JP2000231918A - Nonaqueous electrolyte secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent current exceeding a predetermined value from being continuously generated and to provide high energy density in a nonaqueous electrolyte secondary battery wherein a wound electrode body is housed in a battery can, and positive and negative electrodes constituting the wound electrode body are coated with electrode materials on the surfaces of band-like collectors. SOLUTION: At least one collector of positive and negative electrodes is constituted of a plurality of collector pieces 42 arranged in one direction and a PTC element 5 coupling adjacent collector pieces 42 each other. In this embodiment, at least one of the positive and negative electrodes is interposed between the opposit surfaces of the non-coated part of the collector and the base end part of a collector tab through the PTC element 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-aqueous electrolyte secondary battery having a battery can containing an electrode body serving as a power generating element, and more particularly to a non-aqueous electrolyte secondary battery when a current exceeding a predetermined value is generated. The present invention relates to a non-aqueous electrolyte secondary battery capable of rapidly suppressing the current.

[0002]

2. Description of the Related Art In recent years, lithium secondary batteries capable of increasing capacity and increasing energy density have attracted attention as power sources for electric vehicles and hybrid vehicles. For example, the cylindrical lithium secondary battery shown in FIGS. 4 and 5 has a cylindrical battery can (1) formed by welding and fixing lids (12) and (12) to both ends of a cylindrical body (11). , And accommodates the wound electrode body (2).
Both lids (12) and (12) have a pair of positive and negative electrode terminal mechanisms (9) (9)
Is attached, and the winding electrode body (2) and the two electrode terminal mechanisms (9) and (9) are connected to each other by a plurality of current collecting tabs (3), so that the winding electrode body (2) is The generated power can be taken out from the pair of electrode terminal mechanisms (9) (9). Further, a safety valve (13) is attached to the lid (12).

[0003] As shown in FIG.
A separator (22) impregnated with a non-aqueous electrolyte between a positive electrode (23) containing a lithium composite oxide and a negative electrode (21) containing a carbon material
And these are spirally wound. A plurality of current collecting tabs (3) are drawn out from the positive electrode (23) and the negative electrode (21) of the winding electrode body (2), respectively. ) Are connected to one electrode terminal mechanism (9) as shown in FIG. In FIG. 5, for the sake of convenience, the tip of a part of the current collecting tabs is connected to the electrode terminal mechanism.
Only the state connected to (9) is shown, and for the other current collecting tabs, the illustration of the tip portion connected to the electrode terminal mechanism (9) is omitted.

The electrode terminal mechanism (9) is provided with a lid (1) of the battery can (1).
The screw member (91) has a flange (92) formed at the base end of the screw member (91). An insulating packing (93) is attached to the through-hole of the lid (12), so that electrical insulation and sealing between the lid (12) and the fastening member (91) are maintained. A washer (94) is fitted into the screw member (91) from the outside of the cylindrical body (11), and a first nut (95) and a second nut (96) are screwed into the screw member (91). ) Is tightened, and the insulating packing (93) is clamped by the flange (92) of the screw member (91) and the washer (94) to enhance the sealing performance. The tips (31) of the plurality of current collecting tabs (3) are fixed to the flange (92) of the screw member (91) by laser welding or ultrasonic welding.

The positive electrode (23) and the negative electrode (21) of the wound electrode body (2)
As a structure for connecting the current collecting tab (3) to the surface, the surface of the strip-shaped current collector constituting each electrode is coated on the coated portion where the electrode material is coated and the uncoated portion where the electrode material is not coated. There is known a structure in which a base portion of a current collection tab is fixed to the uncoated portion by laser welding, ultrasonic welding, or the like.
(JP-A-6-267528 [H01M2 / 26]).

In the above-mentioned non-aqueous electrolyte secondary battery, when a short circuit or the like occurs in the battery, a large current may flow. For example, as shown in FIG. There has been proposed an electrode structure in which an electrode material (83) is disposed on both surfaces of a current collector (81) via PTC element layers (82), respectively (Japanese Patent Laid-Open No. 7-220755 [H01M10 / 38]). PTC
The PTC element constituting the element layer (82) is an element having a positive temperature coefficient of resistance, and when a current exceeding a predetermined value flows, its electric resistance value sharply increases, and a current suppressing effect is obtained. To demonstrate. According to the secondary battery, even if a short circuit or the like occurs inside the battery, a current exceeding a predetermined value does not continuously flow.

[0007]

However, in the conventional non-aqueous electrolyte secondary battery provided with the PTC element layer (82) shown in FIG. 7, the distance between the current collector (81) and the electrode material (83) is increased. To PTC
Since the element layer (82) is interposed, the amount of the electrode material (83) per unit volume of the battery can is smaller than that of the battery without the PTC element layer (82). As a result, there is a problem that the discharge capacity per unit volume of the battery can, that is, the energy density is greatly reduced.

An object of the present invention is to provide a non-aqueous electrolyte secondary battery capable of preventing continuous generation of a current exceeding a predetermined value and realizing a high energy density.

[0009]

In the nonaqueous electrolyte secondary battery according to the present invention, at least one of the positive electrode and the negative electrode constituting the electrode body (2) housed in the battery can (1) is The current collector is constituted by a plurality of current collector pieces (42) arranged in one direction and a PTC element (5) for connecting adjacent current collector pieces (42) to each other. It is characterized by being.

The non-aqueous electrolyte secondary battery according to the present invention employs a structure in which the PTC element (5) is interposed between the plurality of current collector pieces (42). Can be formed to the minimum length necessary to connect the current collector pieces (42), so that the volume occupied by the PTC element (5) inside the battery can (1) is: Compared to a conventional configuration in which a PTC element layer is interposed between a current collector and an electrode material,
Dramatically reduced. As a result, the amount of the electrode material increases as compared with the conventional case, and the energy density becomes a high value equivalent to that of a battery having no PTC element.

In a specific configuration, the ends of the pair of current collector pieces (42) to be connected to each other are connected to the PTC element (5).
Are sandwiched between the upper and lower sides, and are joined to both surfaces of the PTC element (5). According to this specific configuration, the junction area between the PTC element (5) and the current collector piece (42) can be made sufficiently large, and thereby the connection between the current collector pieces (42) is strong. It will be.

The number A of the current collector pieces 42, the total length B of the electrodes along the winding direction of the electrode body 2 and the length C of the PTC element 5 are: A × C / The relation of B <0.1 has been established. As demonstrated by the experimental results described later, by satisfying the above relationship, the discharge capacity is significantly increased as compared with the conventional case.

In the non-aqueous electrolyte secondary battery according to the present invention, the positive electrode and the negative electrode constituting the electrode body (2) housed in the battery can (1) are each formed of a strip-shaped current collector (61). On the surface, a coated portion to which the electrode material (62) is applied and a non-coated portion to which the electrode material (62) is not formed are formed, and the current collecting tab (3) is formed on the non-coated portion. Is connected to the current collecting tab
The tip of (3) is connected to the electrode terminal mechanism (9). At least one of the positive electrode and the negative electrode is provided with a PTC element (7) interposed between an uncoated portion of the current collector (61) and a facing surface of a base end of the current collecting tab (3). It is configured.

According to the non-aqueous electrolyte secondary battery of the present invention, the PTC is provided between the uncoated portion of the current collector (61) and the current collecting tab (3).
Since the structure of interposing the element (7) is adopted, PTC
The element (7) can be formed to have a length equal to the width of the current collecting tab (3), so that the PTC can be formed inside the battery can (1).
The volume occupied by the element (7) is greatly reduced as compared with a conventional configuration in which a PTC element layer is interposed between a current collector and an electrode material. As a result, the amount of the electrode material increases as compared with the conventional case, and the energy density becomes a high value equivalent to that of a battery having no PTC element.

In a specific configuration, the thickness of the PTC element (7) is 10 μm to 500 μm. As demonstrated by the experimental results described later, by forming the thickness of the PTC element (7) within the above range, a sufficient current suppressing effect is maintained and the discharge capacity is increased as compared with the conventional case.

[0016]

According to the non-aqueous electrolyte secondary battery according to the present invention, it is possible to prevent continuous generation of current exceeding a predetermined value and to realize high energy density.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention applied to a cylindrical lithium secondary battery will be specifically described below with reference to the drawings. In the secondary battery according to the present invention, in addition to the configuration in which the PTC element provides the current suppression function only to the positive electrode, a configuration in which the same current suppression function is provided only to both the positive electrode and the negative electrode or only the negative electrode can be employed. It is. The secondary battery according to the present invention is the same as the batteries shown in FIGS. 4 and 5 except for the specific configuration of the wound electrode body (2), and the same configuration will be described. Is omitted.

[0018]

First Embodiment In the secondary battery of the present embodiment, as shown in FIG. 1, a positive electrode (4) is provided with a plurality of current collector pieces (42) arranged in the winding direction of a winding electrode body. The electrode material (43) applied to both sides of each current collector piece (42), and the adjacent current collector pieces (42)
It comprises a PTC element (5) for connecting the parts to each other, and a coating part coated with an electrode material (43) and a coating part coated with an electrode material (43) on the surface of the current collector piece (42). An uncoated portion is formed, and the base end of the current collecting tab (3) is joined to the uncoated portion.

Here, a pair of adjacent collector pieces (42) (42)
As shown in the enlarged view of FIG. 1, the ends to be connected to each other by the PTC element (5) are vertically overlapped with the PTC element (5) interposed therebetween. Are bonded using a conductive adhesive (not shown).

In the manufacturing process of the positive electrode (4), FIG.
As shown in the figure, on the surface of a plurality of current collector pieces (42), respectively,
The electrode material (43) is applied except for the joining area of the current collecting tab (3) and the joining area of the PTC element (5).
A first non-coated portion (44) to be joined with (3) is formed, and second non-coated portions (45) and (45) to be joined with the PTC element (5) are formed at both ends. I do. As a result, a plurality of positive electrode pieces are obtained. Next, the adjacent current collector pieces (42) (4
2) PTC element between the corresponding second uncoated parts (45) and (45)
The second non-coated portion (45) and the PTC element (5) are joined with a conductive adhesive across the (5), and a plurality of current collector pieces (42)
Are connected to each other. Thereafter, the base end of the current collecting tab (3) is overlapped on the first uncoated portion (44) of each current collector piece (42), and laser welding is performed.
The current collecting tab (3) is joined by ultrasonic welding or the like.

A wound electrode body as shown in FIG. 6 was prepared in the same manner as in the prior art except that the positive electrode (4) thus produced was used.
(2) is prepared, and the wound electrode body (2) is accommodated in a battery can (1) as shown in FIG. 5 to complete a cylindrical lithium secondary battery.

Incidentally, as the PTC element (5), an element obtained by dispersing a conductive inorganic filler in a crosslinked product of a crystalline synthetic resin with a silane compound based crosslinking agent can be employed. Here, as the synthetic resin, high-density polyethylene, polypropylene, nylon, polyacetal, polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, polytetrafluoroethylene, polyethylene terephthalate, etc. are used, and as the conductive inorganic filler, , Carbon black, TiC, BC, CrC, ZrC, TiB, ZrN,
Powders such as TiN, Al, and Cu can be used, and vinylsilane, epoxysilane, aminosilane, mercaptosilane, and the like can be used as the silane compound-based crosslinking agent.

Next, the contents and results of an experiment conducted to confirm the performance of the cylindrical lithium secondary battery of the first embodiment will be described.

[0024]Experiment 1  A battery A of the present invention and a comparative battery X were prepared in the following manner.
Pond characteristics were measured. [Preparation of positive electrode] Positive electrode active material (LiCoO₂), Conductive agent (
Positive electrode consisting of carbon powder) and a binder (fluororesin powder)
The mixture was used as an aluminum foil (thickness 20) as a positive electrode current collector.
μm) on both sides by the doctor blade method.
After vacuum drying for 2 hours at 0 ° C., a positive electrode piece (width 50 m
m, length 500mm, uncoated part length 15mm)
Made.

[Preparation of Negative Electrode] A negative electrode mixture comprising a negative electrode material (graphite powder) and a binder (fluororesin powder) was applied to both surfaces of a copper foil (thickness: 20 μm) as a negative electrode current collector by a doctor blade method. Apply, apply vacuum drying at 150 ° C for 2 hours,
Negative electrode (width 55 mm, length 1600 mm, uncoated part length 5
mm).

[Production of PTC element] High density polyethylene
(60% by weight), carbon black (40% by weight) and a silane coupling agent (4 parts by weight) are kneaded, then formed into a sheet, cut into a width of 5 cm and a length of 15 mm.
A TC device was manufactured. Then, the PTC element was joined to the non-coated portion of the positive electrode by a conductive adhesive, and the three positive electrode pieces were connected to each other.

[Preparation of Electrolyte] An LiPF ₆ solute was dissolved in a mixed solvent of ethylene carbonate and diethyl carbonate to prepare an electrolyte.

[Assembly of Battery] A positive electrode and a negative electrode were spirally wound through a separator to prepare a wound electrode body. As the separator, a microporous membrane made of polypropylene having ion permeability was used. Then, the wound electrode body is inserted into the battery can, the positive electrode tab is welded to the positive terminal of the battery can, the negative electrode tab is welded to the negative terminal of the battery can, and after further injecting the electrolyte, the battery can is removed. After sealing, Battery A of the present invention was produced. In addition, a width of 50 mm with a PTC element layer (thickness of 20 μm) sandwiched between the positive electrode current collector and the electrode material,
A comparative battery X was prepared in the same manner as the battery A of the present invention except that a positive electrode having a length of 1500 mm was used.

[Measurement of Battery Characteristics] A charge / discharge test was performed under the conditions of a charge current of 50 mA, a charge end voltage of 4.1 V, a discharge current of 50 mA, and a discharge end voltage of 2.7 V, and a discharge capacity was measured.

Table 1 shows the results of comparing the discharge capacities of the conventional battery and the battery of the present invention.

[Table 1]

As is clear from the results in Table 1, the battery A of the present invention has a larger discharge capacity and better battery characteristics than the comparative battery X. This is because, in the battery of the present invention, the structure in which the plurality of divided electrode pieces are connected by the PTC element is adopted, so that the volume of the PTC element is smaller than that of the comparative battery, and the amount of the electrode material is reduced by the reduced amount. It is considered that the energy density increased and the energy density increased.

[0032]Experiment 2  Next, the number A of the current collector pieces constituting the positive electrode and the total length of the positive electrode
Consider the relationship between B and the length C of the PTC element.
Next, the following batteries B1 to B6 of the present invention were produced. That is, the length
Except for using two 75cm current collector pieces for the positive electrode
Battery B1 of the present invention was produced in the same manner as in battery A. Long
Except for using 5 pieces of 30 cm current collector as the positive electrode
Battery B2 of the invention was made in the same manner as Battery A of the invention.
Other than using 10 pieces of current collector pieces with a length of 15 cm for the positive electrode
Is a battery B3 of the present invention prepared in the same manner as the battery A of the present invention.
Was. The present invention except that a PTC element having a length of 1 cm is used.
Battery B4 of the invention was made in the same manner as Battery A. length
Battery A of the present invention was used except that a 2 cm PTC element was used.
Similarly, battery B5 of the invention was produced. 6cm long
Same as Battery A of the present invention except that a PTC element is used.
Thus, Battery B6 of the present invention was produced.

Table 2 shows the values of the parameters (A × C / B) and the measurement results of the discharge capacity of the batteries A and B1 to B6 of the present invention.

[Table 2]

As apparent from Table 2, the parameter (A ×
The discharge capacity is particularly large in a battery having C / B) smaller than 0.1.
It can be said that it is preferable to set C / B) smaller than 0.1.

[0035]

Second Embodiment In the secondary battery of this embodiment, as shown in FIG. 3, a positive electrode (6) has a strip-shaped current collector (61) which is long in the winding direction of a winding electrode body. An electrode material (62) applied to both surfaces of the current collector (61), and a PTC element (7) joined to an uncoated portion (63) of the current collector (61). PTC
The base of the current collecting tab (3) is joined to the surface of the element (7). In the manufacturing process of the positive electrode (6), the electrode material (6) is formed on the surface of the current collector (61) except for the joining region of the PTC element (7).
2) is applied to form uncoated portions (63) at a plurality of locations. Next, after the current collecting tab (3) and the PTC element (7) are joined to each other by ultrasonic welding or laser welding, they are joined to an electrode material (6).
It is joined to the uncoated part (63) of 2) by ultrasonic welding or laser welding. The negative electrode has the same configuration as the positive electrode (6) (not shown).

A wound electrode body (2) as shown in FIG. 6 was prepared in the same manner as in the prior art except that the thus prepared positive electrode and negative electrode were used. As shown in FIG. 5, the battery is accommodated in a battery can (1) to complete a cylindrical lithium secondary battery. As the PTC element (7), an element using a conductive polymer (synthetic resin), an element using ceramics, or the like can be employed.
C. is preferred. Here, the operating temperature refers to a temperature at which the resistance value reaches 1000 times that at room temperature due to a rise in temperature. The PTC element (7) preferably has a specific resistance of 10 Ω · cm or less at 20 ° C. It is preferable that the thickness of the PTC element (7) is in the range of 10 to 500 μm because the discharge capacity and the current interrupting property are excellent.

As the cathode material, various cathode materials conventionally used for non-aqueous batteries, such as a lithium-containing composite oxide (eg, LiCoO ₂ ), can be used. This positive electrode material is kneaded with a conductive agent such as acetylene black and carbon black and a binder such as polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVdF), and used as a positive electrode mixture. As the negative electrode material, metallic lithium, a lithium alloy, or a material such as a carbon material or a metal oxide which can be doped or dedoped with lithium can be used. As the electrolyte, various electrolytes conventionally used for lithium secondary batteries, such as lithium hexafluorophosphate, can be used. As the separator, various kinds of separators conventionally used for lithium secondary batteries, such as a microporous film made of polyethylene or polypropylene having excellent ion conductivity, can be used.

Next, the contents and results of an experiment conducted for confirming the performance of the cylindrical lithium secondary battery of the second embodiment will be described.

[0039]Experiment 1  A battery A1 of the present invention and a comparative battery X were prepared as follows.
Battery characteristics were measured. [Production of positive electrode] Lithium cobaltate as positive electrode material
(LiCoO₂) Powder and carbon powder as conductive agent
Polyvinylidene fluoride (PVdF) as an adhesive
The mixture was mixed at a ratio of 90: 5: 5 to obtain a positive electrode mixture. Next
Then, N-methyl-2-pyrrolidone was added to this positive electrode mixture.
Into a slurry, and use this as aluminum as the positive electrode current collector.
After rolling on the aluminum foil, roll and cut to 240mm width
Then, a positive electrode was produced.

[Preparation of Negative Electrode] Natural graphite powder as a negative electrode material and polyvinylidene fluoride (PVdF) as a binder
Were mixed at a weight ratio of 90:10 to obtain a negative electrode mixture. Next, N-methyl-2-pyrrolidone was added to this negative electrode mixture to form a slurry, which was applied to a copper foil as a negative electrode current collector, rolled, and further cut into a width of 250 mm to produce a negative electrode. did.

[Preparation of electrolyte solution] Ethylene carbonate
Lithium hexafluorophosphate as a solute was dissolved in an equal volume mixed solvent of (EC) and diethyl carbonate (DEC) at a ratio of 1 mol / liter to prepare an electrolytic solution.

[Assembly of Battery] The positive electrode current collector was
The PTC element of μm and the current collecting tab made of aluminum are overlapped, and the PTC element is brought into contact with the uncoated portion of the current collector,
These were joined using ultrasonic welding or the like. Similarly, a 100 μm-thick PTC element and a nickel current collecting tab were overlapped on the uncoated portion of the negative electrode current collector, and these were joined by ultrasonic welding or the like. In addition, the current collection tab is 1 for both the positive electrode and the negative electrode.
0 sheets were attached at equal intervals. In addition to the above-described positive electrode, negative electrode, and electrolyte, a separator made of a microporous thin film made of polypropylene or the like is used, and has a diameter of 60 mm and a height of 290 mm.
Inventive battery A1 was produced.

Also, a PTC having a thickness of 20 μm is formed on both sides of the current collector.
After attaching the element sheet, a positive and negative electrode mixture was applied to prepare a positive electrode and a negative electrode, and after attaching a current collecting tab to these electrodes, a comparative battery X was produced in the same manner as the battery A1 of the present invention. .

[Measurement of Battery Characteristics] With respect to the battery A1 of the present invention and the comparative battery X, the battery voltage was 4.2 at a current of 10 A.
After charging to V, the discharge capacity at the time of discharging to 2.7 V was measured. Table 3 shows the results.

[0045]

[Table 3]

As is clear from Table 3, the battery A1 of the present invention has a larger discharge capacity than the comparative battery X, which confirms the effectiveness of the battery of the present invention.

[0047]Experiment 2  In Experiment 2, the following batteries A2 to A6 of the present invention were prepared and
Influence of TC element thickness on battery discharge capacity
A study was conducted. The thickness of the PTC element was determined according to the battery A2 of the present invention.
10 μm, 50 μm for the battery A3 of the present invention, and
200 μm for pond A4, 500 μm for battery A5 of the present invention
m, except that the battery A6 of the present invention was changed to 1000 μm.
Are the batteries A2 to A6 of the invention in the same manner as the battery A1 of the invention.
Was prepared.

After charging each of the batteries A2 to A6 of the present invention to a battery voltage of 4.2 V with a current of 10 A,
The discharge capacity when discharging to 2.7 V was measured. Table 4 shows the results.

[0049]

[Table 4]

As is evident from Table 4, batteries having a PTC element thickness in the range of 10 μm to 500 μm are excellent in terms of discharge capacity, and a PTC element having a thickness of less than 10 μm can be manufactured. Since it is difficult, it is understood that it is preferable to form the thickness of the PTC element in this range. Further, it can be seen that it is more preferable that the thickness of the PTC element is formed in the range of 10 μm to 200 μm.

In both the first embodiment and the second embodiment, the volume occupied by the PTC element in the battery can is reduced as compared with the conventional battery, and the amount of the electrode material is increased accordingly. In addition, since a power loss due to the electric resistance of the PTC element is reduced, a large discharge capacity is achieved. For example, in the first embodiment, the discharge capacity of the comparative battery is 2.5 Ah, while the discharge capacity of the battery of the present invention is 3.5 Ah, and a 40% increase is achieved. In the second embodiment, the discharge capacity of the battery of the present invention was 70 Ah, whereas the discharge capacity of the comparative battery was 40 Ah.
A 5% increase has been achieved. This increase in discharge capacity
It is presumed that this is due to an increase in the electrode material and a decrease in power loss due to electrical resistance. In particular, it is estimated that as the electrode area increases, the effect of reducing power loss due to electrical resistance increases.

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, in the above embodiment, the present invention is applied to a cylindrical secondary battery. However, the present invention is not limited to this, and can be applied to nonaqueous electrolyte secondary batteries having various shapes such as a flat shape and a square shape. Of course.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a main part of a positive electrode employed in a battery according to a first embodiment of the present invention.

FIG. 2 is a perspective view illustrating a manufacturing process of the positive electrode.

FIG. 3 is a perspective view showing a main part of a positive electrode employed in a battery according to a second embodiment of the present invention.

FIG. 4 is a perspective view illustrating an appearance of a cylindrical secondary battery.

FIG. 5 is a cross-sectional view showing a main part of a cylindrical secondary battery.

FIG. 6 is an exploded perspective view showing a part of the wound electrode body.

FIG. 7 is a cross-sectional view of a positive electrode including a conventional PTC element layer.

[Explanation of symbols]

 (1) Battery can (2) Winding electrode body (3) Current collecting tab (4) Positive electrode (42) Current collector piece (43) Electrode material (44) Uncoated part (45) Uncoated part (5 ) PTC element (6) Positive electrode (61) Current collector (62) Electrode material (63) Uncoated part (7) PTC element

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takeshi Maeda 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Inventor Atsushi Funabashi 2-chome, Keihanhondori, Moriguchi-shi, Osaka No. 5 Sanyo Electric Co., Ltd. 2-5-5 Sanyo Electric Co., Ltd. (72) Inventor Koji Nishio 2-5-5 Keihan Hondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd.

Claims (5)

[Claims] 1. An electrode body (2) is housed inside a battery can (1), and power generated by the electrode body (2) can be taken out from an electrode terminal mechanism (9) attached to the battery can (1). In the non-aqueous electrolyte secondary battery formed by applying an electrode material on the surface of a belt-shaped current collector, at least one of the positive electrode and the negative electrode, The current collector of one of the electrodes has a plurality of current collector pieces (42) arranged along one direction and a positive temperature coefficient of resistance that connects adjacent current collector pieces (42) to each other. A non-aqueous electrolyte secondary battery characterized by comprising an element. 2. A pair of current collector pieces (42) (4) to be connected to each other.
2. The non-aqueous electrolyte secondary battery according to claim 1, wherein the end of (2) is vertically overlapped with the element interposed therebetween and joined to both surfaces of the element. 3. The relationship expressed by the following equation (1) between the number A of the current collector pieces (42), the total length B of the electrodes along the one direction, and the length C of the element. 3. The non-aqueous electrolyte secondary battery according to 2. ## EQU1 ## A × C / B <0.1 4. An electrode body (2) is housed inside a battery can (1), and power generated by the electrode body (2) can be taken out from an electrode terminal mechanism (9) attached to the battery can (1). The positive electrode and the negative electrode constituting the electrode body (2) are respectively coated on the surface of the strip-shaped current collector (61) with the electrode material (62) coated thereon and the electrode material (62). A non-coated portion that is not coated is formed, the base portion of the current collecting tab (3) is connected to the non-coated portion, and the tip of the current collecting tab (3) is connected to an electrode terminal mechanism ( 9) In the non-aqueous electrolyte secondary battery connected to 9), at least one of the positive electrode and the negative electrode is a non-coated portion of the current collector (61) and a base end of the current collection tab (3). A non-aqueous electrolyte secondary battery comprising an element having a positive temperature coefficient of resistance interposed between opposing surfaces of the non-aqueous electrolyte solution. 5. The device according to claim 1, wherein said device has a thickness of 10 μm to 500 μm.
The non-aqueous electrolyte secondary battery according to claim 4, wherein the secondary battery is formed in a range of m.