Battery unit

Abstract

To provide a battery unit capable of suppressing deterioration of communication quality.SOLUTION: A battery unit 11 includes battery blocks 21, a battery monitoring device 30 that detects battery information and transmits it via wireless communication, a battery control device 40 that receives the battery information from the battery monitoring device 30 via wireless communication, and a conductive storage case 50 that houses them. The storage case 50 houses one or more battery blocks 21 inside, and is provided with a conductive closing plate 81 that closes at least one of the gap between the battery blocks 21 and the storage case 50 and the gap 25 between the battery blocks 21.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a battery unit. [Background technology]

[0002] Recently, there have been battery monitoring systems that transmit or receive battery status information via wireless communication. Such a battery monitoring system is described in Patent Document 1, for example. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-205587 Summary of the Invention [Problem to be solved by the invention]

[0004] When applying a battery monitoring system that performs wireless communication to a vehicle battery unit, it is considered to prevent external noise by making the battery case of the battery unit out of metal and housing the battery monitoring system inside the battery case.

[0005] However, even if the battery monitoring system is housed in a metal battery case, depending on the arrangement and shape of the battery cells and battery modules inside the battery case, radio wave interference may occur between the wireless communication radio waves and their reflected waves, resulting in a deterioration in communication quality.

[0006] The present invention has been made in view of the above circumstances, and a main object of the present invention is to provide a battery unit that can suppress deterioration of communication quality. [Means for solving the problem]

[0007] A battery unit for solving the above problem comprises a battery unit, a battery monitoring device that detects battery information and transmits it via wireless communication, a battery control device that receives battery information from the battery monitoring device via wireless communication, and a conductive housing that houses them, wherein one or more battery units are housed inside the housing, and the housing is equipped with a radio wave penetration suppression member that blocks at least part of the gap between the battery unit and the housing and the gap between the battery units themselves.

[0008] This configuration can prevent a portion of the radio wave from branching off and entering a gap, resulting in a reflected wave with a predetermined phase difference from the radio wave and returning. This can suppress radio wave interference and maintain good received power. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram of a vehicle. [Figure 2] FIG. 2 is a block diagram showing the configuration of a battery unit. [Figure 3] FIG. 2 is a perspective view showing the inside of the battery unit. [Figure 4] FIG. 3 is a plan view showing the inside of the battery unit. [Figure 5] FIG. 3 is a side view showing the inside of the battery unit. [Figure 6] Schematic diagram explaining the principle of radio wave interference. [Figure 7] FIG. 10 is a diagram showing the relationship between the depth dimension of a gap and the phase difference of a reflected wave. [Figure 8] A diagram showing the relationship between frequency and loss. [Figure 9] FIG. 10 is a plan view showing the inside of a battery unit according to a second embodiment. [Figure 10] FIG. 10 is a side view showing the inside of a battery unit according to a second embodiment. [Figure 11] FIG. 11 is a plan view showing the inside of a battery unit according to a third embodiment. [Figure 12] FIG. 11 is a side view showing the inside of a battery unit according to a third embodiment. [Figure 13] FIG. 10 is a plan view showing the inside of a battery unit according to a fourth embodiment. [Figure 14] FIG. 10 is a side view showing the inside of a battery unit according to a fourth embodiment. [Figure 15] FIG. 11 is a plan view showing the inside of a battery unit according to a fifth embodiment. [Figure 16] FIG. 11 is a cross-sectional view of the battery unit according to the fifth embodiment taken along line A1-A1. [Figure 17] FIG. 11 is a cross-sectional view of the battery unit according to the fifth embodiment taken along line B1-B1. [Figure 18] FIG. 13 is a plan view showing the inside of a battery unit according to a sixth embodiment. [Figure 19] FIG. 13 is a side view showing the inside of a battery unit according to a sixth embodiment. [Figure 20] FIG. 13 is a plan view showing the inside of a battery unit according to a seventh embodiment. [Figure 21] FIG. 20 is a cross-sectional view of the battery unit taken along line A2-A2 in the seventh embodiment. [Figure 22] FIG. 20 is a cross-sectional view of the battery unit according to the seventh embodiment taken along line B2-B2. [Figure 23] FIG. 10 is a perspective view showing a closure plate in a modified example. [Figure 24] FIG. 10 is a diagram showing the relationship between the width dimension of the expansion margin and loss. [Figure 25] FIG. 10 is a perspective view showing a closure plate in a modified example. [Figure 26] FIG. 10 is a perspective view showing a closure plate in a modified example. [Figure 27] FIG. 10 is a plan view showing the inside of a battery unit according to a modified example. [Figure 28] FIG. 10 is a plan view showing the inside of a battery unit according to a modified example. [Figure 29] FIG. 10 is a plan view showing the inside of a battery unit according to a modified example. [Figure 30] FIG. 10 is a side view showing the inside of a battery unit according to a modified example. [Figure 31] FIG. 10 is a plan view showing the inside of a battery unit according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the battery unit according to the present disclosure will be described in detail with reference to the drawings. Note that, among the embodiments and modifications, the same or equivalent parts in the drawings are designated by the same reference numerals, and their descriptions will not be repeated in principle. Below, we will describe the battery unit applied to a vehicle, but it can also be applied to applications other than vehicles, such as drones and other flying objects, ships, construction machinery, agricultural machinery, etc.

[0011] (First embodiment) <Vehicle> FIG. 1 is a diagram that shows a schematic configuration of a vehicle 10. The vehicle 10 is an electrically powered vehicle such as an electric vehicle (EV), a hybrid vehicle (HV), or a plug-in hybrid vehicle (PHV). The vehicle 10 includes a battery unit 11 (shown as "Battery" in FIG. 1), a power control unit (hereinafter referred to as "PCU") 12 as a power conversion device, a motor 13 (shown as "MG" in FIG. 1) as an electric load, and a vehicle ECU 14 (shown as "ECU" in FIG. 1). Note that PCU is an abbreviation for "Power Control Unit," MG is an abbreviation for "Motor Generator," and ECU is an abbreviation for "Electronic Control Unit."

[0012] The battery unit 11 is mounted on the vehicle 10 as a driving power source for the vehicle 10. In Fig. 1, the battery unit 11 is disposed, for example, in the front compartment. However, the battery unit 11 may also be disposed in the rear compartment, under the seat, under the floor, or the like.

[0013] The battery unit 11 is equipped with a battery pack 20 (described later) and is a chargeable and dischargeable DC voltage source. The battery unit 11 supplies power to the electrical loads of the vehicle 10. The battery unit 11 also converts power via the PCU 12 and supplies the power to the motor 13. The battery unit 11 is also charged via the PCU 12.

[0014] The PCU 12 performs bidirectional power conversion between the battery unit 11 and the motor 13 in accordance with a control signal from the vehicle ECU 14. The PCU 12 includes, for example, an inverter that converts DC voltage from the battery unit 11 into AC voltage to drive the motor 13, and a converter that boosts the DC voltage supplied to the inverter to a voltage equal to or higher than the output voltage of the battery unit 11.

[0015] Motor 13 is an AC rotating electric machine, such as a three-phase AC synchronous motor with a permanent magnet embedded in the rotor. Motor 13 is driven by PCU 12 to generate rotational driving force, which is transmitted to the drive wheels. Meanwhile, when braking vehicle 10, motor 13 operates as a generator and performs regenerative power generation. The electric power generated by motor 13 is supplied to battery unit 11 via PCU 12 and stored in battery pack 20.

[0016] The vehicle ECU 14 includes a CPU, ROM, RAM, input / output ports for inputting and outputting various signals, etc. The CPU loads a program stored in the ROM into the RAM and executes it. The program stored in the ROM describes the processing of the vehicle ECU 14. As an example of the main processing of the vehicle ECU 14, the vehicle ECU 14 receives information such as the voltage, current, SOC (State of Charge), and SOH (State of Health) of the battery pack 20 from the battery unit 11, and controls the PCU 12 to instruct the motor 13 to be driven and the battery unit 11 to be charged or discharged.

[0017] <Battery unit> The battery unit 11 will be described in detail. Fig. 2 is a block diagram showing the configuration of the battery unit 11, and Fig. 3 is a perspective view showing the schematic arrangement of the various elements housed inside the battery unit 11. Fig. 4 is a horizontal cross-sectional view of the battery unit 11 (a plan view of the interior of the battery unit 11) showing the schematic arrangement of the various elements housed inside the battery unit 11 when viewed from above, and Fig. 5 is a vertical cross-sectional view of the battery unit 11 (a side view of the interior of the battery unit 11) showing the schematic arrangement of the various elements housed inside the battery unit 11 when viewed from the side.

[0018] The battery unit 11 includes a battery pack 20, a junction box 60, a battery monitoring system 100, and a housing 50 (shown by a dashed line) that houses these components. The battery monitoring system 100 is a system that monitors and manages the battery state of the battery pack 20 using wireless communication. The battery monitoring system 100 includes a plurality of battery monitoring devices 30 and a battery control device 40, and wireless communication is performed between these devices. The battery monitoring devices 30 are sometimes called slave communication devices, and the battery control device 40 is sometimes called master communication device.

[0019] In this embodiment, the battery pack 20, the battery monitoring device 30, and the battery control device 40 are housed inside the housing case 50 (battery housing space), but the housing case 50 may not be provided and the battery pack 20 and the battery monitoring system 100 may be directly attached to a battery housing space provided in the vehicle body frame or the like. In other words, the vehicle body frame may be used as a housing instead of the housing case 50.

[0020] <Battery pack> The battery pack 20 includes a plurality of battery blocks 21 (sometimes referred to as a battery stack or a battery module). The battery pack 20 is configured by connecting the plurality of battery blocks 21 in series and / or parallel. Each battery block 21 includes a plurality of battery cells 22 (shown by dashed lines in FIG. 3). Each battery cell 22 is configured by a lithium-ion secondary battery, a nickel-metal hydride secondary battery, or the like. Note that a lithium-ion secondary battery is a secondary battery that uses lithium as a charge carrier, and may include not only a general lithium-ion secondary battery with a liquid electrolyte but also a so-called all-solid-state battery that uses a solid electrolyte. The battery block 21 is configured by connecting the plurality of battery cells 22 in series and / or parallel via bus bars (not shown). Note that the battery block 21 may or may not be provided, and the battery pack 20 may be configured by connecting the plurality of battery cells 22 in series and / or parallel. In this embodiment, the battery block 21 corresponds to the battery section.

[0021] The battery block 21 includes a case body 21a serving as a battery case that houses a plurality of battery cells 22. The case body 21a is made of a conductor such as metal. The case body 21a is formed in the shape of a metal box, and has a substantially rectangular parallelepiped shape.

[0022] <Junction box> The junction box 60 houses one or more relay switches 61 and the like. As shown in Fig. 2, the relay switches 61 are used to connect the battery blocks 21 (or battery cells 22) in series and / or parallel to one another. The relay switches 61 also switch between energizing and de-energizing the battery pack 20, allowing the battery units 11 to be charged or discharged. The on / off of these relay switches 61 is controlled by the battery control device 40 and the like.

[0023] <Battery monitoring device> The battery monitoring device 30 will now be described. Note that each battery monitoring device 30 has a common configuration. The battery monitoring device 30 is also called a satellite battery module (SBM), and is provided for each battery block 21, i.e., for each of a plurality of battery cells 22. As shown in FIG. 2, each battery monitoring device 30 includes a monitoring IC 31, a slave device-side wireless IC 32, and a slave device-side wireless antenna 33. These components are mounted on a monitoring circuit board 34 of the battery monitoring device 30, and are housed and fixed in an SBM case 35 (shown by a dashed line in FIG. 2) that serves as the housing for the battery monitoring device 30.

[0024] The slave device side wireless IC 32 is connected to the monitoring IC 31 by a wire, and the slave device side wireless IC 32 is connected to the slave device side wireless antenna 33 by a wire.

[0025] The monitoring IC 31, also called a cell monitoring circuit, acquires (senses) battery information of each battery cell 22 constituting the battery block 21 via a physical quantity detection sensor (not shown) or the like. The physical quantity detection sensor is, for example, a voltage sensor, a temperature sensor, a current sensor, or the like, and the battery information includes, for example, voltage information, temperature information, current information, and the like of each battery cell 22. The object monitored by the battery monitoring device 30 may be the battery block 21 or the entire battery pack 20, and may be changed as desired.

[0026] When the monitoring IC 31 receives data (control data as control information) requesting acquisition and transmission of battery information, it acquires the battery information in accordance with the control data and transmits monitoring data (control results) including at least the battery information. Note that the monitoring IC 31 may have a function of performing a fault diagnosis (self-diagnosis) of the circuitry of the battery monitoring device 30 including itself, and transmitting the monitoring data including the diagnosis results together with the acquired battery information.

[0027] The slave device side wireless IC 32 includes an RF circuit, a microcomputer, a front-end circuit, and other components (not shown) to wirelessly transmit and receive data. The slave device side wireless IC 32 has a transmission function that modulates data and oscillates at the frequency of an RF signal. At the same time, the slave device side wireless IC 32 has a reception function that demodulates received data. RF is an abbreviation for "radio frequency."

[0028] The slave-side wireless IC 32 modulates the monitoring data including the battery information received from the monitoring IC 31 and transmits it to the battery control device 40 via the slave-side wireless antenna 33. At this time, the slave-side wireless IC 32 adds data necessary for wireless communication, such as communication control information, to the monitoring data including the battery information and transmits it. Examples of data necessary for wireless communication include an identifier (ID) and an error detection code. The slave-side wireless IC 32 also has functions such as determining the data size, communication format, and schedule of communication between the battery monitoring device 30 and the battery control device 40, and detecting errors.

[0029] The slave-side wireless IC 32 also receives and demodulates data wirelessly transmitted from the battery control device 40 via the slave-side wireless antenna 33. When the slave-side wireless IC 32 receives control data including a request to acquire and transmit battery information, for example, the slave-side wireless IC 32 transmits (transfers) the control data via a wired connection to the monitoring IC 31. When the slave-side wireless IC 32 receives monitoring data including battery information from the monitoring IC 31 in response to the request, the slave-side wireless IC 32 modulates response data including the monitoring data and wirelessly transmits the response data to the battery control device 40 via the slave-side wireless antenna 33.

[0030] The slave side wireless antenna 33 converts the RF signal, which is an electrical signal, into radio waves and radiates them into space, and also receives the radio waves propagating through space and converts them into an electrical signal.

[0031] <Battery control device> The battery control device 40 is also called a battery ECU or a BMU (Battery Management Unit). The battery control device 40 is configured to be able to communicate wirelessly with each battery monitoring device 30.

[0032] 2, the battery control device 40 includes a battery control MCU 41, a parent device side wireless IC 42, and a parent device side wireless antenna 43. These components are mounted on a control circuit board 44 of the battery control device 40 and are housed and fixed in an ECU case 45 (shown by a dashed line in FIG. 2) that serves as the housing of the battery control device 40.

[0033] The base station side wireless IC 42 is connected by wire to the battery control MCU 41. The base station side wireless IC 42 is also connected by wire to the base station side wireless antenna 43.

[0034] The battery control MCU 41 is configured with a microcontroller unit (microcontroller unit) including a CPU, ROM, RAM, input / output interface, etc. The CPU of the battery control MCU 41 loads a program stored in the ROM into the RAM and executes it. The program stored in the ROM contains, for example, processes related to battery control.

[0035] As an example of the main processing of the battery control MCU 41, the battery control MCU 41 transmits control data to the battery monitoring device 30 requesting acquisition and transmission of battery information. Furthermore, the battery control MCU 41 performs various processes related to monitoring the battery pack 20, battery block 21, and battery cells 22 based on monitoring data including battery information received from the battery monitoring device 30. For example, the battery control MCU 41 may transmit monitoring results (monitoring data) to the vehicle ECU 14, which is a higher-level ECU. In this case, the battery control MCU 41 may calculate the SOC and / or SOH based on the battery information and transmit battery information including the calculated SOC and SOH to the vehicle ECU 14. Furthermore, the battery control MCU 41 controls the relay switch 61, which switches between energized and de-energized states between the battery pack 20 and the PCU 12 and the motor 13, based on the monitoring results and the like. Furthermore, the battery control MCU 41 may transmit an equalization signal to equalize the voltages of the battery cells 22. In this embodiment, the vehicle ECU 14 issues instructions to the PCU 12 to control the charging and discharging of the battery pack 20, but the battery control MCU 41 may be configured to perform this function. As described above, the battery control MCU 41 monitors and manages the battery pack 20, the battery block 21, and the battery cells 22.

[0036] The master-side wireless IC 42 includes an RF circuit, a microcomputer, a front-end circuit, and the like (not shown) for wirelessly transmitting and receiving data, similar to the slave-side wireless IC 32. The master-side wireless IC 42 has a transmission function and a reception function, similar to the slave-side wireless IC 32.

[0037] The base unit side wireless IC 42 demodulates the received monitoring data including battery information via the base unit side wireless antenna 43 and transmits the demodulated data to the battery control MCU 41. The base unit side wireless IC 42 also modulates the control data received from the battery control MCU 41 with data necessary for wireless communication, such as communication control information, and transmits the modulated data to the battery monitoring device 30 via the base unit side wireless antenna 43. The data necessary for wireless communication includes, for example, an identifier (ID) and an error detection code. The base unit side wireless IC 42 also has functions such as determining the data size, communication format, and schedule of communication between the battery monitoring device 30 and the battery control device 40, and detecting errors.

[0038] The base station side wireless antenna 43 has the same configuration and function as the slave station side wireless antenna 33. That is, the base station side wireless antenna 43 converts an RF signal, which is an electrical signal, into a radio wave and radiates it into space, and also receives the radio wave propagating through space and converts it into an electrical signal.

[0039] <Containment Case> The housing case 50 is made of a conductor such as metal. The housing case 50 is formed in the shape of a metal box, and is roughly rectangular parallelepiped. Note that the housing case 50 may be partially or entirely made of a non-conductive material such as resin. The housing case 50 houses the battery pack 20, the battery monitoring device 30, and the battery control device 40 in the internal battery housing space.

[0040] 3 to 5, the arrangement of the battery pack 20, battery monitoring device 30, battery control device 40, and junction box 60 will be briefly described. The lower surface of the housing case 50 is the mounting surface for the vehicle 10. As shown in FIG. 3, inside the roughly rectangular parallelepiped housing case 50, multiple battery blocks 21 that make up the battery pack 20 are arranged side by side in the longitudinal direction (X direction in FIG. 3). The battery blocks 21 are arranged at predetermined intervals so that predetermined gaps 25 are provided between each battery block 21. Note that these gaps 25 are recessed in the Z-direction (downward) when viewed from above (Z direction) the battery unit 11.

[0041] In each battery block 21, the battery cells 22 that make up the battery block 21 are arranged in a stacked arrangement in the short-side direction (Y direction in FIG. 3) of the accommodating case 50. Below, the long-side direction of the accommodating case 50 may be referred to as the X-direction, the short-side direction as the Y-direction, and the up-down direction as the Z-direction.

[0042] A battery monitoring device 30 is disposed on the upper surface of each battery block 21 (the surface on the +Z direction side in FIG. 3), more specifically, on the upper surface of the case body 21a of the battery block 21, and is fixed thereto with screws or the like. As a result, as shown in FIG. 5, the battery monitoring devices 30 are disposed at approximately the same position (height) in the up-down direction (Z direction). Therefore, the child device side wireless antennas 33 are also disposed at approximately the same position in the Z direction. Furthermore, as shown in FIGS. 3 and 4, each battery monitoring device 30 is disposed at approximately the center of each battery block 21 in the Y direction. Therefore, the multiple battery monitoring devices 30 and their corresponding child device side wireless antennas 33 are disposed in a straight line aligned along the X direction.

[0043] The battery control device 40 and the junction box 60 are disposed at the very ends in the longitudinal direction (X direction). In this case, the battery control device 40 is placed directly above (on the Z+ direction side of) the junction box 60. The battery control device 40 is desirably disposed so that the parent device side wireless antenna 43 is disposed near the upper surface of the battery block 21, more preferably above the upper surface. In this embodiment, as shown in FIG. 5 , the battery control device 40 is disposed in approximately the same position as the battery monitoring device 30 in the Z direction (up-down direction). More specifically, the parent device side wireless antenna 43 is disposed in approximately the same position as each child device side wireless antenna 33 in the Z direction.

[0044] The battery control device 40 is disposed at approximately the same position in the Y direction as the battery monitoring device 30, i.e., approximately in the center of the housing case 50. The base-side wireless antenna 43 is also disposed at approximately the same position in the Y direction as each of the slave-side wireless antennas 33. Therefore, as shown in FIG. 4, the battery control device 40 and the multiple battery monitoring devices 30 are aligned in a straight line along the X direction. The base-side wireless antenna 43 and each of the slave-side wireless antennas 33 are also aligned in a straight line along the X direction. Therefore, as shown by the dashed line in FIG. 4, the radio wave propagation path (or propagation path, the same applies hereinafter) 71 is the same as the straight line along which the base-side wireless antenna 43 and each of the slave-side wireless antennas 33 are aligned.

[0045] The radio wave propagation path 71 is a space connecting the master-side wireless antenna 43 of the battery control device 40 and the slave-side wireless antenna 33 of the battery monitoring device 30, and is a path through which radio waves can propagate without being blocked. For this reason, it is desirable that the width of the propagation path 71 in a direction perpendicular to the direction of propagation of the radio waves be equal to or greater than a predetermined size, for example, equal to or greater than half the wavelength λ of the radio waves, over the entire area. In other words, the propagation path 71 is arranged so that radio wave shielding objects such as conductors cross the direction of propagation of the radio waves, so as not to block the radio waves. The propagation path 71 may be curved as long as the radio waves are not blocked.

[0046] For the above reasons, in the first embodiment, a linear propagation path 71 is illustrated, but this is only one example, and in reality, there are also propagation paths (not shown) in which radio waves are reflected by the side surface in the Y direction of the storage case 50, the top surface in the Z direction, the top surface of the battery block 21, etc., and reach the battery monitoring device 30 or the battery control device 40.

[0047] 3 to 5 are merely examples of the arrangement of the battery pack 20, battery monitoring device 30, battery control device 40, and junction box 60, and may be changed as desired. Specific examples of such changes will be described later.

[0048] Incidentally, in order to ensure proper wireless communication, the battery monitoring system 100 is housed in a housing case 50 to suppress external influences such as external noise. However, even if the battery monitoring system 100 is housed in the housing case 50, depending on the arrangement and shape of the battery cells 22 and battery blocks 21 inside the housing case 50, radio wave interference may occur between the radio waves of the wireless communication and their reflected waves, resulting in a deterioration in communication quality.

[0049] The principle behind the occurrence of radio wave interference will now be described with reference to Figure 6. Figure 6 schematically illustrates a radio wave propagation path 71 in this embodiment. As shown in Figure 6, two battery blocks 21 are arranged on the bottom surface 52 of the housing case 50 with a predetermined gap 25 between them. A space is provided between the battery blocks 21 and the top surface 51 of the housing case 50, and this space serves as the radio wave propagation path 71.

[0050] That is, between the battery block 21 and the top surface 51 of the casing 50, the transmitter 1 (either the battery monitoring device 30 or the battery control device 40) is disposed on the left side in Fig. 6, and the receiver 2 (the other of the battery monitoring device 30 and the battery control device 40) is disposed on the right side. In this case, radio waves (incident waves) are emitted from the left side to the right side so as to pass between the top surface of the battery block 21 and the top surface 51 of the casing 50. In Fig. 6, these radio waves (incident waves) are indicated by solid arrows.

[0051] When radio waves are emitted from left to right, some of the radio waves enter the gaps 25 between the battery blocks 21 and branch off, as shown by the dashed arrows in Figure 6. The radio waves are then reflected off the bottom of the gaps 25 between the battery blocks 21 (bottom surface 52 of the housing case 50), return to the propagation path 71, and branch off to the left and right.

[0052] When the reflected wave branches off from the incident wave and travels back and forth in the vertical direction through gap 25, a phase shift occurs with respect to the incident wave. The phase shift occurs according to the round-trip distance from the incident wave until it returns, that is, the depth dimension d in the vertical direction of gap 25. Specifically, as shown in FIG. 7, if the wavelength of the radio wave is "λ" and n is a natural number, the phase difference approaches 0° as the depth dimension d approaches (n-1)×λ / 2, and the phase difference approaches 180° as the depth dimension d approaches (2n-1)×λ / 4.

[0053] The closer the phase difference between the reflected wave traveling to the right and the radio wave (incident wave) is to 180°, i.e., the closer they are to opposite phases, the more the radio wave is canceled out by the reflected wave and becomes weaker. As a result, as shown by the dashed line in Figure 8, the received power of the radio wave received by receiver 2 weakens, deteriorating communication quality. In Figure 8, the horizontal axis represents the frequency (Hz) of the radio wave, and the vertical axis represents the loss (dB) of the radio wave received by receiver 2 relative to the radio wave (incident wave) emitted by transmitter 1.

[0054] In Figure 6, we have explained the case where the upper side of the storage case 50 is used as the propagation path 71, but even if the side of the storage case 50, i.e., the space between the side of the battery block 21 and the side of the storage case 50, is used as the propagation path, the same phenomenon will occur if there are similar gaps 25 between the battery blocks 21.

[0055] 6 has been described using the gap 25 between battery blocks 21 as an example, the same phenomenon occurs if there is a gap between battery cells 22 on the propagation path. The same phenomenon occurs if there is a gap between the battery pack 20 and the housing case 50, a gap between the battery block 21 and the housing case 50, or a gap between the battery cell 22 and the housing case 50 on the propagation path.

[0056] Here, gaps 25 in battery block 21 that may cause radio wave interference refer to gaps that cross propagation path 71. In other words, these are gaps that do not extend along the direction of propagation of radio waves in propagation path 71, but rather gaps that increase the width of propagation path 71 in a direction perpendicular to the direction of propagation. It is also desirable that propagation path 71 be as short as possible.

[0057] From the above, the present inventors have discovered that it is desirable to have as few irregularities as possible, such as gaps 25 between battery blocks 21, along radio wave propagation path 71. Therefore, in this embodiment, a configuration is adopted as shown in Figures 3 to 5 so as to close gaps 25 between battery blocks 21. A detailed description will be given with reference to Figures 3 to 5.

[0058] As described above, the battery control device 40 and the battery monitoring device 30 are located at the same position in the Z direction and the Y direction, and are arranged in a straight line with no obstructions between them. In this case, the straight line connecting the battery control device 40 and the battery monitoring device 30 is at least the propagation path 71. In Figures 4 and 5, the propagation path 71 is illustrated by a dashed line.

[0059] The propagation path 71 is provided with a blocking plate 81 as a radio wave penetration suppression member that blocks the gaps 25 between the battery blocks 21 (more specifically, the case bodies 21a of the battery blocks 21; the same applies below) from the Z direction (from above). The blocking plate 81 is made of a conductive material such as metal and is formed in the shape of a long, narrow plate extending along the Y direction. Since the gaps 25 between the battery blocks 21 are formed to extend in the Y direction, the blocking plate 81 is also formed in the shape of a long, narrow plate extending along the gaps 25 between the battery blocks 21. The length dimension (length dimension in the Y direction) of the blocking plate 81 is the same as that of the battery blocks 21. In this embodiment, in order to block all of the gaps 25 between the battery blocks 21 in the propagation path 71, each gap 25 is blocked by a plurality of blocking plates 81.

[0060] The blocking plate 81 blocks the opening on the upper side (Z+ direction) of the gap 25 in the vertical direction so that there is no step between the top surface of the battery block 21 and the blocking plate 81, that is, so that the top surface of the battery block 21 and the blocking plate 81 are flush with each other. This prevents the formation of gaps 25 between the battery blocks 21 (gaps 25 recessed in the Z- direction) in the propagation path 71, and suppresses the occurrence of unevenness.

[0061] By closing the gaps 25 between the battery blocks 21 with the closing plates 81 in this way, radio wave interference can be prevented and the received power can be maintained in a good state, as shown by the solid line in FIG.

[0062] The effects of the first embodiment will be described below.

[0063] The gaps 25 between the battery blocks 21 (more specifically, the openings of the gaps 25 recessed in the Z-direction) are blocked by conductive blocking plates 81. This prevents a portion of the radio waves (incident waves) from branching in the Z direction, entering the gaps 25, and returning as reflected waves with a predetermined phase difference from the radio waves. Therefore, as shown by the solid line in Figure 8, radio wave interference can be suppressed, and the received power can be maintained in a good state.

[0064] The influence of reflected waves due to gaps 25 is greatest due to gaps 25 and unevenness on the propagation path 71. Therefore, the blocking plate 81 blocks at least the gaps 25 on the propagation path 71 of radio waves for wireless communication between the battery monitoring device 30 and the battery control device 40. In other words, the blocking plate 81 blocks the gaps 25 that cross the propagation path 71 extending in the X direction in the Y direction from above in the Z direction. In this embodiment, the openings of the gaps 25 between the battery blocks 21 are blocked on the upper surface sides of the battery blocks 21. This reduces unevenness on the propagation path 71, suppresses radio wave interference, and maintains good received power.

[0065] The blocking plate 81 blocks the battery block 21 so that the difference in level with the flat surface of the battery block 21 (the flat surface of the case body 21a) is within a predetermined tolerance. In this embodiment, the battery monitoring device 30 is fixed to the upper surface of the case body 21a and is disposed in contact with or facing the upper surface of the case body 21a. Therefore, the blocking plate 81 blocks the battery block 21 so that the difference in level with the upper surface, which is the opposing or contact surface of the battery monitoring device 30, is within a predetermined tolerance. Specifically, the difference in level is set to λ / 8 or less. Note that in this embodiment, there is no difference in level. This makes it possible to eliminate gaps 25 with a deep depth dimension in the Z direction (gaps 25 recessed in the Z-direction) in the propagation path 71, suppressing radio wave interference and maintaining good received power.

[0066] (Second embodiment) The configuration of the battery unit 11 of the first embodiment may be partially modified. A battery unit 11 of a second embodiment will now be described.

[0067] The arrangement of battery blocks 21 in the second embodiment is shown in FIGS. 9 and 10. As shown in FIG. 9, inside a substantially rectangular parallelepiped storage case 50, the battery blocks 21 are arranged in multiple rows in the short-side direction (Y direction) and multiple rows in the long-side direction (X direction). As shown in FIG. 9, in the second embodiment, the battery blocks 21 are arranged in eight rows (some rows are not shown) in the X direction and three rows in the Y direction. As in the first embodiment, as shown in FIG. 10, a predetermined gap 25 is formed between each battery block 21 in the X direction. Furthermore, as shown in FIG. 9, a predetermined gap 26 is also formed between each battery block 21 in the Y direction. Note that, in each battery block 21, the battery cells 22 constituting the battery block 21 are arranged so as to be stacked in the Y direction of the storage case 50, but they may also be stacked in the X direction.

[0068] As in the first embodiment, a battery monitoring device 30 is fixed at approximately the center of the top surface of each battery block 21. More specifically, the battery monitoring device 30 is fixed at the center of the top surface of the battery block 21 that is located in the middle in the Y direction. As a result, as shown in FIG. 10 , the battery monitoring devices 30 are arranged at approximately the same position (height) in the up-down direction (Z direction). Furthermore, the multiple battery monitoring devices 30 are arranged in a straight line along the X direction. Note that the slave-side wireless antennas 33 are also arranged in a straight line along the X direction.

[0069] As in the first embodiment, the battery control device 40 is disposed at approximately the same position as the battery monitoring device 30 in the Z and Y directions, i.e., approximately in the center of the housing case 50. Therefore, as shown in FIG. 9 , the battery control device 40 and the multiple battery monitoring devices 30 are aligned in a straight line along the X direction. Similarly, the master-side wireless antenna 43 and the multiple slave-side wireless antennas 33 are also aligned in a straight line along the X direction. Therefore, as in the first embodiment, the straight line connecting the battery control device 40 and the battery monitoring devices 30 forms the propagation path 71.

[0070] In the second embodiment, the blocking plates 81 are provided so as to block the gaps 25 between the battery blocks 21 in the X direction (gaps 25 recessed in the Z direction), as in the first embodiment. In the second embodiment, the blocking plates 81 are provided from one end to the other of multiple rows (three rows) of battery blocks 21 in the Y direction. In other words, the blocking plates 81 are provided across multiple rows (three rows) of battery blocks 21 in the Y direction. With this configuration, the same effects as in the first embodiment can be obtained.

[0071] (Third embodiment) The configuration of the battery unit 11 of the first embodiment may be partially modified. A battery unit 11 of a third embodiment will now be described.

[0072] The arrangement of the battery block 21, battery monitoring device 30, and battery control device 40 in the third embodiment is shown in Figures 11 and 12. As shown in Figures 11 and 12, the arrangement of the battery block 21, battery monitoring device 30, and battery control device 40 is the same as in the second embodiment, so a detailed description will be omitted.

[0073] Furthermore, in the third embodiment, the blocking plates 81 are provided so as to block the gaps 25 between the battery blocks 21 in the X direction (gaps 25 recessed in the Z-direction), as in the first embodiment. Note that in the second embodiment, the blocking plates 81 are provided from one end to the other of multiple rows (three rows) of battery blocks 21 in the Y direction. In other words, the blocking plates 81 are provided across multiple rows (three rows) of battery blocks 21 in the Y direction.

[0074] The third embodiment also includes a blocking plate 82 that blocks the predetermined gaps 26 provided between the battery blocks 21 in the Y direction. The blocking plate 82 is formed in the shape of a long, narrow plate that extends in the X direction. The length of the blocking plate 82 in the X direction is the same as the length of each battery block 21 in the X direction. This configuration provides the same effects as the first embodiment.

[0075] As mentioned above, while the linear propagation path 71 is illustrated, this is only one example, and in reality, there is also a propagation path (not shown) in which radio waves are reflected by the side surface in the Y direction of the housing case 50, the top surface in the Z direction, or the top surface of the battery block 21, and reach the battery monitoring device 30 or the battery control device 40. By closing the gap 26 in the Y direction of the battery block 21 with the blocking plate 82, unevenness is reduced even in this propagation path (not shown). This suppresses radio wave interference and maintains good received power.

[0076] (Fourth embodiment) The configuration of the battery unit 11 of the first embodiment may be partially modified. A battery unit 11 of a fourth embodiment will now be described.

[0077] First, the arrangement of the battery block 21, battery monitoring device 30, and battery control device 40 in the fourth embodiment will be described with reference to Figures 13 and 14. As shown in Figure 13, the arrangement of the battery block 21 is substantially the same as in the first embodiment. However, unlike the first embodiment, a space for accommodating the battery monitoring device 30 is provided at one end in the Y direction (the lower side in Figure 13). Furthermore, as shown in Figure 14, there is no space that could serve as a radio wave propagation path 71 between the top surface of the battery block 21 and the top surface of the housing case 50.

[0078] The battery monitoring devices 30 are fixed to the Y-direction side surfaces of each battery block 21 in the space to the side (the space between the Y-direction side surfaces of the battery blocks 21 and the inner side surfaces of the housing case 50). As shown in Fig. 14, the battery monitoring devices 30 are fixed near the center of each battery block 21 in the Z direction. As a result, the multiple battery monitoring devices 30 are aligned in a straight line along the X direction.

[0079] On the other hand, the battery control device 40 is disposed at the very end in the longitudinal direction (X direction) and at approximately the center in the lateral direction (Y direction). Also, as shown in Fig. 14, the battery control device 40 is disposed at approximately the same position (center in Fig. 14) as the battery monitoring device 30 in the Z direction (up-down direction). For this reason, as shown in Fig. 13, the radio wave propagation path 72 (indicated by the dashed line) in the fourth embodiment is bent in a substantially L-shape along the X-direction side surface and Y-direction side surface of the housing case 50.

[0080] The blocking plates 83 in the fourth embodiment are provided to block gaps 25 between battery blocks 21 in the X direction. More specifically, the blocking plates 83 block gaps 25 between battery blocks 21 from the Y direction on the side surfaces of the battery blocks 21 so as to block gaps 25 that are recessed in the Y direction and that may become uneven in the propagation path 72.

[0081] Specifically, the blocking plate 83 is formed in the shape of a long, narrow plate and is configured to extend in the Z direction from the upper end to the lower end of the battery block 21. In other words, the blocking plate 83 is provided across almost the entire width in the Z direction inside the housing case 50 (battery housing space). The blocking plate 83 then blocks the gap 25 from the Y direction on the side of the battery block 21 in the Y direction, more specifically, on the contact surface (or opposing surface) side of the battery monitoring device 30.

[0082] In this case, the blocking plate 83 blocks the opening of the gap 25 on the battery monitoring device 30 side in the Y direction so that there is no step in the Y direction between the side surface of the battery block 21 to which the battery monitoring device 30 is attached and the blocking plate 83, that is, so that the side surface of the battery block 21 and the blocking plate 83 are flush with each other. This prevents the formation of gaps 25 between the battery blocks 21 (gaps 25 recessed in the Y direction) in the propagation path 72 between the Y direction side surface of the battery block 21 and the side surface of the accommodating case 50, and suppresses the occurrence of unevenness.

[0083] The effects of the fourth embodiment will be described below.

[0084] The blocking plate 83 of the fourth embodiment blocks the gaps 25 between the battery blocks 21 (gaps 25 recessed in the Y direction) from the Y direction in the space of the propagation path 72 between the Y direction side surface of the battery block 21 and the inner side surface of the accommodating case 50. In other words, the blocking plate 83 blocks the gaps 25 between the battery blocks 21 from the battery monitoring device 30 side.

[0085] Therefore, when radio waves from the battery monitoring device 30 or the battery control device 40 pass through the space between the Y-direction side surface of the battery block 21 and the inner side surface of the housing case 50, it is possible to prevent the phase of the reflected waves from shifting due to unevenness in the Y direction caused by the gaps 25 between the battery blocks 21. This makes it possible to suppress radio wave interference and maintain good received power.

[0086] The blocking plate 83 blocks the battery so that the difference in level with the side surface of the battery block 21 to which the battery monitoring device 30 is attached is within a predetermined tolerance. More specifically, the blocking plate 83 is designed so that the difference in level with the side surface of the battery block 21 that is the contact surface or opposing surface of the battery monitoring device 30 is λ / 8 or less. This eliminates the gap 25 with a large depth dimension in the Y direction in the space of the propagation path 72 between the Y direction side surface of the battery block 21 and the inner side surface of the housing case 50, suppressing radio wave interference and maintaining good received power.

[0087] (Fifth embodiment) The configuration of the battery unit 11 of the first embodiment may be partially modified. A battery unit 11 of the fifth embodiment will be described below.

[0088] First, the arrangement of the battery block 21, battery monitoring device 30, and battery control device 40 in the fifth embodiment will be described with reference to Figures 15 to 17. As shown in Figure 15, the arrangement of the battery block 21 is substantially the same as in the first embodiment. However, unlike the first embodiment, a space for accommodating the battery monitoring device 30 is provided at one end in the Y direction (the lower side in Figure 15). As shown in Figures 16 and 17, similar to the first embodiment, a space that can serve as a propagation path for radio waves is provided between the top surface of the battery block 21 and the top surface of the housing case 50.

[0089] The battery monitoring devices 30 are fixed to the Y-direction side surfaces of each battery block 21 in the space to the side (the space between the Y-direction side surface of the battery block 21 and the inner side surface of the housing case 50). As shown in Fig. 17 , the battery monitoring devices 30 are fixed near the center of each battery block 21 in the Z direction. As a result, the multiple battery monitoring devices 30 are aligned in a straight line along the X direction.

[0090] On the other hand, the battery control device 40 is disposed at the very end in the longitudinal direction (X direction) and at approximately the center in the lateral direction (Y direction). Furthermore, as shown in Fig. 17, the battery control device 40 is disposed at approximately the same position (the center in Fig. 17) as the battery monitoring device 30 in the Z direction (up-down direction). Therefore, as shown in Fig. 15, a radio wave propagation path 72 (indicated by a dashed line) in the fifth embodiment is bent in a substantially L-shape along the X-direction side surface and the Y-direction side surface of the housing case 50. Hereinafter, in the fifth embodiment, the propagation path 72 bent in a substantially L-shape and passing through the lateral space may be simply referred to as a first propagation path 72.

[0091] As described above, a space that can serve as a propagation path for radio waves is provided between the upper surface of the battery block 21 and the upper surface of the accommodating case 50. This upper space is used to provide linear propagation paths 73 that connect each battery monitoring device 30 and the battery control device 40. More specifically, as shown in FIG. 15 , the propagation paths 73 are provided radially from the battery control device 40 to each battery monitoring device 30, passing through the space between the upper surface of the battery block 21 and the upper surface of the accommodating case 50. Hereinafter, in the fifth embodiment, the radial propagation paths 73 that pass through this upper space may be simply referred to as second propagation paths 73.

[0092] In the fifth embodiment, similarly to the first embodiment, a blocking plate 81 is provided on the upper surface side of the battery blocks 21 to block the gaps 25 between the battery blocks 21 from the Z direction (from above). The configuration of the blocking plate 81 is similar to that of the first embodiment. This prevents the formation of gaps 25 recessed in the Z direction between the battery blocks 21 in the space on the upper surfaces of the battery blocks 21 in the second propagation path 73, thereby suppressing the occurrence of unevenness.

[0093] Additionally, in the fifth embodiment, similar to the fourth embodiment, a blocking plate 83 is provided on the side surface of the battery block 21 to block the gaps 25 between the battery blocks 21 from the Y direction side. The blocking plate 83 is similar to that in the fourth embodiment. This prevents the formation of gaps 25 recessed in the Y direction between the battery blocks 21 in the space between the Y direction side surface of the battery block 21 and the side surface of the housing case 50 in the first propagation path 72, thereby suppressing the occurrence of unevenness.

[0094] The effects of the fifth embodiment will be described below.

[0095] The closing plate 83 closes the gaps 25 recessed in the Y direction between the battery blocks 21. This prevents the gaps 25 between the battery blocks 21 from creating irregularities in the space between the Y direction side surface of the battery block 21 and the side surface of the housing case 50 in the first propagation path 72. This suppresses radio wave interference in the first propagation path 72 and maintains good received power.

[0096] Additionally, the gaps 25 recessed in the Z direction between the battery blocks 21 are blocked by the blocking plate 81. This prevents the gaps 25 between the battery blocks 21 from creating irregularities in the space above the battery blocks 21 in the second propagation path 73. This suppresses radio wave interference in the second propagation path 73, and allows the received power to be maintained in good condition.

[0097] Furthermore, in the fifth embodiment, two different propagation paths 72 and 73, namely, a first propagation path 72 and a second propagation path 73, are provided. This means that even if communication on one of the propagation paths 72 and 73 is poor, the other may be good, allowing for more reliable communication.

[0098] (Sixth embodiment) The configuration of the battery unit 11 of the first embodiment may be partially modified. A battery unit 11 of a sixth embodiment will be described below.

[0099] As shown in FIGS. 18 and 19, in the sixth embodiment, the arrangement of the battery block 21, the battery monitoring device 30, and the battery control device 40 is the same as in the first embodiment.

[0100] 18 , radio wave blocking walls 91 are provided as conductive partitions on the top surface of the battery unit 11 on both sides in the Y direction of the row of battery monitoring devices 30, i.e., on both sides in the Y direction of the propagation path 71. These radio wave blocking walls 91 are provided from one end of the plurality of battery blocks 21 to the other in the X direction. The radio wave blocking walls 91 are also provided upright on the top surfaces of the battery blocks 21, extending from the top surface of the battery blocks 21 to the top surface of the housing case 50. As a result, the radio wave blocking walls 91 are provided in the space above the battery blocks 21 so as to surround the propagation path 71 on both sides in the Y direction.

[0101] The effects of the sixth embodiment will be described below.

[0102] In the space above the battery block 21, the propagation path 71 is surrounded by the radio wave blocking wall 91, the upper surface of the battery block 21, and the upper surface of the housing case 50. This prevents radio waves from diffusing outside the propagation path 71 and makes it less susceptible to external influences.

[0103] Additionally, gaps 25 between battery blocks 21 are closed from above by blocking plate 81, and the top surface 51 of housing case 50 and radio wave blocking wall 91 are formed flat with no irregularities. As a result, in the space above battery block 21, propagation path 71 is smooth, radio wave interference is effectively suppressed, and received power can be maintained at a good level.

[0104] (Seventh embodiment) The configuration of the battery unit 11 of the fifth embodiment may be partially modified. A battery unit 11 of the seventh embodiment will now be described.

[0105] As shown in FIGS. 20 to 22, in the seventh embodiment, the battery block 21, the battery monitoring device 30, and the battery control device 40 are arranged in the same manner as in the fifth embodiment.

[0106] 20 and 22, a radio wave blocking wall 92 is provided as a conductive partition to block the space (the space between the Y-direction side surface of the battery block 21 and the inner side surface of the housing case 50) in which the battery monitoring device 30 is disposed from above. The radio wave blocking wall 92 is provided from one end of the battery blocks 21 to the other in the X direction. The radio wave blocking wall 92 extends upright in the Y direction from the Y-direction side surface of the battery block 21. The radio wave blocking wall 92 is provided from the Y-direction side surface of the battery block 21 to the side surface of the housing case 50. As a result, the radio wave blocking wall 92 is provided in the space to the side of the battery block 21 to surround the first propagation path 72 from above.

[0107] The effects of the seventh embodiment will be described below.

[0108] In the space to the side of battery block 21, first propagation path 72 is surrounded by radio wave blocking wall 92, the side surface of battery block 21, the side surface of accommodating case 50, and the bottom surface of accommodating case 50. In other words, radio wave blocking wall 92 separates the space to the side of battery block 21 from the space above. This prevents radio waves from diffusing outside first propagation path 72 and makes it less susceptible to influence from the space above.

[0109] Additionally, the gaps 25 between the battery blocks 21 are closed from the Y direction by a blocking plate 82, and the sides and bottom of the housing case 50 and the radio wave blocking wall 92 are formed flat and without any irregularities. As a result, in the space to the side of the battery blocks 21, the first propagation path 72 is flat and without any irregularities, which effectively suppresses radio wave interference and maintains good received power.

[0110] (Variation) A modified example in which the configuration of the battery unit 11 of each of the above embodiments is partially changed will be described below.

[0111] In each of the above embodiments, the step between the closure plates 81-83 and the flat surface (side surface or top surface) of the battery block 21 does not have to be λ / 8 or less. That is, as explained in the first embodiment with reference to FIG. 7 , it is known that the closer the depth dimension d of the gap 25 is to (n-1)×λ / 2, the closer the phase difference is to 0°, and the closer the depth dimension d is to (2n-1)×λ / 4, the closer the phase difference is to 180°. Therefore, if the step between the closure plates 81-83 and the flat surface of the battery block 21 cannot be set to λ / 8 or less, the step should be set to a value other than at least (2n-1)×λ / 4, and more preferably, to a value as close as possible to the value of (n-1)×λ / 2.

[0112] In each of the above embodiments, the blocking plates 81-83 may protrude from the flat surface (side surface or top surface) of the battery block 21. In this case, it is desirable that the difference in level between the blocking plates 81-83 and the flat surface (side surface or top surface) of the battery block 21 is within a predetermined tolerance range (for example, λ / 8 or less). If it is within the predetermined tolerance range, the effects of radio wave reflection by the protruding parts can be suppressed.

[0113] In the above embodiments, closing plates 81 to 83 are provided to close the gaps 25, 26 between the battery blocks 21. However, if gaps are formed between the battery cells 22, it is desirable to provide closing plates to close the gaps. In this case, the battery cells 22 are housed in a conductive battery case. The step between the closing plates that close the gaps between the battery cells 22 and the flat surface of the battery cells 22 is the same as in the case of the battery block 21. In this case, the battery cells 22 become the battery section.

[0114] A blocking plate may also be provided in the same manner when a gap is provided between the battery cell 22 and the battery block 21. In this case, the battery cell 22 and the battery block 21 form a battery section.

[0115] In each of the above embodiments, the case body 21a of the battery block 21 and the blocking plates 81-83 may be integrated. That is, a flange portion protruding outward from the outer edge of the case body 21a of the battery block 21 may be provided, and this flange portion may serve as a radio wave intrusion suppression member that blocks the gaps 25, 26 between the battery blocks 21. Similarly, instead of the blocking plates 81-83, a flange portion may be provided on the battery case of the battery cell 22, and used as a radio wave intrusion suppression member that blocks the gaps between the battery cells 22. This eliminates the need to separately provide and attach the blocking plates 81-83.

[0116] In each of the above embodiments, a conductive cover may be provided to cover the top or side surfaces of all the battery blocks 21 to close any gaps.

[0117] In each of the above embodiments, a blocking plate may be provided to block the gap between the battery control device 40 and the battery unit (battery assembly 20, battery block 21, or battery cell 22; hereinafter, the same applies). For example, in the first embodiment, a gap recessed in the Z direction is formed between the battery control device 40 and the battery unit in the propagation path 71. Therefore, a blocking plate may be provided to block this gap from above (Z direction).

[0118] In each of the above embodiments, a radio wave intrusion suppressing member may be provided that protrudes from the side or top surface of the casing 50 and blocks at least a part of the gap between the battery unit and the casing 50 .

[0119] In the above embodiments, plate-shaped blocking plates 81-83 are provided, but their shapes may be changed as desired. For example, radio wave penetration suppressing members may be provided to fill the entire gaps 25, 26. By configuring the radio wave penetration suppressing members in a plate shape, like the blocking plates 81-83, expansion of the battery block 21 or battery cell 22 is permitted without being impeded by the radio wave penetration suppressing members, and immediate rupture can be prevented.

[0120] Furthermore, for example, the radio wave intrusion suppressing member may be formed of an elongated member having a triangular or convex cross section. In this case, it is desirable that the apex of the triangular radio wave intrusion suppressing member or the convex portion of the convex radio wave intrusion suppressing member be inserted into the gap.

[0121] In each of the above embodiments, the wavelength λ of the radio waves used for communication may be variable. In this case, the wavelength λ used to set the step between a radio wave penetration suppression member such as closure plates 81-83 and the flat surface of a battery unit such as battery block 21 is preferably the shortest wavelength of the radio waves used.

[0122] In each of the above embodiments, the closure plates 81-83 may have a small gap (margin) to allow for expansion of the battery block 21 or battery cell 22. For example, as shown in FIG. 23 , a gap serving as an expansion margin 81a may be provided in the X-direction center of the closure plate 81, which closes the gap 25 of the battery block 21 from above, and extending along the Y direction across the entire width of the closure plate 81. Note that the direction of the expansion margin 81a does not have to be the same as the arrangement direction of the battery blocks 21 (X direction in FIG. 23 ), nor does it have to be perpendicular (Y direction in FIG. 23 ). Furthermore, as shown in FIG. 24 , the width dimension d1 of the expansion margin 81a is preferably as small as possible, and if possible, is preferably 0.03 times the wavelength λ or less. This allows for expansion of the battery block 21 or battery cell 22 while suppressing radio wave interference.

[0123] In each of the above embodiments, the closure plates 81-83 may be made of punched metal with multiple through holes. The closure plates 81-83 may also be configured in a mesh pattern. For example, as in the closure plate 81 shown in Figures 25 and 26, multiple through holes 81b, 81c may be formed aligned at a predetermined interval. The radius of these through holes 81b, 81c is preferably ¼ or less of the wavelength λ. If the radius of the through holes 81b, 81c is ¼ or less of the wavelength λ, radio waves and reflected waves can pass through the through holes 81b, 81c, preventing radio wave interference. Providing multiple through holes 81b, 81c in the closure plates 81-83 in this way allows for a reduction in the weight of the closure plates 81-83. Furthermore, expansion of the battery block 21 or battery cells 22 can be tolerated.

[0124] In each of the above embodiments, the closure plates 81 to 83 are not limited to metal and may be made of a conductive material. For example, the closure plates 81 to 83 may be made of a resin material containing carbon fiber (e.g., carbon fiber reinforced plastic (CFRP)).

[0125] In each of the above embodiments, the number and arrangement of the battery monitoring devices 30 may be changed as desired. Similarly, the number and arrangement of the battery control devices 40 may be changed as desired. Similarly, the number and arrangement of the battery blocks 21 and battery cells 22 may be changed as desired. In conjunction with these changes, the radio wave propagation paths 71-73 may also be changed as desired. Note that the radio wave propagation path is a continuous space (a space not obstructed by conductive members, etc.) connecting the battery control devices 40 and the battery monitoring devices 30, and it is desirable that the width dimension of the space in a direction perpendicular to the direction of propagation of the radio waves (width direction or vertical direction) is equal to or greater than half the wavelength λ of the radio waves throughout the entire area. As long as these conditions are met, the path may be curved or L-shaped.

[0126] Modified examples of the arrangement of each component are described below. For example, as shown in the plan view of Fig. 27, a battery monitoring device 30 may be installed on both sides of each battery block 21 in the Y direction. In this case, approximately L-shaped propagation paths 72a, 72b are formed using the lateral spaces on both sides of the battery block 21 in the Y direction. Closure plates 83a, 83b are provided in the gaps 25 between the battery blocks 21 so that the openings are closed from both sides in the Y direction.

[0127] Furthermore, when using the space above the battery block 21 to form a radial propagation path 74 from the battery control device 40 toward each battery monitoring device 30, it is desirable to block the gap 25 from above with a blocking plate 81, as in the fifth embodiment.

[0128] 28, multiple battery blocks 21 may be arranged with a predetermined gap 27 in the Y direction. The battery control device 40 may be arranged at one end in the X direction (one side space in the X direction of the battery block 21), and the battery monitoring device 30 may be arranged at the other end (the other side space in the X direction of the battery block 21). Although the battery control device 40 is fixed to the X-direction side surface of the battery block 21 in FIG. 28, the battery control device 40 may be arranged in any manner in the other side space. In this case, a radial propagation path 75 is formed from the battery control device 40 to each battery monitoring device 30, using the space above the battery blocks 21. For this reason, a blocking plate 85 is provided in the gaps 27 between the battery blocks 21 so that the opening is blocked from above (Z direction).

[0129] 29, multiple battery blocks 21 may be arranged with gaps 25, 26 in the X and Y directions, respectively. A battery monitoring device 30 may be attached to each gap 25 between the battery blocks 21 in the X direction. In this case, radio waves pass through the space above the battery blocks 21, and as shown in FIG. 29, a propagation path 76 is formed radially from the battery control device 40 to each battery monitoring device 30. Therefore, a blocking plate 86 is provided in the gap 25 between the battery blocks 21 so as to block the inside in the Y direction of each battery monitoring device 30. In other words, the blocking plate 86 prevents the battery monitoring device 30 from being blocked above it. Furthermore, the gap 26 between the battery blocks 21 in the Y direction (the central gap 26) is also blocked by a blocking plate 87.

[0130] 30, multiple battery blocks 21 may be arranged with a predetermined gap in the X direction and stacked in the Z direction (vertical direction) at the X direction end. Note that the side surface of the housing case 50 of the battery unit 11 shown in FIG. 30 is not shown. Each battery monitoring device 30 is fixed to the upper side of the battery block 21. Furthermore, the battery control device 40 is fixed to the lower side of the battery block 21 placed at the X direction end and above in the Z direction. In this case, a blocking plate 88 is attached so as to block the gap 25 between the battery blocks 21 from the Y direction.

[0131] 31, the battery blocks 21 may be arranged in two rows in the X direction, and the battery blocks 21 may be aligned in the Y direction at the end of the X direction. A battery monitoring device 30 is fixed to the side of each of the battery blocks 21 on the central aisle side of the two rows arranged in the X direction. A battery monitoring device 30 is fixed to the inner side surface (left side surface in FIG. 31) of each of the battery blocks 21 in one row arranged in the Y direction. A battery control device 40 is attached to the Y direction end (bottom in FIG. 31) of the battery blocks 21 in one row arranged in the Y direction.

[0132] In this case, the central passage between the two rows of battery blocks 21 arranged in the X direction becomes propagation paths 78a and 78b, and the passage between the two rows of battery blocks 21 arranged in the X direction and the one row of battery blocks 21 arranged in the Y direction becomes propagation path 78c.

[0133] Therefore, gaps 28 between battery blocks 21 arranged in the X direction are blocked by blocking plate 89a from the inside in the Y direction. Also, gaps 29 between battery blocks 21 arranged in the Y direction are blocked by blocking plate 89b from the inside in the X direction. Note that if the space above battery blocks 21 is used as a propagation path, it is desirable to also block the gaps between battery blocks 21 from above.

[0134] In the above embodiment, the shape of the storage case 50 may be changed as desired. In the above embodiment and each modified example, the closure plates 81, 82, 83, 83a, 83b, 85, 86, 87, 88, 89a, 89b, 89c may be configured to close at least a portion of the gap between the battery unit and the housing and the gap between the battery units. In other words, they do not need to be exactly the same as the width of the gap to completely close it, and may be shorter than the width. Similarly, they do not need to be exactly the same as the length of the gap to completely close it, and may be shorter than the length. Similarly, they do not need to be exactly the same as the depth of the gap to completely close it, and may be thinner than the depth. In the above embodiment and each of the modified examples, one radio wave intrusion suppression member may be used to block all gaps within the casing 50 (gaps between the battery unit and the housing and gaps between the battery units).

[0135] In each of the above embodiments, a conductive cross beam for the battery block 21 may be provided in addition to the closure plates 81 to 83. In the above-described embodiments and modifications, the blocking plates 81, 82, 83, 83a, 83b, 85, 86, 87, 88, 89a, 89b, and 89c do not have to be made of a conductive material as long as they are made of a material that can suppress the penetration of radio waves.

[0136] The following describes technical ideas that can be derived from the above-described embodiment and modifications.

[0137] [Configuration 1] A battery unit (11) including battery sections (20, 21, 22), a battery monitoring device (30) that detects battery information and transmits it by wireless communication, a battery control device (40) that receives the battery information from the battery monitoring device by wireless communication, and a conductive housing (50) that houses them, One or more battery units are housed inside the housing, The battery unit includes a radio wave intrusion suppression member (81, 82, 83, 83a, 83b, 85, 86, 87, 88, 89a, 89b, 89c) that blocks at least a portion of the gap between the battery unit and the housing and the gaps (25, 26, 27, 28, 29) between the battery units.

[0138] [Configuration 2] The battery unit according to configuration 1, wherein the radio wave intrusion suppression member blocks at least a part of the gap on a radio wave propagation path (71, 72, 72a, 72b, 73, 74, 75, 76, 78a, 78b, 78c) of wireless communication between the battery monitoring device and the battery control device.

[0139] [Configuration 3] The battery unit is housed in a battery case, 3. The battery unit according to claim 1, wherein the radio wave penetration suppression member is provided so that a difference in level between the radio wave penetration suppression member and a flat surface of the battery case falls within a predetermined tolerance range.

[0140] [Configuration 4] one of the battery monitoring device and the battery control device is disposed facing or in contact with one surface of the battery case, The battery unit according to any one of configurations 1 to 3, wherein the radio wave penetration suppressing member is provided so that a step between the opposing surface or contact surface of the battery case falls within a predetermined tolerance range.

[0141] [Configuration 5] When the wavelength of the radio wave is λ and n is a natural number, 5. The battery unit according to configuration 4, wherein the step of the radio wave penetration suppression member relative to the surface facing or in contact with the battery case is λ / 8 or less.

[0142] [Configuration 6] When the wavelength of the radio wave is λ and n is a natural number, 5. The battery unit according to configuration 4, wherein the step of the radio wave penetration suppression member relative to the opposing surface or contact surface of the battery case is a value other than (2n-1)×λ / 4.

[0143] [Configuration 7] When the wavelength of the radio wave is λ and n is a natural number, 5. The battery unit according to configuration 4, wherein the step of the radio wave penetration suppressing member relative to the surface facing or in contact with the battery case is set to a value of (n-1)×λ / 2.

[0144] [Configuration 8] 8. The battery unit according to any one of configurations 1 to 7, wherein the radio wave penetration suppression member has a gap formed therein to provide room for the battery section to expand.

[0145] [Configuration 9] 9. The battery unit according to any one of configurations 1 to 8, wherein the radio wave penetration suppressing member is formed in a mesh shape or made of punched metal.

[0146] [Configuration 10] a partition (91, 92) formed in a long plate shape along a propagation path of radio waves for wireless communication between the battery monitoring device and the battery control device; The battery unit according to any one of configurations 1 to 9, wherein the partition separates the propagation path from other areas. [Explanation of symbols]

[0147] 11...battery unit, 20...battery pack, 21...battery block, 21a...case body, 22...battery cell, 25, 26, 27, 28, 29...gap, 30...battery monitoring device, 33...sub-unit wireless antenna, 40...battery control device, 43...base unit wireless antenna, 50...storage case, 71, 72, 72a, 72b, 73, 74, 75, 76, 78a, 78b, 78c...propagation path, 81, 82, 83, 83a, 83b, 85, 86, 87, 88, 89a, 89b, 89c...blocking plate, 91, 92...radio wave blocking wall, 100...battery monitoring system.

Claims

1. A battery unit (11) including a battery section (20, 21, 22), a battery monitoring device (30) that detects battery information and transmits it by wireless communication, a battery control device (40) that receives the battery information from the battery monitoring device by wireless communication, and a conductive housing (50) that houses them, One or more battery units are housed inside the housing, A battery unit including a radio wave intrusion suppression member (81, 82, 83, 83a, 83b, 85, 86, 87, 88, 89a, 89b, 89c) that blocks at least a portion of the gap between the battery unit and the housing and the gaps between the battery units (25, 26, 27, 28, 29).

2. 2. The battery unit according to claim 1, wherein the radio wave intrusion suppression member blocks at least a portion of the gap on a radio wave propagation path (71, 72, 72a, 72b, 73, 74, 75, 76, 78a, 78b, 78c) of wireless communication between the battery monitoring device and the battery control device.

3. The battery unit is housed in a battery case, The battery unit according to claim 2 , wherein the radio wave penetration suppressing member is provided so that a difference in level between the radio wave penetration suppressing member and a flat surface of the battery case is within a predetermined tolerance range.

4. one of the battery monitoring device and the battery control device is disposed facing or in contact with one surface of the battery case, The battery unit according to claim 3 , wherein the radio wave penetration suppression member is provided so that a step between the opposing surface or the contact surface of the battery case falls within a predetermined tolerance range.

5. When the wavelength of the radio wave is λ and n is a natural number, 5. The battery unit according to claim 4, wherein a step of the radio wave penetration suppression member relative to a surface facing or in contact with the battery case is λ / 8 or less.

6. When the wavelength of the radio wave is λ and n is a natural number, 5. The battery unit according to claim 4, wherein a step of the radio wave penetration suppression member relative to the opposing surface or contact surface of the battery case is set to a value other than (2n-1)×λ / 4.

7. When the wavelength of the radio wave is λ and n is a natural number, 5. The battery unit according to claim 4, wherein the step of the radio wave penetration suppression member relative to the surface facing or contacting the battery case is set to a value of (n-1) x λ / 2.

8. 8. The battery unit according to claim 1, wherein the radio wave penetration suppression member has a gap formed therein to provide room for expansion of the battery portion.

9. 8. The battery unit according to claim 1, wherein the radio wave penetration suppressing member is formed in a mesh shape or made of punched metal.

10. a partition (91, 92) formed in a long plate shape along a propagation path of radio waves for wireless communication between the battery monitoring device and the battery control device; The battery unit according to any one of claims 1 to 7, wherein the partition separates the propagation path from other areas.

Images