Method and system for detecting electrical leakage

Abstract

According to one or more embodiments, an electrical energy storage system is provided. The system includes a plurality of electrochemical cells, a housing frame configured to house the plurality of electrochemical cells therein, and a sensing module configured to detect leakage between the plurality of electrochemical cells and the housing frame. The sensing module may include a current limiter electrically coupled to one or more cathodes or anodes of the electrochemical cells and the housing frame, and an ammeter configured to measure the current between the current limiter and the electrochemical cells. The system may include a circuit powered by an isolated power supply to measure the voltage generated by the leakage current flowing through the current limiter.

Description

[Technical Field]

[0001] Cross-reference of related applications

[0001] This application claims priority to U.S. Patent Application No. 62 / 642,516, filed on 3 May 2024, the entire contents of which are incorporated herein by reference.

[0002] Field of Invention

[0002] This disclosure relates to a power source including a rechargeable lithium-ion battery (e.g., an electrochemical energy storage device), and more particularly to a system, device, and method for detecting leakage current from a power source. [Background technology]

[0003] background

[0003] Power sources, such as battery units for supplying power to electric vehicles, are electrically isolated from the battery (or commonly called an electrochemical cell) container or housing frame and the vehicle in which the battery resides. An insulation failure in either the wiring or a chemical leak of the electrolyte from any battery component such as the battery cell can potentially result in a dangerous voltage to the housing frame, which is usually a metal frame, with respect to the anode or cathode of the battery. Therefore, there is a need for a method, device, or system for detecting an dielectric breakdown (e.g., leakage) between the power source, i.e., the battery, and the housing frame that houses the battery.

[0004] Brief explanation of the drawing

[0004] In order to fully understand the principles and advantages disclosed herein, the following description should be read in conjunction with the accompanying drawings. [Brief explanation of the drawing]

[0005] [Figure 1]

[0005] An embodiment of an electrical energy storage system as a battery module, according to various embodiments, is shown. [Figure 2]

[0006] Circuit models of leakage current in electrical energy storage systems according to various embodiments are illustrated. [Figure 3]

[0007] Circuit models of leak detection mechanisms in electrical energy storage systems, according to various embodiments, are shown. [Figure 4]

[0008] This is a circuit diagram showing one embodiment of a current limiter in an electrical energy storage system, according to various embodiments. [Figure 5]

[0009] This is a circuit diagram showing one embodiment of a sensing module having a leak detection mechanism in an electrical energy storage system, according to various embodiments. [Figure 6]

[0010] This is a circuit diagram showing another embodiment of a sensing module having a leak detection mechanism in an electrical energy storage system, according to various embodiments. [Figure 7]

[0011] Methods for detecting leaks in electrical energy storage systems, according to various embodiments, are illustrated. [Figure 8]

[0012] Figures 1, 2, 3, 4, 5, and 6 illustrate various embodiments of the electrical energy storage systems, and Figure 7 illustrates a block diagram of the processor (computer system) used in the method. [Modes for carrying out the invention]

[0006]

[0013] It should be understood that the drawings are not necessarily drawn to actual size, and the objects in the drawings are not drawn to actual size relative to each other. The drawings are intended to clarify and facilitate understanding of the various embodiments of the apparatus, systems, and methods disclosed herein. Wherever possible, the same reference numerals are used throughout the drawings to refer to the same or similar parts. Furthermore, it should be understood that the drawings are not intended in any way to limit the scope of this instruction.

[0007] Detailed explanation

[0014] The following is a detailed description of the drawings provided for the purpose of illustrating preferred embodiments of the present invention and is not intended to limit preferred embodiments of the present invention. According to various embodiments, systems and methods for detecting leakage current are provided. In particular, systems, devices and methods for detecting breakdown of electrical insulation in an electrochemical energy storage device having a housing or frame containing the electrochemical energy storage device are provided. In one or more embodiments, the disclosed system may include a plurality of electrochemical cells and a housing frame configured to house the electrochemical cells within the housing frame. In one or more embodiments, the system may include a sensing module including a current limiter and an ammeter, the current limiter may be electrically coupled to the cathode or anode of one or more of the electrochemical cells and the housing frame. The ammeter may be used to measure the current between the current limiter and the plurality of electrochemical cells. According to various embodiments, the sensing module in the system may be configured to detect leakage, e.g., leakage current, between one or more of the electrochemical cells and the housing frame.

[0008]

[0015] In one or more embodiments, a method for detecting leakage current may include connecting a current limiter between the housing frame and the anode (or cathode) of the electrochemical cell, so that leakage current can flow from the electrochemical cell to the housing frame. The method may also include measuring the leakage current to determine the degree of leakage. In various embodiments, the leakage current may be measured at both the anode and cathode connections. In one or more embodiments, the exact location of the leakage, i.e., dielectric breakdown, may be unknown. According to one or more embodiments, the disclosed system / method may be configured to detect leakage currents of less than 2 milliamperes (mA).

[0009]

[0016] Figure 1 illustrates one embodiment of an electrical energy storage system 100, such as a battery module, according to various embodiments. As shown in Figure 1, the electrical energy storage system 100 includes, according to one or more embodiments, one or more electrochemical cells 116 connected in series and / or parallel, housed inside a housing frame 112 (hereinafter referred to herein as housing, frame, or simply enclosure), and sealed by a lid 114 (removable or otherwise). In some embodiments, the electrical energy storage system 100 includes electrochemical cells 116 connected in series by one or more busbars 118 located in the housing frame 112. As shown in Figure 1, the electrical energy storage system 100 includes inter-cell connections 120 (to one or more anodes and cathodes of the electrochemical cells 116) and a cable assembly 122, which can be configured to provide access to individual electrochemical cells 116 for, for example, measuring the voltage and / or temperature of the cells. In one or more embodiments, the cell connection 120 needs to be insulated from the housing frame 112 and lid 114 in the electrical energy storage system 100. In some scenarios, an insulation failure (i.e., dielectric breakdown) may occur between the housing frame 112 and / or lid 114 and the electrochemical cell 116. This dielectric breakdown or leakage may occur through an electrical short circuit or fluid leakage in one of the connection 120, for example, leakage of electrolyte from one of the electrochemical cells 116. In one or more embodiments, dielectric breakdown may result in a loss of electrical insulation between the electrochemical cell 116 and the housing frame 112 and / or lid 114.

[0010]

[0017] Figure 2 illustrates circuit models of leakage current in an electrical energy storage system 200 according to various embodiments. As depicted in Figure 2, the electrical energy storage system 200 includes a plurality of electrochemical cells 216 housed within a housing frame 212. The circuit model shown in Figure 2 illustrates leakage current 230 between the plurality of electrochemical cells 216 and the housing frame 212. In the case of the plurality of electrochemical cells 216, the resistance can be shown as having a potential designated as Vb 214 with respect to ground designated as Com 218, and the loss of insulation occurs in any part of the electrical energy storage system 200. In other words, the leakage current to the housing frame 212 originates from any point in the stack of the plurality of cells 216 that forms the supply voltage Vb of the “battery”, and the leakage is through a single resistance R from the point from the cathode of the bottom cell to the anode of the top cell to the frame 212, as shown in Figure 2. Leakge Assume that it can be expressed as follows: If k ∈ [0,1] represents the location where insulation is lost (i.e., a leakage current occurs) within the electrical energy storage system 200, then k*Vb can be specified as the relevant voltage (with respect to cathode Com 218) that drives the leakage current. Thus, the relevant voltage (with respect to anode Vb 214) is expressed as (1-k)*Vb. The leakage current 230 represents the degree of insulation or leakage compromise between the multiple electrochemical cells 216 and the frame 212, R Leakge It can be displayed as follows.

[0011]

[0018] Figure 3 shows circuit models of leakage detection mechanisms in an electrical energy storage system 300 according to various embodiments. As illustrated in Figure 3, the electrical energy storage system 300 includes a plurality of electrochemical cells 316 housed within a housing frame 312. The circuit model shown in Figure 3 illustrates a leakage current 330 between the plurality of electrochemical cells 316 and the housing frame 312. As described in Figure 2, for the plurality of electrochemical cells 316, the resistance can be shown as having a potential specified by Vb314 with respect to ground specified by Com318, and the loss of insulation occurs in any part of the electrical energy storage system 300. If k∈[0,1] represents the location where insulation is lost (i.e., a leakage current occurs) within the electrical energy storage system 300, then k*Vb can be specified as the relevant voltage (with respect to cathode Com318) that drives the leakage current. Similarly, the relevant voltage (with respect to anode Vb314) is shown as (1-k)*Vb. The leakage current 330 represents the degree of insulation or leakage compromise between the multiple electrochemical cells 316 and the frame 312, R Leakge It can be displayed as follows.

[0012]

[0019] As further illustrated in Figure 3, the electrical energy storage system 300 further includes a sensing module 340 coupled to a plurality of electrochemical cells 316 via relay switches S1 346 and S2 348. The sensing module 340 further includes a frame 312 and a current limiter 342 and an ammeter 344 connected in series between the frame 312 and either the anode or cathode of the plurality of electrochemical cells 316, as depicted in Figure 3. When either S1 346 or S2 348 is closed, the circuit is completed or closed, allowing leakage current to flow from the plurality of electrochemical cells 316 to the frame 312, which can then be measured by the ammeter 344. According to one or more embodiments, the current limiter 342 has at least two functions: namely, R LeakgeIt limits the amount of current that may be generated when the current is small, and when the switch (either S1 346 or S2 348) is closed, the circuit itself is a leakage path to frame 312, thus functioning as a current limiting source at a safe level (according to industry standards such as, but not limited to, UL60950).

[0013]

[0020] Figure 4 is a circuit diagram showing one embodiment of a current limiter 442 in an electrical energy storage system 400 according to various embodiments. As shown in Figure 4, the electrical energy storage system 400 includes a sensing module 440 coupled to a plurality of electrochemical cells 316. The sensing module 440 includes a current limiter 442, which can be a bidirectional current limiter incorporating a current measuring element according to one or more embodiments of this specification. In one or more embodiments, as depicted in Figure 4, the current limiter 442 is electrically coupled to a housing frame 412 and a plurality of electrochemical cells 416. The current limiter 442 includes a first depletion-layer metal oxide semiconductor field-effect transistor (MOSFET) Q1 451 and a second depletion-layer MOSFET Q2 452, as shown in Figure 4. In one or more embodiments, Q1 451 and Q2 452 can be N-channel MOSFETs.

[0014]

[0021] MOSFET Q1 451 has a Q1 source 451-s and a Q1 gate 451-g, and MOSFET Q2 451 has a Q2 source 452-s and a Q2 gate 452-g. In some embodiments, as shown in FIG. 4, the Q1 source 451-s of MOSFET Q1 451 and the Q2 source 452-s of MOSFET Q2 452 are electrically connected to each other via R1 and R2. The gates (Q1 gate 451-g and Q2 gate 452-g) of each transistor MOSFET Q1 451 and MOSFET Q2 452 are connected to the source of the other transistor. When current flows through the current limiter 442, a voltage is generated between R1 and R2, and when the voltage becomes large enough, i.e., when the leakage current becomes large enough, according to one or more embodiments described herein, one of the transistors of MOSFET Q1 451 or MOSFET Q2 452 turns off and limits the current flow. In one or more embodiments, the direction of the (leakage) current flow determines which transistor, MOSFET Q1 451 or MOSFET Q2 452, turns off. In some embodiments, the current can be limited to Vt / (R1+R2), where Vt in the formula is the threshold voltage of MOSFET Q1 451 or Q2 452. The leakage current is V Leakage Since it can be directly estimated by measuring the voltage across R1 designated as 430, a current sensing element of a current meter (not shown here), such as the current meter 344 in FIG. 3, is originally incorporated in the current limiter 442. Generally, (R1+R2) is selected to limit the current to a safe level (e.g., according to industry standards such as UL60950, but not limited thereto), and R1 is selected to provide a V / A gain compatible with the input voltage range of the voltage measurement mechanism, for example, via analog-to-digital conversion, as disclosed herein with respect to FIG. 4.

[0015]

[0022] Figure 5 is a circuit diagram showing one embodiment of a sensing module 540 having a leak detection mechanism in an electrical energy storage system 500, according to various embodiments. As shown in Figure 5, the electrical energy storage system 500 includes a sensing module 540 coupled to a plurality of electrochemical cells 516 provided within a housing frame 512. The sensing module 540 includes a current limiter 542, which can be a bidirectional current limiter incorporating a current measuring element, according to one or more embodiments of this specification with respect to Figure 5. As shown, according to one or more embodiments, Q1 551, R1, R2, and Q2 552 are connected in series to form a current limiter 542 that electrically connects the frame 512 and the plurality of cells 516, and to the anode Vb 514 or cathode Com 518 of the cells 516, via solid-state relays S1 546 and S2 548. The frame end of R1 is biased to Vref, which is generated by resistive voltage dividers Rt and Rb supplied from a power supply having an isolated output called an isolated output power supply 570, as shown in Figure 5. In one or more embodiments, Vref can be set to half of the supply voltage, and if the power supply is grounded at one end, it becomes possible to measure a negative current.

[0016]

[0023] As further illustrated in Figure 5, U1 561 is an amplifier operating from an isolated output power supply 570. As illustrated in Figure 5, the sensing module 540 may, in one or more embodiments, include a highly linear analog optocoupler U2-A with well-matched photodiodes U2-B and U2-C. During operation, in one or more embodiments, the voltage VLEAKAGE across R1 is applied across R4 by driving U2-A to generate sufficient current in U2-B (U1, U2-B, R3, and R4 form a servo mechanism). The same current can flow through U2-C, thereby providing an analog-to-digital (AtoD) input (V LEAKIt is possible to generate the voltage supplied to (), which can be scaled by the value of R5 in one or more embodiments. In some embodiments, R5 can be set such that when no leakage current can flow, for example, when S1 546 and S2 548 are open, the voltage across R5 is half of the AtoD input voltage range.

[0017]

[0024] In one or more embodiments, using a processor configured to control S1 546, S2 548, and the AtoD converter, in the state where S1 546 and S2 548 are open, the state where S1 546 is closed and S2 548 is open, and the state where S1 546 is open and S2 548 is closed, V LEAK is measured, and by knowing the values of R1, R4, and R5 in advance, ILEAKAGE can be calculated. Specifically, the sensing module 540 can be configured to detect the leakage current between the plurality of electrochemical cells 516 and the housing frame 512 through the following algorithm, which the algorithm may include is as follows. 1. Measure V LEAK in the state where S1 and S2 are open. Call this Vo. 2. Measure V LEAK in the state where S1 is closed and S2 is open. Call this VH. 3. Measure V LEAK in the state where S1 is open and S2 is closed. Call this VL. 4. Calculate IH = (VH - Vo) * R4 / (R1 * R5). 5. Calculate IL = (VL - Vo) * R4 / (R1 * R5). 6. If the magnitude of IH or IL exceeds the maximum allowable leakage current threshold, declare a leakage error.

[0018]

[0025] Figure 6 is a schematic diagram showing another embodiment of a sensing module 640 having a leak detection mechanism in an electrical energy storage system 600 according to various embodiments. As shown in Figure 6, the electrical energy storage system 600 includes a sensing module 640 coupled to a plurality of electrochemical cells 616 provided within a housing frame 612. The sensing module 640 includes a current limiter 642, which can be a bidirectional current limiter incorporating a current measuring element according to one or more embodiments herein with respect to Figure 6. As shown, Q1 651, R1, R2, and Q2 652 are connected in series according to one or more embodiments to form a current limiter 642 that electrically connects the frame 612 and the plurality of cells 616, and to the anode Vb 614 or cathode Com 618 of the cells 616 via solid-state relays S1 646 and S2 648. The frame end of R1 is biased to Vref, generated by resistive voltage dividers Rt and Rb, which are powered by a power supply having an isolated output called an isolated output power supply 670, as shown in Figure 6. In one or more embodiments, Vref can be set to half of the supply voltage, making it possible to measure negative current if the power supply is grounded at one end. As further shown in Figure 6, the AtoD converter 680 is directly connected to VLEAKAGE and controlled by the processor via an isolated interface such as an SPI isolator 682.

[0019]

[0026] Examples of components selected for the sensing module 540 or 640 may include the following criteria: • Allowable leakage current: 200μA (Is this too high or too low?) • AtoD input range: 0~2.5V (current processor with VREF at 2.5V) • Operational amplifier: OPA376-Q1 10 picoA input current, maximum 25 microV, maximum offset current • Optocoupler: HCNR201 Maximum mismatch between photodiodes: 7% • Bias resistors: Set to 1kΩ each for a bias voltage of 2.5V. • Current limit set to a maximum of 1mA (for safety). Vt∈[-2.0,-4.0]⇒R1+R2=4 / 1mA=4k For a voltage of 3V / mA, select R1=3k00. Therefore, R2=4k-3k=1k00. • Select R3 = 100Ω (for driving the large current required for the LEDs) Select R4=100k0 (arbitrary). • When leakage current is zero, set V5 to 1.25 volts ⇒ R5 = 1 / 2R4 = 49k9 All resistors have a tolerance of 1% or less. The ideal gain using the above values ​​is R4 / (R1*R5) = 667 μA / V at the A / D input. The error is approximately ±10%.

[0020]

[0027] In some embodiments, the linear optocouplers disclosed above may have mismatches of 7% or more between photodiodes. To eliminate the optocoupler, a differential AtoD converter can be moved into the circuit to transmit AtoD data and control signals via isolation means. AtoD converters with an SPI interface are readily available, as are SPI isolators such as the SPI isolator 682, which improves measurement accuracy, as shown in Figure 6.

[0021]

[0028] According to various embodiments, electrical energy storage systems such as electrical energy storage systems 100, 200, 300, 400, 500, and 600 are described with respect to Figures 1, 2, 3, 4, 5, and 6, respectively, as disclosed herein. The electrical energy storage system may include a plurality of electrochemical cells and a housing frame configured to house the plurality of electrochemical cells therein. In one or more embodiments, such a system may include a sensing module including a current limiter and an ammeter. In one or more embodiments, the current limiter may be electrically coupled to one or more cathodes or anodes of the plurality of electrochemical cells and the housing frame. In one or more embodiments, the ammeter may be configured to measure the current between the current limiter and the plurality of electrochemical cells.

[0022]

[0029] In one or more embodiments, the sensing module may be configured to detect leakage between a plurality of electrochemical cells and a housing frame. In one or more embodiments, the sensing module may further include a first relay switch S1 and a second relay switch S2. In one or more embodiments, the current limiter may be connected via S1 to one or more cathodes of the plurality of electrochemical cells. In one or more embodiments, the current limiter may be connected via S2 to one or more anodes of the plurality of electrochemical cells. In one or more embodiments, each of the plurality of electrochemical cells may be connected to each other in series. In one or more embodiments, S1 may be connected to a first electrochemical cell of the plurality of electrochemical cells, and S2 may be connected to a second electrochemical cell of the plurality of electrochemical cells.

[0023]

[0030] In one or more embodiments, the current limiter may be a bidirectional current limiter circuit including a first depletion-layer metal oxide semiconductor field-effect transistor (MOSFET) Q1 and a second depletion-layer MOSFET Q2. In one or more embodiments, the MOSFETs may be N-channel MOSFETs. In one or more embodiments, Q1 includes a Q1 source and a Q1 gate, Q2 includes a Q2 source and a Q2 gate, and the bidirectional current limiter circuit further includes a first resistor R1 and a second resistor R2, the Q1 source being connected in series to the Q2 source via R1 and R2, so that the Q1 source, R1, R2, and Q2 source are connected in series, the Q1 gate is connected to the Q2 source, and the Q2 gate is connected to the Q1 source.

[0024]

[0031] In one or more embodiments, the electrical energy storage system may further include a reference bias circuit powered by an isolated power supply, and the bidirectional current limiter circuit is biased to a reference voltage via the reference bias circuit powered by the isolated power supply. In one or more embodiments, the reference bias circuit may include two resistive voltage dividers Rt and Rb configured to adjust the reference voltage.

[0025]

[0032] In one or more embodiments, the sensing module may be further configured to detect leakage between a plurality of electrochemical cells and a housing frame via a plurality of leakage voltage measurements performed in the open state of S1 and S2, the closed state of S1 and S2 open, and the open state of S1 and S2 closed.

[0026]

[0033] Referring here to Figure 7, a method S100 for detecting leaks in an electrical energy storage system according to various embodiments, such as systems 100, 200, 300, 400, 500, and 600, is illustrated. As shown in Figure 7, method S100 includes, in step S110, providing a sensing module coupled to the cathode or anode of a plurality of electrochemical cells, such as cells 116, 216, 316, 416, 516, and 616, and a housing frame configured to accommodate the plurality of electrochemical cells, such as frames 112, 212, 312, 412, 512, and 612. In various embodiments, the sensing module may include sensing modules such as sensing modules 340, 440, 540, and 640. The sensing module may include current limiters such as current limiters 342, 442, 542, and 642, and a first relay switch S1 and a second relay switch S2, wherein the current limiters are connected via S1 to the cathodes of one or more of the multiple electrochemical cells and via S2 to the anodes of one or more of the multiple electrochemical cells, each of the multiple electrochemical cells being connected to each other in series, with S1 connected to the first electrochemical cell of the multiple electrochemical cells and S2 connected to the second electrochemical cell of the multiple electrochemical cells.

[0027]

[0034] Method S100 further includes, in step S120, sensing a leakage current between the housing frame and a plurality of electrochemical cells; in step S130, comparing the leakage current with a threshold current value; and in step S140, determining that there is leakage from the plurality of electrochemical cells to the housing frame if the leakage current exceeds the threshold current value. In various embodiments of Method S100, the current limiter is a bidirectional current limiter circuit having a first depletion layer metal oxide semiconductor field-effect transistor (MOSFET) Q1 and a second depletion layer MOSFET Q2. In various embodiments of method S100, Q1 includes a Q1 source and a Q1 gate, Q2 includes a Q2 source and a Q2 gate, the bidirectional current limiter circuit further includes a first resistor R1 and a second resistor R2, the Q1 source is connected in series with the Q2 source via R1 and R2, so that the Q1 source, R1, R2, and Q2 source are connected in series, the Q1 gate is connected with the Q2 source, and the Q2 gate is connected with the Q1 source.

[0028]

[0035] Method S100 may optionally further include, in step S150, biasing a bidirectional current limiter circuit to a reference voltage via a reference bias circuit powered by an isolated power supply. In various embodiments of Method S100, the reference bias circuit may include two resistive voltage dividers Rt and Rb configured to adjust the reference voltage. In various embodiments of Method S100, sensing leakage current between a plurality of electrochemical cells and a housing frame may include performing a plurality of leakage voltage measurements performed with S1 and S2 open, S1 closed and S2 open, and S1 open and S2 closed.

[0029]

[0036] Figure 8 illustrates block diagrams of the processor (computer system 800) used in the electrical energy storage systems 100, 200, 300, 400, 500, and 600 of Figures 1, 2, 3, 4, 5, and 6, and the method of Figure 7, according to various embodiments. The computer system 800 can be used as the processor in the electrical energy storage systems 100, 200, 300, 400, 500, and 600 of Figures 1, 2, 3, 4, 5, and 6, and the method of Figure 7, as will be further described below with respect to Figure 8.

[0030]

[0037] In one or more examples, the computer system 800 may include a bus 802 or other communication mechanism for communicating information, and a processor 804 coupled to the bus 802 for processing information. In various embodiments, the computer system 800 may also include memory, which may be random access memory (RAM) 806 or other dynamic storage device, coupled to the bus 802 for determining instructions to be executed by the processor 804. The memory may also be used to store temporary numerical variables or other intermediate information during the execution of instructions by the processor 804. In various embodiments, the computer system 800 may further include read-only memory (ROM) 808 or other static storage device coupled to the bus 802 for storing static information and instructions for the processor 804. A storage device 810, such as a magnetic disk or optical disk, may be provided and coupled to the bus 802 for storing information and instructions.

[0031]

[0038] In various embodiments, the computer system 800 may be coupled via busbars 802 to a display 812, such as a cathode ray tube (CRT), liquid crystal display (LCD), or light-emitting diode (LED), for displaying information to the computer user. An input device 814, including alphanumeric and other keys, may be coupled to busbars 802 to communicate information and command selections to the processor 804. Another type of user input device is a cursor control 816, such as a mouse, joystick, trackball, gesture input device, gaze-based input device, or cursor direction keys, for communicating directional information and command selections to the processor 804 and for controlling cursor movement on the display 812. This input device 814 typically has two degrees of freedom on two axes, namely a first axis (e.g., x) and a second axis (e.g., y), which allow the device to specify a position in a plane. However, it should be understood that input devices 814 that enable three-dimensional (e.g., x, y, and z) cursor movement are also contemplated herein.

[0032]

[0039] In accordance with a particular implementation of this teaching, the computer system 800 can provide results in response to a processor 804 executing one or more sequences of one or more instructions contained in RAM 806. Such instructions can be read into RAM 806 from another computer-readable medium or computer-readable storage medium, such as a storage device 810. By executing the sequence of instructions contained in RAM 806, the processor 804 can be made to execute the process described herein. Alternatively, this teaching can be implemented using hardwired circuits instead of, or in combination with, software instructions. Therefore, the implementation of this teaching is not limited to any particular combination of hardware circuits and software.

[0033]

[0040] The term “computer-readable medium” (e.g., data store, data storage device, storage device, etc.) or “computer-readable storage medium” as used herein refers to any medium involved in providing instructions to processor 804 for execution. Such mediums may take many forms, including but not limited to non-volatile media, volatile media, and transmission media. Examples of non-volatile media include, but are not limited to, optical disks, solid-state disks, and magnetic disks, such as storage device 810. Examples of volatile media include, but are not limited to, dynamic memory, such as RAM 806. Examples of transmission media include, but are not limited to, coaxial cables, copper wires, and optical fibers, including wires, such as busbar 802.

[0034]

[0041] Common forms of computer-readable media include, for example, floppy disks, flexible disks, hard disks, magnetic tapes, or any other magnetic media, CD-ROMs, any other optical media, punch cards, paper tapes, any other physical media having a pattern of holes, RAM, PROMs, and EPROMs, FLASH-EPROMs, any other memory chips or cartridges, or any other tangible media from which a computer can read.

[0035]

[0042] In addition to computer-readable media, instructions or data may be provided as signals on a transmission medium included in a communication device or system to provide a sequence of one or more instructions to the processor 804 of the computer system 800 for execution. For example, a communication device may include a transceiver having signals indicating instructions and data. The instructions and data are configured to cause one or more processors to implement the functions outlined in this disclosure. Typical examples of data communication transmission connections include, but are not limited to, telephone modem connections, wide area networks (WANs), local area networks (LANs), infrared data connections, NFC connections, optical communication connections, and so on.

[0036]

[0043] It should be understood that the methodologies, flowcharts, figures, and accompanying disclosures described herein can be implemented using the computer system 800 as a standalone device or on a distributed network of shared computing resources, such as a cloud computing network.

[0037]

[0044] The methodologies described herein can be implemented by various means depending on the application. For example, these methodologies can be implemented in hardware, firmware, software, or any combination thereof. In hardware implementations, the processing unit can be implemented in one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, electronic devices, other electronic units designed to perform the functions described herein, or a combination thereof.

[0038]

[0045] In various embodiments, the methods described herein can be implemented as firmware and / or software programs and applications written in conventional programming languages ​​such as C, C++, Python, etc. When implemented as firmware and / or software, the embodiments described herein can be implemented on a non-temporary computer-readable medium in which a program for causing a computer to perform the methods described above is stored. The various engines described herein can be provided on a computer system such as computer system 800, so that the processor 804 receives instructions provided by one or a combination of memory components RAM 806, ROM, 808, or storage devices 810, and user input provided via input device 814, and performs the analysis and determination provided by these engines.

[0039] Detailed description of the embodiment

[0046] Embodiment 1. An electrical energy storage system comprising a plurality of electrochemical cells, a housing frame configured to house the plurality of electrochemical cells therein, and a sensing module including a current limiter and an ammeter, wherein the current limiter is electrically coupled to the cathode or anode of one or more of the plurality of electrochemical cells, the housing frame and ammeter are configured to measure the current between the current limiter and the plurality of electrochemical cells, and the sensing module is configured to detect leakage between the plurality of electrochemical cells and the housing frame.

[0040]

[0047] Embodiment 2. The electrical energy storage system according to Embodiment 1, wherein the sensing module further includes a first relay switch S1 and a second relay switch S2, and a current limiter is connected via S1 to the cathode of one or more of the electrochemical cells, and a current limiter is connected via S2 to the anode of one or more of the electrochemical cells.

[0041]

[0048] Embodiment 3. An electrical energy storage system according to Embodiment 2, wherein each of a plurality of electrochemical cells is connected to one another in series, S1 is connected to a first electrochemical cell among the plurality of electrochemical cells, and S2 is connected to a second electrochemical cell among the plurality of electrochemical cells.

[0042]

[0049] Embodiment 4. An electrical energy storage system according to any one of Embodiments 1 to 3, wherein the current limiter is a bidirectional current limiter circuit including a first depletion-layer metal oxide semiconductor field-effect transistor (MOSFET) Q1 and a second depletion-layer MOSFET Q2.

[0043]

[0050] Embodiment 5. An electrical energy storage system according to Embodiment 4, wherein Q1 includes a Q1 source and a Q1 gate, Q2 includes a Q2 source and a Q2 gate, and a bidirectional current limiter circuit further includes a first resistor R1 and a second resistor R2, and the Q1 source is connected in series with the Q2 source via R1 and R2, the Q1 gate is connected with the Q2 source and the Q2 gate is connected with the Q1 source, such that the Q1 source, R1, R2, and Q2 source are connected in series.

[0044]

[0051] Embodiment 6. The electrical energy storage system according to Embodiment 4 or 5, further comprising a reference bias circuit powered by an isolated power supply, wherein a bidirectional current limiter circuit is biased to a reference voltage via the reference bias circuit powered by an isolated power supply.

[0045]

[0052] Embodiment 7. The electrical energy storage system according to Embodiment 6, wherein the reference bias circuit includes two resistive voltage dividers Rt and Rb configured to adjust the reference voltage.

[0046]

[0053] Embodiment 8. An electrical energy storage system according to any one of Embodiments 5 to 7, wherein the sensing module is further configured to detect leakage between a plurality of electrochemical cells and a housing frame via a plurality of leakage voltage measurements performed in the states where S1 and S2 are open, S1 is closed and S2 is open, and S1 is open and S2 is closed.

[0047]

[0054] Embodiment 9. A method for detecting leakage in an electrical energy storage system, comprising: a sensing module coupled to the cathodes or anodes of a plurality of electrochemical cells; and a housing frame configured to house the plurality of electrochemical cells, wherein the sensing module includes a current limiter, a first relay switch S1, and a second relay switch S2, the current limiter being connected via S1 to the cathode of one or more of the plurality of electrochemical cells and via S2 to the anode of one or more of the plurality of electrochemical cells, each of the plurality of electrochemical cells being connected to one another in series, S1 being connected to a first electrochemical cell of the plurality of electrochemical cells, and S2 being connected to a second electrochemical cell of the plurality of electrochemical cells, the method comprising: sensing a leakage current between the housing frame and the plurality of electrochemical cells; comparing the leakage current with a threshold current value; and determining that there is leakage from the plurality of electrochemical cells to the housing frame if the leakage current exceeds the threshold current value.

[0048]

[0055] Embodiment 10. The method according to Embodiment 9, wherein the current limiter is a bidirectional current limiter circuit including a first depletion-layer metal oxide semiconductor field-effect transistor (MOSFET) Q1 and a second depletion-layer MOSFET Q2.

[0049]

[0056] Embodiment 11. A method according to Embodiment 10, wherein Q1 comprises a Q1 source and a Q1 gate, Q2 comprises a Q2 source and a Q2 gate, and the bidirectional current limiter circuit further comprises a first resistor R1 and a second resistor R2, and the Q1 source is connected in series with the Q2 source via R1 and R2, the Q1 gate is connected with the Q2 source, and the Q2 gate is connected with the Q1 source, so that the Q1 source, R1, R2, and Q2 source are connected in series.

[0050]

[0057] Embodiment 12. The method according to Embodiment 10 or 11, further comprising biasing a bidirectional current limiter circuit to a reference voltage via a reference bias circuit powered by an isolated power supply.

[0051]

[0058] Embodiment 13. The method according to Embodiment 12, wherein the reference bias circuit includes two resistive voltage dividers Rt and Rb configured to adjust the reference voltage.

[0052]

[0059] Embodiment 14. The method according to any one of Embodiments 9 to 13, wherein sensing leakage current between a plurality of electrochemical cells and a housing frame includes performing a plurality of leakage voltage measurements performed in the states S1 and S2 are open, S1 is closed and S2 is open, and S1 is open and S2 is closed.

[0053]

[0060] Embodiment 15. A module for detecting leaks in an electric vehicle battery, comprising a sensing circuit coupled to a plurality of electrochemical cells and a housing frame of an electric vehicle battery, configured to detect leaks between them, wherein the housing frame is configured to house the plurality of electrochemical cells therein, and the sensing circuit comprises a current limiter, a first relay switch S1, and a second relay switch S2, wherein the current limiter is electrically connected via S1 to the cathodes of one or more of the plurality of electrochemical cells and via S2 to the anodes of one or more of the plurality of electrochemical cells.

[0054]

[0061] Embodiment 16. A module according to Embodiment 15, wherein each of a plurality of electrochemical cells is connected to each other in series, S1 is connected to a first electrochemical cell among the plurality of electrochemical cells, and S2 is connected to a second electrochemical cell among the plurality of electrochemical cells.

[0055]

[0062] Embodiment 17. The module according to Embodiment 15 or 16, wherein the current limiter is a bidirectional current limiter circuit including a first depletion-layer metal oxide semiconductor field-effect transistor (MOSFET) Q1 and a second depletion-layer MOSFET Q2.

[0056]

[0063] Embodiment 18. A module according to Embodiment 17, wherein Q1 includes a Q1 source and a Q1 gate, Q2 includes a Q2 source and a Q2 gate, and a bidirectional current limiter circuit further includes a first resistor R1 and a second resistor R2, and the Q1 source is connected in series with the Q2 source via R1 and R2, the Q1 gate is connected with the Q2 source, and the Q2 gate is connected with the Q1 source, so that the Q1 source, R1, R2, and Q2 source are connected in series.

[0057]

[0064] Embodiment 19. The module according to Embodiment 17 or 18, further comprising a reference bias circuit powered by an isolated power supply, wherein a bidirectional current limiter circuit is biased to a reference voltage via the reference bias circuit powered by the isolated power supply, and the reference bias circuit comprises two resistive voltage dividers Rt and Rb configured to adjust the reference voltage.

[0058]

[0065] Embodiment 20. The module according to any one of embodiments 15 to 19, wherein the sensing circuit is further configured to detect leakage between a plurality of electrochemical cells and a housing frame via a plurality of leakage voltage measurements performed in the states where S1 and S2 are open, S1 is closed and S2 is open, and S1 is open and S2 is closed.

Claims

1. Multiple electrochemical cells, A housing frame configured to house the plurality of electrochemical cells inside, A sensing module including a current limiter and an ammeter, wherein the current limiter is electrically coupled to the cathode or anode of one or more of the plurality of electrochemical cells, and the housing frame and the ammeter are configured to measure the current between the current limiter and the plurality of electrochemical cells. A sensing module configured to detect leaks between the plurality of electrochemical cells and the housing frame, Electrical energy storage systems, including

2. The sensing module further includes a first relay switch S1 and a second relay switch S2, The current limiter is connected via S1 to one or more of the cathodes of the multiple electrochemical cells, The electrical energy storage system according to claim 1, wherein the current limiter is connected via S2 to one or more of the anodes of a plurality of electrochemical cells.

3. Each of the aforementioned electrochemical cells is connected to one another in a series arrangement. S1 is connected to the first electrochemical cell among the plurality of electrochemical cells, S2 is connected to the second electrochemical cell among the plurality of electrochemical cells. The electrical energy storage system according to claim 2.

4. The electrical energy storage system according to any one of claims 1 to 3, wherein the current limiter is a bidirectional current limiter circuit including a first depletion-layer metal oxide semiconductor field-effect transistor (MOSFET) Q1 and a second depletion-layer MOSFET Q2.

5. Q1 includes the Q1 source and the Q1 gate, Q2 includes the Q2 source and the Q2 gate, The bidirectional current limiter circuit further includes a first resistor R1 and a second resistor R2, Source Q1 is connected in series to Source Q2 via R1 and R2, such that Source Q1, R1, R2, and Source Q2 are connected in series. The Q1 gate is connected to the Q2 source, The Q2 gate is connected to the Q1 source. The electrical energy storage system according to claim 4.

6. The bidirectional current limiter circuit further includes a reference bias circuit powered by an isolated power supply, wherein the bidirectional current limiter circuit is biased to a reference voltage via the reference bias circuit powered by the isolated power supply. The electrical energy storage system according to claim 4 or 5.

7. The electrical energy storage system according to claim 6, wherein the reference bias circuit includes two resistive voltage dividers Rt and Rb configured to adjust the reference voltage.

8. The electrical energy storage system according to any one of claims 5 to 7, wherein the sensing module is further configured to detect the leakage between the plurality of electrochemical cells and the housing frame via a plurality of leakage voltage measurements performed in the states where S1 and S2 are open, S1 is closed and S2 is open, and S1 is open and S2 is closed.

9. A method for detecting leaks in an electrical energy storage system, The provision includes a sensing module coupled to the cathode or anode of a plurality of electrochemical cells, and a housing frame configured to accommodate the plurality of electrochemical cells, The sensing module includes a current limiter, a first relay switch S1, and a second relay switch S2, wherein the current limiter is connected via S1 to one or more of the cathodes of a plurality of electrochemical cells, and via S2 to one or more of the anodes of a plurality of electrochemical cells, and each of the plurality of electrochemical cells is connected to each other in series, with S1 connected to a first electrochemical cell of the plurality of electrochemical cells, and S2 connected to a second electrochemical cell of the plurality of electrochemical cells. The method described above is To sense the leakage current between the housing frame and the plurality of electrochemical cells, The leakage current is compared with the threshold current value, When the leakage current exceeds the threshold current value, it is determined that there is leakage from the plurality of electrochemical cells to the housing frame. A method that includes this.

10. The method according to claim 9, wherein the current limiter is a bidirectional current limiter circuit including a first depletion-layer metal oxide semiconductor field-effect transistor (MOSFET) Q1 and a second depletion-layer MOSFET Q2.

11. Q1 includes the Q1 source and the Q1 gate, Q2 includes the Q2 source and the Q2 gate, The bidirectional current limiter circuit further includes a first resistor R1 and a second resistor R2, Source Q1 is connected in series to Source Q2 via R1 and R2, such that Source Q1, R1, R2, and Source Q2 are connected in series. The Q1 gate is connected to the Q2 source, The Q2 gate is connected to the Q1 source. The method according to claim 10.

12. The further includes biasing the bidirectional current limiter circuit to a reference voltage via a reference bias circuit powered by an isolated power supply, The method according to claim 10 or 11.

13. The method according to claim 12, wherein the reference bias circuit includes two resistive voltage dividers Rt and Rb configured to adjust the reference voltage.

14. The method according to any one of claims 9 to 13, wherein sensing the leakage current between the plurality of electrochemical cells and the housing frame includes performing a plurality of leakage voltage measurements performed in the open state of S1 and S2, the closed state of S1 and S2 open, and the open state of S1 and S2 closed.

15. A module for detecting leaks in electric vehicle batteries, The sensing circuit is coupled to a plurality of electrochemical cells and the housing frame of the electric vehicle battery and is configured to detect leaks between them, wherein the housing frame is configured to house the plurality of electrochemical cells inside it, and the sensing circuit includes a current limiter, a first relay switch S1, and a second relay switch S2. A module in which the current limiter is electrically connected via S1 to one or more cathodes of a plurality of electrochemical cells, and via S2 to one or more anodes of a plurality of electrochemical cells.

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