Battery pack and current sensor diagnostic method

Abstract

Disclosed are a battery pack and a current sensor diagnosis method capable of diagnosing an abnormality of a current sensor including an off resistor. The battery pack includes: a battery module including a plurality of battery cells; the current sensor is used for measuring current in the battery module; a first switch connected to a current path between the cathode (B +) of the battery module and the first group of terminals (P +); a second switch connected to a current path between the anode (B-) of the battery module and the second group of terminals (P-); first to third temperature sensors that measure a shunt temperature of the current sensor, a first switching temperature of the first switch, and a second switching temperature of the second switch, respectively; and a processor that diagnoses the current sensor based on at least one of the shunt temperature, the first switching temperature, and the second switching temperature.

Description

Technical Field

[0001] The present invention relates to a battery pack and a current sensor diagnosis method capable of diagnosing abnormality of a current sensor including a shunt resistor. Background Art

[0002] With the rapidly growing demand for portable electronic products (such as laptops, cameras and mobile phones) and the development of electric vehicles, energy storage batteries, robots, satellites, etc., active research has been conducted on the development of high-performance secondary batteries (hereinafter referred to as batteries) that can be repeatedly charged and discharged.

[0003] Typically, a power supply system of a battery may be provided with a current sensor to measure current. The current sensor measures the current flowing along the charge / discharge path of the battery to monitor the state of the battery, detect overcurrent in the battery, etc. The current measured by the current sensor may be used as information for calculating the SOC (state of charge) of the battery or as a basis for determining whether the charge / discharge process is proceeding normally, etc.

[0004] A shunt resistor can be used as a component for measuring the current flowing through a battery, and the current can be measured by measuring the voltage across the shunt resistor. However, if the shunt resistor does not work properly, the current flowing through the battery cannot be measured correctly. As a result, even when an abnormal situation (such as overcurrent, etc.) occurs, the shunt resistor cannot properly block the overcurrent, resulting in serious problems such as battery failure or explosion.

[0005] This section is intended only to provide a better understanding of the background of the invention and therefore may contain information that is not necessarily prior art. Summary of the invention

[0006] One aspect of the present invention is to provide a battery pack and a current sensor diagnosis method capable of diagnosing abnormality of a current sensor including a shunt resistor.

[0007] The above and other aspects and features of the present invention will become apparent from the following description of embodiments of the present invention.

[0008] According to an aspect of the present invention, a battery pack diagnoses a current sensor based on at least one of a shunt temperature measured at a shunt resistor, a first switch temperature measured at a first switch, and a second switch temperature measured at a second switch.

[0009] According to the present invention, a battery pack and a current sensor diagnosis method can detect an abnormality (failure, defect) of a shunt resistor, thereby enabling accurate detection of an overcurrent by diagnosing an abnormality of a current sensor including a shunt resistor.

[0010] According to the present invention, a battery pack and a current sensor diagnosis method can prevent problems such as battery failure and explosion due to abnormality (error, malfunction) of a shunt resistor.

[0011] According to the present invention, the battery pack and current sensor diagnostic method can detect the abnormality (fault, defect) of the shunt resistor, and can reduce the risk caused by the abnormality of the shunt resistor by changing the abnormality of the shunt resistor from a single-point fault to a double-point fault.

[0012] However, aspects and features of the present invention are not limited to the above-mentioned contents, and other aspects and features not mentioned will be clearly understood by those skilled in the art from the detailed description given below. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The following drawings attached to this specification illustrate embodiments of the present disclosure and, together with the detailed description of the present disclosure, further describe aspects and features of the present disclosure. Therefore, the present disclosure should not be interpreted as being limited to the drawings:

[0014] Figure 1 is a block diagram of the battery pack;

[0015] Figure 2 It is the circuit diagram of the battery pack;

[0016] Figure 3 is a flow chart showing a current sensor diagnostic method according to one embodiment of the present invention; and

[0017] Figure 4 is a flow chart showing a current sensor diagnosis method according to another embodiment of the present invention. DETAILED DESCRIPTION

[0018] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The terms or words used in this specification and claims should not be interpreted as limited to the usual or dictionary meanings, but should be interpreted as meanings and concepts consistent with the technical ideas of the present disclosure, with the principle that the inventor can be his / her own lexicon compiler to appropriately define the concept of the term to best explain his / her invention.

[0019] The embodiments described in this specification and the configurations shown in the drawings are only some embodiments of the present disclosure and do not represent all technical ideas, aspects and features of the present disclosure. Therefore, it should be understood that when submitting this application, there may be various equivalents and modifications to replace or modify the embodiments described herein.

[0020] It should be understood that when an element or layer is referred to as being "on," "connected to," or "coupled to" another element or layer, it may be directly on, connected to, or coupled to another element or layer, or one or more intervening elements or layers may be present. When an element or layer is referred to as being "directly on," "directly connected to," or "directly coupled to" another element or layer, there may be no intervening elements or layers. For example, when a first element is described as being "coupled" or "connected to" a second element, the first element may be directly coupled or connected to the second element, or the first element may be indirectly coupled or connected to the second element via one or more intervening elements.

[0021] In the accompanying drawings, the sizes of various elements, layers, etc. may be exaggerated for clarity of illustration. The same reference numerals represent the same elements. As used herein, the term "and / or" includes any and all combinations of one or more related listed items. In addition, "may" is used to relate to "one or more embodiments of the present disclosure" when describing the embodiments of the present disclosure. Statements such as "at least one" and "any one" modify the entire element list when they are in front of the element list, without modifying the individual elements of the list. When phrases such as "at least one of A, B and C", "at least one of A, B or C", "at least one selected from the group of A, B and C" or "at least one selected from A, B and C" are used to specify the list of elements A, B and C, the phrase may refer to any and all suitable combinations or subsets of A, B and C, such as A, B, C, A and B, A and C, B and C, or A and B and C. As used herein, the terms "use", "being in use" and "used" may be considered to be synonymous with the terms "utilize", "being utilized" and "utilized", respectively. As used herein, the terms "substantially," "approximately," and similar terms are used as terms of approximation rather than terms of degree, and are intended to account for the inherent variations in measured or calculated values ​​that those of ordinary skill in the art would recognize.

[0022] It should be understood that although the terms first, second, third, etc. can be used to describe various elements, components, regions, layers and / or parts herein, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are used to distinguish an element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teaching of the exemplary embodiments, the first element, component, region, layer or part discussed below can be referred to as a second element, component, region, layer or part.

[0023] For ease of description, spatially relative terms such as "below", "below", "lower", "above", "upper", etc. may be used herein to describe the relationship between an element or feature and another element or feature shown in the figures. It should be understood that, in addition to the directions described in the accompanying drawings, spatially relative terms are intended to include different orientations of the device in use or operation. For example, if the device in the figure is flipped, the elements described as being "below" or "below" other elements or features will be oriented "above" or "above" other elements or features. Therefore, the term "below" can include directions above and below. The device can be oriented in other ways (rotated 90 degrees or in other directions), and the spatially relative descriptors used herein should be interpreted accordingly.

[0024] The terms used herein are intended to describe embodiments of the present disclosure, rather than to limit the present disclosure. As used herein, the singular forms "one" and "an" are also intended to include plural forms, unless the context clearly indicates otherwise. It will also be understood that the terms "include", "including ...", "comprising" and / or "comprising ..." when used in this specification specify the presence of stated features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0025] In addition, any numerical range disclosed and / or cited herein is intended to include all subranges of the same numerical precision contained in the cited range. For example, the range of "1.0 to 10.0" is intended to include all subranges between the listed minimum value 1.0 and the listed maximum value 10.0 (including these two values), that is, the minimum value is equal to or greater than 1.0, and the maximum value is equal to or less than 10.0, such as, for example, 2.4 to 7.6. Any maximum numerical limit listed herein is intended to include all lower numerical limits contained therein, and any minimum numerical limit listed in this specification is intended to include all higher numerical limits contained therein.

[0026] Reference to two compared elements, features, etc., being "the same" may mean that they are "substantially the same." Thus, the phrase "substantially the same" may include situations where the deviation is considered low in the art, such as a deviation of 5% or less. In addition, when a parameter is said to be uniform in a given area, this may mean that it is uniform with respect to the average value.

[0027] Throughout the specification, unless otherwise specified, each element may be in the singular or in the plural.

[0028] When any element is referred to as being disposed (or located or placed) "on (or below)" or "above (or below)" a component, this may mean that the arbitrary element is placed in contact with the upper (or lower) surface of the component, and may also mean that another component may be interposed between the component and any element disposed (or located or placed) above (or below) the component.

[0029] Furthermore, it should be understood that when an element is referred to as being “coupled,” “linked,” or “connected” to another element, the elements may be directly “coupled,” “linked,” or “connected” to each other, or there may be an intermediate element between them through which the element may be “coupled,” “linked,” or “connected” to another element. Furthermore, when a component is referred to as being “electrically coupled” to another component, the component may be directly connected to the other component, or there may be an intermediate component between them so that the component and the other component are indirectly connected to each other.

[0030] Throughout the specification, unless otherwise specified, when "A and / or B" is stated, it means A, B, or A and B. That is, "and / or" includes any or all combinations of the listed multiple items. Unless otherwise specified, when "C to D" is stated, it means C or more and D or less.

[0031] Figure 1 is a block diagram of a battery pack, and Figure 2 This is the circuit diagram of the battery pack.

[0032] Reference Figure 1 and Figure 2 , the battery pack 100 according to one embodiment of the present invention has a structure capable of being electrically connected to an external device 10 through a cathode connection terminal P(+) and an anode connection terminal P(-). When the external device 10 is a load, the battery pack 100 discharges by acting as a power supply to supply power to the load. The external device 10 operating as a load may be, for example, an electronic device, a mobile vehicle, or an energy storage system (ESS). Here, the mobile vehicle may be, for example, an electric vehicle, a hybrid vehicle, or a smart mobile device.

[0033] The battery pack 100 may include at least one battery module 110, a controller 120, a switch component 130, a current sensor 140, a temperature sensor 150, and an interface 160. Obviously, in various embodiments, the battery pack 100 may further include other components.

[0034] The battery module 110 may include a plurality of battery cells and a module housing. The battery module 110 may include a plurality of batteries connected in series or in parallel to each other. Such battery modules 110 may be connected in series or in parallel to each other.

[0035] The battery cells may be stacked and housed in a module housing. The battery cells may include a cathode lead and an anode lead. Depending on the shape of the battery, the battery cells may be round, prismatic, or pouch-type battery cells.

[0036] The battery pack 100 may include a single stack of cells stacked to form a single module instead of a battery module. The cell stack may be accommodated in an accommodation space of a pack case or in an accommodation space partitioned by a frame, a partition wall, or the like.

[0037] The battery cells generate a large amount of heat during charging / discharging. The generated heat may accumulate in the battery cells, thereby accelerating the degradation of the battery cells. Therefore, the battery pack 100 may further include a cooling member to suppress the degradation of the battery cells. The cooling member may be disposed at the lower portion of the accommodation space for accommodating the battery cells. Alternatively, the cooling member may be disposed on the upper portion or side surface thereof depending on the battery pack 100.

[0038] Waste gas generated inside the battery cell due to abnormal operating conditions (also known as thermal runaway or thermal events in the battery cell) may be discharged from the battery cell. The battery pack 100 or the battery module 110 may include an exhaust port, etc. for discharging the waste gas to suppress damage to the battery pack 100 or the module due to the waste gas.

[0039] The interface 160 may include a plurality of terminals for interfacing with the external device 10. The interface 160 may include group terminals P+, P- for supplying power to an external load or receiving power from an external charging device and a communication terminal DATA for communicating with the external device 10.

[0040] The interface 160 is connected to the battery module 110 and can serve as a terminal for charging the battery module 110 when charging through the connection of a charging device (not shown). The interface 160 can serve as a terminal connected to an external load (not shown) to discharge the battery module 110 when discharging. To this end, the interface 160 may include a first group of terminals P+ and a second group of terminals P-. The first group of terminals P+ may be a cathode group terminal connected to the cathode B+ of the battery module 110. The second group of terminals P- may be an anode group terminal connected to the anode B- of the battery module 110. When a charging device is connected to the interface 160, charging from the charging device to the battery module 110 may occur, and when an external load is connected to the interface 160, discharging from the battery module 110 to the external load may occur.

[0041] The switch component 130 may be controlled by the processor 124 to control the electrical connection between the battery module 110 and the external device 10. The switch component 130 may include a first switch 132 connected between the cathode B+ of the battery module 110 and the first terminal P+, and a second switch 134 connected between the anode B- of the battery module 110 and the second terminal P-.

[0042] The switch member 130 may be connected between the battery module 110 and at least one of the pack terminals P+, P− to cut off / allow electrical connection between the battery module 110 and the external device 10 .

[0043] When the first switch 132 and the second switch 134 are turned on, power may be supplied from the battery module 110 to the external device 10 or from the external device 10 to the battery module 110 .

[0044] The first switch 132 and the second switch 134 may be provided in a power line provided as a current path for charging and discharging the battery module 110 .

[0045] The first switch 132 and the second switch 134 may be implemented by any one or a combination of two or more known switching devices (such as relays, transistors, etc.).

[0046] The current sensor 140 may measure the current of the battery module 110. Here, the current sensor 140 may be a shunt type current sensor 140. The current sensor 140 may measure the current between the battery module 110 and the pack terminals P+, P- to obtain the current of the battery module 110, ie, the charging current or the discharging current.

[0047] The current sensor 140 may include a shunt resistor 145. Therefore, the current sensor 140 may measure the current flowing through the shunt resistor 145. The current sensor 140 including the shunt resistor 145 may calculate the current value flowing along the charge / discharge path of the battery module 110 by measuring the voltage value across the shunt resistor 145. That is, since the resistance of the shunt resistor 145 is a known value, when the voltage value across the shunt resistor 145 is obtained, the current sensor 140 may calculate the current value flowing in the shunt resistor 145. Here, the calculated current value may be the current value flowing along the charge / discharge path of the battery module 110.

[0048] The shunt resistor 145 is a current sensing resistor and may be connected in series to a large current path to measure a current (charging current or discharging current) flowing through the large current path.

[0049] The shunt resistor 145 may be connected to a high current path between the cathode B+ and the first terminal P+ of the battery module 110. However, the present invention is not limited thereto, and according to other embodiments, the shunt resistor 145 may be connected to a high current path between the anode B- and the second terminal P- of the battery module 110.

[0050] The temperature sensor 150 may measure the shunt temperature of the current sensor 140, the first switch temperature of the first switch 132, and the second switch temperature of the second switch 134. Therefore, the temperature sensor 150 may include a first temperature sensor 152 provided to the shunt resistor 145, a second temperature sensor 154 provided to the first switch 132, and a third temperature sensor 156 provided to the second switch 134.

[0051] The first temperature sensor 152 may measure the temperature of the shunt resistor 145 and may transmit the measured shunt temperature to the processor 124 .

[0052] The second temperature sensor 154 may measure the temperature of the first switch 132 and may transmit the measured first switch temperature to the processor 124 .

[0053] The third temperature sensor 156 may measure the temperature of the second switch 134 and may transmit the measured second switch temperature to the processor 124 .

[0054] As one example for temperature measurement, such a temperature sensor 150 may be a thermocouple.

[0055] The controller 120 may include a memory 122 and a processor 124. The controller 120 may be included in a battery management system (BMS).

[0056] The memory 122 may store a program (application) used by the processor 124 to diagnose the current sensor 140. In some embodiments, the memory 122 may store instructions for operating the processor 124. In some embodiments, the memory 122 may be built into the processor 124 or connected to the processor 124 via a bus. In some embodiments, the memory 122 storing the table may be a non-volatile memory.

[0057] The processor 124 may control the on / off of the first switch 132 and the second switch 134 that connect the battery module 110 to the external device 10. For example, the processor 124 may turn off / on the first switch 132 and the second switch 134 to block or allow the flow of current supplied from the external charging device to the battery module 110 through the large current path. That is, the processor 124 may turn on the first switch 132 and the second switch 134 to allow the battery module 110 to charge or discharge. In addition, the processor 124 may turn off the first switch 132 and the second switch 134 to block the flow of current through the large current path between the battery module 110 and the external device 10.

[0058] When current flows between the battery module 110 and the external device 10 , the current sensor 140 may measure the current flowing between the battery module 110 and the external device 10 .

[0059] In addition, the processor 124 may diagnose abnormality of the current sensor 140 based on at least one of the shunt temperature measured by the first temperature sensor 152 , the first switch temperature measured by the second temperature sensor 154 , and the second switch temperature measured by the third temperature sensor 153 .

[0060] As the resistance value of the shunt resistor 145 increases, the same current flow consumes more energy. More energy consumption may indicate that more heat is generated when the resistance value of the shunt resistor 145 is large than when the resistance value of the shunt resistor 145 is small. In addition, when the shunt resistor 145 is in a normal state and maintains a constant resistance value, the temperatures measured at the shunt resistor 145, the first switch 132, and the second switch 134 may be similar because the current flowing in the first switch 132 and the second switch 134 is constant. However, when there is a problem with the shunt resistor 145, the temperature measured at the first switch 132 and the second switch 134 will not change, while the temperature measured at the shunt resistor 145 will change (that is, the temperature measured at the shunt resistor 145 will become larger or smaller). Therefore, when the temperature values ​​at the first switch 132 and the second switch 134 remain unchanged and only the temperature value at the shunt resistor 145 changes significantly, it can be determined that the resistance value of the shunt resistor 145 has changed instead of the current value.

[0061] Therefore, the processor 124 can determine whether the shunt resistor 145 is abnormal based on the shunt temperature, the first switch temperature, and the second switch temperature. Since the shunt resistor 145 is included in the current sensor 140, the abnormality of the shunt resistor 145 can indicate the abnormality of the current sensor 140. Therefore, the abnormality of the shunt resistor 145 can indicate the abnormality of the current sensor 140.

[0062] Therefore, the processor 124 may diagnose abnormality of the current sensor 140 based on at least one of the shunt temperature, the first switch temperature, and the second switch temperature.

[0063] Next, a method of diagnosing abnormality of current sensor 140 by processor 124 will be described.

[0064] The processor 124 may diagnose an abnormality of the current sensor 140 by comparing at least one of the shunt temperature measured by the first temperature sensor 152, the first switch temperature measured by the second temperature sensor 154, and the second switch temperature measured by the third temperature sensor 156 with at least one of a preset shunt maximum temperature, a first switch maximum temperature, and a second switch maximum temperature. Here, the shunt maximum temperature may be a temperature saturated at the shunt resistor 145 at a maximum current (e.g., 550A), the first switch maximum temperature may be a temperature saturated at the first switch 132 at a maximum current (e.g., 550A), and the second switch temperature may be a temperature saturated at the second switch 134 at a maximum current (e.g., 550A).

[0065] Due to the current change, the temperature measured at the shunt resistor 145, the first switch 132 and the second switch 134 will not exceed the corresponding maximum temperature measured at the maximum current under constant resistance conditions. Therefore, the processor 124 can use the shunt maximum temperature, the first switch maximum temperature and the second switch maximum temperature to determine whether the current sensor 140 is abnormal.

[0066] Specifically, when the shunt temperature is less than or equal to the shunt maximum temperature, the first switch temperature is less than or equal to the first switch maximum temperature, and the second switch temperature is less than or equal to the second switch maximum temperature, the processor 124 may determine that the current sensor 140 is normal.

[0067] When the shunt temperature exceeds the shunt maximum temperature, the first switch temperature is less than or equal to the first switch maximum temperature, and the second switch temperature is less than or equal to the second switch maximum temperature, the processor 124 can determine that the current sensor 140 is abnormal. When the temperature trends of the first switch and the second switch 134 are similar, and only the temperature trend measured at the shunt resistor 145 is different, it can be seen that there is a problem with the shunt resistor 145. Therefore, the processor 124 can determine that when the shunt temperature exceeds the shunt maximum temperature, the first switch temperature is less than or equal to the first switch maximum temperature, and the second switch temperature is less than or equal to the second switch maximum temperature, the processor 124 can determine that the current sensor 140 is abnormal.

[0068] When determining that the current sensor 140 is abnormal, the processor 124 may calculate an average temperature of the shunt temperature, the first switch temperature, and the second switch temperature, and may compare the calculated average temperature with the shunt temperature, the first switch temperature, and the second switch temperature to determine the abnormal type of the current sensor 140. Here, the abnormal type of the current sensor 140 may include a shunt resistance value decrease fault, a shunt resistance value increase fault, and the like.

[0069] Specifically, the processor 124 may determine that a shunt resistance value decrease fault has occurred when the difference between the shunt temperature and the average temperature is negative, the difference between the first switch temperature and the average temperature is positive, and the difference between the second switch temperature and the average temperature is positive.

[0070] When the resistance value of the shunt resistor 145 decreases, a safety problem may occur because the current must be high in order to measure the desired voltage value. For example, when 550A or more is set as an overcurrent, when the current measured by the shunt resistor 145 is 550A or more, the processor 124 must disconnect the first switch 132 and the second switch 134 to cut off the current. However, as the resistance value of the shunt resistor decreases, when the current is in the range of 570A to 580A, the processor 124 may disconnect the first switch 132 and the second switch 134 to cut off the current. In this case, the processor 124 cannot detect the overcurrent (overcurrent detection failure), resulting in a safety problem.

[0071] Processor 124 may determine that a shunt resistance value increase fault has occurred when the difference between the shunt temperature and the average temperature is positive, the difference between the first switch temperature and the average temperature is negative, and the difference between the second switch temperature and the average temperature is negative.

[0072] When the resistance value of the shunt resistor 145 increases, a quality problem may occur because the current must be reduced in order to measure the desired voltage value. For example, when 550A or more is set as an overcurrent, when the current measured by the shunt resistor 145 is 550A or more, the processor 124 must disconnect the first switch 132 and the second switch 134 to cut off the current. However, as the resistance value of the shunt resistor increases, when the current is within the range of 530A to 540A, the processor 124 may disconnect the first switch 132 and the second switch 134 to cut off the current. In this case, although no safety problem occurs, a quality problem may occur.

[0073] According to another embodiment of the present invention, the processor 124 can diagnose the abnormality of the current sensor 140 based on the shunt temperature difference, the first switch temperature difference, and the second switch temperature difference, the shunt temperature difference refers to the absolute value of the difference between the shunt temperature and the shunt saturation temperature, the first switch temperature difference refers to the absolute value of the difference between the first switch temperature and the first switch saturation temperature, and the second switch temperature difference refers to the absolute value of the difference between the second switch temperature and the second switch saturation temperature. To this end, the memory 122 can store a lookup table in which at least one of the shunt saturation temperature, the first switch saturation temperature, and the second switch saturation temperature depending on the current is set. The shunt saturation temperature may refer to the saturation temperature of the shunt resistor 145 at each current, the first switch saturation temperature may refer to the saturation temperature of the first switch 132 at each current, and the second switch saturation temperature may refer to the saturation temperature of the second switch 134 at each current.

[0074] Next, a method of diagnosing abnormality of the current sensor 140 using the shunt temperature difference, the first switching temperature difference, and the second switching temperature difference by the processor 124 will be described.

[0075] The processor 124 may calculate an average value of the current accumulated so far, and obtain the shunt saturation temperature, the first switch saturation temperature, and the second switch saturation temperature corresponding to the calculated average current from the lookup table.

[0076] The processor 124 may then calculate a shunt temperature difference, a first switch temperature difference, and a second switch temperature difference, wherein the shunt temperature difference refers to the absolute value of the difference between the shunt temperature and the shunt saturation temperature, the first switch temperature difference refers to the absolute value of the difference between the first switch temperature and the first switch saturation temperature, and the second switch temperature difference refers to the absolute value of the difference between the second switch temperature and the second switch saturation temperature.

[0077] Then, the processor 124 may compare the shunt temperature difference, the first switch temperature difference, and the second switch temperature difference with a preset reference value to diagnose an abnormality of the current sensor 140. In this case, the reference value may represent (2*error rate of the temperature sensor 150). The error rate of the temperature sensor 150 may be a preset value.

[0078] Specifically, when the shunt temperature difference is less than or equal to the reference value, the first switch temperature difference is less than or equal to the reference value, and the second switch temperature difference is less than or equal to the reference value, the processor 124 may determine that the current sensor 140 is normal.

[0079] When the shunt temperature difference exceeds the reference value, the first switch temperature difference is less than or equal to the reference value, and the second switch temperature difference is less than or equal to the reference value, the processor 124 may determine that the current sensor 140 is abnormal.

[0080] When determining that the current sensor 140 is abnormal, the processor 124 may determine the abnormality type of the current sensor 140 based on the sign of the difference between the shunt temperature and the shunt saturation temperature.

[0081] That is, when the difference between the shunt temperature and the shunt saturation temperature is negative, the processor 124 may determine that a shunt resistance value reduction fault has occurred. Once it is determined that a shunt resistance value reduction fault has occurred, a safety issue may arise.

[0082] When the difference between the shunt temperature and the shunt saturation temperature is positive, the processor 124 may determine that a shunt resistance value increase fault has occurred. Once it is determined that a shunt resistance value increase fault has occurred, although no safety problem occurs, a quality problem may occur.

[0083] When it is determined that the current sensor 140 is abnormal, the processor 124 may turn off the first switch 132 and the second switch 134 to cut off the current.

[0084] The processor 124 may be implemented by a central processing unit (CPU) or a system on chip (SoC), may run an operating system or application to control a plurality of hardware or software components connected to the processor 124, and may perform various data processing and calculations. The processor 124 may be configured to execute at least one instruction stored in the memory 122 and store the data obtained by the execution in the memory 122.

[0085] Figure 3 is a flow chart showing a current sensor diagnosis method according to one embodiment of the present invention.

[0086] refer to Figure 3 , the processor 124 receives the shunt temperature, the first switch temperature, and the second switch temperature transmitted from the first temperature sensor 152, the second temperature sensor 154, and the third temperature sensor 156, respectively (S302). The first temperature sensor 152 provided to the shunt resistor 145 may measure the shunt temperature and transmit it to the processor 124. The second temperature sensor 154 provided to the first switch 132 may measure the first switch temperature and transmit it to the processor 124. The third temperature sensor 156 provided to the second switch 134 may measure the second switch temperature and transmit it to the processor 124.

[0087] After step S302 , the processor 124 determines whether the shunt temperature is less than or equal to the shunt maximum temperature, whether the first switch temperature is less than or equal to the first switch maximum temperature, and whether the second switch temperature is less than or equal to the second switch maximum temperature ( S304 ).

[0088] When it is determined in step S304 that the shunt temperature is less than or equal to the shunt maximum temperature, the first switch temperature is less than or equal to the first switch maximum temperature, and the second switch temperature is less than or equal to the second switch maximum temperature, the processor 124 determines that the current sensor 140 is normal ( S306 ).

[0089] When it is not determined in step S304 that the shunt temperature is less than or equal to the shunt maximum temperature, the first switch temperature is less than or equal to the first switch maximum temperature, and the second switch temperature is less than or equal to the second switch maximum temperature, the processor 124 determines whether the shunt temperature exceeds the shunt maximum temperature, whether the first switch temperature is less than or equal to the first switch maximum temperature, and whether the second switch temperature is less than or equal to the second switch maximum temperature (S308).

[0090] When it is determined in step S308 that the shunt temperature exceeds the shunt maximum temperature, the first switch temperature is less than or equal to the first switch maximum temperature, and the second switch temperature is less than or equal to the second switch maximum temperature, the processor 124 determines that the current sensor 140 is abnormal (S310).

[0091] When it is determined that the current sensor 140 is abnormal, the processor 124 calculates an average temperature of the shunt temperature, the first switch temperature, and the second switch temperature ( S312 ).

[0092] After step S312, the processor 124 compares the calculated average temperature with the shunt temperature, the first switch temperature, and the second switch temperature (S314) to determine the abnormality type of the current sensor 140 (S316). If the difference between the shunt temperature and the average temperature is negative, the difference between the first switch temperature and the average temperature is positive, and the difference between the second switch temperature and the average temperature is positive, the processor 124 can determine that a shunt resistance value decrease fault has occurred. If the difference between the shunt temperature and the average temperature is positive, the difference between the first switch temperature and the average temperature is negative, and the difference between the second switch temperature and the average temperature is negative, the processor 124 can determine that a shunt resistance value increase fault has occurred.

[0093] Figure 4 is a flow chart showing a current sensor diagnosis method according to another embodiment of the present invention.

[0094] Reference Figure 4 , the processor 124 calculates the average value of the current accumulated so far (S402), and obtains the shunt saturation temperature, the first switch saturation temperature, and the second switch saturation temperature corresponding to the calculated average current from the lookup table (S404). Since the lookup table has the shunt saturation temperature, the first switch saturation temperature, and the second switch saturation temperature set according to the current, the processor 124 can obtain the shunt saturation current, the first switch saturation temperature, and the second switch saturation temperature corresponding to the average current from the lookup table.

[0095] After step S404, the processor 124 calculates the shunt temperature difference, the first switch temperature difference, and the second switch temperature difference (S406). Here, the shunt temperature difference may represent the absolute value of the difference between the shunt temperature and the shunt saturation temperature, the first switch temperature difference may represent the absolute value of the difference between the first switch temperature and the first switch saturation temperature, and the second switch temperature difference may represent the absolute value of the difference between the second switch temperature and the second switch saturation temperature.

[0096] After step S406 , the processor 124 determines whether the shunt temperature difference is less than or equal to a reference value, whether the first switch temperature difference is less than or equal to a reference value, and whether the second switch temperature difference is less than or equal to a reference value ( S408 ).

[0097] When it is determined in step S408 that the shunt temperature difference is less than or equal to the reference value, the first switch temperature difference is less than or equal to the reference value, and the second switch temperature difference is less than or equal to the reference value, the processor 124 determines that the current sensor 140 is normal (S410).

[0098] If step S408 is not satisfied, the processor 124 determines whether the shunt temperature difference exceeds a reference value, whether the first switch temperature difference is less than or equal to the reference value, and whether the second switch temperature difference is less than or equal to the reference value (S412).

[0099] When it is determined in step S412 that the shunt temperature difference exceeds the reference value, the first switch temperature difference is less than or equal to the reference value, and the second switch temperature difference is less than or equal to the reference value, the processor 124 determines that the current sensor 140 is abnormal (S414).

[0100] When determining that the current sensor 140 is abnormal, the processor 124 determines the abnormal type of the current sensor 140 based on the sign of the difference between the shunt temperature and the shunt saturation temperature (S416). In this case, if the difference between the shunt temperature and the shunt saturation temperature is negative, the processor 124 can determine that a shunt resistance value decrease fault has occurred. If the difference between the shunt temperature and the shunt saturation temperature is positive, the processor 124 can determine that a shunt resistance value increase fault has occurred.

[0101] As described above, according to the present invention, the battery pack and the current sensor diagnosis method can detect abnormality (error, failure) of the shunt resistor, thereby being able to accurately detect overcurrent by diagnosing abnormality of the current sensor 140 including the shunt resistor.

[0102] According to the present invention, a battery pack and a current sensor diagnosis method can prevent problems such as battery failure and explosion due to abnormality (error, malfunction) of a shunt resistor.

[0103] According to the present invention, the battery pack and current sensor diagnostic method can detect the abnormality (error, failure) of the shunt resistor, and can reduce the risk caused by the abnormality of the shunt resistor by changing the abnormality of the shunt resistor from a single-point failure to a double-point failure.

[0104] The embodiments described herein may be implemented as, for example, a method or process, an apparatus, a software program, a data stream, or a signal. Although discussed in the context of a single type of implementation (e.g., discussed only as a method), the features discussed herein may also be implemented in other forms (e.g., an apparatus or program). The apparatus may be implemented by suitable hardware, software, firmware, etc. The method may be implemented on an apparatus, such as a processor that generally refers to a processing device including a computer, a microprocessor, an integrated circuit, a programmable logic device, etc. The processor includes a communication device, such as a computer, a mobile phone, a personal digital assistant (PDA), and other devices that facilitate information communication between the apparatus and the end user.

[0105] Although the present invention has been described with reference to some embodiments and drawings showing aspects thereof, the present invention is not limited thereto. Those skilled in the art to which the present invention pertains may make various modifications and changes within the technical spirit of the present invention and the scope of the claims and their equivalents.

Claims

1. A battery pack comprising: A battery module, including a plurality of battery cells; Current sensor, measuring the current in the battery module; a first switch connected to a current path between a cathode (B+) of the battery module and a first set of terminals (P+); a second switch connected to a current path between an anode (B-) of the battery module and a second set of terminals (P-); First to third temperature sensors, measuring a shunt temperature of the current sensor, a first switch temperature of the first switch, and a second switch temperature of the second switch, respectively; as well as A processor diagnoses the current sensor based on at least one of the shunt temperature, the first switch temperature, and the second switch temperature.

2. The battery pack according to claim 1, wherein: The current sensor includes a shunt resistor, and the first temperature sensor measures a shunt temperature indicative of a temperature of the shunt resistor.

3. The battery pack according to claim 1, wherein: The processor diagnoses abnormality of the current sensor by comparing at least one of a shunt temperature, a first switch temperature, and a second switch temperature with at least one of a preset shunt maximum temperature, a first switch maximum temperature, and a second switch maximum temperature.

4. The battery pack according to claim 3, wherein: The processor determines that the current sensor is normal when the shunt temperature is less than or equal to the shunt maximum temperature, the first switch temperature is less than or equal to the first switch maximum temperature, and the second switch temperature is less than or equal to the second switch maximum temperature.

5. The battery pack according to claim 3, wherein: The processor determines that the current sensor is abnormal when the shunt temperature exceeds the shunt maximum temperature, the first switch temperature is less than or equal to the first switch maximum temperature, and the second switch temperature is less than or equal to the second switch maximum temperature.

6. The battery pack according to claim 5, wherein: When determining that the current sensor is abnormal, the processor calculates an average temperature of the shunt temperature, the first switch temperature, and the second switch temperature, and compares the calculated average temperature with the shunt temperature, the first switch temperature, and the second switch temperature to determine the abnormality type of the current sensor.

7. The battery pack according to claim 6, wherein: The processor determines that a shunt resistance value decrease fault has occurred when a difference between a shunt temperature and the average temperature is negative, a difference between a first switch temperature and the average temperature is positive, and a difference between a second switch temperature and the average temperature is positive.

8. The battery pack according to claim 6, wherein: The processor determines that a shunt resistance value increase fault has occurred when a difference between a shunt temperature and the average temperature is positive, a difference between a first switch temperature and the average temperature is negative, and a difference between a second switch temperature and the average temperature is negative.

9. The battery pack according to claim 1, further comprising: a lookup table, wherein at least one of the shunt saturation temperature, the first switch saturation temperature, and the second switch saturation temperature is set according to the current, The processor calculates an average value of the current accumulated so far; obtains a shunt saturation temperature, a first switch saturation temperature, and a second switch saturation temperature corresponding to the calculated average current from the lookup table; calculates a shunt temperature difference, a first switch temperature difference, and a second switch temperature difference, wherein the shunt temperature difference refers to an absolute value of a difference between a shunt temperature and a shunt saturation temperature, the first switch temperature difference refers to an absolute value of a difference between a first switch temperature and a first switch saturation temperature, and the second switch temperature difference refers to an absolute value of a difference between a second switch temperature and a second switch saturation temperature; and compares the shunt temperature difference, the first switch temperature difference, and the second switch temperature difference with a preset reference value to diagnose an abnormality of the current sensor.

10. The battery pack according to claim 9, wherein: The processor determines that the current sensor is normal when the shunt temperature difference is less than or equal to the reference value, the first switch temperature difference is less than or equal to the reference value, and the second switch temperature difference is less than or equal to the reference value.

11. The battery pack according to claim 9, wherein: The processor determines that the current sensor is abnormal when the shunt temperature difference exceeds the reference value, the first switch temperature difference is less than or equal to the reference value, and the second switch temperature difference is less than or equal to the reference value.

12. The battery pack according to claim 11, wherein: When determining that the current sensor is abnormal, the processor determines an abnormality type of the current sensor based on a sign of a difference between a shunt temperature and a shunt saturation temperature.

13. The battery pack according to claim 12, wherein: The processor determines that a shunt resistance value decrease fault has occurred when the difference between the shunt temperature and the shunt saturation temperature is negative, and determines that a shunt resistance value increase fault has occurred when the difference between the shunt temperature and the shunt saturation temperature is positive.

14. A current sensor diagnostic method, comprising: The processor calculates an average value of the current accumulated so far, and then obtains a shunt saturation temperature, a first switch saturation temperature, and a second switch saturation temperature corresponding to the calculated average current; The processor calculates a shunt temperature difference, a first switch temperature difference, and a second switch temperature difference, wherein the shunt temperature difference refers to an absolute value of a difference between a shunt temperature measured by a first temperature sensor and a shunt saturation temperature, the first switch temperature difference refers to an absolute value of a difference between a first switch temperature measured by a second temperature sensor and a first switch saturation temperature, and the second switch temperature difference refers to an absolute value of a difference between a second switch temperature measured by a third temperature sensor and a second switch saturation temperature; as well as An abnormality of the current sensor is diagnosed by the processor by comparing the shunt temperature difference, the first switch temperature difference, and the second switch temperature difference with a reference value.

15. The current sensor diagnosis method according to claim 14, wherein: When diagnosing an abnormality of the current sensor, the processor determines that the current sensor is normal when the shunt temperature difference is less than or equal to the reference value, the first switch temperature difference is less than or equal to the reference value, and the second switch temperature difference is less than or equal to the reference value.

16. The current sensor diagnosis method according to claim 14, wherein: In diagnosing an abnormality of the current sensor, the processor determines that the current sensor is abnormal when the shunt temperature difference exceeds the reference value, the first switch temperature difference is less than or equal to the reference value, and the second switch temperature difference is less than or equal to the reference value.

17. The current sensor diagnosis method according to claim 16, wherein: When determining that the current sensor is abnormal, the processor determines that a shunt resistance value decrease fault has occurred when the difference between the shunt temperature and the shunt saturation temperature is negative, and determines that a shunt resistance value increase fault has occurred when the difference between the shunt temperature and the shunt saturation temperature is positive.

18. A current sensor diagnostic method, comprising: receiving, by a processor, at least one of a shunt temperature measured by a first temperature sensor, a first switch temperature measured by a second temperature sensor, and a second switch temperature measured by a third temperature sensor; as well as The processor diagnoses abnormality of the current sensor by comparing at least one of the shunt temperature, the first switch temperature, and the second switch temperature with at least one of the preset shunt maximum temperature, the first switch maximum temperature, and the second switch maximum temperature.

19. The current sensor diagnosis method according to claim 18, wherein: When diagnosing an abnormality of the current sensor, the processor determines that the current sensor is normal when the shunt temperature difference is less than or equal to the reference value, the first switch temperature difference is less than or equal to the reference value, and the second switch temperature difference is less than or equal to the reference value.

20. The current sensor diagnosis method according to claim 18, wherein: In diagnosing an abnormality of the current sensor, the processor determines that the current sensor is abnormal when the shunt temperature difference exceeds the reference value, the first switch temperature difference is less than or equal to the reference value, and the second switch temperature difference is less than or equal to the reference value.

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