A battery cluster, energy storage system, uninterruptible power supply system, and electric vehicle

Abstract

The application provides a battery cluster, an energy storage system, an uninterruptible power supply system and an electric vehicle. The battery cluster comprises a metal shell and a first battery pack accommodated in the metal shell. The first battery pack comprises a battery module and an insulation monitoring circuit. A first end of the insulation monitoring circuit is connected to the metal shell, and a second end of the insulation monitoring circuit is connected to one end of the battery module. The insulation monitoring circuit determines insulation failure of the first battery pack when detecting that a current between the battery module and the metal shell is greater than a preset current threshold. The application can reduce the volume of the battery cluster.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a battery cluster, energy storage system, uninterruptible power supply system, and electric vehicle. Background Technology

[0002] The insulation of a battery pack is achieved by wrapping each battery cell with an insulating material (such as fiber tape) to isolate the electrolyte from the metal casing. Therefore, insulation failure in a battery pack can be understood as the insulation material surrounding the battery cell breaking down, creating an electrical connection between the electrolyte and the metal casing, resulting in a large current flowing through the metal casing. When a person comes into contact with the metal casing of this battery pack, a leakage circuit can form with the ground, posing a safety hazard.

[0003] A battery cluster consists of one or more battery packs connected in series, parallel, or series-parallel. Therefore, in the application of battery clusters, it is necessary to detect whether the insulation of the battery packs has failed. In the existing technology, insulation failure detection of battery packs is carried out using methods such as... Figure 1 The residual current device (RCD) shown is used for real-time detection. The RCD is positioned at both the positive and negative output terminals of PACK1, and it monitors the current at both terminals in real time. When the difference between the current at the positive and negative output terminals of PACK1 exceeds a certain threshold, the RCD determines that the insulation of PACK1 has failed. It can be seen that existing battery pack insulation failure detection requires a large RCD, resulting in a relatively large battery pack size. Summary of the Invention

[0004] This application provides a battery cluster, energy storage system, uninterruptible power supply system, and electric vehicle that can reduce the size of the battery cluster.

[0005] In a first aspect, embodiments of this application provide a battery cluster, which includes a metal casing and a first battery pack housed within the metal casing. The first battery pack includes a battery module and an insulation monitoring circuit.

[0006] The insulation detection circuit has a first end connected to the metal casing and a second end connected to one end of the battery module. When the insulation detection circuit detects that the current between the battery module and the metal casing is greater than a preset current threshold, it determines that the insulation of the first battery pack has failed.

[0007] In this embodiment, an insulation detection circuit is provided in the battery pack. Specifically, this circuit determines whether the battery pack's insulation has failed by detecting whether the current between the battery module and the metal casing exceeds a preset current threshold. Unlike existing technologies that use an RCD to detect the current at the positive and negative terminals of the battery pack in real time to determine insulation failure, this embodiment provides a new method for detecting battery pack insulation by changing the connection relationship of the insulation detection circuit. This eliminates the need for a bulky RCD and allows for the use of a smaller insulation detection circuit. Therefore, implementing this embodiment can reduce the size of the battery pack.

[0008] In conjunction with the first aspect, in a first possible implementation, the first battery pack further includes a first power conversion circuit, a second power conversion circuit, and a transformer housed within a metal casing, wherein the transformer is disposed between the first power conversion circuit and the second power conversion circuit, and the transformer includes a first winding, a second winding, and a third winding.

[0009] In a specific implementation, the first and second terminals of the first power conversion circuit are respectively connected to the two ends of the battery module, the third and fourth terminals of the first power conversion circuit are respectively connected to the two ends of the first winding, the first and second terminals of the second power conversion circuit are respectively connected to the two ends of the second winding, and the third and fourth terminals of the insulation detection circuit are respectively connected to the two ends of the third winding.

[0010] In this embodiment, a third winding is added to the transformer to power an insulation detection circuit. This circuit determines whether the battery pack's insulation has failed by detecting whether the current between the battery module and the metal casing exceeds a preset current threshold. The battery cluster provided in this embodiment does not require an additional power source, further reducing its size.

[0011] In conjunction with the first possible implementation of the first aspect, in the second possible implementation, the insulation detection circuit includes a current sampling sub-circuit and a rectifier sub-circuit; wherein, the first input terminal and the second input terminal of the rectifier sub-circuit are respectively connected to the two ends of the third winding, the first output terminal of the rectifier sub-circuit is connected to the current sampling sub-circuit, and the second output terminal of the rectifier sub-circuit is connected to the metal casing or the battery module.

[0012] In a third possible implementation, in conjunction with the first aspect or any of the above possible implementations of the first aspect, the insulation detection circuit includes a switching sub-circuit that is turned on when an insulation detection start signal is received.

[0013] In conjunction with the third possible implementation of the first aspect, in the fourth possible implementation, the insulation detection circuit further includes a control sub-circuit, which sends an insulation detection start signal to the switching sub-circuit when the battery cluster is in a non-charging and non-discharging state.

[0014] In a fifth possible implementation, in conjunction with the first aspect or any of the above possible implementations of the first aspect, the battery cluster further includes a communication line, and the first battery pack further includes a first battery management circuit; wherein the first battery management circuit is used to connect to the battery control circuit via the communication line.

[0015] In practice, the first battery management circuit sends an insulation failure warning signal to the battery control circuit when the insulation of the first battery pack fails.

[0016] In conjunction with the fifth possible implementation of the first aspect, in the sixth possible implementation, the first battery management circuit also sends the position of the first battery pack in the battery cluster to the battery control circuit.

[0017] In conjunction with the fifth possible implementation of the first aspect, in the seventh possible implementation, the battery cluster further includes a second battery pack and a battery control circuit, wherein the second battery pack includes a second battery management circuit.

[0018] In a specific implementation, the first end of the second battery management circuit is connected to the first battery management circuit, and the first battery management circuit sends the position of the first battery pack relative to the second battery pack to the second battery management circuit; the second end of the second battery management circuit is connected to the battery control circuit, and the second battery management circuit sends the position of the second battery pack in the battery cluster and the position of the first battery pack relative to the second battery pack to the battery control circuit. At this time, the battery control circuit can determine the position of the first battery pack in the battery cluster.

[0019] Secondly, embodiments of this application provide an energy storage system, which includes an energy storage converter and a battery cluster in combination with the first aspect or any of the possible implementations of the first aspect, wherein the battery cluster is connected to the energy storage converter.

[0020] Thirdly, embodiments of this application provide an uninterruptible power supply system, which includes an AC / DC converter, a DC / AC converter, and a battery cluster in combination with the first aspect or any of the possible implementations of the first aspect, wherein the battery cluster is connected to the AC / DC converter and the DC / AC converter.

[0021] Fourthly, embodiments of this application provide an electric vehicle, which includes an electric motor and a battery cluster in combination with the first aspect or any of the possible implementations of the first aspect, wherein the battery cluster is used to provide power to the electric motor.

[0022] It should be understood that the implementations and beneficial effects of the above-mentioned aspects of this application can be referenced from each other. Attached Figure Description

[0023] Figure 1 A structural block diagram of a battery cluster provided for the prior art;

[0024] Figure 2 A structural block diagram of an energy storage system provided in an embodiment of this application;

[0025] Figure 3 A structural block diagram of an uninterruptible power supply system provided in an embodiment of this application;

[0026] Figure 4 A structural block diagram of an electric vehicle provided in an embodiment of this application;

[0027] Figure 5 This is a structural block diagram of a battery cluster provided in an embodiment of this application;

[0028] Figure 6 A circuit diagram of an insulation detection circuit provided in an embodiment of this application;

[0029] Figure 7 Another structural block diagram of the battery cluster provided in the embodiments of this application;

[0030] Figure 8 Another circuit diagram of the insulation detection circuit provided in the embodiments of this application;

[0031] Figure 9 Another structural block diagram of the battery cluster provided in the embodiments of this application;

[0032] Figure 10 This is another structural block diagram of the battery cluster provided in the embodiments of this application. Detailed Implementation

[0033] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0034] To better understand this application, the relationship between batteries, battery clusters, battery packs, and battery modules will first be explained.

[0035] In the field of battery technology, "battery" is a general term. A battery may include a battery cluster or multiple battery clusters connected in parallel to a DC bus.

[0036] A battery cluster includes a battery pack, or multiple battery packs connected in series, parallel, or series-parallel configurations.

[0037] A battery pack includes a battery module and a battery management system (BMS), or it may include multiple battery modules managed uniformly by the BMS. The battery pack can also be called a PACK. A battery pack has a positive electrode, a negative electrode, an electrolyte, and a metal casing, which can be, for example, an aluminum casing or a steel casing.

[0038] A battery module may include a single battery cell, or multiple battery cells connected in series, parallel, or series-parallel configurations. In this case, one or more cells are encapsulated together within the same housing frame. For example, in addition to battery cells, a battery module may also include circuitry with specific functional outputs, such as battery short-circuit protection circuitry, battery temperature detection circuitry, etc.

[0039] A battery cell refers to a single electrochemical cell containing positive and negative electrodes, which is generally not used directly. A battery cell is the smallest energy storage unit in a battery.

[0040] The implementation of the technical solution of this application will be further described in detail below with reference to the accompanying drawings.

[0041] See Figure 2 , Figure 2 This is a structural block diagram of an energy storage system provided in an embodiment of this application. Figure 2 As shown, the energy storage system 21 provided in this application embodiment includes a battery cluster 211 and an energy storage converter (PowerConversion System, PCS) 212 connected to the battery cluster 211.

[0042] In specific implementations, multiple battery clusters 211 can be connected in series, parallel, or in a series-parallel configuration to form lithium batteries, lithium-ion batteries, lead-acid batteries, sodium-ion batteries, nickel-cadmium batteries, or nickel-metal hydride batteries, etc. In other words, the embodiments of this application do not limit the electrolyte injected into the battery clusters.

[0043] For example, the battery cluster 211 includes a battery control circuit, also known as a battery control unit (BCU), which is a component of the BMS and can be referred to as the host of the BMS. For example, the battery control circuit can measure the total voltage and total current of multiple battery clusters 211, and can control the charging and discharging of each battery cluster 211, as well as evaluate the state of charge value of each battery cluster 211, etc.

[0044] The energy storage converter 212 can convert AC power to DC power during the charging process of the battery cluster 211. Alternatively, the energy storage converter 212 can convert DC power to AC power during the discharging process of the battery cluster 211.

[0045] For example, the energy storage system 21 can be specifically applied in photovoltaic energy storage scenarios or wind power energy storage scenarios. Taking the application of the energy storage system 21 in a photovoltaic energy storage scenario as an example, the energy storage system 21 is connected to a photovoltaic inverter, which converts the direct current generated by the photovoltaic modules into a first alternating current. At this time, the energy storage converter 212 can convert the first alternating current back into a first direct current and transmit the first direct current to the battery cluster 211, thereby charging the battery cluster 211. The energy storage system 21 is also connected to an AC power grid or an AC load. When the output power of the photovoltaic modules is insufficient, the energy storage converter 212 can convert the second direct current output by the battery cluster 211 into a second alternating current and connect the second alternating current to the AC power grid, or provide the second alternating current to the AC load, thereby discharging the battery cluster 211.

[0046] Optionally, the energy storage system 21 provided in this application embodiment can also be specifically applied to consumer electronics (such as smartphones, smartwatches, smart bracelets, and Bluetooth headsets, etc.), in which case the battery cluster 211 can be specifically understood as the battery cluster corresponding to the consumer electronics.

[0047] The energy storage system 21 provided in this embodiment differs from existing energy storage systems in that the battery cluster 211 included in the energy storage system 21 is different from that included in existing energy storage systems. Specifically, this embodiment includes an insulation detection circuit in the battery cluster 211. This insulation detection circuit determines whether the insulation of the battery cluster 211 has failed by detecting whether the current between the battery module and the metal casing of the battery cluster exceeds a preset current threshold. In other words, this embodiment specifically detects whether the insulation of the battery pack has failed by changing the detection method of the insulation detection circuit.

[0048] In some feasible implementations, the battery clusters provided in this application embodiment can be used in uninterruptible power systems (UPS). See also Figure 3 , Figure 3 This is a structural block diagram of an uninterruptible power supply system provided in an embodiment of this application. Figure 3 As shown, the uninterruptible power supply system 31 includes a battery cluster 311, an AC / DC converter 312, and a DC / AC converter 313.

[0049] The AC / DC converter 312 has its input connected to the AC mains, and its output connected to the battery pack 311 and the input of the DC / AC converter 313. The output of the DC / AC converter 313 is connected to the AC load. For example, when the AC mains output voltage is normal, the AC / DC converter 312 and the DC / AC converter 313 regulate the AC mains output voltage and supply it to the AC load. In this case, the uninterruptible power supply system 31 can act as a voltage regulator and can also charge the battery pack 311 simultaneously. When the AC mains output is interrupted, such as due to a grid fault or maintenance outage, the battery pack 311 in the uninterruptible power supply system 31 outputs a third DC power to the DC / AC converter 313. The DC / AC converter 313 converts this third DC power into a third AC power and supplies it to the AC load, thereby maintaining the normal operation of the AC load and protecting the load's software and hardware from damage.

[0050] In some feasible implementations, the battery clusters provided in this application can be used in electric vehicles. See also Figure 4 , Figure 4 This is a structural block diagram of an electric vehicle provided in an embodiment of this application. Figure 4 As shown, the electric vehicle 41 includes a battery cluster 411 and a motor 412. The battery cluster 411 is connected to the motor 412 through an inverter. Specifically, the battery cluster 411 outputs a fourth DC power to the inverter, which converts the fourth DC power into a fourth AC power. This fourth AC power is used to drive the motor, thereby providing power to the electric vehicle.

[0051] The specific structure of the battery cluster is described below with reference to the accompanying drawings.

[0052] See Figure 5 , Figure 5 This is a structural block diagram of a battery cluster provided in an embodiment of this application. Figure 5 As shown, the battery cluster includes a first battery pack 511, wherein the first battery pack 511 includes a metal casing 5111, a battery module 5112 housed within the metal casing 5111, and an insulation detection circuit 5113.

[0053] In a specific implementation, the first end of the insulation detection circuit 5113 is connected to the metal casing 5111, which, for example, can be an aluminum casing, a steel casing, or an iron casing. The second end of the insulation detection circuit 5113 is connected to one end of the battery module 5112. Figure 5 Taking the second end of the insulation detection circuit 5113 connected to the negative terminal of the battery module 5112 as an example, in some feasible implementations, the second end of the insulation detection circuit 5113 can also be connected to the positive terminal of the battery module 5112.

[0054] The third and fourth terminals of the insulation detection circuit 5113 are respectively connected to the two ends of the power supply 512.

[0055] Power supply 512 outputs voltage to the third and fourth terminals of insulation detection circuit 5113. If the insulation of the first battery pack 511 fails, power supply 512 forms a closed loop through insulation detection circuit 5113, battery module 5112, and metal casing 5111. If insulation detection circuit 5113 detects that the current in this closed loop is greater than a preset current threshold, that is, if insulation detection circuit 5113 detects that the current between battery module 5112 and metal casing 5111 is greater than the preset current threshold, then insulation failure of the first battery pack 511 is determined. For example, this preset current threshold can be pre-set according to the specific application scenario of the battery pack. For instance, if the battery pack is used in an electric vehicle, the preset current threshold can be set according to the insulation standard of the electric vehicle's power battery.

[0056] Understandable, Figure 5 Taking a battery cluster specifically including a first battery pack as an example, in some feasible implementations, the battery cluster may include multiple first battery packs.

[0057] In this embodiment, an insulation detection circuit is provided in the battery pack. Specifically, this circuit determines whether the battery pack's insulation has failed by detecting whether the current between the battery module and the metal casing exceeds a preset current threshold. Unlike existing technologies that use an RCD to detect the current at the positive and negative terminals of the battery pack in real time to determine insulation failure, this embodiment provides a new method for battery pack insulation detection by changing the connection relationship of the insulation detection circuit. This eliminates the need for a bulky RCD and allows for the use of a smaller insulation detection circuit. Therefore, implementing this embodiment can reduce the size of the battery pack.

[0058] For example, the following is in conjunction with the appendix Figure 6 The specific structure of the insulation detection circuit 5113 is described below.

[0059] In some feasible implementations, see Figure 6 , Figure 6A circuit diagram of an insulation detection circuit provided in an embodiment of this application. Figure 6 As shown, the insulation detection circuit 5113 includes a current sampling sub-circuit 51131. Figure 6 The current sampling sub-circuit 51131 is specifically implemented as a resistor R. 61 For example, one end of the power supply 512 is connected to resistor R. 61 One end, resistor R 61 The other end is connected to point B. Optionally, the current sampling sub-circuit 51131 can also be implemented as a current sensor.

[0060] Optionally, in some feasible embodiments, the insulation detection circuit 5113 further includes a switching sub-circuit 51132, which, along with the current sampling sub-circuit 51131, is connected in series between point A and point B. For example,... Figure 6 As shown, one end of the switch sub-circuit 51132 is connected to the other end of the power supply 512, and the other end of the switch sub-circuit 51132 is connected to point A. Alternatively, resistor R... 61 One end is connected to one end of the power supply 512, and the resistor R 61 The other end is connected to one end of the switch sub-circuit 51132, and the other end of the switch sub-circuit 51132 is connected to point B.

[0061] The switching sub-circuit 51132 is turned on when it receives an insulation detection start signal. For example, the insulation detection start signal may be sent to the switching sub-circuit 51132 by the battery control circuit in the battery pack.

[0062] The switching sub-circuit 51132 can be specifically implemented as a solid-state switch and a semiconductor switch. The semiconductor switch includes, but is not limited to, transistors, metal-oxide-semiconductor field-effect transistors (MOSFETs), and insulated-gate bipolar transistors (IGBTs).

[0063] For example, the insulation detection circuit 5113 also includes a filter capacitor C. 61 Capacitor C 61 The two ends are connected in parallel across the two ends of power supply 512 to filter the output voltage of power supply 512.

[0064] Optionally, in some feasible implementations, the insulation detection circuit further includes a control sub-circuit 51133, which can send an insulation detection start signal to the switch sub-circuit 51132 when the battery cluster is in a non-charging and non-discharging state. It is understood that the battery cluster being in a non-charging and non-discharging state refers to the battery cluster being in a float charging, powered-on, or standby state.

[0065] Optionally, if point A is the first terminal of the insulation detection circuit, then point B is the second terminal of the insulation detection circuit. In this case, the switch sub-circuit 51132 is connected to the metal casing, and the resistor R... 61 The other end is connected to the battery module. Alternatively, if point A is the second end of the insulation detection circuit, then point B is the first end of the insulation detection circuit. In this case, the switch sub-circuit 51132 is connected to the battery module, and the resistor R... 61 The other end is connected to the metal casing.

[0066] Optionally, in some feasible implementations, see [link to relevant documentation]. Figure 7 , Figure 7 This is another structural block diagram of the battery cluster provided in an embodiment of this application. For example... Figure 7 As shown, the battery pack includes a first battery pack 711, which includes a metal casing 7111 and a battery module 7112, an insulation detection circuit 7113, a first power conversion circuit 7114, a second power conversion circuit 7115, and a transformer housed within the metal casing 7111. The transformer is located between the first power conversion circuit 7114 and the second power conversion circuit 7115, and includes a first winding L. 71 Second winding L 72 and the third winding L 73 .

[0067] In a specific implementation, the first and second terminals of the first power conversion circuit 7114 are respectively connected to the two ends of the battery module 7112, and the third and fourth terminals of the first power conversion circuit 7114 are respectively connected to the first winding L. 71 The first and second ends of the second power conversion circuit 7115 are respectively connected to the second winding L. 72 At both ends, the third and fourth terminals of the second power conversion circuit 7115 are connected to the positive and negative busbars of the battery pack, respectively.

[0068] Among them, the first power conversion circuit 7114 and the first winding L 71 Second winding L 72The second power conversion circuit 7115 is a component of the active balancing circuit of the battery module 7112. This active balancing circuit maintains the voltage difference between the first battery pack 711 and other battery packs in the battery cluster within a preset range. For example, this active balancing circuit can be specifically implemented as an LLC circuit, a full-bridge converter circuit, a half-bridge converter circuit, a forward converter circuit, or a flyback converter circuit. The specific implementations of the first power conversion circuit 7114 and the second power conversion circuit 7115 can refer to LLC circuits, full-bridge converter circuits, half-bridge converter circuits, forward converter circuits, or flyback converter circuits, and will not be elaborated here.

[0069] The first terminal of the insulation detection circuit 7113 is connected to the metal casing 7111, and the second terminal of the insulation detection circuit 7113 is connected to one end of the battery module 7112. Figure 7 Taking the second end of the insulation detection circuit 7113 connected to the negative terminal of the battery module 7112 as an example, in some feasible implementations, the second end of the insulation detection circuit 7113 can also be connected to the positive terminal of the battery module 7112.

[0070] The third and fourth terminals of the insulation detection circuit 7113 are connected to the third winding L. 73 The two ends. Distinguished from Figure 5 The third and fourth terminals of the insulation detection circuit 5113 shown in the figure are respectively connected to the two ends of the power supply 512. In the embodiment of this application, the third and fourth terminals of the insulation detection circuit 7113 are connected to the third winding L. 73 At this time, the voltage of the insulation detection circuit 7113 comes from the third winding L. 73 .

[0071] Third winding L 73 The voltage across the terminals is applied to the third and fourth terminals of the insulation detection circuit 7113. If the insulation of the first battery pack 711 fails, the third winding L... 73 The insulation detection circuit 7113, battery module 7112, and metal casing 7111 form a closed loop. If the insulation detection circuit 7113 detects that the current in the closed loop is greater than a preset current threshold, that is, the insulation detection circuit 7113 detects that the current between battery module 7112 and metal casing 7111 is greater than the preset current threshold, thereby determining that the insulation of the first battery pack 711 has failed.

[0072] In this embodiment, a third winding is added to the transformer of the active balancing circuit, and this third winding is used to supply power to the insulation detection circuit. This insulation detection circuit determines whether the battery pack's insulation has failed by detecting whether the current between the battery module and the metal casing exceeds a preset current threshold. This differs from... Figure 5 The battery cluster shown in the figure does not require an additional power source, and the size of the battery cluster can be further reduced.

[0073] The following is in conjunction with the appendix Figure 8 The specific structure of the insulation detection circuit 7113 is described below.

[0074] In some feasible implementations, see Figure 8 , Figure 8 This is another circuit diagram of the insulation detection circuit provided in an embodiment of this application. (See diagram below.) Figure 8 As shown, the insulation detection circuit 7113 includes a current sampling sub-circuit 71131 and a rectifier sub-circuit 71132.

[0075] The rectifier circuit 71132 includes diode D. 81 diode D 82 diode D 83 and diode D 84 Diode D 81 anode and diode D 82 The cathode is connected to the third winding L 73 One end; diode D 83 anode and diode D 84 The cathode is connected to the third winding L 73 The other end.

[0076] Diode D 82 anode and diode D 84 The anode connection current sampling sub-circuit 71131, Figure 8 The current sampling sub-circuit 71131 is specifically implemented as a resistor R. 81 For example, diode D 82 anode and diode D 84 Anode connection resistor R 81 One end, resistor R 81 The other end is connected to point D. Optionally, the current sampling sub-circuit 71131 can also be implemented as a current sensor.

[0077] It is understood that, in the embodiments of this application, the rectifier circuit is specifically implemented as four diodes. In some feasible implementations, the rectifier circuit can also be specifically implemented as four semiconductor switches.

[0078] Optionally, the insulation detection circuit 7113 also includes a filter capacitor C. 81 Capacitor C 81 The two ends are connected in parallel between the first output terminal and the second output terminal of the rectifier circuit 71132 to filter the DC power obtained after rectification by the rectifier circuit 71132.

[0079] In this embodiment of the application, the rectifier circuit 71132 is paired with the third winding L 73The supplied power is rectified.

[0080] Optionally, in some feasible embodiments, the insulation detection circuit 7113 further includes a switching sub-circuit 71133, wherein the switching sub-circuit 71133 is connected between point C and the rectifier sub-circuit 71132 or point D and the rectifier circuit 71132. For example, one end of the switching sub-circuit 71133 is connected to diode D. 81 cathode and diode d 83 The cathode of the switch circuit 71133 is connected to point C, and the other end of the switch circuit 71133 is connected to point D and resistor R. 81 Between. Or, the switch sub-circuit 71133 is connected to resistor R. 81 Between and the rectifier circuit 71132.

[0081] The switching sub-circuit 71133 is turned on when it receives an insulation detection start signal. For example, the insulation detection start signal may be sent to the switching sub-circuit 71133 by the battery control circuit in the battery cluster.

[0082] The switching sub-circuit 71133 can be specifically implemented as a solid-state switch and a semiconductor switch, wherein the semiconductor switch includes, but is not limited to, transistors, MOSFETs and IGBTs.

[0083] Optionally, in some feasible implementations, the insulation detection circuit 7113 may further include a control sub-circuit 71134, which may send an insulation detection start signal to the switch sub-circuit 71133 when the battery cluster is in a non-charging and non-discharging state.

[0084] Optionally, if point C is the first terminal of the insulation detection circuit, then point D is the second terminal of the insulation detection circuit. In this case, diode D... 81 cathode and diode D 83 The cathode is connected to the metal casing, and the resistance R 81 The other end is connected to the battery module. Alternatively, if point C is the second terminal of the insulation detection circuit, then point D is the first terminal of the insulation detection circuit, in which case diode D... 81 cathode and diode D 83 The cathode is connected to the battery module, and the resistor R 81 The other end is connected to the metal casing.

[0085] Optionally, in some feasible implementations, see [link to relevant documentation]. Figure 9 , Figure 9 This is another structural block diagram of the battery cluster provided in an embodiment of this application. For example... Figure 9As shown, the battery cluster includes a metal casing 911 and a plurality of first battery packs, such as first battery pack 912A, first battery pack 912B and first battery pack 912C, housed within the metal casing 911.

[0086] Each first battery pack is specifically implemented as follows Figure 7 Taking the first battery pack shown as an example, each first battery pack includes a metal casing, a battery module, an insulation detection circuit, a first power conversion circuit, a transformer, and a second power conversion circuit. Each first battery pack also includes a first battery management circuit. In this application, the battery management circuit is also referred to as a battery management unit (BMU). Therefore, the first battery management circuit can also be called the first battery management unit, and the second battery management circuit can also be called the second battery management unit. The first battery management circuit is a component of the BMS and can be referred to as a slave device of the BMS.

[0087] In this embodiment, the metal casing 911 of the battery cluster and the metal casing of each first battery pack are at the same potential point. Specifically, the insulation detection circuit in each first battery pack is connected to the metal casing corresponding to that first battery pack, and then the metal casing of each first battery pack is connected to the metal casing 911 of the battery cluster, that is, the metal casing of each first battery pack and the metal casing 911 of the battery cluster are electrically connected.

[0088] In its specific implementation, the first battery pack 912A includes a battery module 912A1, an insulation detection circuit 912A2, a first power conversion circuit 912A3, a transformer, a second power conversion circuit 912A4, and a first battery management circuit 912A5, wherein the transformer includes a first winding L. 91 Second winding L 92 and the third winding L 93 .

[0089] At this time, the first and second terminals of the first power conversion circuit 912A3 are connected in parallel to the two ends of the battery module 912A1, respectively, and the third and fourth terminals of the first power conversion circuit 912A3 are connected to the first winding L, respectively. 91 The two ends. The second winding L 92 The two ends of the first power conversion circuit 912A4 are respectively connected to the first and second ends of the second power conversion circuit 912A4, and the third and fourth ends of the second power conversion circuit 912A4 are respectively connected to the positive bus and negative bus of the battery pack. The first battery management circuit 912A5 is packaged together with the battery module 912A1, and the first battery management circuit 912A5 is connected to the battery control circuit 913 via communication line 1. For example, this communication line 1 can be a CAN communication line.

[0090] The first terminal of the insulation detection circuit 912A2 is connected to the metal casing 911, the second terminal of the insulation detection circuit 912A2 is connected to one end of the battery module 912A1, and the third and fourth terminals of the insulation detection circuit 912A2 are connected to the third winding L. 93 The two ends.

[0091] The first battery management circuit 912A5 can send a first insulation failure warning signal to the battery control circuit 913 in the event of insulation failure of the first battery pack 912A.

[0092] Optionally, the first battery management circuit 912A5 may also send the position of the first battery pack 912A within the battery cluster to the battery control circuit 913. Optionally, the first battery management circuit 912A5 may send the position of the first battery pack 912A within the battery cluster to the battery control circuit 913 before sending the first insulation failure warning signal to the battery control circuit 913. Alternatively, the first battery management circuit 912A5 may, upon determining that the first battery pack 912A has suffered an insulation failure, simultaneously send the first insulation failure warning signal and the position of the first battery pack 912A within the battery cluster to the battery control circuit 913. Alternatively, the first battery management circuit 912A5 may send the position of the first battery pack 912A within the battery cluster to the battery control circuit 913 after sending the first insulation failure warning signal to the battery control circuit 913. For example, if the first battery pack 912A, the first battery pack 912B, and the first battery pack 912C are arranged sequentially from left to right, then the first battery pack 912A is located at the leftmost position in the battery cluster.

[0093] Similarly, the first battery pack 912B includes a battery module 912B1, an insulation detection circuit 912B2, a first power conversion circuit 912B3, a transformer, a second power conversion circuit 912B4, and a first battery management circuit 912B5, wherein the transformer includes a first winding L. 94 Second winding L 95 and the third winding L 96 .

[0094] At this time, the first and second terminals of the first power conversion circuit 912B3 are connected in parallel to the two ends of the battery module 912B1, respectively, and the third and fourth terminals of the first power conversion circuit 912B3 are connected to the first winding L, respectively. 94 The two ends. The second winding L 95The two ends of the first power conversion circuit 912B4 are respectively connected to the first and second ends of the second power conversion circuit 912B4, and the third and fourth ends of the second power conversion circuit 912B4 are respectively connected to the positive bus and negative bus of the battery pack. Among them, the first battery management circuit 912B5 is packaged together with the battery module 912B1, and the first battery management circuit 912B5 is connected to the battery control circuit 913 through the communication line 1.

[0095] The first terminal of the insulation detection circuit 912B2 is connected to the metal casing 911, the second terminal of the insulation detection circuit 912B2 is connected to one end of the battery module 912B1, and the third and fourth terminals of the insulation detection circuit 912B2 are connected to the third winding L. 96 The two ends.

[0096] The first battery management circuit 912B5 can send a second insulation failure warning signal to the battery control circuit 913 in the event of insulation failure of the first battery pack 912B.

[0097] Optionally, the first battery management circuit 912B5 may also send the position of the first battery pack 912B within the battery cluster to the battery control circuit 913. Optionally, the first battery management circuit 912B5 may send the position of the first battery pack 912B within the battery cluster to the battery control circuit 913 before sending the second insulation failure warning signal. Alternatively, the first battery management circuit 912B5 may, upon determining that the first battery pack 912B has suffered insulation failure, simultaneously send the second insulation failure warning signal and the position of the first battery pack 912B within the battery cluster to the battery control circuit 913. Or, the first battery management circuit 912B5 may send the position of the first battery pack 912B within the battery cluster to the battery control circuit 913 after sending the second insulation failure warning signal. For example, if the first battery pack 912A, the first battery pack 912B, and the first battery pack 912C are arranged sequentially from left to right, then the first battery pack 912B is located in the middle of the battery cluster.

[0098] The first battery pack 912C includes a battery module 912C1, an insulation detection circuit 912C2, a first power conversion circuit 912C3, a transformer, a second power conversion circuit 912C4, and a first battery management circuit 912C5, wherein the transformer includes a first winding L. 97 Second winding L 98 and the third winding L 99 .

[0099] At this time, the first and second terminals of the first power conversion circuit 912C3 are connected in parallel to the two ends of the battery module 912C1, and the third and fourth terminals of the first power conversion circuit 912C3 are connected to the first winding L, respectively.97 The two ends. The second winding L 98 The two ends of the first power conversion circuit 912C4 are connected to the first and second ends of the second power conversion circuit 912C4, respectively. The third and fourth ends of the second power conversion circuit 912C4 are connected to the positive bus and negative bus of the battery pack, respectively. The first battery management circuit 912C5 is packaged together with the battery module 912C1, and the first battery management circuit 912C5 is connected to the battery control circuit 913 through communication line 1.

[0100] The first terminal of the insulation detection circuit 912C2 is connected to the metal casing 911, the second terminal of the insulation detection circuit 912C2 is connected to one end of the battery module 912C1, and the third and fourth terminals of the insulation detection circuit 912C2 are connected to the third winding L. 99 The two ends.

[0101] The first battery management circuit 912C5 can send a third insulation failure warning signal to the battery control circuit 913 in the event of insulation failure of the first battery pack 912C.

[0102] Optionally, the first battery management circuit 912C5 may also send the position of the first battery pack 912C within the battery cluster to the battery control circuit 913. Optionally, the first battery management circuit 912C5 may send the position of the first battery pack 912C within the battery cluster to the battery control circuit 913 before sending the third insulation failure warning signal. Alternatively, the first battery management circuit 912C5 may, upon determining that the first battery pack 912C has experienced an insulation failure, simultaneously send the third insulation failure warning signal and the position of the first battery pack 912C within the battery cluster to the battery control circuit 913. Or, the first battery management circuit 912C5 may send the position of the first battery pack 912C within the battery cluster to the battery control circuit 913 after sending the third insulation failure warning signal. For example, if the first battery pack 912A, the first battery pack 912B, and the first battery pack 912C are arranged sequentially from left to right, then the first battery pack 912C is located at the far right of the battery cluster.

[0103] In some feasible implementations, the battery cluster also includes a power distribution box 914. The power distribution box 914 can distribute the energy output by the battery.

[0104] For example, when the battery control circuit 913 determines that the battery pack is in a non-charging and non-discharging state, it initiates insulation detection for each of the first battery packs. For instance, in the first battery pack 912A, the battery control circuit 913 sends an insulation detection start signal to the first battery management circuit 912A5. The first battery management circuit 912A5 then sends this insulation start signal to the insulation detection circuit 912A2. If the insulation detection circuit 912A2 detects that the current between the battery module 912A1 and the metal casing 911 exceeds a preset current threshold, the insulation detection circuit 912A2 sends a first insulation failure warning signal through the first battery management circuit 912A5. Similarly, the generation process of the insulation failure warning signal for the first battery pack 912B and the first battery pack 912C can be referenced to that of the first battery pack 912A, and will not be elaborated here.

[0105] In this embodiment, the physical location of each first battery pack within the battery cluster can be determined using a communication line. When the insulation detection circuit detects an insulation failure in the corresponding first battery pack, the first battery pack can be quickly replaced, which is beneficial for improving production and maintenance efficiency.

[0106] Optionally, in some feasible implementations, see [link to relevant documentation]. Figure 10 , Figure 10 This is another structural block diagram of the battery cluster provided in an embodiment of this application. For example... Figure 10 As shown, the battery cluster includes a metal casing 1011 and a plurality of first battery packs, such as first battery pack 1012A and first battery pack 1012B, housed within the metal casing 1011.

[0107] Each first battery pack is specifically implemented as follows Figure 7 Taking the first battery pack shown as an example, each first battery pack includes a battery module, an insulation detection circuit, a first power conversion circuit, a transformer, and a second power conversion circuit, and each first battery pack also includes a first battery management circuit.

[0108] In this embodiment, the metal casing 1011 of the battery cluster and the metal casing of each first battery pack are at the same potential point. Specifically, the insulation detection circuit in each first battery pack is connected to the metal casing corresponding to that first battery pack, and then the metal casing of each first battery pack is connected to the metal casing 1011 of the battery cluster, that is, the metal casing of each first battery pack and the metal casing 1011 of the battery cluster are electrically connected.

[0109] In its specific implementation, the first battery pack 1012A includes a battery module 1012A1, an insulation detection circuit 1012A2, a first power conversion circuit 1012A3, a transformer, a second power conversion circuit 1012A4, and a first battery management circuit 1012A5, wherein the transformer includes a first winding L.101 Second winding L 102 and the third winding L 103 .

[0110] At this time, the first and second terminals of the first power conversion circuit 1012A3 are connected in parallel to the two ends of the battery module 1012A1, respectively, and the third and fourth terminals of the first power conversion circuit 1012A3 are connected to the first winding L, respectively. 101 The two ends. The second winding L 102 The first and second terminals of the second power conversion circuit 1012A4 are connected to each other. The third and fourth terminals of the second power conversion circuit 1012A4 are connected to the positive and negative busbars of the battery pack, respectively. The first battery management circuit 1012A5 is packaged together with the battery module 1012A1. The first battery management circuit 1012A5 is connected to the battery control circuit 1014 via communication line 2. For example, this communication line 2 can be a CAN communication line.

[0111] The first terminal of the insulation detection circuit 1012A2 is connected to the metal casing 1011, the second terminal of the insulation detection circuit 1012A2 is connected to one end of the battery module 1012A1, and the third and fourth terminals of the insulation detection circuit 1012A2 are connected to the third winding L. 103 The two ends.

[0112] The first battery pack 1012B includes a battery module 1012B1, an insulation detection circuit 1012B2, a first power conversion circuit 1012B3, a transformer, a second power conversion circuit 1012B4, and a first battery management circuit 1012B5, wherein the transformer includes a first winding L. 104 Second winding L 105 and the third winding L 106 .

[0113] At this time, the first and second terminals of the first power conversion circuit 1012B3 are connected in parallel to the two ends of the battery module 1012B1, and the third and fourth terminals of the first power conversion circuit 1012B3 are connected to the first winding L, respectively. 104 The two ends. The second winding L 105 The two ends of the first power conversion circuit 1012B4 are connected to the first and second ends of the second power conversion circuit 1012B4. The third and fourth ends of the second power conversion circuit 1012B4 are connected to the positive and negative busbars of the battery pack, respectively. The first battery management circuit 1012B5 is packaged together with the battery module 1012B1, and is connected to the first end of the first battery management circuit 1012A5 in the first battery pack 1012A. The first battery management circuit 1012B5 is connected to the battery control circuit 1014 via communication line 2. For example, this communication line 2 can be a CAN communication line.

[0114] The first terminal of the insulation detection circuit 1012B2 is connected to the metal casing 1011, the second terminal of the insulation detection circuit 1012B2 is connected to one end of the battery module 1012B1, and the third and fourth terminals of the insulation detection circuit 1012B2 are connected to the third winding L. 106 The two ends.

[0115] Furthermore, the battery cluster also includes a second battery pack 1013, which includes a battery module 10131 and a second battery management circuit 10132. The first terminal of the second battery management circuit 10132 is connected to the second terminal of the first battery management circuit 1012A5 in the first battery pack 1012A. The second battery management circuit 10132 can also be connected to the battery control circuit 1014 via a communication line 2. For example, this communication line 2 can be a CAN communication line.

[0116] Optionally, the structure of the second battery pack 1013 can also be specifically implemented as follows: Figure 7 The structure of the first battery pack is shown in the figure.

[0117] Similarly, the metal casing of the second battery pack 1013 and the metal casing 1011 of the battery cluster are also electrically connected.

[0118] In the event of an insulation failure in the first battery pack 1012A, the first battery management circuit 1012A5 can send a first insulation failure warning signal to the second battery management circuit 10132 in the second battery pack 1013.

[0119] For example, the first battery management circuit 1012A5 can also send the position of the first battery pack 1012A relative to the second battery pack 1013 to the second battery management circuit 10132 before or after sending the first insulation failure warning signal. The second battery pack 1013, the first battery pack 1012A, and the first battery pack 1012B are arranged sequentially from left to right. The first battery management circuit 1012A5 sends a first level to the second battery management circuit 10132, and the second battery management circuit 10132 determines that the first battery pack 1012A is to the right of the second battery pack 1013.

[0120] The second battery management circuit 10132 sends the position of the second battery pack 1013 within the battery cluster, and the position of the first battery pack 1012A relative to the second battery pack 1013, to the battery control circuit 1014. At this time, the battery control circuit 1014 can determine the position of the first battery pack 1012A within the battery cluster. For example, if the second battery pack 1013 is the first in the battery cluster, the battery control circuit 1014 can determine that the first battery pack 1012A is the second in the battery cluster.

[0121] In the event of an insulation failure in the first battery pack 1012B, the first battery management circuit 1012B5 can send a second insulation failure warning signal to the first battery management circuit 1012A5 in the first battery pack 1012A.

[0122] Similarly, the first battery management circuit 1012B5 can also send the position of the first battery pack 1012B relative to the first battery pack 1012A5 to the first battery management circuit 1012A5 before or after sending the second insulation failure warning signal. The second battery pack 1013, the first battery pack 1012A, and the first battery pack 1012B are arranged sequentially from left to right. The first battery management circuit 1012B5 sends a first level signal to the first battery management circuit 1012A5, and the second battery management circuit 10132 determines that the first battery pack 1012B is to the right of the first battery pack 1012A.

[0123] The first battery management circuit 1012B5 sends the position of the second battery pack 1013 in the battery cluster, the position of the first battery pack 1012B relative to the second battery pack 1013, and the position of the first battery pack 1012B relative to the first battery pack 1012A to the battery control circuit 1014. At this time, the battery control circuit 1014 can determine the position of the first battery pack 1012B in the battery cluster. For example, if the second battery pack 1013 is the first in the battery cluster, the battery control circuit 1014 can determine that the first battery pack 1012A is the second in the battery cluster and the first battery pack 1012B is the third in the battery cluster.

[0124] In this embodiment, the communication line is used to transmit insulation failure warning signals. The physical location of each first battery pack is located by using the connection between the ordinary I / O ports of each battery management circuit. This does not occupy the communication resources of the communication line. When the insulation detection circuit detects the insulation failure of the corresponding first battery pack, the first battery pack can be quickly replaced, which is beneficial to improving production efficiency and maintenance efficiency.

[0125] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0126] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A battery cluster, characterized in that, The battery cluster includes multiple battery packs. A first battery pack within the multiple battery packs includes a metal casing and a battery module housed within the metal casing, as well as an insulation detection circuit. The battery module includes battery cells. The battery cluster also includes a communication line and a battery control circuit. The first battery pack further includes a first battery management circuit. The battery cluster also includes a second battery pack, which includes a second battery management circuit. The first battery management circuit is connected to the battery control circuit via the communication line. A first terminal of the second battery management circuit is connected to the first battery management circuit, and a second terminal of the second battery management circuit is connected to the battery control circuit. The first end of the insulation detection circuit is connected to the metal casing, and the second end of the insulation detection circuit is connected to one end of the battery module; the insulation detection circuit is used to determine the insulation failure of the first battery pack when the current between the battery module and the metal casing is greater than a preset current threshold. The first battery management circuit is used to send a first insulation failure warning signal to the second battery management circuit in the event of insulation failure of the first battery pack; The first battery management circuit is further configured to send the position of the first battery pack relative to the second battery pack to the second battery management circuit before or after sending the first insulation failure warning signal; The second battery management circuit is used to send the position of the second battery pack in the battery cluster and the position of the first battery pack relative to the second battery pack to the battery control circuit, so that the battery control circuit can determine the position of the first battery pack in the battery cluster.

2. The battery cluster according to claim 1, characterized in that, The first battery pack further includes a first power conversion circuit, a second power conversion circuit, and a transformer housed within the metal casing, wherein the transformer is disposed between the first power conversion circuit and the second power conversion circuit, and the transformer includes a first winding, a second winding, and a third winding; The first and second terminals of the first power conversion circuit are respectively connected to the two ends of the battery module, and the third and fourth terminals of the first power conversion circuit are respectively connected to the two ends of the first winding. The first and second terminals of the second power conversion circuit are respectively connected to the two ends of the second winding; The third and fourth terminals of the insulation detection circuit are respectively connected to the two ends of the third winding.

3. The battery cluster according to claim 2, characterized in that, The insulation detection circuit includes a current sampling sub-circuit and a rectifier sub-circuit; wherein... The first and second input terminals of the rectifier circuit are respectively connected to the two ends of the third winding, the first output terminal of the rectifier circuit is connected to the current sampling sub-circuit, and the second output terminal of the rectifier circuit is connected to the metal casing or the battery module.

4. The battery cluster according to any one of claims 1-3, characterized in that, The insulation detection circuit includes a switch sub-circuit, which is used to turn on when an insulation detection start signal is received.

5. The battery cluster according to claim 4, characterized in that, The insulation detection circuit also includes a control sub-circuit; The control sub-circuit is used to send the insulation detection start signal to the switch sub-circuit when the battery cluster is in a non-charging and non-discharging state.

6. The battery cluster according to claim 5, characterized in that, The first battery management circuit is also used to send the position of the first battery pack in the battery cluster to the battery control circuit.

7. An energy storage system, characterized in that, The energy storage system includes an energy storage converter and a battery cluster as described in any one of claims 1-6, wherein the battery cluster is connected to the energy storage converter.

8. An uninterruptible power supply system, characterized in that, The uninterruptible power supply system includes an AC / DC converter, a DC / AC converter, and a battery cluster as described in any one of claims 1-6, wherein the battery cluster is connected to the AC / DC converter and the DC / AC converter.

9. An electric vehicle, characterized in that, The electric vehicle includes an electric motor and a battery cluster as described in any one of claims 1-6, wherein the battery cluster is used to provide power to the electric motor.

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