JP2004111300A - Non-aqueous electrolyte secondary battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a non-aqueous electrolyte secondary battery that can radiate to the outside, heat generated in the positive electrode 1a of a generating element 1 by efficiently conducting it to the lid plate of aluminum alloy and the battery container 9. <P>SOLUTION: This is a non-aqueous electrolyte secondary battery in which the generating element 1 in which a positive electrode 1a and a negative electrode 1b are wound via a separator 1c is housed in a battery container 9 made of aluminum alloy, and the upper end opening part of this battery container 9 is covered by a lid plate 4. The positive electrode 1a wound by the generating element 1 is connected and fixed to a connecting plate part 2b of a current collector connecting plate 2 at plural parts on the inner and outer circumference of winding of the positive electrode 1a, and the main body 2c of this current collector connecting plate 2 is adhered to the inner face of the lid plate 4 and connected and fixed to the lid plate 4 by caulking of the terminal 5. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a nonaqueous electrolyte secondary battery in which a power generation element in which a positive electrode and a negative electrode are wound via a separator is housed in a metal battery case.
[0002]
[Prior art]
Until now, non-aqueous electrolyte secondary batteries generally used a lithium-cobalt-based composite oxide or a lithium-manganese-based composite oxide as a lithium-containing composite oxide as a positive electrode active material. However, recently, in order to further increase the energy density, use of a lithium-nickel-cobalt-based composite oxide has been studied. Comparing the energy per unit weight (energy density) of these lithium-containing composite oxides, the energy density of the lithium-manganese composite oxide is the smallest, and then the energy density of the lithium-cobalt composite oxide is Is slightly larger, and the energy density of the lithium-nickel-cobalt-based composite oxide is sufficiently higher than these.
[0003]
[Problems to be solved by the invention]
However, this lithium-nickel-cobalt-based composite oxide has a disadvantage that it is inferior in thermal stability to lithium-cobalt-based composite oxide and lithium-manganese-based composite oxide. That is, since the lithium-nickel-cobalt-based composite oxide has the lowest exothermic onset temperature and the largest calorific value among these lithium-containing composite oxides, when used as a positive electrode active material, the nonaqueous electrolyte When the secondary battery is short-circuited or overcharged, thermal runaway easily occurs. For this reason, in addition to making improvements to improve the thermal stability of the lithium-nickel-cobalt-based composite oxide material itself, use a structure that efficiently discharges heat from the positive electrode in the power generation element to the outside of the battery. Therefore, there is a problem that it is necessary to prevent the occurrence of thermal runaway.
[0004]
The demand for efficient heat dissipation is not limited to the case where a lithium-nickel-cobalt-based composite oxide is used as the positive electrode active material to increase the energy density, but also to other nonaqueous electrolyte secondary batteries. Is also common, and heat dissipation is not limited to the positive electrode.
[0005]
The present invention has been made in order to cope with such circumstances, and a non-aqueous electrolyte secondary battery capable of efficiently transmitting heat generated at an electrode of a power generating element to a metal battery case and releasing the heat to the outside. It is intended to provide.
[0006]
[Means for Solving the Problems]
The invention according to claim 1 is a non-aqueous electrolyte secondary battery in which a power generating element in which a positive electrode and a negative electrode are wound via a separator is housed in a metal battery case. The electrode directly contacts the inner surface of the battery case, and a part or all of the contact portion is connected and fixed to the inner surface of the battery case by welding.
[0007]
According to the first aspect of the present invention, since the outermost electrode of the power generating element is in contact with the battery case and is fixedly connected thereto, the heat generated at this electrode is directly transmitted to the metal battery case, and a large area is generated. It is efficiently released to the outside. Therefore, the battery case actively serves as a heat sink, and it is possible to prevent the battery from becoming abnormally high temperature due to the heat generated by the electrodes. In addition, when the battery case swells due to an increase in internal pressure due to the use of the battery, if the outermost electrode of the power generating element simply contacts the inner surface of the battery case, the electrode is separated from the inner surface of the battery case. There is a risk. However, according to the first aspect of the present invention, the outermost electrode of the power generation element not only comes into contact with the inner surface of the battery case but also is securely connected and fixed by welding. Are not separated, and the heat generated by the electrodes can be reliably radiated from the battery case.
[0008]
Since the metal battery case functions as a terminal having the polarity of an electrode connected and fixed to the inner surface, it is not always necessary to use a current collector connected between the electrode and the terminal. However, in the case of a large non-aqueous electrolyte secondary battery, current collection only from the outermost periphery of the electrode causes the internal resistance to be too large. It is also preferable to collect current.
[0009]
In a non-aqueous electrolyte secondary battery in which a power generation element in which a positive electrode and a negative electrode are wound via a separator is housed in a metal battery case, any one of positive and negative electrodes wound around the power generation element is provided. Are connected and fixed to the current collecting connector at a plurality of locations on the inner and outer circumferences of the winding of the electrode, and the current collecting connector is connected and fixed to the inner surface of the battery case, or a terminal connected and fixed to the battery case. Is fixedly connected.
[0010]
According to the second aspect of the present invention, since a plurality of locations on the inner and outer peripheries of the electrodes of the power generating element are connected and fixed to the battery case via the current collectors and the terminals, the heat generated at the electrodes is efficiently made of metal. The battery case is transmitted to the outside from a large area. Therefore, the battery case actively serves as a heat sink, and it is possible to prevent the battery from becoming abnormally high temperature due to the heat generated by the electrodes.
[0011]
According to the second aspect of the present invention, the electrodes connected and fixed to the current collector at a plurality of locations on the inner and outer circumferences of the winding are wound around the outermost circumference of the power generating element, and the outermost electrodes are mounted on the inner surface of the battery case. It can also be stored so as to make direct contact. In this case, not only are the electrodes of the power generating element connected and fixed to the battery case via the current collectors and terminals, but also the electrode wound on the outermost periphery comes into direct contact with the battery case. The heat generated in the above is directly transmitted to the metal battery case, so that the heat radiation efficiency can be further improved. Moreover, it is preferable that at least a part of the outermost electrode is connected and fixed to the inner surface of the battery case by welding. With this configuration, the electrode wound around the outermost periphery of the power generating element not only comes into contact with the battery case but also is fixedly connected to the battery case, so that the heat radiation efficiency can be further improved. In addition, when the battery case swells due to an increase in internal pressure due to the use of the battery, if the outermost electrode of the power generating element simply contacts the inner surface of the battery case, the electrode is separated from the inner surface of the battery case. There is a risk. However, if the outermost electrode of the power generation element is connected and fixed to the inner surface of the battery case, even if the battery case swells, the electrodes will not separate, and the heat generated by this electrode will be lost. Heat can be reliably dissipated from the battery case.
[0012]
In the first or second aspect, as shown in the prior art, a positive electrode using a lithium-nickel-cobalt-based composite oxide having particularly low thermal stability as a positive electrode active material is directly connected and fixed to a battery case. It is preferable to connect and fix the battery case to the battery case via an electrical connector or a terminal. When such a positive electrode active material is used, it is preferable to use a carbon material as the negative electrode active material of the negative electrode.
[0013]
In the above claim 1 or 2, when the electrode is one in which an active material is carried on the surface of a current collecting base material such as a metal foil, the active material is used in order to further improve the thermal conductivity. It is preferable that the surface portion of the current collecting base material that is not carried is brought into contact with the inner surface of the battery case and fixedly connected thereto, and that the exposed portion of the current collecting base material is fixedly connected to the current collecting connector. Is preferred.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0015]
1 and 2 show an embodiment of the present invention. FIG. 1 is an assembled perspective view showing a structure of a non-aqueous electrolyte secondary battery. FIG. 2 is an electrode of a power generating element of the non-aqueous electrolyte secondary battery. FIG. 3 is an assembled perspective view showing a connection structure between a power supply connection plate and a terminal.
[0016]
In this embodiment, a large non-aqueous electrolyte secondary battery used for an EV (electric vehicle) or the like will be described. As shown in FIG. 2, the nonaqueous electrolyte secondary battery is configured by arranging two long cylindrical wound-type power generating elements 1 and 1 in parallel. Each power generating element 1 is obtained by winding a positive electrode 1a and a negative electrode 1b in a long cylindrical shape via a separator 1c. The positive electrode 1a has a positive electrode active material carried on the surface of a belt-like aluminum foil, and the negative electrode 1b has a belt-like shape. The negative electrode active material is supported on the surface of a copper foil.
[0017]
As the positive electrode active material of the positive electrode 1a, a lithium-nickel-cobalt-based composite oxide is used in order to increase the energy density. However, since the positive electrode active material using the lithium-nickel-cobalt-based composite oxide generally has lower thermal stability than that using the lithium-cobalt-based composite oxide or the like, magnesium (Mg), aluminum (Al) ), Manganese (Mn), titanium (Ti), tungsten (W), boron (Mo) or niobium (Nb) to improve the thermal stability. Actually, when the lithium-nickel-cobalt-based composite oxide to which these elements are added is inspected by scanning differential thermal analysis (DSC), it can be confirmed that the heat generation start time is shifted to a high temperature side and the heat generation can be suppressed. In addition, the greater the amount of the element to be added, the more the thermal stability is improved, but on the contrary, the energy density, which is the original purpose, is reduced. Must be determined. That is, in the present embodiment, the general formula of the lithium (Li) / nickel (Ni) / cobalt (Co) -based composite oxide is Li _a Ni _b Co _c M _d O _2.
In this case, the element M is at least one element selected from Mg, Al, Mn, Ti, W, Mo, B, and Nb.
0 ≦ a ≦ 1.1
O. 7 ≦ b ≦ 0.9
0.1 ≦ c ≦ 0.3
0.03 ≦ d ≦ 0.1 (addition amount of element M)
(However, b + c + d = 1)
Within the range.
[0018]
As the negative electrode active material of the negative electrode 1b, a carbon material is used. Each of the positive electrode 1a and the negative electrode 1b is provided with an uncoated portion to which the active material is not applied at a band-shaped side end, and an aluminum foil or a copper foil is exposed at the uncoated portion. When the positive electrode 1a and the negative electrode 1b are wound, the uncoated portions of the active material are arranged in opposite directions in the winding axis direction. The aluminum foil at the side end of the positive electrode 1a protrudes from the end face of one of the long cylindrical shapes (lower right in the figure) and the other (upper left in the figure) Only the copper foil on the side end of the negative electrode 1b protrudes from the end surface of the negative electrode 1b. In the present embodiment, since the separator 1c is wound around the outermost periphery of the power generation element 1, these aluminum foils and copper foils protrude from both side ends of the separator 1c.
[0019]
The two power generating elements 1 and 1 are arranged side by side so that the long side surfaces of the long cylindrical shape are upright and overlap each other. Then, current collecting connection plates 2 and 2 are arranged at both ends of these two power generating elements 1 and 1, respectively. The collector connection plates 2 and 2 are arranged at one end of the power generating element 1 on the positive electrode side of an aluminum alloy plate, and arranged on the other end of the power generation element 1 on a negative electrode side of a copper alloy plate. Each of the current collecting connecting plates 2 has a substantially trapezoidal horizontally arranged main body 2a and four elongated connecting plate portions projecting downward from the bottom of the trapezoidal shape of the main body 2a in a comb shape. 2b. Each of the power generating elements 1 divides a straight portion of the aluminum foil of the positive electrode 1a protruding from one end face into a long cylindrical shape into two right and left parts around the winding axis and overlaps the divided aluminum foils. The aluminum foil of the positive electrode 1a is connected and fixed to the connection plate portion 2b by sandwiching the both sides with the holding plate 3 along the connecting plate portion 2b and performing ultrasonic welding from both sides of the holding plate 3. Therefore, the positive electrode 1a wound around each power generating element 1 is connected and fixed to the connecting plate portion 2b of the current collecting connecting plate 2 for each half circumference of the aluminum foil protruding from one end face at both straight portions of the long cylindrical shape. Will be. Similarly, the copper foil of the negative electrode 1b protruding from the other end face of each power generating element 1 into a long cylindrical shape is similarly sandwiched by the sandwiching plate 3 and connected and fixed to the connection plate portion 2b by ultrasonic welding. Therefore, the negative electrode 1b wound around each power generating element 1 is also connected and fixed to the connecting plate portion 2b of the current collecting connecting plate 2 for each half circumference of the copper foil protruding from the other end face at both straight portions of the long cylindrical shape. Will be.
[0020]
As shown in FIG. 1, the current collecting connecting plates 2 and 2 disposed at both ends of the two power generating elements 1 and 1 are connected to the main bodies 2a and 2a via the lid plate 4 with the positive terminal 5 and the negative terminal 6 respectively. Is fixedly connected. The lid plate 4 is a rectangular aluminum alloy plate, and the lower end of the positive electrode terminal 5 is in contact with the lid plate 4 and the main body 2a in a state where the main body 2a of the current collector connection plate 2 on the positive electrode side is in close contact with the lower surface of one end. Connection is fixed by penetrating from above from 2a and caulking from below. Therefore, the positive electrodes 1a, 1a of the power generation elements 1, 1 are connected and fixed to the positive electrode terminal 5 via one current collector connection plate 2, and are also connected and fixed to the cover plate 4. At the other end of the cover plate 4, a negative electrode terminal 6 is sealed and penetrated through a ceramic ring 7 to be insulated and fixed, and on the lower surface of the current collector connection plate 2 via an insulating plate 8. 2a is arranged. The lower end of the negative electrode terminal 6 projecting below the cover plate 4 penetrates the insulating plate 8 and the main body 2a and is caulked from below to be connected and fixed. Therefore, the negative electrodes 1 b and 1 b of the power generating elements 1 and 1 are connected and fixed to the negative electrode terminal 6 via the other current collecting connection plate 2, but the space between the negative electrode 1 b and the cover plate 4 is formed by the ceramic ring 7 and the insulating plate 8. It will be insulated. The work of caulking the lower ends of the positive and negative terminals 5 and 6 to the main bodies 2a and 2a of the current collecting connection plates 2 and 2 via the cover plate 4 is performed by connecting the current collecting connection plates 2 and 2 to each other. This is performed before the step of connecting and fixing the positive electrode 1a and the metal foil of the negative electrode 1b of the power generating elements 1 and 1 to the portion 2b.
[0021]
The power generating elements 1, 1 attached below the cover plate 4 by the current collecting connection plates 2, 2 and the terminals 5, 6 as described above are housed in a housing-shaped battery container 9 made of an aluminum alloy material. . Further, a battery case for housing the power generation elements 1 and 1 is formed by fitting the lid plate 4 into the upper end opening of the battery container 9 and sealing the periphery by welding. Then, the battery case is filled with an electrolytic solution, and a liquid inlet (not shown) is sealed to form a non-aqueous electrolyte secondary battery. At this time, the battery case 9 made of an aluminum alloy and the cover plate 4 constituting the battery case have the same potential as the positive electrode terminal 5.
[0022]
According to the above configuration, the positive electrodes 1a, 1a of the two power generating elements 1, 1 are connected and fixed to the connecting plate portion 2b of the current collecting connecting plate 2 by the aluminum foil protruding to one end surface every half turn of the winding. Therefore, the heat generated in these positive electrodes 1a, 1a can be efficiently transmitted from the inner and outer peripheries of the winding to the current collecting and connecting plate 2 made of an aluminum alloy plate. In addition, since the main body 2a is tightly attached to the lower surface of the lid plate 4 made of an aluminum alloy, the current collecting connecting plate 2 on the positive electrode side is caulked to the positive electrode terminal 5 and fixedly connected. The power is efficiently transmitted from the cover plate 4 to the battery case 9 via the power connection plate 2, and the heat can be radiated to the outside through the cover plate 4 and the battery case 9 constituting these battery cases. Therefore, even in the case of the nonaqueous electrolyte secondary battery of the present embodiment in which the lithium-nickel-cobalt-based composite oxide having poor thermal stability is used as the positive electrode active material of the positive electrode 1a, the heat generated in the positive electrode 1a is efficiently used. The battery case can be transmitted to the outside and heat can be radiated to the outside, so by effectively using this battery case as a heat sink, it is possible to prevent thermal runaway during a short circuit or overcharge and prevent abnormal temperature rise of the battery. Will be able to
[0023]
In some conventional large non-aqueous electrolyte secondary batteries, a current collector connecting plate 2 is connected and fixed to the inner and outer peripheries of the positive electrode 1a of the power generating element 1 to collect power. However, if such a large battery has a terminal potential in the battery case, it needs to be handled with care because the stored energy is large. Therefore, similarly to the case of the negative electrode of this embodiment, the current collection of the positive electrode is performed. The connection plate 2 and the positive electrode terminal 5 were insulated from the cover plate 4 so that this battery case did not have a terminal potential. Therefore, in the conventional large non-aqueous electrolyte secondary battery, heat generated in the positive electrode 1a is efficiently conducted only to the positive electrode terminal 5 via the current collecting connection plate 2, and a battery case having a large surface area is used as a heat sink. I couldn't do that. Further, in the conventional small non-aqueous electrolyte secondary battery, an aluminum foil of the positive electrode 1a of the power generating element 1 is brought into contact with the inner surface of the battery case, or a current collecting connection plate 2 to which the aluminum foil is connected and fixed is attached to the battery case. Some were fixedly connected to the inner surface. However, in such a small battery, only the outermost portion of the winding of the positive electrode 1a contacts the inner surface of the battery case or is connected and fixed via the current collecting connection plate 2, so that the The heat generated in the periphery could not be efficiently transmitted to the battery case. On the other hand, in the nonaqueous electrolyte secondary battery of the present embodiment, heat can be efficiently transmitted from the inner and outer peripheries of the positive electrode 1a of the power generating element 1 to the battery case via the current collecting connection plate 2 and the positive electrode terminal 5. Therefore, the battery case can be effectively used as a heat sink. Therefore, this is particularly effective in the case of a large battery that needs to efficiently radiate the heat generated in the inner peripheral portion of the positive electrode 1a. In addition, in the case of such a large battery, since the stored energy becomes large, care must be taken when the battery case has the potential of the positive electrode 1a. This inconvenience in handling can be easily eliminated by covering the battery case or forming a battery pack to surround the periphery with a resin frame.
[0024]
In the above embodiment, the case where the separator 1c is wound around the outermost periphery of each power generating element 1 is shown. However, the positive electrode 1a is wound around the outermost periphery, and these power generating elements 1 are made of an insulating material. It can also be stored directly in the battery container 9 without going through. In this case, since the outermost peripheral surface of the positive electrode 1a is in direct contact with the inner surface of the battery container 9 made of an aluminum alloy, the heat generated in the positive electrode 1a is transmitted through the current collecting connecting plate 2 connected and fixed to the side end. Instead, it can be efficiently transmitted directly to the battery case. At this time, it is preferable that the positive electrode 1a is wound so that the aluminum foil is exposed on the outermost peripheral surface, so that heat is more efficiently transmitted to the battery case 9 without the intervention of the positive electrode active material. Moreover, if the positive electrode active material of the positive electrode 1a of the nonaqueous electrolyte secondary battery does not face the negative electrode active material of the negative electrode 1b, electrodeposition may occur due to repetition of charge and discharge. It is preferable not to apply the positive electrode active material to the outermost peripheral surface of the above. When the positive electrode 1a is wound around the outermost periphery of the power generating element 1, the outer peripheral end of the positive electrode 1a may be connected and fixed to the inner surface of the battery container 9 by welding. Since the internal pressure of the nonaqueous electrolyte secondary battery increases due to the generation of gas or the like during use, the battery container 9 may swell. Therefore, the case where only the outermost positive electrode 1a is in contact with the inner surface of the battery container 9 In this case, there is a possibility that this contact is separated and heat can hardly be transmitted. However, if the battery is connected and fixed to the inner surface of the battery container 9 by welding, the heat of the positive electrode 1a can be reliably transmitted. Will be able to
[0025]
Further, in the above-described embodiment, the case where the main body 2a of the current collecting connection plate 2 is connected and fixed to the positive electrode terminal 5 and the cover plate 4 by caulking is shown, but the connection and fixing may be performed by another method such as welding. Further, the positive electrode terminal 5 and the cover plate 4 do not need to be connected and fixed to the current collecting and connecting plate 2 at the same time, and the positive terminal 5 to which the current collecting and connecting plate 2 is connected and fixed is connected and fixed to the cover plate 4 at another portion. It may be so. Further, since the cover plate 4 and the battery container 9 can be used as the positive electrode terminals as they are, the current collector connection plate 2 can be directly connected and fixed to the cover plate 4 or the battery container 9 without the positive electrode terminal 5. In this case, the positive electrode terminal 5 that does not penetrate inside may be connected and fixed to the upper surface of the lid plate 4. Further, the configuration of the battery case is arbitrary, and is not limited to the configuration in which the upper end opening of the battery container 9 is closed by the cover plate 4. In the above embodiment, the lid plate 4 and the battery case 9 are made of an aluminum alloy in order to increase the thermal conductivity of the battery case used as a heat sink. However, a battery case made of another metal such as stainless steel is used. You can also. Further, in the above-described embodiment, the current collector connecting plate 2 in which four connecting plate portions 2b are protruded in a comb-like shape from the end of the main body 2a is shown. Any structure may be used as long as it connects between the positive electrode 1a or the negative electrode 1b and the terminals 5 and 6.
[0026]
Further, in the above-described embodiment, the case where the battery case and the positive electrode terminal 5 are connected and fixed to the positive electrode 1a of the power generating element 1 via the current collecting connector is shown, but instead of using such a current collecting connector, The positive electrode 1a wound around the outermost periphery of the power generating element 1 may be brought into direct contact with the inner surface of the battery case, and a part or all of the contact portion may be connected and fixed to the inner surface of the battery case by welding. Item 1). In this case, the heat generated in the inner peripheral portion of the power generating element 1 is not efficiently released, but as described above, the heat is efficiently radiated from the outermost periphery of the power generating element 1 and the conventional small non-aqueous electrolyte is used. Unlike the secondary battery, even when the battery case swells with the use of the battery, the connection between the positive electrode 1a and the battery case is maintained, so that the heat can be reliably dissipated.
[0027]
Further, in the above embodiment, the non-aqueous electrolyte secondary battery using the lithium-nickel-cobalt-based composite oxide as the positive electrode active material of the positive electrode 1a was described, but the non-aqueous electrolyte secondary battery using another positive electrode active material was used. The present invention can be similarly applied to a battery. When a lithium-nickel-cobalt-based composite oxide having poor thermal stability is used in order to increase the energy density, it is necessary to surely prevent the thermal escape of the positive electrode 1a, but the thermal stability is higher than this. Even when a lithium-cobalt-based composite oxide or the like is used, if the heat radiation efficiency is poor, the positive electrode 1a may cause thermal runaway. Therefore, according to the present invention, the battery case can be effectively used as a heat sink. Further, since heat can also be generated in the negative electrode 1b, the negative electrode 1b can be replaced with the positive electrode 1a.
[0028]
Further, in the above embodiment, the case where the power generating element 1 wound in a long cylindrical shape is used, but the shape of the winding is arbitrary, and may be a cylindrical shape or the like. Furthermore, although the non-aqueous electrolyte secondary battery in which the two power generation elements 1 and 1 are connected in parallel is shown, the number of the power generation elements 1 is also arbitrary. Further, in the above embodiment, a large non-aqueous electrolyte secondary battery was described, but the present invention is not necessarily limited to a large battery, and the type of battery is not limited to a non-aqueous electrolyte secondary battery. That is, the present invention can be applied to all batteries that require heat radiation from the electrodes of the wound power generating element 1.
[0029]
【The invention's effect】
As is apparent from the above description, according to the nonaqueous electrolyte secondary battery of the present invention, heat is directly transmitted to the battery case from the electrode wound around the outermost periphery of the power generation element, and thus, from this electrode to the outside of the battery case. The heat dissipation efficiency of the battery can be improved, and the abnormal temperature rise of the battery can be prevented. Further, according to the non-aqueous electrolyte secondary battery of the present invention, heat is efficiently transmitted to the battery case from a plurality of locations on the inner and outer peripheries of the power generation element through the current collectors and terminals, so that the electrodes can be transferred to the outside of the battery case The heat dissipation efficiency of the battery can be improved, and the abnormal temperature rise of the battery can be prevented.
[Brief description of the drawings]
FIG. 1, showing one embodiment of the present invention, is an assembled perspective view showing a structure of a nonaqueous electrolyte secondary battery.
FIG. 2, showing an embodiment of the present invention, is an assembled perspective view showing a connection structure between an electrode of a power generation element of a non-aqueous electrolyte secondary battery, a current collecting connection plate, and a terminal.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Power generation element 1a Positive electrode 1b Negative electrode 1c Separator 2 Current collector connection plate 4 Cover plate 5 Positive terminal 6 Negative terminal 9 Battery container

Claims (2)

1. In a non-aqueous electrolyte secondary battery containing a power generation element in which a positive electrode and a negative electrode are wound via a separator in a metal battery case,
   Either the positive or negative electrode wound around the outermost periphery of the power generating element directly contacts the inner surface of the battery case, and a part or all of the contact portion is connected and fixed to the inner surface of the battery case by welding. Non-aqueous electrolyte secondary battery.
2. In a non-aqueous electrolyte secondary battery containing a power generation element in which a positive electrode and a negative electrode are wound via a separator in a metal battery case,
   Either the positive or negative electrode wound on the power generating element is connected and fixed to the current collecting connector at a plurality of locations on the inner and outer circumferences of the winding of the electrode, and the current collecting connector is connected and fixed to the inner surface of the battery case. Or a non-aqueous electrolyte secondary battery fixedly connected to a terminal fixed to the battery case.

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