Battery pack, battery apparatus, and electrolyte leak detection method

Abstract

A battery pack, a battery apparatus, and an electrolyte leak detection method are provided. The battery pack may include: a battery module including a plurality of battery cells; a battery monitoring circuit connected to the battery module and monitoring the battery module; and an electrolyte leak detection sensor that detects an electrolyte leaked from the battery module, in which the electrolyte leak detection sensor includes: 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 to which a sensing voltage at a contact between the first resistor and the electrolyte detection unit is input as a first input voltage, and to which a voltage at a contact between the second resistor and the third resistor is input as a second input voltage, and the comparison circuit transmits the output voltage to an input terminal of the battery monitoring circuit.

Description

Technical Field

[0001] Cross - Reference to Related Applications

[0002] This application claims the priority and benefit of Korean Patent Application No. 10 - 2022 - 0183570, filed with the Korean Intellectual Property Office on December 23, 2022, the entire contents of which are incorporated herein by reference.

[0003] The present disclosure relates to a battery pack, a battery device, and a method for detecting electrolyte solution leakage. Background Art

[0004] Electric vehicles and hybrid vehicles are vehicles that obtain power mainly by using a battery as a power source for driving a motor and are alternatives that can solve the pollution and energy problems of internal combustion vehicles. For this reason, active research has been conducted on them. In addition, rechargeable batteries have been used in various other external devices as well as in vehicles.

[0005] The battery is provided in the form of a battery pack including battery modules, and a plurality of battery cells are connected in each battery module. The lower case of the battery pack has a structure connected to an external device (e.g., the chassis of a vehicle). In this case, if the electrolyte solution leaks from the battery cells of the battery pack, the leaked electrolyte solution may create a path between the battery cells of the battery pack and the lower case, which may disrupt insulation. This insulation disruption may cause the battery pack to catch fire or damage components that use low voltage in the vehicle. For this reason, it is necessary to detect the leakage of the electrolyte solution in the battery pack. Summary of the Invention

[0006] Technical Problem

[0007] The present disclosure attempts to provide a battery pack, a battery device, and a method for detecting electrolyte solution leakage in the battery pack that can detect the leakage of the electrolyte solution.

[0008] Technical Solution

[0009] A battery pack according to an exemplary embodiment may include: a battery module including a plurality of battery cells; a battery monitoring circuit connected to the battery module and monitoring the battery module; and an electrolyte solution leakage detection sensor for detecting the electrolyte solution leaked in the battery module, wherein the electrolyte solution leakage detection sensor may include: a first resistor and an electrolyte solution detection unit, the first resistor and the electrolyte solution detection unit being connected in series between a power supply for providing a first voltage and a ground terminal; a second resistor and a third resistor, the second resistor and the third resistor being connected in series between the power supply and the ground terminal; and a comparison circuit receiving a detection voltage at a contact point of the first resistor and the electrolyte solution detection unit as a first input voltage, and receiving a voltage at a contact point of the second resistor and the third resistor as a second input voltage, and transmitting an output voltage to an input terminal of the battery monitoring circuit.

[0010] In some exemplary embodiments, when the first input voltage is less than the second input voltage, the output voltage may be a high-level voltage, and when the first input voltage is greater than the second input voltage, the output voltage may be a low-level voltage.

[0011] In some exemplary embodiments, when the output voltage is higher than a reference voltage, it may be diagnosed that the electrolyte solution in the battery module leaks.

[0012] In some exemplary embodiments, the electrolyte solution detection unit may include a first detection node and a second detection node, and when the first detection node and the second detection node are electrically connected, it may be diagnosed that the electrolyte solution in the battery module leaks.

[0013] In some exemplary embodiments, the battery pack may further include an RC filter circuit that receives the detection voltage at the contact point of the first resistor and the electrolyte solution detection unit and transmits the detection voltage to the comparison circuit.

[0014] In some exemplary embodiments, the battery pack may further include a voltage regulator that generates the first voltage according to the voltage of the battery module.

[0015] In some exemplary embodiments, the battery pack may further include a lower housing of the battery pack; and a lower cover formed on the lower housing, formed below the battery module, collecting the electrolyte solution leaked in the battery module, and the electrolyte solution leakage detection sensor is attached to the lower cover.

[0016] In some exemplary embodiments, the battery monitoring circuit may monitor the battery module in an active mode.

[0017] In some exemplary embodiments, the battery pack may further include a pulse generator that generates a pulse signal for switching the battery monitoring circuit to the active mode and outputs the pulse signal to an output terminal when the output voltage is higher than a threshold voltage; and a transmission circuit that transmits the pulse signal to a sending terminal of the battery monitoring circuit in a shutdown mode of the battery monitoring circuit and blocks transmission of the pulse signal to the sending terminal of the battery monitoring circuit in the active mode.

[0018] A battery device according to an exemplary embodiment may include: a battery module including a plurality of battery cells; a battery monitoring circuit connected to the battery module and monitoring the battery module; an electrolyte solution leakage detection sensor that detects electrolyte solution leaking in the battery module; and a battery management system that manages the battery monitoring circuit and diagnoses leakage of the electrolyte solution by receiving information from the battery monitoring circuit, and the electrolyte solution leakage detection sensor may include an electrolyte solution detection unit whose resistance value changes in response to the electrolyte solution leaking in the battery module and transmits an output voltage of a comparison circuit determined based on the resistance value of the electrolyte solution detection unit to an input terminal of the battery monitoring circuit.

[0019] In some exemplary embodiments, when it is determined based on information transmitted from the battery monitoring circuit that the output voltage is higher than a reference voltage, the battery management system may diagnose that electrolyte solution has leaked in the battery module.

[0020] In some exemplary embodiments, the electrolyte solution leakage detection sensor may include a first resistor and the electrolyte solution detection unit, the first resistor and the electrolyte solution detection unit being connected in series between a power supply for providing a first voltage and a ground terminal; a second resistor and a third resistor, the second resistor and the third resistor being connected in series between the power supply and the ground terminal; and a comparison circuit that receives a detection voltage at a contact point of the first resistor and the electrolyte solution detection unit as a first input voltage, and receives a voltage at a contact point of the second resistor and the third resistor as a second input voltage, and transmits an output voltage to an input terminal of the battery monitoring circuit.

[0021] In some exemplary embodiments, the battery device may further include a pulse generator. When the electrolyte solution leakage detection sensor detects leakage of the electrolyte solution in the battery module in the off mode of the battery monitoring circuit, the pulse generator transmits a pulse signal to a transmission terminal of the battery monitoring circuit, and the battery monitoring circuit may switch to an active mode in response to the pulse signal.

[0022] In some exemplary embodiments, the pulse generator may generate a pulse signal when the output voltage is higher than a threshold voltage.

[0023] In some exemplary embodiments, the battery device may further include a transistor connected between an output terminal of the pulse generator and a ground terminal, and controlling transmission of the pulse signal to the transmission terminal of the battery monitoring circuit in response to a voltage provided to a power supply terminal of the battery monitoring circuit.

[0024] In some exemplary embodiments, in the active mode, a second voltage may be provided to the power supply terminal of the battery monitoring circuit, and in the off mode, the second voltage may be blocked so as not to be provided to the power supply terminal of the battery monitoring circuit, and the transistor may be turned on in response to the second voltage in the active mode to block transmission of the pulse signal, and may be turned off in response to blocking of the second voltage in the off mode to transmit the pulse signal.

[0025] In some exemplary embodiments, the battery device may further include a lower cover formed under the battery module to collect the electrolyte solution leaked in the battery module, and the electrolyte solution leakage detection sensor is attached to the lower cover.

[0026] An electrolyte solution leakage detection method according to an exemplary embodiment is an electrolyte solution leakage detection method of a battery device, the battery device including a battery module, a battery monitoring circuit for monitoring the battery module, and an electrolyte solution leakage detection sensor, and may include the following steps: generating a pulse signal when the electrolyte solution leaks in the battery module while the battery monitoring circuit is in an off mode; switching the battery monitoring circuit to an active mode in response to the pulse signal; allowing the electrolyte solution leakage detection sensor to measure an output voltage based on a resistance value that changes in response to the electrolyte solution leakage; and when the output voltage is higher than a reference voltage, allowing the battery monitoring circuit in the active mode to diagnose leakage of the electrolyte solution.

[0027] In some exemplary embodiments, the step of measuring the output voltage may include the following steps: receiving a detection voltage at a contact point of a first resistor and an electrolyte solution detection unit as a first input voltage; receiving a voltage at a contact point of a second resistor and a third resistor as a second input voltage; and comparing the first input voltage and the second input voltage, outputting a high-level voltage when the first input voltage is less than the second input voltage, and outputting a low-level voltage when the first input voltage is greater than the second input voltage.

[0028] Advantageous Effects

[0029] According to an exemplary embodiment, since electrolyte solution leakage detection is noise-robust, short-circuit of the electrolyte solution leakage detection sensor can be prevented, while preventing malfunctions, and the battery module, the electrolyte solution leakage detection sensor, and the battery monitoring circuit can be protected by limiting the current. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a diagram showing a battery device according to an exemplary embodiment.

[0031] Figure 2 and Figure 3 is a diagram showing an electrolyte solution leakage detection device according to an exemplary embodiment.

[0032] Figure 4 and Figure 5 is a diagram showing the operation of an electrolyte solution leakage detection device according to an exemplary embodiment.

[0033] Figure 6 is a diagram showing an electrolyte solution leakage detection device according to an exemplary embodiment.

[0034] Figure 7 is a flowchart showing a method for detecting electrolyte solution leakage in a battery device according to an exemplary embodiment.

[0035] Figure 8 is a diagram showing an example of the structure of a battery pack according to an exemplary embodiment. DETAILED DESCRIPTION

[0036] In the following detailed description, only certain exemplary embodiments of the present invention are shown and described by way of illustration. As those skilled in the art will recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the present invention. Thus, the drawings and description are to be regarded as illustrative rather than restrictive. Throughout the specification, the same reference numerals denote the same elements.

[0037] It should be understood that when a component is referred to as being "connected" to another component, it can be directly connected to the other component, or there can be other components therebetween. In contrast, it should be understood that when a component is referred to as being "directly connected" to another component, there are no other components therebetween.

[0038] In the following description, unless a clear expression such as "a", "an", or "single" is used, an expression written in the singular form can be understood as the singular form or the plural form.

[0039] In the flowchart described with reference to the accompanying drawings, the order of operations can be changed, several operations can be combined, operations can be divided, and some operations can be not executed.

[0040] Figure 1 is a diagram showing a battery device according to an exemplary embodiment.

[0041] 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 solution leakage detection circuit 120.

[0042] The battery module 110 may include a plurality of battery cells (not shown in the figure). In an exemplary embodiment, the battery cells may be rechargeable batteries, and these battery cells may include an anode, a cathode, and an electrolyte solution. In an exemplary embodiment, a predetermined number of battery cells may be connected in series or in parallel to form a battery module. In Figure 1 for ease of explanation, one battery module 110 is shown; however, the battery pack 100 may include one or more battery modules 110 to provide desired power.

[0043] The electrolyte solution leakage detection circuit 120 may include an electrolyte solution leakage detection sensor 121 and a battery monitoring circuit 122.

[0044] The electrolyte solution leakage detection sensor 121 may be connected to the battery module 110, and may detect leakage of the electrolyte solution from the battery cells included in the battery module 110, and send a signal to the battery monitoring circuit 122 when the leakage of the electrolyte solution is detected.

[0045] The battery monitoring circuit 122 can be connected to the battery module 110 and monitor the voltage of the battery cells. In an exemplary embodiment, the battery monitoring circuit 122 can also measure the temperature of the battery module 110. In an exemplary embodiment, the battery monitoring circuit 122 can be provided in the form of an integrated circuit (IC). When the battery monitoring circuit 122 receives a signal from the electrolyte solution leakage detection sensor 121, it can transmit the corresponding information to an external device (e.g., a vehicle).

[0046] The battery monitoring circuit 122 can perform communication with the battery management system 10 of the battery device. The battery management system 10 can control the operation of the battery pack 100 by collecting the data (information) sent from the battery monitoring circuit 122. In addition, the battery management system 10 can send the information collected from the battery monitoring circuit 122 to an external device (e.g., a vehicle).

[0047] Figure 2 and Figure 3 are diagrams showing an electrolyte solution leakage detection device according to an exemplary embodiment.

[0048] Referring to Figure 2 , the electrolyte solution leakage detection device 200 can include an electrolyte solution leakage detection sensor 210 and a battery monitoring circuit 220. In an exemplary embodiment, the electrolyte solution leakage detection device 200 can correspond to Figure 1 the electrolyte solution leakage detection circuit 120.

[0049] In an exemplary embodiment, a power supply for providing a predetermined voltage Vs can be generated from the voltage of the battery module (e.g., Figure 1 the reference numeral “110” in the drawings). To this end, the electrolyte solution leakage detection device 200 can further include a voltage regulator 230. The voltage regulator 230 can receive the voltage Vm of the battery module 110 through the input terminal IN and output the predetermined voltage Vs through the output terminal OUT. The voltage Vs can be, for example, 5V.

[0050] The electrolyte solution leakage detection sensor 210 may include a resistor 211 and an electrolyte solution detection unit 212 connected in series between a power supply for providing a predetermined voltage Vs and a ground terminal. The voltage at the contact point of the resistor 211 and the electrolyte solution detection unit 212 may be transferred as a detection voltage to RC filter circuits 213 and 214. The detection voltage may pass through the RC filter circuits 213 and 214, and then be input as a first input voltage Via to a comparison circuit 215. Here, the comparison circuit 215 may be an operational amplifier, and the first input voltage Via may be the voltage applied to the negative input terminal of the operational amplifier. Meanwhile, the electrolyte solution leakage detection sensor 210 may further include a plurality of resistors 216 and 217 connected in series between the power supply for providing the predetermined voltage Vs and the ground terminal. The voltage at the contact point of the plurality of resistors 216 and 217 may be input as a second input voltage Vib to the comparison circuit 215. Here, the second input voltage Vib may be the voltage applied to the positive input terminal of the operational amplifier.

[0051] The second input voltage Vib may be a fixed voltage for causing the operational amplifier to operate as a voltage comparator. For example, the plurality of resistors 216 and 217 may be set to the same resistance value as each other, and the second input voltage Vib may be set to half of the value of the voltage Vs. Thus, when the first input voltage Via applied to the negative input terminal of the operational amplifier has a value greater than the second input voltage Vib, the output voltage Vo of the operational amplifier may have a value corresponding to a low level. On the other hand, when the first input voltage Via applied to the negative input terminal of the operational amplifier has a value less than the second input voltage Vib, the output voltage Vo of the operational amplifier may have a value corresponding to a high level.

[0052] In an exemplary embodiment, when the voltage Vs is set to 5V, the resistors 211, 213, 216, and 217 may be set to 170 kΩ, 10 kΩ, 43 kΩ, and 43 kΩ respectively, and a capacitor 214 having 47 μF may be used.

[0053] When no electrolyte solution leaks from the battery cell, the electrolyte solution detection unit 212 may not form any current path, and when electrolyte solution leaks from the battery cell, a current path may be formed by the leaked electrolyte solution. Referring together Figure 3 to, the electrolyte solution detection unit 212 may include two electrolyte solution detection nodes N1 and N2 formed separately from each other. When electrolyte solution leaks from the battery cell, the first detection node N1 and the second detection node N2 may be electrically connected.

[0054] As Figure 3As shown, when the electrolyte solution is located between the first detection node N1 and the second detection node N2, since the electrolyte solution acts as a resistor having a value similar to that of the resistor 211, when the resistor 211 has been set to 170 kΩ, the same effect as that of connecting a resistor of 170 kΩ in series between the voltage Vs and the ground terminal can be produced. Therefore, the detection voltage at the contact point between the resistor 211 and the electrolyte solution detection unit 212 can drop to a voltage value corresponding to half of the voltage Vs (2.5 V when the voltage Vs is 5 V), which can be applied to the comparison circuit 215 as the first input voltage Via. At this time, the second input voltage Vib of the comparison circuit 215 can be a voltage value corresponding to half of the voltage Vs (2.5 V when the voltage Vs is 5 V). However, although the resistance value of the electrolyte solution is initially 170 kΩ, it gradually decreases with time. Therefore, the second input voltage Vib becomes lower than the voltage value corresponding to half of the voltage Vs. As a result, the value of the first input voltage Via applied to the negative input terminal is less than the value of the second input voltage Vib applied to the positive input terminal. In this case, the output voltage Vo of the comparison circuit 215 can become high level (e.g., 5 V).

[0055] Conversely, when no electrolyte solution leaks from the battery cell, since the first detection node N1 and the second detection node N2 are not electrically connected, the detection voltage at the contact point between the resistor 211 and the electrolyte solution detection unit 212 can become a voltage value corresponding to the voltage Vs (5 V when the voltage Vs is 5 V), and is applied to the comparison circuit 215 as the first input voltage Via. At this time, the second input voltage Vib of the comparison circuit 215 has a voltage value corresponding to half of the voltage Vs (2.5 V when the voltage Vs is 5 V). Therefore, the value of the first input voltage Via applied to the negative input terminal is greater than the value of the second input voltage Vib applied to the positive input terminal. As a result, the output voltage Vo of the comparison circuit 215 can become low level (e.g., 0 V).

[0056] The battery monitoring circuit 220 may receive a signal corresponding to the output voltage Vo of the electrolyte solution leakage detection sensor 210 through an input terminal IN (e.g., an input pin). In an exemplary embodiment, the input terminal IN may be one of various input terminals provided for the battery monitoring circuit 220 to receive monitoring results. In an exemplary embodiment, the electrolyte solution leakage detection device 200 may further include an analog-to-digital converter (ADC) 240 for converting the output voltage Vo of the electrolyte solution leakage detection sensor 210 into a digital signal that the battery monitoring circuit 220 can receive. In an exemplary embodiment, the electrolyte solution leakage detection device 200 may further include a diode D1 to block a current path in the opposite direction (i.e., a current path from the input terminal IN of the battery monitoring circuit 220 to the output terminal of the electrolyte solution leakage detection sensor 210). The anode of the diode D1 may be connected to the output terminal of the electrolyte solution leakage detection sensor 210, and its cathode may be connected to the input terminal IN of the battery monitoring circuit 220.

[0057] The battery monitoring circuit 220 may operate with a predetermined voltage V_BMIC applied to a power supply terminal Vcc (e.g., a power supply pin). In an exemplary embodiment, the predetermined voltage V_BMIC may be the same voltage as the predetermined voltage Vs of the electrolyte solution leakage detection sensor 210. In addition, the battery monitoring circuit 220 may communicate with a battery management system (e.g., Figure 1 the reference numeral “10” in the drawings) through a transmission terminal Tx (e.g., a transmission pin) and a reception terminal Rx (e.g., a reception pin). The battery monitoring circuit 220 may transmit the monitored data to the battery management system 10 through a communication line for transmission connected between the transmission terminal Tx and the battery management system 10, and receive a control signal from the battery management system 10 through a communication line for reception connected between the reception terminal Rx and the battery management system 10. In an exemplary embodiment, the communication between the battery monitoring circuit 220 and the battery management system 10 may be universal asynchronous receiver / transmitter (UART) communication.

[0058] The battery monitoring circuit 220 may transmit information corresponding to the output voltage Vo of the electrolyte solution leakage detection sensor 210 received through the input terminal IN to, for example, the battery management system 10. As described above, when the electrolyte solution does not leak, the output voltage Vo of the electrolyte solution leakage detection sensor 210 is a low-level voltage (e.g., 0V). Therefore, when the output voltage Vo of the electrolyte solution leakage detection sensor 210 is a voltage lower than the reference voltage, a processor of an external device (e.g., a vehicle) or the battery management system 10 may determine that the electrolyte solution does not leak.

[0059] In contrast, when the electrolyte solution leaks, the output voltage Vo of the electrolyte solution leakage detection sensor 210 is a high-level voltage (e.g., 5V). Therefore, when the output voltage Vo of the electrolyte solution leakage detection sensor 210 is higher than the reference voltage, the processor of the external device or the battery management system 10 can determine that the electrolyte solution has leaked. As described above, the battery management system 10 or the external device can detect the leakage of the electrolyte solution in the battery pack through the output signal of the battery monitoring circuit 220 and perform a protection operation. In an exemplary embodiment, when the output voltage Vo is lower than the reference voltage, the battery management system 10 can send a warning signal to an external device (e.g., a vehicle). Thus, the driver of the vehicle can check the battery pack.

[0060] According to this exemplary embodiment, since the resistor 211 is disposed between the power supply and the ground terminal, it is possible to prevent the electrolyte solution detection unit 212 from being directly connected to the power supply, thereby preventing a short circuit between the voltage Vs and the ground terminal, and protecting the battery module 110, the electrolyte solution leakage detection sensor 210, and the battery monitoring circuit 220 by limiting the current. In addition, since the electrolyte solution detection unit 212 is designed to be regarded as an open circuit when the electrolyte solution does not leak, the occurrence of leakage current can be prevented. Further, since the RC filter circuits 213 and 214 are employed, it is possible to prevent misdetection of whether the electrolyte solution leaks due to transient AC noise. Therefore, the detection accuracy can be improved.

[0061] Figure 4 and Figure 5 is a diagram showing the operation of the electrolyte solution leakage detection device according to the exemplary embodiment.

[0062] Referring to Figure 4 and Figure 5 , the time period T1 may correspond to a normal state where no solution leakage occurs. During the time period T1, the first input voltage Via applied to the negative input terminal of the comparison circuit 215 may be 5V (see reference numeral "A"). At this time, the output voltage Vo output from the output terminal of the comparison circuit 215 may be 0V (see reference numeral "E"). Here, the second input voltage Vib applied to the positive input terminal of the comparison circuit 215 may be 2.5V (see reference numeral "D").

[0063] The time period T2 may correspond to a state in which a solution leakage has occurred. When a solution leakage occurs, the first input voltage Via applied to the negative input terminal of the comparison circuit 215 decreases to 2.5V (see reference numeral "B"). Subsequently, as described above, as the resistance value of the electrolyte solution decreases, the first input voltage Via may further decrease to a voltage lower than 2.5V. Accordingly, the output voltage Vo output from the output terminal of the comparison circuit 215 may be 5V (see reference numeral "F").

[0064] The time period T3 may correspond to a normal state after the leaked solution has been removed. During the time period T3, the first input voltage Via applied to the negative input terminal of the comparison circuit 215 may be 5V (see reference numeral "C"). At this time, the output voltage Vo output from the output terminal of the comparison circuit 215 may be 0V (see reference numeral "G").

[0065] Figure 6 FIG. is a diagram illustrating an electrolyte solution leakage detection device according to an exemplary embodiment.

[0066] Referring to Figure 6 , the electrolyte solution leakage detection device 300 may include an electrolyte solution leakage detection sensor 310 and a battery monitoring circuit 320. In an exemplary embodiment, the electrolyte solution leakage detection device 300 may correspond to Figure 1 the electrolyte solution leakage detection circuit 120.

[0067] The electrolyte solution leakage detection sensor 310 may include a resistor 311 and an electrolyte solution detection unit 312 connected in series between a power supply for providing a predetermined voltage Vs and a ground terminal, and the voltage at the contact point of the resistor 311 and the electrolyte solution detection unit 312 may be transmitted as a detection voltage to RC filter circuits 313 and 314. The detection voltage may pass through the RC filter circuits 313 and 314 and then be input as a first input voltage Via to the comparison circuit 315. Meanwhile, the electrolyte solution leakage detection sensor 310 may further include a plurality of resistors 316 and 317 connected in series between a power supply for providing a predetermined voltage Vs and a ground terminal. The voltage at the contact point of the plurality of resistors 316 and 317 may be input as a second input voltage Vib to the comparison circuit 315. In an exemplary embodiment, the electrolyte solution leakage detection device 300 may further include a voltage regulator 330 for generating the predetermined voltage Vs.

[0068] The battery monitoring circuit 320 may receive a signal corresponding to the output voltage Vo of the electrolyte solution leakage detection sensor 310. In an exemplary embodiment, the electrolyte solution leakage detection device 300 may further include an ADC 340 for converting the output voltage Vo of the electrolyte solution leakage detection sensor 310 into a digital signal that can be received by the battery monitoring circuit 320. In an exemplary embodiment, the electrolyte solution leakage detection device 300 may further include a diode D1 to block the current path in the opposite direction.

[0069] In an exemplary embodiment, the battery monitoring circuit 320 may be set to one of an active mode and a shutdown mode. In the active mode, the battery monitoring circuit 320 monitors the battery module (e.g., Figure 1 the reference numeral “110” in the drawings), and in the shutdown mode, the battery monitoring circuit 320 does not monitor the battery module 110. In the active mode, a predetermined voltage V_BMIC is provided to the power terminal Vcc (e.g., the power pin) of the battery monitoring circuit 320 to enable the battery monitoring circuit 320 to operate. In the shutdown mode, the predetermined voltage V_BMIC may be blocked so as not to be provided to the power terminal Vcc of the battery monitoring circuit 320. Accordingly, the battery monitoring circuit 320 may not operate. In an exemplary embodiment, the predetermined voltage V_BMIC may be the same as the predetermined voltage Vs provided to the electrolyte solution leakage detection sensor 310. In an exemplary embodiment, the electrolyte solution leakage detection device 300 may further include a pulse generator 350 such that the electrolyte solution leakage can be detected even when the battery monitoring circuit 320 is in the shutdown mode.

[0070] The output voltage Vo of the electrolyte solution leakage detection sensor 310 may be provided to the input terminal IN of the pulse generator 350. In an exemplary embodiment, the signal obtained by converting the output voltage Vo of the electrolyte solution leakage detection sensor 310 through the ADC 340 may be input to the input terminal IN of the pulse generator 350. In an exemplary embodiment, the electrolyte solution leakage detection device 300 may further include a diode D2 to block 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 solution leakage detection sensor 310). The anode of the diode D2 may be connected to the output terminal of the electrolyte solution leakage detection sensor 310, and its cathode may be connected to the input terminal IN of the pulse generator 350.

[0071] A transistor 351 can be connected between the output terminal OUT and the ground terminal of the pulse generator 350. In other words, the first terminal of the transistor 351 can be connected to the output terminal OUT of the pulse generator 350, and the second terminal of the transistor 351 can be connected to the ground terminal. In addition, the control terminal of the transistor 351 receives the same voltage as the voltage of the power supply terminal Vcc of the battery monitoring circuit 320. For example, the control terminal of the transistor 351 can be connected to the power supply terminal Vcc of the battery monitoring circuit 320. In addition, the first terminal of the transistor 351 can be connected to the transmission terminal Tx (e.g., transmission pin) of the battery monitoring circuit 320. In an exemplary embodiment, the first terminal of the transistor 351 can be connected to a communication line for transmission between the transmission terminal Tx of the battery monitoring circuit 320 and the battery management system (e.g., Figure 1 the reference numeral "10" in). In an exemplary embodiment, the electrolyte solution leakage 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 communication line to the first terminal of the transistor 351). The anode of the diode D3 can be connected to the first terminal of the transistor 351, and its cathode can be connected to the receiving terminal Rx of the battery monitoring circuit 320. In an exemplary embodiment, a resistor 352 can be connected between the output terminal OUT of the pulse generator 350 and the first terminal of the transistor 351.

[0072] When a predetermined voltage (e.g., 5V) is applied to the power supply terminal Vcc of the battery monitoring circuit 320, the transistor 351 can be turned on, and when the voltage is blocked from being applied to the power supply terminal Vcc of the battery monitoring circuit 320, the transistor 351 can be turned off. In an exemplary embodiment, the transistor 351 can be an n-channel transistor, such as an n-channel metal oxide semiconductor field effect transistor (MOSFET). In this case, the first terminal, the second terminal, and the control terminal of the transistor 351 can be the drain, the source, and the gate, respectively.

[0073] In the active mode, the electrolyte solution leakage detection sensor 310 and the battery monitoring circuit 320 operate in the same manner as the electrolyte solution leakage detection sensor 210 and the battery monitoring circuit 220 described with reference to Figure 2 and will not be described herein. Meanwhile, in the active mode, since a predetermined voltage is applied to the power supply terminal Vcc of the battery monitoring circuit 320, the transistor 351 is turned on. Therefore, 0V is applied to the anode of the diode D3, which may not affect the communication through the transmission terminal Tx of the battery monitoring circuit 320.

[0074] In the off mode, the voltage is blocked so as not to be applied to the power supply terminal Vcc of the battery monitoring circuit 320, causing the transistor 351 to be cut off. Further, when the electrolyte solution leaks, since the output voltage Vo is output from the electrolyte solution leakage detection sensor 310, the pulse generator 350 can generate a pulse signal in response to the output voltage Vo of the electrolyte solution leakage detection sensor 310 and output it to the output terminal OUT. In other words, when the voltage input to the input terminal IN of the pulse generator 350 is higher than the threshold voltage, the pulse generator can generate a pulse signal and output it to the output terminal OUT. In this case, since the transistor 351 is cut off, the pulse signal of 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 the 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 solution leakage detection sensor 310 to the battery management system 10.

[0075] In an exemplary embodiment, the transistor 351, the resistor 352, and the diode D3 can transmit the pulse signal of the pulse generator 350 to the transmission terminal Tx of the battery monitoring circuit 320 in the off mode and operate as a transmission circuit that blocks the transmission of the pulse signal in the active mode.

[0076] According to the above exemplary embodiment, even in the off mode, the battery monitoring circuit 320 can detect the leakage of the electrolyte solution.

[0077] Figure 7 is a flowchart showing a method for detecting leakage of an electrolyte solution of a battery device according to an exemplary embodiment.

[0078] Referring to Figure 7 , when the battery monitoring circuit of the battery pack is in the active mode (S710), the battery monitoring circuit measures the voltage corresponding to the leakage of the electrolyte solution (S750). In an exemplary embodiment, the battery monitoring circuit can measure the detection voltage output from the electrolyte solution leakage detection sensor (S750).

[0079] When the battery monitoring circuit of the battery pack is in the off mode, if electrolyte solution leakage occurs in the battery pack (S720), the battery device generates a pulse signal in response to the electrolyte solution leakage (S730). In response to the pulse signal, the battery monitoring circuit switches to the active mode (S740), and measures the voltage corresponding to the electrolyte solution leakage (S750). In an exemplary embodiment, in response to the output voltage of a comparison circuit output by an electrolyte solution leakage detection sensor in response to the electrolyte solution leakage, a pulse generator may generate a pulse signal, and the battery monitoring circuit may switch to the active mode in response to the pulse signal of the pulse generator.

[0080] When the voltage measured by the battery monitoring circuit is higher than the reference voltage (S760), the battery device may diagnose electrolyte solution leakage and transmit a warning signal to an external device (e.g., a vehicle) (S770). When the measured voltage is not higher than the reference voltage, the battery device may diagnose that no electrolyte solution leakage has occurred (S780).

[0081] Now, reference will be made to Figure 8 a battery pack to which an electrolyte solution leakage detection method according to various exemplary embodiments may be applied will be described.

[0082] Figure 8 is a diagram showing an example of the structure of a battery pack according to an exemplary embodiment.

[0083] Referring to Figure 8 , the battery pack 500 may be formed by combining a lower case 510 and an upper case (not shown in the figure), and includes a battery module 520 disposed therein. In Figure 8 , for ease of explanation, the battery pack 500 is shown including four battery modules 520; however, the number of battery modules 520 is not limited thereto. The battery modules 520 are respectively connected to a battery monitoring circuit 530. Each battery monitoring circuit 530 may monitor the battery cell voltage, temperature, etc. of the corresponding battery module 520.

[0084] Below each battery module 520, a lower cover 540 may be formed. Each lower cover 540 may have a shape capable of collecting the electrolyte solution leaked in the corresponding battery module 520. An electrolyte solution leakage detection sensor 550 may be attached to each lower cover 540. Each electrolyte solution leakage detection sensor 550 may sense the electrolyte solution collected in the lower cover 540 and output a corresponding voltage.

[0085] In an exemplary embodiment, the inner cover 560 of the battery pack may be formed on the lower housing 510. The inner cover 560 of the battery pack may be formed between the lower housing 510 and the lower cover 540. The inner cover 560 of the battery pack may be formed of a non-conductive material to block a current path to the lower housing 510 that may be formed by a leaked electrolyte solution.

[0086] Although the present invention has been described in connection with exemplary embodiments that are presently considered to be practical, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A battery pack, the battery pack comprises: a battery module, the battery module including a plurality of battery cells; a battery monitoring circuit, the battery monitoring circuit being connected to the battery module and monitoring the battery module; and an electrolyte solution leakage detection sensor, the electrolyte solution leakage detection sensor detecting the electrolyte solution leaked in the battery module, wherein, the electrolyte solution leakage detection sensor includes: a first resistor and an electrolyte solution detection unit, the first resistor and the electrolyte solution detection unit being connected in series between a power supply for providing a first voltage and a ground terminal; a second resistor and a third resistor, the second resistor and the third resistor being connected in series between the power supply and the ground terminal; and a comparison circuit, the comparison circuit receiving the detection voltage at the contact point of the first resistor and the electrolyte solution detection unit as a first input voltage, and receiving the voltage at the contact point of the second resistor and the third resistor as a second input voltage, and transmitting an output voltage to an input terminal of the battery monitoring circuit.

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

3. The battery pack according to claim 2, wherein: when the output voltage is higher than a reference voltage, it is diagnosed that the electrolyte solution in the battery module leaks.

4. The battery pack according to claim 1, wherein: the electrolyte solution 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, it is diagnosed that the electrolyte solution in the battery module leaks.

5. The battery pack according to claim 1, the battery pack further comprises: an RC filter circuit, the RC filter circuit receiving the detection voltage at the contact point of the first resistor and the electrolyte solution detection unit, and transmitting the detection voltage to the comparison circuit.

6. The battery pack according to claim 1, the battery pack further comprises: a voltage regulator, the voltage regulator generating the first voltage according to the voltage of the battery module.

7. The battery pack according to claim 1, the battery pack further comprises: the lower housing of the battery pack; and a lower cover, the lower cover being formed on the lower housing, being formed below the battery module, collecting the electrolyte solution leaked in the battery module, and the electrolyte solution leakage detection sensor being attached to the lower cover.

8. The battery pack according to claim 1, wherein: the battery monitoring circuit monitors the battery module in an active mode.

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

10. A battery device, the battery device comprising: A battery module including a plurality of battery cells; A battery monitoring circuit connected to the battery module and monitoring the battery module; An electrolyte solution leakage detection sensor that detects electrolyte solution leaking in the battery module; and A battery management system that manages the battery monitoring circuit and diagnoses leakage of the electrolyte solution by receiving information from the battery monitoring circuit, wherein the electrolyte solution leakage detection sensor includes an electrolyte solution detection unit whose resistance value changes in response to the electrolyte solution leaking in the battery module, and transmits an output voltage of a comparison circuit determined based on the resistance value of the electrolyte solution detection unit to an input terminal of the battery monitoring circuit.

11. The battery device according to claim 10, wherein: When it is determined based on information transmitted from the battery monitoring circuit that the output voltage is higher than a reference voltage, the battery management system diagnoses that the electrolyte solution has leaked in the battery module.

12. The battery device according to claim 10, wherein: The electrolyte solution leakage detection sensor includes the following: A first resistor and the electrolyte solution detection unit, the first resistor and the electrolyte solution detection unit being connected in series between a power supply for providing a first voltage and a ground terminal; A second resistor and a third resistor, the second resistor and the third resistor being connected in series between the power supply and the ground terminal; and A comparison circuit that receives a detection voltage at a contact point of the first resistor and the electrolyte solution detection unit as a first input voltage, and receives a voltage at a contact point of the second resistor and the third resistor as a second input voltage, and transmits an output voltage to an input terminal of the battery monitoring circuit.

13. The battery device according to claim 12, the battery device further comprising: A pulse generator that transmits a pulse signal to a transmission terminal of the battery monitoring circuit when the electrolyte solution leakage detection sensor detects leakage of the electrolyte solution in the battery module in a shutdown mode of the battery monitoring circuit, wherein the battery monitoring circuit transitions to an active mode in response to the pulse signal.

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

15. The battery device according to claim 13, the battery device further comprising: A transistor, the transistor being connected between an output terminal and a ground terminal of the pulse generator and controlling transmission of the pulse signal to a transmission terminal of the battery monitoring circuit in response to a voltage supplied to a power supply terminal of the battery monitoring circuit.

16. The battery device according to claim 15, wherein: In the active mode, a second voltage is supplied to the power supply terminal of the battery monitoring circuit, and in the shutdown mode, the second voltage is blocked so as not to be supplied to the power supply terminal of the battery monitoring circuit, and the transistor is turned on in response to the second voltage in the active mode to block transmission of the pulse signal, and is turned off in response to the blocking of the second voltage in the shutdown mode to transmit the pulse signal.

17. The battery device according to claim 10, the battery device further comprising: A lower cover, the lower cover being formed below the battery module, collecting the electrolyte solution leaked in the battery module, and an electrolyte solution leakage detection sensor being attached to the lower cover.

18. A method for detecting leakage of an electrolyte solution of a battery device, the battery device including a battery module, a battery monitoring circuit for monitoring the battery module, and an electrolyte solution leakage detection sensor, the method comprising the following steps: Generating a pulse signal when the electrolyte solution leaks in the battery module while the battery monitoring circuit is in the shutdown mode; Switching the battery monitoring circuit to the active mode in response to the pulse signal; Allowing the electrolyte solution leakage detection sensor to measure an output voltage based on a resistance value that changes in response to the leakage of the electrolyte solution; and When the output voltage is higher than a reference voltage, allowing the battery monitoring circuit in the active mode to diagnose leakage of the electrolyte solution.

19. The electrolyte solution leakage detection method according to claim 18, wherein: The step of measuring the output voltage includes the following steps: Receiving a detection voltage of a contact point of a first resistor and an electrolyte solution detection unit as a first input voltage; Receiving a voltage of a contact point of a second resistor and a third resistor as a second input voltage; and Comparing the first input voltage and the second input voltage, outputting a high-level voltage when the first input voltage is less than the second input voltage, and outputting a low-level voltage when the first input voltage is greater than the second input voltage.

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