Power supply device

Abstract

This power supply device comprises: a plurality of battery blocks, each of which is provided with a plurality of secondary battery cells; and a plurality of bus bar plates that, among the plurality of battery blocks, connect any one of a plurality of secondary battery cells constituting one battery block to any one of a plurality of secondary battery cells constituting another battery block. The plurality of battery blocks each comprise a plurality of battery units each composed of a plurality of secondary battery cells. The plurality of bus bar plates are arranged across the plurality of battery blocks, electrically connect the plurality of battery units included in one battery block to the plurality of battery units included in the other battery block, respectively, and mechanically connect the plurality of battery blocks to each other.

Description

power supply

[0001] The present disclosure relates to a power supply device formed by connecting a plurality of battery blocks each including a plurality of secondary battery cells.

[0002] Power supply devices incorporating a large number of rechargeable secondary battery cells have been developed. Such power supply devices are used as power sources for electric vehicles, electric heavy machinery, and the like, as stationary power storage devices for backup power sources for servers, and for home, business, and factory use. In particular, in recent years, there has been a demand for higher capacity power supply devices, and power supply devices incorporating a greater number of secondary battery cells have been adopted. In such power supply devices, overall capacity can be increased by connecting battery blocks each including multiple secondary battery cells in series or in parallel using metal bus bars.

[0003] Power supply devices that connect multiple battery blocks use fasteners to physically connect the battery blocks. However, structures that use fasteners to connect the battery blocks have the problem of increasing the device's size and reducing its energy density relative to its volume. Furthermore, the need for fasteners increases the number of parts and manufacturing processes, resulting in higher manufacturing costs.

[0004] Special Publication No. 2021-503157

[0005] One object of the present disclosure is to provide a power supply device that is formed by connecting multiple battery blocks each having a multiple number of secondary battery cells, and that does not require the preparation of additional fasteners for connecting the battery blocks together, and that can have a small external size while simplifying the configuration.

[0006] Note that the description of these objectives and problems does not preclude the existence of other objectives and problems. Furthermore, one embodiment of the present disclosure does not necessarily solve all of these problems. Furthermore, problems other than these can be extracted from the description of the specification, drawings, and claims of the present disclosure.

[0007] A power supply device according to an aspect of the present disclosure includes a plurality of battery blocks, each including a plurality of secondary battery cells, and a plurality of bus bar plates that connect any one of the plurality of secondary battery cells constituting one of the plurality of battery blocks to any one of the plurality of secondary battery cells constituting the other battery blocks. The plurality of battery blocks include a plurality of battery units, each of which is composed of a plurality of secondary battery cells, and the plurality of bus bar plates are arranged across the plurality of battery blocks to electrically connect the plurality of battery units included in one battery block to the plurality of battery units included in the other battery blocks, respectively, and to mechanically couple the plurality of battery blocks together.

[0008] The power supply device of the present disclosure does not require separate fasteners for connecting multiple battery blocks each having multiple secondary battery cells, and the external dimensions of the power supply device can be made smaller while simplifying the configuration.

[0009] FIG. 1 is a perspective view of a power supply device according to a first embodiment of the present disclosure. FIG. 2 is a rear perspective view of the power supply device shown in FIG. 1. FIG. 3 is an exploded perspective view of the power supply device shown in FIG. 1. FIG. 4 is a right side view of the power supply device shown in FIG. 1. FIG. 5 is a left side view of the power supply device shown in FIG. 1. FIG. 6 is an exploded perspective view of a battery block of the power supply device shown in FIG. 1. FIG. 7 is a schematic configuration diagram of the power supply device shown in FIG. 1. FIG. 8 is a right side view of a power supply device according to a third embodiment of the present disclosure. FIG. 9 is a left side view of the power supply device shown in FIG. 10. FIG. 10 is a schematic configuration diagram of the power supply device shown in FIG. 11. FIG. 12 is a right side view of a power supply device according to a fourth embodiment of the present disclosure. FIG. 13 is a schematic configuration diagram of the power supply device shown in FIG. 14. FIG. 15 is a left side view of the power supply device shown in FIG. 16. FIG. 17 is a left side view of the power supply device shown in FIG. 18. FIG. 19 is an equivalent circuit diagram of the power supply devices shown in FIGS. 15 to 18. FIG. 20 is a perspective view of a power supply device according to a comparative example. FIG. 21 is a rear perspective view of the power supply device shown in FIG. 20. FIG. 21 is a schematic configuration diagram of the power supply device shown in FIG. 20.

[0010] First, we will explain one key feature of the present disclosure. A power supply device equipped with a large number of secondary battery cells can achieve overall high capacity by stacking and connecting multiple battery blocks, each of which includes multiple secondary battery cells, in multiple tiers. An example of a power supply device with multiple stacked and connected battery blocks is shown in FIGS. 20 to 22 . The power supply device 90 shown in these figures has two battery blocks 91, each of which includes multiple secondary battery cells, stacked in two tiers, connected and fixed together. Each battery block 91 has lead plates 95 connected to the electrodes at both the top and bottom of the multiple secondary battery cells to connect the secondary battery cells in parallel, and the two upper and lower lead plates 95 are connected by bus bar plates 93 to connect the multiple secondary battery cells in series. As shown in the figures, this battery block 91 has multiple rows of lead plates 95 arranged in parallel on the top and bottom surfaces of a rectangular box-shaped battery holder 92, and multiple rows of bus bar plates 93 arranged on the side surfaces of the battery block 91 to electrically connect the upper and lower lead plates 95.

[0011] This power supply device 90 has battery blocks 91 stacked in two layers, one above the other, and the stacked battery blocks 91 are connected and fixed to each other at both ends via fasteners 98. The fasteners 98 shown in the figure are metal plates that connect and fix the battery holders 92 of the stacked battery blocks 91 to each other. A structure like this that uses fasteners to connect the battery blocks to each other has the problem of increased size and reduced energy density per volume. Furthermore, the need for fasteners to mechanically connect the battery blocks to each other increases the number of parts and manufacturing processes, resulting in higher manufacturing costs.

[0012] Furthermore, the power supply device 90 shown in the figure connects multiple battery blocks 91 in series to increase the output voltage, but in a structure in which multiple battery blocks 91 are connected in series by stacking them one on top of the other, the potential difference between opposing secondary battery cells becomes large on the total output side of the series-connected battery blocks 91, so measures were required to prevent short circuits between opposing battery blocks 91 when the device was submerged in water. For this reason, this power supply device required the placement of insulating members 99, such as insulating plates, between opposing battery blocks 91, as shown in Figure 22. The present disclosure was developed to solve the above problems.

[0013] A power supply device according to one embodiment of the present disclosure is a power supply device comprising a plurality of battery blocks, each comprising a plurality of secondary battery cells, and a plurality of bus bar plates that connect one of the plurality of secondary battery cells constituting one of the plurality of battery blocks to one of the plurality of secondary battery cells constituting another of the plurality of battery blocks, wherein the plurality of battery blocks comprises a plurality of battery units, each of which is composed of a plurality of secondary battery cells, and the plurality of bus bar plates are arranged across the plurality of battery blocks to electrically connect the plurality of battery units included in one battery block to the plurality of battery units included in the other battery blocks, respectively, and also to mechanically link the plurality of battery blocks together.

[0014] According to the above configuration, the bus bar plates arranged across the battery blocks electrically connect the battery units in one battery block to the battery units in the other battery blocks, and also mechanically connect the battery blocks together. Therefore, the bus bar plates that electrically connect the battery units in the battery blocks also serve as fasteners that mechanically connect the battery blocks together, enabling the battery blocks to be reliably connected and fastened together. This eliminates the need for separate fasteners that were previously required to fasten the battery blocks together, and allows the power supply device to be made smaller while simplifying the configuration.

[0015] In a power supply device according to another embodiment of the present disclosure, multiple battery blocks are stacked with their sides aligned, and the multiple battery blocks are connected to each other on both sides of the battery blocks by multiple bus bar plates.

[0016] According to the above configuration, multiple battery blocks stacked with their sides aligned are connected to each other by multiple bus bar plates on both side surfaces of the battery blocks. This makes it possible to physically connect the battery blocks by arranging multiple bus bar plates along the side surfaces of the multiple battery blocks stacked on top of each other, and makes it possible to use the multiple bus bar plates to connect the battery blocks not only electrically but also mechanically.

[0017] In another embodiment of the power supply device of the present disclosure, a battery block includes a battery holder that holds multiple rechargeable battery cells in a parallel orientation and that holds end electrodes provided at both ends of the multiple rechargeable battery cells in a coplanar arrangement, the battery holder having a side surface that serves as an arrangement surface for arranging multiple bus bar plates, and the end electrodes at both ends of the multiple rechargeable battery cells arranged in a coplanar arrangement are connected by lead plates to form a battery unit. The lead plates have connection portions at either end for connecting to the bus bar plates, and the connection portions are located on the arrangement surface of the battery holder. The bus bar plates located on the arrangement surface are stacked on the connection portions, and fixing screws that pass through the bus bar plates and the connection portions are fastened to the battery holder, electrically connecting the bus bar plates to the battery unit and mechanically coupling the bus bar plates to the battery holder.

[0018] In this specification, "arranged in the same plane" does not necessarily mean that the components are arranged on the same plane, but is used in a broad sense to include a state in which the components are slightly shifted from the same plane, for example, a state in which the components are arranged in a parallel posture or a slightly inclined posture.

[0019] The above configuration has the advantage that the bus bar plate can be easily and reliably electrically and mechanically connected to the battery block. This is because the power supply battery block includes a battery holder that holds multiple rechargeable battery cells in place, the side of the battery holder serves as the mounting surface for the bus bar plate, the connection parts at the ends of the lead plates that connect the end surface electrodes of the rechargeable battery cells arranged on the same plane are located on the mounting surface, and fixing screws that penetrate the end connecting parts and connection parts of the bus bar plate located on the mounting surface are fastened to the battery holder, electrically connecting the bus bar plate to the battery unit and mechanically connecting the bus bar plate to the battery holder.

[0020] In a power supply device according to another embodiment of the present disclosure, the plurality of battery blocks includes a first battery block and a second battery block stacked on top of each other, and the lead plates include a first lead plate connecting first electrodes of the plurality of rechargeable battery cells and a second lead plate connecting second electrodes of the plurality of rechargeable battery cells opposite the first electrodes. The battery unit is a parallel unit formed by connecting the plurality of rechargeable battery cells in parallel via the first lead plate and the second lead plate, and a plurality of bus bar plates alternately connect the plurality of battery units included in the first battery block and the plurality of battery units included in the second battery block in series.

[0021] In the power supply devices described above, parallel units, each consisting of multiple parallel-connected secondary battery cells, are connected in series via bus bar plates. Because the total current of the parallel units flows through the bus bar plates, the current in the bus bar plates increases. Therefore, to reduce electrical resistance, the bus bar plates are preferably made of wide, thick metal plates, i.e., metal plates with a large cross-sectional area. Because metal plates with a large cross-sectional area have high rigidity, they can mechanically connect multiple battery blocks with high strength.

[0022] In a power supply device according to another embodiment of the present disclosure, each battery block has a first lead plate connected to a first electrode disposed on a first main surface of the battery block and a second lead plate connected to a second electrode disposed on a second main surface opposite the first main surface, and the first battery block and the second battery block are stacked in such a position that the second main surface of the first battery block faces the second main surface of the second battery block to form an assembled battery. The first lead plates of the plurality of battery units included in the first battery block are connected to the second lead plates of the plurality of battery units included in the second battery block by bus bar plates, and the second lead plates of the plurality of battery units included in the first battery block are connected to the first lead plates of the plurality of battery units included in the second battery block by bus bar plates.

[0023] In a power supply device according to another embodiment of the present disclosure, each battery block has a first lead plate connected to a first electrode disposed on a first main surface of the battery block and a second lead plate connected to a second electrode disposed on a second main surface opposite the first main surface, and the first battery block and the second battery block are stacked in a position where the second main surface of the first battery block faces the first main surface of the second battery block to form an assembled battery. The first lead plates of the plurality of battery units included in the first battery block are connected to the second lead plates of the plurality of battery units included in the second battery block by bus bar plates, and the second lead plates of the plurality of battery units included in the first battery block are connected to the first lead plates of the plurality of battery units included in the second battery block by bus bar plates.

[0024] In a power supply device according to another embodiment of the present disclosure, the bus bar plate includes a first plate disposed on a first side surface of the battery block and a second plate disposed on a second side surface of the battery block opposite the first side surface, the first battery block and the second battery block have n battery units arranged from a first end surface toward an opposite second end surface, and the opposing battery blocks are configured such that, on the first side surface, the first to nth battery units of the first battery block and the first to nth battery units of the second battery block are connected in series via the respective first plates, and on the second side surface, the second to nth battery units of the first battery block and the first to (n-1)th battery units of the second battery block are connected in series via the respective second plates, and the first battery unit and the nth battery unit have output terminals connected to the electrode side not connected to the bus bar plate, where n is a natural number of 2 or greater.

[0025] According to the above connection structure, the battery units included in the first battery block and the battery units included in the second battery block are connected between opposing battery blocks in order from the first end face side toward the second end face side, which has the advantage of being able to connect multiple battery units in series with the simplest structure.

[0026] Furthermore, the above configuration has the advantage of simplifying the physical structure for insulating the battery blocks by reducing the potential difference between the opposing surfaces of the battery blocks, which means that insulating plates that are placed on the opposing surfaces of the battery blocks to protect them from submersion can be omitted.

[0027] In a power supply device according to another embodiment of the present disclosure, a plurality of battery blocks have a non-connection area on a first side surface, in which no first plate is arranged, extending along the length of the first side surface, and a circuit board or an output bus bar is arranged in the non-connection area.

[0028] According to the above configuration, the plurality of battery blocks have a non-connection area on the first side surface, in which the first plate is not arranged, extending along the length of the first side surface, so that a circuit board or an output bus bar can be arranged in the non-connection area.

[0029] In a power supply device according to another embodiment of the present disclosure, the plurality of battery blocks have a non-connection area on the second side surface, in which the second plate is not arranged, extending along the length of the second side surface, and a circuit board or an output bus bar is arranged in the non-connection area.

[0030] According to the above configuration, the plurality of battery blocks have a non-connection area on the second side surface, in which the second plate is not arranged, extending along the length of the second side surface, so that a circuit board or an output bus bar can be arranged in the non-connection area.

[0031] In a power supply device according to another embodiment of the present disclosure, a first battery block and a second battery block have a plurality of battery units arranged from a first end face toward an opposite second end face, and the odd-numbered battery units in the first battery block and the even-numbered battery units in the second battery block are alternately connected in series via a plurality of bus bar plates, and the odd-numbered battery units in the second battery block and the even-numbered battery units in the first battery block are alternately connected in series via a plurality of bus bar plates, and the battery units arranged closest to the second end face are connected in series via a connecting bus bar.

[0032] According to the above connection structure, when connecting the battery units included in the first battery block and the battery units included in the second battery block in order from the first end face side, the odd-numbered battery units of one battery block are alternately connected with the even-numbered battery units of the other battery block, and then folded back at the second end face side to connect all the battery units in series, which has the advantage that the positive and negative output terminals can be positioned on the first end face side.

[0033] In a power supply device according to another embodiment of the present disclosure, each battery block is arranged so that the positive and negative polarities of the multiple battery units are alternately reversed, and the first battery block and the second battery block are stacked on top of each other so that the polarities of the opposing electrodes of the battery units arranged in opposing positions on the opposing surfaces are opposite to each other, and the first battery block and the second battery block connect adjacent battery units in series on the surface opposite to the opposing surface, and also connect battery units opposing each other on the opposing surfaces in series via multiple bus bar plates.

[0034] According to the above configuration, each battery block has multiple battery units arranged so that the positive and negative polarities are alternately reversed, and adjacent battery units are connected in series on the opposing surfaces of the stacked battery blocks, while the battery units arranged so that the positive and negative polarities are opposite are connected on the opposing surfaces by multiple bus bar plates.This means that all battery units made up of multiple secondary battery cells can be connected in series with a simple structure, and the stacked battery blocks can also be mechanically linked by the bus bar plates.

[0035] A power supply device according to another embodiment of the present disclosure further includes an outer case that houses an assembled battery formed by connecting a plurality of battery blocks with a plurality of bus bar plates, and each of the plurality of secondary battery cells has a gas release valve on one of its electrode surfaces that opens in response to an increase in internal pressure, and each of the plurality of battery blocks holds the plurality of secondary battery cells in a position where the electrode surface with the gas release valve faces the outer case.

[0036] With the above configuration, even if the gas exhaust valve of one of the secondary battery cells operates and high-pressure gas is released from the electrode surface, the orientation of the battery cell facing the outer case prevents high-pressure gas from being sprayed onto the electrode surfaces of other battery blocks, thereby increasing safety.

[0037] In a power supply device according to another embodiment of the present disclosure, the potential difference between the electrode surfaces of the opposing secondary battery cells between adjacent battery blocks among a plurality of battery blocks is set to be equal to or less than the electromotive force of one secondary battery cell.

[0038] The above configuration has the advantage of simplifying the physical structure for insulating the battery blocks by reducing the potential difference between the opposing surfaces of the battery blocks. In conventional structures, the potential difference between the electrodes of adjacent battery units becomes large, requiring an insulating plate to protect against saltwater submersion. However, with this configuration, an innovative fastening method reduces the potential difference between adjacent battery units, making it possible to eliminate the need for an insulating plate.

[0039] In another embodiment of the power supply device of the present disclosure, the plurality of battery blocks includes a first battery block and a second battery block stacked on top of each other, the lead plates include a first lead plate connecting first electrodes of the plurality of secondary battery cells and a second lead plate connecting second electrodes of the plurality of secondary battery cells opposite the first electrodes, the battery unit is a parallel unit formed by connecting the plurality of secondary battery cells in parallel via the first lead plate and the second lead plate, and the plurality of bus bar plates connect the battery units included in the first battery block and the second battery block that are arranged opposite each other in parallel, and connect the battery units that are arranged adjacent to each other in series.

[0040] With this configuration, of the battery units included in the first battery block and the battery units included in the second battery block, the battery units facing each other are connected in parallel, while the battery units adjacent to each other are connected in series, so the capacity of the power supply device can be increased while mechanically linking the first battery block and the second battery block. In particular, the total output voltage of the linked first battery block and second battery block can be made equal to the total output of each of the first battery block and second battery block, so high capacity can be achieved simply and easily without adjusting the voltage on the load side during use.

[0041] In a power supply device according to another embodiment of the present disclosure, a first battery block and a second battery block have a plurality of battery units arranged from a first end face toward an opposite second end face, and the opposing battery blocks are connected by a bus bar plate on a first side surface of the battery block 10, with the first lead plate of the (2n-1)th battery unit and the second lead plate of the 2nth battery unit being connected by a bus bar plate, and on a second side surface of the battery block 10, the first lead plate of the 2nth battery unit and the second lead plate of the (2n+1)th battery unit being connected by a bus bar plate, where n is a natural number.

[0042] The power supply device described above has the advantage of being able to eliminate and equalize current imbalances between the secondary battery cells of parallel units while connecting battery units in parallel between stacked battery blocks. This is because adjacent battery units are connected in series while opposing battery units are connected in parallel between opposing battery blocks via bus bar plates arranged alternately on the first and second sides of the battery blocks. With this structure, current is passed through each battery unit from the first side to the second side, or from the second side to the first side. This configuration connects the multiple secondary battery cells that make up each battery unit to the bus bar plates via lead plates with the same electrical resistance, effectively eliminating current imbalances between the secondary battery cells.

[0043] [Embodiment 1] Figures 1 to 7 show a power supply device 100 according to embodiment 1. Figure 1 is a perspective view of the power supply device, Figure 2 is a rear perspective view of the power supply device of Figure 1, Figure 3 is an exploded perspective view of the power supply device of Figure 1, Figures 4 and 5 are right and left side views of the power supply device of Figure 1, Figure 6 is an exploded perspective view of the battery block, and Figure 7 is a schematic diagram showing the connection state of the battery blocks.

[0044] The power supply device 100 shown in Fig. 1 includes a plurality of battery blocks 10 each including a plurality of secondary battery cells 1, and a plurality of bus bar plates 3 that connect one of the plurality of secondary battery cells 1 constituting one of the plurality of battery blocks 10 to one of the plurality of secondary battery cells 1 constituting another of the plurality of battery blocks 10. The plurality of battery blocks 10 include a plurality of battery units 2, each of which is composed of a plurality of secondary battery cells 1. The plurality of bus bar plates 3 are arranged across the plurality of battery blocks 10, electrically connecting the plurality of battery units 2 included in one battery block 10 to the plurality of battery units 2 included in the other battery blocks 10, and mechanically coupling the plurality of battery blocks 10 together.

[0045] The power supply device 100 shown in the figure includes a first battery block 10A and a second battery block 10B stacked on top of each other as multiple battery blocks 10. The multiple battery blocks 10 are stacked with their side surfaces 12 aligned, and the multiple battery blocks 10 are connected to each other at both side surfaces 12 of the battery blocks 10 by multiple bus bar plates 3. The multiple battery blocks 10 are preferably arranged with their side surfaces 12 aligned on the same plane, but may be arranged slightly offset from the same plane. The power supply device 100 shown in the schematic configuration diagram of FIG. 7 has an assembled battery 9, made up of multiple battery blocks 10 connected by multiple bus bar plates 3, housed in an exterior case 8.

[0046] (Battery Block 10) The battery block 10 shown in Figures 1 to 7 has an overall outline that is approximately rectangular parallelepiped. As shown in Figures 1 to 3, the rectangular parallelepiped battery block 10 has main surfaces 11 arranged at the top and bottom, side surfaces 12 arranged on both sides, and end surfaces 13 arranged at the front and back. Specifically, the battery block 10 has a pair of main surfaces 11 consisting of a first main surface 11A and a second main surface 11B arranged parallel to each other, a pair of side surfaces 12 consisting of a first side surface 12A and a second side surface 12B arranged parallel to each other and connecting the side edges of the first main surface 11A and the second main surface 11B, and a pair of end surfaces 13 consisting of a first end surface 13A and a second end surface 13B arranged parallel to each other and connecting the end edges of the pair of main surfaces 11 and the pair of side surfaces 12.

[0047] The battery block 10 includes a battery holder 20 that holds each rechargeable battery cell 1 in a predetermined orientation and in a fixed position. The battery holder 20 holds multiple rechargeable battery cells 1 in a parallel orientation, with the end electrodes at both longitudinal ends of the multiple rechargeable battery cells 1 aligned flush. The battery holder 20 is a molded body made of insulating material such as plastic, and includes a cylindrical insertion section 21 into which each rechargeable battery cell 1 is inserted and positioned. The battery holder 20 shown in FIG. 6 is divided into a first holder 20A and a second holder 20B midway along the battery cell length. The multiple rechargeable battery cells 1 are sandwiched and positioned in their fixed positions with both ends inserted into the cylindrical insertion sections 21. Both side surfaces of the battery holder 20 serve as placement surfaces 22 on which multiple bus bar plates 3 are positioned.

[0048] Furthermore, the battery block 10 configures a battery unit 2 by connecting the end electrodes at both ends of multiple rechargeable battery cells 1 arranged on the same plane with lead plates 5. Each battery block 10 includes multiple battery units 2 arranged in multiple rows, with adjacent battery units 2 connected by bus bar plates 3. The battery block shown in FIG. 6 configures a battery unit 2 by arranging 11 rechargeable battery cells 1 in a parallel orientation in a single row along the diameter, and connecting the upper and lower end electrodes with lead plates 5 in two battery rows arranged front to back. Adjacent battery rows are arranged close to each other, with the rechargeable battery cells 1 of one row positioned in the valley between the other battery row. This battery block 10 includes a total of 154 rechargeable battery cells 1 and is configured with seven battery units 2, each consisting of a front-to-back arrangement of these rechargeable battery cells 1.

[0049] 3, adjacent secondary battery cells 1 are arranged in two rows in the longitudinal direction of the lead plates 5 and connected in parallel by a first lead plate 5A arranged on the top surface and a second lead plate 5B arranged on the bottom surface. However, the battery unit can also have secondary battery cells arranged in a single row in the longitudinal direction of the lead plates, or in three or more rows, and connected in parallel by the first and second lead plates.

[0050] (Secondary Battery Cell 1) The secondary battery cell 1 is a non-aqueous electrolyte secondary battery cell such as a lithium-ion battery. However, this disclosure does not limit the secondary battery cell 1 to a lithium-ion battery; all currently used and future developed secondary batteries, including other non-aqueous electrolyte secondary batteries and nickel-metal hydride batteries, can be used. The secondary battery cell 1 shown in FIG. 6 is a cylindrical battery with end electrodes on both ends. However, the battery pack of this disclosure does not limit the battery to a cylindrical battery. This is because rechargeable prismatic batteries and other types of batteries can also be used as battery cells. The secondary battery cell 1 has a first electrode 1A, which is one end face, as the positive electrode, and a second electrode 1B, which is the other end face, as the negative electrode. The secondary battery cell 1 has a gas release valve (not shown) on one electrode that opens in response to an increase in internal pressure. The secondary battery cell shown in the figure has a release valve on the first electrode 1A, which is the positive electrode.

[0051] (Lead Plates 5) The lead plates 5 include a first lead plate 5A that connects the first electrodes 1A of the multiple secondary battery cells 1 and a second lead plate 5B that connects the second electrodes 1B of the multiple secondary battery cells 1. The battery unit 2 is a parallel unit formed by connecting multiple secondary battery cells 1 in parallel via the first lead plate 5A and the second lead plate 5B. The multiple battery units 2 included in the first battery block 10A and the multiple battery units 2 included in the second battery block 10B are connected in series via multiple bus bar plates 3.

[0052] To connect the battery units 2 in series between adjacent battery blocks 10, the lead-plates 5 have connection portions 5x at one end of the first lead-plate 5A and the second lead-plate 5B for connection to the bus bar plate 3. The first lead-plate 5A and the second lead-plate 5B have connection portions 5x at opposite ends of the lead-plate 5A and the bus bar plate 3. The configuration, shape, size, etc. of the connection portions 5x are not specified, but the connection portions 5x can be formed, for example, by folding one end of the lead-plate 5 back and bending it 90 degrees to a shape or angle that facilitates connection between the lead-plate 5, which is positioned horizontally, and the bus bar plate 3, which is positioned vertically. As shown in FIG. 6 , the first lead-plate 5A has a connection portion 5x at one end, and the second lead-plate 5B has a connection portion 5x at the other end. The connection portions 5x of the first lead-plate 5A and the second lead-plate 5B are located at opposite ends of the battery unit 2.

[0053] The connection portions 5x are disposed on the placement surface 22 of the battery holder 20, and are connected to the ends of the bus bar plates 3 when the bus bar plates 3 are placed on the placement surface 22. The ends of the bus bar plates 3 are stacked on the connection portions 5x, and fixing screws 4 that pass through the ends of the bus bar plates 3 and the connection portions 5x are fixed to the battery holder 20, electrically connecting the bus bar plates 3 to the battery unit 2 and mechanically linking the bus bar plates 3 to the battery holder 20. Although not shown, the battery holder 20 can be secured by embedding reinforcing collars at the connection positions between the connection portions 5x and the bus bar plates 3 to enable the fixing screws 4 to be screwed in more firmly.

[0054] (Busbar Plate 3) The busbar plate 3 is a thin, conductive metal plate such as an aluminum plate, a nickel plate, or a copper plate. Because the total current of the battery unit 2 flows through the busbar plate 3, a metal plate with a larger current capacity than the lead plate 5 is used. The busbar plate 3 can be made of the same metal material as the lead plate 5. Furthermore, the busbar plate 3 also serves as a component that mechanically connects the stacked battery blocks together. Therefore, the metal busbar plate 3 must be strong enough to hold the connected battery blocks 10 in place. The material, thickness, and width of the busbar plate 3 are determined taking these factors into consideration. Here, the busbar plate 3, which connects multiple parallel units in series, is required to have low electrical resistance. This requirement can be met by using a metal plate with a large cross-sectional area for the busbar plate 3, which advantageously increases the rigidity of the busbar plate at the same time.

[0055] The above-described power supply device 100 alternately connects multiple battery units 2 included in a first battery block 10A and multiple battery units 2 included in a second battery block 10B in series as described below. Each battery block 10 shown in FIGS. 4, 5, and 7 has a first lead plate 5A connected to a first electrode 1A arranged on the first main surface 11A of the battery block 10, and a second lead plate 5B connected to a second electrode 1B arranged on the second main surface 11B. The illustrated power supply device 100 forms a battery pack 9 by stacking the first battery block 10A and the second battery block 10B such that the second main surface 11B of the first battery block 10A faces the second main surface 11B of the second battery block 10B. That is, the stacked battery blocks 10 are stacked such that the negative electrodes, i.e., the second electrodes 1B, face each other.

[0056] 5, in this power supply device 100, the first lead plates 5A of the multiple battery units 2 included in the first battery block 10A are connected to the second lead plates 5B of the multiple battery units 2 included in the second battery block 10B on the second side surface 12B of the battery block 10. Also, as shown in FIG. 4, the second lead plates 5B of the multiple battery units 2 included in the first battery block 10A are connected to the first lead plates 5A of the multiple battery units 2 included in the second battery block 10B on the first side surface 12A of the battery block 10.

[0057] The bus bar plate 3 shown in Figures 4 and 5 includes a first plate 3A arranged on the first side surface 12A of the battery block 10 and a second plate 3B arranged on the second side surface 12B of the battery block 10. Seven battery units 2 are arranged in each of the first and second battery blocks 10A and 10B, from the first end surface 13A toward the opposite second end surface 13B. As shown in Figure 4 , the first through seventh battery units 2 of the first battery block 10A and the first through seventh battery units 2 of the second battery block 10B are connected in series on the first side surface 12A via the first plates 3A, respectively. The first plates 3A shown in the figures are arranged vertically in a straight line and connect to the second lead plates 5B of the battery units 2 of the first battery block 10A and the first lead plates 5A of the battery units 2 of the second battery block 10B, connecting these battery units 2 in series. 5, the second to seventh battery units 2 of the first battery block 10A and the first to sixth battery units 2 of the second battery block 10B are connected in series on the second side surface 12B via the second plates 3B. The second plates 3B shown in the figure are inclined and plate-like, arranged vertically, and connect to the first lead-plates 5A of the battery units 2 of the first battery block 10A and the second lead-plates 5B of the battery units 2 of the second battery block 10B, connecting these battery units 2 in series.

[0058] Furthermore, in this power supply device 100, the output terminal 15 is connected to the electrode side to which the bus bar plate 3 is not connected of the first battery unit 2 in the first battery block 10A and the seventh battery unit 2 in the second battery block 10B. That is, in this power supply device 100, the first electrode 1A side of the first battery unit 2 in the first battery block 10A and the second electrode 1B side of the seventh battery unit 2 in the second battery block 10B are each connected to the output terminal 15. By alternately connecting the battery units 2 of the stacked battery blocks 10 in series from the first end face 13A side toward the second end face 13B side, this power supply device 100 can connect all of the battery units 2 in series while maintaining a simple structure.

[0059] Furthermore, in this power supply device 100, the battery units 2 of opposing battery blocks 10 are alternately connected in series via the first plates 3A arranged on the first side surface 12A of the battery block 10 and the second plates 3B arranged on the second side surface 12B, so that current flows through the multiple secondary battery cells 1 constituting each battery unit 2 from the first side surface 12A toward the second side surface 12B, or from the second side surface 12B toward the first side surface 12A. For example, in the power supply device 100 shown in Figures 1 to 7, during discharge, current flows through the multiple battery units 2 included in the first battery block 10A from the first side surface 12A toward the second side surface 12B, and current flows through the multiple battery units 2 included in the second battery block 10B from the second side surface 12B toward the first side surface 12A. Therefore, the bus bar plate 3 is connected to the multiple secondary battery cells 1 that make up each battery unit 2 via lead plates with the same electrical resistance, which has the advantage of eliminating and equalizing the current imbalance between the secondary battery cells.

[0060] Furthermore, as shown in Figure 7, this power supply device 100 can keep the potential difference between the electrode surfaces of the opposing rechargeable battery cells 1 between adjacent battery blocks 10 below the electromotive force of a single rechargeable battery cell 1. This has the advantage of simplifying the physical structure for insulating between battery blocks. This structure reduces the potential difference between adjacent battery units 2, making it possible to eliminate the need for insulating members such as insulating plates.

[0061] The power supply device 100 shown in FIG. 7 further includes an exterior case 8 that houses an assembled battery 9, which is made up of multiple battery blocks 10 connected by bus bar plates 3. The battery block shown in the figure includes multiple rechargeable battery cells 1 each equipped with a gas release valve on the first electrode 1A side that opens in response to an increase in internal pressure. That is, in this power supply device 100, the electrode surfaces of the multiple rechargeable battery cells 1 in the stacked battery blocks 10, each equipped with a gas release valve, face the exterior case 8. Therefore, even if an abnormality occurs in one of the rechargeable battery cells 1, causing the gas release valve to open in response to an increase in internal pressure and inject high-temperature gas, the gas release valve faces the exterior case 8, reducing adverse effects on the other rechargeable battery cells 1.

[0062] Furthermore, as shown in Figures 1 and 2, in the power supply device 100 described above, when multiple battery blocks 10 are connected, a non-connection area 17 where no first plate 3A is located is formed on the first side surface 12A along the length of the first side surface 12A, and a non-connection area 17 where no second plate 3B is located is formed on the second side surface 12B along the length of the second side surface 12B. In this power supply device 100, a circuit board 18 for detecting the voltage of each battery unit 2 can be located in this non-connection area 17. In addition, this power supply device 100 can also have an output bus bar 19 located in the non-connection area 17. As shown by the dashed lines in the figures, a structure in which the output bus bar 19 is located in the non-connection area 17 allows the positive and negative output terminals 15 to be located on a single end surface 13.

[0063] 8 and 9, the power supply device can also be configured such that the first battery block 10A and the second battery block 10B are stacked and connected so that the second main surface 11B of the first battery block 10A faces the first main surface 11A of the second battery block 10B. This power supply device 200 is stacked between the opposing battery blocks 10 so that the negative electrode, which is the second electrode 1B of the first battery block 10A, faces the positive electrode, which is the first electrode 1A of the second battery block 10B.

[0064] 4 and 5, this power supply device 200 also connects opposing battery blocks 10 in series on the first side surface 12A, with the first to seventh battery units 2 of the first battery block 10A and the first to seventh battery units 2 of the second battery block 10B connected in series via the first plates 3A, respectively, and with the second side surface 12B connecting the second to seventh battery units 2 of the first battery block 10A and the first to sixth battery units 2 of the second battery block 10B connected in series via the second plates 3B, respectively. As shown in FIG. 8, in this power supply device 200, the second lead plates 5B of the battery units 2 of the first battery block 10A and the first lead plates 5A of the battery units 2 of the second battery block 10B are positioned close to each other in the center on the first side surface 12A, allowing the opposing connection portions 5x to be connected over the shortest distance by the first plates 3A. Furthermore, as shown in Figure 9, in this power supply device, the first lead plate 5A of the battery unit 2 of the first battery block 10A and the second lead plate 5B of the battery unit 2 of the second battery block 10B are arranged vertically apart on the second side surface 12B, so that the second plate 3B can be made into a plate-like shape that extends vertically in an inclined position, and these can be connected in series.

[0065] In this power supply device 200, the battery units 2 of opposing battery blocks 10 are alternately connected in series via first plates 3A arranged on the first side 12A of the battery blocks 10 and second plates 3B arranged on the second side 12B, so that current flows through the multiple secondary battery cells 1 constituting each battery unit 2 from the first side 12A toward the second side 12B (first battery block 10A during discharge) or from the second side 12B toward the first side 12A (second battery block 10B during discharge). Therefore, the multiple secondary battery cells 1 constituting each battery unit 2 are connected to the bus bar plates 3 via lead plates with the same electrical resistance, which has the advantage of eliminating and equalizing current imbalances between the secondary battery cells.

[0066] In this power supply device 200, when multiple battery blocks 10 are connected, non-connection areas 17 where the first plate 3A is not placed are formed at the upper and lower ends of the first side surface 12A along the length of the second side surface, and these non-connection areas 17 can also be used to place a circuit board for voltage detection or an output bus bar.

[0067] (Embodiment 3) Furthermore, the power supply device can also connect the multiple battery units 2 included in the first battery block 10A and the multiple battery units 2 included in the second battery block 10B in the following structure shown in Figures 10 to 12. In the power supply device 300 shown in the figures, the first battery block 10A and the second battery block 10B are also stacked in an orientation in which the second main surface 11B of the first battery block 10A faces the second main surface 11B of the second battery block 10B.

[0068] 10 to 12, seven battery units 2 are arranged from a first end surface 13A toward an opposite second end surface 13B. As shown in Fig. 11, between the opposing battery blocks 10, odd-numbered battery units 2 in the first battery block 10A and even-numbered battery units 2 in the second battery block 10B are alternately connected in series via multiple bus bar plates 3, and odd-numbered battery units 2 in the second battery block 10B and even-numbered battery units 2 in the first battery block 10A are alternately connected in series via multiple bus bar plates 3.

[0069] Specifically, as shown in FIG. 11 , on the second side surface 12B, the second lead plates 5B of the battery units 2 arranged in the first, third, and fifth positions in the first battery block 10A and the first lead plates 5A of the battery units 2 arranged in the second, fourth, and sixth positions in the second battery block 10B are connected in series via the second plates 3B, respectively, and the second lead plates 5B of the battery units 2 arranged in the third, fifth, and seventh positions in the second battery block 10B and the first lead plates 5A of the battery units 2 arranged in the second, fourth, and sixth positions in the first battery block 10A are connected in series via the second plates 3B, respectively.

[0070] As shown in FIG. 10 , on the first side surface 12A, the first lead plates 5A of the first, third, and fifth battery units 2 in the second battery block 10B and the second lead plates 5B of the second, fourth, and sixth battery units 2 in the first battery block 10A are connected in series via the first plates 3A, respectively, and the first lead plates 5A of the third, fifth, and seventh battery units 2 in the first battery block 10A and the second lead plates 5B of the second, fourth, and sixth battery units 2 in the second battery block 10B are connected in series via the first plates 3A, respectively.

[0071] The first plate 3A and second plate 3B shown in these figures are inclined and have a plate-like shape that extends vertically, and are connected to the first lead-plate 5A and second lead-plate 5B of corresponding battery units 2, connecting these battery units 2 in series. The battery units 2 located closest to the second end face are also connected in series via a connection bus bar 16. In Figure 10, the second lead-plate 5B of the seventh battery unit 2 in the first battery block 10A and the first lead-plate 5A of the seventh battery unit 2 in the second battery block 10B are connected in series on the first side surface 12A via a linear connection bus bar 16 that extends vertically.

[0072] The power supply device 300 of this structure has the advantage that the odd-numbered battery units 2 of one battery block 10 are alternately connected with the even-numbered battery units 2 of the other battery block 10, and all battery units 2 are connected in series by folding back at the second end face 13B side, allowing the positive and negative output terminals 15 to be positioned on the first end face 13A side.

[0073] In addition, in this power supply device 300, the battery units 2 of opposing battery blocks 10 are alternately connected in series via the first plates 3A arranged on the first side surface 12A of the battery blocks 10 and the second plates 3B arranged on the second side surface 12B of the battery blocks 10, so that current flows through the multiple secondary battery cells 1 constituting each battery unit 2 from the first side surface 12A toward the second side surface 12B, or from the second side surface 12B toward the first side surface 12A. That is, in the power supply device 300 shown in Figures 10 to 12, during discharge, current flows through the multiple battery units 2 included in the first battery block 10A from the first side surface 12A toward the second side surface 12B, and current flows through the multiple battery units 2 included in the second battery block 10B from the second side surface 12B toward the first side surface 12A. Therefore, the bus bar plate 3 is connected to the multiple secondary battery cells 1 that make up each battery unit 2 via lead plates with the same electrical resistance, which has the advantage of eliminating and equalizing the current imbalance between the secondary battery cells.

[0074] 12 also includes an exterior case 8 that houses an assembled battery 9 made up of multiple battery blocks 10 connected by bus bar plates 3, and the stacked battery blocks 10 are arranged so that the electrode surfaces equipped with gas release valves of the multiple secondary battery cells 1 face the exterior case 8. Therefore, even if an abnormality occurs in one of the secondary battery cells 1 and the gas release valve opens in response to an increase in internal pressure, spraying high-temperature gas, etc., this power supply device 300 has the advantage of reducing adverse effects on other secondary battery cells 1 because the gas release valve is positioned facing the exterior case 8.

[0075] As shown in FIG. 12 , the power supply device 300 has insulating plates 29 arranged at the opposing portions of the stacked battery blocks 10 to insulate the battery blocks 10 from each other, in order to prevent secondary battery cells 1 with a voltage difference from shorting out or the like.

[0076] Furthermore, the power supply device can be configured such that odd-numbered battery units of one battery block and even-numbered battery units of the other battery block are alternately connected as shown in Figures 10 to 12, and the first battery block and the second battery block can be stacked and connected so that the second main surface of the first battery block faces the first main surface of the second battery block as shown in Figures 8 and 9.

[0077] (Fourth Embodiment) The power supply device may also have the structure shown in Figures 13 and 14. In the power supply device 400 shown in these figures, the positive and negative polarities of the multiple battery units 2 in each battery block 10 are arranged alternately in opposite directions. Furthermore, in the power supply device 400, the first battery block 10A and the second battery block 10B are stacked one on top of the other, and the opposing electrodes of the battery units 2 arranged in opposing positions on the opposing surfaces 31 are opposite in polarity. In the first battery block 10A and the second battery block 10B, adjacent battery units 2 are connected in series via connecting lead plates 33 on the surface opposite the opposing surface 31. Furthermore, in the first battery block 10A and the second battery block 10B, the opposing battery units 2 on the opposing surfaces 31 are connected in series via multiple bus bar plates 3.

[0078] FIG. 13 shows the state in which opposing lead plates 5 on the first side 12A of the battery block 10 are connected in series via bus bar plates 3. Although not shown, opposing lead plates on the second side of the battery block 10 are also connected in series via bus bar plates. In this way, stacked battery blocks 10 are firmly connected to each other by electrically connecting opposing battery units 2 via multiple bus bar plates 3 and mechanically connecting the battery blocks 10. The bus bar plates 3 shown in the figure connect opposing battery units 2 over the shortest distance, which allows for a simple and lightweight structure. This power supply device 400 can also utilize the side areas where the bus bar plates 3 are not located as non-connected areas.

[0079] (Embodiments 5 and 6) The power supply devices according to the above embodiments are configured so that multiple parallel units of stacked battery blocks are connected in series. However, the power supply devices can also connect multiple parallel units of stacked battery blocks in series while also connecting them in parallel. The power supply devices 500 and 600 shown in FIGS. 15 to 19 are configured so that, of the multiple battery units 2 included in a first battery block 10A and the multiple battery units 2 included in a second battery block 10B, the battery units 2 that are arranged facing each other are connected in parallel, and the battery units 2 that are arranged adjacent to each other are connected in series. Here, the power supply device 500 shown in FIGS. 15 and 16 is configured so that the second main surface 11B of the first battery block 10A and the second battery block 10B face each other, and the negative electrodes, which are the second electrodes 1B, face each other. In addition, the power supply device 600 shown in Figures 17 and 18 has the first battery block 10A and the second battery block 10B stacked so that the second main surface 11B of the first battery block 10A and the first main surface 11A of the second battery block 10B are opposed to each other, and the negative electrode of the first battery block 10A and the positive electrode of the second battery block 10B are opposed to each other.

[0080] In the power supply devices 500 and 600 shown in Figures 15 to 19, seven battery units 2 are arranged in each of a first battery block 10A and a second battery block 10B, arranged from a first end surface 13A toward an opposite second end surface 13B. As shown in Figures 15 and 17, the first lead-plates 5A of the battery units 2 arranged in the first, third, and fifth positions on the first side surface 12A of the opposing battery blocks 10 are connected by bus bar plates 3 to the second lead-plates 5B of the battery units 2 arranged in the second, fourth, and sixth positions. As shown in Figures 16 and 18, the first lead-plates 5A of the battery units 2 arranged in the second, fourth, and sixth positions on the second side surface 12B of the battery blocks 10 are connected by bus bar plates 3 to the second lead-plates 5B of the battery units 2 arranged in the third, fifth, and seventh positions on the second side surface 12B of the opposing battery blocks 10. Furthermore, on the first side surface 12A, the first lead plates 5A of the seventh battery units 2 are connected by a connecting bus bar 35 and connected to the output terminal 15, and on the second side surface 12B, the second lead plates 5B of the first battery units 2 are connected by a connecting bus bar 35 and connected to the output terminal 15.

[0081] 15 and 16 includes intermediate connection portions that connect the second lead-plates 5B together, and extension portions that extend from the intermediate connection portions at an angle above and below and connect their ends to the first lead-plates 5A, resulting in a roughly dogleg shape overall. In this busbar plate 3, the intermediate connection portions that connect the second lead-plates 5B of opposing battery units 2 primarily play a role in mechanically connecting the battery blocks 10 together. However, the busbar plate 3 is not limited to the above shape, and various shapes that can connect a pair of first lead-plates and a pair of second lead-plates with a single plate are possible. For example, a structure in which a plate portion connecting the first lead-plates together and a plate portion connecting the second lead-plates together are connected by a connecting portion is also possible.

[0082] 17 and 18 has straight sections that connect the first lead-plates 5A of opposing battery units 2, straight sections that connect the second lead-plates 5B of opposing battery units 2, and connecting sections that connect these straight sections. A bus bar plate 3 of this shape connects opposing battery blocks 10 at each straight section, and also mechanically connects the battery blocks 10 at the connecting sections.

[0083] In the power supply units 500 and 600 described above, the bus bar plates 3 arranged on the first side surface 12A and the second side surface 12B can have the same shape. That is, the bus bar plate 3 used on the first side surface 12A can be moved point-symmetrically or flipped left and right and used on the second side surface 12B. This not only reduces the manufacturing cost of the bus bar plates, but also reduces the risk of incorrect connection during assembly.

[0084] In the power supply devices 500 and 600 described above, the battery units 2 included in the first battery block 10A and the battery units 2 included in the second battery block 10B are connected in parallel with the opposing battery units 2, while the adjacent battery units 2 are connected in series. This allows the total output voltage of multiple connected battery blocks 10 to be equal to the total output of each individual battery block 10. This eliminates the need for voltage adjustment with the load during use. In other words, capacity can be increased without changing the total output voltage.

[0085] Furthermore, the power supply devices 500, 600 described above have the advantage of being able to eliminate and equalize imbalances in the currents flowing through the secondary battery cells that make up parallel units between stacked battery blocks 10. This is because the opposing battery units 2 between opposing battery blocks 10 are connected in parallel, while adjacent battery units are connected in series, via bus bar plates 3 alternately arranged on the first and second sides 12A, 12B of the battery blocks 10. Figure 19 shows an equivalent circuit diagram of the power supply devices 500, 600. As shown in this diagram, the power supply devices 500, 600 connect multiple battery units 2 in parallel and series via bus bar plates 3 alternately arranged on the first and second sides 12A, 12B. Therefore, by passing current through each battery unit 2 from the first side surface 12A to the second side surface 12B, or from the second side surface 12B to the first side surface 12A, the bus bar plate 3 is connected to the multiple secondary battery cells 1 that make up each battery unit 2 via lead plates with the same electrical resistance, thereby eliminating and equalizing the current imbalance between the secondary battery cells.

[0086] In particular, the above power supply devices 500, 600 connect opposing battery units 2 in parallel between stacked battery blocks 10, resulting in a larger number of parallel-connected secondary battery cells 1 than in a single battery block 10. As described above, the greater the number of parallel-connected secondary battery cells 1, the more likely it is that a current imbalance will occur between the secondary battery cells 1 constituting the parallel-connected battery units 2. However, with the above structure, current flows evenly through the secondary battery cells 1 of each parallel-connected battery unit 2. Therefore, while the above power supply devices connect a large number of secondary battery cells in parallel, they can equalize the amount of current without imbalances in the current flowing through each secondary battery cell 1, effectively preventing deterioration of specific secondary battery cells 1 and extending the life of the power supply devices.

[0087] In the power supply devices shown in the first to sixth embodiments, the battery unit 2 has multiple secondary battery cells connected in parallel using the first lead plate 5A and the second lead plate 5B, but the battery unit can also be a series-parallel unit in which multiple secondary battery cells are connected in parallel and in series. A series-parallel unit in which multiple secondary battery cells are connected in parallel and in series connects multiple secondary battery cells in series and in series by alternately reversing the orientation of multiple secondary battery cells that make up the battery unit, and connecting electrodes with the same polarity in parallel and electrodes with opposite polarity in series to connect the multiple secondary battery cells in series and in series.

[0088] The present disclosure can be used as a power source for electric vehicles, electric heavy machinery, etc., or can be suitably used for stationary power storage applications such as power sources for power storage systems for home, business, and factory use, or as backup power sources for servers.

[0089] REFERENCE SIGNS LIST 100, 200, 300, 400, 500, 600... Power supply device 1... Secondary battery cell 1A... First electrode 1B... Second electrode 2... Battery unit 3... Bus bar plate 3A... First plate 3B... Second plate 4... Fixing screw 5... Lead plate 5A... First lead plate 5B... Second lead plate 5x... Connection portion 8... Outer case 9... Assembled battery 10... Battery block 10A... First battery block 10B... Second battery block 11... Main surface 11A... First main surface 11B... Second main surface 12... Side surface 12A... First side surface 12B... Second side surface 13... End surface 13A... First end surface 13B... Second end surface 15... Output terminal 16... Connection bus bar 17... Non-connection area 18... Circuit board 19... Output bus bar 20... Battery holder 20A... First holder 20B... Second holder 21... Insertion tube portion 22... Arrangement surface 29... Insulating plate 31... Opposing surface 33... Connecting lead plate 35... Connecting bus bar 90... Power supply device 91... Battery block 92... Battery holder 93... Bus bar plate 95... Lead plate 98... Fixing device 99... Insulating member

Claims

1. A power supply device comprising: a plurality of battery blocks each including a plurality of secondary battery cells; the plurality of battery blocks including a first battery block and a second battery block; and a plurality of bus bar plates connecting any one of the plurality of secondary battery cells constituting the first battery block to any one of the plurality of secondary battery cells constituting the second battery block, wherein the plurality of battery blocks include a plurality of battery units each composed of a plurality of the secondary battery cells, and the plurality of bus bar plates are arranged across the plurality of battery blocks to electrically connect the plurality of battery units included in the first battery block to the plurality of battery units included in the second battery block, respectively, and to mechanically link the plurality of battery blocks together.

2. A power supply device as claimed in claim 1, wherein the plurality of battery blocks are stacked with the side surfaces of each battery block aligned side by side, and the plurality of battery blocks are connected to each other on both side surfaces of the battery blocks by the plurality of bus bar plates.

3. A power supply device as claimed in claim 2, wherein each of the plurality of secondary battery cells is columnar with its axis extending in the longitudinal direction, the battery block comprises a battery holder which holds the plurality of secondary battery cells with their axes parallel to each other and which holds end electrodes at both ends of the plurality of secondary battery cells arranged in the same plane, a side of the battery holder serves as an arrangement surface for arranging the plurality of bus bar plates, and the end electrodes at both ends of the plurality of secondary battery cells arranged in the same plane are connected by lead plates to form the battery unit, the lead plate having a connection portion for connecting to the bus bar plate at one end, the connection portion being arranged on the arrangement surface of the battery holder, the bus bar plate arranged on the arrangement surface being stacked on the connection portion, and fixing screws passing through the bus bar plate and the connection portion being fixed to the battery holder, so that the bus bar plate is electrically connected to the battery unit and the bus bar plate is mechanically linked to the battery holder.

4. A power supply device as described in claim 3, wherein the plurality of battery blocks include the first battery block and the second battery block stacked on top of each other, the lead plate has a first lead plate connecting first electrodes of the plurality of secondary battery cells and a second lead plate connecting second electrodes of the plurality of secondary battery cells opposite the first electrodes, the battery unit is a parallel unit formed by connecting the plurality of secondary battery cells in parallel via the first lead plate and the second lead plate, and the plurality of bus bar plates alternately connect the plurality of battery units included in the first battery block and the plurality of battery units included in the second battery block in series.

5. A power supply device as described in claim 4, wherein each battery block has the first lead plate connected to the first electrode arranged on a first main surface side of the battery block, and the second lead plate connected to the second electrode arranged on a second main surface side opposite the first main surface, the second main surface of the first battery block faces the second main surface of the second battery block, and the first battery block and the second battery block are stacked to form an assembled battery, the first lead plates of the multiple battery units included in the first battery block are connected to the second lead plates of the multiple battery units included in the second battery block by the bus bar plate, and the second lead plates of the multiple battery units included in the first battery block are connected to the first lead plates of the multiple battery units included in the second battery block by the bus bar plate.

6. A power supply device as claimed in claim 4, wherein each battery block has the first lead plate connected to the first electrode disposed on a first main surface of the battery block, and the second lead plate connected to the second electrode disposed on a second main surface opposite the first main surface, the second main surface of the first battery block faces the first main surface of the second battery block, and the first battery block and the second battery block are stacked to form an assembled battery, the first lead plates of the multiple battery units included in the first battery block are connected to the second lead plates of the multiple battery units included in the second battery block by the bus bar plate, and the second lead plates of the multiple battery units included in the first battery block are connected to the first lead plates of the multiple battery units included in the second battery block by the bus bar plate.

7. A power supply device as claimed in claim 5 or 6, wherein the bus bar plate comprises: a first plate arranged on a first side surface of the battery block; and a second plate arranged on a second side surface of the battery block opposite the first side surface, wherein the first battery block and the second battery block have n battery units arranged from a first end surface towards an opposite second end surface, n being a natural number of 2 or more, wherein the opposing battery blocks are arranged such that, on the first side surface, the 1st to nth battery units of the first battery block and the 1st to nth battery units of the second battery block are connected in series via the first plates, respectively, and, on the second side surface, the 2nd to nth battery units of the first battery block and the 1st to (n-1)th battery units of the second battery block are connected in series via the second plates, respectively, and the 1st battery unit and the nth battery unit have output terminals connected to electrodes to which the bus bar plate is not connected.

8. A power supply device as described in claim 7, wherein the plurality of battery blocks have a non-connected area on the first side surface, where the first plate is not arranged, extending from the first end face to the second end face of the first side surface, and a circuit board or an output bus bar is arranged in the non-connected area.

9. A power supply device as described in claim 7, wherein the plurality of battery blocks have a non-connected area on the second side surface, in which the second plate is not arranged, extending from the first end face to the second end face of the second side surface, and a circuit board or the output terminal is arranged in the non-connected area.

10. A power supply device as claimed in claim 5 or 6, wherein the first battery block and the second battery block have a plurality of the battery units arranged from a first end face towards an opposite second end face, the odd-numbered battery units in the first battery block and the even-numbered battery units in the second battery block are alternately connected in series via the plurality of bus bar plates, the odd-numbered battery units in the second battery block and the even-numbered battery units in the first battery block are alternately connected in series via the plurality of bus bar plates, and the battery units arranged closest to the second end faces are connected in series via a connecting bus bar.

11. A power supply device as described in claim 4, wherein each battery block is arranged so that the positive and negative polarities of the multiple battery units are alternately in opposite directions, the first battery block and the second battery block are stacked on top of each other so that the polarities of the opposing electrodes of the battery units arranged in opposing positions on opposing surfaces facing each other are opposite, the first battery block and the second battery block connect adjacent battery units in series on the surface opposite to the opposing surface, and the battery units opposing each other on the opposing surfaces are connected in series via the multiple bus bar plates.

12. A power supply device as claimed in claim 1 or 5, further comprising an outer case for housing an assembled battery in which the plurality of battery blocks are connected by the plurality of bus bar plates, wherein the plurality of secondary battery cells are each provided with a gas exhaust valve on one of their electrode surfaces which opens in response to an increase in internal pressure, and wherein each of the plurality of battery blocks holds the plurality of secondary battery cells with the electrode surface provided with the gas exhaust valve facing the outer case.

13. A power supply device as claimed in any one of claims 1, 5 and 6, wherein the potential difference between the electrode surfaces of opposing secondary battery cells between adjacent battery blocks among said plurality of battery blocks is set to be equal to or less than the electromotive force of one secondary battery cell.

14. A power supply device as described in claim 3, wherein the plurality of battery blocks include a first battery block and a second battery block stacked on top of each other, the lead plate includes a first lead plate connecting first electrodes of the plurality of secondary battery cells and a second lead plate connecting second electrodes of the plurality of secondary battery cells opposite the first electrodes, the battery unit is a parallel unit formed by connecting the plurality of secondary battery cells in parallel via the first lead plate and the second lead plate, and the plurality of bus bar plates connect the battery units included in the first battery block and the plurality of battery units included in the second battery block that are arranged opposite each other in parallel, and connect the battery units that are arranged adjacent to each other in series.

15. A power supply device as described in claim 14, wherein the first battery block and the second battery block have a plurality of the battery units arranged from a first end face toward an opposite second end face, and the opposing battery blocks are arranged such that, on a first side of the battery block, m is a natural number, the first lead plate of the (2m-1)th battery unit and the second lead plate of the 2mth battery unit are connected by the bus bar plate, and on a second side of the battery block, the first lead plate of the 2mth battery unit and the second lead plate of the (2m+1)th battery unit are connected by the bus bar plate.

Images