collecting tabs (3) to the collar portion (92) is difficult and requires a long working time. However, since the current collecting tab (3) is formed of a foil body made of aluminum or nickel having a thickness of about 20 μm, the welded portion may be melted and a hole may be formed. There is a problem that the connection strength of (3) is significantly reduced. Even if normal welding is performed without forming holes, the area of the welded portion of the current collecting tab (3) and the collar portion (92) is extremely small, so that a large connection strength cannot be obtained.

The object of the present invention is to prevent the winding electrode body from vibrating in the battery can even when vibration is applied, and to easily connect the current collecting tab to the electrode terminal mechanism with high strength and reliability. It is to provide a secondary battery that can be used.

[0009]

In a secondary battery according to the present invention, a winding electrode is provided inside a battery can (1) having a lid (12) fixed to an opening of a cylinder (11). The body (2) is accommodated, the electrode terminal mechanism (4) is attached to the lid body (12) of the battery can (1), and the winding electrode body (2) and the electrode terminal mechanism (4) are plural. Are connected to each other by current collecting tabs (3). A winding core (20) is provided at the center of the winding electrode body (2). The winding electrode body (2) is fixed in the battery can (1) by sandwiching both ends of the winding core (20) from both sides in the battery can (1). The electrode terminal mechanism (4) is inserted into the through hole (14) formed in the lid body (12), and the lid body (12) is kept in an electrically insulating and liquid-tight manner. 12), fixed to the lid (1
The head protruding to the outside of 2) has a screwing operation part, while the tip protruding to the inside of the lid (12) has a center of the battery can (1) by the screwing operation of the screwing operation part. It has a pressing surface that advances toward the section. On the other hand, an electrode terminal mechanism is provided at the end of the winding core (20) of the winding electrode body (2).
A pressing receiving surface that is engageable with the pressing surface is formed facing the pressing surface of (4). The tip ends of the plurality of current collecting tabs (3) are sandwiched between the pressing surface of the electrode terminal mechanism (4) and the pressing receiving surface of the winding core (20) and connected to the electrode terminal mechanism (4). ing.

In assembling the secondary battery of the present invention,
A winding electrode body (2) is housed inside a cylindrical body (11) that should constitute a battery can (1), and tips of a plurality of current collecting tabs (3) extending from the winding electrode body (2). The part (31) is placed on the pressure receiving surface of the winding core (20), while the electrode terminal mechanism (4) is attached to the lid (12), and then the lid ( Put on 12).
As a result, the tips of the plurality of current collecting tabs (3) are temporarily fixed by being sandwiched between the pressing surface of the electrode terminal mechanism (4) and the pressing receiving surface of the winding core (20). . In this state, the cylinder
The lid (12) is fixed to the opening of (11) by welding or the like, and then the screwing operation portion of the electrode terminal mechanism (4) is screwed. As a result, the pressing surface of the electrode terminal mechanism (4) is pressed against the pressing receiving surface of the winding electrode body (2), and the winding electrode body (2) is clamped from both sides in the battery can (1), It is fixed in the battery can (1), and the tips of the current collecting tabs (3) are sandwiched between the pressing surface of the electrode terminal mechanism (4) and the pressing receiving surface of the winding core (20). Therefore, it is surely connected to the electrode terminal mechanism (4).

Therefore, the work of welding the tip ends of the plurality of current collecting tabs (3) to the electrode terminal mechanism (4) is unnecessary, and the pressing surface of the electrode terminal mechanism (4) and the winding core (20) are simply replaced. The tip of the current collecting tab (3) is sandwiched between the pressure receiving surfaces to form an electrode terminal mechanism.
The connection work of the current collecting tab (3) is completed only by screwing in (4). Also, the tip of each current collecting tab (3) contacts the pressing surface of the electrode terminal mechanism (4) in a sufficient area, and this sufficient contact area reduces the electrical resistance in the connecting portion, and at the same time makes a high connection. Strength is obtained. Since the conventional welding structure is not adopted for the connection structure by the pinching force, the current collecting tab (3) is not perforated, and high reliability is obtained. Even if the battery can (1) is vibrated in the assembled state, the winding electrode body (2) is securely sandwiched from both sides inside the battery can (1). It does not vibrate inside.

Specifically, the electrode terminal mechanism (4) includes a lid (1
A holding member (5) formed by forming a screwing operation portion on the head of a screw shaft portion (52) penetrating the through hole (14) of 2), and a holding member (5)
A plurality of pinching nuts (6) (7) for fixing the holding member (5) to the lid body (12) by screwing with the screw shaft portion (52) of the lid, and the lid body (12).
It is installed in the through hole (14) of the device and is interposed between the lid body (12) and the sandwiching member (5), and is sandwiched by the sandwiching nuts (6) and (7) to form the lid body (12). An insulating packing (8) (81) for maintaining electrical insulation and liquid tightness between the holding members (5),
The tip surface of (5) forms the pressing surface. In this specific configuration, the pressing surface of the holding member (5) is pressed against the pressing receiving surface of the winding core (20) by screwing the holding member (5).

Further, specifically, at the tip end surface of the holding member (5) and the end surface of the winding core (20) facing the tip end surface, the convex portion (53) on one side and the concave portion (25) on the other side. Is formed, and the convex portion (53) and the concave portion (25) are engaged with each other. In the specific configuration, the convex portion (53) and the concave portion (25) are engaged with each other in the process of screwing the holding member (5) and holding the winding electrode body (2) from both sides, The tip surface (pressing surface) of the holding member (5) is the winding core.
There is no positional deviation with respect to the end face (pressure receiving face) of (20).

In a more specific structure, the winding core (20) is provided with a slit (24) through which the tip of the separator (22) constituting the winding electrode body (2) is inserted.
In the specific configuration, in the manufacturing process of the winding electrode body (2), when the separator (22) is first wound around the outer peripheral surface of the winding core (20), the tip of the separator (22) is wound. The core (20) is inserted into the slit (24), and the winding core (20) is rotated in this state. This allows the separator (2
2) will be wrapped. Therefore, the separator (2
It is not necessary to adhesively fix the tip of 2) to the outer peripheral surface of the winding core (20), which improves the efficiency of the winding operation.

In the battery can (1) having the lids (12) and (12) fixed to both openings of the tubular body (11), the electrode terminal mechanism (4) is attached to each lid (12). When attached, the winding electrode body (2)
Is a pair of electrode terminal mechanisms (4) (4) with both ends of the winding core (20)
The sandwiching members (5) and (5) are sandwiched from both sides and securely fixed in the battery can (1). In this case, the entire winding core (20) is formed from an insulating material, or at least a part sandwiched between one end or both ends in the longitudinal direction is formed from an insulating material, thereby forming a winding core ( 20)
It is possible to prevent a short circuit between the positive and negative collector tabs (3) (3) connected to both ends of the. On the other hand, one lid (12)
When the above-mentioned electrode terminal mechanism (4) is attached to only one, a structure in which the other end of the winding core (20) is received by the inner surface of the other lid (12) can be adopted.

[0016]

In the secondary battery according to the present invention, since the winding electrode body (2) is clamped and fixed from both sides in the battery can (1), even if it receives vibration from the outside, The winding electrode body (2) does not vibrate in the battery can (1). Further, the current collecting tab (3) has its tip end wound up with an electrode body.
Since the structure is adopted in which it is sandwiched between the pressing surface of (2) and the pressing receiving surface of the winding core (20) and connected to the electrode terminal mechanism (4), the conventional welding work is unnecessary and the connection is made. The work is easy. In addition, since there is no hole in the current collecting tab (3) due to the connecting work, the current collecting tab (3) can be pressed against the electrode terminal mechanism (4) with a sufficient contact area. And high reliability is obtained.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment in which the present invention is applied to a cylindrical lithium secondary battery will be specifically described with reference to the drawings. The cylindrical lithium secondary battery according to the present invention is shown in FIG.
As shown in FIG. 2, a cylindrical battery can (1) is formed by welding and fixing lids (12) and (12) to both ends of the tubular body (11), and both lids (12) and (12) are provided.
A pair of positive and negative electrode terminal mechanisms (4) and (4) are attached to the. A safety valve (13) is attached to each lid (12).

The winding electrode body (2) shown in FIG. 4 is housed inside the battery can (1). Winding electrode body (2)
Is a separator in which a non-aqueous electrolyte is impregnated between a positive electrode (21) containing a lithium composite oxide and a negative electrode (23) containing a carbon material.
(22) is interposed, and these are spirally wound around the outer peripheral surface of the winding core (20). The winding core (20) is made of an insulating resin such as polypropylene or polyethylene, or ceramics, etc., and circular recesses (25) are formed on both end faces in the longitudinal direction. Further, the positive electrode (21) and the negative electrode (23) are respectively joined to the base end portions of a plurality of current collecting tabs (3) by spot welding or the like, and the tip end portions thereof are wound electrode bodies.
It projects from (2). The collector tab (3) joined to the positive electrode (21) is made of aluminum foil, and the collector tab (3) joined to the negative electrode (23) is made of copper foil.

A pair of positive and negative electrode terminal mechanisms shown in FIG. 1 (4)
Of the four (4), one of the electrode terminal mechanisms (4) serving as a positive electrode terminal is connected with a plurality of current collecting tabs (3) drawn from the positive electrode (21), and the other serves as a negative terminal. Electrode terminal mechanism
A plurality of current collecting tabs (3) drawn from the negative electrode (23) are connected to (4). As a result, the electric power generated by the winding electrode body (2) is supplied to the pair of positive and negative electrode terminal mechanisms.
(4) It can be taken out from (4).

As shown in FIG. 3, the lid (12) has a through hole (14) in the center and a screw hole (15) in the outer periphery, and the through hole (14) has an electrode terminal. Mechanism (4) is attached,
The safety valve (13) is screwed into the screw hole (15).

The electrode terminal mechanism (4) has the structure shown in FIGS. That is, in the through hole (14) of the lid body (12),
As shown in FIG. 2, a pair of insulating packings (8) and (81) are mounted in a state of being engaged with each other. As shown in FIG. 5, the upper insulating packing (8) is formed of a disk portion (85) and a cylindrical portion (86), while the lower insulating packing (81) is formed in a ring shape and is engaged with each other. In the state, the through hole (14) of the lid body (12)
It adheres to the inner peripheral surface and the inner peripheral edge of the.

A sandwiching member that penetrates through the central holes of the pair of insulating packings (8) and (81) mounted in the through holes (14) of the lid body (12).
(5) is inserted from the outside of the lid (12). Holding member (5)
Is a hexagonal prism screw-in operation part (51) on the head of the screw shaft part (52).
And a protrusion (53) which can be fitted into the recess (25) of the winding core (20) is formed on the lower end surface. The screw shaft portion (52) of the holding member (5) is screwed with the first holding nut (6) and the terminal nut (61) on the outside of the lid body (12), and at the same time, the lid body (12). The second pinching nut (7) is screwed inside of the, and the insulating packing (8) (81) is pinched by the first pinching nut (6) and the second pinching nut (7). ing. Also, the lid
O between the disk (85) facing surface of (12) and the insulating packing (8)
The ring (82) is interposed, and the O-ring (83) is interposed between the disk portion (85) of the insulating packing (8) and the opposing surface of the pinching nut (6).

As shown in FIG. 2, the end face of the winding core (20) and the end face of the holding member (5) are pressed against each other, and the holding member (25) is formed in the recess (25) formed in the end face of the winding core (20). A convex portion (53) formed on the front end surface of 5) is fitted. As a result, the winding electrode body (2) has the winding core (20) having a pair of sandwiching members at both end surfaces thereof.
(5) The battery can is pinched from both sides by the tip surface of (5).
It is firmly fixed in (1). Then, the tip ends of the plurality of current collecting tabs (3) extending from the winding electrode body (2) are sandwiched between the end surface of the winding core (20) and the tip surface of the sandwiching member (5) to form an electrode terminal. It is connected to the mechanism (4).

In the manufacturing process of the cylindrical lithium secondary battery, first, the winding electrode body (2) shown in FIG. 4 is manufactured. As described above, the separator (22) impregnated with the non-aqueous electrolyte is interposed between the positive electrode (21) containing the lithium composite oxide and the negative electrode (23) containing the carbon material, and these are wound (20). ) Spirally wound around the outer peripheral surface. In the winding operation, as shown in FIG. 3, first, the tip of the separator (22) is attached to the core (2
Wrap the outer peripheral surface of 0) multiple times. Where the core (20)
The slit (2
4) is opened, by rotating the winding core (20) with the tip of the separator (22) inserted in the slit (24), the separator (22) is attached to the outer peripheral surface of the winding core (20). The tip can be wrapped. Therefore, it is not necessary to bond the tip of the separator (22) to the outer peripheral surface of the winding core (20), and the winding operation is easy. Then, the separator (2
As shown in FIG. 4, a positive electrode (21), a separator (22), and a negative electrode (23) are superposed on 2), and these are spirally wound. Here, a plurality of current collecting tabs (3) are spot-welded on the surfaces of the positive electrode (21) and the negative electrode (23) in advance.

Next, as shown in FIG. 6, the cylindrical body (1) of the battery can (1) is
The winding electrode body (2) is housed in 1), and the winding electrode body is
The tip ends (31) of the plurality of current collecting tabs (3) extending from (2) are placed on the end surface of the winding core (20). Further, the electrode terminal mechanism (4) is fixed to each lid (12). Here, the first pinching nut 6 and the second pinching nut 7 are tightened until sufficient liquid tightness is obtained by the insulating packings 8 and 81.

After that, both lids (12) and (12) are welded and fixed to both openings of the tubular body (11) by using laser welding or beam welding. As a result, as shown in FIG. 2, the tip surface of the pinching member (5) of the electrode terminal mechanism (4) contacts the end surface of the winding core (20),
Or, they will face each other with a slight interval. In this state, by screwing the sandwiching members (5) and (5) of the two electrode terminal mechanisms (4) and (4), both end surfaces of the winding core (20) are moved by the tip surfaces of both sandwiching members (5) and (5). While being pinched from both sides, the tip ends (31) of the plurality of current collecting tabs (3) are pinched between each end surface of the winding core (20) and the tip end surface of the pinching member (5).

Finally, after injecting the electrolytic solution into the battery can (1), the safety valve (13) is screwed and fixed to each lid (12) as shown in FIG. Type lithium secondary battery is completed.

As described above, in the cylindrical lithium secondary battery according to the present invention, the electrode terminal mechanism (4) has a collector tab (3).
In the step of connecting the two, the conventional welding work is unnecessary, and the tip portions (31) of the plurality of current collecting tabs (3) are simply connected to the end surfaces of the winding core (20) and the clamping member (5). The work can be done easily because it can be inserted into the
The current collecting tab (3) never has a hole, and high reliability is obtained. Further, since the tip end portion (31) of each current collecting tab (3) contacts the tip end surface of the sandwiching member (5) with a sufficient area, the electric resistance at the contact portion is small and high connection strength can be obtained.

Furthermore, the winding electrode body in the battery can (1)
In (2), since both end surfaces of the winding core (20) are clamped by the tip surfaces of the clamping members (5) and (5) and firmly fixed in the battery can (1), the cylinder according to the present invention Even when the type lithium secondary battery is mounted on an electric vehicle, the winding electrode body (2) does not vibrate in the battery can (1) due to the vibration.

[0030]

EXAMPLES Next, the results of performance comparison tests were carried out by making a prototype of the cylindrical lithium secondary battery of the present invention (FIGS. 1 to 3) and a conventional cylindrical lithium secondary battery (FIGS. 7 to 9). Will be described.

Preparation of Positive Electrode LiCoO ₂ (lithium composite oxide) powder having an average particle size of 5 μm as a positive electrode active material and artificial graphite as a conductive agent were mixed at a weight ratio of 9: 1 to prepare a positive electrode mixture. Next, polyvinylidene fluoride as a binder was dissolved in N-methyl-2-pyrrolidone (NMP) to prepare an NMP solution. Then, the weight ratio of the positive electrode mixture and polyvinylidene fluoride is 95:
The mixture of the positive electrode mixture and the NMP solution was mixed to give a slurry of 5 to prepare a slurry.
The aluminum foil having a thickness of μm was coated on both sides by a doctor blade method and dried at 150 ° C. for 2 hours to prepare a positive electrode.

Preparation of Negative Electrode A carbon powder (d ₀₀₂ = 3.356Å; Lc> 1000) was jetted with an air stream and pulverized to prepare a carbon powder. In addition, polyvinylidene fluoride, which is a binder, is dissolved in NMP to form NMP.
A solution was prepared and kneaded so that the weight ratio of carbon powder and polyvinylidene fluoride was 85:15 to prepare a slurry. This slurry was applied on both sides of a copper foil having a thickness of 20 μm to be a negative electrode current collector by the doctor blade method,
A negative electrode was prepared by vacuum drying at 2 ° C. for 2 hours.

Preparation of Electrolytic Solution LiPF ₆ was dissolved in a solvent prepared by mixing ethylene carbonate and diertyl carbonate at a volume ratio of 1: 1 at a ratio of 1 mol / l to prepare an electrolytic solution.

Preparation of Batteries of the Invention : A resin core having a diameter of 10 mm was wrapped with a separator, an ion-permeable polypropylene microporous membrane, several times, and the separator was interposed between the positive electrode and the negative electrode. Then, four sheets of a separator, a positive electrode, a separator, and a negative electrode were stacked and spirally wound many times to produce a wound electrode body. This winding electrode body is loaded inside the cylindrical body that will be the battery can,
The positive electrode and the negative electrode current collecting tabs extending from the winding electrode body are sandwiched between the winding member and the sandwiching member of the electrode terminal mechanism of the present invention attached to the lid body, and the lid body is cylindrical. After being fixed to the body by welding and further screwing in the holding member, the electrolytic solution was injected into the battery can to complete the cylindrical lithium secondary battery (the battery of the present invention) according to the present invention.

Preparation of Comparative Example Battery The battery of the present invention is the same as that of the battery of the present invention except that a winding core is not used and the electrode terminal mechanism and the current collecting tab are connected by a sandwiching structure by a sandwiching mechanism provided in the electrode terminal mechanism. A comparative battery was manufactured.

Evaluation of Battery To the battery of the present invention and the battery of the comparative example, vibration was applied for 100 minutes in the XYZ directions intersecting each other at an amplitude of 0.8 mm, a frequency of 10 to 55 Hz, and a sweep speed of 1 Hz / min at right angles.
The internal short circuit occurrence rate and output characteristics (DOD 50%, output density after 10 seconds of discharge) were examined. As a result, regarding the internal short-circuit occurrence rate, in the battery of the present invention, none of the 10 samples had a short circuit, but in the comparative example battery, a short circuit occurred in 4 of the 10 samples. Was. Regarding the output characteristics, the battery of the present invention has 573 to 591 W / Kg.
While the power density of 4 was obtained, the comparative battery was 478
The output density was ˜524 W / Kg. As is clear from these results, according to the secondary battery of the present invention, since the winding electrode body is sandwiched and fixed in the battery can, even if vibration is applied, the winding electrode body is held in the battery can. The body does not vibrate and the winding electrode body is not damaged.

The configuration of each part of the present invention is not limited to the above embodiment, and various modifications can be made within the technical scope described in the claims. For example, the engagement structure between the tip end surface of the sandwiching member (5) and the end surface of the winding core (20) is not limited to the concave and convex fitting,
Various known engagement structures can be adopted. Also, the holding member (5)
It is also possible to increase the contact area between the front end and the end of the winding core (20) by projecting a collar.

[Brief description of drawings]

FIG. 1 is a perspective view of a cylindrical lithium secondary battery according to the present invention.

FIG. 2 is a cross-sectional view showing a main part of the secondary battery.

FIG. 3 is a perspective view showing a process of winding the tip of the separator around the winding core.

FIG. 4 is a partial development view of a winding electrode body.

FIG. 5 is an exploded perspective view of an electrode terminal mechanism.

FIG. 6 is a cross-sectional view showing a process of fixing a lid body to which an electrode terminal mechanism is attached to a cylindrical body accommodating a winding electrode body.

FIG. 7 is a perspective view of a conventional cylindrical lithium secondary battery.

FIG. 8 is an exploded perspective view of the secondary battery.

FIG. 9 is a cross-sectional view showing a main part of the secondary battery.

[Explanation of symbols]

(1) Battery can (11) Cylindrical body (12) Cylindrical body (2) Winding electrode body (20) Winding core (25) Recess (3) Power collection tab (4) Electrode terminal mechanism (5) Holding member (51) Screw-in operation part (52) Screw shaft (53) Convex part (6) 1st pinch nut (7) Second pinch nut (8) Insulating packing (81) Insulating packing

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Nishio 2-5-5 Keihan Hondori, Moriguchi City, Osaka Sanyo Electric Co., Ltd. (56) Reference JP-A-9-35701 (JP, A) JP JP-A-11-339756 (JP, A) JP-A-11-312532 (JP, A) JP-A-11-283606 (JP, A) JP-A-11-329398 (JP, A) JP-A-11-162521 (JP , A) JP-A-11-195434 (JP, A) JP-A-11-250934 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01M 2/26 H01M 2/30 H01M 10/04 H01M 10/40

Claims (5)

(57) [Claims] 1. A winding electrode body (2) is housed in a battery can (1) having a lid body (12) fixed to an opening of a cylindrical body (11), and the winding electrode body (2) is ) Is formed by spirally winding a strip-shaped positive electrode (21) and a negative electrode (23) with a separator (22) interposed between both electrodes, and an electrode on the lid (12) of the battery can (1). The terminal mechanism (4) is attached, the winding electrode body (2) and the electrode terminal mechanism (4) are connected to each other by a plurality of current collecting tabs (3), and the winding electrode body (2) is generated. In the secondary battery in which the generated electric power can be taken out from the electrode terminal mechanism (4) to the outside, the winding core (2
0) is provided, and both ends of the winding core (20) are battery cans.
The electrode terminal mechanism (4) is sandwiched from both sides in (1) and fixed in the battery can (1), and the electrode terminal mechanism (4) has a through hole (1
4) is fixed to the lid body (12) in a state of being electrically insulated and liquid-tight to the lid body (12) by being inserted into the lid body (12), and the head portion protruding to the outside of the lid body (12). Is equipped with a screw-in operation part,
The tip of the lid (12) protruding inward is provided with a pressing surface that advances toward the central portion of the battery can (1) by the screwing operation of the screwing operation part, and the winding core facing the pressing surface.
A pressing receiving surface that can be engaged with the pressing surface is formed at the end of (20), and the tips of the plurality of current collecting tabs (3) are wound on the pressing surface of the electrode terminal mechanism (4) and the winding core. A secondary battery which is sandwiched between the pressure receiving surfaces of (20) and is connected to the electrode terminal mechanism (4). 2. The electrode terminal mechanism (4) is a holding member in which a screwing operation portion (51) is formed on the head of a screw shaft portion (52) penetrating the through hole (14) of the lid body (12). (5) and the screw shaft portion (52) of the holding member (5) are screwed together to hold the holding member (5).
Clamping nuts (6) (7) for fixing the to the lid (12)
And is inserted into the through hole (14) of the lid body (12), interposed between the lid body (12) and the holding member (5), and pinched by the pinching nuts (6) and (7). , And an insulating packing (8) (81) for maintaining electrical insulation and liquid tightness between the lid body (12) and the holding member (5), and the front end surface of the holding member (5) serves as the pressing surface. The secondary battery according to claim 1, which is formed. 3. A convex portion (53) is formed on one side and a concave portion (25) is formed on the other side on the tip surface of the holding member (5) and the end surface of the winding core (20) facing the tip surface. The secondary battery according to claim 2, wherein the convex portion (53) and the concave portion (25) are engaged with each other. 4. The winding core (20) is provided with a slit (24) through which the tip of the separator (22) constituting the winding electrode body (2) is inserted. The secondary battery according to any one of 3 above. 5. The lid (12) is provided at each of the openings of the tubular body (11).
Inside the battery can (1) with the
(2) is housed, and the winding electrode body (2) is formed by spirally winding a strip-shaped positive electrode (21) and a negative electrode (23) with a separator (22) interposed between both electrodes, A pair of electrode terminal mechanisms (4) and (4) are attached to both lids (12) and (12) of the can (1), and the winding electrode body (2) and each electrode terminal mechanism (4) are plural. The power generated by the winding electrode body (2), which is connected to each other by the current collecting tabs (3) of the pair of electrode terminal mechanisms (4).
In a secondary battery which can be taken out from (4), at least a part sandwiched between one end or both ends in the longitudinal direction is an insulating material in the center of the winding electrode body (2). A core (20) made of is provided, and each electrode terminal mechanism (4) is inserted into a through hole (14) formed in the lid (12) to electrically connect to the lid (12). The head, which is fixed to the lid (12) while maintaining insulation and liquid tightness, has a screwing operation part on the head protruding outside the lid (12), while inside the lid (12) The tip end projecting at is provided with a pressing surface that advances toward the center of the battery can (1) by the screwing operation of the screwing operation portion, and the end of the winding core (20) corresponding to the pressing surface is provided at the end portion. A pressing receiving surface that can be engaged with the pressing surface is formed, and both pressing receiving surfaces of the winding core (20) are a pair of electrode terminal mechanisms (4) (4)
The pressing surfaces of the current collecting tabs (3) are clamped from both sides, and the tips of the current collecting tabs (3) are clamped between the pressing surface of the electrode terminal mechanism (4) and the pressing receiving surface of the winding core (20). And a secondary battery which is connected to the electrode terminal mechanism (4).