JP5248200B2 - Cell unit for battery pack and method of manufacturing battery pack - Google Patents

Description

  The present invention relates to a unit cell used in a battery pack in which an accessory is attached to one end of the unit cell, and a method of manufacturing a battery pack using the unit cell.

  Along with the recent thinning and downsizing of battery packs, battery packs in which positive electrode leads and negative electrode leads are taken from the sealing body side of the unit cells, and protective circuits and protective elements are concentrated on the sealing body side are becoming mainstream. For example, a protection circuit and a protection element are attached to a resin frame and stored in a cover.

  FIG. 5 shows an exploded perspective view of an example of a conventional battery pack. The battery pack 200 shown in this figure has a protection circuit 116 and a protection element 114 attached to a resin internal frame 113 and housed in a cover 117. The unit cell 100 is obtained by sealing the opening of a bottomed cylindrical outer can 101 containing an electrode body (not shown) with a sealing body 102.

  A can bottom cover 112 is attached to the lower part of the unit cell 100 via a double-sided tape 111. A resin internal frame 113 is attached to the upper part of the unit cell 100 via a double-sided tape 120. One end of the protection element 114 is joined to the negative electrode terminal 103 of the unit cell 100 by welding, and one end of the lead 115 is joined to the positive terminal 104 of the unit cell 100 by welding.

  The inner frame 113 supports a protection circuit 116, and the protection circuit 116 is joined to a lead 115 that is inserted through a slit formed in the inner frame 113 by welding. The protection element 114 and the protection circuit 116 are protection means for preventing overcharge, overcurrent, overdischarge, and the like.

  The cover 117 is fixed to the inner frame 113 by engaging the fixing claw 119 of the inner frame 117 with the hole 118 of the cover 117.

  As a result, the entire upper part of the unit cell 100 is covered with the cover 117. After the cover 117 is attached, a label (not shown) is wound around the outer peripheral surface of the unit cell 100.

  Here, in order to prevent a short circuit between the different electrodes of the unit cell, the sealing body side of the unit cell may be insulated. Patent Document 1 listed below describes an example of a configuration in which an insulating plate is attached to a lid (sealing body) of a unit cell.

  Moreover, the insulation of the sealing body side of a unit cell may be required at the time of conveyance of a unit cell. Specifically, in the manufacture of a battery pack, there may be a case where a unit manufacturing plant of a unit cell and a battery pack assembly plant in which an accessory is attached to the unit cell and completed as a battery pack are in different places.

  In this case, it is necessary to transport the unit cell completed at the unit cell manufacturing factory to the battery pack assembly factory. In order to ensure insulation on the side of the sealing body of the unit cell during transportation, an insulating sheet is attached to the sealing body.

FIG. 6A shows a perspective view of an example of a state where the adhesive-attached insulating sheet 121 is attached. As shown in the figure, an insulating sheet 121 with an adhesive is attached to the sealing body 102 in a unit cell manufacturing factory. This can prevent a short circuit between different electrodes of the unit cell during transportation.
JP 2006-40647 A

  However, the adhesive-attached insulating sheet 121 shown in FIG. 6A is necessary when transporting between factories, but is not necessary as a component of the battery pack in the example of the battery pack in FIG. In the example of FIG. 5, a double-sided tape 120 for bonding the internal frame 113 is required instead of the insulating sheet with adhesive 121.

  FIG. 6B shows a perspective view of an example of a state where the double-sided tape 120 is applied. It is difficult to completely peel off the adhesive-attached insulating sheet 121 once pasted from the sealing body 102. For this reason, as shown in FIG.6 (b), the double-sided tape 120 is affixed on the insulating sheet 121 with an adhesive, with the insulating sheet 121 with an adhesive remaining.

  FIG. 7 is a partially enlarged view after the internal frame 113 is bonded onto the insulating sheet with adhesive 121 via the double-sided tape 120. In this configuration, since the insulating sheet 121 with adhesive remains, the height of the upper part of the unit cell 100 is increased by the thickness of the insulating sheet 121 with adhesive, which is disadvantageous for downsizing.

  An object of the present invention is to solve the conventional problems as described above, and to provide a battery pack unit cell that is advantageous for miniaturization and a battery pack manufacturing method while ensuring insulation during transportation. And

In order to achieve the above object, a battery pack unit cell of the present invention is a battery pack unit cell in which an accessory is attached to one end, and an insulating sheet with an adhesive, wherein an adhesive is attached to the insulating sheet at one end. and is attached, wherein the insulating sheet is Ri peelable der from the adhesive during assembly of the battery pack, said insulating sheet is peeled from the pressure-sensitive adhesive, said accessory to said adhesive At least one is adhered .

  The battery pack manufacturing method of the present invention is a battery pack manufacturing method including a step of attaching an accessory part to one end of a unit cell, and the unit cell can peel an insulating sheet from an adhesive at the one end. An insulating sheet with an adhesive is pasted, and the insulating sheet is peeled off from the adhesive, and at least one of the accessory parts is bonded to the adhesive.

  According to the present invention, it is advantageous for miniaturization of the battery pack while ensuring insulation during transportation of the unit cell.

  According to this invention, when attaching an accessory to a unit cell, an insulating sheet can be peeled from an adhesive among the insulating sheets with an adhesive. Thereby, while ensuring the insulation of a unit cell at the time of conveyance, an accessory can be adhere | attached on the adhesive exposed by peeling of an insulating sheet at the time of attachment of an accessory. That is, since it is not necessary to affix a new adhesive when attaching the accessory, it is advantageous for downsizing the battery pack and an increase in manufacturing cost can be suppressed.

  In the battery pack unit cell of the present invention, a release agent is preferably applied to the pressure-sensitive adhesive side of the insulating sheet.

  Moreover, it is preferable that the edge part of the said insulating sheet has extended the said insulating sheet with an adhesive from the edge part of the said adhesive. According to this configuration, the pressure-sensitive adhesive can be more easily separated.

  Further, the unit cell is obtained by joining a sealing body to the opening of a bottomed cylindrical outer can having an opening at one end, and the insulating sheet with the adhesive is attached to the sealing body side. Preferably it is.

  In the method for producing a battery pack according to the present invention, the unit cell is transported to a place where the insulating sheet is peeled off from the adhesive with the adhesive insulating sheet attached. preferable.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is an exploded perspective view of a battery pack unit cell according to an embodiment of the present invention. FIG. 1A is a perspective view showing a state before the pressure-sensitive adhesive insulating sheet 5 is attached to the sealing body 2.

  The unit cell 10 is formed by sealing an opening of an outer can 1 containing an electrode body (not shown) with a sealing body 2. The unit cell 10 is, for example, a rectangular lithium ion battery, and is used for a mobile phone, a mobile device, or the like.

  The outer can 1 is a bottomed cylindrical body in which a substantially rectangular opening is formed at the upper end. The outer can 1 is formed, for example, by deep drawing a thin plate of aluminum or aluminum alloy. The sealing body 2 is a horizontally long member obtained by press-molding a thin plate of aluminum or an aluminum alloy, for example.

  The sealing body 2 is provided with a negative electrode terminal 3 via an insulator. The negative electrode terminal 3 is connected to a negative electrode current collecting lead (not shown) derived from the electrode body in the outer can 1. The sealing body 2 is connected to a positive electrode current collecting lead (not shown) derived from the electrode body in the outer can 1. Thereby, the whole sealing body 2 becomes a positive electrode. In the example of FIG. 1, a positive electrode terminal 4 formed of nickel or a nickel alloy is provided in order to ensure welding strength with a lead (nickel).

  The insulating sheet 5 with an adhesive is obtained by attaching an adhesive 7 to an insulating sheet 6. A release agent is applied to the pressure-sensitive adhesive 7 side of the insulating sheet 6. For this reason, the insulating sheet 6 can be easily peeled from the adhesive 7. Examples of the material of the insulating sheet 6 include PET, and examples of the release agent include a silicone release agent.

  FIG. 1 (b) shows a state where the insulating sheet 5 with the adhesive is attached to the sealing body 2. Since the insulating sheet 5 with adhesive has an opening corresponding to the negative electrode terminal 3 of the unit cell 1, the negative electrode terminal 3 is exposed from this opening. This is because one end of the protective element is later welded to the negative electrode terminal 3. Further, the adhesive 7 is not attached to the positive electrode terminal 4. This is because the lead is later welded to the positive terminal 4.

  The state of FIG. 1B is in a completed state for the unit cell 10. Attached parts such as a protection element, a protection circuit, and a cover are attached to the unit cell 10 to complete a battery pack. When the assembly factory of the battery pack is located in a place different from the manufacturing factory of the cell, it is necessary to transport the cell 10 to another factory.

  In FIG.1 (b), although the negative electrode terminal 3 is exposed, the sealing body 2 which is a positive electrode side is covered with the insulating sheet 5 with an adhesive. Thereby, the short circuit by conduction | electrical_connection with the positive electrode of the unit cell 1 and a negative electrode can be prevented at the time of conveyance.

  In FIG.1 (b), the insulating sheet 5 with an adhesive does not cover the whole sealing body 2, and the positive electrode terminal 4 is exposed. However, it is a short circuit between the negative electrode terminal 3 and its peripheral part that is likely to cause a short circuit during transportation. For this reason, if at least the periphery of the negative electrode terminal 3 is covered with the insulating sheet 5 with the adhesive, it is possible to prevent a short circuit during transportation.

  In addition, there is a configuration in which the positive electrode lead is not welded to the sealing body 2, and the positive electrode lead is welded to, for example, the bottom of the outer can 1 and the lead is led out to the upper portion of the outer can 1. In the case of such a structure, you may affix the insulating sheet 5 with an adhesive so that the whole sealing body 2 may be covered.

  FIG. 2 is a perspective view showing how the insulating sheet 6 is peeled off. At the time of transportation from the unit cell manufacturing factory to the battery pack assembly factory, the insulating sheet 6 plays the role of preventing a short circuit as described above. In the battery pack assembly factory, the adhesive 7 portion of the adhesive-attached insulating sheet 5 plays a role for adhering accessories. This will be described with reference to FIGS.

  FIG. 2 shows an enlarged view of the vicinity of the negative electrode terminal 3 and the positive electrode terminal 4 of FIG. As described above, since the release agent is applied to the pressure-sensitive adhesive 7 side of the insulating sheet 6, the insulating sheet 6 can be easily peeled off from the pressure-sensitive adhesive 7. In the example of FIG. 2A, the end portion of the insulating sheet 6 extends from the end portion of the adhesive 7. According to this configuration, the insulating sheet 6 can be more easily separated. Specifically, as shown in FIG. 2A, if the end portion of the insulating sheet 6 is lifted and this end portion is moved toward the other end portion, the insulating sheet 6 can be easily formed. Can be peeled off.

  FIG. 2B shows a state after the insulating sheet 6 is peeled off. The adhesive 7 is exposed after the insulating sheet 6 is peeled off. As a result, the accessory part can be bonded onto the adhesive 7. Therefore, in the battery pack assembly factory, it is not necessary to affix a new double-sided tape to affix the accessory parts.

  FIG. 3 is an exploded perspective view of the battery pack 20 according to the present embodiment. This figure shows an example of an accessory attached to the unit cell 10. These attachments are attached at the battery pack assembly factory. The unit cell 10 shown in FIG. 3 is in a state where the adhesive 7 is exposed through the peeling process shown in FIGS. 2 (a) and 2 (b).

  Hereinafter, attachment of the accessory will be described. A can bottom cover 12 is attached to the lower part of the unit cell 10 via a double-sided tape 11. A resin internal frame 13 is attached to the upper part of the unit cell 10. As described above, the adhesive 7 is exposed at the upper part of the unit cell 10. For this reason, the internal frame 13 can be bonded onto the adhesive 7 without newly attaching a double-sided tape to the upper part of the unit cell 10.

  One end of the protective element 14 is joined to the negative terminal 3 by welding, and one end of the lead 15 is joined to the positive terminal 4 by welding. The inner frame 13 supports a protection circuit 16, and the protection circuit 16 is joined to a lead 15 inserted through a slit formed in the inner frame 13 by welding. The protection element 14 and the protection circuit 16 are protection means for preventing overcharge, overcurrent, overdischarge, and the like.

  The cover 17 is fixed to the inner frame 13 by engaging the fixing claw 19 of the inner frame 13 with the hole 18 of the cover 17.

  As a result, the entire upper part of the unit cell 10 is covered with the cover 17. After the cover 17 is attached, a label (not shown) is wound around the outer peripheral surface of the unit cell 10.

  Next, the difference between the battery pack according to the present embodiment shown in FIG. 3 and the battery pack according to the conventional example shown in FIGS. The battery pack shown in FIG. 3 and the battery pack shown in FIG. 5 have the same configuration of the unit cell and its accessory parts. At the time of transporting a unit cell from a unit cell manufacturing plant to a battery pack assembly plant, conventionally, an insulating sheet 121 with an adhesive has been attached as shown in FIG. Since it is difficult to peel off the adhesive-attached insulating sheet 121, as shown in FIG. 6B, the adhesive double-sided tape 120 for the inner frame 113 (FIG. 5) is attached to the adhesive-attached insulating sheet 121. I pasted them on top of each other.

  On the other hand, in this embodiment, the point of attaching the insulating sheet with the adhesive during transportation is the same as the conventional one, but the insulating sheet 5 with the adhesive used in the present embodiment is the insulating sheet as described above. A release agent is applied to the pressure-sensitive adhesive 7 side of 6. For this reason, as shown to Fig.2 (a), (b), the insulating sheet 6 can be peeled.

  Therefore, in the present embodiment, it is not necessary to newly apply the double-sided tape 120 as in the conventional example of FIG. 6B, and the internal frame 13 (see FIG. 2) may be adhered.

  FIG. 4 shows a partially enlarged view after the inner frame 13 is bonded. As shown in the figure, the inner frame 13 is bonded to the upper part of the outer can 1 through the adhesive 7. FIG. 7 shows a partially enlarged view after bonding the internal frame 113 in the conventional example. In this configuration, an adhesive insulating sheet 121 and a double-sided tape 120 are interposed between the inner frame 113 and the upper portion of the outer can 101.

  Comparing the configuration of FIG. 4 with the configuration of FIG. 7, the height direction position of the inner frame 113 in FIG. 7 is equal to the thickness of the insulating sheet 121 with adhesive compared to the inner frame 13 in FIG. 4. You can see that it is only higher.

  Therefore, in the configuration of the present embodiment shown in FIG. 4, the height of the battery pack can be reduced by the thickness of the insulating sheet 121 with the adhesive, compared to the conventional configuration shown in FIG. This is advantageous for downsizing the pack. That is, according to the present embodiment, it is advantageous for miniaturization while ensuring the insulation of the unit cell during transportation. Moreover, since it is not necessary to add a new double-sided tape for bonding the internal frame 113, an increase in manufacturing cost can be suppressed.

  Note that the battery pack shown in FIG. 3 is merely an example, and any other configuration may be used as long as the battery pack is provided with a unit cell accessory attached with a double-sided tape. For example, the configuration in FIG. 3 is an example in which the internal frame 13 is bonded to the adhesive 7, but a configuration in which a protective element or a cover is bonded may be used.

  Further, when the insulating sheet portion of the insulating sheet with adhesive is required as a component of the battery pack, the insulating sheet may be used as an insulating material without peeling off.

  Moreover, although the said embodiment demonstrated the example which exists in the place where the manufacturing factory of a unit cell and the assembly factory of a battery pack differ, it is not restricted to this. That is, the present invention is useful when it is necessary to ensure the insulation of the unit cell during transportation of the unit cell even when the unit cell is manufactured and the battery pack is assembled in the same factory.

  As described above, according to the present invention, it is advantageous for miniaturization while ensuring insulation during transportation. Therefore, the present invention provides, for example, a method for manufacturing a battery pack used in a mobile phone or a mobile device, and these batteries. It is useful as a unit cell for a pack.

It is a disassembled perspective view of the unit cell for battery packs which concerns on one embodiment of this invention, (a) A perspective view which shows the state before affixing the insulating sheet 5 with an adhesive to the sealing body 2, (b) The figure is a perspective view showing a state in which the insulating sheet 5 with adhesive is attached to the sealing body 2. It is a perspective view which shows the mode of peeling of the insulating sheet 6 which concerns on one embodiment of this invention, (a) A figure is a perspective view at the time of the peeling start of the insulating sheet 6, (b) The figure peeled the insulating sheet 6 FIG. The disassembled perspective view of the battery pack which concerns on one embodiment of this invention. The elements on larger scale after adhere | attaching the internal flame | frame 13 in the structure of FIG. 3 which concerns on one embodiment of this invention. The exploded perspective view of an example of the conventional battery pack. (A) The figure is a perspective view of an example which affixes the conventional insulating sheet 121 with an adhesive, (b) A perspective view of an example which affixes the double-sided tape 120 on the insulating sheet 121, and affixes. The elements on larger scale after adhere | attaching the internal frame 113 in the structure of FIG. 5 which concerns on a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Exterior can 2 Sealing body 3 Negative electrode terminal 4 Positive electrode terminal 5 Insulating sheet with adhesive 6 Insulating sheet 7 Adhesive 10 Unit cell 13 Internal frame

Claims (6)

A battery pack battery with an accessory attached to one end,
At one end, an insulating sheet with an adhesive having an adhesive attached to the insulating sheet is attached,
The insulating sheet is Ri peelable der from the pressure-sensitive adhesive,
When assembling a battery pack, the battery pack unit cell is characterized in that the insulating sheet is peeled from the pressure-sensitive adhesive and at least one of the accessory parts is bonded to the pressure-sensitive adhesive .   The battery pack unit cell according to claim 1, wherein a release agent is applied to the pressure-sensitive adhesive side of the insulating sheet.   The battery pack unit cell according to claim 1, wherein the insulating sheet with the adhesive has an end portion of the insulating sheet extending from an end portion of the adhesive.   The unit cell is obtained by bonding a sealing body to the opening of a bottomed cylindrical outer can having an opening at one end, and the insulating sheet with an adhesive is attached to the sealing body side. Item 4. The battery pack unit cell according to any one of Items 1 to 3. A battery pack manufacturing method comprising a step of attaching an accessory part to one end of a unit cell,
The unit cell is obtained by attaching an insulating sheet with an adhesive capable of peeling an insulating sheet from an adhesive to the one end,
A method for producing a battery pack, comprising: peeling off the insulating sheet from the pressure-sensitive adhesive, and bonding at least one of the accessory parts to the pressure-sensitive adhesive.   The method for producing a battery pack according to claim 5, wherein the unit cell is transported to a place where the insulating sheet is peeled off from the adhesive with the insulating sheet with the adhesive attached.

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