JP2014179256A - Battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery pack which allows for positioning of a battery core pack in a cylindrical waterproof sheet having both open ends.SOLUTION: A battery pack includes a battery core pack housing a plurality of batteries while connecting, a waterproof sheet housing the battery core pack while sealing in a waterproof structure, and a charge terminal and a discharge terminal connected with the battery core pack via lead wires. The waterproof sheet is cylindrical and has openings at both ends, from which any one of the lead wire and the charge terminal or the lead wire and the discharge terminal is drawn. Furthermore, a retention welding portion for preventing a battery core pack arranged in the waterproof sheet from falling out of the opening at one end is provided on the side of the opening at one end, by welding the waterproof sheet.

Description

The present invention relates to a battery pack in which a plurality of batteries are stored in an outer case, and more particularly to a battery pack in which the batteries are stored in a case with a waterproof structure.

  For battery packs for outdoor use, it is necessary to store the batteries in a case as a waterproof structure. The battery pack in Patent Document 1 shown in FIG. 5 contains a battery core pack 20A containing a plurality of batteries, and a flexible waterproof sheet sealed in a waterproof structure in the form of a bag to contain the battery core pack 20A. The waterproof bag 90 is provided. The waterproof bag 90 has a cylindrical opening 90 </ b> A that welds or bonds one end of a flexible waterproof sheet formed into a cylindrical shape, and leads the lead wire 510 to the outside at the other end. A charge / discharge terminal 78 is connected to the tip of 510, and the battery core pack 20A and an external device can be electrically connected. Further, the opening 90A is provided with a welded portion 920 formed by welding the waterproof bag 90 along the outside of the lead wire 510, and an insertion gap 90E for drawing the lead wire 510 to the outside is provided. The insertion gap 90E is filled with the sealing agent 100, and the lead wire 510 is drawn out from the insertion gap 90E with a watertight structure. The battery pack stores the battery core pack 20A covered with the waterproof bag 90 in an exterior case.

JP2008-66000

  A waterproof bag in a conventional battery pack is formed into a bag shape with a configuration in which an opening at one end of a waterproof sheet formed in a cylindrical shape is welded and sealed, and the other end of the waterproof sheet is opened. Therefore, when the two terminals of the charge terminal and the discharge terminal connected to the battery core pack are located at both ends of the battery core pack, it is necessary to route one of the terminals to the opening at the other end, and the wiring is complicated. There is a problem of becoming. In addition, since the two terminals are pulled out from the opening at the other end, the number of lead wires inserted through the opening is increased, and the width of the insertion gap through which the lead wire is pulled out is increased. Arise. Moreover, since the amount of the sealing agent to be filled increases, there arises a problem that the weight of the battery pack increases. Therefore, it is possible to reduce the width of the insertion gap and improve waterproofness by opening both ends of the tubular waterproof sheet and pulling out the lead wire and charging terminal and the lead wire and discharging terminal from both openings, respectively. is there.

  However, since both ends of the cylindrical sheet are open, the battery core pack cannot be positioned and held in the waterproof sheet. For this reason, there is a problem that the posture of the waterproof sheet is restricted during the work of providing the welded portion in the opening of the waterproof sheet.

  Therefore, the present invention has been made to solve such a problem. Both ends of a cylindrical waterproof sheet are opened, and a lead wire and a charge terminal or a lead wire and a discharge terminal are respectively opened from both openings. The battery core pack can be positioned in the waterproof sheet at the same time as it is pulled out.

The battery pack of the present invention includes a battery core pack formed by connecting and storing a plurality of batteries, a waterproof sheet formed by sealing and storing the battery core pack in a waterproof structure, and a battery core pack via lead wires. It has a connected charging terminal and discharging terminal. The waterproof sheet has a cylindrical shape with openings at both ends, and the openings at both ends lead out the lead wire and the charge terminal or the lead wire and the discharge terminal, respectively. A holding welded portion that prevents the battery core pack housed in the waterproof sheet from coming out of the opening at one end, and an opening insertion portion for drawing out the lead wire and the charging terminal or the lead wire and the discharging terminal. Yes. Furthermore, the openings at both ends of the waterproof sheet are welded portions formed by welding the waterproof sheet along the outside of the lead wire, an insertion gap for drawing the lead wire to the outside, and a sealing agent filled in the insertion gap, respectively. It has.

  Moreover, the opening insertion part of the battery pack of this invention is taken as the magnitude | size which can insert a charge terminal or a discharge terminal.

  In the battery pack of the present invention, wiring can be simplified by opening both ends of a cylindrical waterproof sheet and drawing out a lead wire and a charge terminal and a lead wire and a discharge terminal from both openings. As a result, lead wires can be shortened and lead wire wiring space can be eliminated. In addition, by pulling out the lead wires of the charging terminal and the discharging terminal individually from both openings of the waterproof sheet, compared with the case where the lead wires of the charging terminal and the discharging terminal are pulled out from one opening together, The width of the gap can be reduced and the waterproofness can be improved. In the battery pack of the present invention, a holding weld portion is provided in the opening at one end, and the opening insertion portion that does not reach the holding weld portion is sized so that the charge terminal or the discharge terminal can be inserted. While the battery core pack is positioned and held in the waterproof sheet, one of the lead wire, the charging terminal, and the discharging terminal can be pulled out from the opening at one end.

It is a perspective view of the battery pack in an embodiment of the present invention. It is a disassembled perspective view of a battery pack. It is the perspective view which showed the battery core pack and the waterproof bag which showed the state before a battery core pack is accommodated in a waterproof sheet. It is the perspective view which showed the state by which the battery core pack was accommodated in the waterproof sheet, the welding part was formed in the opening part of the both ends of a waterproof sheet, and the lead wire was pulled out by the watertight structure. It is the perspective view which showed the state in which the battery core pack was accommodated in the waterproof bag in a prior art example.

  Embodiments of the present invention will be described below with reference to the drawings. However, the examples shown below exemplify battery packs for embodying the technical idea of the present invention, and describe the shape, dimensions, materials, etc. of the members. Is not specified as below.

The battery pack of the present invention is mainly mounted on an electric vehicle and supplies electric power to a driving motor. The present invention is used, for example, as a power source for assist bicycles, electric motorcycles, electric wheelchairs, electric tricycles, electric carts and the like. However, the present invention does not specify the use of the battery pack, and can also be used as a power source for various electric devices used outdoors such as electric tools.

The battery pack 12 of the present invention shown in FIGS. 1 and 2 is mainly mounted on an electronic device body and supplies power to the electronic device body. The battery pack 12 includes a battery core pack 2A configured by assembling three sets of battery blocks, a circuit board 4, a discharge terminal 7, and a charge terminal 8. The battery block stores and holds a plurality of cylindrical batteries 1 in a battery holder 3 including a pair of holder units 31. Further, the battery holder 3 has a plurality of batteries 1 provided with different electrodes at both ends in parallel postures and arranged in multiple stages and multiple rows. Further, the lead plate 5 is fixed to the end face of the battery holder 3 and connected to the end electrodes of the plurality of batteries 1 to connect the batteries 1 in series and in parallel. The plurality of batteries 1 are connected to a circuit board 4 on which a protection circuit is mounted via connection leads provided on the lead plate 5, and further, the circuit board 4, the charging terminal 8, and the discharging terminal via lead wires 51. 7 is electrically connected to the electronic device.

  The battery pack 12 of the present invention has the battery core pack 2A stored in the waterproof sheet 9 in order to improve the waterproof property and have a watertight structure. In particular, the battery core pack 2A is temporarily fixed in the waterproof sheet 9 Thus, the structure relates to a structure in which the lead wire 51, the discharge terminal 7, and the charge terminal 8 are drawn from the waterproof sheet 9.

  As shown in FIG. 2, the battery core pack 2 </ b> A has three sets of battery blocks 2 connected in a longitudinal direction, which is the longitudinal direction of the battery 1, and arranged linearly. In this battery core pack 2A, a plurality of batteries 1 are connected in parallel to increase the output current, and a plurality of batteries 1 are connected in series to increase the output voltage.

  A battery core pack 2 </ b> A shown in FIG. 2 includes three battery blocks 2. Each battery block 2 has an insertion tube portion of the battery 1 provided in the battery holder 3, the battery 1 is inserted into the insertion tube portion, and the battery 1 is disposed at a fixed position. The battery holder 3 of the battery block 2 includes a pair of holder units 31. The pair of holder units 31 are connected in the longitudinal direction, and the battery 1 is stored in an insertion cylinder provided in each battery holder 3. The three battery blocks 2 are arranged such that their end faces face each other with the insulating plate 6 interposed therebetween, and are connected in a direction along the longitudinal direction of the battery 1 housed in the battery block 2. The battery core pack 2A described above includes three battery blocks 2, but the battery pack 12 of the present invention can be configured with one or two battery blocks 2 as the battery core pack 2A. A structure in which the above battery blocks 2 are connected in the longitudinal direction can also be adopted.

  The insertion tube portion holds the battery 1 set therein in a fixed position. In the illustrated battery core pack 2A, the battery 1 is a cylindrical battery, and the insertion tube portion is shaped to hold the cylindrical battery inserted and held in place. However, the present invention does not necessarily specify the battery as a cylindrical battery, and the battery may be a square battery, for example. In a battery pack in which the battery is a rectangular battery, the insertion tube portion needs to be a rectangular tube shape. Moreover, although the battery 1 uses the lithium ion secondary battery, it can be set as all the batteries which can be charged, such as a lithium polymer battery, a nickel hydride battery, and a nickel cadmium battery.

  In the battery core pack 2A shown in FIG. 2, the three battery blocks 2 are each provided with a connection boss (not shown) and a connection hole 32 on each facing surface, and connected to the connection boss (not shown). By fitting the holes 32, the adjacent battery blocks 2 are fixed and positioned. Furthermore, the three sets of battery blocks 2 are provided with fitting ribs 33 and fitting recesses 34 so as to protrude from the opposing surfaces, and by connecting the fitting ribs 33 and the fitting recesses 34, Adjacent battery blocks 2 are connected.

  Further, as shown in FIG. 2, the battery core pack 2 </ b> A includes a circuit board 4 connected to the battery 1 housed in the battery block 2. The battery core pack 2A is arranged so as to straddle the side surfaces of the three sets of battery blocks 2 connected in a straight line. The circuit board 4 is housed in a board holder, and the circuit board 4 is disposed at a fixed position of the battery core pack 2A via the board holder. Further, an insulating plate 6 is disposed on the upper surface of the circuit board 4 in order to electrically protect electronic components mounted on the circuit board 4.

  Further, in the battery core pack 2A shown in FIG. 2, each lead plate 5 connected to a plurality of parallel units is connected to the circuit board 4 via connection leads. The circuit board 4 is mounted with a protection circuit (not shown) that controls charging / discharging of the battery 1. The circuit board 4 is mounted with an electronic component that realizes this protection circuit. The protection circuit also includes a circuit that detects the battery voltage of each battery 1 and cuts off the charge / discharge current. When any battery voltage becomes lower than the minimum voltage, this protection circuit switches off the switching element that cuts off the discharge current, and cuts off the discharge current. Further, when any battery voltage becomes higher than the maximum voltage, the switching element for stopping charging is switched off to stop charging. As described above, the battery core pack 2 </ b> A on which the protection circuit that controls charging / discharging by detecting each battery voltage is mounted can be used safely while protecting the battery 1. Further, the circuit board 4 is also mounted with a temperature detection circuit that detects a temperature abnormality of the battery 1. This temperature detection circuit detects that the temperature of the battery 1 detected by the temperature sensor rises abnormally, and controls the discharge and charge current of the battery 1 or stops charging and discharging. .

  A waterproof sheet 9 shown in FIG. 3 is a flexible sheet formed into a cylindrical shape. A plastic sheet can be used as the flexible sheet of the waterproof sheet 9. For the plastic sheet, polyimide (PI), polyethylene imide (PEI), polyethylene (PET) or the like can be used. These plastic sheets are characterized by excellent flexibility and heat resistance. Further, the electrolyte discharged when the safety valve of the battery 1 is opened does not melt or cause a chemical reaction. However, as the flexible sheet used for the waterproof sheet 9, other plastic sheets than those described above can be used. Moreover, since the waterproof sheet 9 is a permeable sheet, in FIG.3 and FIG.4, it describes so that a part of waterproof sheet 9 may permeate | transmit.

  The waterproof sheet 9 shown in FIG. 3 has a cylindrical shape with openings 9A at both ends, and includes a storage portion 9D for storing the battery core pack 2A between the openings 9A. Further, the openings 9A at both ends are configured to draw out either one of the lead wire 51 and the charge terminal 8 or the lead wire 51 and the discharge terminal 7, respectively. Accordingly, the waterproof sheet 9 stores the battery core pack 2A in the storage portion 9D, and the waterproof sheet 9 is connected to either the lead wire 51 and the charging terminal 8 or the lead wire 51 and the discharge terminal 7 from both openings of the waterproof sheet 9, respectively. 9 is pulled out. As shown in FIG. 3, the storage portion 9D of the waterproof sheet 9 is formed in a shape and size that can store the battery core pack 2A. The waterproof sheet 9 has a rectangular parallelepiped shape slightly larger than the outer shape of the battery core pack 2A so that the battery core pack 2A can be accommodated without difficulty. However, the waterproof bag is not limited to this shape, and the waterproof bag may be a cylindrical shape or an oval shape. It can also be cylindrical.

Further, as shown in FIG. 3, the battery core pack 2 </ b> A disposed in the housing portion 9 </ b> D of the waterproof sheet 9 is welded to the opening 9 </ b> A side of one end of the waterproof sheet 9. A pair of holding welds 91 that prevent the openings 9A from coming off are provided. The pair of holding welded portions 91 in FIG. 3 are arranged at both end edges of the waterproof sheet 9 so as to be along the direction orthogonal to the extending direction of the waterproof sheet 9 between the opening 9A at one end of the waterproof sheet 9 and the storage portion 9D. Each of them is formed from 9C toward the inside, and further extended toward the opening 9A at one end, and has an L shape with a predetermined width. Further, as shown in FIG. 3, when the holding welded portion 91 is formed from both end edges 9 </ b> C of the waterproof sheet 9 toward the inside along the width direction orthogonal to the extending direction of the waterproof sheet 9. An opening insertion portion 9B that is not related to the holding weld portion 91 is provided. The opening insertion portion 9B is formed in such a size that the battery core pack 2A is not inserted through the opening insertion portion 9B, and the charging terminal 8 and the discharge terminal connected to the battery core pack 2A via the lead wire 51. 7 is formed to have an opening width large enough to allow 7 to be inserted. Therefore, the holding core 91 provided on the opening 9A side of one end of the waterproof sheet 9 prevents the battery core pack 2A disposed in the prevention sheet storage portion 9D from coming out of the opening 9A on one end, The battery core pack 2A disposed in the storage portion 9D of the waterproof sheet 9 can be positioned in the storage portion 9D. The width of the holding weld 91 in this embodiment is
It is about 10 mm, and has an L shape having a dimension of about 90 mm in the extending direction of the waterproof sheet 9 and about 40 mm in the width direction perpendicular to the extending direction of the waterproof sheet 9.

  In the present embodiment, the shape of the holding weld portion 91 is L-shaped as shown in FIG. 3, but is not particularly limited to this shape, and the opening insertion portion 9 </ b> B formed by configuring the holding weld portion 91. The opening insertion portion is formed in such a size that the battery core pack 2A is not inserted through the opening insertion portion 9B, and the charging terminal 8 and the discharge connected to the battery core pack 2A via the lead wire 51. It suffices if the opening width is large enough to allow the terminal 7 to be inserted. In the present embodiment, the opening insertion portion 9 </ b> B is inserted with the discharge terminal 7 and the lead wire 51 connected to the discharge terminal 7.

  As shown in FIG. 4, the battery core pack 2A is disposed in the housing portion 9D of the waterproof sheet 9, and the discharge terminal 7 and the lead wire 51 are inserted through the opening insertion portion 9B provided on the opening 9A side of one end. The waterproof sheet 9 is pulled out. The charging terminal 8 and the lead wire 51 are drawn out from the opening 9A at the other end. Therefore, the lead wires 51 extending from both ends of the battery core pack 2A are drawn out from both openings 9A provided at both ends of the cylindrical waterproof sheet 9, and the leading ends of both lead wires 51 are connected to each other. The charging terminal 8 or the discharging terminal 7 is connected. Further, as shown in FIG. 4, a welded portion 92 is provided between the opening 9 </ b> A and the storage portion 9 </ b> D along the outer side of the both lead wires 51, and welded overlapping waterproof sheets 9. In this embodiment, the insertion gap 9 </ b> E is formed in the welded portion 92 along both outer sides of the lead wire 51. The lead wire 51 is led out from the both openings 9A of the waterproof sheet 9 through the insertion gap 9E. Further, the end of the welded portion 92 on the storage portion 9D side extends toward both end edges 9C of the waterproof sheet 9 along a direction orthogonal to the extending direction of the waterproof sheet 9, and is L-shaped. A welded portion 92 is formed. Therefore, as shown in FIG. 4, the L-shaped welds 92 are formed so as to face the openings 9 </ b> A at both ends of the waterproof sheet 9. The width of the welded portion 92 in this embodiment is about 10 mm, and has an L shape having a dimension of about 50 mm in the extending direction of the waterproof sheet 9 and about 50 to 100 mm in the width direction orthogonal to the extending direction of the waterproof sheet 9. It has a shape. Moreover, as shown in FIG. 4, the welding part 92 will be formed in the opening insertion part 9B in the opening part 9A side of the end of the waterproof sheet 9 in which the holding | wearing part for holding was formed.

In this embodiment, the L-shaped welded portion 92 is formed between the opening 9A and the storage portion 9D so as to face each other. However, the shape is not limited to this, and the opening 9A and An insertion gap 9E for pulling out the lead wire 51 from the opening 9A is formed between the storage section 9D and the structure other than the insertion gap 9E may be welded so as to form a watertight structure with the opening 9A.

  Further, the waterproof sheet 9 shown in FIG. 4 is filled with a sealing agent 10 such as silicone resin in the insertion gap 9E. Thus, the structure in which the sealing agent 10 is filled in the insertion gap 9E has a feature that the waterproof sheet 9 can be reliably waterproofed by pulling out the lead wire 51 from the insertion gap 9E in a watertight structure. With this configuration, the battery core pack 2A is disposed on the tubular waterproof sheet 9, and the lead wire 51, the discharge terminal 7, the lead wire 51, and the charge terminal 8 extending from both ends of the battery core pack 2A are connected to the waterproof sheet 9. It is possible to make it waterproof while having a configuration withdrawn to the outside. Further, the insertion gap 9E is formed by the welded portion 92 between the opening 9A and the storage portion 9D of the waterproof sheet 9, so that the entire opening 9A is filled as compared with the case where the sealing agent 10 is filled. The amount of the sealing agent 10 can be reduced.

The battery core pack 2A that is water-tightly covered with the waterproof sheet 9 is housed in the first case, and the charging terminal 8 and the discharge terminal 7 drawn out from both openings 9A of the waterproof sheet 9 are the first case. 11A is disposed at a predetermined position. Thereafter, as shown in FIG. 2, the first case 11A and the second case 11B are arranged on the outer case composed of the first case 11A and the second case 11B so that the first case 11A and the second case 11B face each other from both side surfaces of the battery core pack 2A. As a result, the battery core pack 2 </ b> A is accommodated to form a battery pack 12.

  The battery pack 12 shown in FIG. 1 is configured by fitting the second case 11B to the first case 11A. Further, the battery pack 12 shown in FIG. 1 has a structure in which the charging terminal 8 and the discharging terminal 7 are exposed so that the battery pack 12A can be connected to an external device, and the battery core pack 2A is waterproofed by a waterproof sheet 9.

  The outer case 4 is manufactured by molding plastic, but the material is not limited to plastic and may be a metal member such as aluminum in consideration of heat dissipation.

DESCRIPTION OF SYMBOLS 1 ... Battery 2 ... Battery block 2A, 20A ... Battery core pack 3 ... Battery holder 31 ... Holder unit 32 ... Connection hole 33 ... Fitting rib 34 ... Fitting recessed part 4 ... Circuit board 5 ... Lead board 51, 510 ... Lead wire 6 ... Insulating plate 7 ... Discharge terminal 8 ... Charge terminal 9 ... Waterproof sheet
9A, 90A ... Opening portion 9B ... Opening insertion portion 9C ... End edge 9D ... Storage portion 9E, 90E ... Insertion gap 91 ... Holding weld portion 92, 920 ... Welding portion 10, 100 ... Sealing agent 11A ... First case 11B ... First Two cases 12 ... Battery pack 78 ... Charge / discharge terminal 90 ... Waterproof bag

Claims (2)

A battery core pack formed by connecting and storing a plurality of batteries;
A waterproof sheet formed by sealing and storing the battery core pack in a waterproof structure;
It has a charge terminal and a discharge terminal connected to the battery core pack via lead wires,
The waterproof sheet has a cylindrical shape with openings at both ends, and the openings at both ends lead out the lead wire and the charging terminal or the lead wire and the discharge terminal, respectively.
A holding weld for welding the waterproof sheet to the opening at one end and preventing the battery core pack housed in the waterproof sheet from coming out of the opening at the one end; and the lead wire And the charging terminal or the lead wire and an opening insertion part for drawing out the discharging terminal,
Further, the opening portions at both ends of the waterproof sheet are respectively welded portions formed by welding the waterproof sheet along the outside of the lead wire, an insertion gap for leading the lead wire to the outside, and the insertion gap. A battery pack comprising a filled sealing agent. 2. The battery pack according to claim 1, wherein the opening insertion portion has a size capable of inserting the charging terminal or the discharging terminal.