JP4956773B2 - Battery pack and battery pack case - Google Patents

Description

  The present invention relates to a battery pack and a battery pack case.

  A battery pack having a high output and a high capacity is obtained by electrically connecting a plurality of single cells in series and / or in parallel (see Patent Document 1). In general, a battery pack includes a battery module as a unit unit for assembly. This battery module is configured by storing a cell unit holding a single battery in a case and leading out positive and negative output terminals from the case. A battery pack is manufactured by electrically connecting a number of battery modules corresponding to the required output and capacity in series and / or in parallel. The battery modules are fastened to each other by inserting through bolts.

As the unit cell, a flat type battery in which a power generation element is sealed with an exterior material such as a laminate film is widely used. In a flat battery, positive and negative electrode terminals having a plate shape are led out from an exterior material. In order to maintain the battery performance of the unit cell, it is necessary to keep the distance between the electrode plates in the power generation element uniform. For this reason, the power generation element of a battery is pressed down using the case body which wraps a cell unit.
JP 2001-229896 A

  Since the battery modules are fastened to each other, for example, even if it is necessary to replace only some of the cell units, the cell units must be replaced unless all the battery modules are fastened. I can't.

  In addition, since the battery modules are fastened to each other to form the battery pack, there is a problem that the positioning of the battery modules is difficult and the assembly of the battery pack becomes complicated.

  An object of the present invention is to provide a battery pack and a battery pack case capable of facilitating cell unit replacement work and simplifying assembly.

The invention according to claim 1 for achieving the above object includes a cell unit holding a battery,
A storage container provided with a storage chamber in which the cell unit is removably stored;
Wherein provided in the housing chamber, it possesses a press section to impart the surface pressure of the battery thickness direction with respect to the battery of the cell units inserted, and,
The said press part is a battery pack which has the conversion member comprised from the cam which converts the force at the time of inserting the said cell unit in the said storage chamber into the surface pressure of the said battery thickness direction .

Further, the invention according to claim 6 for achieving the above object includes a storage container provided with a storage chamber in which a cell unit holding a battery is detachably stored;
A press portion that is provided in the storage chamber and applies a surface pressure in the battery thickness direction to the battery of the cell unit inserted , and
The said press part is a case for battery packs which has the conversion member comprised from the cam which converts the force at the time of inserting the said cell unit in the said storage chamber into the surface pressure of the said battery thickness direction .

  The battery pack of the present invention and the battery pack using the battery pack case of the present invention are configured by inserting the cell unit into the storage chamber of the storage container, and the cell units are not directly fastened. For this reason, for example, when it is necessary to replace only the cell unit, it is sufficient to extract only the cell unit and insert a new cell unit, thereby facilitating the replacement operation of the cell unit. .

  A press section provided in the storage chamber applies a surface pressure in the battery thickness direction to the battery of the inserted cell unit. For this reason, by simply inserting the cell unit into the storage chamber, the distance between the electrode plates can be kept uniform, the battery performance can be maintained, and the assembly of the battery pack can be simplified.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 is a perspective view showing the battery pack 11 according to the first embodiment, FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1, and FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. 2, and FIG. 5 is a cross-sectional view showing a state in the middle of inserting the cell unit 30 into the storage chamber 41 of the storage container 40 in the first embodiment. 6 is a perspective view showing an example of the battery 20, and FIG. 7 is a perspective view showing the upper restraining plate 32 of the cell unit 30. The surface on the right front side shown in FIG. 1 is referred to as the front surface of the battery pack 11 or the storage container 40, and the surface on the back left side is referred to as the back surface.

  As shown in the drawing, the battery pack 11 of the first embodiment can be summarized as a cell unit 30 holding a flat battery 20 (corresponding to a battery), and a storage in which the cell unit 30 is detachably inserted. A storage container 40 provided with a chamber 41, and a press unit 50 provided in the storage chamber 41 to apply a surface pressure in the battery thickness direction to the flat battery 20 of the inserted cell unit 30. ing. The storage container 40 and the press unit 50 constitute a battery pack case according to the present invention. The illustrated storage container 40 is provided with a plurality of storage chambers 41, and a press portion 50 is provided in each of the storage chambers 41. The battery pack 11 is mounted and used in a vehicle such as an automobile or a train. This will be described in detail below. The flat battery 20 is simply referred to as “battery 20”.

  Referring to FIG. 6, the battery 20 is, for example, a flat lithium ion secondary battery, and a laminated power generation element (not shown) in which a positive electrode plate, a negative electrode plate, and a separator are sequentially laminated is a laminate film or the like. It is sealed with an exterior material 20a. One end of the battery 20 is electrically connected to the power generation element, and a tab-like tab 20t is led out from the exterior member 20a. The tabs 20t extend on both sides of the battery 20 in the longitudinal direction. The tab 20t is a general term for the plus side tab 20p and the minus side tab 20m.

  2 to 4, the cell unit 30 includes a holding plate 31 that holds the tab 20 t and upper and lower restraining plates 32 and 33 that hold the battery 20 and the holding plate 31. In the illustrated cell unit 30, a plurality (eight) of batteries 20 are stacked in the battery thickness direction (vertical direction in FIG. 3). The stacked eight batteries 20 are connected in series, with the plus tab 20p of the upper battery 20 and the minus tab 20m of the lower battery 20 connected.

  Each holding plate 31 has a size that covers the tab 20t. The length of the holding plate 31 along the longitudinal direction is substantially equal to the length of the battery 20 in the short direction, that is, the width. The holding plate 31 is made of an electrically insulating material, for example, an electrically insulating resin material. Each of the tabs 20t is sandwiched between holding plates 31 from both sides along the battery stacking direction. Note that the tab 20 t is sandwiched between the holding plate 31 and the end plate 34 of the lower restraint plate 33 with respect to the battery 20 at the lowermost stage.

  As shown in FIG. 7, the upper restraint plate 32 includes a pair of end plates 34 positioned at both ends along the longitudinal direction, a center plate 35 positioned substantially at the center of the pair of end plates 34, the end plate 34 and the center. And a connection plate 36 for connecting the plate 35. The end plate 34 and the center plate 35 extend along the width direction of the battery 20, and the connection plate 36 extends along the longitudinal direction of the battery 20. The lengths of the restraining plates 32 and 33 along the longitudinal direction are substantially equal to the length of the battery 20 in the longitudinal direction, and the end plate 34 overlaps the holding plate 31. Bolt holes 37 are formed in the end plates 34 of the restraining plates 32 and 33. Bolt holes (not shown) are similarly formed in the holding plate 31. The restraint plates 32 and 33 are also formed from the same resin material as the holding plate 31. The battery 20 and the holding plate 31 are sandwiched between restraining plates 32 and 33 from both sides along the battery stacking direction. The bolts inserted through the bolt holes 37 are fastened by nuts (none of which are shown), and the holding plate 31 and the end plates 34 of the restraining plates 32 and 33 are fixed to each other. In this way, the cell unit 30 holds the battery 20.

  As shown in FIGS. 2, 4, and 5, positive and negative output terminals 38 and 39 are provided on the back surface of the cell unit 30. For example, the plus side output terminal 38 is connected to the minus side tab 20 m of the lowest battery 20, and the minus side output terminal 39 is connected to the plus side tab 20 p of the highest battery 20. The positive and negative output terminals 38 and 39 have a bolt shape.

  The storage container 40 has a shelf shape in which a plurality of storage chambers 41 are provided. As shown in FIG. 1, the storage container 40 is provided with a total of 12 storage chambers 41 in three rows in the vertical direction and in four rows in the horizontal direction. A step may be provided in accordance with the space shape in which the storage container 40 is installed (for example, the left two rows are two steps, the right two rows are four steps). One cell unit 30 is detachably stored in one storage chamber 41. Each storage chamber 41 is partitioned by an upper surface wall 42a, a pair of left and right side walls 42b, and a rear wall 42c, and an insertion port 43 for inserting and removing the cell unit 30 is opened on the front surface. The storage container 40 is formed from a steel plate or an aluminum plate.

  The storage container 40 has a container-side terminal 44 that is electrically connected to the positive and negative output terminals 38 and 39 of the cell unit 30 inserted into the storage chamber 41. The container side terminal 44 is comprised from suitable connection members, such as a bus bar. The bus bar 44 forming the container side terminal is attached to the inner surface of the back wall 42c, and a through hole through which the positive and negative output terminals 38 and 39 are inserted is formed. The output terminals 38 and 39 inserted through the through holes are fastened by nuts 45, and the output terminals 38 and 39 and the bus bar 44 are electrically connected. The cell units 30 are connected in series and / or in parallel using a bus bar 44. By connecting a plurality of cell units 30 in series and parallel, the battery pack 11 corresponding to a desired current, voltage, and capacity can be formed.

  As shown in FIG. 3, the battery pack 11 is provided with a slide mechanism 60 that guides insertion / removal of the cell unit 30. The slide mechanism 60 includes upper and lower guide rails 61 and 62 provided in the storage container 40 and upper and lower guide grooves 63 and 64 provided in the cell unit 30 and fitted into the guide rails 61 and 62. . Each of the upper and lower guide rails 61 and 62 protrudes from the inner surface of the side wall 42b toward the storage chamber 41, and extends from the insertion port 43 toward the back wall 42c. The upper guide rail 61 is provided with an upper engaging portion that is bent downward, and the lower guide rail 62 is provided with a lower engaging portion that is bent upward. Each of the upper and lower guide grooves 63 and 64 extends along the longitudinal direction of the upper and lower restraint plates 32 and 33. The upper guide groove 63 is formed on the upper surfaces of the end plate 34 and the center plate 35 of the upper restraint plate 32, and the lower guide groove 64 is formed on the lower surfaces of the end plate 34 and the center plate 35 of the lower restraint plate 33. A stopper (not shown) is provided on the guide rails 61 and 62, and the insertion position of the cell unit 30 is determined by a part of the cell unit 30 coming into contact with the stopper.

  In order to maintain the battery performance by keeping the distance between the electrode plates uniform, the battery 20 needs to be pressed by applying pressure to the power generation element. Therefore, in the first embodiment, the storage chamber 41 is provided with a press unit 50 that applies a surface pressure in the battery thickness direction to the battery 20.

  The press unit 50 includes a conversion member that converts a force when the cell unit 30 is inserted into the storage chamber 41 into a surface pressure in the battery thickness direction. The conversion member is composed of a cam 51. In the first embodiment, the press unit 50 further includes a leaf spring 52.

  More specifically, referring to FIGS. 4 and 5, the leaf spring 52 has a substantially rectangular shape that can be elastically deformed. Three leaf springs 52 are attached to the inner surface of the upper surface wall 42a. The three leaf springs 52 are arranged so as to be positioned above the connection plate 36 of the upper restraint plate 32 along the direction in which the cell unit 30 is inserted and removed. The base end portion of the upper end of the leaf spring 52 in the figure has a key shape that engages with a key groove formed on the inner surface of the upper surface wall 42a. The leaf spring 52 is locked by fitting its base end portion into the key groove and rotating it 90 degrees. As shown in FIG. 7, a cam 51 serving as a conversion member is provided on the upper surface of the connection plate 36 of the upper restraining plate 32. The cam 51 protrudes from the upper surface of the connection plate 36 toward the inner surface of the upper surface wall 42a. The front surface and the back surface along the direction in which the cell unit 30 is inserted and removed from the end surface of the cam 51 are formed on an inclined cam surface 51a. The leaf spring 52 is elastically compressed when it comes into contact with the upper surface 51 b of the cam 51, and gives elastic force to the cell unit 30 by elastic deformation.

  Next, the operation will be described.

  When assembling the battery pack 11, first, the leaf spring 52 is attached to the inner surface of the upper surface wall 42 a of each storage chamber 41. The cell unit 30 holding the battery 20 is inserted into the storage chamber 41 from the insertion port 43. At this time, the upper guide groove 63 of the cell unit 30 is fitted into the upper guide rail 61, and the lower guide groove 64 is fitted into the lower guide rail 62. The cell unit 30 is slid while being guided by the upper and lower guide rails 61 and 62 and the upper and lower guide grooves 63 and 64.

  When each leaf spring 52 is not in contact with the cam 51, it is in an initial state where it is not elastically deformed (see FIG. 5). When the cell unit 30 is inserted from this state, each leaf spring 52 rides on the cam 51 while abutting on the cam surface 51a and being elastically compressed. When the cell unit 30 is inserted to a predetermined insertion position, each leaf spring 52 abuts on the upper surface 51b of the cam 51 and is elastically compressed, and the elastic force caused by elastic deformation via the upper surface 51b of the cam 51. Is given to the cell unit 30. Thus, the force when the cell unit 30 is inserted into the storage chamber 41 is converted into the surface pressure in the battery thickness direction by the cam 51. Furthermore, the elastic force by the elastic deformation of each leaf spring 52 is applied to the cell unit 30. Thus, the press part 50 gives the surface pressure of a battery thickness direction with respect to the battery 20 of the inserted cell unit 30. FIG. As a result, in the battery 20, the distance between the electrode plates is kept uniform, and the battery performance is maintained.

  The positive and negative output terminals 38 and 39 of the cell unit 30 are inserted through the through holes of the bus bar 44 and protrude outward from the back wall 42c. Then, the nut 45 is fastened to the output terminals 38 and 39, and the output terminals 38 and 39 and the bus bar 44 are electrically connected. A plurality of cell units 30 are connected in series and parallel via the bus bar 44, and the assembly of the battery pack 11 corresponding to the desired current, voltage, and capacity is completed.

  The battery pack 11 is air-cooled, and the plurality of cell units 30 are stored with a space therebetween. The space is used as a cooling air passage through which cooling air for cooling each of the cell units 30 flows. By cooling each cell unit 30 by flowing cooling air, it is possible to reduce battery temperature and suppress deterioration of characteristics such as charging efficiency. Since the space is formed simply by inserting the cell unit 30 into the storage chamber 41, there is no need to arrange a collar for forming a gap between the cell units 30.

  The battery pack 11 of 1st Embodiment is comprised by inserting the cell unit 30 in the storage chamber 41 of the storage container 40, and the cell units 30 are not fastened directly. For this reason, for example, when it is necessary to replace only some of the cell units 30, it is sufficient to extract only the cell unit 30 and insert a new cell unit 30. Simplification can be achieved.

  The press part 50 provided in each of the storage chambers 41 applies a surface pressure in the battery thickness direction to the battery 20 of the inserted cell unit 30. For this reason, the distance between the electrode plates can be kept uniform, and the battery performance can be maintained.

  When assembling the battery pack 11, there is no need to insert a bolt through the storage container 40 or arrange a collar between the cell units 30, and the number of mounting steps and the number of parts can be reduced. From this point of view, the assembly of the battery pack 11 can be simplified.

  Since the surface pressure in the battery thickness direction is generated by the press unit 50, the surface pressure can be easily adjusted and managed as compared with the case where the power generation element of the battery 20 is pressed using a case body that wraps the cell unit 30. Can do. The operation of wrapping the cell unit with the case body so as to obtain a predetermined surface pressure and the case body itself can be abolished. From this viewpoint, the assembly of the battery pack 11 can be simplified.

  Since the cell unit 30 has a plurality of batteries 20 stacked in the battery thickness direction, the cell unit 30 corresponding to a desired current, voltage, and capacity can be manufactured.

  Since the storage container 40 is provided with a plurality of storage chambers 41 and has a shelf shape, a necessary number of cell units 30 can be easily stored. Furthermore, the relative positioning of the cell units 30 can be performed only by inserting the cell units 30 into the storage chamber 41 of the storage container 40. For this reason, relative positioning of the cell units 30 is easier and the assembly of the battery pack 11 is simpler than in a configuration in which the battery modules in which the cell units are housed in the case are fastened together. Can be achieved.

  Since the storage container 40 has the container side terminal 44 that is electrically connected to the output terminals 38 and 39 of the inserted cell unit 30, the electrical connection work between the cell unit 30 and the container side terminal 44 is performed. Can be performed simultaneously with the operation of inserting the cell unit 30.

  Since the pressing unit 50 includes a conversion member that converts a force when the cell unit 30 is inserted into the storage chamber 41 into a surface pressure in the battery thickness direction, the operation of applying the surface pressure to the battery 20 is performed. Can be performed at the same time as inserting.

  By configuring the conversion member from the cam 51, the force when the cell unit 30 is inserted into the storage chamber 41 can be easily converted into the surface pressure in the battery thickness direction.

  Since the press unit 50 further includes a leaf spring 52, the elastic force due to the elastic deformation of the leaf spring 52 is applied to the cell unit 30, and the surface pressure in the battery thickness direction is reliably applied to the battery 20. Can do.

(Second Embodiment)
FIG. 8 is a cross-sectional view showing the battery pack 12 according to the second embodiment, and FIG. 9 is a cross-sectional view showing a state in the middle of inserting the cell unit 70 into the storage chamber 41 of the storage container 40 in the second embodiment. FIG. 10 is a perspective view showing the restraining plate 71 of the cell unit 70. In addition, the same code | symbol is attached | subjected to the member which is common in 1st Embodiment, and the description is abbreviate | omitted in part.

  The cell unit 70 includes a holding plate 31 that holds the tab 20 t and upper and lower restraining plates 71 that hold the battery 20 and the holding plate 31. As shown in FIG. 10, the constraining plate 71 of the second embodiment has a rectangular shape as a whole, and is provided with a side connection plate 72 in addition to the central connection plate 36.

  As shown in FIGS. 8 and 9, the battery pack 12 is provided with a slide mechanism 80 that guides insertion / removal of the cell unit 70. The slide mechanism 80 includes upper and lower guide grooves 81 and 82 provided in the storage container 40 and upper and lower guide pins 83 and 84 provided in the cell unit 70 and fitted into the guide grooves 81 and 82. . Each of the upper and lower guide grooves 81 and 82 is formed on the inner surface of the side wall 42b and extends from the insertion port 43 toward the back wall 42c. Each of the upper and lower guide pins 83 and 84 is provided so as to protrude in the lateral direction, that is, the width direction of the upper and lower restraint plates 71. Three guide pins 83, 84 are provided on the side connection plate 72.

  The press part 90 of 2nd Embodiment has the conversion member which converts the force at the time of inserting the cell unit 70 in the storage chamber 41 into the surface pressure of a battery thickness direction similarly to 1st Embodiment. . The conversion member is composed of a cam 91. However, unlike the first embodiment, the press part 90 does not have a leaf spring.

  More specifically, a cam 91 serving as a conversion member is provided on the inner surface of the side wall 42b. The cam 91 has a cam groove 91 a that is continuous with the upper guide groove 81. The cam groove 91a is inclined downward from the upper guide groove 81 toward the back wall 42c. The cam groove 91 a is continuous with the lateral groove 92 extending toward the back wall 42 c in parallel with the upper guide groove 81. The lower guide groove 82 extends in parallel with the upper guide groove 81. The insertion position of the cell unit 70 is determined by the guide pins 83 and 84 coming into contact with the end portions of the lateral groove 92 and the lower guide groove 82. When the upper guide pin 83 reaches the lateral groove 92 from the upper guide groove 81 through the cam groove 91a, the upper restraint plate 71 moves toward the lower restraint plate 71. A pressing force is applied to the cell unit 70 by reducing the dimension between the upper and lower restraint plates 71.

  Next, the operation will be described.

  When assembling the battery pack 12, the cell unit 70 holding the battery 20 is inserted into the storage chamber 41 from the insertion port 43. At this time, the upper guide pin 83 of the cell unit 70 is fitted into the upper guide groove 81 and the lower guide pin 84 is fitted into the lower guide groove 82. The cell unit 70 is slid while being guided by the upper and lower guide grooves 81 and 82 and the upper and lower guide pins 83 and 84.

  While the upper guide pin 83 slides in the upper guide groove 81, the upper restraint plate 71 is in an initial state in which it does not move toward the lower restraint plate 71 (see FIG. 9). When the cell unit 70 is inserted from this state and the upper guide pin 83 reaches the lateral groove 92 from the upper guide groove 81 via the cam groove 91a, the upper restraint plate 71 moves toward the lower restraint plate 71. A pressing force is applied to the cell unit 70 by reducing the dimension between the upper and lower restraint plates 71. Thus, the force when the cell unit 70 is inserted into the storage chamber 41 is converted into the surface pressure in the battery thickness direction by the cam 91. Thus, the press part 90 gives the surface pressure of the battery thickness direction with respect to the battery 20 of the inserted cell unit 70. As a result, in the battery 20, the distance between the electrode plates is kept uniform, and the battery performance is maintained.

  As in the first embodiment, the battery pack 12 of the second embodiment is configured by inserting the cell unit 70 into the storage chamber 41 of the storage container 40, thereby facilitating replacement work of the cell unit 70. Can be planned. Further, the cell unit 70 can be positioned simply by inserting the cell unit 70 into the storage chamber 41 of the storage container 40, and the assembly of the battery pack 12 can be simplified.

  The press part 90 provided in each of the storage chambers 41 applies a surface pressure in the battery thickness direction to the battery 20 of the inserted cell unit 70. For this reason, the distance between the electrode plates can be kept uniform, and the battery performance can be maintained.

  Since the press unit 90 includes a conversion member that converts a force when the cell unit 70 is inserted into the storage chamber 41 into a surface pressure in the battery thickness direction, the operation of applying the surface pressure to the battery 20 is performed. Can be performed at the same time as inserting.

  By configuring the conversion member from the cam 91, the force when the cell unit 70 is inserted into the storage chamber 41 can be easily converted into the surface pressure in the battery thickness direction.

(Other variations)
In the present invention, the number of cell units 30 and 70 stored in one storage chamber 41 is not limited. For example, a plurality of cell units 30 and 70 may be stored in one storage chamber 41. Further, an uneven fitting portion may be provided on the outer surface of the storage container 40 so that a plurality of storage containers 40 can be stacked and connected in the vertical direction, or can be connected side by side in the horizontal direction.

  In the cell units 30 and 70 described above, a plurality of batteries 20 are electrically connected, but the present invention is also applicable to a cell unit including only one battery 20.

It is a perspective view which shows the battery pack which concerns on 1st Embodiment. It is sectional drawing which follows the 2-2 line of FIG. It is sectional drawing which follows the 3-3 line of FIG. FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. It is sectional drawing which shows the state in the middle of inserting the cell unit in the storage chamber of a storage container in 1st Embodiment. It is a perspective view which shows an example of a battery. It is a perspective view which shows the upper restraint board of a cell unit. It is sectional drawing which shows the battery pack which concerns on 2nd Embodiment. It is sectional drawing which shows the state in the middle of inserting the cell unit in the storage chamber of a storage container in 2nd Embodiment. It is a perspective view which shows the restraint board of a cell unit.

Explanation of symbols

11, 12 battery pack,
20 batteries,
30 cell units,
31 holding plate,
32, 33 Upper and lower restraint plates,
38, 39 output terminals,
40 storage container,
41 storage room,
43 insertion slot,
44 Bus bar (container side terminal),
45 nuts,
50 Press department,
51 cam (conversion member),
51a cam surface,
51b The upper surface of the cam,
52 leaf spring,
60 slide mechanism,
61, 62 Upper and lower guide rails,
63, 64 upper and lower guide grooves,
70 cell units,
71 Upper and lower restraint plates,
80 slide mechanism,
81, 82 Upper and lower guide grooves,
83, 84 Upper and lower guide pins,
90 Press part,
91 cam (conversion member),
91a cam groove,
92 Transverse groove.

Claims (6)

A cell unit holding a battery;
A storage container provided with a storage chamber in which the cell unit is removably stored;
Wherein provided in the housing chamber, it possesses a press section to impart the surface pressure of the battery thickness direction with respect to the battery of the cell units inserted, and,
The said press part is a battery pack which has the conversion member comprised from the cam which converts the force at the time of inserting the said cell unit in the said storage chamber into the surface pressure of the said battery thickness direction .   The battery pack according to claim 1, wherein the cell unit includes a plurality of the batteries stacked in the battery thickness direction.   The battery pack according to claim 1, wherein the storage container has a shelf shape.   The battery pack according to claim 1, wherein the storage container has a container-side terminal that is electrically connected to an output terminal of the inserted cell unit. The battery pack according to claim 1, wherein the press portion further includes a leaf spring .   A storage container provided with a storage chamber in which a cell unit holding a battery is removably stored;
  A press portion that is provided in the storage chamber and applies a surface pressure in the battery thickness direction to the battery of the cell unit inserted, and
  The said press part is a case for battery packs which has the conversion member comprised from the cam which converts the force at the time of inserting the said cell unit in the said storage chamber into the surface pressure of the said battery thickness direction.

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