DIAGNOSIS AND REDUCTION OF BATTERY IMBALISMS

Abstract

Techniques for diagnosing and mitigating battery imbalances are provided. In one embodiment, the techniques include isolating a first battery cell from a plurality of battery cells via a first isolation unit, determining the state of health of the first battery cell via a complex impedance measurement unit, and controlling the first battery cell via a controller based on the state of health of the first battery cell.

Description

INTRODUCTION

[0001] The present disclosure relates to battery cells, in particular to the use of impedance estimation to detect deterioration of individual battery cells in a battery pack or group of cells that are out of balance.

[0002] Traditional battery packs often contain individual battery cells that degrade at different rates. The battery pack can still power a load even with the deterioration of some individual cells. However, using a battery pack containing degraded cells can reduce performance and reliability and lead to damage to the battery pack itself. SUMMARY

[0003] In an exemplary embodiment, a method is provided for diagnosing and mitigating battery imbalances. The method comprises isolating a first battery cell from a plurality of battery cells via a first isolation unit, determining the state of health of the first battery cell via a complex impedance measurement unit, and controlling the first battery cell via a controller based on the state of health of the first battery cell.

[0004] In addition to one or more of the features described herein, the first insulating unit comprises a first terminal point connected to a first end of a switch and a second terminal point connected to a second end of the switch.

[0005] In addition to one or more of the features described herein, the method also includes isolating a second battery cell from the plurality of battery cells via a second isolation unit, determining a state of health of the second battery cell via the complex impedance measurement unit, and determining, via control, that a difference between the state of health of the first battery cell and the state of health of the second battery cell exceeds a state of health threshold, wherein the difference indicates that a remaining service life of the first battery cell is less than a remaining service life of the second battery cell, and controlling the first battery cell by isolating the first battery cell from the plurality of battery cells via the first isolation unit.

[0006] In addition to one or more of the features described herein, the first insulating unit comprises a first terminal point connected to a first end of the switch, wherein a second end of the switch is connected to a first electrical path and a third end of the switch is connected to a second electrical path, and a second terminal point connected to the first electrical path and the second electrical path, wherein the second electrical path comprises a resistor or an RC filter.

[0007] In addition to one or more of the features described herein, the method also includes determining a target frequency range of a frequency response via the controller, determining the frequency response over the target frequency range via the complex impedance measurement unit, determining a state of health of the first battery cell based on the frequency response via the controller, and determining, via the controller, that a difference between the state of health of the first battery cell and a state of health estimation map exceeds a battery imbalance threshold, with the first battery cell being controlled based on the state of health of the first battery cell.

[0008] In addition to one or more of the features described herein, the complex impedance measurement unit is a device designed to apply an AC input signal to the first battery cell, to measure an AC output signal of the first battery cell, and to determine real and imaginary impedance values ​​based on the AC input signal and the AC output signal.

[0009] In addition to one or more of the features described herein, the state of health of the first battery cell is a map or profile representing a remaining service life of the first battery cell relative to at least one metric, wherein the remaining service life of the first battery cell includes at least one internal impedance value, number of expected remaining life cycles or percentage of remaining charge, and the at least one metric includes time, cycle count, temperature range, voltage or current usage or capacity range of the first battery cell.

[0010] In another exemplary embodiment, a vehicle performance control system is provided to diagnose and mitigate battery imbalances. The system comprises a plurality of battery cells, a first isolation unit, a complex impedance measurement unit, a processor, and memory or storage containing an algorithm or computer instructions which, when executed by the processor, perform an operation that includes isolating a first battery cell from the plurality of battery cells via the first isolation unit, determining a state of health of the first battery cell via the complex impedance measurement unit, and controlling the first battery cell based on the state of health of the first battery cell via the processor.

[0011] In addition to one or more of the features described herein, the first insulating unit comprises a first terminal point connected to a first end of a switch and a second terminal point connected to a second end of the switch.

[0012] In addition to one or more of the features described herein, the process also includes isolating a second battery cell from the plurality of battery cells via a second isolation unit, determining a state of health of the second battery cell via the complex impedance measurement unit, and determining, via control, that a difference between the state of health of the first battery cell and the state of health of the second battery cell exceeds a state of health threshold, the difference indicating that a remaining service life of the first battery cell is less than a remaining service life of the second battery cell, and controlling the first battery cell by isolating the first battery cell from the plurality of battery cells via the first isolation unit.

[0013] In addition to one or more of the features described herein, the first insulating unit comprises a first terminal point connected to a first end of the switch, wherein a second end of the switch is connected to a first electrical path and a third end of the switch is connected to a second electrical path, and a second terminal point connected to the first electrical path and the second electrical path, wherein the second electrical path comprises a resistor or an RC filter.

[0014] In addition to one or more of the features described herein, the process also includes determining a target frequency range of a frequency response via the controller, determining the frequency response over the target frequency range via the complex impedance measurement unit, determining a state of health of the first battery cell based on the frequency response via the controller, and determining, via the controller, that a difference between the state of health of the first battery cell and a state of health estimation map exceeds a battery imbalance threshold, with the first battery cell being controlled based on the state of health of the first battery cell.

[0015] In addition to one or more of the features described herein, the complex impedance measurement unit is a device designed to apply an AC input signal to the first battery cell, to measure an AC output signal of the first battery cell, and to determine real and imaginary impedance values ​​based on the AC input signal and the AC output signal.

[0016] In addition to one or more of the features described herein, the state of health of the first battery cell is a map or profile representing a remaining service life of the first battery cell relative to at least one metric, wherein the remaining service life of the first battery cell includes at least one internal impedance value, number of expected remaining life cycles or percentage of remaining charge, and the at least one metric includes time, cycle count, temperature range, voltage or current usage or capacity range of the first battery cell.

[0017] In yet another exemplary embodiment, a computer-readable storage medium containing computer-readable program code is provided for diagnosing and mitigating battery imbalances. The computer-readable program code, which can be executed by one or more computer processors to perform an operation, comprises isolating a first battery cell from a plurality of battery cells via a first isolation unit, determining the state of health of the first battery cell via a complex impedance measurement unit, and controlling the first battery cell via a control unit based on the state of health of the first battery cell.

[0018] In addition to one or more of the features described herein, the first insulating unit comprises a first terminal point connected to a first end of a switch and a second terminal point connected to a second end of the switch.

[0019] In addition to one or more of the features described herein, the process also includes isolating a second battery cell from the plurality of battery cells via a second isolation unit, determining a state of health of the second battery cell via the complex impedance measurement unit, and determining, via control, that a difference between the state of health of the first battery cell and the state of health of the second battery cell exceeds a state of health threshold, the difference indicating that a remaining service life of the first battery cell is less than a remaining service life of the second battery cell, and controlling the first battery cell by isolating the first battery cell from the plurality of battery cells via the first isolation unit.

[0020] In addition to one or more of the features described herein, the first insulating unit comprises a first terminal point connected to a first end of the switch, wherein a second end of the switch is connected to a first electrical path and a third end of the switch is connected to a second electrical path, and a second terminal point connected to the first electrical path and the second electrical path, wherein the second electrical path comprises a resistor or an RC filter.

[0021] In addition to one or more of the features described herein, the process also includes determining a target frequency range of a frequency response via the controller, determining the frequency response over the target frequency range via the complex impedance measurement unit, determining a state of health of the first battery cell based on the frequency response via the controller, and determining, via the controller, that a difference between the state of health of the first battery cell and a state of health estimation map exceeds a battery imbalance threshold, with the first battery cell being controlled based on the state of health of the first battery cell.

[0022] In addition to one or more of the features described herein, the state of health of the first battery cell is a map or profile representing a remaining service life of the first battery cell relative to at least one metric, wherein the remaining service life of the first battery cell includes at least one internal impedance value, number of expected remaining life cycles or percentage of remaining charge, and the at least one metric includes time, cycle count, temperature range, voltage or current usage or capacity range of the first battery cell.

[0023] The aforementioned features and advantages, as well as other features and advantages of the disclosure, are readily apparent from the following detailed description in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Further features, advantages and details are listed only as examples in the following detailed description, which refers to the drawings in which: Fig. 1 illustrates a battery control environment according to one embodiment; Fig. 2 illustrates a computing environment according to one embodiment; Fig. 3A-3C Insulation units according to one or more embodiments are illustrated; Fig. 4. A flowchart of a method for diagnosing and reducing battery imbalances according to one embodiment is illustrated; Fig. 5. A flowchart of a method for diagnosing and reducing battery imbalances according to another embodiment is illustrated; and Fig. Figure 6 illustrates a flowchart of a method for diagnosing and reducing battery imbalances according to a further embodiment. DETAILED DESCRIPTION

[0025] The following description is merely exemplary and is not intended to limit the present disclosure, its application, or its use. It is understood that in the drawings, corresponding reference numerals denote identical or corresponding parts and features. As used herein, the term "unit" refers to a circuit that may include an application-specific integrated circuit (ASIC), an electronic circuit, a processor (common, dedicated, or group), memory executing one or more software or firmware programs, a combinational logic circuit, and / or other suitable components providing the described functionality.

[0026] Embodiments of the present disclosure improve battery cell diagnostic and mitigation systems by providing a battery imbalance mitigation module designed to isolate, diagnose, and control cells in a battery pack or cell group (e.g., individual battery cells connected in series or parallel). The battery imbalance mitigation module can isolate each cell of the battery pack or cell group by means of an isolation unit assigned to that cell. Furthermore, the battery imbalance mitigation module can diagnose each cell to a complex impedance measurement unit based on the frequency response of that cell. The battery imbalance mitigation module can also control the isolation units to mitigate the effects of using a battery pack or cell group that includes a cell with a battery imbalance (e.g.,age-related deterioration of the cell) can be reduced.

[0027] An advantage of the disclosed embodiments is that performance problems when using battery packs or cell groups containing degraded cells are reduced by controlling or disabling the use of the degraded cells. Furthermore, the embodiments of the present disclosure can improve the performance, reliability, and longevity of the battery packs or cell groups by correcting imbalances in the cells of the battery packs or cell groups.

[0028] Fig. Figure 1 illustrates a battery control environment 100 according to one embodiment. In the illustrated embodiment, the battery control environment 100 comprises a circuit configuration 102 (the isolation units 104). 1-N , cells 106 1-N and a power source 110) and a control unit 101.

[0029] In one embodiment, the insulating units 104 1-N Circuit configurations used to connect and disconnect cells 106 1-N They can be operated with circuit configuration 102. Each of the isolation units 104 1-N can include at least two input or output connection points with circuit configuration 102. The isolation units 104 1-N Connection points can also include control 101 and ground 103.

[0030] In the illustrated embodiment, each of the cells comprises 106 1-N An anode (e.g., anode 105) is connected to ground 103, and a cathode (e.g., cathode 107) is connected to a first terminal (e.g., terminal 109) of a corresponding insulating unit. The power source 110 is connected to ground 103 and to a second terminal (e.g., terminal 111) of each of the insulating units 104. 1-Nconnected and connected to control unit 101.

[0031] In one embodiment, the control unit 101 is designed to control circuit elements of the insulating units 104. 1-N to operate the cells 106 1-N to isolate and diagnose. Control unit 101 will continue in Fig. 2 explained.

[0032] The control unit 101 can be based on the circuit configurations of the isolation units 104. 1-N Selecting isolation and diagnostic techniques. Examples of circuit configurations for isolation units 104 1-N will be in the Fig. 3A-3C are explained in detail. The isolation and diagnostic techniques are described in the Fig. 4-6 described.

[0033] Fig. Figure 2 illustrates a computing environment 200 according to one embodiment. In the illustrated embodiment, the computing environment 200 comprises a controller 101, a network 230, and isolation units 104. 1-N, a power source 110 and a unit 240 for measuring the complex impedance. In one embodiment, the controller 101 is a battery management system of a vehicle, and the circuit configuration 102 represents a battery pack of the vehicle.

[0034] In one embodiment, the controller 101 comprises a processor 204, which receives instructions and data via a bus 220 from a memory or storage device 206. Not all components of the controller 101 are shown. The controller 101 is generally under the control of an operating system (OS) capable of performing or supporting the functions or processes disclosed herein. The processor 204 is a programmable logic device that performs instruction, logic, and mathematical processing and may represent one or more CPUs. The processor may execute one or more algorithms, instruction sets, or applications in the memory or storage device 206 to perform the functions or processes described herein.

[0035] Storage or repository 206 can represent hard disk drives, solid-state drives, flash memory devices, optical media, and the like. Storage or repository 206 can also include structured storage (e.g., a database). Furthermore, storage or repository 206 can also include storage that is physically located elsewhere. For example, storage or repository 206 may be physically located on another computer that is communicatively coupled to the controller 101 via bus 220 or network 230.

[0036] The controller 101 can be connected to other computers (e.g., controllers, distributed databases, servers, or web hosts) and the isolation units 104 via a network interface 210 and / or the network 230. 1-NThe network 230 may be connected to the power source 110 or the complex impedance measurement unit 240. For example, the network 230 may comprise a local area network, a wide area network, or a wireless network. In one embodiment, the network includes a CAN (Controller Area Network) or TCP (Transmission Control Protocol) bus. The network 230 may also include any combination of buses, physical transmission cables, optical transmission fibers, wireless transmission, routers, firewalls, switches, gateway computers, or edge servers. The network interface 210 may be any type of network communication device that enables the controller 101 to communicate with computers and other components of the computing environment 200 via the network 230.

[0037] In the illustrated embodiment, the memory or storage 206 comprises a module 208 for reducing battery imbalance (BIM module). In one embodiment, the BIM module 208 represents one or more algorithms, instruction sets, software applications, or other computer-readable program code that can be executed by the processor 204 to perform the functions, operations, or processes described herein.

[0038] The BIM module 208 can handle the insulation units 104 1-N control to control cells 106 1-Nto connect to and disconnect from the circuit configuration 102. In one embodiment, the BIM module 208 disconnects all but one cell (an “isolated” cell) from the circuit configuration 102. Subsequently, the BIM module 208 can control the complex impedance measurement unit 240 to determine a frequency response of the isolated cell. The BIM module 208 can use the frequency response to determine a state of health (SOH) of the isolated cell and, based on the SOH, can control the use of the isolated cell. This process is described herein in the Fig. 4-6 explained in more detail.

[0039] The unit 240 for measuring complex impedance can be an electrochemical impedance spectroscopy device, a potentiostat, or another device used to apply alternating current input signals to the cells 106. 1-N , for measuring the AC output signals of cells 106 1-Nand is designed to determine real and imaginary impedance values ​​based on AC input and AC output signals. For example, the AC input signals can be voltage signals, and the AC output signals can be current signals. Therefore, the Unit 240 can divide the voltage signals by the current signals to obtain impedance representations of the cells 106 for measuring complex impedance. 1-N to determine.

[0040] In one embodiment, the impedance representations are modeled as Bode plots or Nyquist plots. In one embodiment, the unit 240 for measuring the complex impedance modulates an AC signal from the power source 110 to provide the AC input signal to the isolation units 104. 1-N to create, which then goes to cells 106 1-N is created.

[0041] Fig. Figures 3A-3C illustrate insulating units according to one or more embodiments. In each of the embodiments shown in Fig. In embodiments 3A-3C illustrated, the insulating unit 1041 represents a circuit configuration that is common to all insulating units 104. 1-N common to the embodiment.

[0042] At the in Fig. In the embodiment illustrated in Figure 3A, the insulating unit 1041 comprises a switch 302A, which is connected to a cell 1061 via a first connection point 320A of the insulating unit 1041. The switch 302A is also connected to the power source 110 via a second connection point 322A of the insulating unit 1041.

[0043] The controller 101 can actuate the switch 302A to connect or disconnect the cell 1061 from the circuit configuration 102. In one embodiment, the controller 101 actuates the switch in the insulating units 104. 1-N , to create a SOH for each of the cells 106 1-Nto isolate and determine. This process is described in detail herein in Fig. 5 explained.

[0044] At the in Fig. In the embodiment illustrated in Figure 3B, the isolation unit 1041 comprises a switch 302B, which is connected to a cell 1061 via a first terminal 320B of the isolation unit 1041. The switch 302B is also connected to the power source 110 via a top electrical path 310B, which is connected to a second terminal 322B of the isolation unit 1041. The switch 302B is also connected to a resistor 304B and the power source 110 via a bottom electrical path 312B, which is connected to the second terminal 322B of the isolation unit 1041. The isolation unit 1041 may also include an optional additional switch (not shown) connected to the second terminal 322B to connect or disconnect the isolation unit 1041 from the circuit configuration 102.

[0045] The controller 101 can actuate the switch 302B to connect the cell 1061 directly to the power source 110 via the uppermost electrical path 310B, or to connect the cell 1061 to the resistor 304B and the power source 110 via the lowermost electrical path 312B. In one embodiment, the resistor 304B presents an impedance signature of the insulating unit 1041 with respect to the cell 1061. Each of the insulating units 104 1-N can have a different impedance signature. In one embodiment, the resistor 304B is a variable resistor that can be electromechanically adjusted by the controller 101 to apply a different impedance signature to the cell 1061. This can be done for each of the insulating units 104 1-N to be carried out to determine 106 cells for each of the cells 1-N to provide a different impedance signature. Diagnostic techniques for such isolation units 104 1-N will be further discussed here Fig. 6 explained.

[0046] At the in Fig. In the embodiment illustrated in Figure 3B, the insulating unit 1041 comprises a switch 302C, which is connected to a cell 1061 via a first terminal 320C of the insulating unit 1041. The switch 302C is also connected to the power source 110 via a top electrical path 310C, which is connected to a second terminal 322C of the insulating unit 1041. The switch 302C is also connected to an RC filter (comprising the resistor 304C and the capacitor 306C) and the power source 110 via a bottom electrical path 312C, which is connected to the second terminal 322C of the insulating unit 1041. A first end of the capacitor 306C is connected to the lowest electrical path 312C between the switch 302C and the resistor 304C, and a second end of the capacitor 306C is connected to ground 103 via a third terminal 342C of the insulating unit 1041.

[0047] The controller 101 can actuate the switch 302C to connect cell 1061 directly to the power source 110 via the uppermost electrical path 310C, or to connect cell 1061 to the RC filter and the power source 110 via the lowermost electrical path 312C. In one embodiment, the resistor 304C represents an impedance signature of the isolation unit 1041 with respect to cell 1061. Each of the isolation units 104 1-N can have a different impedance signature. In one embodiment, the resistor 304C is a variable resistor that can be electromechanically adjusted by the controller 101 to apply a different impedance signature to the cell 1061. This can be done for each of the insulating units 104 1-N to be carried out to determine 106 cells for each of the cells 1-N to provide a different impedance signature. Diagnostic techniques for such isolation units 104 1-N will be further discussed here Fig. 6 explained.

[0048] Fig. Figure 4 illustrates a flowchart of a method 400 for diagnosing and mitigating battery imbalances according to one embodiment. In one embodiment, the method 400 is performed when the cells are not in a state of high energy depletion. If the cells 106 1-N For example, if used in a vehicle, the procedure can be carried out when the vehicle is not in motion.

[0049] The process begins at block 402. At block 404, the BIM module 208 selects a diagnostic technique based on a circuit configuration of an isolation unit. In one embodiment, when the isolation units 104 1-N the in Fig. 3A illustrates the circuit configuration; the BIM module 208 introduces the following: Fig. The 5 described procedures are used. If the insulating units are 104 1-N the in Fig. To reproduce the circuit configurations illustrated in 3B-3C, the BIM module 208 introduces the [unclear] in Fig. 6 described procedures.

[0050] Blocks 406-412 describe general processes of the present revelation, which are found in the Fig. 5 and Fig. 6 will be explained in more detail. In block 406, the BIM module 208 isolates a cell via the isolation unit. As explained above, in one embodiment, a cell (e.g., cell 1061) is considered isolated when an isolation unit corresponding to the cell is used to connect the cell to the circuit configuration 102 (or to maintain a connection of the cell), while other cells (e.g., 106) 2-N) are disconnected from circuit configuration 102. In one embodiment, some or all other cells are disconnected from the circuit configuration. In another embodiment, groups of cells can be isolated and used according to method 400 to increase the efficiency of diagnosing and reducing battery imbalance.

[0051] In block 408, the BIM module 208 determines the state of health (SOH) of the battery cell via a complex impedance measurement unit 240. The BIM module 208 can identify a SOH based on the cell's frequency response. In one embodiment, the frequency response of a cell represents an impedance profile of the cell, encompassing real and imaginary impedance values ​​over a frequency range. The BIM module 208 can generate the frequency response by controlling the complex impedance measurement unit 240 to apply an AC input signal to the cell, measure the cell's AC output signals, and determine real and imaginary impedance values ​​based on the AC input and output signals.

[0052] In one embodiment, the state of health (SOH) of a battery cell represents the remaining service life of the cell as the ratio between the current state of the cell and the ideal state of the cell. The SOH can be displayed as a map or profile showing the remaining service life of the cell (e.g., an internal impedance value, a number of expected remaining service cycles, a percentage of remaining charge, or the like) relative to at least one metric (e.g., time, number of cycles, temperature range, voltage or current consumption, cell capacity range, or the like). The BIM module 208 can determine the SOH value of a cell based on the cell's impedance (from the frequency response), capacity, and voltage output.

[0053] In block 410, the BIM module 208 controls the battery cell via a controller 101 based on its state of health. In an embodiment where the cell is determined to have a battery imbalance, the BIM module 208 uses an isolation unit to disconnect the cell from the circuit configuration 102, allowing the battery pack or cell group to deliver power without the contribution of the disconnected cell. A battery imbalance can represent an increased impedance or energy depletion of one cell in the circuit configuration 102 relative to at least one other cell in the circuit configuration 102.

[0054] The BIM module 208 can also determine the state of health (SOH) of the other cells in the circuit configuration 102 over time. In one embodiment, after determining that a difference between an SOH value of the disconnected cell and an SOH value of one or more of the other cells (or an average of the states of health of the other cells) exceeds a threshold, the BIM module 208 can use the isolation unit to reconnect the disconnected cell to the circuit configuration 102. In this way, the BIM module 208 can control the energy imbalance of the cells and mitigate the risks associated with using a battery pack or cell group that includes a cell in an imbalance. Method 400 terminates at block 412.

[0055] Fig. Figure 5 illustrates a flowchart of a method 500 for diagnosing and mitigating battery imbalances according to another embodiment. Method 500 shows an example of diagnosing and mitigating a battery imbalance when the insulating units 104 1-N represent a circuit configuration that is in Fig. 3A is shown. Procedure 500 begins at block 502.

[0056] In block 504, the BIM module 208 isolates a first battery cell from a plurality of battery cells. The BIM module 208 can control a switch of an isolation unit (e.g., switch 302A) to connect or disconnect a cell from the circuit configuration 102. As described herein, in one embodiment, the first battery cell is considered isolated when the first battery cell (e.g., cell 1061) is connected to (or maintains a connection with) the circuit configuration 102, and other cells (e.g., cells 106) are not.2-N ) are separated from circuit configuration 102.

[0057] In block 506, the BIM module 208 determines the state of health (SOH) of the first battery cell. As described here, the BIM module 208 can control the complex impedance measurement unit 240 to generate a frequency response of the first battery cell. The BIM module 208 can then determine the SOH value based on the capacity, voltage, and frequency response of the first battery cell. In one embodiment, the SOH of the first battery represents a remaining service life (e.g., an internal impedance value, a number of expected remaining service cycles, a percentage of remaining charge, or the like) of the first battery cell.

[0058] In block 508, the BIM module 208 isolates a second battery cell from the multitude of battery cells. In block 510, the BIM module 208 determines a state of health (SOH) for the second battery cell. The procedure 500 can perform these processes in a similar manner to the processes performed in blocks 504 and 506.

[0059] In block 512, BIM module 208 determines whether a difference between the state of health (SOH) of the first battery cell and the state of health of the second battery cell exceeds a state of health threshold. After BIM module 208 determines that the SOH threshold has not been exceeded, it determines that the first and second battery cells are not out of balance. Therefore, procedure 500 proceeds to block 504, where it proceeds as described above. However, if it is determined that the SOH threshold has been exceeded, BIM module 208 determines that an imbalance exists between the first and second battery cells. Procedure 500 then proceeds to block 514.

[0060] At block 514, the BIM module 208 controls the first or second battery cell. In one embodiment, the BIM module 208 uses an isolation unit to disconnect the first or second battery cell from the circuit configuration 102 based on the SOH values ​​corresponding to the cells (e.g., the BIM module 208 can disconnect the cell with a shorter remaining service life). Method 500 terminates at block 516.

[0061] Fig. Figure 6 illustrates a flowchart of a method 600 for diagnosing and mitigating battery imbalances according to yet another embodiment. Method 600 shows an example of diagnosing and mitigating a battery imbalance when the insulating units 104 1-N represent a circuit configuration that is in Fig. 3B-3C is shown. Procedure 600 begins at block 602.

[0062] In block 604, the BIM module 208 isolates one battery cell from a multitude of battery cells. If the circuit configuration of the isolation units 104 1-N the in Fig. As illustrated in the circuit configuration shown in Figure 3B, the BIM module 208 can control a switch (e.g., switch 302B) of an isolation unit (e.g., isolation unit 1041) to connect a cell (e.g., cell 1061) directly to the power source 110 via a first electrical path of the isolation unit 1041. The BIM module 208 can also control the switch 302B to connect to the power source 110 via a resistor 304B in a second electrical path of the isolation unit 1041.

[0063] In one embodiment, cell 1061 is considered isolated when it is connected to the power source 110 via the first electrical path, while other cells (e.g., cells 106) are not. 2-N) via the second electrical path of corresponding insulating units (e.g. insulating units 104) 2-N ) are connected to the power source 110. In this way, the BIM module 208 can determine the frequency response of the isolated cell based on an original impedance profile of the circuit configuration of the isolation units 104. 1-N evaluate.

[0064] In another embodiment, cell 1061 is considered isolated when it is connected to the power source 110 via the second electrical path. Due to the isolation of cells 106 1-N The circuit components of the insulating units 104 can be connected via the second electrical path. 1-N as impedance signatures compared to cells 106 1-N In one embodiment, the BIM module 208 can be used to determine the impedance signatures of the insulation units 104. 1-Nchange. For example, the BIM module 208 can make different electromechanical adjustments to the variable resistances of the different insulation units. Therefore, the impedance signatures can be used to determine the frequency response of each of the cells 106. 1-N to isolate by shifting an impedance signature opposite one cell into a different impedance range that does not overlap with the impedance signature of another cell.

[0065] If the circuit configuration of the isolation units 104 1-N the in Fig. As illustrated in the circuit configuration shown in Figure 3C, the BIM module 208 can control switches of an isolation unit (e.g., switches 302C and 308C) to connect or disconnect a cell (e.g., cell 1061) from the circuit configuration 102. When connecting cell 1061 to the circuit configuration 102, the BIM module 208 can connect a cell directly to the power source 110 via a first electrical path of the isolation unit 1041. The BIM module 208 can also control switch 302C to connect to the power source 110 via an RC filter (comprising a resistor 304C and a capacitor 306C) in a second electrical path of the isolation unit 1041.

[0066] In one embodiment, cell 1061 is considered isolated when it is connected to the power source 110 via the first electrical path, while other cells (e.g., cells 106) are not. 2-N) via the second electrical path of corresponding insulating units (e.g. insulating units 104) 2-N ) are connected to the power source 110. In this way, the impedance response of a cell isolated via the first electrical path can be easily distinguished from the impedance response of a cell connected to the second electrical path (whose signal is filtered out by the RC filters in a common frequency range).

[0067] In block 606, the BIM module 208 defines a target frequency range for a frequency response. In one embodiment, the target frequency range represents a minimum frequency range that covers an expected impedance range of the battery cell and an insulation unit corresponding to the battery cell. For insulation units 104 1-N , which the in Fig. As illustrated in section 3B, the target frequency range can be determined based on the impedance of a battery cell and the impedance signature of the isolation unit relative to the battery cell. For isolation units 104 1-N , which are in Fig. As illustrated in the circuit configurations shown in 3C, the target frequency range can be determined based on the impedance of the isolated battery cell.

[0068] In block 608, the BIM module 208 determines the frequency response over the target frequency range. In one embodiment, the frequency response of a cell represents an impedance profile of the cell, encompassing real and imaginary impedance values ​​over a target frequency range. The BIM module 208 can generate the frequency response by controlling the complex impedance measurement unit 240 to apply an AC input signal to the cell, measure the cells' AC output signals, and determine real and imaginary impedance values ​​based on the AC input and output signals.

[0069] During this process, the BIM module 208 can also perform a circuit pattern test to determine if there is a fault in the circuit mechanisms of the insulating units 140. 1-N is present. For example, the BIM module 208 can specify predetermined impedances of the insulation units 104. 1-Nuse to determine an expected impedance range of the insulating units 104 1-N to generate. If the measured impedances of the insulating units are 140 1-N If the impedances are outside the expected range, the BIM module 208 can determine that the measured impedances reflect a fault in the switching mechanisms, which may be due to an unintended aggregation or removal from the circuit configuration 102 of isolation units 104. 1-N , whose impedances were measured, may have caused.

[0070] In Block 610, the BIM module 208 determines the state of health (SOH) of the battery cell based on its frequency response. In one embodiment, the SOH of a battery cell represents the remaining service life of the cell as the ratio between its current state and its ideal state. The SOH can be displayed as a map or profile showing the current remaining service life (e.g., an internal impedance value, the number of expected remaining service cycles, a percentage of remaining charge, and the like) of the cell relative to at least one metric (e.g., time, cycle count, temperature range, voltage or current consumption, cell capacity range, and the like). The BIM module 208 can determine the SOH value of a cell based on its impedance (from the frequency response), capacity, and voltage output.

[0071] In block 612, BIM module 208 determines whether a difference between the battery cell's state of health (SOH) and a state of health estimation map exceeds a battery imbalance threshold. In one embodiment, the SOH estimation map represents the expected remaining service life of the cell at the start of its use in circuit configuration 102. In another embodiment, the SOH map represents an expected lifetime profile of a cell generated during cell manufacturing.

[0072] After BIM module 208 determines that the difference does not exceed the battery imbalance threshold, it determines that the remaining cell lifespan does not deviate from expectations and that there is no imbalance (e.g., increased internal impedance) in the battery cell. Therefore, procedure 600 proceeds to block 604, where it proceeds as described above. However, if it is determined that the difference exceeds the battery imbalance threshold, BIM module 208 determines that the remaining cell lifespan deviates from expectations and that there is an imbalance in the battery cell. Procedure 600 then proceeds to block 614.

[0073] In block 614, the BIM module 208 controls the battery cell based on the battery cell's state of health. In one embodiment, if the cell exhibits an imbalance, the BIM module 208 uses an isolation unit to disconnect the cell from the circuit configuration 102, allowing the battery pack or cell group to deliver power without the contribution of the disconnected cell.

[0074] The BIM module 208 can also determine the state of health (SOH) of the other cells in the circuit configuration 102 over time. In one embodiment, after determining that a difference between the SOH of the disconnected cell and the SOH of one or more of the other cells (or an average of the health states of the other cells) exceeds a threshold, the BIM module 208 can use an isolation unit to reconnect the disconnected cell to the circuit configuration 102. In this way, the BIM module 208 can control the energy imbalance of the cells and mitigate the risks associated with using a battery pack or cell group that includes a cell in imbalance. Method 600 terminates at block 616.

[0075] The terms "a" and "an" do not denote a quantity limitation, but rather indicate the presence of at least one of the mentioned items. The term "or" means "and / or" unless the context clearly indicates otherwise. Whenever the patent specification refers to "an aspect," this means that a specific element (e.g., a feature, a structure, a step, or a property) described in connection with that aspect is included in at least one of the aspects described therein and may or may not be present in other aspects. Furthermore, it is understood that the described elements in the various aspects may be combined in any suitable manner.

[0076] When an element, such as a layer, film, area, or substrate, is described as being "on" another element, it may be located directly on top of the other element, or there may be elements in between. Conversely, when an element is described as being "directly on" another element, there are no elements in between.

[0077] Unless otherwise stated herein, all testing standards are the latest standard in force on the filing date of this application or, if priority is claimed, the filing date of the earliest priority application in which the testing standard appears.

[0078] Unless otherwise defined, the technical and scientific terms used herein have the same meaning as they are generally understood by a person skilled in the field to which this disclosure belongs.

[0079] While the above disclosure has been described with reference to exemplary embodiments, it is known to those skilled in the art that various modifications can be made and equivalent elements substituted without altering its scope. Furthermore, many modifications can be made to adapt a particular situation or material to the teachings of the disclosure without deviating from its essential scope. Therefore, the present disclosure is not intended to be limited to the specific embodiments disclosed, but rather to encompass all embodiments that fall within its scope.

Claims

[1] Vehicle power control system comprising: a first battery cell; a variety of battery cells; a first isolation unit; a unit for measuring complex impedance; a processor; and a memory or storage comprising an algorithm or computer instructions which, when executed by the processor, performs an operation comprising: Isolating, via the first insulation unit, the first battery cell from the plurality of battery cells; Determining, via the complex impedance measurement unit, a state of health of the first battery cell; and Control, via the processor, the first battery cell based on the state of health of the battery cell. [2] The vehicle power control system according to claim 1, wherein the first isolation unit comprises: a first connection point connected to a first end of a switch; and a second connection point connected to a second end of the switch. [3] The vehicle power control system of claim 2, wherein the process further comprises: Isolating, via a second insulation unit, a second battery cell from the plurality of battery cells; Determining, via the complex impedance measurement unit, a state of health of the second battery cell; and Determining, via the processor, that a difference between the state of health of the first battery cell and the state of health of the second battery cell exceeds a state of health threshold, wherein the difference indicates that a remaining useful life of the first battery cell is less than a remaining useful life of the second battery cell, and wherein the first battery cell is controlled by isolating the first battery cell from the plurality of battery cells via the first isolation unit. [4] The vehicle power control system according to claim 1, wherein the first isolation unit comprises: a first terminal connected to a first end of the switch, a second end of the switch connected to a first electrical path, and a third end of the switch connected to a second electrical path; and a second connection point connected to the first electrical path and the second electrical path, wherein the second electrical path comprises a resistor or an RC filter. [5] The vehicle power control system of claim 4, wherein the process further comprises: Determining, via the processor, a target frequency range of a frequency response; Determine, using the unit for measuring complex impedance, the frequency response over the target frequency range; Determining, via the processor, a state of health of the first battery cell based on the frequency response; and Determining, via the processor, that a difference between the state of health of the first battery cell and a state of health estimation map exceeds a battery imbalance threshold, wherein the first battery cell is controlled based on the state of health of the first battery cell. [6] The vehicle power control system of claim 1, wherein the complex impedance measuring unit is a device configured to apply an AC input signal to the first battery cell, measure an AC output signal of the first battery cell, and determine real and imaginary impedance values ​​based on the AC input signal and the AC output signal. [7] The vehicle power management system of claim 1, wherein the state of health of the first battery cell is a map or profile representing a remaining useful life of the first battery cell relative to at least one metric, wherein the remaining useful life of the first battery cell comprises at least one of: an internal impedance value, a number of expected remaining usage cycles, or a percentage of remaining charge, and wherein the at least one metric comprises: time, a cycle count, a temperature range, a voltage or current usage, or a capacity range of the first battery cell. [8] A computer-readable storage medium having computer-readable program code embodied therein, the computer-readable program code being executable by one or more computer processors to perform an operation comprising: Isolating, via a first insulation unit, a first battery cell from a plurality of battery cells; Determining, via a complex impedance measurement unit, a state of health of the first battery cell; and Controlling, via a controller, the first battery cell based on the state of health of the first battery cell. [9] The computer-readable storage medium of claim 8, wherein the process further comprises: Isolating, via a second insulation unit, a second battery cell from the plurality of battery cells Determining, via the complex impedance measurement unit, a state of health of the second battery cell; and Determining, via the controller, that a difference between the state of health of the first battery cell and the state of health of the second battery cell exceeds a state of health threshold, wherein the difference indicates that a remaining useful life of the first battery cell is less than a remaining useful life of the second battery cell, and wherein the first battery cell is controlled by isolating the first battery cell from the plurality of battery cells via the first isolation unit. [10] The computer-readable storage medium of claim 8, wherein the process further comprises: Determining, via the control, a target frequency range of a frequency response Determine, using the unit for measuring complex impedance, the frequency response over the target frequency range Determining, via the controller, a state of health of the first battery cell based on the frequency response Determining, via the controller, that a difference between the state of health of the first battery cell and a state of health estimation map exceeds a battery imbalance threshold, wherein the first battery cell is controlled based on the state of health of the first battery cell.

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