Voltage detection device and battery management system

Abstract

To make it possible to reduce power consumption due to communication in a battery management system in which a voltage detection device and a management device communicate with each other.SOLUTION: A voltage detection device 2 is connected to a battery module to detect the voltage of the battery module, and includes a voltage acquisition unit 2b that acquires voltage data of the battery module, a data generation unit 2e that is capable of compressing the voltage data acquired by the voltage acquisition unit 2b and generates transmission data including the voltage data, and a transmission unit 2g that transmits the transmission data generated by the data generation unit 2e. The data generation unit 2e changes a compression rate of the voltage data based on a charging rate of the battery module.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a voltage detection device and a battery management system. [Background technology]

[0002] For example, Patent Document 1 describes a method for compressing communication data to shorten the communication data, thereby reducing power consumption in a wireless communication device. Such a wireless communication device disclosed in Patent Document 1 is used for wide-area wireless communication including wireless communication at base stations, relay stations, etc. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2012-129805 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, a battery management system for managing a battery module is mounted on an electric vehicle such as an electric vehicle or a hybrid vehicle. Such a battery management system includes a voltage detection device for detecting the voltage of the battery module, and a management device for managing the battery module based on the detection result of the voltage detection device. The voltage detection device is provided for each of the battery modules. These voltage detection devices and management devices are housed inside a housing case. In recent years, a proposal has been made to wirelessly communicate between these multiple voltage detection devices and the management device. These voltage detection devices and management devices operate with power stored in the battery modules. For this reason, in order to improve the power consumption of an electric vehicle, it is necessary to suppress the power consumption of the voltage detection devices and management devices. However, in a battery management system that performs wireless communication at an extremely short distance, there has been no proposal to suppress power consumption by compressing communication data as disclosed in Patent Document 1.

[0005] The present invention has been made in consideration of the above-mentioned problems, and has an object to make it possible to reduce power consumption due to communication in a battery management system in which a voltage detection device and a management device communicate with each other. [Means for solving the problem]

[0006] The present invention employs the following configuration as a means for solving the above problems.

[0007] A first aspect of the present invention is a voltage detection device connected to a battery module to detect the voltage of the battery module, comprising a voltage acquisition unit that acquires voltage data of the battery module, a data generation unit that is capable of compressing the voltage data acquired by the voltage acquisition unit and generates transmission data including the voltage data, and a transmission unit that transmits the transmission data generated by the data generation unit, and adopts a configuration in which the data generation unit changes the compression rate of the voltage data based on the charging rate of the battery module.

[0008] A second aspect of the present invention is a battery management system comprising a voltage detection device that detects the voltage of a battery module mounted on a vehicle, and a management device that is capable of communicating with the voltage detection device and manages the battery module based on transmission data input from the voltage detection device, wherein the voltage detection device is the voltage detection device of the first aspect of the present invention. Effect of the Invention

[0009] According to the present invention, the compression rate of the voltage data is changed based on the charging rate of the battery module. When the data is compressed, the data accuracy may be deteriorated. However, the voltage data does not necessarily need to be highly accurate at all times depending on the charging rate of the battery module. Therefore, by compressing the voltage data according to the charging rate of the battery module, the volume of the transmitted data can be reduced compared to the case where the voltage data is not compressed. Therefore, according to the present invention, in a battery management system in which a voltage detection device and a management device communicate with each other, it is possible to suppress power consumption due to communication. [Brief description of the drawings]

[0010] [Figure 1] 1 is a block diagram showing a schematic configuration of a battery management system according to an embodiment of the present invention; [Diagram 2] 2 is a block diagram showing a part of a functional configuration of a voltage detection device provided in the battery management system according to an embodiment of the present invention. FIG. [Diagram 3] 4 is a schematic diagram showing a data format of transmission data generated by a voltage detection device included in the battery management system according to the embodiment of the present invention; FIG. [Figure 4] 2 is a block diagram showing a part of a functional configuration of a management device provided in the battery management system according to an embodiment of the present invention. FIG. [Diagram 5] 1 is a graph showing the relationship between the charging rate of a battery module and the compression rate of voltage data. [Figure 6] 4 is a flowchart for explaining an operation of a management device provided in the battery management system according to an embodiment of the present invention. [Figure 7] 4 is a flowchart for explaining an operation of a voltage detection device provided in the battery management system according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a voltage detection device and a battery management system according to the present invention will be described with reference to the drawings.

[0012] 1 is a block diagram showing a schematic configuration of a battery management system 1 according to the present embodiment. For example, an electrically powered vehicle such as an electric vehicle or a hybrid vehicle is equipped with a battery pack that houses a plurality of battery modules M. The battery management system 1 according to the present embodiment is provided in such a battery pack, and is housed in a housing case together with the battery modules M to manage the plurality of battery modules M.

[0013] Each battery module M includes a plurality of battery cells connected in series. The battery module M is a secondary battery that supplies DC power to an external load with an output voltage (battery voltage) that is the sum of the electromotive voltages of the plurality of battery cells. Such a battery module M is, for example, a lithium ion battery. These battery modules M are connected in series.

[0014] 1, the battery management system 1 of the present embodiment includes a plurality of voltage detection devices 2 and a single management device 3. The battery management system 1 of the present embodiment manages the battery modules M as described above. For example, the management of the battery modules M includes monitoring the total voltage of the battery modules M and the voltage of each battery cell (cell voltage).

[0015] Furthermore, the management of the battery module M may include an equalization process for equalizing the voltages of the individual battery cells. The management of the battery module M may also include changing the connection state of the battery module M with an external device (e.g., a power conversion device). For example, the battery management system 1 changes the connection state of the battery module M with the external device by controlling a contactor provided between the battery module M and the external device.

[0016] The voltage detection device 2 is provided for each battery module M, detects the voltage of the battery module M, and outputs the detection result. Each voltage detection device 2 is capable of detecting the voltage (cell voltage) of each of the multiple battery cells included in the battery module M.

[0017] Each voltage detection device 2 includes, for example, a semiconductor integrated circuit and a memory mounted on a board, and functions when these hardware components operate based on a predetermined program. Such a voltage detection device 2 includes, for example, a discharge circuit for discharging each of the battery cells. The voltage detection device 2 can equalize the cell voltages using these discharge circuits under the control of the management device 3.

[0018] 1, in this embodiment, each voltage detection device 2 includes a wireless communication antenna 2a. The wireless communication antenna 2a is an antenna for wireless communication with the management device 3. That is, in this embodiment, each voltage detection device 2 is connected to the management device 3 inside the storage case of the battery pack so as to be able to wirelessly communicate with each other.

[0019] 2 is a block diagram showing a part of the functional configuration of the voltage detection device 2. As shown in this figure, the voltage detection device 2 has, as functional units, a voltage acquisition unit 2b, a diagnosis unit 2c, a control instruction unit 2d, a data generation unit 2e, a receiving unit 2f, and a transmitting unit 2g.

[0020] The voltage acquisition unit 2b acquires voltage data of the battery module M based on the voltage value input from the battery module M. The voltage data here includes, for example, a total voltage value of the battery module M and cell voltage values ​​which are voltage values ​​of each battery cell. The voltage acquisition unit 2b outputs the voltage data acquired in this manner. In addition, such voltage data is compressible data which can be lossy compressed. In this embodiment, the voltage data is lossy compressed by the data generation unit 2e.

[0021] The diagnostic unit 2c performs self-diagnosis of the voltage detection device 2. The diagnostic unit 2c outputs the result of the self-diagnosis of the voltage detection device 2 as diagnostic information. The control instruction unit 2d generates and outputs control information to be transmitted from the voltage detection device 2 to the management device 3. The diagnostic information output from the diagnostic unit 2c and the control information output from the control instruction unit 2d are data that require high accuracy (hereinafter referred to as high accuracy data) and are different from voltage data. In this embodiment, the diagnostic information and control information are losslessly compressed by the data generation unit 2e. Furthermore, the diagnostic information and control information may be incorporated into the transmission data without being compressed by the data generation unit 2e.

[0022] The data generating unit 2e generates transmission data to be transmitted to the management device 3 via the transmitting unit 2g. Fig. 3 is a schematic diagram showing a data format of the transmission data. As shown in this figure, the data generating unit 2e generates the transmission data including a high-precision data section, a compression method data section, and a compressible data section.

[0023] The data generating unit 2e generates a compressible data portion from the voltage data acquired by the voltage acquiring unit 2b. That is, the compressible data portion is generated by compressing the compressible data. The compression rate of the voltage data is set by the management device 3 based on the charging rate of the battery module M. The compression rate set by the management device 3 is input to the voltage detection device 2, and the data generating unit 2e compresses the voltage data at the compression rate set by the management device 3. Note that the compressible data portion may include compressible data different from the voltage data.

[0024] The data generating unit 2e generates a high-precision data section from the diagnostic information generated by the diagnostic unit 2c and the control information generated by the control instruction unit 2d. The data generating unit 2e may generate the high-precision data section without compressing the high-precision data, for example. The data generating unit 2e may generate the high-precision data section by losslessly compressing the high-precision data.

[0025] The compressed data method section includes a compression ratio of the voltage data, a compression method of the voltage data, etc. For example, the voltage data can be compressed based on the MP3 method or the MP4 method. The compressed data method section includes information indicating the method by which the voltage data is compressed.

[0026] In addition, the compression data method section includes information indicating the method by which the high-precision data is compressed when the high-precision data is losslessly compressed. For example, the high-precision data can be compressed based on a lossless audio method. In addition, in the case where the high-precision data is not compressed, the compression data method section includes information indicating that the high-precision data is not compressed.

[0027] Returning to Fig. 2, the receiver 2f receives the transmission data transmitted from the management device 3 via the wireless communication antenna 2a. The transmission data transmitted from the management device 3 includes information indicating, for example, the compression rate of the voltage data. Therefore, the receiver 2f extracts the information indicating the compression rate of the voltage data from the transmission data transmitted from the management device 3 and inputs it to the data generator 2e. The transmitter 2g transmits the transmission data generated by the data generator 2e to the management device 3 via the wireless communication antenna 2a.

[0028] The management device 3 judges the state of the battery modules M based on the detection results input from each voltage detection device 2, and manages each battery module M based on the judgment result. In other words, the management device 3 is capable of wireless communication with the voltage detection devices 2, and manages the battery modules M based on the detection results of the voltage detection devices 2. The management device 3 includes, for example, a one-chip microcomputer mounted on a board, and functions when such hardware operates based on a predetermined program. As shown in FIG. 1, the management device 3 includes a wireless communication antenna 3a. The wireless communication antenna 3a of the management device 3 is an antenna for wireless communication with each voltage detection device 2.

[0029] 4 is a block diagram showing a part of the functional configuration of the management device 3. As shown in this figure, the management device 3 has, as functional units, a charging rate calculation unit 3b, a compression rate setting unit 3c, a receiving unit 3d, and a transmitting unit 3e.

[0030] The charging rate calculation unit 3b calculates the charging rate (eg, SOC: State Of Charge) of the battery module M to which each voltage detection device 2 is connected, based on the voltage data included in the transmission data transmitted from each voltage detection device 2.

[0031] For example, a charge end voltage and a discharge end voltage are set for each battery module M. The charge end voltage indicates the voltage when the battery module M is fully charged, and indicates the upper limit voltage during charging. In other words, the charge rate of the battery module M at the charge end voltage is 100%. The discharge end voltage indicates the voltage when the battery module M is completely discharged, and indicates the lower limit voltage during discharging. In other words, the charge rate of the battery module M at the discharge end voltage is 0%.

[0032] For example, the charging rate calculation unit 3b calculates the charging rate of the battery module M by comparing the voltage data included in the transmission data of the voltage detection device 2 with at least one of the charging end voltage and the discharging end voltage.

[0033] The compression rate setting unit 3c sets the compression rate of the voltage data in each voltage detection device 2 based on the charging rate of the battery module M calculated by the charging rate calculation unit 3b. Fig. 5 is a graph showing the relationship between the charging rate of the battery module M and the compression rate of the voltage data. As shown in Fig. 5, the fluctuation range of the charging rate (the range of charging rates from 0% to 100%) has a high charging rate range including a charging rate (100%) indicating that the voltage of the battery module M is a charging end voltage, a low charging rate range including a charging rate (0%) indicating that the voltage of the battery module M is a discharging end voltage, and an intermediate charging rate range between the high charging rate range and the low charging rate range.

[0034] In this embodiment, as shown in Fig. 5, the compression rate setting unit 3c sets the compression rate of the voltage data in the high charging rate range and the low charging rate range lower than that in the intermediate charging rate range. The compression rate set by the compression rate setting unit 3c is transmitted to the voltage detection device 2. In the voltage detection device 2, the data generation unit 2e compresses the voltage data based on the compression rate set by the compression rate setting unit 3c, as described above. That is, in this embodiment, the data generation unit 2e changes the compression rate of the voltage data based on the charging rate of the battery module M.

[0035] Also, as shown in Fig. 5, the compression rate setting unit 3c sets the compression rate in the high charging rate range to be lower as the charging rate becomes higher. Also, the compression rate setting unit 3c sets the compression rate in the low charging rate range to be lower as the charging rate becomes lower. That is, in this embodiment, the data generating unit 2e lowers the compression rate in the high charging rate range as the charging rate becomes higher, and lowers the compression rate in the low charging rate range as the charging rate becomes lower. However, the compression rate in the high charging rate range may be constant. Also, the compression rate in the low charging rate range may be constant.

[0036] In lossy data compression, as the compression rate increases, more data is discarded and the accuracy of the data decreases. When the voltage of the battery module M is close to the end-of-charge voltage and the end-of-discharge voltage, if the accuracy of the voltage data is low, it is difficult to use the battery module M up to the end-of-charge voltage and the end-of-discharge voltage. This is because, if the accuracy of the voltage data is low, charging and discharging must be stopped well before the end-of-charge voltage and the end-of-discharge voltage are reached, taking into account the error contained in the voltage data.

[0037] For this reason, in this embodiment, the compression rate of the voltage data is lowered in a high charging rate range including a charging rate (100%) indicating that the voltage of the battery module M is the charging end voltage, and in a low charging rate range including a charging rate (0%) indicating that the voltage of the battery module M is the discharging end voltage. This improves the accuracy of the voltage data in the high charging rate range and the low charging rate range, thereby expanding the range of use of the battery module M.

[0038] On the other hand, in the intermediate charging rate range, highly accurate voltage data is not required. For this reason, in this embodiment, the compression rate of the voltage data is increased in the intermediate charging rate range. By increasing the compression rate of the voltage data in this way, the data volume of the transmission data transmitted from each voltage detection device 2 can be reduced, and the power required for transmitting the transmission data can be reduced. Therefore, the power consumption due to communication in the voltage detection device 2 can be suppressed. Similarly, the data volume received by the management device 3 can be reduced, and the power consumption due to communication in the management device 3 can be suppressed.

[0039] Returning to Fig. 4, the receiver 3d receives the transmission data transmitted from each voltage detection device 2 via the wireless communication antenna 3a. The transmission data transmitted from the voltage detection device 2 includes information indicating, for example, voltage data. Therefore, the receiver 3d extracts the information indicating the voltage data from the transmission data and inputs it to the charging rate calculation unit 3b. The transmitter 3e transmits the transmission data including the compression ratio set by the compression ratio setting unit 3c to the voltage detection device 2 via the wireless communication antenna 3a.

[0040] Next, the operation of the battery management system 1 of the present embodiment will be described with reference to the flowcharts of FIGS.

[0041] 6 is a flowchart for explaining the operation of the management device 3. As shown in this figure, the management device 3 calculates the charging rate of each battery module M (step S11). Here, the charging rate calculation unit 3b calculates the charging rate based on the voltage data acquired by the voltage detection device 2 (voltage data included in the transmission data).

[0042] Next, the management device 3 judges whether the charging rate is within the range requiring high accuracy (step S12). In this embodiment, the range requiring high accuracy is the high charging rate range and the low charging rate range. Here, the compression rate setting unit 3c of the management device 3 judges that the charging rate is within the range requiring high accuracy when the charging rate calculated by the charging rate calculation unit 3b is within the high charging rate range and the low charging rate range. On the other hand, the compression rate setting unit 3c of the management device 3 judges that the charging rate is not within the range requiring high accuracy when the charging rate calculated by the charging rate calculation unit 3b is within the intermediate charging rate range.

[0043] If it is determined in step S12 that the charging rate is within the range requiring high accuracy, the management device 3 determines a compression rate (step S13). Here, the compression rate setting unit 3c of the management device 3 determines a compression rate that is lower than the compression rate when the charging rate is within the intermediate charging rate range. On the other hand, if it is determined in step S12 that the charging rate is not within the range requiring high accuracy, the management device 3 sets the compression rate to a high compression rate (step S14). The high compression rate is the compression rate in the intermediate charging rate range, and is set to a constant value higher than the charging rate when it is within the high charging rate range and the low charging rate range.

[0044] Once the compression rate is set in step S13 or step S14, the management device 3 transmits the set compression rate to the voltage detection device 2 (step S15). The compression rate is set for each voltage detection device 2. For example, only the compression rate for that voltage detection device 2 is transmitted to each voltage detection device 2, and compression rates for the other voltage detection devices 2 are not transmitted. Here, the transmitter 3e of the management device 3 transmits transmission data including information indicating the compression rate to the voltage detection device 2.

[0045] 7 is a flowchart for explaining the operation of each voltage detecting device 2. As shown in this figure, the voltage detecting device 2 receives the compression ratio set by the management device 3 (step S21). Here, each voltage detecting device 2 receives the compression ratio transmitted from the management device 3 at the receiving unit 2f.

[0046] Next, each voltage detection device 2 creates transmission data (step S22). Here, each voltage detection device 2 generates the transmission data in the data generation unit 2e from the voltage data acquired by the voltage acquisition unit 2b, the diagnostic information generated by the diagnosis unit 2c, and the control information created by the control instruction unit 2d. In this embodiment, each voltage detection device 2 lossily compresses the voltage data based on the compression ratio received in step S21 to create the transmission data. Note that each voltage detection device 2 may generate transmission data that does not include the diagnostic information generated by the diagnosis unit 2c and the control information created by the control instruction unit 2d.

[0047] Then, each voltage detecting device 2 transmits the transmission data created in step S22 to the management device 3 (step S23). Here, each voltage detecting device 2 transmits the transmission data from the transmitting unit 3e to the management device 3.

[0048] The transmission data transmitted from each voltage detecting device 2 is received by the management device 3. The management device 3 executes step S11 again based on the voltage data included in the transmission data transmitted from each voltage detecting device 2.

[0049] The voltage detection device 2 included in the battery management system 1 of this embodiment as described above is connected to the battery module M and detects the voltage of the battery module M. The voltage detection device 2 includes a voltage acquisition unit 2b, a data generation unit 2e, and a transmission unit 2g. The voltage acquisition unit 2b acquires voltage data of the battery module M. The data generation unit 2e is capable of compressing the voltage data acquired by the voltage acquisition unit 2b, and generates transmission data including the voltage data. The transmission unit 2g transmits the transmission data generated by the data generation unit 2e. In addition, the data generation unit 2e changes the compression rate of the voltage data based on the charging rate of the battery module M.

[0050] In the voltage detection device 2 of this embodiment, the compression rate of the voltage data is changed based on the charging rate of the battery module M. When the data is compressed, the data accuracy may deteriorate. However, the voltage data does not necessarily need to be highly accurate at all times depending on the charging rate of the battery module M. Therefore, by compressing the voltage data according to the charging rate of the battery module M, the amount of data to be transmitted can be reduced compared to when the voltage data is not compressed. Therefore, according to the voltage detection device 2 of this embodiment, in the battery management system 1 in which the voltage detection device 2 and the management device 3 communicate with each other, it is possible to suppress power consumption due to communication.

[0051] The charging rate has a high charging rate range including a charging rate indicating that the voltage of the battery module M is a charging end voltage, a low charging rate range including a charging rate indicating that the voltage of the battery module M is a discharging end voltage, and an intermediate charging rate range between the high charging rate range and the low charging rate range. In such a case, the data generating unit 2e of the voltage detection device 2 of this embodiment sets the compression rate of the voltage data in the high charging rate range and the low charging rate range lower than that in the intermediate charging rate range.

[0052] The voltage detection device 2 of the present embodiment increases the compression rate of the voltage data when the charging rate of the battery module M is in the intermediate charging rate range. This makes it possible for the voltage detection device 2 to reduce power consumption due to communication.

[0053] In the voltage detection device 2 of this embodiment, the data generator 2e decreases the compression rate in the high charging rate range as the charging rate increases, and decreases the compression rate in the low charging rate range as the charging rate decreases. The voltage detection device 2 of this embodiment can prevent the compression rate of the voltage data from changing suddenly with the change in the charging rate.

[0054] Moreover, in the voltage detecting device 2 of the present embodiment, the data generating unit 2e generates transmission data including information different from the voltage data. The voltage detecting device 2 of the present embodiment can transmit the voltage data and the information different from the voltage data at the same time.

[0055] Moreover, in the voltage detection device 2 of this embodiment, the data generation unit 2e lossily compresses the voltage data and losslessly compresses or uncompresses information different from the voltage data to generate transmission data. The voltage detection device 2 of this embodiment can transmit, for example, data to be lossily compressed and data to be losslessly compressed simultaneously. The voltage detection device 2 of this embodiment can also transmit, for example, data to be lossily compressed and data that is not compressed simultaneously.

[0056] Furthermore, in the voltage detection device 2 of this embodiment, information different from the voltage data includes at least one of diagnostic information of the voltage detection device 2 and control information output from the voltage detection device 2 to an external device. The voltage detection device 2 of this embodiment can transmit either or both of the diagnostic information and the control information with high accuracy.

[0057] The battery management system 1 in this embodiment also includes a voltage detection device 2 and a management device 3. The voltage detection device 2 detects the voltage of a battery module M mounted on a vehicle. The management device 3 is capable of wireless communication with the voltage detection device 2 and manages the battery module M based on transmission data input from the voltage detection device 2. As described above, the voltage detection device 2 is capable of reducing power consumption due to communication. Therefore, the battery management system 1 in this embodiment is also capable of reducing power consumption due to communication.

[0058] Although the preferred embodiment of the present invention has been described above with reference to the attached drawings, it goes without saying that the present invention is not limited to the above embodiment. The shapes and combinations of the components shown in the above embodiment are merely examples, and various modifications can be made based on design requirements, etc., without departing from the spirit of the present invention.

[0059] For example, in the above embodiment, a configuration has been described in which the voltage detection device 2 and the management device 3 perform wireless communication. However, the present invention is not limited to this. The present invention can also be applied to a voltage detection device that performs wired communication with a management device. The present invention can also be applied to a battery management system in which the voltage detection device and the management device are connected by wire.

[0060] The above embodiment can also be described as, for example, the following supplementary notes.

[0061] (Appendix 1) A voltage detection device connected to a battery module to detect a voltage of the battery module, A voltage acquisition unit that acquires voltage data of the battery module; a data generating unit capable of compressing the voltage data acquired by the voltage acquiring unit and generating transmission data including the voltage data; a transmission unit that transmits the transmission data generated by the data generation unit; Equipped with The data generating unit changes a compression rate of the voltage data based on a charging rate of the battery module. A voltage detection device comprising:

[0062] (Appendix 2) the charging rate has a high charging rate range including a charging rate indicating that the voltage of the battery module is a charging end voltage, a low charging rate range including a charging rate indicating that the voltage of the battery module is a discharging end voltage, and an intermediate charging rate range between the high charging rate range and the low charging rate range, The data generating unit sets a compression rate of the voltage data in the high charging rate range and the low charging rate range lower than that in the intermediate charging rate range. 2. A voltage detection device according to claim 1.

[0063] (Appendix 3) The voltage detection device according to claim 2, wherein the data generation unit decreases the compression rate in the high charging rate range as the charging rate increases, and decreases the compression rate in the low charging rate range as the charging rate decreases.

[0064] (Appendix 4) 4. The voltage detection device according to claim 1, wherein the data generation unit generates the transmission data including information different from the voltage data.

[0065] (Appendix 5) The voltage detection device according to claim 4, wherein the data generation unit generates the transmission data by lossy compressing the voltage data and losslessly compressing or uncompressing information different from the voltage data.

[0066] (Appendix 6) 6. The voltage detection device according to claim 5, wherein the information different from the voltage data includes at least one of diagnostic information of the voltage detection device and control information output from the voltage detection device to an external device.

[0067] (Appendix 7) A battery management system including: a voltage detection device that detects a voltage of a battery module mounted on a vehicle; and a management device that is capable of communicating with the voltage detection device and manages the battery module based on transmission data input from the voltage detection device, The voltage detection device includes the voltage detection device according to any one of Supplementary Notes 1 to 6. A battery management system comprising: [Explanation of symbols]

[0068] 1 Battery Management System 2. Voltage detection device 2a Wireless communication antenna 2b Voltage acquisition section 2c Diagnostics Department 2d control instruction section 2e Data Generation Division 2f Receiving section 2g transmitter 3 Management device 3a Wireless communication antenna 3b Charging rate calculation section 3c Compression ratio setting section 3d Receiver 3e Transmitter M Battery Module

Claims

1. A voltage detection device connected to a battery module to detect a voltage of the battery module, A voltage acquisition unit that acquires voltage data of the battery module; a data generating unit capable of compressing the voltage data acquired by the voltage acquiring unit and generating transmission data including the voltage data; a transmission unit that transmits the transmission data generated by the data generation unit; Equipped with The data generating unit changes a compression rate of the voltage data based on a charging rate of the battery module. A voltage detection device comprising:

2. the charging rate has a high charging rate range including a charging rate indicating that the voltage of the battery module is a charging end voltage, a low charging rate range including a charging rate indicating that the voltage of the battery module is a discharging end voltage, and an intermediate charging rate range between the high charging rate range and the low charging rate range, The data generating unit sets a compression rate of the voltage data in the high charging rate range and the low charging rate range lower than that in the intermediate charging rate range.

2. The voltage detection device according to claim 1.

3. 3. The voltage detection device according to claim 2, wherein the data generation unit decreases the compression rate in the high charging rate range as the charging rate increases, and decreases the compression rate in the low charging rate range as the charging rate decreases.

4. 3. The voltage detection device according to claim 1, wherein the data generating unit generates the transmission data including information different from the voltage data.

5. 5. The voltage detection device according to claim 4, wherein the data generating section generates the transmission data by lossy compressing the voltage data and losslessly compressing or uncompressing information different from the voltage data.

6. 6. The voltage detection device according to claim 5, wherein the information different from the voltage data includes at least one of diagnostic information of the voltage detection device and control information output from the voltage detection device to an external device.

7. A battery management system including: a voltage detection device that detects a voltage of a battery module mounted on a vehicle; and a management device that is capable of communicating with the voltage detection device and manages the battery module based on transmission data input from the voltage detection device, The voltage detection device includes the voltage detection device according to any one of claims 1 to 3. A battery management system comprising:

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