JP2022078378A - Power supply device, electric vehicle using the same and power storage device - Google Patents

Abstract

To provide a power supply device having improved followability to deformation such as expansion and contraction of a secondary battery cell, an electric vehicle using the same, and a power storage device.SOLUTION: A power supply device 100 includes a plurality of secondary battery cells 1 each having a square outer packaging can, a pair of end plates 20 covering both end faces of a battery laminate 10 in which the plurality of secondary battery cells 1 are laminated, and a plurality of fastening members 15 which are formed in a plate-like shape to extend along a lamination direction of the plurality of secondary battery cells 1, and arranged on the opposite side surfaces of the battery laminate 10 to fasten the end plates 20 to each other. Further, a space SP is formed at an intermediate portion in the lamination direction of the battery laminate 10. In the space SP is provided a spring member 40 which is urged to press the battery laminate 10 in the lamination direction.SELECTED DRAWING: Figure 2

Description

The present invention relates to a power supply device, an electric vehicle using the power supply device, and a power storage device.

The power supply device is used as a power supply device for driving an electric vehicle, a power supply device for storing electricity, and the like. In such a power supply device, a plurality of rechargeable secondary battery cells are stacked. Generally, as shown in the perspective view of FIG. 20, the power supply device 900 has a secondary battery cell 901 of a square outer can on both end faces of a battery laminate in which insulating spacers 902 are alternately laminated. , Each end plate 903 is arranged, and the end plates 903 are fastened to each other with a metal bind bar 904.

The outer can of the secondary battery cell expands and contracts when charging and discharging are repeated. In particular, with the recent demand for higher capacity, the capacity of each secondary battery cell is increasing, and as a result, the amount of expansion tends to increase. In a battery laminate in which a large number of such secondary battery cells are laminated and fastened, the amount of expansion also increases according to the number of secondary battery cells. As a result, the load on the bind bar increases. On the other hand, it is conceivable to increase the strength of the bind bar.

However, even if the bind bar is made of a high-strength metal plate, the restoring force is weak because the elastic modulus is low in the case of metal. That is, when the secondary battery cell expands, even if the metal bind bar is stretched and deformed, when the secondary battery cell contracts, the bind bar does not return to its original shape. There is a problem that the fastening force of the battery laminate by the bar is reduced and the position is displaced due to impact or vibration.

Japanese Unexamined Patent Publication No. 9-120808

One of an object of the present invention is to provide a power supply device having improved followability to deformation such as expansion and contraction of a secondary battery cell, an electric vehicle using the power supply device, and a power storage device.

The power supply device according to a certain aspect of the present invention includes a plurality of secondary battery cells having a square outer can, a pair of end plates covering both end faces of a battery laminate in which the plurality of secondary battery cells are laminated, and a pair of end plates. It has a plate shape extended along the stacking direction of the plurality of secondary battery cells, and is provided with a plurality of fastening members arranged on opposite side surfaces of the battery laminate to fasten the end plates to each other. .. Further, a space is formed in the intermediate portion of the battery laminate in the stacking direction. The space is provided with a spring member urged to press the stacking direction of the battery laminate.

According to the above power supply device, it is possible to maintain the fastened state by the spring member while absorbing the deformation of the length of the battery laminate in the stacking direction by the space provided in the stacking direction of the secondary battery cells.

It is a perspective view which shows the power supply device which concerns on Embodiment 1. FIG. It is an exploded perspective view of the power supply device of FIG. It is a top view of the power supply device of FIG. FIG. 3 is a horizontal sectional view taken along line IV-IV of the power supply device of FIG. FIG. 3 is a vertical cross-sectional view taken along the line VV of the power supply device of FIG. It is an exploded perspective view of the fastening member of FIG. It is a perspective view of a spring member. It is a horizontal sectional view of the power supply device which concerns on Embodiment 2. FIG. It is a perspective view which shows the state which the spring member was contracted. It is a perspective view which shows the state which the spring member was stretched. 3 is a perspective view showing a spring member of the power supply device according to the third embodiment. It is a perspective view which shows the spring member of the power supply device which concerns on Embodiment 4. FIG. It is a perspective view which shows the spring member of the power supply device which concerns on Embodiment 5. It is a perspective view which shows the spring member of the power supply device which concerns on Embodiment 6. It is a perspective view of the power supply device which concerns on Embodiment 7. It is an exploded perspective view of the power supply device which concerns on a comparative example. It is a block diagram which shows an example which mounts a power supply device in a hybrid vehicle which runs by an engine and a motor. It is a block diagram which shows the example which mounts the power-source device on the electric vehicle which runs only by a motor. It is a block diagram which shows the example which applies to the power-source device for electricity storage. It is an exploded perspective view which shows the conventional power supply device.

Embodiments of the present invention may be specified by the following configurations.

The power supply device according to an embodiment of the present invention further includes pressing plates for fixing the spring member on both sides of the spring member.

In the power supply device according to another embodiment of the present invention, the pressing plate is a resin member in which the spring member is insert-molded.

Further, in the power supply device according to another embodiment of the present invention, the spring member is fixed to the center of the pressing plate.

Further, in the power supply device according to another embodiment of the present invention, the space is arranged at the center in the stacking direction of the battery laminate.

Furthermore, in the power supply device according to another embodiment of the present invention, the spring member is a coil spring.

Furthermore, in the power supply device according to another embodiment of the present invention, the spring member is a leaf spring.

Furthermore, the power supply device according to another embodiment of the present invention is provided with a plurality of the spring members.

Furthermore, the electric vehicle according to another embodiment of the present invention is a vehicle equipped with any of the above power supply devices, a traveling motor supplied with electric power from the power supply device, the power supply device, and the motor. It includes a main body and wheels driven by the motor to drive the vehicle main body.

Furthermore, the power storage device according to another embodiment of the present invention includes any of the above power supply devices and a power supply controller that controls charging / discharging to the power supply device, and the power supply controller is used to generate electric power from the outside. Allows the secondary battery cell to be charged and is controlled to charge the secondary battery cell.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiments shown below are examples for embodying the technical idea of the present invention, and the present invention is not specified as the following. Further, the present specification does not specify the members shown in the claims as the members of the embodiment. In particular, the dimensions, materials, shapes, relative arrangements, and the like of the constituent members described in the embodiments are not intended to limit the scope of the present invention to the specific description, and are merely explanatory examples. It's just that. The size and positional relationship of the members shown in each drawing may be exaggerated for the sake of clarity. Further, in the following description, members of the same or the same quality are shown with the same name and reference numeral, and detailed description thereof will be omitted as appropriate. Further, each element constituting the present invention may be configured such that a plurality of elements are composed of the same member and the plurality of elements are combined with one member, or conversely, the function of one member is performed by the plurality of members. It can also be shared and realized. In addition, the contents described in some examples and embodiments can be used in other embodiments and embodiments.

The power supply device according to the embodiment is a power source mounted on an electric vehicle such as a hybrid vehicle or an electric vehicle to supply electric power to a traveling motor, a power source for storing electric power generated by natural energy such as solar power generation or wind power generation, or a power source for storing electric power generated by natural energy such as solar power generation and wind power generation. It is used for various purposes such as a power source for storing midnight power, and is particularly suitable as a power source suitable for high power and large current applications. In the following example, an embodiment applied to a power supply device for driving an electric vehicle will be described.
[Embodiment 1]

The power supply device 100 according to the first embodiment of the present invention is shown in FIGS. 1 to 5, respectively. In these figures, FIG. 1 is a perspective view showing a power supply device 100 according to the first embodiment, FIG. 2 is an exploded perspective view of the power supply device 100 of FIG. 1, and FIG. 3 is a plan view of the power supply device 100 of FIG. 1 shows a horizontal cross-sectional view of the power supply device 100 of FIG. 1 on the IV-IV line, and FIG. 5 shows a vertical cross-sectional view of the power supply device 100 of FIG. 1 on the V-V line. The power supply device 100 shown in these figures fastens a battery laminate 10 in which a plurality of secondary battery cells 1 are laminated, a pair of end plates 20 covering both end faces of the battery laminate 10, and end plates 20 to each other. A plurality of fastening members 15 and an insulating insulating sheet 30 interposed between each of the plurality of fastening members 15 and the battery laminate 10 are provided.
(Battery laminate 10)

As shown in FIGS. 1 to 2, the battery laminate 10 is connected to a plurality of secondary battery cells 1 having positive and negative electrode terminals 2 and electrode terminals 2 of the plurality of secondary battery cells 1. A bus bar (not shown) for connecting a plurality of secondary battery cells 1 in parallel and in series is provided. A plurality of secondary battery cells 1 are connected in parallel or in series via these bus bars. The secondary battery cell 1 is a secondary battery that can be charged and discharged. In the power supply device 100, a plurality of secondary battery cells 1 are connected in parallel to form a parallel battery group, and a plurality of parallel battery groups are connected in series so that a large number of secondary battery cells 1 are connected in parallel and in series. Be connected. In the power supply device 100 shown in FIGS. 1 to 2, a plurality of secondary battery cells 1 are laminated to form a battery laminate 10. Further, a pair of end plates 20 are arranged on both end faces of the battery laminate 10. The ends of the fastening members 15 are fixed to the end plates 20 to each other, and the laminated secondary battery cells 1 are fixed in a pressed state.
(Secondary battery cell 1)

The secondary battery cell 1 is a square battery having a quadrangular outer shape of a main surface having a wide surface and having a constant cell thickness CD, and is thinner than the width. Further, the secondary battery cell 1 is a secondary battery that can be charged and discharged, and is a lithium ion secondary battery. However, the present invention does not specify the secondary battery cell as a square battery, nor does it specify a lithium ion secondary battery. As the secondary battery cell, all rechargeable batteries, for example, a non-aqueous electrolyte secondary battery other than the lithium ion secondary battery, a nickel hydrogen secondary battery cell, and the like can also be used.

As shown in FIGS. 2 to 5, in the secondary battery cell 1, an electrode body in which positive and negative electrode plates are laminated is housed in an outer can 1a, filled with an electrolytic solution, and airtightly sealed. The outer can 1a is formed into a square cylinder that closes the bottom, and the opening above the outer can 1a is hermetically closed by a metal plate sealing plate 1b. The outer can 1a is manufactured by deep drawing a metal plate such as aluminum or an aluminum alloy. The sealing plate 1b is made of a metal plate such as aluminum or an aluminum alloy, like the outer can 1a. The sealing plate 1b is inserted into the opening of the outer can 1a, irradiates the boundary between the outer periphery of the sealing plate 1b and the inner circumference of the outer can 1a with a laser beam, and the sealing plate 1b is laser welded to the outer can 1a. It is fixed airtightly.
(Electrode terminal 2)

As shown in FIG. 2, the secondary battery cell 1 has a sealing plate 1b, which is a top surface, as a terminal surface 1X, and positive and negative electrode terminals 2 are fixed to both ends of the terminal surface 1X. The electrode terminal 2 has a cylindrical protrusion. However, the protruding portion does not necessarily have to be cylindrical, and may be polygonal or elliptical.

The positions of the positive and negative electrode terminals 2 fixed to the sealing plate 1b of the secondary battery cell 1 are such that the positive electrode and the negative electrode are symmetrical. As a result, as shown in FIGS. 2 to 3, the secondary battery cells 1 are vertically inverted and stacked, and the electrode terminals 2 of the positive electrode and the negative electrode that are adjacent to each other are connected by a bus bar to form two adjacent batteries. The next battery cells 1 can be connected in series. The present invention does not specify the number of secondary battery cells constituting the battery laminate and the connection state thereof. The number of secondary battery cells constituting the battery laminate and the connection state thereof can be variously changed, including other embodiments described later.
(Battery laminate 10)

The plurality of secondary battery cells 1 are laminated so that the thickness direction of each secondary battery cell 1 is the stacking direction to form the battery laminate 10. In the battery laminate 10, a plurality of secondary battery cells 1 are laminated so that the terminal surface 1X provided with the positive and negative electrode terminals 2 and the sealing plate 1b in FIGS. 1 to 2 are flush with each other.

The battery laminate 10 may have an insulating spacer 16 interposed between the secondary battery cells 1 stacked adjacent to each other. The insulating spacer 16 is made of an insulating material such as resin in the form of a thin plate or sheet. The insulating spacer 16 has a plate shape having a size substantially equal to the facing surface of the secondary battery cell 1. The insulating spacers 16 can be laminated between the secondary battery cells 1 adjacent to each other to insulate the adjacent secondary battery cells 1 from each other. As the spacer arranged between the adjacent secondary battery cells, a spacer having a shape in which a flow path of a cooling gas is formed between the secondary battery cell and the spacer can also be used. Further, the surface of the secondary battery cell can be covered with an insulating material. For example, the surface of the outer can excluding the electrode portion of the secondary battery cell may be heat-welded with a shrink tube such as PET resin. In this case, the insulating spacer may be omitted. Further, in a power supply device in which a plurality of secondary battery cells are connected in multiple parallel and multiple series, an insulating spacer is interposed between the secondary battery cells connected in series to insulate them, while they are connected in parallel to each other. Since there is no voltage difference between the adjacent outer cans of the secondary battery cells, the insulating spacer between these secondary battery cells can be omitted.

Further, in the power supply device 100 shown in FIG. 2, end plates 20 are arranged on both end faces of the battery laminate 10. An end face spacer 17 may be interposed between the end plate 20 and the battery laminate 10 to insulate them. The end face spacer 17 can also be manufactured in the form of a thin plate or sheet with an insulating material such as resin.

In the power supply device 100 according to the first embodiment, in the battery laminate 10 in which the plurality of secondary battery cells 1 are laminated to each other, the electrode terminals 2 of the plurality of secondary battery cells 1 adjacent to each other are connected to each other by a bus bar. A plurality of secondary battery cells 1 are connected in parallel and in series. Further, the bus bar holder may be arranged between the battery laminate 10 and the bus bar. By using the bus bar holder, a plurality of bus bars can be arranged at a fixed position on the upper surface of the battery laminate while insulating the plurality of bus bars from each other and insulating the terminal surface of the secondary battery cell from the bus bar.

The bus bar is manufactured into a predetermined shape by cutting and processing a metal plate. As the metal plate constituting the bus bar, a metal having low electric resistance and light weight, for example, an aluminum plate or a copper plate, or an alloy thereof can be used. However, for the metal plate of the bus bar, other metals with low electric resistance and light weight and alloys thereof can also be used.
(End plate 20)

As shown in FIGS. 1 to 4, the end plates 20 are arranged at both ends of the battery laminate 10 and are fastened via a pair of left and right fastening members 15 arranged along both side surfaces of the battery laminate 10. Will be done. The end plates 20 are both ends of the secondary battery cell 1 of the battery laminate 10 in the stacking direction, and are arranged outside the end face spacer 17 to sandwich the battery laminate 10 from both ends.
(Step 20b)

The end plate 20 forms a stepped portion 20b for locking the locking block 15b provided on the fastening member 15 in a state of being fastened by the fastening member 15. The step portion 20b is formed in a size and shape that can lock the locking block 15b of the fastening member 15 described later. In the example of FIG. 2, a flange-shaped step portion 20b is formed so that the end plate 20 has a T-shape in a horizontal cross-sectional view. Further, an end plate screw hole 20c is opened in the vicinity of the step portion 20b.
(Fastening member 15)

Both ends of the fastening member 15 are fixed to end plates 20 arranged on both end faces of the battery laminate 10. The end plate 20 is fixed by a plurality of fastening members 15, and the battery laminate 10 is fastened in the stacking direction. As shown in FIGS. 2, 6 and the like, each fastening member 15 is made of metal having a predetermined width and a predetermined thickness along the side surface of the battery laminate 10 and faces both side surfaces of the battery laminate 10. Have been placed. A metal plate such as iron, preferably a steel plate, can be used for the fastening member 15. The fastening member 15 made of a metal plate is bent by press molding or the like to form a predetermined shape.

As shown in the exploded perspective view of FIG. 6, the fastening member 15 includes a fastening main surface 15a and a block-shaped locking block 15b. The fastening main surface 15a is a plate-shaped member, which is bent in a U-shape at the top and bottom to form a bent piece 15d. The upper and lower bent pieces 15d cover the upper and lower surfaces of the battery laminate 10 from the corners on the left and right side surfaces of the battery laminate 10.

The locking blocks 15b are fixed to both sides of the fastening main surface 15a, respectively. The locking block 15b has a plate shape having a predetermined thickness, and is fixed in a posture of projecting inward of the fastening main surface 15a. With the fastening member 15 connected to the end plate 20, the locking block 15b is locked to the stepped portion 20b provided on the end plate 20, and the fastening member 15 is arranged at fixed positions on both sides of the battery laminate 10. The locking block 15b is fixed to the fastening main surface 15a by welding such as spot welding or laser welding.

In the state where the end plate 20 is fastened, the locking block 15b opens a fastening side through hole 15b so as to coincide with the end plate screw hole 20c. Further, the fastening main surface 15a has an opening of the fastening main surface side through hole 15ac at a position corresponding to the fastening side through hole 15bc. The fastening side through hole 15bc and the fastening main surface side through hole 15ac are designed to match with the locking block 15b fixed to the fastening main surface 15a.

A plurality of fastening side through holes 15bc opened in the locking block 15b are arranged along the extension direction of the locking block 15b. Similarly, a plurality of through holes 15ac on the fastening main surface side are opened so as to be along the end edge of the fastening main surface 15a or the extension direction of the locking block 15b. A plurality of end plate screw holes 20c are also formed along the side surface of the end plate 20 accordingly.

The locking block 15b is fixed to the outer peripheral surface of the end plate 20 via a plurality of bolts 15f. The fixing of the fastening main surface 15a, the locking block 15b, and the end plate 20 is not necessarily limited to screwing using bolts, and may be a pin, a rivet, or the like.

The fastening main surface 15a and the locking block 15b can be made of iron, an iron alloy, SUS, aluminum, an aluminum alloy, or the like. Further, the locking block 15b can have a width of 10 mm or more in the battery stacking direction. Furthermore, the end plate 20 can be made of metal. Preferably, the locking block 15b and the fastening main surface 15a are made of the same metal. As a result, welding of the locking block 15b and the fastening main surface 15a can be easily performed.

In this way, the fastening member 15 is not bent from the left and right ends in the longitudinal direction, that is, in the direction of the laminated layer of the battery laminate 10 and screwed from the main surface side of the end plate 20, but is shown in FIGS. 1 to 4. As shown, the fastening member 15 has a flat plate shape in the stacking direction of the battery laminate 10, and has a locking structure and a screw by the locking block 15b and the stepped portion 20b without providing a bent portion for locking to the end plate 20. By fastening the battery laminate 10, the rigidity can be increased and the risk of breakage due to expansion of the secondary battery cell 1 can be alleviated.

The power supply device 100 in which a large number of secondary battery cells 1 are laminated is formed by connecting end plates 20 arranged at both ends of a battery laminate 10 composed of the plurality of secondary battery cells 1 with fastening members 15. It is configured to restrain the secondary battery cell 1 of the above. By restraining a plurality of secondary battery cells 1 via end plates 20 and fastening members 15 having high rigidity, malfunctions due to expansion, deformation, relative movement, and vibration of the secondary battery cells 1 due to charge / discharge and deterioration are caused. Etc. can be suppressed.
(Insulation sheet 30)

Further, an insulating sheet 30 is interposed between the fastening member 15 and the battery laminate 10. The insulating sheet 30 is made of an insulating material such as resin, and insulates between the metal fastening member 15 and the battery cell. The insulating sheet 30 shown in FIG. 2 and the like is composed of a flat plate 31 that covers the side surface of the battery laminate 10 and bent covering portions 32 provided above and below the flat plate 31. The bent covering portion 32 is bent in a U shape from the flat plate 31 so as to cover the bent piece 15d of the fastening member 15, and then further folded. Thereby, by covering the bent piece 15d from the upper surface to the side surface and the lower surface with the insulating bent covering portion, it is possible to avoid unintended conduction between the secondary battery cell 1 and the fastening member 15.

Further, the bent piece 15d presses the upper surface and the lower surface of the secondary battery cell 1 of the battery laminate 10 via the bent covering portion. As a result, each secondary battery cell 1 is pressed from the vertical direction by the bent piece 15d and held in the height direction, and even if vibration, impact, or the like is applied to the battery laminate 10, each secondary battery cell 1 is pressed. It can be maintained so that it does not shift in the vertical direction.

When the surface of the battery laminate or the battery laminate is insulated, for example, when the secondary battery cell is housed in an insulating case, covered with a heat-shrinkable tube made of resin, or fastened. If the surface of the member is coated with an insulating paint or coating, or if the fastening member is made of an insulating material, the insulating sheet can be unnecessary. Further, as for the insulating sheet, if it is not necessary to consider the insulation from the bent piece of the fastening member on the lower surface side of the battery laminate, the bent covering portion may be formed only on the upper end side. For example, the case where the secondary battery cell is covered with a heat-shrinkable tube is applicable. Further, the insulating sheet may be configured to be used in combination with the bus bar holder for holding the bus bar described above.
(Space SP)

As shown in FIGS. 1, 4, and the like, a space SP is formed in an intermediate portion of the battery laminate in the stacking direction. By providing the space SP in the stacking direction of the secondary battery cells 1 in this way, even if the battery laminate 10 expands in the stacking direction, the space SP becomes narrower and the change can be absorbed. The space SP is preferably arranged in the center of the battery laminate 10 in the stacking direction. By doing so, the changes in the battery laminate 10 can be collectively absorbed at one central location, and the displacement of the battery laminate 10 can be suppressed. For example, the amount of movement of the total terminals of the battery laminate 10 can be suppressed, and the load applied to the fixed portion of the total terminals due to the movement can be reduced. In the example of FIG. 1, since 11 secondary battery cells 1 are stacked, a space SP is arranged between the 5 secondary battery cells 1 and the 6 secondary battery cells 1.
(Spring member 40)

Further, a spring member 40 is arranged in this space SP. A configuration example of the spring member 40 is shown in the perspective view of FIG. 7. The spring member 40 shown in this figure is provided with pressing plates 42 on both sides thereof. The spring member 40 is urged to press the battery laminate 10 in the stacking direction of the secondary battery cell 1. With such a configuration, the spring member 40 can maintain the fastened state of the secondary battery cell 1 while absorbing the displacement at the time of expansion in the space SP provided in the stacking direction. In the example of FIG. 7, the spring member 40 is fixed to substantially the center of the main surface of the pressing plate 42.
(Press plate 42)

The pressing plates 42 are each formed to have substantially the same size as the side surface of the outer can of the secondary battery cell 1. The pressing plate 42 disperses the stress transmitted from the spring member 40 and uniformly presses the side surface of the secondary battery cell 1. The pressing plate 42 is made of a material having sufficient strength. It is preferably composed of a resin material having an insulating property. As a result, insulation can be ensured when a metal spring is used for the spring member 40.

The pressing plate 42 of FIG. 7 forms a spring holding portion 44 for fixing the spring member 40. The spring holding portion 44 is formed in a cylindrical shape having an outer diameter larger than the outer diameter of the coil spring, and fixes the periphery of the coil spring. In the example of FIG. 7, the pressing plate 42 is a resin member in which both sides of the spring member 40 are insert-molded by the spring holding portion 44. As a result, the spring member 40 can be stably fixed to the pressing plate 42.

If the thickness of the spring holding portion 44 is large, the amount of expansion of the battery laminate 10 in the space SP is limited. On the other hand, in order to firmly fix the spring member 40 to the pressing plate 42, a certain length is required. Therefore, the thickness of the spring holding portion 44 is designed in consideration of the expansion amount of the battery laminate 10 in the space SP and the fixing strength of the spring member 40. The thickness of the spring holding portion 44 is adjusted to, for example, 1 mm to 50 mm.

Alternatively, the pressing plate 42 may be made of a metal plate. In this case, since it is necessary to insulate from the battery laminate 10, for example, an insulating member is interposed between the pressing plate 42 and the end face of the battery laminate 10.
(Stopper 46)

The two pressing plates 42 are separated in parallel via the spring member 40. Further, a stopper 46 may be provided between the pressing plates 42. The stopper 46 defines a minimum value at which the width between the pressing plates 42 does not become shorter than this. For example, as in the power supply device 200 according to the second embodiment shown in the horizontal sectional view of FIG. 8, the stoppers 46 are fixed to the corners of one of the pressing plates 42, respectively. Each stopper 46 is projected in a rod shape, and the tip thereof is a flat surface. Thereby, the length WP of the stopper 46 is defined as the minimum width of the space SP, and the spring member 40 can be protected so as not to exceed the lower limit of the compressed state.

By providing the pressing plates 42 on both sides of the spring member 40 in this way, the pressing force can be exerted with uniform surface pressure on both sides of the spring member 40, and the spring member 40 arranged in the middle of the battery laminate 10 can be used. The pressed state can be maintained while absorbing the amount of deformation. That is, as shown in the perspective view of FIG. 9, when the secondary battery cell 1 expands, the width W1 of the space SP becomes narrower, so that the battery laminate 10 absorbs the deformation that becomes longer, and the spring member in the space SP. The 40 keeps the fastened state by pressing the left and right sides in the middle of the battery laminate 10 via the pressing plate 42. On the other hand, when the expanded secondary battery cell 1 is restored to its original state as shown in FIG. 10, the spring member 40 moves left and right in the middle of the battery laminate 10 so that the width W2 of the space SP becomes large. By pressing, the fastened state of the battery laminate 10 can be maintained.

The spring member 40 is preferably made of a metal member. In the example of FIG. 7, it is a coil spring. However, the spring member 40 is not limited to the coil spring, and other elastic bodies can be appropriately used. For example, the elastic body may be composed of a leaf spring. The elastic body of the leaf spring is interposed in the middle of the battery laminate 10 by the pressing plate 42 by bending the leaf spring, which is the spring member 40B, into a chevron shape, for example, as in the power supply device 300 according to the third embodiment shown in FIG. It is a mode to make it. Alternatively, as in the power supply device 400 according to the fourth embodiment shown in FIG. 12, the spring member 40C which is curved outward from the pressing plate 42 may be used. Alternatively, the spring member 40D may be composed of a disc spring as in the power supply device according to the fifth embodiment shown in FIG.

Further, in the example of FIG. 7 and the like, an example in which only one spring member 40 is provided has been described, but as in the power supply device according to the sixth embodiment shown in FIG. 14, a plurality of spring members 40E are provided at different positions on the pressing plate 42. It may be configured to be provided in.

As described above, the number of stacked secondary battery cells 1 can be arbitrarily adjusted. For example, as in the power supply device 700 shown in the perspective view of FIG. 15, the spring member 40 may be provided in the middle of the battery laminate 10 in which a large number of secondary battery cells 1 (36 in this case) are laminated. In order to obtain more output, multiple power supply devices may be used in combination. For example, in an electric vehicle, a plurality of power supply devices in which a fixed number of secondary battery cells are stacked are connected in series or in parallel to increase the output and capacity. .. On the other hand, there is a strong demand for miniaturization and weight reduction of power supply devices. In the configuration in which the space is provided in the stacking direction of the secondary battery cells, the total length of the power supply device is increased by the amount of the space provided. When a plurality of such power supply devices are connected, the number of spaces is accumulated by the number of power supply devices, and the entire device becomes large. For example, as shown in FIG. 16, when the power supply device 800 in which the spring member 40 is arranged between the end face of the battery laminate 10 and the end plate 20, such power supply devices 800 are arranged in series, that is, secondary. If the battery cells 1 are arranged in a straight line in the stacking direction, the entire device becomes longer by the number of space SPs. Therefore, as shown in FIG. 15, the space SP is provided not at the end face of the secondary battery cell 1 but in the middle, and the intermediate end plate is omitted, and all the secondary battery cells 1 are integrally laminated. By sharing the space SP provided in the stacking direction, the number of spaces can be reduced, and the end plate can be omitted, so that the total length of the entire device can be shortened.

The power supply device 100 described above restrains the plurality of secondary battery cells 1 by connecting the end plates 20 arranged at both ends of the battery laminate 10 in which the plurality of secondary battery cells 1 are laminated by the fastening member 15. .. By restraining a plurality of secondary battery cells 1 via end plates 20 and fastening members 15 having high rigidity, malfunctions due to expansion, deformation, relative movement, and vibration of the secondary battery cells 1 due to charge / discharge and deterioration are caused. Etc. can be suppressed. Further, the secondary battery cell 1 is provided with the spring member 40 while absorbing the change in the length of the battery laminate 10 in the stacking direction due to the expansion and contraction of the secondary battery cell 1 by the space SP provided in the stacking direction. By urging in the direction of fastening, the rattling due to the provision of the space SP can be suppressed, and the deformation of the secondary battery cell 1 can be tolerated while being stably held.

As described above, according to the power supply device 100 according to the present embodiment, the stress that tends to spread in the battery stacking direction caused by the expansion of the secondary battery cell 1 is locked to the stepped portion 20b in addition to the fastening portion itself. It is applied to each member of engagement by the block 15b, welding of the fastening portion and the locking block 15b, and screwing by the bolt 15f. Therefore, by increasing the rigidity of each of these members and appropriately dispersing the stress, it is possible to realize a power supply device 100 that can increase the rigidity as a whole and cope with the expansion and contraction of the secondary battery cell 1.

The above power supply device 100 can be used as a power source for a vehicle that supplies electric power to a motor that drives an electric vehicle. As the electric vehicle equipped with the power supply device 100, an electric vehicle such as a hybrid vehicle or a plug-in hybrid vehicle that runs on both an engine and a motor, or an electric vehicle that runs only on a motor can be used, and is used as a power source for these vehicles. Will be done. In addition, in order to obtain the electric power for driving the electric vehicle, a large number of the above-mentioned power supply devices 100 are connected in series or in parallel to construct a large-capacity, high-output power supply device to which a necessary control circuit is added. do.
(Power supply for hybrid vehicles)

FIG. 17 shows an example in which the power supply device 100 is mounted on a hybrid vehicle traveling by both an engine and a motor. The vehicle HV equipped with the power supply device 100 shown in this figure is driven by a vehicle body 91, an engine 96 for driving the vehicle body 91, a motor 93 for traveling, and these engines 96 and a motor 93 for traveling. It includes wheels 97, a power supply device 100 that supplies power to the motor 93, and a generator 94 that charges the battery of the power supply device 100. The power supply device 100 is connected to the motor 93 and the generator 94 via the DC / AC inverter 95. The vehicle HV runs on both the motor 93 and the engine 96 while charging and discharging the battery of the power supply device 100. The motor 93 is driven to drive the vehicle in a region where the engine efficiency is poor, for example, when accelerating or traveling at a low speed. The motor 93 is driven by being supplied with electric power from the power supply device 100. The generator 94 is driven by the engine 96 or by regenerative braking when braking the vehicle to charge the battery of the power supply device 100. As shown in FIG. 17, the vehicle HV may include a charging plug 98 for charging the power supply device 100. By connecting the charging plug 98 to an external power source, the power supply device 100 can be charged.
(Power supply for electric vehicles)

Further, FIG. 18 shows an example in which the power supply device 100 is mounted on an electric vehicle traveling only by a motor. The vehicle EV equipped with the power supply device 100 shown in this figure supplies electric power to the vehicle main body 91, the traveling motor 93 for running the vehicle main body 91, the wheels 97 driven by the motor 93, and the motor 93. It includes a power supply device 100 to be supplied and a generator 94 for charging the battery of the power supply device 100. The power supply device 100 is connected to the motor 93 and the generator 94 via the DC / AC inverter 95. The motor 93 is driven by being supplied with electric power from the power supply device 100. The generator 94 is driven by the energy used for regenerative braking of the vehicle EV to charge the battery of the power supply device 100. Further, the vehicle EV is provided with a charging plug 98, and the charging plug 98 can be connected to an external power source to charge the power supply device 100.
(Power supply device for power storage device)

Furthermore, the present invention does not specify the use of the power supply device as the power supply of the motor that drives the vehicle. The power supply device according to the embodiment can also be used as a power source for a power storage device that charges and stores a battery with electric power generated by solar power generation, wind power generation, or the like. FIG. 19 shows a power storage device in which the battery of the power supply device 100 is charged by the solar cell 82 to store electricity.

The power storage device shown in FIG. 19 charges the battery of the power supply device 100 with the electric power generated by the solar cell 82 arranged on the roof, rooftop, or the like of a building 81 such as a house or a factory. This power storage device uses the solar cell 82 as a power source for charging, charges the battery of the power supply device 100 with the charging circuit 83, and then supplies electric power to the load 86 via the DC / AC inverter 85. Therefore, this power storage device has a charge mode and a discharge mode. In the power storage device shown in the figure, the DC / AC inverter 85 and the charging circuit 83 are connected to the power supply device 100 via the discharge switch 87 and the charging switch 84, respectively. ON / OFF of the discharge switch 87 and the charge switch 84 is switched by the power controller 88 of the power storage device. In the charging mode, the power controller 88 switches the charging switch 84 to ON and the discharge switch 87 to OFF to allow charging from the charging circuit 83 to the power supply device 100. Further, when charging is completed and the battery is fully charged, or when the capacity is charged to a predetermined value or more, the power controller 88 turns off the charging switch 84 and turns on the discharge switch 87 to switch to the discharge mode, and the power supply device 100 Allows discharge from to load 86. Further, if necessary, the charge switch 84 can be turned on and the discharge switch 87 can be turned on to supply power to the load 86 and charge the power supply device 100 at the same time.

Further, although not shown, the power supply device can also be used as a power source for a power storage device that charges and stores a battery by using midnight power at night. A power supply device charged with midnight power can be charged with midnight power, which is surplus power of a power plant, and output power in the daytime when the power load is large, so that the peak power in the daytime can be limited to a small value. In addition, the power supply can also be used as a power source for charging with both solar cell output and midnight power. This power supply device can effectively utilize both the electric power generated by the solar cell and the late-night electric power, and can efficiently store electricity while considering the weather and power consumption.

The above-mentioned power storage system includes a backup power supply device that can be mounted in a rack of a computer server, a backup power supply device for a wireless base station such as a mobile phone, a power storage power supply for home or factory use, a power supply for street lights, and the like. It can be suitably used for power storage devices combined with solar cells, backup power sources for traffic lights and traffic indicators for roads, and the like.

The power supply device according to the present invention and the vehicle provided with the power supply device are suitably used as a power source for a large current used for a power source of a motor for driving an electric vehicle such as a hybrid vehicle, a fuel cell vehicle, an electric vehicle, and an electric motorcycle. can. For example, a power supply device for a plug-in type hybrid electric vehicle, a hybrid type electric vehicle, an electric vehicle, or the like that can switch between an EV driving mode and an HEV driving mode can be mentioned. In addition, a backup power supply that can be mounted in a computer server rack, a backup power supply for wireless base stations such as mobile phones, a power storage device for home use and factories, a power supply for street lights, etc. , Can also be used as appropriate for backup power supplies such as traffic lights.

100, 200, 300, 400, 700, 800 ... Power supply device 1 ... Secondary battery cell 1X ... Terminal surface 1a ... Exterior can 1b ... Seal plate 2 ... Electrode terminal 10 ... Battery laminate 15 ... Fastening member 15a ... Fastening main surface 15b ... Locking block 15d ... Folded piece 15ac ... Fastening main surface side through hole 15bc ... Fastening side through hole 15f ... Bolt 16 ... Insulation spacer 17 ... End face spacer 20 ... End plate 20b ... Step portion 20c ... End plate screw hole 30 ... Insulation sheet 31 ... Flat plate 32 ... Folded covering 40, 40B, 40C, 40D, 40E ... Spring member 42 ... Press plate 44 ... Spring holding part 46 ... Stopper 81 ... Building 82 ... Solar battery 83 ... Charging circuit 84 ... Charging Switch 85 ... DC / AC inverter 86 ... Load 87 ... Discharge switch 88 ... Power controller 91 ... Vehicle body 93 ... Motor 94 ... Generator 95 ... DC / AC inverter 96 ... Engine 97 ... Wheel 98 ... Charging plug 900 ... Power supply device 901 ... Secondary battery cell 902 ... Spacer 903 ... End plate 904 ... Bind bar SP ... Space W1, W2 ... Space width WP ... Stopper length HV, EV ... Vehicle

Claims (10)

Multiple secondary battery cells with square outer cans,
A pair of end plates covering both end faces of the battery laminate in which the plurality of secondary battery cells are laminated, and
A plurality of fastening members extending along the stacking direction of the plurality of secondary battery cells, arranged on opposite side surfaces of the battery laminate, and fastening the end plates to each other.
It is a power supply device equipped with
A space is formed in the intermediate portion of the battery laminate in the stacking direction.
A power supply device including a spring member urged to press the stacking direction of the battery laminate in the space. The power supply device according to claim 1, further
A power supply device including pressing plates for fixing the spring member on both sides of the spring member. The power supply device according to claim 2.
A power supply device in which the pressing plate is a resin member in which the spring member is insert-molded. The power supply device according to claim 2 or 3.
A power supply device in which the spring member is fixed to the center of the pressing plate. The power supply device according to any one of claims 1 to 4.
A power supply device in which the space is arranged in the center of the battery laminate in the stacking direction. The power supply device according to any one of claims 1 to 5.
A power supply device in which the spring member is a coil spring. The power supply device according to any one of claims 1 to 5.
A power supply device in which the spring member is a leaf spring. The power supply device according to any one of claims 1 to 7.
A power supply device provided with a plurality of the spring members. A vehicle provided with the power supply device according to any one of claims 1 to 8.
It includes the power supply device, a traveling motor to which electric power is supplied from the power supply device, a vehicle main body on which the power supply device and the motor are mounted, and wheels driven by the motor to drive the vehicle main body. vehicle. A power storage device including the power supply device according to any one of claims 1 to 8.
The power supply device and a power supply controller that controls charging / discharging to the power supply device are provided, and the power supply controller enables charging of the secondary battery cell by electric power from the outside and the second. A power storage device that controls the next battery cell to be charged.

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