Battery pack, battery device, and electrolyte leak detection method

Abstract

A battery pack, a battery device, and an electrolyte leak detection method are provided. The battery pack includes a battery module containing a plurality of battery cells; a battery monitoring circuit connected to the battery module for monitoring the battery module; and an electrolyte leak detection sensor for detecting electrolyte leaking from the battery module. The electrolyte leak detection sensor may include a first resistor and an electrolyte detection unit connected in series between a power supply providing a first voltage and a ground terminal; a second resistor and a third resistor connected in series between the power supply and the ground terminal; and a comparison circuit that receives the sensing voltage at the contact between the first resistor and the electrolyte detection unit as a first input voltage, receives the voltage at the contact between the second resistor and the third resistor as a second input voltage, and transmits the output voltage to the input terminal of the battery monitoring circuit.

Description

Technical Field

[0001] Cross - reference to related applications This application claims the benefit of priority based on Korean Patent Application No. 10 - 2022 - 0183570 filed on December 23, 2022, and all the contents disclosed in the documents of the Korean Patent Application are included as part of this specification.

[0002] The disclosure relates to a battery pack, a battery device, and an electrolyte leakage detection method.

Background Art

[0003] An electric vehicle or a hybrid vehicle is a vehicle that mainly obtains power by driving a motor using a battery as a power source, and research is actively conducted because it can solve the pollution and energy problems of internal combustion engine vehicles. In addition, rechargeable batteries are used in various external devices other than vehicles.

[0004] A battery is provided in the form of a battery pack including battery modules in which a plurality of battery cells are connected. The lower case of the battery pack has a structure that is connected to an external device, for example, the chassis of a vehicle. In this case, if the electrolyte leaks from the battery cells of the battery pack, a path may be formed where the leaked electrolyte connects the battery cells and the lower case of the battery pack, and insulation may be destroyed. Due to insulation breakdown, a fire may occur in the battery pack or components using a low voltage in the vehicle may be damaged. Therefore, it is necessary to detect electrolyte leakage inside the battery pack.

Summary of the Invention

Problems to be Solved by the Invention

[0005] One problem to be solved is to provide a battery pack, a battery device, and an electrolyte leakage detection method capable of detecting electrolyte leakage inside the battery pack. [Means for solving the problem]

[0006] A battery pack according to one embodiment includes a battery module containing a plurality of battery cells; a battery monitoring circuit connected to the battery module for monitoring the battery module; and an electrolyte leak detection sensor for detecting electrolyte leaking from the battery module, wherein the electrolyte leak detection sensor may include a first resistor and an electrolyte detection unit connected in series between a power supply that provides a first voltage and a ground terminal; a second resistor and a third resistor connected in series between the power supply and the ground terminal; and a comparison circuit that receives the sensing voltage at the contact between the first resistor and the electrolyte detection unit as a first input voltage, receives the voltage at the contact between the second resistor and the third resistor as a second input voltage, and transmits the output voltage to the input terminal of the battery monitoring circuit.

[0007] In some embodiments, the output voltage may be a high-level voltage when the first input voltage is less than the second input voltage, and a low-level voltage when the first input voltage is greater than the second input voltage.

[0008] In some embodiments, if the output voltage is higher than the reference voltage, it can be diagnosed as an electrolyte leak in the battery module.

[0009] In some embodiments, the electrolyte detection unit includes a first detection node and a second detection node, and when the first detection node and the second detection node are electrically connected, an electrolyte leak in the battery module can be diagnosed.

[0010] In some embodiments, the battery pack may further include an RC filter circuit that receives the input of the sensing voltage at the contact between the first resistor and the electrolyte detection unit and transmits it to the comparison circuit.

[0011] In some embodiments, the battery pack may further include a voltage regulator that generates the first voltage from the voltage of the battery module.

[0012] In some embodiments, the battery pack may further include a lower case for the battery pack; and a lower cover formed on the lower case and below the battery module, which collects electrolyte leaking from the battery module and to which the detection sensor is attached.

[0013] In some embodiments, the battery monitoring circuit can monitor the battery module in active mode.

[0014] In some embodiments, the battery pack may further include a pulse generator that generates and outputs a pulse signal to an output terminal for switching the battery monitoring circuit to the active mode when the output voltage is higher than a threshold voltage; and a transmission circuit that transmits the pulse signal to the transmit terminal of the battery monitoring circuit in the shutdown mode of the battery monitoring circuit and blocks the transmission of the pulse signal to the transmit terminal of the battery monitoring circuit in the active mode.

[0015] A battery device according to one embodiment includes a battery module containing a plurality of battery cells; a battery monitoring circuit connected to the battery module for monitoring the battery module; an electrolyte leak detection sensor for detecting electrolyte leaks in the battery module; and a battery management system for managing the battery monitoring circuit, receiving information from the battery monitoring circuit, and diagnosing electrolyte leaks. The electrolyte leak detection sensor includes an electrolyte detection unit whose resistance value changes according to the electrolyte leaking in the battery module, and can transmit the output voltage of a comparison circuit determined based on the resistance value of the electrolyte detection unit to the input terminal of the battery monitoring circuit.

[0016] In some embodiments, the battery management system can diagnose electrolyte leakage in the battery module if it determines, based on information transmitted from the battery monitoring circuit, that the output voltage is higher than a reference voltage.

[0017] In some embodiments, the electrolyte leak detection sensor may include a first resistor and an electrolyte detection unit connected in series between a power supply providing a first voltage and a ground terminal; a second resistor and a third resistor connected in series between the power supply and the ground terminal; and a comparison circuit that receives the sensing voltage at the contact between the first resistor and the electrolyte detection unit as a first input voltage, receives the voltage at the contact between the second resistor and the third resistor as a second input voltage, and transmits the output voltage to the input terminal of the battery monitoring circuit.

[0018] In some embodiments, the battery device further includes a pulse generator that transmits a pulse signal to a transmitting terminal of the battery monitoring circuit when the electrolyte leak detection sensor detects electrolyte leaking from the battery module in the shutdown mode of the battery monitoring circuit, and the battery monitoring circuit can switch to an active mode in response to the pulse signal.

[0019] In some embodiments, the pulse generator can generate the pulse signal when the output voltage is higher than the threshold voltage.

[0020] In some embodiments, the battery device may further include a transistor connected between the output terminal of the pulse generator and the ground terminal, which controls the transmission of the pulse signal to the transmit terminal of the battery monitoring circuit in response to the voltage supplied to the power terminal of the battery monitoring circuit.

[0021] In some embodiments, a second voltage is supplied to the power terminals of the battery monitoring circuit in the active mode, and the supply of the second voltage to the power terminals of the battery monitoring circuit is cut off in the shutdown mode, and the transistor may be turned on in response to the second voltage in the active mode to cut off the transmission of the pulse signal, and turned off in response to the cutoff of the second voltage in the shutdown mode to transmit the pulse signal.

[0022] In some embodiments, the battery device may further include a lower cover formed at the bottom of the battery module, which collects any electrolyte leaking from the battery module and to which the detection sensor is attached.

[0023] An electrolyte leak detection method according to one embodiment is a method for detecting electrolyte leaks in a battery device including a battery module, a battery monitoring circuit for monitoring the battery module, and an electrolyte leak detection sensor, and includes the steps of: generating a pulse signal when electrolyte leaks from the battery module while the battery monitoring circuit is in shutdown mode; switching the battery monitoring circuit to active mode in response to the pulse signal; measuring an output voltage based on a resistance value that changes according to the leaking electrolyte of the electrolyte leak detection sensor; and diagnosing an electrolyte leak in the active mode battery monitoring circuit when the output voltage is higher than a reference voltage.

[0024] In some embodiments, the step of measuring the output voltage may include: receiving the sensing voltage at the contact between the first resistor and the electrolyte detection unit as the first input voltage; receiving the voltage at the contact between the second resistor and the third resistor as the second input voltage; and comparing the first input voltage and the second input voltage, outputting a high-level voltage if the first input voltage is smaller than the second input voltage, and outputting a low-level voltage if the first input voltage is larger than the second input voltage.

Advantages of the Invention

[0025] According to the embodiment, in electrolyte leakage detection, it is highly resistant to noise and can prevent malfunction. In addition, it can prevent the occurrence of a short circuit in the electrolyte leakage detection sensor, limit the current, and protect the battery module, the electrolyte leakage detection sensor, and the battery monitoring circuit.

Brief Description of the Drawings

[0026] [Figure 1] The drawing shows a battery device according to an embodiment. [Figure 2] The drawing shows an electrolyte leakage detection device according to an embodiment. [Figure 3] The drawing shows an electrolyte leakage detection device according to an embodiment. [Figure 4] The drawing shows the operation of an electrolyte leakage detection device according to an embodiment. [Figure 5] The drawing shows the operation of an electrolyte leakage detection device according to an embodiment. [Figure 6] The drawing shows an electrolyte leakage detection device according to an embodiment. [Figure 7] The flowchart shows the electrolyte leakage detection method of a battery device according to an embodiment. [Figure 8] The drawing shows an example of the structure of a battery pack according to an embodiment.

Modes for Carrying Out the Invention

[0027] Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those having ordinary knowledge in the technical field to which the present invention belongs can easily implement them. However, the present invention can be embodied in various different forms and is not limited to the embodiments described herein. In the drawings, in order to clearly explain the present invention, unnecessary parts in the description are omitted, and similar parts throughout the specification are denoted by similar reference numerals.

[0028] When it is mentioned that one component is "connected" to another, it must be understood that it may be directly connected to the other component, or there may be other components in between. Conversely, when it is mentioned that one component is "directly connected" to another, it must be understood that there are no other components in between.

[0029] In the following explanations, expressions written in the singular can be interpreted as either singular or plural unless explicitly stated as "one" or "single."

[0030] In the flowchart explained with reference to the diagram, the order of operations may be changed, multiple operations may be merged, certain operations may be split, and certain operations may not be performed.

[0031] Figure 1 is a diagram showing a battery device according to one embodiment.

[0032] Referring to Figure 1, the battery device may include a battery pack 100 and a battery management system 10. The battery pack 100 may include a battery module 110 and an electrolyte leak detection circuit 120.

[0033] The battery module 110 may include a plurality of battery cells (not shown). In one embodiment, the battery cells may be rechargeable batteries, and such battery cells may include a positive electrode, a negative electrode, and an electrolyte. In one embodiment, a predetermined number of battery cells may be connected in series or parallel to form a battery module. Although Figure 1 shows one battery module 110 for illustrative purposes, the battery pack 100 may include one or more battery modules 110 to supply the desired power.

[0034] The electrolyte leak detection circuit 120 may include an electrolyte leak detection sensor 121 and a battery monitoring circuit 122.

[0035] The electrolyte leak detection sensor 121 is connected to the battery module 110 and can detect electrolyte leaks from the battery cells contained in the battery module 110. When an electrolyte leak is detected, it can transmit a signal to the battery monitoring circuit 122.

[0036] The battery monitoring circuit 122 is connected to the battery module 110 and can monitor the voltage of the battery cells. In one embodiment, the battery monitoring circuit 122 can also measure the temperature of the battery module 110. In one embodiment, the battery monitoring circuit 122 may be provided in the form of an integrated circuit (IC). When the battery monitoring circuit 122 receives a signal from the electrolyte leak detection sensor 121, it can transmit this information to an external device (e.g., a vehicle).

[0037] The battery monitoring circuit 122 can communicate with the battery management system 10 of the battery device. The battery management system 10 can collect data (information) transmitted from the battery monitoring circuit 122 and control the operation of the battery pack 100. The battery management system 10 can also transmit the information collected from the battery monitoring circuit 122 to an external device (for example, a vehicle).

[0038] Figures 2 and 3 are diagrams showing an electrolyte leak detection device according to one embodiment.

[0039] Referring to Figure 2, the electrolyte leak detection device 200 may include an electrolyte leak detection sensor 210 and a battery monitoring circuit 220. In one embodiment, the electrolyte leak detection device 200 may correspond to the electrolyte leak detection circuit 120 in Figure 1.

[0040] In one embodiment, the power supply providing a predetermined voltage Vs can be generated from the voltage of a battery module (e.g., 110 in Figure 1). For this purpose, the electrolyte leak detection device 200 may further include a voltage regulator 230. The voltage regulator 230 can receive the voltage Vm of the battery module 110 through its input terminal IN and output a predetermined voltage Vs through its output terminal OUT. The voltage Vs may be, for example, 5V.

[0041] The electrolyte leak detection sensor 210 may include a resistor 211 and an electrolyte detection unit 212 connected in series between a power supply providing a predetermined voltage Vs and the ground terminal. The voltage at the contact point between the resistor 211 and the electrolyte detection unit 212 can be transmitted as a sensing voltage to RC filter circuits 213 and 214. The sensing voltage after passing through the RC filter circuits 213 and 214 can be input to the comparator circuit 215 as a first input voltage Via. Here, the comparator circuit 215 is an operational amplifier (OP amp), and the first input voltage Via may be the voltage applied to the negative input terminal of the OP amp. On the other hand, the electrolyte leak detection sensor 210 may further include a plurality of resistors 216 and 217 connected in series between a power supply providing a predetermined voltage Vs and the ground terminal. The voltage at the contact points of the plurality of resistors 216 and 217 can be input to the comparator circuit 215 as a second input voltage Vib. Here, the second input voltage Vib may be the voltage applied to the positive input terminal of the OP amp.

[0042] The second input voltage Vib may be a fixed voltage to allow the op-amp to operate as a voltage comparator. For example, multiple resistors 216, 217 may be set to the same resistance value so that the second input voltage Vib is half the value of voltage Vs. This allows the op-amp's output voltage Vo to be at a low level when the first input voltage Via applied to the op-amp's negative input terminal is greater than the second input voltage Vib. Conversely, when the first input voltage Via applied to the op-amp's negative input terminal is less than the second input voltage Vib, the op-amp's output voltage Vo can be at a high level.

[0043] In one embodiment, when the voltage Vs is set to 5V, resistors 211, 213, 216, and 217 can be 170kΩ, 10kΩ, 43kΩ, and 43kΩ, respectively, and a 47uF capacitor 214 can be used.

[0044] The electrolyte detection unit 212 does not form a current path if the electrolyte from the battery cell does not leak, but can form a current path with the leaked electrolyte if the electrolyte from the battery cell leaks. Referring to Figure 3, the electrolyte detection unit 212 may include two electrolyte detection nodes N1 and N2 that are spaced apart from each other. When the electrolyte from the battery cell leaks, the first detection node N1 and the second detection node N2 can be electrically connected.

[0045] As shown in Figure 3, when the electrolyte is located at the first detection node N1 and the second detection node N2, the electrolyte acts as a resistor with a value similar to that of resistor 211. However, if resistor 211 is set to 170kΩ, it can produce the effect of a 170kΩ resistor being connected in series between the voltage Vs and the ground terminal. As a result, the sensing voltage at the contact point between resistor 211 and the electrolyte detection unit 212 becomes a voltage value corresponding to half of the voltage Vs (2.5V when the voltage Vs is 5V) and can be applied to the comparator circuit 215 as the first input voltage Via. At this time, the second input voltage Vib of the comparator circuit 215 may be a voltage value corresponding to half of the voltage Vs (2.5V when the voltage Vs is 5V). However, although the resistance value of the electrolyte is initially 170kΩ, it gradually decreases over time. As a result, the first input voltage Via becomes lower than the voltage value corresponding to half of the voltage Vs. Therefore, in the case where the first input voltage Via applied to the - input terminal is smaller than the second input voltage Vib applied to the + input terminal, the output voltage Vo of the comparator circuit 215 can become high level (e.g., 5V).

[0046] In contrast, if there is no electrolyte leakage from the battery cell, the first detection node N1 and the second detection node N2 are not electrically connected, and the sensing voltage at the contact between the resistor 211 and the electrolyte detection unit 212 becomes a voltage value corresponding to the voltage Vs (5V if the voltage Vs is 5V) and can be applied to the comparator circuit 215 as the first input voltage Via. At this time, the second input voltage Vib of the comparator circuit 215 is a voltage value corresponding to half of the voltage Vs (2.5V if the voltage Vs is 5V), so the case where the first input voltage Via applied to the - input terminal is greater than the second input voltage Vib applied to the + input terminal occurs, and the output voltage Vo of the comparator circuit 215 can be low level (for example, 0V).

[0047] The battery monitoring circuit 220 can receive a signal corresponding to the output voltage Vo of the electrolyte leak detection sensor 210 through an input terminal IN (e.g., an input pin). In one embodiment, input terminal IN may be one of a variety of input terminals provided for receiving monitoring results in the battery monitoring circuit 220. In one embodiment, the electrolyte leak detection device 200 may further include an analog-to-digital converter (ADC) 240 for converting the output voltage Vo of the electrolyte leak detection sensor 210 into a digital signal that can be received by the battery monitoring circuit 220. In one embodiment, the electrolyte leak detection device 200 may further include a diode D1 to block the current path in the opposite direction (i.e., the current path from the input terminal IN of the battery monitoring circuit 220 to the output terminal of the electrolyte leak detection sensor 210). The diode D1 may have its anode connected to the output terminal of the electrolyte leak detection sensor 210 and its cathode connected to the input terminal IN of the battery monitoring circuit 220.

[0048] The battery monitoring circuit 220 can operate using a predetermined voltage V_BMIC supplied to the power supply terminal Vcc (e.g., power supply pin). In one embodiment, the predetermined voltage V_BMIC may be the same voltage as the power supply voltage Vs of the electrolyte leak detection sensor 210. The battery monitoring circuit 220 can also communicate with a battery management system (e.g., 10 in Figure 1) through a transmit terminal Tx (e.g., transmit pin) and a receive terminal Rx (e.g., receive pin). The battery monitoring circuit 220 can transmit monitored data to the battery management system 10 through a transmit communication line connected between the transmit terminal Tx and the battery management system 10, and can receive control signals from the battery management system 10 through a receive communication line connected between the receive terminal Rx and the battery management system 10. In one embodiment, communication between the battery monitoring circuit 220 and the battery management system 10 may be UART (universal asynchronous receiver / transmitter) communication.

[0049] The battery monitoring circuit 220 can transmit information corresponding to the output voltage Vo of the electrolyte leak detection sensor 210 received through the input terminal IN to, for example, the battery management system 10. As mentioned above, if there is no electrolyte leak, the output voltage Vo of the electrolyte leak detection sensor 210 is a low level voltage (e.g., 0V), so the battery management system 10 or the processor of an external device (e.g., a vehicle) can determine that there is no electrolyte leak if the output voltage Vo of the electrolyte leak detection sensor 210 is lower than the reference voltage.

[0050] On the other hand, if electrolyte leaks, the output voltage Vo of the electrolyte leak detection sensor 210 is a high voltage (e.g., 5V). Therefore, the battery management system 10 or the processor of an external device can determine that electrolyte has leaked if the output voltage Vo of the electrolyte leak detection sensor 210 is higher than the reference voltage. In this way, the battery management system 10 or the external device can detect electrolyte leakage in the battery pack through the output signal of the battery monitoring circuit 220 and perform protective actions. In one embodiment, the battery management system 10 can transmit a warning signal to an external device (e.g., a vehicle) if the output voltage Vo is higher than the reference voltage. This allows the vehicle operator to have the battery pack inspected.

[0051] According to this embodiment, a resistor 211 is placed between the power supply and the ground terminal, directly connecting the electrolyte detection unit 212 and the power supply, which prevents a short circuit from occurring between the voltage Vs and the ground terminal, thereby limiting the current and protecting the battery module 110, the electrolyte leak detection sensor 210, and the battery monitoring circuit 220. Furthermore, the electrolyte detection unit 212 is designed to be considered an open circuit when there is no electrolyte leak, thereby preventing the generation of leakage current. In addition, by adopting RC filter circuits 213 and 214, the detection accuracy can be improved by preventing false detection of the presence or absence of electrolyte leaks due to momentary AC noise.

[0052] Figures 4 and 5 are diagrams illustrating the operation of an electrolyte leak detection device according to one embodiment.

[0053] Referring to Figures 4 and 5, time interval T1 can correspond to a normal state where no leakage has occurred. In time interval T1, the first input voltage Via applied to the - input terminal of the comparator circuit 215 may be 5V (see A). At this time, the output voltage Vo output from the output terminal of the comparator circuit 215 may be 0V (see E). Here, the second input voltage Vib applied to the + input terminal of the comparator circuit 215 may be 2.5V (see D).

[0054] The time interval T2 can correspond to a state in which leakage occurs. Due to the leakage, the first input voltage Via applied to the - input terminal of the comparator circuit 215 can be reduced to 2.5V (see B). Subsequently, as described above, the first input voltage Via can be further reduced to a voltage lower than 2.5V due to the decrease in the resistance of the electrolyte. As a result, the output voltage Vo output from the output terminal of the comparator circuit 215 can be 5V (see F).

[0055] Time interval T3 can correspond to the normal state after the leaked fluid has been removed. In time interval T3, the first input voltage Via applied to the negative input terminal of the comparator circuit 215 may be 5V (see C). At this time, the output voltage Vo output from the output terminal of the comparator circuit 215 may be 0V (see G).

[0056] Figure 6 is a diagram showing an electrolyte leak detection device according to one embodiment.

[0057] Referring to Figure 6, the electrolyte leak detection device 300 may include an electrolyte leak detection sensor 310 and a battery monitoring circuit 320. In one embodiment, the electrolyte leak detection device 300 may correspond to the electrolyte leak detection circuit 120 in Figure 1.

[0058] The electrolyte leak detection sensor 310 includes a resistor 311 and an electrolyte detection unit 312 connected in series between a power supply that provides a predetermined voltage Vs and the ground terminal. The voltage at the contact point between the resistor 311 and the electrolyte detection unit 312 can be transmitted as a sensing voltage to RC filter circuits 313 and 314. The sensing voltage after passing through the RC filter circuits 313 and 314 can be input to the comparator circuit 315 as a first input voltage Via. On the other hand, the electrolyte leak detection sensor 310 may further include a plurality of resistors 316 and 317 connected in series between a power supply that provides a predetermined voltage Vs and the ground terminal. The voltages at the contact points of the plurality of resistors 316 and 317 can be input to the comparator circuit 315 as a second input voltage Vib. In one embodiment, the electrolyte leak detection device 300 may further include a voltage regulator 330 that generates a predetermined voltage Vs.

[0059] The battery monitoring circuit 320 can receive a signal corresponding to the output voltage Vo of the electrolyte leak detection sensor 310. In one embodiment, the electrolyte leak detection device 300 may further include an ADC 340 for converting the output voltage Vo of the electrolyte leak detection sensor 310 into a digital signal that can be received by the battery monitoring circuit 320. In one embodiment, the electrolyte leak detection device 300 may further include a diode D1 for blocking the current path in the opposite direction.

[0060] In one embodiment, the battery monitoring circuit 320 can be set to one of two modes: an active mode that monitors the battery module (e.g., 110 in Figure 1) and a shutdown mode that does not monitor the battery module 110. In the active mode, a predetermined voltage V_BMIC is supplied to the power terminal Vcc (e.g., power pin) of the battery monitoring circuit 320, allowing the battery monitoring circuit 320 to operate. In the shutdown mode, the predetermined voltage V_BMIC supplied to the power terminal Vcc of the battery monitoring circuit 320 is cut off, allowing the battery monitoring circuit 320 to remain inoperable. In one embodiment, the predetermined voltage V_BMIC may be the same as a predetermined voltage Vs supplied to the electrolyte leak detection sensor 310. In one embodiment, the electrolyte leak detection device 300 may further include a pulse generator 350 so that electrolyte leaks can be detected even when the battery monitoring circuit 320 is in shutdown mode.

[0061] The output voltage Vo of the electrolyte leak detection sensor 310 may be supplied to the input terminal IN of the pulse generator 350. In one embodiment, the signal obtained by converting the output voltage Vo of the electrolyte leak detection sensor 310 by the ADC 340 may be input to the input terminal IN of the pulse generator 350. In one embodiment, the electrolyte leak detection device 300 may further include a diode D2 for blocking the current path in the opposite direction (i.e., the current path from the input terminal IN of the pulse generator 350 to the electrolyte leak detection sensor 310). The diode D2 may have its anode connected to the output terminal of the electrolyte leak detection sensor 310 and its cathode connected to the input terminal IN of the pulse generator 350.

[0062] A transistor 351 may be connected between the output terminal OUT of the pulse generator 350 and the ground terminal. That is, the first terminal of the transistor 351 is connected to the output terminal OUT of the pulse generator 350, and the second terminal of the transistor 351 is connected to the ground terminal. The control terminal of the transistor 351 receives the same voltage as the power supply terminal Vcc of the battery monitoring circuit 320. For example, the control terminal of the transistor 351 may be connected to the power supply terminal Vcc of the battery monitoring circuit 320. The first terminal of the transistor 351 may also be connected to the transmit terminal Tx (e.g., transmit pin) of the battery monitoring circuit 320. In one embodiment, the first terminal of the transistor 351 may be connected to a transmit communication line between the transmit terminal Tx of the battery monitoring circuit 320 and the battery management system (e.g., 10 in Figure 1). In one embodiment, the electrolyte leak detection device 300 may further include a diode D3 to block the current path in the opposite direction (i.e., the current path from the transmit communication line to the first terminal of the transistor 351). Diode D3 may have its anode connected to the first terminal of transistor 351 and its cathode connected to the transmit terminal Tx of battery monitoring circuit 320. In one embodiment, a resistor 352 may be connected between the output terminal OUT of pulse generator 350 and the first terminal of transistor 351.

[0063] Transistor 351 can be turned on when a predetermined voltage (e.g., 5V) is applied to the power supply terminal Vcc of the battery monitoring circuit 320, and turned off when the voltage applied to the power supply terminal Vcc of the battery monitoring circuit 320 is interrupted. In one embodiment, transistor 351 may be an n-channel transistor, such as an n-channel MOSFET (metal oxide semiconductor field effect transistor). In this case, the first terminal, second terminal, and control terminal of transistor 351 may be the drain, source, and gate, respectively.

[0064] In active mode, the electrolyte leak detection sensor 310 and the battery monitoring circuit 320 operate identically to the electrolyte leak detection sensor 210 and the battery monitoring circuit 220 described with reference to Figure 2, so their description is omitted. On the other hand, in active mode, a predetermined voltage is applied to the power terminal Vcc of the battery monitoring circuit 320, causing the transistor 351 to turn on. As a result, 0V is applied to the anode of diode D3, so it does not affect communication through the transmission terminal Tx of the battery monitoring circuit 320.

[0065] In shutdown mode, the voltage applied to the power terminal Vcc of the battery monitoring circuit 320 is cut off, so the transistor 351 is turned off. Also, if electrolyte leaks, the electrolyte leak detection sensor 310 outputs an output voltage Vo, so the pulse generator 350 can generate a pulse signal in response to the output voltage Vo of the electrolyte leak detection sensor 310 and output it to the output terminal OUT. In other words, the pulse generator 350 can generate a pulse signal and output it to the output terminal OUT if the voltage input to the input terminal IN is higher than the threshold voltage. In this case, since the transistor 351 is turned off, the pulse signal from the pulse generator 350 can be applied to the transmission terminal Tx of the battery monitoring circuit 320. The battery monitoring circuit 320 can switch to active mode in response to the pulse signal transmitted to the transmission terminal Tx. Then, the battery monitoring circuit 320 can transmit information corresponding to the output voltage Vo of the electrolyte leak detection sensor 310 to the battery management system 10.

[0066] In one embodiment, the transistor 351, resistor 352, and diode D3 can operate as a transmission circuit that transmits the pulse signal from the pulse generator 350 to the transmit terminal Tx of the battery monitoring circuit 320 in shutdown mode, and blocks the transmission of the pulse signal in active mode.

[0067] According to the embodiments described above, electrolyte leakage can be detected even when the battery monitoring circuit 320 is in shutdown mode.

[0068] Figure 7 is a flowchart showing a method for detecting electrolyte leakage in a battery device according to one embodiment.

[0069] Referring to Figure 7, when the battery monitoring circuit of the battery pack is in active mode (S710), the battery monitoring circuit measures the voltage corresponding to electrolyte leakage (S750). In one embodiment, the battery monitoring circuit can measure the sensing voltage output from the electrolyte leakage detection sensor (S750).

[0070] When the battery monitoring circuit of the battery pack is in shutdown mode, if electrolyte leakage occurs inside the battery pack (S720), the battery device generates a pulse signal in response to the electrolyte leakage (S730). The battery monitoring circuit switches to active mode in response to the pulse signal (S740) and measures the voltage corresponding to the electrolyte leakage (S750). In one embodiment, a pulse generator may generate a pulse signal in response to the output voltage of a comparison circuit corresponding to the electrolyte leakage output from an electrolyte leakage detection sensor, and the battery monitoring circuit may switch to active mode in response to the pulse signal from the pulse generator.

[0071] If the voltage measured by the battery monitoring circuit is higher than the reference voltage (S760), the battery device can diagnose electrolyte leakage and transmit a warning signal to an external device (e.g., a vehicle) (S770). If the measured voltage is not higher than the reference voltage, the battery device can diagnose that there is no electrolyte leakage (S780).

[0072] Next, a battery pack to which an electrolyte leak detection method according to various embodiments can be applied will be described with reference to Figure 8.

[0073] Figure 8 is a diagram showing an example of the structure of a battery pack according to one embodiment.

[0074] Referring to Figure 8, the battery pack 500 is formed by joining a lower case 510 and an upper case (not shown), and contains a battery module 520 inside. In Figure 5, for the sake of explanation, the battery pack 500 is shown to contain four battery modules 520, but the number of battery modules 520 is not limited to this. A battery monitoring circuit 530 is connected to each battery module 520. The battery monitoring circuit 530 can monitor the battery cell voltage, temperature, etc. of the corresponding battery module 520.

[0075] A lower cover 540 may be formed at the bottom of each battery module 520. The lower cover 540 may have a shape that can collect electrolyte leaking from the corresponding battery module 520. An electrolyte leak detection sensor 550 may be attached to the lower cover 540. The electrolyte leak detection sensor 550 can sense the electrolyte that collects in the lower cover 540 and output a corresponding voltage.

[0076] In one embodiment, an internal battery pack cover 560 can be formed on the lower case 510. The internal battery pack cover 560 may be formed between the lower case 510 and the lower cover 540. The internal battery pack cover 560 is made of an insulator so that any leaked electrolyte can block the current path that may be formed between it and the lower case 510.

[0077] Although embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto. Various modifications and improvements made by those skilled in the art, utilizing the basic concepts of the present invention as defined in the claims, also fall within the scope of the present invention.

Claims

1. A battery module containing multiple battery cells; A battery monitoring circuit connected to the aforementioned battery module for monitoring the aforementioned battery module; and The battery module is equipped with an electrolyte leak detection sensor that detects the leakage of electrolyte, The aforementioned electrolyte leak detection sensor is A first resistor and an electrolyte detection unit are connected in series between the power supply providing the first voltage and the ground terminal; A second resistor and a third resistor connected in series between the power supply and the ground terminal; and The system includes a comparison circuit that receives the sensing voltage at the contact between the first resistor and the electrolyte detection unit as the first input voltage, receives the voltage at the contact between the second resistor and the third resistor as the second input voltage, and transmits the output voltage to the input terminal of the battery monitoring circuit. Battery pack.

2. The battery pack according to claim 1, wherein the output voltage is a high-level voltage when the first input voltage is less than the second input voltage, and a low-level voltage when the first input voltage is greater than the second input voltage.

3. The battery pack according to claim 2, wherein if the output voltage is higher than the reference voltage, an electrolyte leak in the battery module is diagnosed.

4. The battery pack according to claim 1, wherein the electrolyte detection unit includes a first detection node and a second detection node, and when the first detection node and the second detection node are electrically connected, an electrolyte leak in the battery module is diagnosed.

5. The battery pack according to any one of claims 1 to 4, further comprising an RC filter circuit that receives the input of the sensing voltage at the contact between the first resistor and the electrolyte detection unit and transmits it to the comparison circuit.

6. The battery pack according to any one of claims 1 to 4, further comprising a voltage regulator that generates the first voltage from the voltage of the battery module.

7. The lower case of the battery pack; and The battery pack according to any one of claims 1 to 4, further comprising a lower cover formed on the lower case and below the battery module, which collects electrolyte leaking from the battery module and to which the detection sensor is attached.

8. The battery pack according to any one of claims 1 to 4, wherein the battery monitoring circuit monitors the battery module in active mode.

9. A pulse generator that generates a pulse signal to switch the battery monitoring circuit to the active mode and outputs it to the output terminal when the output voltage is higher than the threshold voltage; and The battery pack according to claim 8, further comprising a transmission circuit that transmits the pulse signal to the transmission terminal of the battery monitoring circuit in the shutdown mode of the battery monitoring circuit, and blocks the transmission of the pulse signal to the transmission terminal of the battery monitoring circuit in the active mode.

10. A battery module containing multiple battery cells; A battery monitoring circuit connected to the aforementioned battery module for monitoring the aforementioned battery module; An electrolyte leak detection sensor for detecting electrolyte leaks from the battery module; and The battery management system includes a battery monitoring circuit that manages the aforementioned battery monitoring circuit and receives information from the battery monitoring circuit to diagnose electrolyte leakage. The electrolyte leak detection sensor includes an electrolyte detection unit whose resistance value changes according to the electrolyte leaking from the battery module, and transmits the output voltage of a comparison circuit, determined based on the resistance value of the electrolyte detection unit, to the input terminal of the battery monitoring circuit. Battery device.

11. The battery device according to claim 10, wherein the battery management system diagnoses that electrolyte is leaking from the battery module when it determines, based on information transmitted from the battery monitoring circuit, that the output voltage is higher than a reference voltage.

12. The aforementioned electrolyte leak detection sensor is A first resistor and the electrolyte detection unit are connected in series between the power supply that provides the first voltage and the ground terminal; A second resistor and a third resistor connected in series between the power supply and the ground terminal; and The device includes a comparison circuit that receives the sensing voltage at the contact between the first resistor and the electrolyte detection unit as the first input voltage, receives the voltage at the contact between the second resistor and the third resistor as the second input voltage, and transmits the output voltage to the input terminal of the battery monitoring circuit. The battery device according to claim 10 or 11.

13. When the electrolyte leak detection sensor detects electrolyte leakage in the battery module during the shutdown mode of the battery monitoring circuit, the battery monitoring circuit further includes a pulse generator that transmits a pulse signal to the transmission terminal of the battery monitoring circuit. The battery monitoring circuit switches to active mode in response to the pulse signal. The battery device according to claim 12.

14. The battery device according to claim 13, wherein the pulse generator generates the pulse signal when the output voltage is higher than the threshold voltage.

15. The battery device according to claim 13, further comprising a transistor connected between the output terminal and the ground terminal of the pulse generator, which controls the transmission of the pulse signal to the transmit terminal of the battery monitoring circuit in response to the voltage supplied to the power terminal of the battery monitoring circuit.

16. In the active mode, a second voltage is supplied to the power terminals of the battery monitoring circuit, and in the shutdown mode, the supply of the second voltage to the power terminals of the battery monitoring circuit is cut off. The transistor is turned on in the active mode in response to the second voltage to interrupt the transmission of the pulse signal, and is turned off in the shutdown mode in response to the interruption of the second voltage in order to transmit the pulse signal. The battery device according to claim 15.

17. The battery device according to claim 10 or 11, further comprising a lower cover formed at the bottom of the battery module, which collects electrolyte leaking from the battery module and to which the detection sensor is attached.

18. A method for detecting electrolyte leakage in a battery device, comprising a battery module, a battery monitoring circuit for monitoring the battery module, and an electrolyte leakage detection sensor, If electrolyte leaks from the battery module while the battery monitoring circuit is in shutdown mode, the step of generating a pulse signal; A step of switching the battery monitoring circuit to active mode in response to the pulse signal; The steps include: the electrolyte leak detection sensor measuring the output voltage based on a resistance value that changes according to the leaking electrolyte; and The battery monitoring circuit in the active mode includes a step of diagnosing electrolyte leakage when the output voltage is higher than the reference voltage. Method for detecting electrolyte leakage.

19. The steps of obtaining the output voltage or more are: The step of receiving the sensing voltage at the contact point between the first resistor and the electrolyte detection unit as the first input voltage; The step of receiving the voltage at the contact point between the second resistor and the third resistor as the second input voltage; and The electrolyte leak detection method according to claim 18, further comprising the step of comparing the first input voltage with the second input voltage, outputting a high-level voltage when the first input voltage is smaller than the second input voltage, and outputting a low-level voltage when the first input voltage is larger than the second input voltage.

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