JP2011008944A - Battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery in which insulation between a power generation element and a case can be performed, without fail.SOLUTION: In the battery having a winding type power generating element 3 housed in the case 2, a winding shaft member 4A inserted into a winding shaft space 3K formed in a winding center part of the power generating element 3 is provided at an insulating member 4B disposed on at least one end side of the power generation element 3, and the insulating member 4B is made of a U-shaped member, fixed by being pinched from both sides in the width direction of the power generating element 3.

Description

  The present invention relates to a battery including a case with a wound-type power generation element in which strip-shaped positive and negative electrodes are wound via a strip-shaped separator.

  Conventionally, this type of battery has two terminals that are configured so that a wound-type power generation element can be accommodated in a case and are electrically connected to a positive electrode and a negative electrode of the power generation element accommodated through a lead body. Has been proposed that includes a pair of structures for insulating the power generating element and the case by covering the power generating element with the lead body and covering both ends in the winding axis direction with the lead body. (For example, refer to Patent Document 1).

  Also, a configuration has been proposed in which an insulating tape is attached to the surfaces of both ends of the power generation element in the winding axis direction so as to follow the winding direction of the power generation element to insulate the power generation element from the case. (For example, refer to Patent Document 2).

JP 2006-40901 A JP 2006-196276 A

  According to the configuration of Patent Document 1, since the power generation element is a configuration in which a thin and soft belt-like material such as an aluminum foil or a copper foil is wound, the shape retaining strength at both ends in the winding axis direction of the power generation element is particularly low. For this reason, although the structure covers both ends of the power generation element in the winding axis while enclosing the lead body, the structure is detached from the power generation element due to vibration or the like and is displaced upward due to friction with the case. In some cases, sufficient insulation could not be performed.

  Further, according to the configuration of Patent Document 2, when the power generation element is inserted into the case, the tape attached to the surfaces of the power generation element at both ends in the winding axis direction may be caught on the end of the case and torn. There was room for improvement.

  Accordingly, the present invention has been made in view of such a situation, and an object of the invention is to provide a battery capable of reliably performing insulation between the power generation element and the case.

  That is, the battery of the present invention is inserted into a winding space formed in the winding center portion of the power generation element in the battery in which the winding type power generation element is accommodated in the case in order to solve the above-described problem. The winding shaft member is provided in an insulating member disposed on at least one end side in the winding shaft direction of the power generation element.

  According to the above configuration, by inserting the winding member into the winding space, the movement of the winding member in the winding space is prevented, and as a result, the insulating member is displaced or detached from one end of the power generation element. Can be reliably prevented. In addition, the winding shaft member may be integrally formed with the insulating member, or the winding shaft member and the insulating member may be separately manufactured and integrated.

  In the battery of the present invention, the insulating member may be a U-shaped member that sandwiches the outer surface of the power generating element.

  By setting it as the said structure, there exists an effect which an insulating member becomes much more difficult to shift | deviate or remove | deviate with respect to a power generation element.

  By the way, when the battery is continuously used at a high temperature, the active material repeatedly expands and contracts with charge / discharge, and the positive electrode and the negative electrode may be bent. And although there exists a possibility that the discharge capacity of a battery may fall because of the bending, it can only aim at the intensity | strength improvement of electric power generation element itself by inserting a winding shaft member in a winding shaft space as mentioned above. In addition, since the power generation element is fixed between the portion of the U-shaped insulating member covering the outer surface of the power generation element and the winding shaft member, the positive electrode and the negative electrode are not easily bent as described above, and the discharge capacity Can be suppressed.

  In the battery according to the present invention, by inserting the winding shaft member into the winding space, it is possible to reliably prevent the insulating member from being displaced or detached from one end of the power generation element. It is possible to provide a battery that can reliably insulate the battery.

  In addition, since the winding member is inserted into the winding space, not only can the strength of the power generation element itself be increased, but also the portion of the U-shaped insulating member that covers the outer surface of the power generation element and the winding shaft Since the power generation element is fixed between the members, it is difficult for the positive electrode and the negative electrode to bend as described above, and it is possible to suppress a decrease in the discharge capacity of the battery.

It is a vertical front view of the battery which concerns on this invention. It is a perspective view which shows the state just before inserting a clip in an electric power generation element. It is a perspective view which shows the state pinched | interposed into the electric power generation element with the clip. It is a side view which shows the state just before mounting | wearing a collector with the electric power generation element pinched | interposed with the clip. It is a side view which shows the state just before mounting | wearing the electric power generation element which mounted | wore the collector with the insulating member provided with the winding shaft member. It is a front view which shows the state just before mounting | wearing the electric power generation element which mounted | wore the collector with the insulating member provided with the winding shaft member. It is a top view which shows the state which mounted | wore the electric power generation element with which the electrical power collector was mounted | worn with the insulating member provided with the winding shaft member. (A), (b), (c) shows the 2nd insulation member provided with the winding shaft member, (a) is the side view, (b) is the top view, (c) is the longitudinal front view (D) is a top view of the 3rd insulation member provided with the winding shaft member.

  Hereinafter, an embodiment of a battery according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a longitudinal front view of a nonaqueous electrolyte battery (hereinafter simply referred to as a battery) 1 in the present embodiment. The battery 1 is disposed between two power generation elements 3 and 3 in a long cylindrical shape housed horizontally in a case 2 with the winding axis direction being horizontal, and between each power generation element 3 and the case 2. Insulating members 4B and 5B having winding shaft members 4A and 5A are provided. Here, the battery 1 including two power generation elements 3 and 3 is shown, but a battery including one power generation element may be used, or a battery including three or more power generation elements. May be.

  The case 2 is configured as an upper open type with the upper end opened, and the upper end opening of the case 2 is closed by a rectangular lid body 6. A positive electrode terminal 7 and a negative electrode terminal 8 are provided on both sides in the longitudinal direction of the lid body 6 so as to protrude upward.

  The power generation element 3 is obtained by winding a positive electrode and a negative electrode in a long cylindrical shape via a separator. The positive electrode has a positive electrode active material supported on the surface of a strip-shaped aluminum foil, and the negative electrode has a negative electrode active material supported on the surface of a strip-shaped copper foil. Each of the positive electrode and the negative electrode is provided with an uncoated portion where no active material is applied at one side end of the belt-like shape, and the aluminum foil and the copper foil are exposed at the uncoated portion.

  A current collector 9 is connected to each of both ends in the winding axis direction of each power generation element 3, one of the current collectors 9 is connected to the positive electrode terminal 7, and the other is connected to the negative electrode terminal 8.

  In order to connect the current collector 9 to the power generation element 3, first, as shown in FIG. 2, two clips 10, 10 are first attached to one end in the winding axis direction of the power generation element 3. 10B is inserted until it contacts the end of the power generation element 3. Each clip 10 is made of a single rectangular metal plate. That is, a pair of bent portions are formed by making cuts from one end in the short side direction at positions of a set distance from both ends in the long side direction of the plate, and bending the portions from these cuts to both ends in the long side direction of the plate, respectively. The clip 10 provided with 10A and 10B is comprised. Next, as shown in FIG. 3, the pair of bent portions 10 </ b> A and 10 </ b> B of each inserted clip 10 is bent to the outside of the power generation element 3 by 90 °, thereby sandwiching the power generation element 3 with the clip 10.

  In a state where the power generation element 3 is sandwiched between the clips 10 and 10, the current collector 9 is connected to the power generation element 3 via the clips 10 and 10 as shown in FIG. 4. The current collector 9 includes four vertical connection portions 9A, 9A, 9A, and 9A that are welded in contact with the two sets of clips 10, 10, 10, and 10, and the four connection portions 9A and 9A. , 9A, 9A, a main body portion 9B that extends in the horizontal direction from the upper ends of the power generation elements 3 and is located above the power generation element 3 and connected to the positive terminal 7 and the negative terminal 8, respectively.

  As shown in FIG. 5, by moving the current collector 9 from the upper side to the lower side with respect to the two sets of clips 10, the connecting portions 9 </ b> A are brought into contact with the pair of bent portions 10 </ b> A and 10 </ b> B. Then, the central plate portion 10C of the clip 10 is bent outward to sandwich the connecting portion 9A. In this sandwiched state, the connecting portion 9A, the clip 10, and the power generation element 3 are joined by performing ultrasonic welding on the plate portion 10C.

  Subsequently, the two insulating members 4B and 5B provided with the winding shaft members 4A and 5A are inserted toward the power generation element 3 as shown in FIG. Each of the insulating members 4B and 5B is made of a synthetic resin, and is formed of a U-shaped member that is sandwiched and fixed from both sides in the width direction of the power generation element 3. That is, it consists of a pair of plate portions that are parallel to each other and a connecting plate portion that connects these plate portions at the same end. And plate-shaped winding member 4A and 5A inserted in the winding space 3K formed in the winding center part of the electric power generation element 3 in the width direction approximate center part of the connection board part of each insulation member 4B and 5B. It has. The winding shaft members 4A and 5A are made of synthetic resin and are integrally formed with the insulating members 4B and 5B. The winding shaft members 4A and 5A have an arc shape in which the insertion-side tips 4T and 5T are rounded, and the winding shaft members 4A and 5A can be smoothly inserted into the winding shaft space 3K. Yes. In addition, the thickness of winding shaft member 4A and 5A can be changed according to the left-right width of the winding-axis space 3K.

  As shown by a two-dot chain line in FIG. 5, the height of the winding shaft members 4 </ b> A and 5 </ b> A is configured so as to be substantially filled in the height direction of the winding shaft space 3 </ b> K. On the other hand, it is possible to reliably avoid displacement in the vertical direction.

  FIG. 7 shows a state in which the winding shaft members 4A and 5A are inserted into the winding shaft space 3K. In this way, by configuring the winding shaft members 4A and 5A provided in the insulating members 4B and 5B to be less than or equal to half the dimension of the power generating element 3 in the winding axis direction, the length exceeding the half of the dimension of the power generating element 3 in the winding axis direction When the winding member 4A and 5A are inserted, the other winding member 5A is placed in a direction perpendicular to the winding member insertion direction with respect to one winding member 4A so that they do not come into contact with each other. Work such as shifting the position becomes unnecessary.

  Then, as shown in FIG. 7, the power generation element 3 to which the insulating members 4 </ b> B and 5 </ b> B including the winding shaft members 4 </ b> A and 5 </ b> A are attached is accommodated in the case 2 and closed by the lid body 6. can do.

  In addition, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the summary of this invention.

  In the above-described embodiment, the insulating member 4B is formed of a U-shaped member having no bottom so that the insulation between the power generating element 3 and the bottom plate portion 2A of the case 2 is separated from another insulating plate 11 shown in FIG. However, as shown in FIGS. 8A, 8 </ b> B, and 8 </ b> C, a bottom plate portion 4 </ b> C may be provided at the lower end of the insulating member 4 </ b> B. In this case, the insulating plate 11 shown in FIG. 1 can be omitted.

  Moreover, in the said embodiment, although the structure which provided the insulating member for every electric power generation element was shown, as shown in FIG.8 (d), it is the structure which provided the one insulating member with respect to two electric power generation elements. There may be. In this case, two winding shaft members 4A and 4A are provided in one insulating member 4B.

  Moreover, in the said embodiment, although what provided the insulating members 4B and 5B which have the winding shaft members 4A and 5A in the both ends of the winding direction of the one electric power generation element 3, the winding shaft of one electric power generation element was shown. It can also comprise from what provided the insulating member which has a winding shaft member only in the one end side of a direction.

  Moreover, although the case where the long cylindrical winding type power generation element was used was shown in the said embodiment, it can also be implemented using a cylindrical winding type and the winding type power generation element of other arbitrary shapes. . Furthermore, although the non-aqueous electrolyte secondary battery has been described, the present invention can be similarly applied to other various secondary batteries and primary batteries.

  In the above embodiment, the type in which the winding member 4A is integrally formed with the insulating member 4B has been shown. However, the insulating member and the winding member can be separately manufactured and integrated. .

  Moreover, in the said embodiment, although insertion side front-end | tip 4T and 5T of winding shaft member 4A and 5A were made into circular arc shape, in addition to ellipse shape, the triangular shape rounded only at the front end, and polygonal shape, depending on the case, squares etc. Although it may be such a shape, there is an advantage that insertion into the winding shaft space can be performed more smoothly when the tip side is tapered.

  Moreover, in the said embodiment, after pinching the electric power generation element 3 with the clip 10, the collector 9 was connected and the structure of the retrofit type which ultrasonically welds was shown, However, after connecting a collector first Further, it may be a tipping type configuration in which ultrasonic welding is performed by sandwiching four clamping plates in four connection portions of the current collector.

  Moreover, in the said embodiment, although the type which is not provided with the core in the electric power generation element 3 was shown, this invention is applicable also to the electric power generation element provided with the core. In this case, the winding shaft member of the present invention is inserted inside the winding core.

DESCRIPTION OF SYMBOLS 1 ... Battery, 2 ... Case, 2A ... Bottom plate part, 3 ... Electric power generation element, 3K ... Coil space, 4A, 5A ... Coil member, 4B, 5B ... Insulation member, 4C, 5C ... Bottom plate part, 4T, 5T ... Insertion end, 6 ... Lid, 7 ... Positive electrode terminal, 8 ... Negative electrode terminal, 9 ... Current collector, 9A ... Connection part, 9B ... Main body part, 10 ... Clip, 10A, 10B ... Bending part, 10C ... Plate Part, 11 ... insulating plate

Claims (2)

In a battery in which a wound power generation element is housed in a case,
A winding shaft member inserted into a winding shaft space formed in a winding center portion of the power generation element is provided in an insulating member disposed at least at one end side in the winding shaft direction of the power generation element. battery.   The battery according to claim 1, wherein the insulating member is a U-shaped member that sandwiches an outer surface of the power generation element.

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