System for managing a battery

Abstract

A system for managing batteries uses a single converter to perform bidirectional charge / discharge active cell balancing of multiple battery cells, thereby reducing the number of components required for active cell balancing and achieving a reduction in cost and size of the system for managing batteries.

Description

Technical Field

[0001] This disclosure relates to a system for managing batteries. Background Technology

[0002] As battery technology advances and battery capacity gradually increases, the tolerance of the state-of-charge (SOC) capacity of individual cells within a single battery pack, which contains multiple battery cells, is also increasing. To ensure the safety of battery pack use, it is necessary to equalize the SOC of each battery cell through cell balancing.

[0003] However, conventional cell equalization is a passive method that simply uses resistive elements to dissipate the voltage of cells with a high state of charge (SOC) through heat loss. This passive method requires an equalization current in the mA range, which is very small compared to the cell capacity. This limits the cell equalization operation time to be very long.

[0004] To perform balancing in a shorter time compared to this passive method, active cell balancing is required to increase the balancing current to the ampere level. Conventional active cell balancing solutions require a DC-DC converter (external inductor or external transformer) for each battery cell, which significantly increases the cost of the battery management system (BMS) and also significantly increases the size of the BMS board.

[0005] Figure 1 This is a diagram illustrating a battery management system that performs routine active cell balancing.

[0006] In other words, such as Figure 1 As shown, conventional active cell balancing technology requires one DC-DC converter for each battery cell. This DC-DC converter also requires an inductor (or transformer). This means a considerable number of components are needed. For example, if there are 20 battery cells in a battery pack, then 20 DC-DC converters and 20 inductors (or transformers) are needed within the battery management system (BMS). Summary of the Invention

[0007] Technical issues

[0008] According to embodiments of this disclosure, a system for managing batteries can be provided that uses a single converter to perform bidirectional charge / discharge active cell balancing of multiple battery cells.

[0009] The aspects to be achieved in this disclosure are not limited to those described above, and may be extended in various ways without departing from the spirit and scope of this disclosure.

[0010] Technical solution

[0011] A system for managing a battery according to an embodiment of the present disclosure includes: a battery pack including a plurality of battery cells; and a battery management device including a single converter and configured to perform bidirectional charge / discharge active cell equalization of the plurality of battery cells using the single converter.

[0012] The battery management device can control a single converter to operate in one of a first operating mode and a second operating mode, in which multiple individual battery cell voltages are input and a battery pack voltage is output, and in the second operating mode, a battery pack voltage is input and multiple individual battery cell voltages are output.

[0013] When a single converter operates in a first operating mode, the battery management device can perform an active cell equalization discharge operation, in which the voltages of at least two of the multiple battery cells are input to the single converter, and the battery pack is charged using a battery pack voltage output from the single converter.

[0014] When a single converter operates in the second operating mode, the battery management device can perform an active cell equalization charging operation, in which the battery pack voltage is input to the single converter, and multiple cell voltages output from the single converter are used to charge multiple cell batteries.

[0015] A single converter may include two first switches connected to each of the multiple battery cells.

[0016] A single converter may further include a second switch connected to the battery pack.

[0017] A single converter may further include an inductor having one end connected to a first switch and the other end connected to a second switch, the first switch being connected to each of a plurality of battery cells and the second switch being connected to a battery pack.

[0018] A single converter may further include a transformer having one end connected to a first switch and the other end connected to a second switch, the first switch being connected to each of the plurality of battery cells and the second switch being connected to the battery pack.

[0019] The battery management device can control the on / off state of the first and second switches, enabling a single converter to operate in one of the first and second operating modes to perform bidirectional charging / discharging active cell balancing.

[0020] The battery management device can control the first switch to be turned on first, and then control the second switch to be turned on, so that the individual converter operates in a first operating mode to perform active cell equalization discharge operation.

[0021] The battery management device can control the second switch to be turned on first, and then control the first switch to be turned on, so that the individual converter operates in a second operating mode to perform active single-cell equalization charging operation.

[0022] The battery management device may include N converters and use the N converters to perform bidirectional charging / discharging active cell balancing of multiple battery cells, where N is less than the number of battery cells M.

[0023] N converters can perform bidirectional charging / discharging active cell balancing for different cells among multiple battery cells.

[0024] Beneficial effects

[0025] According to embodiments of this disclosure, the number of components required for active cell balancing can be reduced by using a single converter to perform bidirectional charge / discharge active cell balancing of multiple battery cells, thereby achieving cost and size reduction of the system for managing batteries.

[0026] The effects of various embodiments of this disclosure are not limited to the effects described above, and it will be apparent to those skilled in the art that various effects are inherent in this disclosure. Attached Figure Description

[0027] Figure 1 This is a diagram illustrating a battery management system that performs routine active cell balancing.

[0028] Figure 2 This is a block diagram illustrating a system for managing batteries according to an embodiment of the present disclosure.

[0029] Figure 3 It's a diagram. Figure 2 A block diagram showing the configuration of a single converter.

[0030] Figure 4 This is a diagram illustrating an example of a system for managing batteries according to an embodiment of the present disclosure.

[0031] Figure 5 It's a diagram. Figure 4 The diagram shows the active single-cell equalization discharge operation of the system used to manage the battery.

[0032] Figure 6 It's a diagram. Figure 4 The diagram shows the active cell equalization charging operation of a system for managing batteries.

[0033] Figure 7 This is a diagram illustrating another example of a system for managing batteries according to an embodiment of the present disclosure. Detailed Implementation

[0034] In the following, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Referring to the following and accompanying drawings... Figure 1 The advantages and features of the embodiments of this disclosure, as well as the methods of implementing them, will become clear from the detailed description herein. However, the embodiments of this disclosure are not limited to those described below, but can be implemented in various different forms, and the embodiments of this disclosure are limited only by the scope of the claims.

[0035] Throughout this specification, the same reference numerals refer to the same elements. Unless otherwise specified, all terms used herein (including technical and scientific terms) may be used in the sense that would be commonly understood by one of ordinary skill in the art to which embodiments of this disclosure pertain. Furthermore, unless explicitly defined, terms as defined in commonly used dictionaries should not be interpreted ideally or excessively.

[0036] In this disclosure, the terms "first," "second," etc., are used to distinguish a specific component from other components, and the aforementioned components are not limited by these terms. For example, the term "first component" can be used to refer to an element of the same or similar form as the term "second component."

[0037] In this specification, for ease of explanation, each step is identified by a symbol (e.g., a, b, c, etc.), and the symbols do not describe the order of the steps, and the steps may occur in a different order than stated unless the context clearly indicates a specific order. That is, the steps may occur in the same order as stated, may be performed substantially simultaneously, or may be performed in the reverse order.

[0038] In this disclosure, terms such as “comprising” or “including” may indicate the presence of features (e.g., numerical values, functions, operations, or components such as parts), but such terms do not exclude additional features.

[0039] Furthermore, the term "~component" described in this specification refers to a software or hardware component, such as a Field Programmable Gate Array (FPGA) or an ASIC, and "~component" performs certain roles. However, "~component" is not limited to software or hardware. "~component" can be configured to reside in addressable memory and can be configured to operate one or more processors. Thus, by way of example, "~component" includes components such as software components, object-oriented software components, class components and task components, processes, functions, attributes, procedures, subroutines, program code segments, drivers, firmware, microcode, circuits, data structures, and variables. The functionality provided in components and "~components" can be combined into a smaller number of components and "~components" or further divided into additional components and "~components".

[0040] In the following, a system for managing batteries according to embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0041] First, refer to Figure 2 and Figure 3 A system for managing batteries according to embodiments of the present disclosure is described.

[0042] Figure 2 This is a block diagram illustrating a system for managing a battery according to an embodiment of the present disclosure, and Figure 3 It's a diagram. Figure 2 A block diagram showing the configuration of a single converter.

[0043] refer to Figure 2 A system for managing a battery according to embodiments of the present disclosure may include a battery management device 100 and a battery pack 200 connected to the battery management device 100.

[0044] The battery pack 200 may include multiple battery cells 210 that constitute a secondary battery.

[0045] The battery management device 100 includes a single converter 110, and the single converter 110 can be used to perform bidirectional charge / discharge active cell balancing of multiple battery cells 210.

[0046] Therefore, the battery management device 100 can control a single converter 110, causing the single converter 110 to operate in one of a first operating mode and a second operating mode. Here, the first operating mode may be a mode in which the voltages of multiple individual battery cells are input and the voltage of a battery pack is output. The second operating mode may be a mode in which the voltage of one battery pack is input and the voltages of multiple individual battery cells are output.

[0047] Here, as Figure 3As shown, a single converter 110 may include two first switches 111 connected to each of the plurality of battery cells 210, a second switch 112 connected to the battery pack 200, and a conversion module 113 that converts the input voltage and outputs the output voltage.

[0048] At this time, the first switch 111 may include a first switch 111-P connected to the positive terminal of the battery cell 210 and a first switch 111-N connected to the negative terminal of the battery cell 210.

[0049] Additionally, one end of the conversion module 113 can be connected to a first switch 111, which is connected to each of the plurality of battery cells 210, and the other end of the conversion module 113 can be connected to a second switch 112, which is connected to the battery pack 210. The conversion module 113 can be composed of an inductor or a transformer.

[0050] More specifically, when the single converter 110 operates in a first operating mode, the battery management device 100 can perform an active single-cell equalization discharge operation. In this active single-cell equalization discharge operation, the cell voltages of at least two of the plurality of battery cells 210 are input to the single converter 110, and the battery pack 200 is charged using a battery pack voltage output from the single converter 110. Additionally, when the single converter 110 operates in a second operating mode, the battery management device 100 can perform an active single-cell equalization charging operation. In this active single-cell equalization charging operation, the battery pack voltage of the battery pack 200 is input to the single converter 110, and the plurality of battery cells 210 are charged using the multiple cell voltages output from the single converter 110.

[0051] Therefore, the battery management device 100 can perform bidirectional active cell equalization for charging / discharging by controlling the on / off state of the first switch 111 and the second switch 112, causing the individual converter 110 to operate in one of the first and second operating modes. That is, the battery management device 100 can perform active cell equalization discharge by controlling the first switch 111 to be turned on first and then controlling the second switch 112 to be turned on, causing the individual converter 110 to operate in the first operating mode. Alternatively, the battery management device 100 can perform active cell equalization charging by controlling the second switch 112 to be turned on first and then controlling the first switch 111 to be turned on, causing the individual converter 110 to operate in the second operating mode.

[0052] Therefore, the battery management system according to embodiments of the present disclosure can reduce the number of components required for active cell balancing, thereby achieving cost and size reduction for the battery management system.

[0053] The operation of the battery management device 100 is described in more detail. The battery management device 100, which includes a single converter 110, may include a measurement unit (not shown), a storage unit (not shown), and a control unit (not shown), which are functionally separate components.

[0054] The measurement unit can be configured to measure the state information of the battery pack 200. Here, the state information of the battery pack 200 can include the internal and / or external states of the battery pack 200. For example, the measurement unit can measure information such as the voltage, current, temperature, state of charge (SOC), depth of discharge (DOD), internal resistance, state of health (SOH), idle state, overvoltage or overcurrent state, and equalization state of the battery pack 200 as the internal state of the battery pack 200. For this purpose, the measurement unit can be equipped with various sensors, such as voltage sensors and current sensors. As another example, the measurement unit can measure the state information surrounding the battery pack 200, such as temperature, humidity, and smoke, as the external state of the battery pack 200. For this purpose, the measurement unit can be equipped with sensors such as temperature sensors, humidity sensors, and smoke sensors. In this respect, the measurement unit can also be referred to as a sensor.

[0055] The measurement unit can measure the state information of the battery pack 200 in one dimension by measuring voltage, current, temperature, etc. via sensors. Furthermore, the measurement unit can perform two-dimensional processing, such as calculations, on the one-dimensional information obtained. For example, the measurement unit can calculate or estimate the state of the battery pack 200, such as state of charge (SOC), internal resistance, state of health (SOH), and imbalance, based on state information such as voltage, current, and temperature, to measure the state information of the battery pack 200.

[0056] In addition, the measurement unit can send the measured status information of the battery pack 200 to the control unit.

[0057] The storage unit may be configured to store computer-executable instructions or program code, program data, and / or other suitable forms of information for each component of the battery management device 100—namely, the measurement unit and / or the control unit—to perform their functions. The program stored in the storage unit may include a set of instructions executable by the control unit. In embodiments of this disclosure, the storage unit may be a memory (such as volatile memory, non-volatile memory, or a suitable combination thereof), one or more disk storage devices, optical disk storage devices, flash memory devices, other forms of storage media accessible by the battery management device 100 and storing desired information, or a suitable combination thereof.

[0058] In this case, the storage unit can be implemented as an integrated component of another component included in the battery management device 100—such as a component that serves as a control unit. For example, the storage unit can be implemented as an embedded memory installed in a processor that serves as a control unit.

[0059] The control unit can receive measured status information from the measurement unit. The control unit can then use this status information to perform diagnostic and / or control operations on the battery pack 200.

[0060] The control unit can send information based on diagnostic and / or control operations for the battery pack 200 to another component or store such information. Here, the other component may be a component included within the battery management device 100 according to embodiments of this disclosure or a component included in another device located outside the battery management device 100. Specifically, when the target battery pack 200 is installed in a vehicle, the battery management device 100 can send information to a vehicle-side higher-level control system, such as a vehicle control unit (VCU), electronic control unit (ECU), etc., based on diagnostic and / or control operations for the battery pack 200.

[0061] Furthermore, the control unit can use various wired and wireless communication configurations or methods to transmit information based on diagnostic and / or control operations for the battery pack 200. For example, the control unit can use Controller Area Network (CAN) communication to transmit information based on diagnostic and / or control operations for the battery pack 200 to the vehicle-side control system.

[0062] Additionally, the control unit can be configured to control the charging or discharging operation of the battery pack 200 as one of the control operations for the battery pack 200. In this case, the control unit can directly perform charging or discharging control on the battery pack 200. The control unit can also indirectly instruct or control other components located inside or outside the battery management device 100 to perform charging or discharging control.

[0063] Furthermore, the control unit can perform processing operations for each state of the battery pack 200. In this case, the control unit can be configured to perform different processing operations for the corresponding state. Additionally, the control unit can perform at least partially the same processing operations for different states. Moreover, the processing operations performed by the control unit do not necessarily include only active operations, but may also include passive operations. In particular, the processing operations performed by the control unit may include operations that do not perform any control or communication.

[0064] In addition, when the control unit directly performs processing operations on the battery pack 200, the control unit can send the results of the processing to other components.

[0065] Furthermore, the control unit can perform related operations or functions by at least partially and selectively including processors, controllers, application-specific integrated circuits (ASICs), other chipsets, logic circuits, registers, communication modems, data processing devices, etc., known in the art. These operations can be implemented as software, and in this case, the program can be stored in a storage unit. In this regard, the term "control unit" can be replaced by terms such as processors, controllers, and chipsets. Additionally, at least some of the functions of the measurement unit can also be implemented using these components.

[0066] Furthermore, the control unit does not necessarily have to be physically integrated or located in the same place. For example, some of the functions of the control unit can be performed on the side of the battery pack 200, and other functions of the control unit can be performed on the vehicle side.

[0067] More specifically, at least a portion of the control unit can be implemented by a battery management system (BMS). In this case, at least a portion of the control unit can be implemented as part of the battery pack 200. Alternatively, at least a portion of the control unit can be located external to the battery management device 100. For example, at least some functions of the control unit can be implemented by a control device such as a VCU or ECU mounted on the vehicle. Additionally, the measurement unit can be implemented as an integrated or separate component or assembly.

[0068] Reference Figures 4 to 6 Examples of systems for managing batteries according to embodiments of the present disclosure are described.

[0069] Figure 4 This is a diagram illustrating an example of a battery management system according to an embodiment of the present disclosure. Figure 5 It's a diagram. Figure 4 The diagram shown illustrates the active cell equalization discharge operation of a system for managing batteries. Figure 6 It's a diagram. Figure 4 The diagram shows the active cell equalization charging operation of a system for managing batteries.

[0070] refer to Figure 4The DC-DC converter 110, a single converter in the battery management device 100, can perform bidirectional active cell balancing for charging / discharging. More specifically, in the active cell balancing discharge operation, the DC-DC converter receives the cell voltages of cells 1 to N as inputs (multiple voltage inputs) and outputs a Pack+ voltage (a single voltage output), thereby charging the discharging cell using the battery pack voltage. In other words, in the discharge operation, the DC-DC converter has multiple inputs and a single output, and the active cell balancing discharge operation is an operation that discharges the cell and uses the discharged energy to charge the battery pack. On the other hand, in the active cell balancing charging operation, the DC-DC converter performs an operation that redistributes the energy of the battery pack to the cell by receiving the battery pack voltage as input (a single voltage input) and outputting cell voltages (multiple voltage outputs). In other words, in the charging operation, the DC-DC converter has a single input and multiple outputs, and the active cell balancing charging operation is a battery pack that evenly redistributes the energy of the battery pack to the cell. Battery cell charging operation.

[0071] For example, in active single-cell equalization discharge operation (cell battery) In the battery pack, switches SW_P2 and SW_N2, which act as the first switch 111, are first turned on, and then switch SW_Top, which acts as the second switch 112, is turned on, as follows: Figure 5 As shown in the diagram, discharge current flows in the individual battery cells, and charging current flows in the battery pack. Therefore, the energy discharged from the individual battery cells is charged into the battery pack.

[0072] In active single-cell equalization charging operation (battery cell) In the battery pack, the SW_Top switch, which serves as the second switch 112, is first turned on, and then the SW_P2 and SW_N2 switches, which serve as the first switch 111, are turned on, as follows: Figure 6 As shown in the diagram, a discharge current flows through the battery pack, and a charging current flows through the individual battery cells. Therefore, the energy discharged from the battery pack is used to charge the individual battery cells.

[0073] Reference Figure 7 Another example of a system for managing batteries according to embodiments of the present disclosure is described.

[0074] Figure 7 This is a diagram illustrating another example of a system for managing batteries according to an embodiment of the present disclosure.

[0075] The battery management device 100 includes N converters 110 (N is less than M, where M is the number of battery cells 210), and can use the N converters 110 to perform bidirectional charging / discharging active cell balancing of multiple battery cells 210.

[0076] N converters 110 can perform bidirectional charging / discharging active cell balancing on different cells 210 among multiple battery cells 210.

[0077] In other words, although only one converter 110 can be used to perform active cell equalization for all battery cells 210 in the embodiments of this disclosure, fewer converters 110 than the number of battery cells 210 can be used to perform active cell equalization for all battery cells 210, in order to simplify the sequence of active cell equalization operations and improve the cell equalization speed. In this case, converter 110 is used to perform cell equalization for different battery cells 210.

[0078] For example, the battery management system according to embodiments of this disclosure can use not only a single MISISO (Multiple-Input Single-Inductor Single-Output) converter or MISTSO (Multiple-Input Single-Transformer Single-Output) converter as a single converter 110, but also multiple MISISO converters or MISTSO converters, such as... Figure 7 As shown in the diagram. When using multiple converters, the cell equalization sequence becomes less complex than using a single MISISO or MISTSO converter to process all cell cells, and the cell equalization speed can also be increased.

[0079] The operations described above according to the embodiments of this disclosure can be implemented in the form of program instructions, which can be executed by various computer devices and recorded on a computer-readable storage medium. A computer-readable storage medium refers to any medium that participates in providing instructions to a processor for execution. A computer-readable storage medium may include program instructions, data files, data structures, or combinations thereof. For example, a computer-readable storage medium may include magnetic media, optical storage media, memory, etc. Computer programs can be distributed across computer systems connected via a network, and computer-readable code can be stored and executed in a distributed manner. The functional programs, code, and code segments used to implement the embodiments of this disclosure can be readily inferred by a programmer skilled in the art to which the embodiments of this disclosure pertain.

[0080] The embodiments disclosed herein are intended to explain the technical concept, and the scope of the technical concept of the embodiments of this disclosure is not limited to these embodiments. The scope of protection of the embodiments of this disclosure should be interpreted by the appended claims, and all technical concepts within the equivalent scope should be understood to be included within the scope of the rights of the embodiments of this disclosure.

[0081] <Detailed Description of Key Components>

[0082] 100: Battery Management Device

[0083] 110: Single converter

[0084] 111: First Switch

[0085] 112: Second switch

[0086] 113: Conversion Module

[0087] 200: Battery pack

[0088] 210: Battery cell

Claims

1. A system for managing a battery, comprising: The battery pack includes multiple battery cells; as well as A battery management device, the battery management device including a single converter and configured to perform bidirectional charge / discharge active cell equalization of the plurality of battery cells using the single converter.

2. The system according to claim 1, wherein, The battery management device controls the single converter to operate in one of a first operating mode and a second operating mode, in which multiple individual battery cell voltages are input and a battery pack voltage is output, and in the second operating mode, a battery pack voltage is input and multiple individual battery cell voltages are output.

3. The system according to claim 2, wherein, When the single converter operates in the first operating mode, the battery management device performs an active single-cell equalization discharge operation, in which the voltages of at least two of the plurality of battery cells are input to the single converter, and the battery pack is charged using a battery pack voltage output from the single converter.

4. The system according to claim 2, wherein, When the single converter operates in the second operating mode, the battery management device performs an active single-cell equalization charging operation, in which the battery pack voltage of the battery pack is input to the single converter, and the multiple battery cells are charged using the multiple battery cell voltages output from the single converter.

5. The system according to claim 2, wherein, The single converter includes two first switches connected to each of the plurality of battery cells.

6. The system according to claim 5, wherein, The single converter further includes a second switch connected to the battery pack.

7. The system according to claim 6, wherein, The individual converter further includes an inductor having one end connected to the first switch and the other end connected to the second switch, the first switch being connected to each of the plurality of battery cells and the second switch being connected to the battery pack.

8. The system according to claim 6, wherein, The single converter further includes a transformer having one end connected to the first switch and the other end connected to the second switch, the first switch being connected to each of the plurality of battery cells and the second switch being connected to the battery pack.

9. The system according to claim 6, wherein, The battery management device controls the on / off state of the first switch and the second switch, causing the individual converter to operate in one of the first operating modes and the second operating modes to perform bidirectional charging / discharging active cell balancing.

10. The system according to claim 9, wherein, The battery management device controls the first switch to be turned on first, and then controls the second switch to be turned on, so that the individual converter operates in the first operating mode to perform active single-cell equalization discharge operation.

11. The system according to claim 9, wherein, The battery management device controls the second switch to be turned on first, and then controls the first switch to be turned on, so that the individual converter operates in the second operating mode to perform active single-cell equalization charging operation.

12. The system according to claim 1, wherein, The battery management device includes N converters, and uses the N converters to perform bidirectional charging / discharging active cell balancing of the plurality of battery cells, where N is less than the number of battery cells M.

13. The system according to claim 12, wherein, The N converters perform bidirectional charging / discharging active cell balancing on different cells among the plurality of battery cells.

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