JPH06290769A - Rolled up type battery - Google Patents

Abstract

PURPOSE:To provide a rolled up type battery having a lead draw out part of facilitating fitting work by providing a low internal resistance value of an electrode. CONSTITUTION:In a rolled up type battery of the first invention, an electrode plate 12 of an electrode 11 has a widening part 121 protruded upward, and the other electrode plate 13 has a widening part 131 protruded downward. The widening parts 121, 131 are connected to pole terminals 21, 22. In the second invention, a conductive mandrel 35 is vertically provided to be fitted to a protrusive part of a pole terminal in a lower surface, and in this mandrel, a core part of an electrode roll is formed to also connect a winding start end part of the one electrode plate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a winding type battery in which thin plate-like electrode plates are spirally laminated and wound with a separator interposed therebetween, and more particularly to a structure for drawing leads from the electrode plates.

[0002]

2. Description of the Related Art In recent years, with the widespread use of portable electronic devices and the like, there is an increasing demand for a battery having a large capacity and a high energy density as a power source thereof. The key to higher energy density of batteries is the shape and structure that can take up a large area of the electrode plate in a limited volume, and the winding type battery is widely used as a typical one.

In a typical roll-up type battery, an electrode roll wound with positive and negative electrode plates is inserted into a draw-formed can that serves as a negative electrode, and an upper lid that serves as a positive electrode terminal and a can that serves as a negative electrode terminal are respectively rolled from the electrode roll. Connect the positive and negative leads of. And
The upper lid is caulked and fixed to the upper part of the can by interposing an insulating material.

The positive and negative leads of the electrode roll are shown in FIG.
As shown in FIG. 5, the lead piece 92 is joined to the end portion 91 of the electrode plate 90. When joining the lead pieces 92 in this manner, a method such as attaching an insulating tape to both sides of the lead pieces 92 is proposed so that the lead pieces 92 will not be electrically short-circuited with an unnecessary portion in the battery. (See Japanese Patent Laid-Open No. 4-329259).

An insulating separator is provided between the positive and negative electrode plates of the electrode roll. In order to ensure the insulation between the electrode plates, the separator provided between the two electrode plates in the vertical direction. Has been proposed (see Japanese Patent Laid-Open No. 3-25865).

Further, a metal hollow cylindrical pin is inserted into the central void portion of the electrode roll to reinforce the electrode roll housed in the battery can, and at the same time, the workability of assembling the electrode roll to the battery can is improved. A method for improving it has also been proposed (see Japanese Patent Laid-Open No. 332481).

[0007]

However, the conventional winding type battery has the following problems. The first problem is that the workability of connecting the lead of the electrode plate to the bottom of the battery can is poor, which requires a lot of man-hours and easily causes quality defects such as short circuit. That is, if the lead (usually the negative electrode) connected to the bottom of the can is short, there is no space in the space, so it is extremely difficult to connect and fix the lead to the bottom of the can. On the other hand, if the lead is made longer, the lead may be bent after the electrode roll is inserted, and the lead may come into contact with a portion other than the bottom of the can to cause a short circuit.

The second problem is that, as shown in FIG. 8, in the structure in which the lead piece is connected to the end 91 of the electrode plate 90, the output voltage is lowered when the electrode plate is elongated or a large amount of current is applied. It means that heat is generated. That is, in the method in which the lead piece is provided only on one end, the distance between the other end 93 and the lead piece 92 is large, so that the internal resistance value of the electrode plate including the lead piece becomes large as a whole, and the heat generation is reduced. (Joule heat) and internal voltage drop occur.

On the other hand, in order to reduce the resistance value of the electrode plate, as shown in FIG. 9, a large number of lead pieces 92 are arranged and bundled to form one lead. It is possible to reduce the internal resistance and suppress heat generation and voltage drop.

However, according to this method, the number of parts increases due to an increase in the number of lead pieces, and the number of steps for attaching the lead pieces to the electrode plate and the number of steps for bundling the lead pieces increase, resulting in an increase in cost as a whole. In view of the above conventional problems, the present invention is to provide a winding type battery having a low internal resistance value of an electrode and a lead lead-out portion which is easy to assemble.

[0011]

According to a first aspect of the present invention, a thin plate-shaped positive and negative electrode plate is wound with a separator interposed therebetween to form an electrode roll, which is formed on an upper surface and a lower surface of a container. A roll-up type battery in which an electrode plate of the electrode roll is connected to an electrode terminal, wherein both electrode plates of the electrode roll have one electrode plate protruding at least in part above the other electrode plate. The electrode plate of the other pole is
At least a part of it is formed with a widened portion protruding downward from the electrode plate of one pole, and the upper widened portion is electrically connected to the upper pole terminal, and the lower widened portion is electrically connected to the lower pole terminal. It is a winding type battery characterized by being connected to.

The most remarkable thing in the present invention is that
That is, the electrode plates have widened portions that project upward or downward, respectively. That is, one electrode plate has a widened portion that projects upward or downward from the other electrode plate at least in part, and the other electrode plate has a widened portion that projects in the opposite direction (downward or upward). Is what you are doing. The widened portions of the electrode plates are connected to the pole terminals on the upper and lower surfaces of the battery, respectively.

On the other hand, according to the second invention of the present application, a thin plate-shaped positive and negative electrode plate is wound with a separator interposed therebetween to form an electrode roll, which is formed on the upper surface and the lower surface of the container. A winding-type battery in which an electrode plate of the electrode roll is connected to a child, the pole terminal formed on the lower surface has an uneven portion for fitting and standing a mandrel, and the uneven portion is provided on the uneven portion. Has an electrically conductive mandrel standing upright, while the electrode roll is wound around the mandrel, and the winding start end of one of the electrode plates is connected to the mandrel. It is in a roll-up battery.

In the second aspect of the invention, what is most noticeable is that the pole terminal on the lower surface has a concavo-convex portion on which a rod-shaped body is fitted and erected. The mandrel is erected, and the starting end of one electrode plate of the electrode roll is connected to the mandrel. The mandrel is a conductive member, and is engaged with the pole terminal on the lower surface so as to be in a conductive state. In the above, the uneven portion may be only the concave portion or the convex portion, or both the concave portion and the convex portion may be formed.

[0015]

[Operation and Effect] The operation and effect of the first invention will be described.
The electrode plates of the electrode roll according to the first aspect of the present invention have widened portions that project upward or downward in opposite directions. Therefore, the widened portion can be used as a lead, and the lead piece (FIG. 8, reference numeral 92) in the conventional device is unnecessary. That is, the widened portion is replaced with the lead piece and connected to the pole terminal, and the lead piece is unnecessary.

Then, the widened portion is formed by punching out an electrode plate,
Since it can be formed at the same time when molding by other means, it is extremely easy to manufacture (see FIG. 2). Also,
The lateral width W (FIGS. 2 and 3) of the widened portion can be freely set large, and by setting the lateral width W large, the internal resistance value of the electrode plate including the leads can be made extremely small. Therefore, output voltage drop and heat generation are suppressed.

Further, since the lateral width W of the widened portion can be increased and the place where the widened portion is formed can be freely selected, the connection work with the pole terminals on the upper and lower surfaces is easy. Also,
Since it is not a thin wire like a lead wire, it is unlikely to bend, and poor contact with parts other than the pole terminals does not easily occur.

Next, the function and effect of the second invention will be described. The starting end portion of one electrode plate of the electrode roll of the present invention is connected to the mandrel, and the mandrel is fitted to the uneven portion of the pole terminal on the lower surface. That is, by connecting the starting end of the electrode plate to the mandrel, it is electrically connected to the pole terminal on the lower surface,
No lead piece is required for the electrode plate.

The mandrel is located at the axial center of the electrode roll, and the starting end of the electrode plate may be connected to the mandrel before starting the winding of the electrode roll. Therefore, the work of connecting the electrode plate and the mandrel is extremely easy. Also, it is extremely easy to set the mandrel upright on the uneven portion of the pole terminal. Therefore, as a whole, the work of connecting the electrode terminals on the lower surface to the electrode roll and the work of assembling the electrode roll into the container are extremely easy.

The electrical connection between the electrode plate and the mandrel is
Since the electrode plates can be widely connected in a plane shape along the axial direction of the mandrel, the resistance value of the electrode plate including the mandrel can be suppressed to be extremely low. Also, the contact resistance can be made extremely small when the mandrel and the pole terminal are fitted by increasing the contact area of the fitting portion.

Therefore, the internal resistance of the electrode plate, including the contact resistance with the pole terminals, can be suppressed to a low level. Therefore,
Heat generation and internal voltage drop due to the resistance of the electrode plate can be suppressed to an extremely low level. Further, the mandrel is erected at the center of the electrode roll and also has a function as a reinforcing material.
As described above, according to the first invention or the second invention of the present application, it is possible to provide a winding-type battery having a low internal resistance value of an electrode and a lead extraction portion which is easy to assemble.

[0022]

【Example】

Example 1 A take-up type lithium battery according to an example of the first invention will be described with reference to FIGS. In this example, a thin plate-shaped positive and negative electrode plate is wound with a separator interposed therebetween to form an electrode roll, and as shown in FIG.
Is a winding type battery 10 in which the electrode plates 12 and 13 of the electrode roll 11 are connected to the pole terminals 21 and 22 formed on the upper surface and the lower surface, respectively.

Both electrode plates 12, 13 of the electrode roll 11
2 and 3, the positive electrode plate 12 forms a widened portion 121 that protrudes above the negative electrode plate 13 in at least a part thereof, while the negative electrode plate 13 forms a positive part in at least a part thereof. A widened portion 131 that protrudes below the electrode plate 12 is formed. And the widened portion 12 above
As shown in FIG. 1, 1 is electrically connected to the positive electrode terminal 21 on the upper surface, and the lower widened portion 131 is electrically connected to the negative electrode terminal 22 on the lower surface.

Each of these will be described in detail below. As shown in FIG. 4, the electrode roll 11 is a thin plate-shaped positive and negative electrode plate 1.
2 and 13 are wound with a separator 14 interposed therebetween. The separator 14 has a lower end 122 of the positive electrode plate 12 and an upper end 132 of the negative electrode plate 13 so as to cover both surfaces of both electrode plates 12 and 13 with one continuous sheet.
It is a folded sheet that is folded back at and.

As shown in FIG. 5, in the separator 14, the outer side surface 1211 of one electrode plate 12 may cover only the end surface 1212 thereof. Then, as shown in FIG. 2, the widened part 121, the upper part of the positive electrode plate 12 and the lower part of the negative electrode plate 13 in which the separator 14 is not folded back,
131 is formed (the widened portion is not shown in FIGS. 4 and 5).

Therefore, when the two electrode plates 12 and 13 are overlapped with each other, as shown in FIG. 3, the widened portions 121 and 131 are exposed from above and below. And separator 1
As shown in FIG. 1, the electrode roll 11 in which both electrode plates 12 and 13 are wound with 4 interposed therebetween has widened portions 121 and 131, which form a part of the electrode plates 12 and 13 on the upper and lower surfaces thereof. Exposed vertically.

As shown in FIG. 1, the electrode roll 11 is housed in a cylindrical container 30 to form a roll-up type battery 10. The roll-up battery 10 includes a cylindrical container 30 that also serves as a negative electrode terminal 22, an electrode roll 11, a positive electrode terminal 21,
It has a positive electrode plate 12 and a reinforcing mandrel 35 at the same potential.

The positive electrode terminal 21 forms the upper lid of the roll-up type battery 10 and is attached to the upper end 321 of the body 32 of the container 30 via an insulating ring 331. The positive electrode terminal 21 is electrically connected to the widened portion 121 of the positive electrode plate 12 via the conductive plate 423, the connecting member 422, and the current collector plate 421.

The upper widened portion 121 and the collector plate 421 are joined by welding or brazing. The upper widened portion 121 does not need to be insulated from the mandrel 35, but is insulated from the body portion 321 of the container 30 via an insulating plate 332.

Exhaust ports 211 and 4231 are provided at the side of the positive electrode terminal 21 and in the center of the conductive plate 423 for discharging gas when the battery is abnormal, and the upper surface of the conductive plate 423 is normally used. A thin plate-shaped safety valve 41 is provided to prevent outside air from entering.

The safety valve 41 breaks when the internal gas pressure generated from the battery exceeds a predetermined value, opens the lower discharge port 4231, and discharges the generated gas from the upper discharge port 211.

On the other hand, the lower widened portion 131 of the electrode roll 11
Are joined to the bottom 31 of the container 30 by welding or brazing. An insulating member 333 is interposed between the bottom portion 31 of the container 30 and the mandrel 35. Further, an insulating sheet 334 for insulating the positive electrode plate 12 and the bottom 31 is provided between the bottom 31 and the lower portion of the electrode roll 11.

Next, the function and effect of this example will be described. In the roll-up type battery 10 of the present example, the electrode plates 12 and 13 of the electrode roll 11 have widened portions 121 and 131, respectively, and the widened portions 121 and 131 are used as the current collector plate 421 or the bottom portion 31 of the container 30. Connected to. Therefore, the electrode plate 1
It is not necessary to provide the lead pieces in 2 and 13 unlike the conventional device, and the number of parts is small.

Since the widened portions 121 and 131 can be manufactured at the same time when the electrode plates 12 and 13 are formed, they can be manufactured at low cost. In addition, the widened portions 121, 1
As shown in FIG. 2, the lateral width W of 31 is sufficiently wide, so that the internal resistance of the electrode plates 12 and 13 and the connection resistance between the electrode plates 12 and 13 and the pole terminals 21 and 22 are also small. ， The overall internal resistance of the battery can be reduced.

Therefore, internal heat generation (Joule heat) and internal voltage drop of the battery are suppressed. In addition, the widened portions 121, 13
1 is not a linear body like a conventional lead, but can be widely formed as shown in FIG. 1, so that the joining work is easy.

The zigzag separator 14 of the electrode roll 11 covers the electrode plates 12 and 13 so as to wrap one end of the electrode plates 12 and 13, as shown in FIGS. There is no contact between the electrode plates 12 and 13 or deterioration of insulation. That is, the electrode plate 1
In the conventional method of interposing a strip-shaped separator having no fold-back between 2 and 13, the separator may be vertically displaced and the electrode plates 12 and 13 may come into contact with each other during winding, or the insulation may deteriorate. Yes, but this is not the case. As described above, according to the present example, it is possible to provide the winding-type battery 10 that has a low internal resistance value of the electrode and has a lead lead-out portion that is easy to assemble.

Embodiment 2 A winding type lithium battery according to an embodiment of the second invention will be described with reference to FIGS. 6 and 7. In this example, a thin plate-shaped positive and negative electrode plate is wound with a separator interposed therebetween to form an electrode roll, and as shown in FIG. It is a winding type battery 10 in which the electrode plates of the electrode roll 15 are connected to the children 23 and 24.

The negative electrode terminal 24 formed on the lower surface is the mandrel 3
6 has a convex portion 33 for fitting and standing up, and a conductive mandrel 36 is erected on the protruding portion 33, while the electrode roll 15 is wound around the mandrel 36. In addition, the winding start end of one electrode plate is connected to the mandrel 36.

Each of these will be described in detail below. As shown in FIG. 7, the electrode roll 15 includes positive and negative electrode plates 16 and 17.
Is wound with the separator 18 interposed.
As shown in the figure, the separator 18 covers the negative electrode plate 17 so as to include it. Then, as shown in FIG. 6, a cylindrical mandrel 36 is arranged at the axis of the electrode roll 15, and the mandrel 36 is erected on the convex portion 33 of the bottom 37 of the container 3 which is the negative electrode terminal 24. There is.

An insulating member 335 is provided between the outer peripheral surface 151 of the electrode roll 15 and the body portion 32 of the container 3. Then, the winding start end portion 171 (FIG. 7) of the negative electrode plate 17 is joined to the mandrel 36, and the negative electrode plate 17 and the negative electrode terminal 2 are connected.
4 and 4 are electrically connected.

Further, the positive electrode plate 16 of the electrode roll 15 has a widened portion (reference numeral 12 in FIG. 2) similar to that described in the first embodiment.
1) The lead portion 161 is provided by a method such as
Connect to the positive electrode terminal 23. The positive electrode terminal 23, which also serves as the lid of the container 3, is provided with a gas outlet 231 and a safety valve 41 for shutting off outside air is provided at the lower part. Then, the positive electrode terminal 23 seals the container 3 via the insulating sealing material 336.

Next, the function and effect of this example will be described. In this example, the winding start end 171 of the negative electrode plate 17 is connected to the mandrel 3
6, the negative electrode plate 17 and the negative electrode terminal 24 are electrically connected by fitting the mandrel 36 to the convex portion 33 of the container 3. Therefore, it is not necessary to provide a connecting member such as a lead piece (FIG. 8) on the negative electrode plate 17.

It is extremely easy to join the winding start end 171 to the mandrel 36 by welding, brazing or the like. Also, the work of standing the mandrel 36 on the bottom of the container 3 is extremely easy. Therefore, the work of connecting the negative electrode plate 17 and the negative electrode terminal 24 and the work of assembling the electrode roll 15 into the container 3 are made much more efficient, and the workability is improved.

Further, since the connection between the negative electrode plate 17 and the negative electrode terminal 24 is not made through a thin lead member as in the conventional case, the internal resistance value of the electrode is greatly reduced. as a result,
Heat generation (Joule heat) due to discharge of the battery and internal voltage drop of the battery are significantly reduced. As described above, according to this example, it is possible to provide a winding type battery having a low lead electrode with a low internal resistance value of the electrode and easy lead-out work.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a roll-up type battery of Example 1.

FIG. 2 is a positive electrode plate (a) and a negative electrode plate (b) of Example 1.
Deployment view of.

FIG. 3 is a development view in which the positive and negative electrode plates of Example 1 are superposed.

FIG. 4 is an explanatory view of winding the electrode roll of Example 1.

FIG. 5 is another winding explanatory view of the electrode roll of Example 1.

FIG. 6 is a cross-sectional view of the roll-up type battery of Example 2.

FIG. 7 is an explanatory view of winding the electrode roll of Example 2.

FIG. 8 is a development view of an electrode plate in a conventional roll-up type battery.

FIG. 9 is a development view of another electrode plate in the conventional roll-up type battery.

[Explanation of symbols]

 10. ． ． Roll-up type battery, 11, 15. ． ． Electrode roll, 12, 13, 16, 17. ． ． Electrode plate, 21-24. ． ． Pole terminal, 3,30. ． ． Container, 35, 36. ． ． Mandrel,

Front page continuation (72) Inventor Tetsuya Nagata 1-1, Showa-cho, Kariya, Aichi Prefecture, Nihon Denso Co., Ltd. (72) Inventor, Masanori Tabayashi, 1-1, Showa-cho, Kariya, Aichi Nidec Corporation

Claims (2)

[Claims] 1. An electrode roll is formed by winding a thin plate-shaped positive and negative electrode plate with a separator interposed therebetween to form electrode rolls, and the electrode of the electrode roll is formed on pole terminals formed on the upper and lower surfaces of the container. A roll-up type battery comprising plates connected to each other, wherein both electrode plates of the electrode roll have a widened portion in which at least a part of the electrode plate of one electrode is projected above the electrode plate of the other electrode. , The electrode plate of the other electrode forms a widened portion protruding below the electrode plate of the one electrode in at least a part thereof,
A roll-up battery, wherein the upper widened portion is electrically connected to a pole terminal on the upper surface, and the lower widened portion is electrically connected to a polar terminal on the lower surface. 2. An electrode roll is formed by winding a thin positive and negative electrode plate with a separator interposed therebetween to form an electrode roll, and the electrode of the electrode roll is formed on an electrode terminal formed on the upper and lower surfaces of the container. In a wound-up battery formed by connecting plates, the pole terminal formed on the lower surface has a concavo-convex portion for fitting and standing the mandrel, and the concavo-convex portion has a conductive mandrel upright. On the other hand, the electrode roll is wound around the mandrel, and the winding start end of one of the electrode plates is connected to the mandrel.