JP3470051B2 - Lithium secondary battery - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention relates to the excellent productivity because the assembling is easy battery structure is a simple Rutotomo
Filling (injecting) and discharging non-aqueous electrolyte easily and quickly
In particular, the present invention relates to a lithium secondary battery having excellent vibration resistance, which is preferably used as a power source for driving a motor of an electric vehicle.

[0002]

2. Description of the Related Art In recent years, lithium secondary batteries have come to be widely used as power source batteries for portable electronic devices such as mobile phones, VTRs, and notebook computers. In addition, since the lithium secondary battery has a large energy density, not only the portable electronic device but also an electric vehicle that is actively spread to the general public as a low-emission vehicle due to recent environmental problems ( It has also attracted attention as a motor drive power source for EVs or hybrid electric vehicles (HEVs).

As a typical EV battery, a current collecting tab (hereinafter referred to as “tab”) 5A as shown in FIG.
The wound type internal electrode body 1 wound around the outer periphery of the winding core 6 is impregnated with the non-aqueous electrolyte through the separator 4 so that the positive electrode plate 2 and the negative electrode plate 3 to which 5B is attached do not contact each other. An example of the battery is a battery having a structure in which the battery is housed in a cylindrical battery case. Here, the length of the winding core 6 is the positive electrode plate 2
It is general that the widths are equal to each other, that is, substantially equal to the length of the internal electrode body 1.

By the way, the EV battery is required to ensure durability against vibration during traveling. For example, when the internal electrode body 1 vibrates or moves inside the battery case,
Not only is the electrode active material applied to the positive electrode plate and the negative electrode plate peeled off, reducing the battery capacity, but also the peeled electrode active material may short-circuit the positive electrode and the negative electrode, which is not preferable. Further, it is not preferable that the end surface of the internal electrode body 1 is initially flat, but is deformed by vibration into a spiral shape or the like to make the battery reaction non-uniform.

Therefore, as a conventional fixing method of the internal electrode body 1, in Japanese Patent Laid-Open No. 9-92241, as shown in FIG. 8, an electrode spiral body 35 (internal electrode body) is used by using a cylindrical winding core 31. 1) was prepared, and the pole 20 whose lower surface was covered with the insulator collar 15 was inserted into the hollow portion of the winding core 31 and the pole 20 was fixed to the cap 13 using the nut 12. A battery 10 having a structure is disclosed. Further, JP-A-1-175176 discloses a battery structure in which a temporary winding core is removed from an internal electrode body produced by using a temporary winding core, and a rod-shaped insulator is inserted instead to be housed in a battery case. Has been done.

[0006]

However, the electrode spiral body 3 disclosed in Japanese Patent Laid-Open No. 9-92241 is disclosed.
In the fixing method of No. 5, the inner peripheral surface of the battery case 17 and the pole 20 only function as a stopper that suppresses the radial movement of the electrode spiral body 35, and the radial movement is not complete. Not only is it not suppressed, but the electrode spiral 35
The structure is such that it can be easily moved in the longitudinal direction by the width of the gap with the pole 20. Here, when the movement of the electrode spiral body 35 in the length direction occurs, the electrode spiral body 35 is moved to the pole column 20.
There is a risk that the electrode lead 11 (corresponding to the tabs 5A and 5B) attached to the end surface of the electrode spiral body 35 may be damaged due to the collision with. In addition, it is considered that the end portion of the electrode spiral body 35 is likely to be damaged such as peeling of the electrode active material.

On the other hand, in the invention described in Japanese Unexamined Patent Publication No. 1-175176, the internal electrode body is of a type that receives pressure from a solid rod inserted between the inner peripheral surface of the battery case and the core of the internal electrode body. However, it is not a structure that suppresses the movement of the internal electrode body in the length direction. As described above, conventionally, the internal electrode body is prioritized to be fixed in the radial direction, and no measures have been taken to positively suppress the movement in the length direction.

By the way, in EV batteries and the like, it is also important to increase the productivity and reduce the manufacturing cost. Here, in the battery 10 having the end structure shown in FIG. 8, the electrolyte injection port 32 and the pressure release valve 1 are provided at both ends of the battery 10.
9, the end structure of the battery 10 is complicated and the number of parts is large, the electrode lead 11 is attached to the outer periphery of the pole 20 by laser welding, and the battery case 17 and the cap 13 are Since the boundary is hermetically sealed by welding, the assembly workability, that is, the productivity is not necessarily good.

Further, in the structure of the battery 10 shown in FIG. 8, the electrolyte solution is filled with the electrolyte solution by degassing from the electrolyte solution inlet 32 at one end, and the inside of the battery is depressurized, and the electrolyte solution inlet at the other end is filled. The means for injecting the electrolytic solution is taken from 32, and this operation is repeated several times. However, performing such an operation several times is disadvantageous in the manufacturing process, and further, providing the electrolytic solution inlet 32 to be finally sealed at both ends causes leakage of the electrolytic solution and deterioration of airtightness. It is disadvantageous in that it is easy to invite.

[0010]

Means for Solving the Problems The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to prevent vibration in the radial direction and the longitudinal direction of the internal electrode body. Of the non-aqueous electrolyte solution (Note)
It is possible to easily and quickly perform insertion and removal , and a simple battery structure that facilitates assembly, reduces manufacturing costs, and provides a highly reliable lithium secondary battery. To provide. That is, according to the present invention,
First, there is a lithium secondary battery in which an internal electrode body formed by winding a positive electrode plate and a negative electrode plate around a winding core via a separator is housed in a cylindrical battery case and a nonaqueous electrolytic solution is used. The core has a hole or a slit at its end.
It has a hollow cylindrical shape and is sandwiched by a lid that seals the end surface of the battery case,
Accommodated and fixed, and the outer extension of the hollow part of the core
Above, the hollow part of the core and the
The non-aqueous electrolyte is poured using the hole or slit as a flow path.
Provided is a lithium secondary battery, which is provided with a non-aqueous electrolyte injection port for inserting and discharging .

In the lithium secondary battery of the present invention, as the winding core, the insulating material or the surface thereof is the insulating material.
A material made of a metal material coated with a material is preferably used .

Further, according to the present invention, secondly, the internal electrode body formed by winding the positive electrode plate and the negative electrode plate around the outer circumference of the winding core with the separator interposed therebetween is housed in the cylindrical battery case, and the non-aqueous electrolysis is carried out. a lithium secondary battery using a liquid, it insulating member extending the length of the core at both ends of the winding core is arranged
The core and the insulating member have a hollow cylindrical shape,
Further, the insulating member has a hole or a slit at its end.
Together comprising Te, is sandwiched by a lid in which the winding core and the insulating member sealing the end face of the battery case, the cell case
It is housed and fixed inside the base, and the core and
And the outside of the hollow part of the insulating member, one of the lids
The core and the hollow part of the insulating member and the insulation.
Using the hole or slit of the edge member as a flow path, the non-aqueous electrolysis
A non-aqueous electrolyte injection port is provided for injecting and discharging the liquid.
Lithium secondary battery characterized by comprising Te, is provided.

[0013]

In the above-mentioned two types of lithium secondary batteries of the present invention, one of the lids is provided with a non-aqueous electrolyte injection port.
This makes it possible to fill the nonaqueous electrolytic solution easily and quickly by utilizing the hollow portion of the winding core and the insulating member. In this case, a hole is provided at the end of the winding core or on the side surface of the insulator so that the electrolytic solution flows out from the hollow portion of the winding core to the outside and the degassing by the injection of the electrolytic solution is facilitated. part or <br/> slits Ru provided Empire.

[0015] Further, in the lithium secondary battery of the present invention, the battery case, between the end face and the lid of the internal electrode body, be provided with a projection which projects to the inner peripheral side of the battery case Is preferred, and such protrusions are
It can be easily formed by subjecting the battery case to drawing. Then, it is preferable to fix the lid to the battery case by caulking it by using the above-mentioned protrusion, because the battery can be easily assembled.

Furthermore, an internal terminal having a collective connecting portion for collectively connecting the current collecting tabs attached to the positive electrode plate and the negative electrode plate at one location, and the collective connecting portion is provided from the outer periphery of the winding core to the internal electrode body. The battery structure can be made simple by facilitating the battery assembling work by arranging the region extending to the outer periphery of the battery in a range extending in the axial direction of the winding core and attaching it to at least one lid. It is preferable because it contributes to the improvement of the characteristics.

The lithium secondary battery of the present invention is suitable for use as a power source for driving a motor of an electric vehicle or a hybrid electric vehicle, taking advantage of its excellent vibration resistance, and has a battery capacity of 2 Ah or more. It is preferably applied in the case of.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. First, FIG. 1 shows an internal electrode body 4 preferably used in the lithium secondary battery of the present invention.
It is a perspective view which shows the structure of 0. Compared with the internal electrode body 1 shown in FIG. 5, the winding core 41 is axially long and has a shape protruding from the end faces of the positive electrode plate 2 and the negative electrode plate 3.
The internal electrode body 40 is wound around the outer periphery of the winding core 41 via the separator 4 so that the positive electrode plate 2 and the negative electrode plate 3 do not come into contact with each other, and a positive electrode tab for collecting current during the winding operation. 5A and the negative electrode tab 5B are attached to the positive electrode plate 2 and the negative electrode plate 3, respectively, by means of ultrasonic welding or the like.

Here, the positive electrode tab 5 A and the negative electrode tab 5
It is preferable that Bs are attached at substantially equal intervals so that the current collecting areas covered by one tab are substantially equal, and further, after winding, they are attached so as to be arranged substantially linearly in the radial direction on the end surface of the internal electrode body 40. This is preferable because it facilitates collective connection of tabs. Aluminum foil is preferably used for the positive electrode tab 5A, and copper foil is preferably used for the negative electrode tab 5B.

The positive electrode plate 2 is usually produced by applying a positive electrode active material to a predetermined thickness on both sides of an aluminum foil or a titanium foil as a current collector, and it is cost-effective to use an inexpensive aluminum foil. preferable. The positive electrode active material is applied by applying and fixing a slurry or paste prepared by adding a solvent, a binder, etc. to the positive electrode active material powder by using a roll coater method or the like. Examples of the positive electrode active material that is preferably used include lithium transition metal composite oxides such as lithium manganate, lithium cobalt oxide, and lithium nickel oxide. It is preferable to add fine carbon powder such as acetylene black to the positive electrode active material as a conductive additive.

On the other hand, the negative electrode plate 3 is manufactured by applying a negative electrode active material to both surfaces of a copper foil or a nickel foil as a current collector. The manufacturing method is similar to that of the positive electrode plate 2 described above. As the negative electrode active material, an amorphous carbonaceous material such as soft carbon or hard carbon, or highly graphitized carbonaceous powder such as artificial graphite or natural graphite is used.

Further, the separator 4 has a three-layer structure in which a lithium ion permeable polyethylene film (PE film) having micropores is sandwiched between porous lithium ion permeable polypropylene films (PP film). It is preferably used. This is because when the temperature of the internal electrode body 40 rises, the PE film is about 1
It also functions as a safety mechanism that suppresses the movement of lithium ions, that is, the battery reaction, by softening at 30 ° C. to crush the micropores. By sandwiching this PE film between PP films having a higher softening temperature, even when the PE film is softened, the PP film retains its shape and prevents contact and short circuit between the positive electrode plate 2 and the negative electrode plate 3. Therefore, it is possible to surely suppress the battery reaction and ensure safety.

It is preferable that the outer periphery of the internal electrode body 40 be covered with the separator 4 because the internal electrode body 40 can be easily insulated from the battery case when the internal electrode body 40 is inserted into the battery case. Further, it is preferable to fix the outer periphery of the internal electrode body 40 with an insulating tape or the like so that the internal electrode body 40 cannot be loosened.

Now, FIG. 2 is a sectional view showing an embodiment of the structure of the lithium secondary battery according to the present invention using the above-mentioned internal electrode body 40. Hereinafter, the lithium secondary battery 50
The structure of (hereinafter, referred to as "battery 50") will be described in accordance with its manufacturing procedure. In producing the battery 50, first, the positive electrode tab 5A and the negative electrode tab 5B attached to both ends of the internal electrode body 40 are connected to the internal terminals 74A and 74B, respectively. Here, the internal terminals refer to members that collectively and collectively connect the tabs inside the battery,
An internal terminal 74A for connecting the positive electrode tab 5A is preferably made of aluminum or an aluminum alloy, and an internal terminal 74B for connecting the negative electrode tab 5B is preferably made of copper or a copper alloy.

In addition, the internal terminals 74A.7 in FIG.
As the 4B, a rivet-like one is illustrated in which the tabs 5A and 5B are connected by crimping, but the shape is not limited. Further, since aluminum and copper easily form an oxide film on the surface thereof, the oxide film forms a tab 5A.
The contact resistance between 5B and the internal terminals 74A and 74B may increase and the value may vary. Therefore, in order to suppress the variation of the contact resistance at the connection portion, the collective connection of the tabs 5A and 5B to the internal terminals 74A and 74B is preferably performed by welding, caulking, or eyelets. In the case of caulking or eyelets, It is preferable to apply a pressure that is large enough to break the oxide film described above and that is kept within a range that does not damage or damage the tabs 5A and 5B. Regarding the method of connecting the tabs 5A and 5B collectively, the present inventors have
The contents thereof have already been disclosed in Japanese Patent Application No. 10-171105.

The internal terminals 74A and 74B are pre-mounted on the lids 71A and 71B, respectively, and at the same time, the lids 71A and 74B are simultaneously attached.
It is preferable that the external terminals 73A and 73B are attached to the other surfaces of the 71B on which the internal terminals 74A and 74B are arranged. Even in such a state, the tabs 5A and 5B can be connected together. No hindrance will occur. Here, the lid is a member for sealing the end portion of the battery, and as the material thereof, the same metal material as the internal terminal such as aluminum or copper is preferably used. The external terminal is a terminal member for taking out an electric current to the outside of the battery, and the material thereof is not particularly limited as long as it is a solid metal material.

It should be noted that the inner terminals 74 A and 74 B are capped so that their collective connecting portions are located in a range extending in the axial direction of the winding core 41 from the outer circumference of the winding core 41 to the outer circumference of the internal electrode body 40. When attached to 71A / 71B, tab 5
Compared with the case where A.5B is attached to the outer peripheral portions of the lids 71A and 71B, etc., the overall length of the tabs 5A and 5B can be shortened to reduce the resistance and the battery characteristics can be improved, which is preferable. In addition, as the external terminals 73A and 73B, a male screw is illustrated on one side and a female screw is illustrated on the other side. With such a structure, the series connection of the plurality of batteries 50 can be easily performed and the contact resistance can be improved. It becomes possible to perform firmly so that it becomes small.

In order to utilize such characteristics, the internal terminals 74A and 74B, the lids 71A and 71B, and the lids 71A and 7
It is preferable that 1B and the external terminals 73A and 73B are strongly joined together by welding so that the contact resistance becomes small. Of course, those integrally molded are also preferably used. In this way the lid 71A ・ 71
When B is made of a metal material, the internal terminals 74A, 74
B and the external terminals 73A and 73B are inevitably conducted to form a current path. In this case, the structure of the battery end portion is simplified, and the workability of assembling the battery is improved.

On the other hand, it is possible to use an insulating material such as hard resin or ceramic for the lids 71A and 71B. However, in this case, it is necessary to use the outer circumference of the lids 71A and 71B or to form a current path so as to penetrate the lids 71A and 71B, which complicates the shape of parts and lowers the airtightness of the battery. There is a problem such as the possibility of causing

In this way, the internal electrode body 40 to which the lids 71 A and 71 B and the like are attached is inserted into the cylindrical battery case 72. As the battery case 72, a metal pipe is preferably used, and an aluminum pipe or a stainless pipe is preferably used. In this way, the battery case 72
Since a metal member is used as the battery case 72
It is preferable to sandwich an insulating film 79 between the inner surface of the inner electrode body 40 and the outer periphery of the inner electrode body 40 to prevent conduction between the inner electrode body 40 and the battery case 72 and conduction between the tabs 5A and 5B and the battery case 72. However, as described above, when the entire outer periphery of the internal electrode body 40 is covered with the separator 4, the insulating film 79 is not necessarily required in the outer peripheral portion of the internal electrode body 40.

Regardless of the mode of use of the insulating film 79, in order to suppress the radial movement of the internal electrode body 40, the outer periphery of the internal electrode body 40 and the battery can be inserted to the extent that it is not difficult to insert the internal electrode body 40. The clearance with the inner surface of the case 72 is preferably small, and more preferably, the internal electrode body 40 is preferably designed so as to receive a compressive stress from the battery case 72 after the battery is completed.

Thus, in a state where the internal electrode body 40 is inserted into the battery case 72, the tabs 5A and 5B are provided near the end surface of the internal electrode body 40 and between the lids 71A and 71B.
In consideration of the length of the winding core 41, the battery case 72 is subjected to a drawing process to form the protrusion 81 protruding toward the inner peripheral side. The formation of the projecting portion 81 facilitates fixing of the lids 71A and 71B and also plays a supplementary role of suppressing the movement of the internal electrode body 40 in the longitudinal direction. Further, the formation position of the projection 81 plays an important role in determining the fixing position of the lids 71A and 71B.

Using the formed projection 81, the sealing material 82 is sandwiched between the lids 71 A and 71 B and the battery case 72, and the end of the battery case 72 is caulked. In this way, both ends of the battery case 72 are sealed, and the core 41 is sandwiched by the lids 71A and 71B,
It is housed and fixed inside the battery case 72 . At this time,
The winding core 41 may be fixed only depending on the pressure received from the lids 71A and 71B, but the lids 71A and 71B are formed with grooves or protrusions complementary to the end shape of the winding core 41, Using these, the lid 71 is accurately positioned.
It is preferable that the A-71B is sandwiched and fixed.

In this way, the internal electrode body 40 has the winding core 41.
Therefore, the movement in the axial direction is suppressed. Furthermore, as described above, the protrusion 81 also suppresses the movement of the internal electrode body 40 in the lengthwise direction. Thus, since the movement of the internal electrode body 40 in the length direction and the radial direction is suppressed, the vibration resistance is remarkably improved as compared with the conventional lithium secondary battery.

As the sealing material 82, a polymer material excellent in corrosion resistance to an electrolytic solution and having a good sealing property for preventing leakage of the electrolytic solution during caulking, such as polyethylene, polypropylene, ethylene propylene elastomer, Styrenic elastomers, olefinic elastomers, ethylene propylene rubber, butyl rubber, styrene butadiene rubber, and fluororubber are preferably used.

In this way, the internal electrode body 40 is firmly fixed, and the internal electrode body 40 itself is prevented from vibrating or moving due to vibration or the like, so that the electrode active material is peeled off or the internal electrode body 40 itself is deformed. In addition to being suppressed, the stress that has been conventionally applied to the tabs 5A and 5B due to the vibration of the internal electrode body 40 and the like is also reduced, and the battery life is extended.

Now, as described above, the lids 71A and 71B
A metal material is preferably used as the
Since it is in contact with 1A and 71B, an insulating material as the winding core 41 , or a metal material whose surface is covered with an insulating material
Those composed of charge is suitably used. Specifically, examples of the insulating material include resins such as polypropylene and bakelite, and ceramics such as alumina. Further, examples of the metal material include aluminum, copper, stainless steel, and the like, and examples of the method of insulating coating thereof include a method of fixing a fluororesin or the like and forming a film with a heat-shrinkable film. Strictly speaking, at least the end surface of the winding core 41 may be made of an insulating material. Naturally, the positive electrode plate 2 and the negative electrode plate 3 are wound around the outer circumference of the winding core 41 so as to be insulated from the winding core 41. To be turned.

Next, a method of filling the non-aqueous electrolyte solution (hereinafter referred to as “electrolyte solution”) in the battery 50 will be described. One method is to place only one of the battery cases 72 in a sealed state, place the other opening in the decompressed atmosphere with the other opening facing upward, and inject the electrolytic solution into the internal electrode body 40.
After the internal electrode body 40 is sufficiently impregnated with a predetermined amount of electrolytic solution, the unnecessary electrolytic solution is discharged under an inert gas atmosphere,
Finally, it is a method of sealing the opening.

However, in this method, it takes time to impregnate the internal electrode body 40 with the electrolytic solution, and it is necessary to take care to keep the inside of the battery in an inert gas atmosphere until the opening is sealed. There is a problem in workability.
Here, it is possible to shorten the impregnation time by impregnating the electrolyte solution from the sealed battery end (lower part) using the hollow part of the winding core 41, but to maintain the atmosphere inside the battery The problem of remains the same.

[0040] Therefore, using the one having a hollow cylindrical shape as a winding core 41, when <br/> sealing the both ends of the battery case 72, on the extension of the hollow portion of the core 41, the lid 71A ·
(In FIG. 2, the lid 71A) either one of 71B due to the electrolyte injection hole 77 is configured to be positioned
Te, it is possible to perform the filling of the hollow portion electrolyte using a winding core 41 after sealing of the battery case 72 easily and quickly
It Further, the electrolyte solution inlet that leads to leakage of the electrolyte solution and deterioration of airtightness can be stopped at only one location, and reliability can be improved.

In this case, it is necessary to allow the electrolytic solution to flow out from the hollow portion of the winding core 41 to the outside of the winding core 41 and to facilitate degassing by injecting the electrolytic solution. Figure 3
FIG. 3 is a perspective view showing a preferred embodiment of the winding core 41,
Provided holes 42 or slits 43 and the like on the end portion of the core 41
There is .

In this way, the battery case 72 having the core 41 housed therein and having both ends sealed is placed in a reduced pressure atmosphere,
Through the electrolyte injection port 77, insert the tip of the electrolyte injection nozzle into the vicinity of the opposite end face (lower part of the battery 50),
Sufficient impregnation is performed by injecting a predetermined amount of electrolytic solution. Then, after the atmosphere is made inert, the unnecessary electrolyte remaining in the lower portion of the battery 50 or the hollow portion of the winding core 41 is discharged by using the electrolyte injection nozzle as a discharge nozzle. Finally, the assembly of the battery 50 is completed by sealing the electrolyte injection port with a screw or the like in an inert atmosphere.

As the electrolytic solution, a carbonate-based one such as ethylene carbonate (EC), diethyl carbonate (DEC) and dimethyl carbonate (DMC), an organic solvent such as propylene carbonate (PC), γ-butyrolactone, tetrahydrofuran and acetonitrile. Li as an electrolyte in a single solvent or a mixed solvent of solvents
A lithium complex fluorine compound such as PF ₆ or LiBF ₄ , or a lithium halide such as LiClO ₄ is used.
A non-aqueous electrolyte solution in which one kind or two or more kinds are dissolved is preferably used. Further, the injection amount of the electrolytic solution may be experimentally obtained in advance while observing the water level using a battery whose one end is sealed. Further, if the impregnation process is performed while measuring the resistance between the external terminals 73A and 73B, it is possible to determine the end of the impregnation process when the resistance value decreases to a predetermined value.

Generally, in a lithium secondary battery, when the battery temperature rises due to overcharging or overdischarging, the electrolyte solution evaporates and the internal pressure of the battery rises to prevent the battery from bursting. As a safety mechanism, the pressure relief valve is provided at the end of the battery, but it goes without saying that the structure of the battery 50 described above has no adverse effect on the disposition of the pressure relief valve. For example, FIG. 4 is a plan view of the end surface of the battery 50, that is, the lid 71 </ b> A as viewed in the length direction of the battery 50.
A hole 85 is provided in a part of A, and the metal foil 86 is attached by welding or the like so as to close the hole.
6 functions as a pressure release valve that releases the battery internal pressure to the atmospheric pressure by rupturing only the metal foil 86 when the battery internal pressure rises.

Next, FIG. 6 shows a sectional view showing another embodiment of the lithium secondary battery according to the present invention. In the battery 60 shown in FIG. 6, as the internal electrode body, the conventional internal electrode body 1 shown in FIG. 5, that is, the length of the winding core 6 is the positive electrode plate 2.
And the like, and the winding core 6 does not project extremely, and the insulating members 7 that extend the length of the winding core 6 are arranged at both ends of the winding core 6. Then, the winding core 6 and the insulating member 7 seal lids 71A and 71B for sealing the end surface of the battery case 72.
It is sandwiched by and is fixed inside the battery case 72 .

Here, as a method of arranging the insulating members 7 on both ends of the winding core 6, as shown in FIG. 6, a portion having a different outer diameter is provided by changing the thickness of the insulating member 7, A method of inserting a portion having a short diameter into the hollow portion of the winding core 6 or an insulating member having an uneven portion 8 provided at an end portion of the winding core 6 as shown in FIG. A method of using the member 7 may be used.

As the core 6, various materials such as metal, resin, and ceramic can be used as long as they have mechanical strength for maintaining the battery structure and electrolytic solution corrosion resistance. Is. Further, as the insulating member 7, it is preferable to use an insulating resin such as polypropylene or bakelite or a ceramic such as alumina.

Thus, by using the internal electrode body 1 in which the winding core 6 is extended by the insulating member 7, the battery 60 can be manufactured by the same manufacturing method as that of the battery 50 described above. Here, in a hollow cylindrical shape as the winding core 6 and the insulating member 7 is shown in FIG. 6, one of the lid, for example, electrolyte extensional on position of the hollow portion of the core 6 and the insulating member 7 in the lid 71A By providing the injection port 77, it is possible to use the above-described method of filling the battery 50 with the electrolytic solution after the battery is sealed. In this case, the hole 42 shown in FIG.
Alternatively, a hole or slit similar to the slit 43 may be formed in the insulating member 7 as shown in FIG.
It is provided on the end side that contacts 1B.

Although the embodiment of the lithium secondary battery of the present invention has been described above, it goes without saying that the present invention is not limited to the above embodiment. The lithium secondary battery of the present invention is easy to manufacture due to the simple battery structure, and further, it is possible to reduce the weight because the number of parts is small. Therefore, the lithium secondary battery of the present invention is suitable for use as a power source for driving a motor such as EV or HEV, taking advantage of the excellent vibration resistance and lightness of the lithium secondary battery of the present invention. it can. The battery capacity is preferably 2 Ah or more in consideration of such applications, the battery assembling method described above, the battery structure, and the like.

[0050]

As described above, in the lithium secondary battery of the present invention, the internal electrode body is fixed by the winding core in the lengthwise direction and is fixed by the battery case in the radial direction. difficult to occur the movement and deformation of the internal electrode body, the excellent vibration resistance is obtained together
At the time of filling (injecting) and discharging the hollow core core,
By positively using it as the electrolyte flow path in
Filling (injecting) and discharging non-aqueous electrolyte easily and quickly
It becomes possible. Further, since the battery structure is simple, it is easy to assemble and the weight is reduced. As a result, the lithium secondary battery of the present invention has remarkable effects of improving reliability and durability and improving productivity. This effect can be particularly remarkably obtained when used in a vibrating environment such as a motor driving power source such as an EV.

[Brief description of drawings]

FIG. 1 is a perspective view showing the structure of a wound internal electrode body preferably used in the present invention.

FIG. 2 is a cross-sectional view showing an embodiment of a battery structure that is preferably adopted in the lithium secondary battery of the present invention.

FIG. 3 is a perspective view showing one form of a winding core that is preferably used for the internal electrode body of the lithium secondary battery of the present invention.

FIG. 4 is a plan view showing one form of a pressure release valve that is preferably arranged on the end surface of the lithium secondary battery of the present invention.

FIG. 5 is a perspective view showing a general structure of a conventional wound type internal electrode body.

FIG. 6 is a cross-sectional view showing another embodiment of a battery structure suitably adopted for the lithium secondary battery of the present invention.

FIG. 7 is a perspective view showing an embodiment of a winding core extension method in the lithium secondary battery of the present invention.

FIG. 8 is a cross-sectional view showing an example of an end structure of a conventional lithium secondary battery.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Internal electrode body, 2 ... Positive electrode plate, 3 ... Negative electrode plate, 4 ... Separator, 5A / 5B ... Tab, 6 ... Core, 7 ... Insulating member, 8
... concavo-convex portion, 10 ... battery, 11 ... electrode lead, 12 ... nut, 13 ... cap, 15 ... insulator collar, 17 ... battery case, 19 ... pressure relief valve, 20 ... pole column, 31 ... core, 32
... Electrolyte injection port, 35 ... Electrode spiral body, 40 ... Internal electrode body, 41 ... Core, 42 ... Hole portion, 43 ... Slit, 50 ...
Lithium secondary battery (battery), 60 ... Battery, 71A / 71
B ... Lid, 72 ... Battery case, 73A / 73B ... External terminal, 74A / 74B ... Internal terminal, 77 ... Electrolyte injection port,
79 ... Insulating film, 81 ... Protrusion, 82 ... Sealing material,
85 ... Hole, 86 ... Metal foil.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-6-333599 (JP, A) JP-A-8-250084 (JP, A) JP-A-10-125347 (JP, A) JP-A-10- 144339 (JP, A) JP, 7-14609 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01M 10/36-10/40 H01M 10/04 H01M 2/04

Claims (8)

(57) [Claims] 1. A lithium secondary battery in which a non-aqueous electrolyte is used in which an internal electrode body formed by winding a positive electrode plate and a negative electrode plate around a winding core with a separator interposed therebetween is housed in a cylindrical battery case. And the core is hollow with a hole or slit at its end.
It has a cylindrical shape and seals the end surface of the battery case.
It is clamped by the lid that holds it and is stored inside the battery case.
Volume, fixed, and on the outer extension of the hollow part of the winding core, on one of the lids,
The hollow part of the core and the hole or slit are used as the flow path.
Non-aqueous electrolyte for injecting and discharging the non-aqueous electrolyte
A lithium secondary battery, which is provided with an inlet . 2. The winding core comprises an insulating material or a surface thereof.
The lithium secondary battery according to claim 1, wherein the lithium secondary battery is made of a metal material coated with the insulating material . 3. A lithium secondary battery comprising a non-aqueous electrolytic solution in which an internal electrode body formed by winding a positive electrode plate and a negative electrode plate around a winding core via a separator is housed in a cylindrical battery case. there are, insulating member extending the length of the core at both ends of the winding core will be is arranged, the winding core and the insulating member has a hollow cylindrical shape,
The insulating member shall have holes or slits at its end.
In addition, the winding core and the insulating member are
The battery case is sandwiched by the lid that seals the end surface of the battery
Is housed and fixed inside, and on the outer extension of the hollow portion of the winding core and the insulating member,
On one side of the lid, the hollow core of the winding core and the insulating member is aligned.
And the hole or slit of the insulating member as a flow path.
Non-aqueous electrolyte injection port for injecting and discharging the non-aqueous electrolyte
A lithium secondary battery characterized by being provided with . 4. The battery case projects between the end surface of the internal electrode body and the lid toward the inner peripheral side of the battery case.
Claim 1-3, characterized in that it comprises an the protrusion
The lithium secondary battery according to any one of 1. 5. The battery case , wherein the lid is caulked.
The lithium secondary battery according to any one of claims 1 to 4, is fixed, characterized in Rukoto such in the. 6. An internal terminal having a collective connecting part for collectively collecting and connecting the current collecting tabs attached to the positive electrode plate and the negative electrode plate at one location, wherein the collective connecting part is provided from the outer periphery of the core. the region extending to the outer periphery of the internal electrode body so as to be positioned in the range that is extension in the axial direction of the winding core, claim 1-5, characterized in that attached to at least one said lid The lithium secondary battery according to item 1. 7. A lithium secondary battery according to any one of claims 1 to 6, characterized in that used as a power source for driving a motor of an electric vehicle or hybrid electric vehicle. 8. A lithium secondary battery according to any one of claims 1 to 7, characterized in that it has a battery capacity of more than 2Ah.