JP2011049013A - Battery pack - Google Patents

Abstract

A heat dissipation plate is thermally coupled to the surface of a cylindrical battery in an ideal state to reduce a battery temperature difference. Even in the structure in which the cylindrical batteries are arranged in multiple stages and multiple rows, the short circuit of the battery by the heat radiating plate is effectively prevented and the safety is improved.
A battery pack includes a battery block 10 in which a plurality of rechargeable cylindrical batteries 1A are set in an insertion portion 21 of a battery holder 2 and arranged in multiple stages and multiple rows. The battery pack is connected to the battery holder 2 with a heat dissipation plate 8 that is thermally coupled to the surface of the cylindrical battery 1A. The heat radiating plate 8 has a metal plate formed into a corrugated shape in which U grooves 8A for fitting the cylindrical battery 1A are alternately provided on the opposite surface. In the battery pack, cylindrical batteries 1A arranged adjacent to each other are inserted into U grooves 8A on both surfaces of a heat radiating plate 8 made of a corrugated metal plate, and the outer peripheral surface of the cylindrical battery 1A is placed in the U groove 8A. It is thermally bonded to the inner surface.
[Selection] Figure 11

Description

  The present invention relates to a battery pack in which a large number of batteries are arranged in multiple rows and columns, and more particularly to a battery pack that is optimal as a power source for supplying a large amount of power to a traveling motor mounted on an electric vehicle such as an electric motorcycle.

  A battery pack used for high-power applications such as an electric motorcycle has a large number of batteries arranged in multiple stages and connected in series or in parallel. In this battery pack, a plurality of batteries are connected in series to increase the output voltage, and connected in parallel to increase the output current. A battery pack used for a high-power application is charged and discharged with a large current, and the temperature of the battery rises. The battery changes in electrical characteristics with temperature. Therefore, in a battery pack incorporating a large number of batteries, if there is a temperature difference between the batteries, the electrical characteristics are unbalanced due to the temperature difference. Battery imbalance accelerates the degradation of a particular battery and shortens the life of the entire battery pack. This is because there is a difference in remaining capacity due to an imbalance in electrical characteristics, and a specific battery is easily overcharged or overdischarged due to the difference in remaining capacity. Since the battery is promoted to be deteriorated by overcharge or overdischarge, when a specific battery is in this state, the battery deteriorates to shorten the life of the entire battery pack. In particular, a battery pack incorporating a large number of batteries has a plurality of batteries connected in blocks to form a battery block, and the plurality of battery blocks are housed in a battery case. This structure has a drawback that a temperature difference is easily generated in the battery block, and in particular, the battery temperature of the battery block arranged at the center of the battery case is increased.

  In order to eliminate this drawback, a battery pack has been developed in which a heat radiating plate is disposed in a thermally coupled state on the surface of the battery. (See Patent Document 1)

JP 2005-285456 A

  As shown in FIG. 1, the battery pack of Patent Document 1 has heat radiation plates 98 arranged along the surface of each battery on both surfaces of a cylindrical battery 91 arranged in parallel to the same horizontal plane. The heat dissipation plate 98 is connected to the battery holder 92 and disposed at a position where it is thermally coupled to the surface of the cylindrical battery 91. In this battery pack, the heat radiating plate 98 is thermally coupled to the plurality of cylindrical batteries 91 in a preferable state, so that the battery temperature difference can be reduced. However, the battery pack having this structure has a drawback that it is difficult to thermally couple the heat radiating plate 98 to the surface of the cylindrical battery 91 in an ideal state over a long period of time. This is because it is difficult for the battery holder 92 to always place the heat dissipation plate 98 in close contact with the battery surface. Moreover, since this battery pack arrange | positions a heat radiating plate on both surfaces of a cylindrical battery, in the structure where a cylindrical battery is arrange | positioned in a multistage multi-row, it adjoins a battery via a heat radiating plate which consists of a metal plate. Has the disadvantage of increasing the probability of shorting.

The present invention was developed for the purpose of solving the above-described drawbacks of the battery pack. An important object of the present invention is to provide a battery pack capable of reducing the temperature difference of the battery by thermally coupling the heat radiating plate to the surface of the cylindrical battery in an ideal state.
Another important object of the present invention is to provide a battery pack that can effectively prevent a short circuit of a battery by a heat radiating plate and increase safety even in a structure in which cylindrical batteries are arranged in multiple stages and multiple rows. is there.

Means for Solving the Problems and Effects of the Invention

  The battery pack of the present invention includes a battery block 10 in which a plurality of cylindrical batteries 1A that can be charged are set in an insertion portion 21 of a battery holder 2 and arranged in multiple stages and multiple rows. The battery pack is connected to the battery holder 2 with a heat dissipation plate 8 that is thermally coupled to the surface of the cylindrical battery 1A. The heat radiating plate 8 has a metal plate formed into a corrugated shape in which U grooves 8A for fitting the cylindrical battery 1A are alternately provided on the opposite surface. In the battery pack, cylindrical batteries 1A arranged adjacent to each other are inserted into U grooves 8A on both surfaces of a heat radiating plate 8 made of a corrugated metal plate, and the outer peripheral surface of the cylindrical battery 1A is placed in the U groove 8A. It is thermally bonded to the inner surface.

The above battery pack is characterized in that the temperature difference of the battery can be reduced by thermally coupling the heat radiating plate to the surface of the cylindrical battery in an ideal state. This is because the heat dissipating plate is used as a metal plate, and the metal plate is alternately formed into a corrugated shape having U-grooves on the opposite surface, and cylindrical batteries alternately adjacent to the U-grooves on both sides thereof are placed. This heat radiating plate can be brought into an ideal thermal coupling state by closely contacting the surface of the cylindrical battery with the restoring force of the corrugated metal plate or by restoring with time.
In the above battery pack, the heat radiating plates are alternately thermally coupled to both sides of the adjacent cylindrical batteries arranged in one row, and the heat radiating plates are not arranged on both surfaces of the cylindrical battery. Battery packs arranged in multiple stages and multiple rows also have a feature that can effectively prevent a short circuit of the battery due to the heat radiating plate and increase safety.

In the battery pack of the present invention, a plurality of heat dissipating plates 8 are connected to the battery holder 2, and cylindrical batteries 1 </ b> A housed in a multistage multi-row in the battery holder 2 are connected in series and in parallel with the lead plate 4. The cylindrical battery 1A formed by connecting the heat dissipating plates 8 in parallel with each other can be disposed in the U-groove 8A and thermally coupled.
In this battery pack, even if an outer can of the cylindrical battery thermally coupled to the heat radiating plate contacts the heat radiating plate, the cylindrical battery is not short-circuited by the heat radiating plate. This is because the cylindrical batteries that are thermally coupled to the heat radiating plates are connected in parallel and the outer cans have the same potential.

In the battery pack of the present invention, the battery holder 2 is formed of an insulating material, and a slit 20 is provided to place the heat radiating plate 8 in a fixed position, and the heat radiating plate 8 is inserted into the slit 20 and arranged in a fixed position. be able to.
This battery pack can be placed on the battery holder simply and easily by inserting the heat dissipation plate into the slit of the battery holder so as not to be displaced.

In the battery pack according to the present invention, the battery holder 2 is constituted by a pair of holder units 2A divided into two, and the end portions of the respective cylindrical batteries 1A are inserted into the insertion portions 21 of the separated holder units 2A. And can be placed in a fixed position. Further, in the battery pack, each holder unit 2 </ b> A has a slit 20 that opens to the opposing surface, and the heat dissipation plate 8 can be inserted into the slit 20 to connect the heat dissipation plate 8 to the battery holder 2. .
The battery pack can be connected so that the heat radiating plate is not detached from the battery holder by connecting the holder unit. For this reason, the heat dissipation plate can be easily connected to the battery holder so as not to be detached.

It is a perspective view of the conventional battery pack. It is a perspective view of the battery pack concerning one Example of this invention. It is the III-III sectional view taken on the line of the battery pack shown in FIG. FIG. 4 is a sectional view of the battery pack shown in FIG. 2 taken along the line IV-IV. FIG. 3 is an exploded perspective view of the battery pack shown in FIG. 2. FIG. 6 is a bottom perspective view of the battery pack shown in FIG. 5. FIG. 3 is an exploded perspective view of a battery case, a battery block, and a connection plate of the battery pack shown in FIG. 2. It is a perspective view of a battery block. It is a vertical longitudinal cross-sectional view of the battery block shown in FIG. It is a disassembled perspective view of the battery block shown in FIG. It is a disassembled perspective view of the battery holder of the battery block shown in FIG. It is a disassembled perspective view which shows the connection structure of a holder unit, a thermal radiation plate, and a battery. It is the XIII-XIII sectional view taken on the line of the battery block shown in FIG. It is the front view which looked at the holder unit of the battery holder shown in FIG. 11 from the inner side. It is a perspective view of a battery case. It is a bottom perspective view of a connection plate.

  Embodiments of the present invention will be described below with reference to the drawings. However, the embodiment described below exemplifies a battery pack for embodying the technical idea of the present invention, and the present invention does not specify the battery pack as follows.

  Further, in this specification, in order to facilitate understanding of the scope of claims, numbers corresponding to the members shown in the examples are indicated in the “claims” and “means for solving problems” sections. It is added to the members. However, the members shown in the claims are not limited to the members in the embodiments.

  The battery pack of the present invention is mainly mounted on an electric motorcycle and supplies electric power to a running motor. In particular, the present invention has a large number of batteries arranged in multiple stages and multiple rows to increase the output, and is therefore optimal for high output applications such as electric vehicles. Therefore, the battery pack of the present invention is optimal as a power source for electric vehicles such as electric motorcycles, assist bicycles, electric wheelchairs, electric tricycles, and electric carts. Hereinafter, although the battery pack used for an electric motorcycle is explained in full detail as an Example, this invention does not specify the use of a battery pack to an electric motorcycle.

  In the battery pack of FIGS. 2 to 7, a plurality of batteries 1 are arranged in a multistage multi-row with a battery holder 2 to form a battery block 10, and the plurality of battery blocks 10 are housed in a battery case 3. In the illustrated battery pack, three battery blocks 10 are arranged in three rows and stored in a battery case 3 in a parallel posture.

  As shown in FIGS. 8 to 13, the battery block 10 includes a plurality of batteries 1 that can be charged, and battery holders 2 in which the batteries 1 are arranged in multiple rows and columns in parallel postures. Further, the battery block 10 shown in the figure includes a circuit board 5 connected to the battery 1 via a lead plate 4, and the circuit board 5 is disposed at a fixed position of the battery holder 2.

  The battery 1 is a rechargeable secondary battery and is a lithium ion secondary battery. However, the battery may be a nickel metal hydride battery or a nickel cadmium battery. Further, in the battery pack shown in the figure, the battery 1 is a cylindrical battery 1A. In the illustrated battery block 10, the batteries 1 are arranged in multiple rows and columns in parallel postures, and are held in place by the battery holder 2 so that the end faces of the batteries 1 are positioned on the same plane. The battery block 10 shown in the figure has a plurality of batteries 1 in a parallel posture, 10 batteries 1 in a single row are arranged in 10 rows in a parallel posture, and these are arranged in six rows, for a total of 60 batteries 1. Is arranged. That is, this battery block 10 has the batteries 1 arranged in 6 rows and 10 rows. In the illustrated battery block 10, the vertically adjacent batteries 1 are arranged in a valley, and the batteries 1 in each row are arranged in a zigzag shape. In the illustrated battery block 10, the batteries 1 are arranged in 6 rows and 10 rows, but the present invention does not specify the number or arrangement of the batteries included in the battery block as shown in the figure.

  Further, in the battery pack of FIGS. 3 to 5 and 7, three battery blocks 10 are housed in the battery case 3. Therefore, this battery pack includes 180 batteries 1 in total. However, the battery pack of the present invention does not specify the number of battery blocks accommodated in the battery case, and these are set to the optimum number for the application.

  The plurality of batteries 1 are connected to each other in series and in parallel by welding a lead plate 4 to the end face. The lead plate 4 connects the batteries 1 in the same stage in series, and connects the batteries 1 in the same row arranged in a zigzag shape in parallel. The lead plate 4 is a metal plate and is welded to the end electrode of the battery 1 to connect the batteries 1 in the same row in parallel. In the battery block 10 of FIGS. 8 to 11, the batteries 1 in the same row are arranged in a zigzag shape, so that the lead plate 4 is also in a zigzag shape. The lead plate 4 that connects the batteries 1 in the adjacent rows in series is zigzag-shaped, and the lateral width is set to be a width that is connected to the batteries 1 in the two rows. The battery block 10 of FIG. 10 has the lead plate 4 and 10 batteries 1 connected in series and 6 batteries 1 connected in parallel. In other words, the 60 batteries 1 are connected in a 10-by-6 manner with the lead plate 4. The battery pack can adjust the output voltage by the number of batteries 1 connected in series, and can adjust the output current by the number of batteries 1 connected in parallel. Since the battery block 10 shown in the figure connects ten batteries 1 in series, the output voltage is 10 times the battery voltage. Therefore, the output voltage of the battery block 10 using the lithium ion battery having a rated voltage of 3.7V is 37V.

  In the illustrated battery block 10, each lead plate 4 is connected to a circuit board 5 fixed to the battery holder 2. This is because a protection circuit (not shown) mounted on the circuit board 5 detects the voltage of each battery 1. The lead plate 4 is provided with a connecting portion 4A connected to the circuit board 5 so as to protrude from the end portion. The lead plate 4 has a lead wire 6 connected to the connecting portion 4A, and is connected to a protection circuit of the circuit board 5 through these.

  As shown in FIGS. 9, 11, 12, and 14, the battery holder 2 is provided with an insertion portion 21 into which a battery 1 is inserted and arranged at a fixed position, which is partitioned by a partition wall 22. In the illustrated battery block 10, since the battery 1 is a cylindrical battery 1 </ b> A, the insertion portion 21 of the battery holder 2 has a cylindrical shape along the surface of the battery 1. The battery holder 2 is arranged in a fixed position by inserting the battery 1 into the insertion portion 21. The battery holder 2 is manufactured by molding an insulating plastic. Since the battery block 10 shown in the figure includes 60 batteries 1, the battery holder 2 is integrally formed of plastic as a shape in which 60 insertion parts 21 are provided by partition walls 22. The insertion portion 21 has both ends opened so that the end electrode of the battery 1 inserted therein can be exposed to the outside.

Further, in the battery holder 2 in FIGS. 9 and 14, the partition wall 22 is thicker at the center than at the surface. In the battery holder 2, the thickness of the partition wall 22 varies depending on the part, and the thickness of the partition wall 22 is the thinnest at the part where the surface of the adjacent cylindrical battery 1 </ b> A is closest. In the battery holder 2, the thickness of the thin portion 22 a that is the thinnest is made thicker than the surface portion at the central portion of the battery holder 2. The battery holder 2 of FIG. 14 gradually increases the thickness of the thin wall portion 22a of the partition wall 22 from the surface toward the center, t ₁ = 1.5 mm, t ₂ = 2.0 mm, t ₃ = 2.5 mm, t ₄ = It is changed to 3.0 mm. In this battery block 10, the thin wall portion 22 a of the partition wall 22 is thickened toward the central stage of the batteries 1 arranged in multiple stages, but the thin wall portion 22 b of the partition wall 22 in the same stage has the same thickness. However, in the battery pack, the partition at the same stage of the battery holder can be thicker at the center than at both ends.

  The battery holder 2 in which the thickness of the partition wall 22 at the center of the battery holder 2 is thicker than that of the surface portion is such that the heat capacity of the partition wall 22 that is thermally coupled to the battery 1 disposed at the center is set to the surface portion of the battery holder 2. It can be made larger than the partition wall 22 formed by thermal coupling to the battery 1 arranged in the above. This is because the heat capacity is specified by the product of the volume of the partition wall 22 and the specific heat. The partition wall 22 having a large heat capacity can reduce the temperature rise with respect to the heat energy absorbed from the battery 1. Therefore, by making the heat capacity of the partition wall 22 thermally coupled to the battery 1 disposed in the center portion larger than that of the partition wall 22 thermally coupled to the battery 1 disposed on the surface portion, the battery holder 2 The temperature rise of the battery 1 arranged in the central portion can be further reduced. Since the battery holder 2 radiates heat from the surface to the outside, the temperature of the battery 1 on the surface portion tends to decrease. In other words, the battery temperature at the center tends to increase. However, the battery holder 2 in which the heat capacity of the central partition 22 is increased can increase the thermal energy absorbed by the central partition 22 from the battery 1, thereby reducing the temperature rise of the central battery 1. For this reason, the temperature difference of the battery 1 arrange | positioned at the surface part and center part of the battery holder 2 can be decreased. However, in the battery pack of the present invention, it is not always necessary to make the wall thickness of the partition wall of the battery holder thicker at the center than at the surface. In the battery holder, all the partition walls can be made equal in thickness.

  Further, the battery holder 2 shown in the figure is divided into two pairs of holder units 2A in order to smoothly insert a large number of batteries 1 into the insertion portion 21 without a gap. The battery holder 2 is disposed at a fixed position by inserting the end portions of the respective batteries 1 into the insertion portions 21 of the separated holder units 2A. Each holder unit 2A is provided with an insertion portion 21 into which almost half of the battery 1 can be inserted, and one battery 1 is inserted into the pair of holder units 2A and arranged at a fixed position.

  Further, the battery block 10 is connected to the battery holder 2 with a heat radiating plate 8 that is thermally coupled to the surface of the cylindrical battery 1A. As shown in FIGS. 9, 11, and 12, the heat radiating plate 8 is formed of a metal plate having a corrugated shape in which U grooves 8 </ b> A for fitting the cylindrical batteries 1 </ b> A are alternately provided on the opposite surface. This battery block 10 is formed by alternately inserting cylindrical batteries 1A arranged adjacent to each other in U-grooves 8A on both surfaces of a heat radiating plate 8 made of a corrugated metal plate. It is thermally coupled to the inner surface of the groove 8A.

  As shown in FIGS. 9 and 12, the heat radiating plate 8 is a metal plate having a waveform formed by connecting a plurality of U-grooves 8A curved in a shape along the outer periphery of the cylindrical battery 1A by a linear connecting portion 8B. Is molded. The heat radiating plate 8 shown in the drawing is arranged at a fixed position in a state where cylindrical batteries 1A arranged adjacent to each other on both surfaces of the connecting portion 8B are fitted into U-grooves 8A provided on the opposite surface. The heat radiating plate 8 in FIG. 9 is formed so that each U-groove 8A has a semicircular shape, and its inner surface faces an area of about 50% of the outer periphery of the cylindrical battery 1A. The heat radiating plate 8 thermally couples the inner surface of the U-groove 8A with a large area in contact with the surface of the cylindrical battery 1A, and efficiently conducts the heat of the cylindrical battery 1A so that the temperature difference of the battery 1 is reduced. Less. Furthermore, the heat radiating plate 8 of FIG. 11 is disposed at the center of the cylindrical battery 1A, with the axial width of the cylindrical battery 1A being approximately half the total length of the cylindrical battery 1A. However, the width of the heat dissipation plate can be 20% to 90%, preferably 30% to 80% of the total length of the cylindrical battery. If the width of the heat dissipating plate is widened, the area in contact with the cylindrical battery becomes large. Therefore, the heat generated from the battery can be efficiently conducted and the battery temperature can be made uniform quickly, but the manufacturing cost increases. On the contrary, if the width of the heat radiating plate is narrowed, the manufacturing cost can be reduced, but the area in contact with the cylindrical battery is reduced, and the efficiency of conducting the heat generation of the battery is lowered. Therefore, the width of the heat radiating plate is set to the above-mentioned range in consideration of these matters. The heat radiating plate 8 described above is formed by bending a metal plate into a predetermined shape. An aluminum plate is used for this metal plate. However, an iron plate, a copper plate, a Shinchu plate, etc. can be used for the metal plate. The heat radiating plate 8 can be brought into an ideal thermal coupling state by bringing the surface thereof into close contact with the surface of the cylindrical battery 1A by restoring the metal plate processed into a corrugated shape or by restoring it with time. .

  In the battery block 10 of FIGS. 9 to 11, a plurality of heat dissipation plates 8 are connected to the battery holder 2. Each of the heat radiating plates 8 is thermally coupled by arranging cylindrical batteries 1A formed in parallel with each other by lead plates 4 in the U-groove 8A. In the battery block 10 shown in the figure, 60 batteries 1 are connected in a series of 10 to 6 with lead plates 4. Accordingly, six cylindrical batteries 1A arranged adjacent to each other in the figure and connected in parallel are arranged in the U groove 8A of one heat radiating plate 8 and thermally coupled. Since this battery block 10 is connected in parallel with each other and the cylindrical battery 1A having the same potential as the outer can is thermally coupled to the heat dissipation plate 8, the heat dissipation plate 8 does not cause the cylindrical battery 1A to be short-circuited. Furthermore, since the partition walls 22 are arranged between the cylindrical batteries 1A and the heat radiating plates 8 arranged in rows adjacent to each other and insulated from each other, they do not directly contact and short-circuit.

  Further, the battery holder 3 is provided with a slit 20 for disposing the heat radiating plate 8 at a fixed position. The battery holder 3 shown in FIGS. 9 and 12 is provided with a slit 20 in a partition wall 22 located between cylindrical batteries 1A connected in parallel to each other. The battery holder 3 shown in the figure has slits 20 provided in the partition wall 22 communicating with the insertion portions 21 adjacent to each other. The connection portions 8B of the heat dissipation plate 8 are inserted into the slits 20 and the adjacent insertion portions 21 are inserted. The U-groove 8A of the heat radiating plate 8 is inserted into the heat sink plate 8. The battery holder 2 composed of a pair of holder units 2A is provided with slits 20 that open on the opposing surfaces of the respective holder units 2A. The battery holder 2 is disposed at a fixed position of the battery holder 2 with the heat dissipation plate 8 inserted into the slit 20 and the insertion portion 21.

  As shown in FIG. 12, the battery holder 2 has a heat radiating plate 8 disposed at the center of the cylindrical battery 1A, and both ends thereof are inserted into the opposed insertion portions 21 and slits 20 of the pair of holder units 2A. The heat radiating plate 8 is disposed at a fixed position. The holder unit 2 </ b> A is provided with an insertion recess 21 </ b> A in which both ends of the heat dissipation plate 8 can be fitted on one side of the inner surface of the insertion part 21. The insertion recess 21 </ b> A has a width that is substantially half of the entire length of the heat dissipation plate 8, and the depth of the recess is substantially equal to the thickness of the heat dissipation plate 8. Further, the depth of the slit 20 provided in the partition wall 22 is also approximately half the depth of the entire length of the heat dissipation plate 8. As a result, the heat radiating plate 8 is configured so that both end portions can be inserted almost half by half into the opposing insertion portion 21 and slit 20 of the pair of holder units 2A. The battery holder 2 can be connected so that the heat radiating plate 8 is not detached from the battery holder 2 by connecting the pair of holder units 2A. For this reason, the heat radiation plate 8 can be easily connected to the battery holder 2 so as not to be detached.

  In the battery block 10 described above, both end portions of each heat radiating plate 8 are inserted into the insertion portions 21 and the slits 20 of the pair of separated holder units 2A and arranged at fixed positions, and each cylindrical battery 1A has a fixed position. Both end portions are inserted into the insertion portions 21 of the separated pair of holder units 2 </ b> A, and the cylindrical battery 1 </ b> A is inserted into the U groove 8 </ b> A of the heat radiating plate 8. In this state, each cylindrical battery 1 </ b> A is thermally coupled at its outer peripheral surface to the inner surface of the U groove 8 </ b> A of the heat radiating plate 8. The cylindrical battery 1A inserted into the insertion portion 21 of the battery holder 2 and thermally coupled to the inner surface of the U groove 8A of the heat radiating plate 8 is thermally coupled to the partition wall 22 directly or via the heat radiating plate 8. The battery holder 2 conducts heat from the battery 1 directly to the partition wall 22 to dissipate heat, or conducts heat from the heat dissipation plate 8 to the partition wall 22 to dissipate heat.

  3 and 4, the battery block 10 is put in the battery case 3 and the battery block 10 is embedded in the potting resin 7. The potting resin 7 can completely embed all the batteries 1 and thermally bond each battery 1 to the battery case 3 in an ideal state. However, it is not necessary for potting resin 7 to completely embed all batteries 1. For example, a part of the uppermost battery can be brought into contact with potting resin. The battery pack filled with the potting resin 7 is filled with the potting resin 7 between the insertion portion 21 of the battery holder 2 and the battery 1 and between the insertion portion 21 and the heat dissipation plate 8. In addition, the thermal coupling between the heat radiating plate 8 and the battery holder 2 can be made more ideal, and the thermal coupling between the battery 1 and the battery case 3 can be made ideal. In order to smoothly fill the insertion portion 21 of the battery holder 2 with the paste-like potting resin 7 without a gap, the battery holder 2 shown in FIGS. 8, 10 and 11 is a relative connection of a pair of holder units 2A. A gap connector 23 for specifying the position is provided.

  The gap connector 23 has a structure in which a pair of holder units 2A are connected to each other by providing an inflow gap 24 through which the potting resin 7 passes. The gap connector 23 is provided with an inflow gap 24 of, for example, 1 mm to 10 mm, preferably 2 mm to 8 mm, and more preferably 3 mm to 6 mm on the opposing surfaces of the pair of holder units 2A to connect the holder units 2A. The gap connector 23 shown in FIG. 13 is a connecting boss 23X provided so as to protrude from the opposing surfaces of the pair of holder units 2A. The gap connector 23, which is the connecting boss 23X, is integrally formed on the plastic holder unit 2A. One connecting boss 23X has a cylindrical connecting convex portion 23a at the tip, and the other connecting boss 23X has a connecting cylinder portion 23b into which the connecting convex portion 23a is inserted. In this gap connector 23, the connecting projection 23a of one connecting boss 23X is inserted into the connecting cylinder part 23b of the other connecting boss 23X, and an inflow gap 24 is provided and connected to the pair of holder units 2A. The holder unit 2A is provided with connecting bosses 23X at the four corners of the opposing surface. The connection bosses 23X are provided at a plurality of locations of the holder unit 2A, and connect the holder units 2A with the inflow gap 24. The interval of the inflow gap 24 can be specified by the protruding amount by which the connecting boss 23X protrudes from the opposing surface of the holder unit 2A. That is, the protruding amount of the connecting boss 23X is set to a height at which the connecting protrusion 23a is inserted into the connecting cylinder portion 23b and a predetermined inflow gap 24 is formed.

  The pair of holder units 2A connected via the gap connector 23 can smoothly fill the potting resin 7 filled in the battery case 3 from the inflow gap 24 to the insertion portion 21 without gaps. In particular, the potting resin 7 can be filled without a gap between the battery 1 and the insertion portion 21 in a state where the elongated battery 1 is inserted into the insertion portion 21.

  Furthermore, the holder unit 2A has an inner shape of the insertion portion 21 from the facing surface side where the inflow gap 24 is provided toward the end so that the outer shape of the battery 1 can be confirmed by the dotted line in FIG. In other words, the insertion portion 21 can be filled more smoothly with the potting resin 7 flowing from the inflow gap 24 by making the inner shape of the insertion portion 21 of the battery holder 2 tapered from the center to both ends. The insertion portion 21 in which the cylindrical battery 1 is arranged at a fixed position has an inner shape of a columnar shape, and the inner diameter is reduced from the central portion of the insertion portion 21 toward both ends so that the inner diameter of both ends is substantially equal to the outer diameter of the battery 1. Equally, the battery 1 is held in place exactly. In addition to being able to fill the potting resin 7 smoothly, the insertion portion 21 can smoothly insert the battery 1 into the insertion portion 21 of each holder unit 2A. Moreover, in the state which inserts the battery 1, both ends of the battery 1 can contact the inner surface of the insertion part 21, and the battery 1 can be hold | maintained in a fixed position.

  Furthermore, as shown in FIG. 9, the battery holder 2 that fills the insertion portion 21 with the potting resin 7 can be provided with a filling groove 25 extending in the longitudinal direction of the battery 1 on the inner surface of the insertion portion 21. The filling grooves 25 are provided in a plurality of rows on the inner surface of the insertion portion 21. The battery holder 2 can be filled more smoothly into the gap between the inner surface of the insertion portion 21 and the battery 1 by pouring the paste-like potting resin 7 filled from the inflow gap 24 between the holder units 2A into the filling groove 25. .

  Furthermore, the battery holder 2 is positioned at the openings provided at both ends of the insertion portion 21 and the lead plate 4 is disposed. The lead plate 4 is fixed to the battery end surface exposed from the opening of the insertion portion 21 by welding on the outside of the insertion portion 21. The battery holder 2 shown in FIGS. 9 and 11 has a positioning recess 26 into which the lead plate 4 is inserted at the opening end of the insertion portion 21. The lead plate 4 is inserted into the positioning recess 26 and placed at a fixed position. is doing. The positioning recess 26 has an outer shape slightly larger than the outer shape of the lead plate 4, and the lead plate 4 is placed in a fixed position.

  As shown in FIG. 13, the battery holders 2 that are divided and formed are connected to each other by screwing a set screw 19 into an integrally formed connection boss 23X. The battery holder 2 in FIG. 11 is provided with a connecting boss 23X integrally formed on the outer periphery. The connecting boss 23X has a cylindrical shape, and a set screw 19 is inserted inside. However, although not shown, the divided battery holders can be connected by a locking structure, or can be connected by bonding, or can be connected in combination.

  The battery holder 2 described above is divided into two and molded from plastic, but the battery pack of the present invention does not specify the battery holder as described above. The battery holder can have any other structure that allows a plurality of batteries and a heat dissipating plate to be placed in a fixed position by inserting them into the insertion portion. The battery holder can be, for example, a whole structure without being divided, or can be divided into two or more parts. Moreover, the battery pack of this invention does not necessarily embed a battery in potting resin.

  The battery block 10 of FIGS. 8 and 9 has a circuit board 5 connected to the upper surface. As shown in the figure, the battery block 10 with the battery 1 in a horizontal posture has a circuit board 5 arranged in a horizontal posture on the upper surface of the battery holder 2. The battery holder 2 shown in the figure is provided with a holder portion 27 for guiding the circuit board 5 to a fixed position. The battery holder 2 shown in the drawing is integrally formed with positioning ribs 28 protruding upward along the outer periphery of the upper surface, and a holder portion 27 is provided. The battery holder 2 shown in the drawing is on the upper surface of each holder unit 2A along the outer peripheral edge excluding the opposite sides so that the circuit board 5 can be disposed on the upper surface in a state where the pair of holder units 2A are connected. Positioning ribs 28 are provided. The holder portion 27 has a planar shape of the positioning rib 28 along the outer periphery of the circuit board 5 so that the circuit board 5 can be guided to the inside of the positioning rib 28 and placed in a fixed position. Furthermore, the battery holder 2 shown in the figure is provided with a connecting boss 29 protruding from the upper surface, and the circuit board 5 is fixed to the connecting boss 29 via a set screw 18 to attach the circuit board 5 to the battery. It is arranged at a position away from the upper surface of the holder 2. On this circuit board 5, an electronic component (not shown) that realizes a protection circuit or the like can be arranged on the surface facing the battery holder 2. However, although not shown, the circuit board can be fixed to the battery holder with a locking structure.

  Further, the battery holder 2 shown in the drawing is provided with a notch 28 </ b> A for pulling out the lead wire 6 fixed to the circuit board 5 to the outside of the circuit board 5 on the positioning ribs 28 facing both side edges of the circuit board 5. . The cutout portion 28 </ b> A is provided at a position facing the lead wire 6 fixed to the circuit board 5. The battery holder 2 is arranged without projecting the upper end of the lead wire 6 above the upper end of the positioning rib 29 by guiding the lead wire 6 drawn out from both sides of the circuit board 5 to the notch 28A. ing. The lead wire 6 drawn out of the circuit board 5 at the notch 28 </ b> A is connected to the connection part 4 </ b> A of the lead plate 4, and the lead plate 4 is connected to the circuit board 5.

  The circuit board 5 is connected to the battery 1 via the lead wire 6 and the lead plate 4. The circuit board 5 is mounted with a circuit (not shown) for detecting the battery voltage and controlling charging / discharging of the plurality of batteries 1 and a protection circuit (not shown) for cutting off the charging / discharging current. Yes. When any battery voltage becomes lower than the minimum voltage, the protection circuit switches off the switching element that cuts off the discharge current to cut 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 pack in which the protection circuit for detecting the battery voltage and controlling the charge / discharge is mounted can be used safely while protecting the battery 1. Furthermore, the circuit board 5 is also mounted with a temperature detection circuit that detects a temperature abnormality of the battery 1. The temperature detection circuit of the circuit board 5 detects that the battery 1 has risen to an abnormal temperature, and controls the discharge and charge current of the battery 1 or stops charging and discharging.

  The battery case 3 is manufactured by molding plastic. The battery case 3 of FIGS. 3 to 7 and FIG. 15 is formed in a box shape having an upper opening. The battery case 3 is provided with a hollow partition wall 32 between the adjacent battery blocks 10 and having a hollow portion 33 open to the surface of the battery case 3 between the adjacent battery blocks 10. 10 is arranged in a thermally coupled state. The hollow partition wall 32 is substantially equal to the height of the battery block 10, for example, is higher than 80% of the height of the battery block 10, and is thermally coupled to almost the entire side surface of the battery block 10, so Is radiating heat. Both ends of the hollow partition wall 32 are connected to the inner surface of the battery case 3 and are connected to opposite side walls 34 of the battery case 3. As shown in FIGS. 3 to 6, the hollow partition wall 32 has a shape in which the lower edge and both end edges of the hollow portion 33 are opened, and the outside air effectively flows through the hollow portion 33 and efficiently radiates heat. In the illustrated battery case 3, three battery blocks 10 are accommodated in parallel, and a hollow partition wall 32 is provided between the three battery blocks 10 so as to be thermally coupled to each battery block 10. In the illustrated battery pack, a plurality of battery blocks 10 are accommodated in a battery case 3 in a parallel posture, and a plate-shaped hollow partition wall 32 is provided between adjacent battery blocks 10.

  Further, the battery case 3 of FIG. 3 is connected to the bottom surface 31 of the battery case 3 and provided with a hollow partition wall 32. The hollow partition wall 32 is provided so as to extend upward from the bottom plate 31 of the battery case 3, and has a hollow portion 33 that opens downward. The hollow partition wall 32 approaches the battery block 10 disposed on both sides, is thermally coupled to the battery block 10, and dissipates the heat of the battery block 10 to the outside of the battery case 3. In particular, the hollow partition wall 32 having a hollow interior increases the heat radiation area in contact with the outside air and efficiently radiates the heat generated by the battery 1 to the outside. Moreover, the hollow partition wall 32 can also prevent induction of thermal runaway of the battery block 10 disposed on both sides of the hollow partition wall 32 due to the heat insulation of the hollow portion 33. This is because an abnormal temperature rise in one battery block 10 is blocked by the hollow portion 33 of the hollow partition wall 32.

  Furthermore, the battery pack shown in the figure includes a connection plate 40 that connects a plurality of battery blocks 10. As shown in FIGS. 3 and 7, the connecting plate 40 is disposed on the upper surface of the plurality of battery blocks 10, and is fixed to each battery block 10 via a set screw 16. Connected to a unitary structure. As shown in FIG. 7, the battery holder 2 of the battery block 10 is provided with connecting bosses 17 that are screwed into set screws 16 that pass through the connecting plate 40 so as to protrude from both ends of the upper surface. In the connection plate 40, a set screw 16 inserted into the through hole 44 is screwed into the connection boss 17 of the battery holder 2 to connect the plurality of battery blocks 10 in an integral structure. Furthermore, since the battery block 10 shown in the figure includes the circuit board 5 on the upper surface, the circuit board 5 can be disposed between the connection plate 40 and protected by the connection plate 40. This battery pack can be accommodated in the battery case 3 while connecting the plurality of battery blocks 10 with the connecting plate 40 in an integrated structure and protecting the circuit board 5 connected to each battery block 10 with the connecting plate 40. .

  The connecting plate 40 is manufactured by molding plastic. In the connection plate 40 of FIG. 16, a peripheral wall 42 that protrudes downward and upward is integrally formed along the outer periphery of a base plate 41 that is disposed to face the upper surfaces of the plurality of battery blocks 10. The peripheral wall 42 has an outer shape along the inner surface of the side wall 34 of the battery case 3 so as to be fitted to the opening edge of the battery case 3. The battery case 3 shown in FIG. 15 is formed by integrally forming a positioning rib 35 extending in the vertical direction on the inner surface of the side wall 34 and a connecting boss 36 that connects the lid case 30 that closes the opening of the battery case 3. Yes. The peripheral wall 42 of the connecting plate 40 shown in FIG. 16 has a slit 45 that guides the positioning rib 35 opened downward, and an outer peripheral recess 46 that guides the connecting boss 36 on the outer peripheral surface.

  Furthermore, the connection plate 40 protrudes from the lower surface of the base plate 41 and is integrally formed with a connection wall 43 that is connected to the hollow partition wall 32 of the battery case 3. Since the battery case 3 of FIG. 15 includes two rows of hollow partition walls 32 therein, the connection plate 40 is provided with two rows of connection walls 43 at positions facing these hollow partition walls 32. The connecting plate 40 is arranged at a fixed position of the battery case 3 by connecting the connecting wall 43 to the intermediate partition wall 32 with a fitting structure. The hollow partition wall 32 of the battery case 3 shown in FIG. 15 is provided with insertion protrusions 37 protruding from the upper surface along the hollow partition wall 32, and is connected to the insertion protrusions 37 to penetrate the connection plate 40. An intermediate connection boss 38 into which the set screw 15 is screwed is integrally formed. Further, as shown in FIG. 16, the connection wall 43 of the connection plate 40 is provided with an insertion groove 47 into which the insertion protrusion 37 of the hollow partition wall 32 is inserted along the lower end. Further, the connecting wall 43 is provided with a fitting recess 48 for cutting the connecting groove 47 at a position facing the intermediate connecting boss 38 of the hollow partition wall 32 and guiding the intermediate connecting boss 38 in a fitted state. A through hole 49 through which the set screw 15 is inserted is opened at the center of the fitting recess 48.

  The connecting plate 40 is inserted into the opening of the battery case 3 while guiding the connecting boss 36 of the battery case 3 to the outer peripheral recess 46 of the peripheral wall 42, and the positioning rib 35 of the battery case 3 is inserted into the slit 45 of the peripheral wall 42. Is inserted and placed at a fixed position of the opening edge of the battery case 3. Further, the connecting plate 40 fits the fitting protrusion 37 of the hollow partition wall 32 into the fitting groove 47 of the connecting wall 43 while guiding the intermediate connecting boss 38 of the hollow partition wall 32 to the fitting recess 48 of the connecting wall 43. Thus, the connecting wall 43 is connected to the hollow partition wall 32 with a fitting structure. Further, as shown in FIG. 7, the connection plate 40 has a set screw 15 that penetrates the through hole 49 at the center portion thereof screwed into the intermediate connection boss 38 of the hollow partition wall 32, and a through hole 50 at the end portion. A set screw 15 that penetrates is screwed into an end connecting boss 39 provided on the inner surface of the side wall 34, and is fixed to the battery case 3.

  Further, as shown in FIGS. 3, 5, and 7, the connection plate 40 fixes the main circuit board 60 on the upper surface. The main circuit board 60 is connected to the circuit board 5 provided in each battery block 10 via lead wires (not shown). The main circuit board 60 is mounted with a protection circuit (not shown) that controls charging / discharging of the battery 1 by a signal input from each circuit board 5. The main circuit board 60 is mounted with electronic components (not shown) that realize a switching element that controls the discharge current and a relay control circuit that controls the current of the battery 1 by a signal input from the circuit board 5. is doing. In the battery pack in which the plurality of circuit boards 5 are connected to the main circuit board 60 by lead wires (not shown), the voltage of any one of the batteries 1 is higher than the highest voltage or lower than the lowest voltage, Alternatively, when the temperature of the battery 1 is higher than the maximum temperature or lower than the minimum temperature, the switching element is turned off to interrupt the current of the battery 1. As described above, the battery pack that detects the voltage and temperature of each battery 1 and controls the current of the battery 1 can be used safely while protecting the battery 1.

  The plurality of battery blocks 10 are integrally connected via the connection plate 40 and stored in the battery case 3. The battery case 3 partitioned by the hollow partition wall 32 stores the battery block 10 in each partition. Further, the connecting plate 40 to which the plurality of battery blocks 10 are connected is fitted into the opening of the battery case 3 and fixed in place via the set screw 15.

  Further, the battery pack is filled with the potting resin 7 so as to embed the battery block 10 accommodated in the battery case 3, that is, so as to embed the battery 1. The potting resin 7 is filled with an uncured paste with urethane resin, epoxy resin, silicon resin or the like, and embeds the battery 1 and the battery holder 2. The battery pack in which the battery case 3 in which the battery block 10 is put is filled with the potting resin 7 is in close contact with the inner surface of the battery case 3 without gaps, and the potting resin 7 and the battery case 3 are ideally coupled to each other. It can be in the state. However, for a battery pack in which the battery is embedded in the potting resin, the battery block is placed in a molding container, filled with the potting resin, and after the potting resin is cured, it is removed from the molding container and stored in the battery case. You can also. In this structure, the inner shape of the molded container is the inner shape of the battery case, and the potting resin can be in close contact with the inner surface of the battery case. Since this battery pack can take out the battery block embedded in potting resin from a battery case, it has the characteristics which can perform maintenance, such as replacement | exchange of a battery block.

The above battery pack is assembled as follows.
(1) As shown in FIG. 12, the heat radiating plate 8 is inserted into the insertion portion 21 and the slit 20 of the holder unit 2A divided into two parts, and all the cylindrical batteries 1A are inserted into the insertion portion 21 to form a cylindrical shape. A battery holder 2 is formed by connecting a pair of holder units so that the battery 1A is fitted in the U-groove 8A of the heat dissipation plate. The holder unit 2 </ b> A is connected by providing the inflow gap 24 on the opposite surface by the gap connector 23. Furthermore, as shown in FIG. 10, the lead plate 4 is welded and fixed to the end face electrode of each battery 1.
(2) The circuit board 5 is fixed to the upper surface of the battery holder 2 as shown in FIG. The circuit board 5 is fixed to the battery holder 2 through a set screw 18 penetrating the circuit board 5.
(3) The connecting portion 4A of the lead plate 4 is connected to the circuit board 5 via the lead wire 6.
The battery block 10 is assembled through the above steps.

(4) As shown in FIG. 7, the plurality of battery blocks 10 are connected to the connection plate 40. The plurality of battery blocks 10 are connected to the connection boss 17 of each battery holder 2 by screwing a set screw 16 penetrating the connection plate 40 into an integral structure.
(5) A plurality of battery blocks 10 connected by the connection plate 40 are stored in the battery case 3. Each battery block 10 is accommodated in each compartment partitioned by the hollow partition wall 32. The connection plate 40 is arranged at a fixed position of the battery case 3 with a fitting structure, and is fixed to a fixed position of the battery case 3 via a set screw 15.
In the above steps, the battery blocks 10 are stored in the battery case 3 after the plurality of battery blocks 10 are connected to the integrated structure by the connection plate 40. However, after the battery blocks are stored in the battery case, the connection plate Can be inserted into the battery case, and the connecting plate can be connected to each battery block.
(6) As shown in FIG. 3, the battery case 3 is filled with a paste-like uncured potting resin 7.
(7) After the potting resin 7 is cured, the lid case 30 is connected to the opening of the battery case 3 and closed. The lid case 30 is fixed by screwing a set screw 14 penetrating the outer peripheral portion into a connecting boss 36 provided in the opening of the battery case 3.

DESCRIPTION OF SYMBOLS 1 ... Battery 1A ... Cylindrical battery 2 ... Battery holder 2A ... Holder unit 3 ... Battery case 4 ... Lead plate 4A ... Connection part 5 ... Circuit board 6 ... Lead wire 7 ... Potting resin 8 ... Radiation plate 8A ... U groove
8B ... Connection part 10 ... Battery block 14 ... Set screw 15 ... Set screw 16 ... Set screw 17 ... Connection boss 18 ... Set screw 19 ... Set screw 20 ... Slit 21 ... Insertion part 21A ... Insertion recess 22 ... Partition wall 22a ... Thin wall part
22b ... Thin portion 23 ... Gap connector 23X ... Connection boss
23a ... Connection convex part
23b: Connecting cylinder part 24: Inflow gap 25 ... Filling groove 26 ... Positioning recess 27 ... Holder part 28 ... Positioning rib 28A ... Notch part 29 ... Connecting boss 30 ... Lid case 31 ... Bottom surface 32 ... Hollow partition wall 33 ... Hollow Numeral 34 ... Side wall 35 ... Positioning rib 36 ... Connection boss 37 ... Insertion protrusion 38 ... Intermediate connection boss 39 ... End connection boss 40 ... Connection plate 41 ... Base plate 42 ... Peripheral wall 43 ... Connection wall 44 ... Through hole 45 ... Slit 46 ... Outer peripheral recess 47 ... Fitting groove 48 ... Fitting recess 49 ... Through hole 50 ... Through hole 60 ... Main circuit board 91 ... Cylindrical battery 92 ... Battery holder 98 ... Heat dissipation plate

Claims (4)

A plurality of cylindrical batteries (1A) that can be charged are set in the insertion part (21) of the battery holder (2), and are battery packs having battery blocks (10) arranged in multiple stages and multiple rows,
The battery holder (2) is connected to a heat radiating plate (8) that is thermally coupled to the surface of the cylindrical battery (1A), and the heat radiating plate (8) fits the cylindrical battery (1A). A metal plate is formed in a corrugated shape in which U-grooves (8A) to be worn are alternately provided on the opposite surface. The battery pack is characterized in that the cylindrical battery (1A) is alternately inserted and the outer peripheral surface of the cylindrical battery (1A) is thermally coupled to the inner surface of the U groove (8A).   A plurality of heat dissipation plates (8) are connected to the battery holder (2), and a cylindrical battery (1A) housed in a multistage multi-row in the battery holder (2) is connected in series with a lead plate (4). The heat exchanger plate according to claim 1, wherein the cylindrical batteries (1 </ b> A) connected in parallel with each other and the heat radiating plates (8) connected in parallel with each other are arranged in the U groove (8 </ b> A) and thermally coupled. Battery pack.   The battery holder (2) is formed of an insulating material, and has a slit (20) for disposing the heat radiating plate (8) at a fixed position, and the heat radiating plate (8) is inserted into the slit (20). The battery pack according to claim 2, wherein the battery pack is disposed at a fixed position. The battery holder (2) is composed of a pair of holder units (2A) divided into two parts, and each cylindrical battery (1A) has an insertion part (21A) of a separate holder unit (2A) with its ends separated. ) And placed in place,
Each holder unit (2A) has a slit (20) that opens to the opposite surface, and the heat dissipation plate (8) is inserted into the slit (20), and the heat dissipation plate (8) is inserted into the battery holder (2). The battery pack according to claim 3, wherein the battery packs are connected.

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