JPH09306471A - Nonaqueous electrolyte secondary battery and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery and its manufacturing method in which an inferiority factor can be decreased even when its capacity is heightened and high rate discharge is possible. SOLUTION: In both surfaces or one surface of a band-shaped positive electrode collector 11 formed of an aluminum substrate, except a region in both side edge parts, by coating a positive electrode mix layer 14 consisting of a lithium cobalt oxide, conductive agent and a binder, a bond-shaped positive electrode plate 1 having uncoated parts 12, 13 in both the side edge parts is formed. A plurality of positive electrode lead terminals are mounted by ultrasonic welding to the uncoated part 12 of the positive electrode collector 11. Ratio of a width W1 of the uncoated part 12 in a positive electrode lead terminal connection side relating to an electrode width L is set to 0.7% or more and 20% or less, a width W2 of the other uncoated part 13 is set to 0.5mm or more and 20mm or less.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a non-aqueous electrolyte secondary battery having a strip-shaped positive electrode plate and a strip-shaped negative electrode plate.

[0002]

2. Description of the Related Art Lithium secondary batteries (lithium ion secondary batteries) are used in various fields because they have a high energy density and are lightweight. Particularly, a lithium secondary battery used as a power source for a driving device, a portable electronic device, an electric vehicle, etc. is required to have a high rate discharge performance. Since the resistance of the non-aqueous electrolyte is significantly higher than that of the aqueous electrolyte, it is necessary to increase the area of the electrodes and increase the facing area in order to obtain high rate discharge performance. Therefore, a non-aqueous electrolyte lithium secondary battery requires an extremely thin strip electrode as compared with an electrode of an aqueous solution secondary battery.

9, FIG. 10 and FIG. 11 are views showing a method of manufacturing an electrode in a conventional lithium secondary battery. First, as shown in FIG. 9, a strip-shaped current collector 5 made of a metal foil.
The surface of No. 0 is intermittently coated with the electrode paste 52 in the form of slurry using the coating device 60, and then dried. An uncoated portion 51 is formed between the electrode pastes 52 on the current collector 50.

Next, as shown in FIG. 10, the band-shaped electrode plate is formed by cutting the current collector 50 into a predetermined width as shown by a broken line using a slitter. Then, as shown in FIG. 11, the lead terminal 53 is welded to the intermittent uncoated portion 51 of the current collector 50. The band-shaped positive electrode plate and the band-shaped negative electrode plate thus manufactured are wound or laminated with a separator interposed therebetween to assemble a power generation element.

[0005]

However, in a large lithium secondary battery used in an electric vehicle or the like, 100
~ High capacity of 400Wh class and 20 ~ 1000A
High rate discharge performance is required. To obtain such high rate discharge performance, 10 to 50 lead terminals are required. In the above method of welding the lead terminal to the intermittent uncoated portion of the current collector, if a plurality of uncoated portions are provided to weld a large number of lead terminals, the area of the uncoated portion relative to the area of the electrode plate However, there is a problem that the energy density of the battery is lowered. Therefore, it becomes difficult to obtain a high battery capacity.

Therefore, the present inventor has devised a method of manufacturing the electrode plate shown in FIGS. 12 and 13 in order to solve the above problem. As shown in FIG. 12, on the surface of the strip-shaped current collector 70,
By coating the mixture layer 73 except for the regions of both side edge portions, the uncoated portion 7 is applied to both side edge portions of the surface of the current collector 70.
1, 72 are formed. Then, the current collector 70 is cut with a slitter as shown by a broken line to separate one uncoated portion 72. Then, as shown in FIG. 13, a plurality of lead terminals 80 are attached to the uncoated portion 71 of the current collector 70 by welding. According to this method, a non-aqueous electrolyte secondary battery having a high capacity and capable of high rate discharge can be obtained.

However, if the electrode density is increased and the length of the electrode plate is increased in order to further increase the capacity, there arises a problem that the defective rate becomes higher than that of a conventional small battery. The present inventor has conducted various studies and experiments in order to investigate the cause of the increase in defective rate associated with higher capacity, and as a result, the following points have been found.

When the current collector 70 coated with the composite material layer 73 in order to improve the electrode density is pressed with a large pressure, the planar shape of the current collector 70 is slightly curved as shown in FIG. This has a thickness of 10 to 5 as the current collector 70.
Since a metal foil made of copper or aluminum, which is extremely thin and 0 mm, is used, the metal foil is rolled as shown by an arrow A in the coating portion of the composite material layer 73 when a pressing pressure is applied, and the metal foil is not coated. This is because the portion 71 is hardly rolled as indicated by arrow B. In this way, the current collector 7
Since 0 is slightly curved, when the curved current collector 70 is spirally wound around the winding core 81, as shown in FIG. As a result, an internal short circuit will occur.

Further, since the hardness of the current collector 70 and the hardness of the composite material layer 73 are different from each other, when the current collector 70 is cut together with the composite material layer 73 by a slitter at the time of manufacturing the electrode plate, the edge portion of the current collector 70 is cut off. A very thin whisker-shaped metal piece of 10 to 50 μm may occur. When such a beard-shaped metal piece is generated, an internal short circuit may occur. In a small-capacity secondary battery, since the electrode length (length of the strip-shaped electrode plate) is as short as about 50 cm, the occurrence rate of whisker-like metal pieces is low, and the defective rate is about 0.1 to 0.5%. do not become. On the other hand, in a high-capacity secondary battery having an electrode length of 10 to 20 m, a whisker-like metal piece is highly likely to be generated, and the defective rate is as large as 2 to 20%.

As described above, if the electrode density is increased and the length of the electrode plate is increased in order to increase the capacity, there is a problem that the defective rate due to an internal short circuit increases. An object of the present invention is to provide a non-aqueous electrolyte secondary battery which has a low defect rate even when the capacity is increased and which can be discharged at a high rate, and a manufacturing method thereof.

[0011]

Means for Solving the Problems and Effects of the Invention A non-aqueous electrolyte secondary battery according to the present invention has a strip-shaped electrode plate in which a mixture layer is formed on a strip-shaped current collector. In the above, the mixture layer is formed on the surface of the current collector except for both side edge regions.

In the non-aqueous electrolyte secondary battery according to the present invention, the area where the mixture layer is not formed is formed on both side edges of the surface of the current collector. Therefore, even if the strip electrode plate is pressed to improve the electrode density, the planar shape of the strip electrode plate does not curve. Further, since the current collector can be cut in the region where the composite material layer is not formed, whiskers of metal pieces are not generated at the edge of the current collector. Therefore, even if the electrode density is increased to increase the capacity and the length of the strip electrode plate is increased, the defect rate due to the internal short circuit can be kept low.

In particular, it is preferable that one or a plurality of lead terminals be attached to at least one side edge portion of the current collector in a region where the composite material layer is not formed. This makes it possible to increase the number or area of the lead terminals while keeping the area of the composite material layer large with respect to the area of the strip electrode plate. Therefore, high capacity and high rate discharge are possible.

Further, the ratio of the width of the unformed region in at least one side edge portion to the width of the current collector is preferably 0.7% or more and 20% or less. Thereby, the attachment strength of the lead terminals can be secured and a high battery capacity can be obtained.

Further, one or a plurality of lead terminals are attached to an area where the composite material layer is not formed on one side edge portion of the current collector, and an area where the composite material layer is not formed on the other side edge portion of the current collector. The width is preferably 0.5 mm or more and 20 mm or less. As a result, it is possible to prevent the bending of the strip electrode plate during pressing and the generation of whiskers of metal pieces during cutting of the current collector, and to secure a high battery capacity.

The structure of the strip electrode plate may be possessed by either one of the strip positive electrode plate and the strip negative electrode plate, or both of them. However, it is preferable that both the strip-shaped positive electrode plate and the strip-shaped negative electrode plate have the above structure. As a result, it is possible to effectively reduce the defective rate and effectively ensure high capacity and high rate discharge.

A strip-shaped positive electrode plate in which a positive electrode mixture layer is formed on a strip-shaped positive electrode collector and a strip negative electrode plate in which a negative electrode mixture layer is formed on a strip-shaped negative electrode collector are wound or laminated with a separator in between. In the non-aqueous electrolyte secondary battery thus formed, the positive electrode mixture layer is formed on the surface of the positive electrode current collector except for the regions of both side edges, and the surface of both sides of the negative electrode current collector is formed. The negative electrode mixture layer may be formed except the region.

In this case, even if the strip-shaped positive electrode plate and the strip-shaped negative electrode plate are pressed to improve the electrode density, the planar shapes of the strip-shaped positive electrode plate and the strip-shaped negative electrode plate are not curved. Further, since the current collector can be cut in the area where the composite material layer is not formed,
No whisker-like metal pieces are generated on the edges of the current collector. Therefore, a high capacity non-aqueous electrolyte secondary battery with a low defective rate due to an internal short circuit can be obtained.

The method for producing a non-aqueous electrolyte secondary battery according to the present invention is a method for producing a non-aqueous electrolyte secondary battery having a strip-shaped electrode plate in which a mixture layer is formed on a strip-shaped collector. The mixture layer is formed on the surface of the body in a width narrower than that of the current collector except for the regions on both side edges.

In the manufacturing method according to the present invention, since the region where the composite material layer is not formed exists on both side edges of the surface of the current collector, the strip electrode plate is pressed to improve the electrode density. Also, the planar shape of the strip electrode plate is not curved. Further, since the current collector can be cut in the region where the composite material layer is not formed, whiskers of metal pieces are not generated at the edge of the current collector. Therefore, it is possible to obtain a high capacity non-aqueous electrolyte secondary battery having a low defective rate due to an internal short circuit.

In particular, the strip-shaped electrode plate may be formed by forming a plurality of composite material layers on the current collector in a stripe shape and then cutting the current collector at a region where the composite material layer is not formed. in this case,
It is possible to efficiently manufacture a plurality of strip electrode plates.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION A lithium secondary battery and a method of manufacturing the same according to an embodiment of the present invention will be described below with reference to FIGS.

First, in FIG. 3, the strip-shaped positive electrode plate 1 has a lithium cobalt composite oxide (LiCoO ₂ ) together with a conductive agent on one or both sides of a positive electrode current collector made of an aluminum substrate (aluminum foil) having a thickness of 20 μm. It is held by using a binder. The belt-shaped positive electrode plate 1 has a thickness of 190 μm and a width of 165 mm, for example.

The strip-shaped negative electrode plate 3 is obtained by holding graphite on one or both sides of a negative electrode current collector made of a copper substrate (copper foil) having a thickness of 18 μm using a binder. The strip-shaped negative electrode plate 3 has a thickness of, for example, 160 μm and a width of, for example, 169 mm.
It is.

The separator 2 is formed of a polyethylene microporous film. The separator 2 has a thickness of 25 μm and a width of 173 mm, for example. Here, a method for manufacturing the strip-shaped positive electrode plate 1 will be described with reference to FIGS. 1 and 2. First, as shown in FIG. 1, on the surface of the positive electrode current collector 11 made of an aluminum substrate, a positive electrode mixture layer composed of a lithium cobalt composite oxide, a conductive agent and a binder except for the regions at both side edges. 14 is applied using a coating device. As a result, the uncoated portions 12 and 13 having a constant width are formed on both side edge portions of the surface of the positive electrode current collector 11, respectively. In the uncoated parts 12 and 13, the positive electrode current collector 11
Is exposed. The width of one uncoated portion 12 is W1, and the width of the other uncoated portion 13 is W2. The width (electrode width) of the strip-shaped positive electrode plate 1 is L.

Next, as shown in FIG. 2, the positive electrode current collector 11
A plurality of positive electrode lead terminals 4 are attached to the uncoated part 12 by ultrasonic welding. In this way, the strip-shaped positive electrode plate 1 is manufactured.

If the width W1 of the uncoated portion 12 is smaller than 0.7% of the electrode width L, the welding strength of the positive electrode lead terminal 4 becomes weak, so that the positive electrode lead terminal 4 may come off during battery assembly. It causes trouble. On the other hand, the width W1 of the uncoated portion 12
When exceeds 20% of the electrode plate L, the battery capacity decreases.
Therefore, W1 of the uncoated portion 12 is 0.7 of the electrode width L.
% To 20% is preferable.

The width W2 of the uncoated portion 13 is 0.5 mm.
If it is smaller than the above range, the strip-shaped positive electrode plate 1 is likely to be bent during pressing, so that the strip-shaped positive electrode plate 1 is misaligned during battery assembly. On the other hand, when the width W2 of the uncoated portion 13 exceeds 20 mm, the battery capacity decreases. Therefore, the uncoated part 1
The width W2 of 3 is preferably 0.5 mm to 20 mm.

The method for manufacturing the strip negative electrode plate 3 is the same as the manufacturing method shown in FIGS. In FIG.
A plurality of positive electrode lead terminals 4 are attached to the uncoated portion of the positive electrode current collector of the strip positive electrode plate 1 as described above, and a plurality of uncoated portions of the negative electrode collector of the strip negative electrode plate 3 are The negative electrode lead terminal 5 is attached. These strip-shaped positive electrode plate 1 and strip-shaped negative electrode plate 3 are superposed with a separator 2 in between,
A cylindrical electrode group is produced by spirally winding the core 6 made of an aluminum pipe.
This electrode group serves as a power generating element.

Next, as shown in FIG. 4, the outer peripheral portion of the cylindrical electrode group is fixed with tape 7 and crushed to form an electrode group having an oval cross section. After that, the electrode group is housed in a battery container (not shown) having an oval cross section and double-fastened and sealed. The dimensions of the battery container are, for example, 50 mm in length, 130 mm in width and 210 mm in height.
And the battery capacity is 100 Ah. Positive electrode lead terminal 4
The negative electrode lead terminal 5 is connected to the positive electrode terminal and the negative electrode terminal provided on the battery container.

Then, in this battery container, an electrolytic solution prepared by dissolving 1 mol / l (liter) of lithium hexafluorophosphate (LiPF ₆ ) in a mixed solution of ethylene carbonate and dimethyl carbonate at a ratio of 1: 1 (volume ratio) was placed. Inject under reduced pressure.

Here, the widths W1 and W2 of the uncoated portions 12 and 13 of the strip-shaped positive electrode plate 1 according to the methods and conditions shown in FIGS.
20 lithium secondary batteries having different characteristics were produced. The lithium secondary battery thus manufactured is
After being charged with a constant current of 0 A and a constant voltage of 4.2 V for 8 hours, the battery was discharged with a constant current of 20 A to 2.75 V. Then, the relationship between the ratio (W1 / L) of the width W1 of the uncoated portion 12 (positive electrode lead terminal connection portion) to the electrode width L, the number of defects in 20 lithium secondary batteries, and the discharge capacity was measured. The results of this measurement are shown in Table 1.

[0033]

[Table 1]

As shown in Table 1, when W1 / L is 0.7% or more and 20% or less, the number of defects is relatively small and a relatively high discharge capacity can be obtained. In particular, W1
When / L is 1% or more and 10% or less, the number of defects is extremely small and a higher discharge capacity can be obtained. W1 / L is 0.5
%, The discharge capacity is high, but the number of defects is large. It is considered that this is due to the detachment of the welded portion of the positive electrode lead terminal 4 when assembling the battery. Also, W1 / L is 3
At 0%, the number of defects is small, but the discharge capacity is low. Therefore, the width W of the uncoated portion 12 with respect to the electrode width L
The ratio of 1 is preferably 0.7% or more and 20% or less, more preferably 1% or more and 10% or less.

The ratio of the width W1 of one uncoated portion (negative electrode lead terminal connecting portion) of the negative electrode mixture layer to the electrode width L of the strip negative electrode plate 3 is 0.7 as in the strip positive electrode plate 1. % Or more and 20% or less are preferable, and 1% or more and 10% or less are more preferable.

Next, the relationship between the width W2 of the uncoated portion 13 (the portion to which the positive electrode lead terminal is not connected), the number of defects in 20 lithium secondary batteries, and the discharge capacity was measured. When the strip-shaped positive electrode plate 1 is manufactured, in order to increase the capacity of the battery, a lithium cobalt composite oxide (LiCoO 2) is formed on the surface of the positive electrode current collector 11.
₂ ), after applying the positive electrode mixture layer 14 composed of a conductive agent and a binder, 1 by a hot roll press at a temperature of 150 ° C.
Pressurized with 0 ton. Thereby, the porosity of the positive electrode mixture layer 14 was set to 40% or less, and the electrode density was improved. In this case, the ratio of the width W1 of the uncoated portion 12 to the electrode width L (W
1 / L) is 5%. The measurement results are shown in Table 2.

[0037]

[Table 2]

As shown in Table 2, it can be seen that when W2 is 0.5 mm or more and 20 mm or less, the number of defects is relatively small and a relatively high discharge capacity can be obtained. Especially W2
Is 1.0 mm or more and 10 mm or less, the number of defects is extremely small and a higher discharge capacity can be obtained. W2 is 0.2
When it is mm, the discharge capacity is high, but the number of defects is large. It is considered that this is due to winding deviation due to the curvature of the strip-shaped positive electrode plate 1 at the time of hot roll pressing or burrs (whisker-shaped metal pieces) at the time of cutting the positive electrode current collector 11. When W2 is 30 mm, the number of defects is small, but the discharge capacity is low. Therefore, the width W2 of the uncoated portion 13
Is preferably 0.5 mm or more and 20 mm or less, 1.0 m
It is more preferably m or more and 10 mm or less.

The width W2 of the other uncoated portion (non-negative electrode lead terminal non-connecting portion) of the negative electrode mixture layer of the strip negative electrode plate 3 is preferably 0.5 mm or more and 20 mm or less as in the strip positive electrode plate 1. , 1.0 mm or more and 10 mm or less are more preferable.

As described above, in the lithium secondary battery of this embodiment, the positive electrode composite material layer and the negative electrode composite material layer are not coated on both side edges of the surfaces of the strip positive electrode plate 1 and the strip negative electrode plate 3, respectively. The width W1 of the uncoated portion on the lead terminal connection side with respect to the electrode width L is set to 0.7% or more and 20% or less, and the width W2 of the other uncoated portion is 0.5 mm or more. By setting it to 20 mm or less, the defect rate is small,
High capacity and high rate discharge are possible.

FIG. 5 is a diagram showing another example of a method of manufacturing the strip positive electrode plate 1. In the example of FIG. 5, the positive electrode mixture layer 14 is applied in a plurality of stripes on both surfaces or one surface of the positive electrode current collector 11. As a result, the uncoated portions 12 and 13 are formed on both side edges of the positive electrode current collector 11, and the uncoated portions 12 a and 12 b are formed between the positive electrode mixture layers 14. Thereafter, the positive electrode current collector 11 is uncoated with a slitter 12 as shown by a broken line.
Cut at a and 12b. According to this method, a plurality of strip-shaped positive electrode plates 1 can be efficiently manufactured, and mass productivity is excellent. The strip negative electrode plate 3 can be manufactured in the same manner.

In the above embodiment, the positive electrode lead terminal 4 is used.
6 is attached to one uncoated portion 12 of the positive electrode current collector 11, but the positive electrode lead terminals 4 are formed on both side edge portions of the positive electrode current collector 11 as shown in FIG. 6A. Uncoated part 12
May be attached to. In this case, it is preferable to set the width W1 of the uncoated portions 12 on both side edge portions in the same manner as in the above embodiment. Similarly, the negative electrode lead terminal 5 may be attached to the uncoated portions formed on both side edges of the negative electrode current collector. In this case, as shown in FIG. 6B, the positive electrode lead terminal 4 and the negative electrode lead terminal 5 are provided at both ends of the electrode group.

In the above embodiment, the electrode group is formed in a shape having an oval cross section, but the shape of the electrode group is not limited to this, and as shown in FIG. It may be shaped. Alternatively, as shown in FIG. 7B, the electrode group may be formed into a rectangular shape by stacking the strip-shaped positive electrode plate and the strip-shaped negative electrode plate so as to be stacked and folded so as to be folded.

The shapes and welding methods of the positive electrode lead terminal and the negative electrode lead terminal are not limited to those in the above embodiment.
For example, as shown in FIG. 8, for example, a cross-shaped positive electrode lead terminal 4 is welded to one end surface of the strip-shaped positive electrode plate 1 on the uncoated portion side, and the other end surface of the strip-shaped negative electrode plate 3 on the uncoated portion side is welded. Alternatively, for example, a cross-shaped negative electrode lead terminal 5 may be welded. The shapes of the positive electrode lead terminal 4 and the negative electrode lead terminal 5 may be other shapes.

Further, the positive electrode mixture layer and the negative electrode mixture layer are
It is not limited to the above embodiment. As the positive electrode mixture layer, in addition to lithium cobalt composite oxide (LiCoO ₂ ), titanium disulfide, manganese dioxide, lithium nickel composite oxide, spinel type lithium manganese oxide, vanadium pentoxide, molybdenum trioxide, etc. are used. Various mix layers can be used, including: As the negative electrode mixture layer, various mixture layers including a graphite material, a low crystalline carbon material, an amorphous carbon material, a metal oxide, etc. can be used.

The present invention can be applied not only to the lithium secondary battery but also to various non-aqueous electrolyte secondary batteries.

[Brief description of drawings]

FIG. 1 is a plan view showing a first manufacturing process of a strip-shaped positive electrode plate of a lithium secondary battery in an example of the present invention.

FIG. 2 is a plan view showing a second manufacturing process of the strip-shaped positive electrode plate of the lithium secondary battery in one example of the present invention.

FIG. 3 is an exploded perspective view of an electrode group of a lithium secondary battery according to an embodiment of the present invention.

FIG. 4 is a perspective view of an electrode group of a lithium secondary battery according to an embodiment of the present invention.

FIG. 5 is a plan view showing another example of a method for manufacturing a strip positive electrode plate.

FIG. 6 is a diagram showing another example of a method of attaching the positive electrode lead terminal and the negative electrode lead terminal.

FIG. 7 is a perspective view showing another example of the shape of the electrode group.

FIG. 8 is a perspective view showing another example of the positive electrode lead terminal and the negative electrode lead terminal.

FIG. 9 shows a first electrode plate of a conventional lithium secondary battery.
FIG. 6 is a perspective view showing a manufacturing process of.

FIG. 10 is a plan view showing a second manufacturing process of an electrode plate in a conventional lithium secondary battery.

FIG. 11 is a plan view showing a third manufacturing process of an electrode plate in a conventional lithium secondary battery.

FIG. 12 is a plan view showing a first manufacturing process of a strip electrode plate of a lithium secondary battery according to another invention of the present inventor.

FIG. 13 is a plan view showing a second manufacturing process of a strip electrode plate of a lithium secondary battery according to another invention of the present inventor.

FIG. 14 is a plan view showing the bending of the strip electrode plate by pressing.

FIG. 15 is a perspective view showing a winding deviation when the strip electrode plate of FIG. 14 is wound.

[Explanation of reference symbols] 1 strip positive electrode plate 2 separator 3 strip negative electrode plate 4 positive electrode lead terminal 5 negative electrode lead terminal 11 positive electrode current collector 12, 13 uncoated portion 14 positive electrode mixture layer

Claims (7)

[Claims] 1. A non-aqueous electrolyte secondary battery having a strip-shaped electrode plate in which a mixture layer is formed on a strip-shaped current collector, wherein the surface of the current collector is excluding both side edge regions. A non-aqueous electrolyte secondary battery having a mixture layer formed. 2. The non-aqueous electrolyte according to claim 1, wherein one or a plurality of lead terminals are connected to an area where at least one side edge of the current collector is not formed with the composite material layer. Next battery. 3. The ratio of the width of the region where the mixture layer is not formed in the at least one side edge portion to the width of the current collector is 0.7% or more and 20% or less. 2. The non-aqueous electrolyte secondary battery described in 2. 4. The one or more lead terminals are connected to the unformed region of the one side edge portion of the current collector, and the one or more lead terminals are connected to the other side edge portion of the current collector. The non-aqueous electrolyte secondary battery according to claim 1, 2 or 3, wherein the width of the unformed region is 0.5 mm or more and 20 mm or less. 5. A strip-shaped positive electrode plate in which a positive electrode mixture layer is formed on a strip-shaped positive electrode collector and a strip negative electrode plate in which a negative electrode mixture layer is formed on a strip-shaped negative electrode collector are wound with a separator interposed therebetween. Alternatively, in a non-aqueous electrolyte secondary battery formed by stacking, the positive electrode mixture layer is formed on the surface of the positive electrode current collector except for both side edge regions, and both are formed on the surface of the negative electrode current collector. The non-aqueous electrolyte secondary battery in which the negative electrode mixture layer is formed except for the side edge region. 6. A method for manufacturing a non-aqueous electrolyte secondary battery having a strip-shaped electrode plate in which a mixture layer is formed on a strip-shaped current collector, wherein both side edge regions are provided on the surface of the current collector. A method for manufacturing a non-aqueous electrolyte secondary battery, characterized in that the mixture layer is formed in a width narrower than that of the current collector. 7. The strip-shaped electrode plate is formed by forming a plurality of composite material layers on a current collector in a stripe shape and then cutting the current collector at a region where the composite material layer is not formed. The method for producing a non-aqueous electrolyte secondary battery according to claim 6.