Device and method for diagnosing switch damage in a battery protection circuit, and battery management device including the same

Abstract

According to an embodiment of the present invention, there is provided an apparatus and method for diagnosing switch damage in a battery protection circuit, and a battery management device including the same, comprising: a battery protection circuit including one or more battery packs and a switch connected to a positive electrode of the battery pack, and protecting the battery pack from overcharging and overdischarging; and a switch damage diagnosis device including a first switch and a second switch provided as power transistors, measuring a voltage value at at least one point in the battery protection circuit and diagnosing whether or not one of the first switch and the second switch is damaged. Since a source terminal of the first switch and a source terminal of the second switch are commonly grounded, it is possible to diagnose whether or not the switch is damaged only by measuring a voltage at a specific point without measuring a current, and it is possible to charge and discharge the battery pack after checking whether or not the switch is damaged. Thus, it is possible to provide an apparatus and method for diagnosing switch damage in a battery protection circuit, and a battery management device including the same, which provide a highly stable and reliable communication environment that protects the battery pack from abnormal current generation due to overcharging or overdischarging.

Description

[Technical field]

[0001] This application claims the benefit of the filing date of Korean Patent Application No. 10-2021-0184661, filed with the Korean Intellectual Property Office on December 22, 2021, and all of the contents disclosed in the documents of that Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a switch damage diagnosis device and method in a battery protection circuit, and a battery management device including the same, and more specifically, to a switch damage diagnosis device and method for diagnosing whether or not there is switch damage in a battery protection circuit for preventing overcharging and over-discharging of a battery pack, and a battery management device including the same. [Background technology]

[0003] Recently, batteries have been applied to many industrial fields, such as mobile application devices, automobiles, robots, and energy storage devices, as a countermeasure to the problems of environmental regulations and high crude oil prices.

[0004] Generally, battery packs are provided as rechargeable secondary batteries, but such batteries have drawbacks in that they may catch fire when overcharged or may deteriorate when overdischarged, resulting in a shortened lifespan.

[0005] Thus, in order to protect the battery pack, the conventional battery management device provides a battery protection circuit that cuts off the charge or discharge circuit when overcharging or over-discharging occurs.

[0006] The battery protection circuit cuts off the charging and discharging circuit by controlling the operation of a switch connected to one or more battery packs.

[0007] Generally, a switch applied in a battery protection circuit is implemented as a power transistor having a grounded drain terminal.

[0008] However, conventional battery protection circuits have the disadvantage that the accuracy of the measured voltage of the battery pack for controlling the switch operation is reduced due to the characteristics of the parasitic diode generated inside the power transistor, which reduces the reliability of the charge / discharge control operation.

[0009] Therefore, in the past, the voltage and current values ​​at specific points in the battery protection circuit were measured to check whether the switch was damaged.

[0010] However, since the current value can be measured only when the battery pack is being charged or discharged, it is difficult to prevent damage to the battery pack due to the application of an abnormal current. Summary of the Invention [Problem to be solved by the invention]

[0011] SUMMARY OF THE PRESENT EMBODIMENT In order to solve the above problems, an object of the present invention is to provide a battery management device which is highly stable, highly accurate and highly reliable.

[0012] Another object of the present invention to solve the above problems is to provide a highly stable, highly accurate and highly reliable switch damage diagnosis method.

[0013] Another object of the present invention to solve the above problems is to provide a switch damage diagnosis device which is highly stable, highly accurate and highly reliable. [Means for solving the problem]

[0014] To achieve the above object, a battery management device according to one embodiment of the present invention includes a battery protection circuit including a first switch and a second switch connected to a battery pack, and the first switch and the second switch provided as power transistors, and includes a switch damage diagnosis device that measures a voltage value at at least one point in the battery protection circuit to diagnose whether or not one of the first switch and the second switch is damaged, and a source terminal of the first switch and a source terminal of the second switch are commonly grounded.

[0015] Here, the first switch may be a discharge control transistor that controls a discharge circuit when the battery pack is discharged, and the second switch may be a charge control transistor that controls a charge circuit when the battery pack is charged.

[0016] In addition, in the battery protection circuit, a drain terminal of the first switch can be connected to a positive electrode of the battery pack, and a drain terminal of the second switch can be connected to a load.

[0017] Meanwhile, the battery protection circuit may further include a voltage application circuit having one end connected to a first point between the battery pack and a drain terminal of the first switch and another end connected to a second point between a drain terminal of the second switch and the load, bypassing the first switch and the second switch and applying a voltage of the battery pack to the second point.

[0018] In this case, the voltage application circuit may be a switching circuit configured with a P-channel.

[0019] Meanwhile, the at least one point may include a first point between the battery pack and a drain terminal of the first switch, a second point between a drain terminal of the second switch and the load, and a third point where a source of the first switch and a source of the second switch are commonly grounded.

[0020] Furthermore, the switch damage diagnosis device can determine that the first switch and the second switch operate normally when the voltage value at the third point is equal to or lower than a threshold value.

[0021] In addition, the switch damage diagnosis device can determine that the first switch and the second switch are operating normally when the voltage value at the first point and the voltage value at the second point are above a threshold value and the voltage value at the third point is below a threshold value.

[0022] Meanwhile, the switch damage diagnosis device can determine that one of the first switch and the second switch is damaged when the voltage value at the first point or the voltage value at the third point is equal to or greater than a threshold value.

[0023] In accordance with another embodiment of the present invention to achieve the above object, a method for diagnosing whether or not a first switch and a second switch in a battery protection circuit including a first switch and a second switch connected to a battery pack are damaged includes a step of measuring a voltage value at a specific point in the battery protection circuit, and a step of comparing the voltage value with a threshold value to diagnose whether or not the switches are damaged, and includes a step in which a source terminal of the first switch and a source terminal of the second switch are commonly grounded.

[0024] Here, the first switch may be a discharge control transistor that controls a discharge circuit when the battery pack is discharged, and the second switch may be a charge control transistor that controls a charge circuit when the battery pack is charged.

[0025] The battery protection circuit may further include a voltage application circuit having one end connected to a first point between the battery pack and a drain terminal of the first switch and another end connected to a second point between the drain terminal of the second switch and the load, bypassing the first switch and the second switch and applying a voltage of the battery pack to the second point.

[0026] In this case, the voltage application circuit may be a switching circuit configured with a P-channel.

[0027] Meanwhile, the step of measuring a voltage value at a specific point in the battery protection circuit may include a step of measuring a voltage value at a first point between the battery pack and a drain terminal of the first switch, a step of measuring a voltage value at a second point between a drain terminal of the second switch and the load, and a step of measuring a voltage value at a third point where a source of the first switch and a source of the second switch are commonly grounded.

[0028] In addition, the step of comparing the voltage value with a threshold value to diagnose whether the switch is damaged may include a step of determining that the first switch and the second switch are operating normally if the voltage value at the third point is equal to or lower than the threshold value.

[0029] In addition, the step of comparing the voltage value with a threshold value to diagnose whether the switch is damaged may include a step of determining that the first switch and the second switch are operating normally if the voltage value at the first point and the voltage value at the second point are equal to or greater than the threshold value and the voltage value at the third point is equal to or less than the threshold value.

[0030] Meanwhile, the step of comparing the voltage value with a threshold value and diagnosing whether the switch is damaged may include a step of determining that one of the first switch and the second switch is damaged if the voltage value at the first point or the voltage value at the third point is equal to or greater than a threshold value.

[0031] Also, the first switch and the second switch may be high side type power transistors located near the battery pack with respect to the load.

[0032] In accordance with another embodiment of the present invention to achieve the above object, an apparatus for diagnosing whether or not a first switch and a second switch in a battery protection circuit including a first switch and a second switch connected to a battery pack are damaged includes a memory and a processor that executes at least one instruction from the memory, the at least one instruction including an instruction for measuring a voltage value at at least one point in the battery protection circuit, and an instruction for comparing the voltage value with a threshold value to diagnose whether or not the switches are damaged, and a source terminal of the first switch and a source terminal of the second switch are commonly grounded.

[0033] Here, the first switch may be a discharge control transistor that controls a discharge circuit when the battery pack is discharged, and the second switch may be a charge control transistor that controls a charge circuit when the battery pack is charged.

[0034] The battery protection circuit may further include a voltage application circuit having one end connected to a first point between the battery pack and a drain terminal of the first switch and another end connected to a second point between the drain terminal of the second switch and the load, bypassing the first switch and the second switch and applying a voltage of the battery pack to the second point.

[0035] In this case, the voltage application circuit may be a switching circuit configured with a P-channel.

[0036] Meanwhile, the command for measuring a voltage value at at least one point in the battery protection circuit may include a command for measuring a voltage value at a first point between the battery pack and a Drain terminal of the first switch, a command for measuring a voltage value at a second point between a Drain terminal of the second switch and the load, and a command for measuring a voltage value at a third point where a source of the first switch and a source of the second switch are commonly grounded.

[0037] In addition, a command to diagnose whether the switch is damaged by comparing the voltage value with a threshold value can determine that the first switch and the second switch are operating normally if the voltage value at the first point and the voltage value at the second point are greater than or equal to a threshold value and the voltage value at the third point is less than or equal to the threshold value.

[0038] In addition, the command to diagnose whether the switch is damaged by comparing the voltage value with a threshold value may determine that the first switch and the second switch are operating normally if the voltage value at the third point is equal to or lower than the threshold value.

[0039] Meanwhile, a command for diagnosing whether the switch is damaged by comparing the voltage value with a threshold value may determine that one of the first switch and the second switch is damaged if the voltage value at the first point or the voltage value at the third point is equal to or greater than a threshold value.

[0040] Also, the first switch and the second switch may be high side type power transistors located near the battery pack with respect to the load. Effect of the Invention

[0041] According to an embodiment of the present invention, there is provided an apparatus and method for diagnosing switch damage in a battery protection circuit, and a battery management device including the same, comprising: a battery protection circuit including one or more battery packs and a switch connected to a positive electrode of the battery pack, and protecting the battery pack from overcharging and overdischarging; and a switch damage diagnosis device including a first switch and a second switch provided as power transistors, measuring a voltage value at at least one point in the battery protection circuit and diagnosing whether or not one of the first switch and the second switch is damaged. Since a source terminal of the first switch and a source terminal of the second switch are commonly grounded, it is possible to diagnose whether or not the switch is damaged by only measuring a voltage at a specific point without measuring a current, and it is possible to charge and discharge the battery pack after checking whether or not the switch is damaged. Thus, it is possible to provide an apparatus and method for diagnosing switch damage in a battery protection circuit, and a battery management device including the same, which provide a highly stable, highly accurate and highly reliable communication environment that protects the battery pack from abnormal current generation due to overcharging or overdischarging. [Brief description of the drawings]

[0042] [Figure 1] 1 shows the structure of a battery system to which the present invention can be applied. [Diagram 2] 1 is a portion of a battery protection circuit diagram in a typical battery management device. [Diagram 3] 2 is a partial diagram of a battery protection circuit in a battery management device according to an embodiment of the present invention. [Figure 4] 1 is a block diagram of a switch damage diagnosis device according to an embodiment of the present invention. [Diagram 5] FIG. 4 is a flow chart for explaining a switch damage diagnosis method according to an embodiment of the present invention. [Figure 6] 1 is a table summarizing switch states according to voltage measurements at first to third points in a battery protection circuit according to an experimental example of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0043] Since the present invention can be modified in various ways and has various embodiments, specific embodiments will be illustrated in the drawings and described in detail in the detailed description. However, it is understood that this is not intended to limit the present invention to the specific embodiment, but includes all modifications, equivalents, and alternatives within the spirit and technical scope of the present invention. Similar reference numerals are used for similar components while describing each drawing.

[0044] Terms such as first, second, A, B, etc. may be used to describe various components, but the components should not be limited by these terms. The terms are used only to distinguish one component from another. For example, a first component may be named a second component, and similarly, a second component may be named a first component, without departing from the scope of the present invention. The term "and / or" includes a combination of multiple associated listed items or any of multiple associated listed items.

[0045] When a component is referred to as being "coupled" or "connected" to another component, it should be understood that the component may be directly coupled or connected to the other component, but that there may be other components in between. In contrast, when a component is referred to as being "directly coupled" or "directly connected" to another component, it should be understood that there are no other components in between.

[0046] The terms used in this application are merely used to describe certain embodiments and are not intended to limit the present invention. A singular expression includes a plural expression unless the context clearly indicates otherwise. In this application, the terms "include" or "have" are intended to specify the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, and are not intended to preclude the presence or additional possibility of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0047] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the present invention belongs. Terms as defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning they have in the context of the relevant art, and should not be interpreted as having an ideal or overly formal meaning unless expressly defined in this application.

[0048] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0049] FIG. 1 shows the structure of a battery system to which the present invention can be applied.

[0050] Referring to FIG. 1, a battery pack or a battery module may be configured to include a plurality of connected battery cells. The battery cells or modules may be connected to a load via positive and negative terminals to perform charging and / or discharging operations. The most commonly used battery cells are lithium-ion (Li-Ion) battery cells.

[0051] Such a battery module or battery pack may be provided with a battery management system (BMS).

[0052] A battery management system (BMS) monitors the current, voltage, and temperature of each battery pack under its management, and calculates the SOC (Status Of Charge) based on the monitoring results to control charging and discharging. Here, SOC (State of Charge) is the current charged state of a battery expressed as a percentage [%], and SOH (State of Health) is the current deterioration state of a battery expressed as a percentage [%].

[0053] In this way, the battery management system (BMS) can monitor the battery cells, read the cell voltage, and communicate it to other systems connected to the battery.

[0054] In addition, the battery management system (BMS) balances the charge of the battery cells evenly to extend the life of the battery system.

[0055] To perform such operations, the battery management system (BMS) may include various components such as fuses, current sensing elements, thermistors, switches, and balancers, but in most cases, it also includes an MCU (Micro Controller Unit) or BMIC (Battery Monitoring Integrated Chip) to interface with and control these components.

[0056] In this case, the BMIC may be an IC-type component that is located inside a battery management system (BMS) and measures information such as the voltage, temperature, and current of a battery cell / module. According to an embodiment, the battery management system (BMS) may include a battery protection circuit for cutting off a charge / discharge circuit.

[0057] The battery management system (BMS) can also monitor the battery cells to read the cell voltages and transmit the cell voltages to other systems connected to the battery. To this end, the battery management system (BMS) can include a communication module for communicating with other systems within the device in which the battery system is included.

[0058] The communication modules of the battery management system (BMS) can communicate with other systems in the system using a Controller Area Network (CAN), in which components, modules or systems in the battery management system (BMS) are connected to each other via a CAN bus.

[0059] CAN (Controller Area Network) is a communications standard designed to allow microcontrollers and devices to communicate with each other within a vehicle without the need for a host computer.

[0060] According to an embodiment, CAN communication may be a non-host bus type message-based network protocol that is primarily used for communication between controllers.

[0061] FIG. 2 is a diagram of a portion of a battery protection circuit in a typical battery management device.

[0062] Referring to FIG. 2, the battery protection circuit in the battery management device may be a circuit for cutting off a charging / discharging circuit.

[0063] The battery protection circuit is a circuit that is composed of one or more battery packs and a switch, and can control the operation of the switch to cut off the charge / discharge circuit when an abnormal current occurs in the circuit due to the external environment, thereby preventing the battery pack from being overcharged or overdischarged due to the abnormal current.

[0064] To explain the battery protection circuit in more detail by configuration, the switch can be provided as a power transistor (FET) that performs charge control and discharge control.

[0065] The switches in a typical battery protection circuit may include a charge control transistor (CFET) and a discharge control transistor (DFET).

[0066] In the conventional charge control transistor (CFET), a source terminal is connected to the positive electrode of a battery cell, and a drain terminal is connected to a drain terminal of a discharge control transistor (DFET). In other words, the conventional charge control transistor (CFET) and the discharge control transistor (DFET) are provided in a common drain form in which the drains are commonly grounded.

[0067] Further, the source terminal of the conventional discharge control transistor (DFET) is provided connected to an external input / output side, in other words, a load.

[0068] The operation of the switch can be controlled by voltage values ​​(High Voltage Sensing; HV Sensing) measured at a first point and a second point in the battery protection circuit.

[0069] Here, the voltage value measured at the first point is the voltage value (V B+ ), and the voltage value measured at the second point may be the voltage value (V P+) may be.

[0070] However, in conventional battery protection circuits, the accuracy of the measured voltage of the battery pack to control the switch operation is reduced due to the characteristics of the parasitic diode that occurs inside the power transistor, which reduces the reliability of the charge / discharge control operation.

[0071] Therefore, in the past, in order to precisely control the charging and discharging operation of the switches in the battery protection circuit, the current was measured when the voltage was measured at the first and second points to diagnose whether the first and second switches were damaged.

[0072] However, the conventional switch damage diagnosis device has a drawback in that it is difficult to prevent damage to the battery pack when an abnormal current is applied because the conventional switch damage diagnosis device can measure current only when the battery pack is being charged or discharged.

[0073] Therefore, the present invention describes a highly stable, highly accurate and highly reliable switch damage diagnosis device and method that can diagnose whether or not a switch is damaged in a battery protection circuit simply by measuring the voltage even when no charge / discharge current is flowing, as well as a battery management device that includes the same.

[0074] FIG. 3 is a partial diagram of a battery protection circuit in a battery management device according to an embodiment of the present invention.

[0075] Referring to FIG. 3, the battery management system (BMS) may include a battery protection circuit and a switch damage diagnosis device.

[0076] To explain each configuration in more detail, the battery protection circuit may be configured by connecting one or more battery packs B and a switch S. Thus, in the battery protection circuit, the flow of charge / discharge current of the battery pack B may be controlled by the operation of the switch S.

[0077] Here, the switch S may include a first switch S1 and a second switch S2.

[0078] Also, the first switch S1 and the second switch S2 may be provided as high-side power transistors, i.e., the first switch S1 and the second switch S2 may be located close to the battery pack relative to the load.

[0079] To explain more specifically by way of an embodiment, the first switch S1 may be a discharge control transistor (DFET) that controls battery discharge.

[0080] The drain terminal of the first switch S1 may be connected to the positive electrode of the battery pack, and the source terminal may be connected to the source terminal of the second switch S2, which will be described later.

[0081] Additionally, the second switch S2 may be a charge control transistor (CFET) that controls battery charging.

[0082] More specifically, the drain terminal of the second switch S2 can be connected to the external input / output side, and as described above, the source terminal of the second switch S2 can be connected to the source terminal of the first switch S1.

[0083] In other words, the battery protection circuit in the battery management device according to an embodiment of the present invention may be provided by sequentially connecting one or more battery packs, a first switch S1 and a second switch S2, and the switches S may be provided in a form in which the source terminal of the first switch S1 and the source terminal of the second switch S2 are commonly grounded (Common Source).

[0084] The battery protection circuit may further include a voltage application circuit C connecting the first point (P1) and the second point (P2). Here, the voltage value measured at the first point (P1) is a voltage value (VB+ ), and the voltage value measured at the second point (P2) may be a voltage value (V P+ ) may be.

[0085] Also, the voltage application circuit C may be a basic switching circuit configured with a P channel and without a separate driving driver.

[0086] The voltage application circuit C may be a circuit for applying a battery voltage to the second switch S2 when the second switch S2 is diagnosed by a switch damage diagnosis device described later. In other words, the voltage application circuit C may be a circuit for transmitting a battery voltage at a first point (P1) to a second point (P2) in order to diagnose whether the second switch S2 is damaged. A method for diagnosing whether the second switch S2 is damaged using the voltage application circuit C will be described in more detail with reference to Figures 5 and 6 below.

[0087] The switch damage diagnosis device measures voltage values ​​(High Voltage Sensing; HV Sensing) at first to third points (P1-P3) in the battery protection circuit to diagnose whether the switch is damaged.

[0088] More specifically, the switch damage diagnosis device can measure voltage values ​​(HV Sensing) measured at first to third points (P1-P3).

[0089] Here, the voltage value measured at the first point (P1) is a voltage value (V B+ ), and the voltage value measured at the second point (P2) may be a voltage value (V P+ ) may be.

[0090] The voltage value measured at the third point (P3) is a voltage value (V FET ) may be.

[0091] Thereafter, the switch damage diagnosis device can diagnose whether or not at least one of the first switch S1 and the second switch S2 is damaged based on the measured at least one voltage value.

[0092] According to one embodiment, the switch damage diagnosis device measures a voltage value (V B+ ) and the voltage value (V P+ ) is equal to or greater than the threshold value, and the voltage value (V FET ) is equal to or less than the threshold value, it can be determined that the first switch S1 and the second switch S2 operate normally.

[0093] According to another embodiment, the switch damage diagnosis device detects the voltage value at the first point to the voltage value (V B+ , V P+ , V FET ) is equal to or greater than the threshold, it can be determined that one of the first switch S1 and the second switch S2 is damaged.

[0094] Therefore, the switch damage diagnosis device in a battery management device according to an embodiment of the present invention can diagnose whether or not a switch in a battery protection circuit is damaged without a separate current measurement, thereby preventing damage to a battery pack caused by a parasitic diode.

[0095] The switch damage diagnosis device will be described in more detail below by hardware configuration in FIG.

[0096] FIG. 4 is a block diagram of a switch damage diagnosis device according to an embodiment of the present invention.

[0097] Referring to FIG. 4, the switch damage diagnosis device can be provided in the form of a Micro Controller Unit (MCU) in a battery management system (BMS).

[0098] To explain the configuration in more detail, the switch damage diagnosis device may include a memory 100 and a processor 200 .

[0099] More specifically, the memory 100 is a space for storing at least one piece of data and may be composed of at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory 100 may be composed of at least one of a read only memory (ROM) and a random access memory (RAM).

[0100] The memory 100 may then contain at least one instruction executed by the processor 200, described below, to diagnose damage to a switch in the battery protection circuit.

[0101] According to an embodiment, the at least one instruction may include instructions for measuring a voltage value at at least one point in the battery protection circuit, and instructions for comparing the measured voltage value to a threshold value to diagnose whether the switch is damaged.

[0102] The processor 200 may represent a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to embodiments of the present invention are performed.

[0103] The processor 200 is capable of repeatedly executing at least one program command stored in the memory 100, as described above.

[0104] The battery management device including the battery protection circuit and the switch damage diagnosis device according to the embodiment of the present invention has been described above.

[0105] A switch damage diagnosis method of the switch damage diagnosis device using the above-mentioned battery protection circuit will be described below.

[0106] FIG. 5 is a flow chart for explaining a switch damage diagnosis method according to an embodiment of the present invention.

[0107] Referring to FIG. 5, the processor 200 may measure a voltage value (HV Sensing) at at least one point in the battery protection circuit device (S1000).

[0108] According to an embodiment, the processor 200 calculates the voltage values ​​(V B+ , V P+ , V FET ) can be measured.

[0109] The processor 200 then calculates the measured voltage value (V B+ , V P+ , V FET ) can be used to determine whether the switch in the battery protection circuit device is damaged (S2000).

[0110] According to one embodiment, the measured voltage value (V B+ , V P+ , V FET ) with the thresholds individually, and B+ , V P+ , V FET ) is equal to or lower than the threshold (Low), the processor 200 can determine that both the first switch S1 and the second switch S2 are operating normally.

[0111] According to another embodiment, the measured voltage value (V B+ , V P+ , V FET ) with the thresholds individually, and B+ , V P+ , V FET) is equal to or greater than the threshold (High), the processor 200 can determine that damage has occurred to at least one of the first switch S1 and the second switch S2.

[0112] An experimental example for determining the states of the first to third switches according to the measured voltage values ​​at the first to third points will be described in more detail with reference to FIG.

[0113] FIG. 6 is a table summarizing the states of the switches according to the voltage measurements at the first to third points in a battery protection circuit according to an experimental example of the present invention.

[0114] Referring to FIG. 6, the switch damage diagnosis device detects voltages (V B+ , V P+ , V FET ) can be measured to diagnose switch damage.

[0115] In one experimental example, the voltage values ​​at the first to third points (P1-P3) were measured depending on whether the first switch S1 and the second switch S2 were damaged. When the first switch S1 and the second switch S2 were in a normal state and the circuit was cut off (open), the voltage value (V B+ ) and the voltage value (V P+ ) is measured to be equal to or greater than a certain threshold voltage value (High), and the voltage measurement at a third point (P3) (V FET ) was measured to be below a certain threshold voltage (Low).

[0116] Meanwhile, according to another experimental example, when the first switch S1 is damaged and shorted (Short), and the second switch S2 operates normally and breaks the circuit (Open), the voltage value (V B+ , V P+ , V FET ) was measured to be above a certain threshold voltage value (High).

[0117] In another embodiment, when the first switch S1 is in a normal state and the second switch S2 is damaged and shorted, the voltage values ​​(V B+ , V P+ , V FET ) was measured to be above a certain threshold voltage value (High).

[0118] Meanwhile, in another embodiment, when both the discharge control transistor (DFET) and the charge control transistor (CFET) are damaged and shorted, the voltage values ​​(V B+ , V P+ , V FET ) was measured to be above a certain threshold voltage value (High).

[0119] In other words, the switch damage diagnosis device according to the embodiment of the present invention detects the voltage measurement value (V FET ) is equal to or lower than the threshold voltage (Low), it can be confirmed that both the first switch S1 and the second switch S2 operate normally.

[0120] Therefore, without being limited to the above, the switch damage diagnosis device according to the embodiment of the present invention can detect the voltage value (V FET ) and comparing it with a threshold voltage, it is also possible to determine whether the first switch S1 and the second switch S2 are damaged or not.

[0121] To summarize the above, in the past, in order to diagnose damage to a switch in a battery protection circuit device, it was necessary to charge or discharge the battery cell. However, the battery protection circuit device of the embodiment of the present invention can diagnose whether or not the switch is damaged simply by measuring the voltage at at least one point, and can charge or discharge the battery cell after checking whether or not the switch is damaged, thereby protecting the battery pack from abnormal current generation due to overcharging or over-discharging.

[0122] The above describes the device and method for diagnosing switch damage in a battery protection circuit and the battery management device including the same according to the embodiment of the present invention.

[0123] According to an embodiment of the present invention, there is provided an apparatus and method for diagnosing switch damage in a battery protection circuit, and a battery management device including the same, comprising: a battery protection circuit including one or more battery packs and a switch connected to a positive electrode of the battery pack, and protecting the battery pack from overcharging and overdischarging; and a switch damage diagnosis device including a first switch and a second switch provided as power transistors, measuring a voltage value at at least one point in the battery protection circuit and diagnosing whether or not one of the first switch and the second switch is damaged. Since a source terminal of the first switch and a source terminal of the second switch are commonly grounded, it is possible to diagnose whether or not the switch is damaged only by measuring a voltage at a specific point without measuring a current, and it is possible to charge and discharge the battery pack after checking whether or not the switch is damaged. Thus, it is possible to provide an apparatus and method for diagnosing switch damage in a battery protection circuit, and a battery management device including the same, which provide a highly stable and reliable communication environment that protects the battery pack from abnormal current generation due to overcharging or overdischarging.

[0124] The operation of the method according to the embodiment of the present invention can be embodied as a computer readable program or code in a computer readable recording medium. The computer readable recording medium includes all kinds of recording devices in which data that can be read by a computer system is stored. In addition, the computer readable recording medium can be distributed to computer systems connected via a network, and the computer readable program or code can be stored and executed in a distributed manner.

[0125] Additionally, the computer readable recording medium may include a hardware device specially configured to store and execute program instructions, such as a ROM, a RAM, a flash memory, etc. The program instructions may include not only machine code, such as produced by a compiler, but also high-level language code that can be executed by a computer using an interpreter, etc.

[0126] Some aspects of the invention have been described in the context of an apparatus, but it may also be presented in terms of a corresponding method, where a block or apparatus corresponds to a method step or a feature of a method step. Similarly, aspects described in the context of a method may be presented in terms of a corresponding block or item or feature of a corresponding apparatus. Some or all of the method steps may be performed by (or using) a hardware apparatus, such as, for example, a microprocessor, a programmable computer, or an electronic circuit. In some embodiments, one or more of the most important method steps may be performed by such an apparatus.

[0127] Although the present invention has been described with reference to preferred embodiments thereof, those skilled in the art will understand that various modifications and variations of the present invention can be made without departing from the spirit and scope of the present invention as set forth in the following claims. [Explanation of symbols]

[0128] B: Battery cell C: Voltage application circuit S: Switch S1: First switch (DFET) S2: Second switch (CFET) P1: First point P2: Second point P3: The third point 100:Memory 200: Processor

Claims

1. In the battery management device, a battery protection circuit including a first switch and a second switch connected to the battery pack; a switch damage diagnosis device for diagnosing whether or not one of the first switch and the second switch is damaged by measuring a voltage value at at least one point in the battery protection circuit; Including, A drain terminal of the first switch is connected to a positive electrode of the battery pack, A drain terminal of the second switch is connected to a load; A source terminal of the first switch and a source terminal of the second switch are commonly grounded (Common Source); the battery protection circuit further includes a voltage application circuit having one end connected to a first point between the battery pack and a drain terminal of the first switch and another end connected to a second point between a drain terminal of the second switch and the load, bypassing the first switch and the second switch and applying a voltage of the battery pack to the second point. Battery management device.

2. the first switch is a discharge control transistor that controls a discharge circuit when the battery pack is discharged; 2. The battery management device according to claim 1, wherein the second switch is a charge control transistor that controls a charging circuit when the battery pack is being charged.

3. 2. The battery management device according to claim 1, wherein the voltage application circuit is a switching circuit configured with a P-channel.

4. The at least one location is a first point between the battery pack and a drain terminal of the first switch; a second point between a drain terminal of the second switch and the load; a third point where the source of the first switch and the source of the second switch are commonly grounded; The battery management device of claim 1 .

5. The switch damage diagnosis device includes: The battery management device according to claim 4 , wherein when the voltage value at the third point is equal to or lower than a threshold value, it is determined that the first switch and the second switch operate normally.

6. The switch damage diagnosis device includes:

5. The battery management device of claim 4, wherein when the voltage value at the first point and the voltage value at the second point are greater than or equal to a threshold value and the voltage value at the third point is less than or equal to a threshold value, it is determined that the first switch and the second switch are operating normally.

7. The switch damage diagnosis device includes:

5. The battery management device of claim 4, further comprising: a voltage control circuit for determining whether one of the first switch and the second switch is damaged when the voltage value at the first point or the voltage value at the third point is equal to or greater than a threshold value.

8. A method for diagnosing whether or not a first switch and a second switch connected to a battery pack are damaged in a battery protection circuit including the first switch and the second switch, the method comprising: measuring a voltage value at at least one point within the battery protection circuit; comparing the voltage value with a threshold value to diagnose whether or not any one of the first switch and the second switch is damaged; Including, A source terminal of the first switch and a source terminal of the second switch are commonly grounded (Common Source), the battery protection circuit further includes a voltage application circuit having one end connected to a first point between the battery pack and a Drain terminal of the first switch and another end connected to a second point between a Drain terminal of the second switch and a load, bypassing the first switch and the second switch and applying a voltage of the battery pack to the second point.

9. the first switch is a discharge control transistor that controls a discharge circuit when the battery pack is discharged; 9. The switch damage diagnosis method according to claim 8, wherein the second switch is a charge control transistor that controls a charging circuit when the battery pack is charged.

10. 9. The switch damage diagnosis method according to claim 8, wherein the voltage application circuit is a switching circuit configured with a P-channel.

11. The step of measuring a voltage value at at least one point within the battery protection circuit comprises: measuring a voltage value at the first point between the battery pack and a drain terminal of the first switch; measuring a voltage value at the second point between a drain terminal of the second switch and the load; measuring a voltage value at a third point where the source of the first switch and the source of the second switch are commonly grounded; The switch damage diagnosis method of claim 8, comprising:

12. The step of comparing the voltage value with a threshold value to diagnose whether or not any one of the first switch and the second switch is damaged includes: The switch damage diagnosis method of claim 11, further comprising the step of determining that the first switch and the second switch operate normally if the voltage value at the third point is equal to or less than a threshold value.

13. The step of comparing the voltage value with a threshold value to diagnose whether or not any one of the first switch and the second switch is damaged includes:

12. The switch damage diagnosis method of claim 11, further comprising: determining that the first switch and the second switch operate normally when the voltage value at the first point and the voltage value at the second point are equal to or greater than a threshold value and the voltage value at the third point is equal to or less than a threshold value.

14. The step of comparing the voltage value with a threshold value to diagnose whether or not any one of the first switch and the second switch is damaged includes:

12. The switch damage diagnosis method of claim 11, further comprising the step of determining that one of the first switch and the second switch is damaged when the voltage value at the first point or the voltage value at the third point is equal to or greater than a threshold value.

15. The first switch and the second switch are 9. The switch damage diagnosis method of claim 8, wherein the load is a high side type power transistor located closer to the battery pack than the load.

16. 1. An apparatus for diagnosing whether or not a first switch and a second switch connected to a battery pack are damaged in a battery protection circuit including the first switch and the second switch, Memory, a processor for executing at least one instruction of said memory; Including, The at least one instruction: instructions for measuring a voltage value at at least one point within the battery protection circuit; instructions for diagnosing whether any one of the first switch and the second switch is damaged by comparing the voltage value with a threshold value; Including, A source terminal of the first switch and a source terminal of the second switch are commonly grounded (Common Source), The battery protection circuit includes: One end of the switch is connected to a first point between the battery pack and a drain terminal of the first switch, and the other end of the switch is connected to a second point between the drain terminal of the second switch and a load, a voltage application circuit that applies a voltage of the battery pack to the second point, bypassing the first switch and the second switch; Switch damage diagnostic device.

17. the first switch is a discharge control transistor that controls a discharge circuit when the battery pack is discharged; 17. The switch damage diagnosis device according to claim 16, wherein the second switch is a charge control transistor that controls a charging circuit when the battery pack is being charged.

18. 17. The switch damage diagnosis device according to claim 16, wherein the voltage application circuit is a switching circuit configured with a P-channel.

19. The instructions for measuring a voltage value at at least one point within the battery protection circuit include: instructions for measuring a voltage value at a first point between the battery pack and a drain terminal of the first switch; instructions for measuring a voltage value at a second point between a Drain terminal of the second switch and the load; a command to measure a voltage value at a third point where a source of the first switch and a source of the second switch are commonly grounded; The switch damage diagnosis apparatus of claim 16, comprising:

20. The instructions for diagnosing whether or not one of the first switch and the second switch is damaged by comparing the voltage value with a threshold value include:

20. The switch damage diagnosis apparatus of claim 19, further comprising instructions for determining that the first switch and the second switch are operating normally if the voltage value at the first point and the voltage value at the second point are greater than or equal to a threshold value and the voltage value at the third point is less than or equal to a threshold value.

21. The instructions for diagnosing whether or not one of the first switch and the second switch is damaged by comparing the voltage value with a threshold value include:

20. The switch damage diagnosis apparatus of claim 19, further comprising instructions for determining that the first switch and the second switch are operating normally if the voltage value at the third point is equal to or less than a threshold value.

22. The instructions for diagnosing whether or not one of the first switch and the second switch is damaged by comparing the voltage value with a threshold value include:

20. The switch damage diagnosis device of claim 19, further comprising instructions for determining that one of the first switch and the second switch is damaged if the voltage value at the first point or the voltage value at the third point is equal to or greater than a threshold value.

23. The first switch and the second switch are 17. The switch damage diagnosis apparatus of claim 16, wherein the load is a high side type power transistor located closer to the battery pack than the load.

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