Battery management device and method

Abstract

A battery management device according to one embodiment disclosed in this document may include a power supply unit including a plurality of power sources, a measurement unit that applies a first power source among the plurality of power sources to a battery cell to measure a first voltage, and applies a second power source among the plurality of power sources different from the first power source to the battery cell to measure a second voltage, and a calculation unit that calculates a voltage of the battery cell based on the first voltage and the second voltage.

Description

[Technical field]

[0001] The embodiments disclosed in this document claim the benefit of priority based on Korean Patent Application No. 10-2021-0102179, filed on August 3, 2021, and all contents disclosed in the documents of this Korean patent application are incorporated as part of this specification. SUMMARY OF THE DISCLOSURE The embodiments disclosed herein relate to battery management apparatus and methods. [Background technology]

[0002] A secondary battery is generally used as a battery pack including a battery module in which a plurality of battery cells are connected in series and / or parallel, and the state and operation of the battery pack are managed and controlled by a battery management system.

[0003] Today, as the demand for such secondary batteries increases, the importance of battery management systems (BMS) that manage battery packs or battery modules also increases. In general, such battery management systems essentially include a BMIC circuit that measures voltage and balances battery cells.

[0004] Using such a BMIC circuit, it is easy to measure the voltage of a battery cell, but due to the current required to run the BMIC circuit and the voltage drop caused by the internal resistance of the battery cell, a voltage error will occur in the case of battery cells located at both ends of a battery module.

[0005] In this way, the battery cells at both ends of the battery module are always measured to have a lower voltage than the other battery cells, and therefore, in order to correct such errors, a separate voltage measuring device is usually required. Summary of the Invention [Problem to be solved by the invention]

[0006] One objective of the embodiments disclosed in this document is to provide a battery management device and method that can automatically correct errors caused by internal resistance when measuring the voltage of a battery cell without the need for a separate device.

[0007] The technical problems of the embodiments disclosed in this document are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0008] A battery management device according to one embodiment disclosed in this document may include a power supply unit including a plurality of power sources, a measurement unit that applies a first power source among the plurality of power sources to a battery cell to measure a first voltage and applies a second power source among the plurality of power sources different from the first power source to the battery cell to measure a second voltage, and a calculation unit that calculates a voltage of the battery cell based on the first voltage and the second voltage.

[0009] In one embodiment, the calculation unit can calculate the voltage of the battery cell based on the difference between the first voltage and the second voltage. According to one embodiment, the calculation unit can calculate an internal resistance of the battery cell based on the first voltage and the second voltage. In one embodiment, the calculation unit can correct the voltage of the battery cell based on an internal resistance of the battery cell.

[0010] According to an embodiment, the battery cell may be a battery cell provided at one end of a battery module. According to one embodiment, the plurality of power sources may be power sources for driving a BMIC circuit that manages the battery cells.

[0011] A battery management method according to one embodiment disclosed in this document may include the steps of applying a first power source of a plurality of power sources to a battery cell and measuring a first voltage, applying a second power source of the plurality of power sources different from the first power source to the battery cell and measuring a second voltage, and calculating a voltage of the battery cell based on the first voltage and the second voltage.

[0012] According to one embodiment, the step of calculating the voltage of the battery cell may calculate the voltage of the battery cell based on a difference between the first voltage and the second voltage.

[0013] According to an embodiment, the step of calculating the voltage of the battery cell may include calculating an internal resistance of the battery cell based on the first voltage and the second voltage. In one embodiment, the step of calculating the voltage of the battery cell may correct the voltage of the battery cell based on an internal resistance of the battery cell. Effect of the Invention

[0014] The battery management device and method according to an embodiment disclosed herein can automatically correct errors caused by internal resistance when measuring the voltage of a battery cell without the need for a separate device. [Brief description of the drawings]

[0015] [Figure 1] 1 is a diagram illustrating a schematic configuration of a battery control system including a battery management device according to an embodiment disclosed in this document. [Diagram 2] 1 is a block diagram showing a configuration of a battery management device according to an embodiment disclosed in this document. [Diagram 3] FIG. 1 is a diagram showing a conventional battery module and a battery management device. [Figure 4] FIG. 1 illustrates a battery module and a battery management device according to one embodiment disclosed herein. [Diagram 5] 1 is a flow chart illustrating a battery management method according to one embodiment disclosed herein. [Figure 6] FIG. 2 is a block diagram showing the hardware configuration of a computing system for implementing a battery management method according to an embodiment disclosed herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, various embodiments disclosed in the present document will be described in detail with reference to the accompanying drawings. In this document, the same components in the drawings are designated by the same reference numerals, and duplicated descriptions of the same components will be omitted.

[0017] For the various embodiments disclosed in this document, specific structural or functional descriptions are set forth merely for purposes of describing the embodiments, and the various embodiments disclosed in this document may be embodied in various forms and should not be construed as being limited to the embodiments described in this document.

[0018] The terms "first," "second," "first," or "second" used in the various embodiments may modify various elements without regard to order and / or importance and do not limit such elements. For example, a first element may be named a second element, and similarly, the second element may be renamed to the first element without departing from the scope of the embodiments disclosed herein.

[0019] The terms used in this document are merely used to describe a particular embodiment and are not intended to limit the scope of other embodiments. A singular expression may include a plural expression unless otherwise clearly indicated in the context.

[0020] All terms used herein, including technical or scientific terms, may have the same meaning as commonly understood by a person of ordinary skill in the art of the embodiments disclosed herein. Terms defined in commonly used dictionaries may be interpreted to have the same or similar meaning in the context of the relevant art, and are not interpreted in an ideal or overly formal sense unless expressly defined in this document. In some cases, even terms defined in this document should not be interpreted to exclude the embodiments disclosed herein.

[0021] FIG. 1 is a diagram illustrating a schematic configuration of a battery control system including a battery management device according to an embodiment disclosed in this document. 1, a battery control system 1 may include a battery pack 10 and a host controller 20. The battery pack 10 may include a battery module 12, a sensor 14, a switching unit 16, and a battery management system (BMS) 100. In this case, the battery pack 10 may include a plurality of battery modules 12, sensors 14, switching units 16, and battery management systems 100. The battery packs 10 may be connected in series or parallel and communicate with an externally provided host controller 20.

[0022] The battery module 12 may include one or more battery cells that can be charged and discharged. In this case, the battery modules 12 may be connected in series or in parallel. The sensor 14 may detect a current flowing through the battery pack 10. In this case, a current detection signal may be transmitted to the battery management device 100. The switching unit 16 may be connected in series to the (+) terminal side and the (-) terminal side of the battery module 12, and may control the flow of charge / discharge current of the battery module 12. For example, the switching unit 16 may use at least one switch, relay, electromagnetic contactor, etc. according to the specifications of the battery pack 10.

[0023] The battery management device 100 can monitor the voltage, current, temperature, etc. of the battery pack 10, and control and manage it to prevent overcharging, over-discharging, etc., and for example, the battery management device 100 may be a BMS of the battery pack.

[0024] The battery management device 100 is an interface that receives input of measured values ​​of various parameters, and may include a plurality of terminals, and a circuit connected to these terminals for processing the received values. The battery management device 100 may also control the ON / OFF of a switching unit 16, such as a switch, relay, or contactor, and may be connected to a plurality of battery modules 12 to monitor the states of the battery cells.

[0025] Meanwhile, the battery management device 100 disclosed in this document can measure the voltage of each battery cell included in the battery module 12 via the BMIC. Also, the battery management device 100 can apply driving currents of a plurality of BMICs to measure the voltage of the battery cells and calculate the internal resistance of the battery cells based on the measured voltage. In this way, the battery management device 100 can correct the voltage measurement error of the battery cells caused by the internal resistance of the battery cells. The configuration of such a battery management device 100 will be described in detail later with reference to FIG. 2.

[0026] The upper controller 20 can transmit various control signals for the battery module 12 to the battery management device 100. As a result, the operation of the battery management device 100 can be controlled based on the signals applied from the upper controller 20. Meanwhile, the battery cell of the present disclosure may be configured to be included in a battery module 12 used in an electric vehicle. However, the battery pack 10 of FIG. 1 is not limited to such an application, and for example, a battery rack of an energy storage system (ESS) can be included instead of the battery pack 10 of FIG. 1.

[0027] FIG. 2 is a block diagram showing a configuration of a battery management device according to an embodiment disclosed in this document. Referring to FIG. 2, a battery management device 100 according to an embodiment disclosed herein may include a power supply unit 110, a measurement unit 120, and a calculation unit .

[0028] The power supply unit 110 may include a plurality of power supplies. In this case, the plurality of power supplies included in the power supply unit 110 may be driving power supplies of a BMIC circuit that manages the battery cells. For example, the power supply unit 110 may control the plurality of power supplies via a switching circuit.

[0029] The measurement unit 120 may apply a power source of the power source unit 110 to the battery cell to measure a voltage of the battery cell. For example, the measurement unit 120 may apply a first power source of the plurality of power sources to the battery cell to measure a first voltage, and apply a second power source of the plurality of power sources different from the first power source to the battery cell to measure a second voltage. In this case, the battery cell may be a battery cell provided at one end of a battery module.

[0030] The calculation unit 130 can calculate the voltage of the battery cell based on the first voltage and the second voltage measured by applying the first power source and the second power source to the battery cell, respectively. For example, the calculation unit 130 can calculate the voltage of the battery cell based on the difference between the first voltage and the second voltage. At this time, the calculation unit 130 can calculate the internal resistance of the battery cell based on the first voltage and the second voltage measured for the battery cell. Thereby, the calculation unit 130 can correct the voltage of the battery cell based on the internal resistance of the battery cell. A specific voltage calculation method of the calculation unit 130 will be described later with reference to FIGS. 3 and 4.

[0031] In this manner, the battery management device 100 according to an embodiment disclosed in this document can automatically correct errors caused by internal resistance when measuring the voltage of a battery cell without the need for a separate device.

[0032] Fig. 3 is a diagram showing a conventional battery module and a battery management device, and Fig. 4 is a diagram showing a battery module and a battery management device according to an embodiment disclosed in the present document.

[0033] Referring to FIG. 3, in the case of a conventional battery management device, when measuring the voltage of a battery cell 202 provided at one end of a battery module 12, a driving current I cc and the internal resistance component R of the battery cell 202 b In this case, a voltage drop occurs due to I cc >>I CVn Therefore, the remaining battery cells are not affected by the voltage drop. On the other hand, the internal resistance of the battery cells R b is difficult to measure directly.

[0034] In this way, according to the conventional battery management device, the internal resistance R b As a result, the voltage of the battery cell 202 at one end of the battery module 12 is always measured to be lower than that of the other battery cells, and in order to correct this, the voltage must be remeasured using a separate voltage measuring device.

[0035] 4, the battery management device 100 according to an embodiment disclosed herein can selectively receive a driving current for the BMIC from a first power source 111 and a second power source 112. That is, in the battery management device 100 according to an embodiment disclosed herein, after applying a driving current for the BMIC from the first power source 111, a first voltage of the battery cell 202 can be measured via the measurement unit 120, and after applying a driving current for the BMIC from the second power source 112, a second voltage of the battery cell 202 can be measured via the measurement unit 120.

[0036] In addition, the battery management device 100 according to the embodiment disclosed in this document calculates the internal resistance R of the battery cell based on the difference between the first voltage and the second voltage measured in this manner. b Then, the battery management unit 100 calculates the calculated internal resistance R b and the BMIC drive current I cc , I cc1can be used to correct the voltage error of the battery cell 202. At this time, in the case of the remaining battery cells such as the battery cell 201, there is no effect of the voltage drop due to the driving current of the BMIC, so no separate correction is required.

[0037] Specifically, the calculation unit 130 of the battery management device 100 according to an embodiment disclosed herein may calculate the voltage of the battery cell 202 by the following mathematical formula: cc The voltage of the battery cell 202 when a voltage of 0.1 V is applied thereto can be expressed as follows (L2) according to Kirchhoff's Voltage Law:

[0038] [Mathematical formula 1] TIFF0007666590000001.tif27150

[0039] In addition, the drive current (I cc1 ) is applied to the battery cell 202, the voltage of which can be expressed as follows:

[0040] [Mathematical formula 2] TIFF0007666590000002.tif26146

[0041] V cn : Battery cell voltage, V Cn_ic : Battery cell voltage measured by BMIC R b : Internal resistance of the battery cell R p : Resistance of the path connecting the BMIC and the battery cell I Cvn : The current flowing through the pin when measuring the voltage of a battery cell I cc , I cc1 :BMIC drive current

[0042] In this manner, the calculation unit 130 of the battery management device 100 according to the embodiment disclosed in this document calculates the internal resistance R of the battery cell by simultaneously performing calculations using the mathematical formula 1 and the mathematical formula 2. b and the battery cell voltage V C1 That is, the driving current I cc , I cc1 and the calculated internal resistance of the battery cell R b The measured battery cell voltage V cn_ic can be corrected.

[0043] FIG. 5 is a flow chart illustrating a battery management method according to one embodiment disclosed herein. Referring to FIG. 5, a battery management method according to an embodiment disclosed herein may first apply a first power source among a plurality of power sources to a battery cell to measure a first voltage (S110). Also, a second power source among the plurality of power sources may be applied to the battery cell to measure a second voltage (S120). In this case, the battery cell may be a battery cell provided at one end of a battery module. Also, the plurality of power sources may be driving power sources of a BMIC circuit that manages the battery cell. For example, the plurality of power sources may be controlled via a switching circuit.

[0044] Next, the voltage of the battery cell can be calculated based on the first voltage and the second voltage (S130). For example, in step S130, the voltage of the battery cell can be calculated based on the difference between the first voltage and the second voltage. At this time, the internal resistance of the battery cell can be calculated based on the first voltage and the second voltage measured for the battery cell. Thereby, in step S130, the voltage of the battery cell can be corrected based on the internal resistance of the battery cell.

[0045] In this manner, the battery management method according to an embodiment disclosed herein can automatically correct errors caused by internal resistance when measuring the voltage of a battery cell without the need for a separate device.

[0046] FIG. 6 is a block diagram showing a hardware configuration of a computing system for implementing a battery management method according to an embodiment disclosed in this document. Referring to FIG. 6, a computing system 1000 according to one embodiment disclosed in this document may include an MCU 1010, a memory 1020, an input / output I / F 1030, and a communication I / F 1040.

[0047] The MCU 1010 may be a processor that executes various programs (e.g., a battery cell voltage measurement program, a battery cell internal resistance and voltage calculation program, etc.) stored in the memory 1020, processes various data including the battery cell voltage and internal resistance through such programs, and performs the functions of the battery management device shown in Figure 2 described above.

[0048] The memory 1020 can store various programs relating to battery cell voltage measurement, internal resistance and voltage calculation, etc. The memory 1020 can also store various data such as the voltage and internal resistance of the battery cell.

[0049] A plurality of such memories 1020 may be provided as necessary. The memory 1020 may be a volatile memory or a non-volatile memory. The memory 1020 as a volatile memory may be a RAM, a DRAM, an SRAM, or the like. The memory 1020 as a non-volatile memory may be a ROM, a PROM, an EAROM, an EPROM, an EEPROM, a flash memory, or the like. The examples of the memory 1020 listed above are merely illustrative and are not limited to these examples.

[0050] The input / output I / F 1030 can provide an interface that connects input devices (not shown) such as a keyboard, mouse, or touch panel, and output devices such as a display (not shown), to the MCU 1010 to enable data transmission and reception.

[0051] The communication I / F 1040 is configured to be able to transmit and receive various data to and from a server, and may be any of various devices capable of supporting wired or wireless communication. For example, programs and various data for measuring the voltage of a battery cell and calculating the internal resistance and voltage can be transmitted and received from a separately provided external server via the communication I / F 1040.

[0052] In this manner, a computer program according to one embodiment disclosed in this document may be recorded in memory 1020 and processed by MCU 1010 to be realized, for example, as a module performing each function shown in FIG. 2.

[0053] Although it has been described above that all components constituting the embodiments disclosed in this document are combined or operate in combination, the embodiments disclosed in this document are not necessarily limited to such embodiments. In other words, within the scope of the purpose of the embodiments disclosed in this document, all components may be selectively combined and operate in one or more combinations.

[0054] In addition, the terms "comprise", "constitute", or "have" described above mean that the relevant element can be contained, unless otherwise specified, and should be interpreted as meaning that other elements may be included, rather than excluding other elements. All terms, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the embodiments disclosed in this document belong, unless otherwise defined. Commonly used terms, such as terms defined in a dictionary, should be interpreted as consistent with the contextual meaning of the relevant art, and should not be interpreted in an idealized or overly formal sense, unless expressly defined in this document.

[0055] The above description is merely an illustrative example of the technical ideas disclosed in this document, and a person having ordinary knowledge in the technical field to which the embodiments disclosed in this document belong can make various modifications and variations within the scope of the essential characteristics of the embodiments disclosed in this document. Therefore, the embodiments disclosed in this document are intended to explain, not to limit, the technical ideas of the embodiments disclosed in this document, and such embodiments do not limit the scope of the technical ideas disclosed in this document. The scope of protection of the technical ideas disclosed in this document should be interpreted according to the claims below, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of rights of this document.

Claims

1. a power supply unit including a plurality of power sources; a measurement unit that applies a first power source among the plurality of power sources to a battery cell to measure a first voltage, and applies a second power source among the plurality of power sources, different from the first power source, to the battery cell to measure a second voltage; a calculation unit that calculates a voltage of the battery cell based on the first voltage and the second voltage; Including, The calculation unit calculates a voltage of the battery cell based on a difference between the first voltage and the second voltage.

2. The battery management device according to claim 1 , wherein the calculation unit calculates the internal resistance of the battery cell based on the first voltage and the second voltage.

3. The battery management device according to claim 2 , wherein the calculation unit corrects the voltage of the battery cell based on the internal resistance of the battery cell.

4. The battery management device according to claim 1 , wherein the battery cell is a battery cell provided at one end of a battery module.

5. 4. The battery management device according to claim 1, wherein the plurality of power sources are driving power sources for a BMIC circuit that manages the battery cells.

6. A power supply unit including a plurality of power sources; a measurement unit that applies a first power source among the plurality of power sources to a battery cell to measure a first voltage, and applies a second power source among the plurality of power sources, different from the first power source, to the battery cell to measure a second voltage; a calculation unit that calculates a voltage of the battery cell based on the first voltage and the second voltage; Including, The battery management device, wherein the plurality of power sources are driving power sources for a BMIC circuit that manages the battery cells.

7. applying a first power source of the plurality of power sources to the battery cell and measuring a first voltage; applying a second power source, which is different from the first power source among the plurality of power sources, to the battery cell and measuring a second voltage; calculating a voltage of the battery cell based on the first voltage and the second voltage; Including, The step of calculating the voltage of the battery cell calculates the voltage of the battery cell based on a difference between the first voltage and the second voltage.

8. The battery management method according to claim 7 , wherein the step of calculating the voltage of the battery cell includes calculating an internal resistance of the battery cell based on the first voltage and the second voltage.

9. The battery management method according to claim 8 , wherein the step of calculating the voltage of the battery cell includes correcting the voltage of the battery cell based on the internal resistance of the battery cell.

10. A method of measuring a first voltage by applying a first power source of a plurality of power sources to a battery cell; applying a second power source, which is different from the first power source among the plurality of power sources, to the battery cell and measuring a second voltage; calculating a voltage of the battery cell based on the first voltage and the second voltage; Including, The battery management method, wherein the plurality of power sources are driving power sources for a BMIC circuit that manages the battery cells.

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