Battery management system, battery system and electrical device

Abstract

The present application discloses a battery management system, a battery system and an electrical device. The battery management system includes: a first connector for connecting to a battery; the switching circuit includes: an output node coupled to a first voltage terminal; an input node configured to receive a voltage signal of the battery; a control node configured to be coupled to the first connector or configured to be coupled between the input node and the first connector; at least one resistor is connected in series on the connection path between the input node and the control node of the switching circuit; a first target circuit configured to be coupled between the output node of the switching circuit and the first voltage terminal; when the input pin and the output pin of the first connector are connected, the control node of the switching circuit receives a control signal, controls the conduction between the input node and the output node, so that the battery supplies power to the first target circuit through the switching circuit. According to the embodiments of the present application, the problem that the battery management system is prone to short-circuit failure can be solved.

Description

Technical Field

[0001] The present application relates to the technical field of battery management, and particularly to a battery management system, a battery system, and an electrical device. Background Art

[0002] A battery is a device that converts external energy into electrical energy and stores it inside to supply power to external devices when needed, and is increasingly widely used in fields such as consumer electronics, aerospace, energy storage, and new energy vehicles.

[0003] A battery management system (BMS) is a device for managing and protecting a battery. The battery management system includes a connector (such as a board-end connector), and the connector is used to connect the battery and the electrical device that needs to be powered.

[0004] The connector of the battery management system includes multiple functional pins. During testing or transportation, if a metal foreign object intrudes between the pins of the connector, it is easy to cause the battery management system to short-circuit and fail. Summary of the Invention

[0005] The present application provides a battery management system, a battery system, and an electrical device, which can solve the problem that the battery management system is prone to short-circuit failure.

[0006] In a first aspect, the present application provides a battery management system, including: a first connector for connecting to a battery; a switching circuit including an output node, an input node, and a control node, wherein the output node is coupled to a first voltage terminal; the input node is configured to be coupled to a first pole of the battery to receive a voltage signal of the battery; the control node is configured to be coupled to the first connector or configured to be coupled between the input node and the first connector to receive a control signal; at least one resistor is connected in series on the connection path between the input node and the control node of the switching circuit; a first target circuit is configured to be coupled between the output node of the switching circuit and the first voltage terminal; when the input pin and the output pin of the first connector are connected, the control node of the switching circuit receives a control signal, controls the conduction between the input node and the output node, so that the battery supplies power to the first target circuit through the switching circuit.

[0007] According to the battery management system provided by the embodiments of the present application, a switching circuit is provided. The switching circuit is connected between the battery and the first target circuit. When the input pin and the output pin of the first connector are connected, the switching circuit can be turned on in response to the voltage signal of the battery. The battery does not directly supply power to the first target circuit, but uses the voltage signal provided by the battery as an enabling signal to control the switching circuit to turn on. When the switching circuit is turned on, the battery supplies power to the first circuit, without affecting the normal operation of the first target circuit; and at least one resistor in the switching circuit is connected in series on the connection path between the input node and the control node. In this way, when the first pin and the second pin are short-circuited, the resistor can be used for current limiting, and problems such as battery thermal runaway can be improved.

[0008] In a possible implementation manner of the first aspect, the switching circuit includes a first switch, a second switch, a first resistor, and a second resistor;

[0009] The first end of the first resistor is connected to the input node, and the second end of the first resistor is connected to the first end of the second resistor;

[0010] The first end of the first switch is connected to the input node, the second end of the first switch is connected to the output node, and the control end of the first switch is connected to the second end of the first resistor;

[0011] The first end of the second switch is connected to the second end of the second resistor, the second end of the second switch is connected to the ground end, and the control end of the second switch is connected to the control node.

[0012] In the embodiments of the present application, the second switch and the first switch are provided, and the voltage signal of the battery is used as the enabling signal of the second switch; when the second switch is turned on, the first switch is turned on, and the battery can supply power to the first target circuit; when the second switch is turned off, the first switch is turned off, and the battery no longer supplies power to the first target circuit; using the voltage signal of the battery as the enabling signal of the switch in the switching circuit eliminates the need to set up an additional controller and can ensure the normal operation of the circuit.

[0013] In a possible implementation manner of the first aspect, the first switch and the second switch are voltage-controlled switches. Voltage-controlled switches have no requirements for the magnitude of the input current. Therefore, the resistors used for current limiting are subject to fewer constraints. For example, resistors with large resistance values and small power parameters can be selected. In this way, it is possible to avoid excessive current when the input pin and the output pin of the first connector are short-circuited, effectively improving problems such as battery over-discharge, circuit ablation, and battery thermal runaway, and without causing the problem of high material costs.

[0014] In a possible implementation manner of the first aspect, the input pin of the first connector is connected to the first pole of the battery, and the switching circuit further includes:

[0015] A third resistor, connected between the input pin of the first connector and the first pole of the battery;

[0016] A fourth resistor, connected between the control terminal of the second switch and the output pin of the first connector.

[0017] In the embodiment of the present application, when the input pin is connected to the first pole of the battery, the switching circuit further includes a third resistor connected to the input pin and a fourth resistor connected to the output pin. The third resistor and the fourth resistor serve as current-limiting resistors, which can prevent the current in the battery loop from being too large when the input pin and the output pin are short-circuited, thereby effectively improving problems such as over-discharge of the battery, circuit ablation, and thermal runaway of the battery; and the fourth resistor can be used for voltage division, thereby preventing the second switch from being damaged when the output pin is shorted to the power supply.

[0018] In a possible implementation manner of the first aspect, the second switch includes an NMOS transistor, and the switching circuit further includes:

[0019] A fifth resistor, the first end of the fifth resistor is connected to the control terminal of the second switch, and the second end of the fifth resistor is connected to the ground terminal.

[0020] In the embodiment of the present application, when the second switch is an NMOS transistor, a fifth switch is further provided and connected between the control terminal of the second switch and the ground terminal, so as to ensure that the state of the second switch can be accurately controlled.

[0021] In a possible implementation manner of the first aspect, the second switch includes an NPN transistor, and the switching circuit further includes a sixth resistor and a seventh resistor;

[0022] The sixth resistor is connected between the control terminal of the second switch and the output pin of the first connector;

[0023] The seventh resistor is connected between the control terminal of the second switch and the ground terminal.

[0024] In the embodiment of the present application, when the second switch is an NPN transistor, a sixth resistor and a seventh resistor are further provided, so as to ensure that the state of the second switch can be accurately controlled.

[0025] In a possible implementation manner of the first aspect, the second switch includes a PNP transistor, the output pin of the first connector is connected to the ground terminal, and the switching circuit further includes an eighth resistor and a ninth resistor;

[0026] The eighth resistor is connected between the control terminal of the second switch and the input pin of the first connector;

[0027] The ninth resistor is connected between the control terminal of the second switch and the second end of the second resistor.

[0028] In the embodiment of the present application, when the second switch is a PNP type triode, the output pin is connected to the ground terminal, and an eighth resistor and a ninth resistor are also provided, so as to ensure that the state of the second switch can be accurately controlled.

[0029] In a possible implementation manner of the first aspect, the first switch includes a PMOS type transistor.

[0030] In a possible implementation manner of the first aspect, the battery management system further includes:

[0031] A diode, which is connected in series on the connection path between the first pole of the battery and the first connector.

[0032] In the embodiment of the present application, the function of the diode is reverse protection, which can prevent the internal circuit and the battery from being damaged by voltage backflow when the output pin is short-circuited to a higher external voltage.

[0033] In a possible implementation manner of the first aspect, the battery management system further includes:

[0034] A second target circuit, which is connected to the first pole of the battery.

[0035] In the embodiment of the present application, the second target circuit is no longer connected to the battery through a switching circuit. In this way, when the battery supplies power to the second target circuit, it is no longer controlled by the switching circuit, that is, whether the switching circuit is turned on or off, the battery can supply power to the second target circuit.

[0036] In a possible implementation manner of the first aspect, the battery management system further includes:

[0037] A power conversion circuit, and the first target circuit and the second target circuit are connected to the first pole of the battery through the power conversion circuit.

[0038] In the embodiment of the present application, the first target circuit and the second target circuit can share a power conversion circuit, which can simplify the structure.

[0039] Based on the same inventive concept, in the second aspect, the embodiment of the present application provides a battery system, including the battery management system according to any one of the embodiments of the first aspect.

[0040] Based on the same inventive concept, in the third aspect, the embodiment of the present application provides an electrical device, including the battery system according to any one of the embodiments of the second aspect.

[0041] The above description is only an overview of the technical solution of the present application. In order to be able to understand the technical means of the present application more clearly, it can be implemented according to the content of the specification. And in order to make the above and other purposes, features and advantages of the present application more obvious and understandable, the specific embodiments of the present application are specifically given below. Description of the Drawings

[0042] The features, advantages, and technical effects of exemplary embodiments of the present application will be described below with reference to the accompanying drawings.

[0043] Figure 1 It is a schematic structural diagram of a battery management system in a comparative example;

[0044] Figure 2 It is a schematic structural diagram of a battery management system in another comparative example;

[0045] Figure 3 It is a schematic structural diagram of a battery management system according to an embodiment of the present application;

[0046] Figure 4 It is another schematic structural diagram of a battery management system according to an embodiment of the present application;

[0047] Figure 5 It is yet another schematic structural diagram of a battery management system according to an embodiment of the present application;

[0048] Figure 6 It is yet another schematic structural diagram of a battery management system according to an embodiment of the present application;

[0049] Figure 7 It is yet another schematic structural diagram of a battery management system according to an embodiment of the present application;

[0050] Figure 8 It is yet another schematic structural diagram of a battery management system according to an embodiment of the present application. Detailed implementation manners

[0051] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without making creative efforts shall fall within the scope of protection of the present application.

[0052] Unless otherwise defined, all technical and scientific terms used in the present application have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs; the terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application; the terms "including" and "having" and any variations thereof in the specification and claims of the present application and the above drawings are intended to cover non-exclusive inclusion. The terms "first", "second", etc. in the specification and claims of the present application or the above drawings are used to distinguish different objects and are not used to describe a specific order or primary-secondary relationship.

[0053] In the description of the present application, it should be noted that unless otherwise clearly specified and defined, the terms "install", "connect", "join", "attach", "couple" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0054] The battery management system includes a first connector (which can also be called a board-end connector), the first connector is connected to the battery, and the first connector is used to connect to an external second connector (which can also be called a wire-end connector). The battery supplies power to the load on the electrical device through the first connector and the second connector.

[0055] The inventors have found through research that during production testing or transportation, the second connector is not connected to the first connector. In this case, the pins of the first connector are exposed to the air. If a metal foreign object intrudes between the pins of the first connector, it will cause a short-circuit fault between the pins of the first connector. Once a short-circuit fault occurs between the pins of the first connector, when the external discharge current of the battery is relatively large, it will cause the battery to discharge quickly, leading to risks such as burning out the circuit board of the battery management system and thermal runaway of the battery.

[0056] As Figure 1 shown, the input pin 21 of the first connector is directly connected to the positive electrode of the battery, and the battery directly outputs voltage through the first connector without short-circuit protection measures. The first connector has multiple functional pins. During production testing or transportation, if a metal foreign object intrudes between the pins of the first connector, it is very easy to cause short-circuit failure. For example, the output voltage range of the battery is 9 - 16V. When the input pin 21 of the first connector is short-circuited to other functional pins, if the withstand voltage of the other short-circuited pin is greater than 16V, its internal circuit will not be damaged, but its internal circuit can be equivalent to a load, and the battery will continuously output electrical energy through the input pin 21, resulting in over-discharge of the battery and inability to be used normally. If the withstand voltage of the other short-circuited pin is less than 16V, its internal circuit will be damaged due to breakdown of the short-circuit voltage. The most serious situation is that the metal foreign object is directly short-circuited to the low-voltage ground, which is equivalent to directly short-circuiting the positive and negative electrodes of the battery, and the battery may experience thermal runaway.

[0057] To prevent the occurrence of the above problems, as Figure 2As shown, the inventor attempts to add a current-limiting resistor R' between the input pin 21 and the battery. When the input pin 21 is shorted to other functional pins, the current-limiting resistor R' will divide the voltage in the circuit. At this time, the voltage across the other shorted pin will be lower than 16V, achieving the protection purpose. When the input pin 21 is shorted to the low-voltage ground, the current-limiting resistor R1' plays a current-limiting role, protecting the traces on the circuit board from being ablated by large currents and protecting the battery from thermal runaway due to direct short-circuiting of the positive and negative electrodes.

[0058] The inventor continued to research and found that Figure 2 The solution of adding the current-limiting resistor R' as shown cannot prevent the problem of rapid over-discharge of the battery. Specifically, after the first connector and the second connector are connected, during normal use, the control switch is closed to connect the third pin 31 and the fourth pin 32 of the second connector. In this case, the loop to which the current-limiting resistor R' belongs is the power supply loop, and the current passing through is relatively large. Therefore, the current-limiting resistor R' needs to select a resistor with a large power parameter to ensure that when the input pin 21 is shorted to the ground, the resistor will not overheat and burn. At the same time, it also needs to be considered that the current-limiting resistor R' cannot be too large, and it can only be a resistor in the order of a few ohms. Otherwise, when used normally with the switch closed, the voltage output by the battery will be divided by the current-limiting resistor R', resulting in an under-voltage of the voltage output to the target circuit, and the greater the output current, the greater the influence of the voltage division of the current-limiting resistor R'. That is to say, when the resistance value of the current-limiting resistor R' is small, when a short-circuit fault occurs, the discharge current of the battery to the outside is very large, which will cause the battery to discharge rapidly. When the resistance value of the current-limiting resistor R' is large, it will cause a large voltage division during normal use, resulting in an under-voltage of the voltage output to the target circuit. Therefore, the selection parameters of the current-limiting resistor R' require a small resistance value and a large power, resulting in a high material cost. Therefore, this measure will introduce new problems such as selection and cost, and it is not the optimal solution and cannot fundamentally solve the problems caused by short circuits.

[0059] In view of the above technical problems, the embodiments of the present application provide a battery management system, a battery system, and an electrical device. The embodiments of the present application will be described below with reference to the accompanying drawings.

[0060] As Figure 3 and Figure 4 shown, the battery management system 20 includes a switch circuit 1, a first connector 2, and a first target circuit 41.

[0061] The first connector 2 is used to connect the battery 10. Exemplarily, the first connector 2 includes an input pin 21 and an output pin 22. Here, the input pin refers to the pin through which current flows into the first connector, and the output pin refers to the pin through which current flows out of the first connector.

[0062] Exemplarily, the input pin 21 is used to connect the third pin 31 of the second connector 3, and the output pin 22 is used to connect the fourth pin 32 of the second connector 3.

[0063] The switching circuit 1 includes an output node N4, an input node N1, and a control node N3.

[0064] The output node N4 is coupled to the first voltage terminal V1. The input node N1 is configured to be coupled to the first pole of the battery 10 to receive the voltage signal of the battery 10. The control node N3 is configured to be coupled to the first connector 2, or is configured to be coupled between the input node N1 and the first connector 2 to receive a control signal.

[0065] In the following embodiments, the first pole of the battery 10 is taken as the positive pole for description.

[0066] For example, as Figure 3 shown, the input pin 21 of the first connector 2 is connected to the first pole of the battery 10, and the output pin 22 of the first connector 2 is connected to the control node N3. It can be understood that in this case, when the input pin 21 and the output pin 22 are connected, the current path includes: output from the first pole of the battery 10, and transmitted through the first connector 2 to the control node N3, and the voltage signal output by the battery 10 serves as the control signal received by the control node N3.

[0067] Or, as Figure 4 shown, the input pin 21 of the first connector 2 is connected to the control node N3, and the output pin 22 of the first connector 2 is connected to the ground terminal GND. It can be understood that in this case, when the input pin 21 and the output pin 22 are connected, the current path includes: output from the first pole of the battery 10, and transmitted through the control node N3 to the input pin 21 of the first connector 2, and then transmitted through the output pin 22 to the ground terminal GND, and the voltage signal output by the battery 10 serves as the control signal received by the control node N3.

[0068] The switching circuit 1 further includes at least one resistor 11, and the at least one resistor 11 is connected in series on the connection path between the input node N1 and the control node N3.

[0069] The first target circuit 41 is configured to be coupled between the output node N4 of the switching circuit 1 and the first voltage terminal V1.

[0070] When the input pin 21 and the output pin 22 of the first connector 2 are connected, the control node N3 of the switching circuit 1 receives a control signal, controls the conduction between the input node N1 and the output node N4, so that the battery 10 supplies power to the first target circuit 41 through the switching circuit 1.

[0071] Exemplarily, the battery management system 20 includes a circuit board. The switch circuit 1, the first connector 2, and the first target circuit 41 can be disposed on the circuit board. The first connector 2 can be referred to as a board-end connector. For example, one end of the input pin 21 can be soldered on the circuit board, and the other end of the input pin 21 is used to connect to the third pin 31. Similarly, one end of the output pin 22 can be soldered on the circuit board, and the other end of the output pin 22 is used to connect to the fourth pin 32. During production testing or transportation, the first connector 2 and the second connector 3 are not connected. During normal use, the first connector 2 and the second connector 3 are connected, and the battery 10 powers the load through the first connector 2 and the second connector 3.

[0072] The second connector 3 can be referred to as a wire-end connector. For example, the connection assembly 30 includes the second connector 3 and the control switch 5. The control switch 5 is used to control whether the third pin 31 and the fourth pin 32 of the second connector 3 can be connected. For instance, when the control switch 5 is closed, the third pin 31 and the fourth pin 32 are connected; when the control switch 5 is open, the third pin 31 and the fourth pin 32 are disconnected. Exemplarily, the control switch 5 is a mechanical switch. For example, the mechanical switch is a push switch. The user can press the mechanical switch as needed. Press the push switch once when it is closed to make it open, and press the push switch once when it is open to make it closed.

[0073] Exemplarily, the first connector 2 is a connection socket soldered on the circuit board, and the second connector 3 is a connection plug of the connection assembly. They can be plugged into each other.

[0074] When the first connector 2 and the second connector 3 are connected and the third pin 31 and the fourth pin 32 are connected, the input pin 21 and the output pin 22 can be connected through the third pin 31 and the fourth pin 32.

[0075] For example, during production testing or transportation, if the input pin 21 and the output pin 22 are short-circuited, the input pin 21 and the output pin 22 will be conducted.

[0076] Exemplarily, when the first connector 2 and the second connector 3 are connected and the third pin 31 and the fourth pin 32 are connected, the input pin 21 and the output pin 22 will also be conducted.

[0077] It is understandable that when the input pin 21 and the output pin 22 are conducting, a path (connected path) is formed among the battery 10, the control node N3 of the switch circuit 1, and between the input pin 21 and the output pin 22. The voltage signal provided by the battery 10 can be transmitted to the control node N3 of the switch circuit 1, thereby controlling the switch in the switch circuit 1 to conduct. Since the first target circuit 41 is connected to the battery 10 through the switch circuit 1, when the switch circuit 1 is conducting, the battery 10 is connected to the first target circuit 41 through the switch circuit 1, enabling the battery 10 to supply power to the first target circuit 41. It can be seen that in the embodiment of the present application, the battery 10 does not directly supply power to the first target circuit 41, but uses the voltage signal provided by the battery 10 as an enabling signal to control the switch circuit 1 to conduct. When the switch circuit 1 is conducting, the battery supplies power to the first target circuit 41.

[0078] In addition, at least one resistor 11 in the switch circuit 1 is on the connected path that serially connects the input node N1 and the control node N3. Therefore, the resistor 11 can be used as a current-limiting resistor to limit the magnitude of the current on the connected path between the positive electrode of the battery 10 and the first connector 2.

[0079] Exemplarily, the switch (not shown in Figure 3 and Figure 4 controlled by the control node in the switch circuit 1) is a voltage-controlled device.

[0080] Since the switch controlled by the control node in the switch circuit 1 is a voltage-controlled device and has no requirement for the magnitude of the input current, the resistor 11 used for current limiting can be selected with a large resistance value and a small power parameter. In this way, it can avoid excessive current when the input pin 21 and the output pin 22 are short-circuited, effectively improving problems such as over-discharge of the battery, circuit ablation, and battery thermal runaway, and will not cause the problem of high material cost.

[0081] In summary, according to the battery management system provided by the embodiment of the present application, a switch circuit is provided. The switch circuit is connected between the battery and the first target circuit. When the input pin and the output pin of the first connector are connected, the switch circuit can conduct in response to the voltage signal of the battery. The battery does not directly supply power to the first target circuit, but uses the voltage signal provided by the battery as an enabling signal to control the switch circuit to conduct. When the switch circuit is conducting, the battery supplies power to the first circuit, without affecting the normal operation of the first target circuit; and at least one resistor in the switch circuit is serially connected on the connected path between the input node and the control node, that is to say, at least one resistor is serially connected on the connected path between the battery and the first connector. When the input pin and the output pin are short-circuited, this resistor can be used for current limiting.

[0082] In addition, the switch controlled by the control node in the switch circuit is a voltage-controlled switch, which has no requirement for the magnitude of the input current. Therefore, the resistor used for current limiting is subject to fewer constraints. For example, a resistor with a large resistance value and a small power parameter can be selected. In this way, it is possible to avoid excessive current when a short circuit occurs between the first pin and the second pin, thereby effectively improving problems such as over-discharge of the battery, circuit ablation, and thermal runaway of the battery, and it will not cause the problem of high material costs.

[0083] Exemplarily, when the input pin 21 and the output pin 22 are disconnected, the switch circuit 1 is disconnected, and the battery 10 cannot supply power to the first target circuit 41, and the first target circuit 41 is in a non-operating state.

[0084] For example, during production testing or transportation, at this time, the first target circuit 41 does not need to work. When there is no short circuit between the input pin 21 and the output pin 22, the input pin 21 and the output pin 22 are disconnected. At this time, the battery 10 does not need to supply power to the first target circuit 41. In this way, the power consumption of the battery can be saved.

[0085] Exemplarily, the switch circuit 1 may not include a resistor connected in series between the positive electrode of the battery 10 and the first target circuit 41, so as to avoid the problem of undervoltage of the power supply voltage of the first target circuit caused by the voltage division of the resistor in the presence of the resistor.

[0086] In some embodiments, as Figures 5 to 8 shown in any one of the attached drawings, the switch circuit 1 includes a first switch Q1, a second switch Q2, and a first resistor R1 and a second resistor R2.

[0087] The first end of the first resistor R1 is connected to the input node N1, and the second end of the first resistor R1 is connected to the first end of the second resistor R2; the first end of the first switch Q1 is connected to the input node N1, the second end of the first switch Q1 is connected to the output node N4, and the control end of the first switch Q1 is connected to the second end of the first resistor R1; the first end of the second switch Q2 is connected to the second end of the second resistor R2, the second end of the second switch Q2 is connected to the ground terminal GND, and the control end of the second switch Q2 is connected to the output pin 22.

[0088] Exemplarily, both the first switch Q1 and the second switch Q2 are voltage-controlled devices.

[0089] As an example, the input pin of the first connector is connected to the positive electrode of the battery. Specifically, as Figures 5 to 7As shown, the input pin 21 is connected to the positive electrode of the battery 10 at the input node N1. The first resistor R1 and the second resistor R2 are connected to the second node N2. The control terminal of the second switch Q2 and the output pin 22 are connected to the control node N3. When the input pin 21 and the output pin 22 are conducting, the voltage signal Vbat at the positive electrode of the battery 10 is transmitted to the control node N3 through the input pin 21 and the output pin 22, thereby controlling the second switch Q2 to conduct. After the second switch Q2 conducts, a conduction path is formed between the second node N2 and the ground terminal GND. The first resistor R1 and the second resistor R2 are in series for voltage division. The voltage division across the first resistor R1 is used to control the first switch Q1 to conduct, so that the battery 10 can supply power to the first target circuit 41 through the first switch Q1.

[0090] When the input pin 21 and the output pin 22 are disconnected, the voltage signal Vbat at the positive electrode of the battery 10 cannot be transmitted to the control node N3. The second switch Q2 is disconnected, and the first switch Q1 is also disconnected. The battery 10 no longer supplies power to the first target circuit 41, and the first target circuit 41 is in a non-operating state.

[0091] As another example, the output pin of the first connector is connected to the ground terminal. Specifically, as Figure 8 shown, when the input pin 21 and the output pin 22 are conducting, a conduction path is formed between the positive electrode of the battery 10 and the ground terminal GND. The voltage signal Vbat at the positive electrode of the battery 10 is transmitted to the control node N3 through the first resistor R1 and the second resistor R2, thereby controlling the second switch Q2 to conduct. After the second switch Q2 conducts, a conduction path is formed between the second node N2 and the ground terminal GND N2. The first resistor R1 and the second resistor R2 are in series for voltage division. The voltage division across the first resistor R1 is used to control the first switch Q1 to conduct, so that the battery 10 can supply power to the first target circuit 41 through the first switch Q1.

[0092] When the input pin 21 and the output pin 22 are disconnected, a conduction path is not formed between the positive electrode of the battery 10 and the ground terminal GND. The voltage at the control node N3 controls the second switch Q2 to disconnect, and the first switch Q1 is also disconnected. The battery 10 no longer supplies power to the first target circuit 41, and the first target circuit 41 is in a non-operating state.

[0093] In the embodiments of the present application, the second switch and the first switch are provided, and the voltage signal of the battery is used as the enabling signal of the second switch; when the second switch conducts, the first switch conducts, and the battery can supply power to the first target circuit; when the second switch disconnects, the first switch disconnects, and the battery no longer supplies power to the first target circuit; using the voltage signal of the battery as the enabling signal of the switch in the switch circuit eliminates the need to set up an additional controller and can ensure the normal operation of the circuit.

[0094] It can be understood that, as Figure 8As shown, when the output pin of the first connector is connected to the ground terminal, the first resistor R1 and the second resistor R2 can serve as the current-limiting resistors 11 connected in series on the connection path between the positive electrode of the battery 10 and the first connector 2, and the eighth resistor R8 and the ninth resistor R9 can also serve as the current-limiting resistors 11 connected in series on the connection path between the positive electrode of the battery 10 and the first connector 2.

[0095] When the input pin of the first connector is connected to the positive electrode of the battery, other resistors can be set as current-limiting resistors.

[0096] In some embodiments, as Figures 5 to 7 shown, the input pin of the first connector is connected to the first pole of the battery, and the switching circuit 1 further includes a third resistor R3 and a fourth resistor R4. The third resistor R3 is connected between the input pin 21 and the first pole of the battery 10. The fourth resistor R4 is connected between the control terminal of the second switch Q2 and the output pin 22.

[0097] The third resistor R3 and the fourth resistor R4 serve as the current-limiting resistors 11 connected in series on the connection path between the positive electrode of the battery 10 and the first connector 2. The voltage signal Vbat at the positive electrode of the battery 10 serves as an enabling signal and is transmitted to the control node N3 through the third resistor R3, the input pin 21, the output pin 22, and the fourth resistor R4. The third resistor R3 can be referred to as the current-limiting resistor on the input loop of the first connector, and the fourth resistor R4 can be referred to as the current-limiting resistor on the output loop of the first connector.

[0098] The second switch Q2 is a voltage-controlled device and has no requirement for the magnitude of the input current. As long as the voltage at the control node N3 is greater than the turn-on voltage of the second switch Q2, therefore, the third resistor R3 and the fourth resistor R4 can select resistors with large resistance values and small power parameters. Moreover, neither the third resistor R3 nor the fourth resistor R4 is on the power supply path from the battery to the first target circuit 41. Therefore, the voltage division of the third resistor R3 and the fourth resistor R4 does not affect the voltage output at the second terminal of the first switch Q1, and this voltage serves as the power supply for the first target circuit 41.

[0099] The larger the resistance value selected for the third resistor R3, the better the effect of protecting the battery from short circuit. For example, if the third resistor R3 selects a resistor with a resistance value of 1 MΩ, the short-circuit current can be limited to the microampere (uA) order of magnitude. Additionally, according to the power formula P = I 2*R, I = U / R. When the voltage is constant, the larger the resistance value, the more conducive it is to reducing the current value, and thus more conducive to reducing the power P. Therefore, a large resistance value can avoid the heating and ablation of the devices in the short - circuit loop, and can also prevent the battery from experiencing thermal runaway due to short - circuit. Moreover, when the first pin and the second pin are short - circuited, a large current - limiting resistance can make the external discharge current of the battery extremely small, effectively improving the problem of rapid over - discharge of the battery. The selection of the resistance value of the fourth resistor R4 is the same, and will not be elaborated here.

[0100] In addition, when the output pin 22 is short - circuited to an external power supply, the fourth resistor R4 can also divert the voltage to prevent the voltage at the control node N3 from being too high, thereby avoiding damage to the control terminal of the second switch Q2.

[0101] In the embodiments of the present application, when the input pin of the first connector is connected to the positive electrode of the battery, the switching circuit further includes a third resistor connected to the input pin of the first connector and a fourth resistor connected to the output pin of the first connector. The third resistor and the fourth resistor serve as current - limiting resistors, which can avoid too large a current in the loop where the battery is located when the input pin and the output pin of the first connector are short - circuited, thereby effectively improving problems such as battery over - discharge, circuit ablation, and battery thermal runaway; and the fourth resistor can be used for voltage division to avoid damage to the second switch.

[0102] The first switch Q1 and the second switch Q2 can be voltage - controlled devices.

[0103] In some embodiments, as Figures 5 to 8 shown in any of the accompanying drawings, the first switch Q1 includes a PMOS transistor (P - channel Metal Oxide Semiconductor FET).

[0104] It can be understood that the first voltage terminal V1 serves as a bias voltage terminal to provide a bias voltage VS. When VGS = VG - VS>0 is satisfied, the first switch Q1 is in the on state. Here, VGS represents the gate - source voltage difference of the first switch Q1, VG represents the gate voltage of the first switch Q1, and VS represents the source voltage of the first switch Q1.

[0105] Of course, in other examples, other types of switches can also be selected as the first switch Q1, as long as the first switch Q1 is on when the second switch Q2 is on and the first switch Q1 is off when the second switch Q2 is off.

[0106] The second switch can be selected as a metal - oxide field - effect semiconductor transistor or a triode.

[0107] In some embodiments, such as Figure 5 or Figure 6As shown, the second switch Q2 includes an NMOS transistor (N-channel Metal Oxide Semiconductor FET), and the switching circuit 1 further includes a fifth resistor R5. The first end of the fifth resistor R5 is connected to the control terminal of the second switch Q2, and the second end of the fifth resistor R5 is connected to the ground terminal GND. Among them, the fourth resistor R4, the fifth resistor R5, and the control terminal of the second switch Q2 are connected to the control node N3.

[0108] When the input pin 21 and the output pin 22 are conducting, the enable signal output by the battery 10 is transmitted from the input pin 21 to the output pin 22, and after being divided by the fourth resistor R4 and the fifth resistor R5, it can control the second switch Q2 to conduct. When the input pin 21 and the output pin 22 are disconnected, the fifth resistor R5 pulls down the potential of the control node N3 to the potential of the ground terminal GND, controlling the second switch Q2 to disconnect.

[0109] In the embodiment of the present application, when the second switch is an NMOS transistor, a fifth resistor is also provided between the control terminal of the second switch and the ground terminal, which can ensure that the state of the second switch can be accurately controlled.

[0110] Take Figure 5 as an example. When the first connector 2 and the second connector 3 are connected, for example, when the control switch 5 is not closed, the first target circuit 41 has no power supply requirement, and only requires that the first target circuit 41 can work normally after the control switch 5 is closed.

[0111] After the control switch 5 is closed, the voltage signal Vbat at the positive pole of the battery 10 serves as the enable signal, and the transmission path of the enable signal is as shown by the dotted line with an arrow in Figure 5 . The enable signal is output from the positive pole of the battery 10, transmitted through the third resistor R3 to the input pin 21 of the first connector 2, then transmitted to the third pin 31, then transmitted to the fourth pin 32, and then transmitted to the output pin 22. After being divided by the fourth resistor R4 and the fifth resistor R5, it controls the second switch Q2 of the NMOS transistor to conduct.

[0112] After the second switch Q2 conducts, the second resistor R2 is connected to the ground terminal GND, and the first resistor R1 and the second resistor R2 are connected in series to divide the voltage. The voltage divided on the first resistor R1 controls the first switch Q1 to conduct.

[0113] After the first switch Q1 conducts, the positive pole of the battery 10 outputs voltage through the first switch Q1. After the first switch Q1 conducts, the impedance is relatively small, and basically no voltage division occurs, and there is no other resistor for voltage division. Therefore, the voltage of the first voltage terminal V1 is approximately equal to Vbat, so that the power supply of the first target circuit 41 will not be undervoltaged.

[0114] Exemplarily, the first target circuit 41 requires low-voltage power supply, and the battery management system may further include a power conversion circuit 6 , which converts the first voltage terminal V1 into a voltage V2 output, and the voltage V2 serves as the power supply voltage of the first target circuit 41 .

[0115] When there is no voltage on the control node N3, the second switch Q2 is turned off, the first resistor R1 and the second resistor R2 cannot be connected to the ground terminal GND, the voltage difference across the first resistor R1 is zero, and the first switch Q1 is also turned off. At this time, the voltage of the first voltage terminal V1 is zero, the voltage V2 is also zero, and the first target circuit 41 does not work.

[0116] In other embodiments, Figure 7 As shown, the second switch Q2 may include an NPN transistor, and the switch circuit 1 further includes a sixth resistor R6 and a seventh resistor R7. The sixth resistor R6 is connected between the control terminal of the second switch Q3 and the output pin 22; the seventh resistor R7 is connected between the control terminal of the second switch Q2 and the ground terminal GND.

[0117] The sixth resistor R6 and the seventh resistor R7 may be input resistors of the transistor. The second switch Q2 of the NPN transistor can be turned on by selecting appropriate resistance values ​​of the resistors to ensure that the control terminal voltage of the second switch Q2 is greater than the input threshold.

[0118] For example, the voltage signal Vbat of the positive electrode of the battery 10 ranges from 9V to 16V, the sixth resistor R6 is 10KΩ, the seventh resistor R7 is 47KΩ, the withstand voltage of the control end of the second switch Q2 is 50V, the turn-on threshold voltage of the second switch Q2 is 0.7V, and the resistance value of the third resistor R3 and the fourth resistor R4 can be selected to be 51KΩ.

[0119] For example, Vbat=9V, when the control switch 5 is closed, the voltage at the control terminal of the second switch Q2 is the divided voltage on the seventh resistor R7, and the divided voltage on the seventh resistor R7 is (Vbat*R7) / (R3+R4+R6+R7).

[0120] That is, the divided voltage on the seventh resistor R7 is (9V*47KΩ) / (51KΩ+51KΩ+10KΩ+47KΩ)≈2.66V.

[0121] The divided voltage on the seventh resistor R7 is greater than 0.7V, and the second switch Q2 is turned on. If the input pin 21 is short-circuited, the selection of R3=10KΩ can control the discharge current of the battery to 9V / 51KΩ≈0.18mA, which can prevent the battery from discharging quickly. The power P on the third resistor R3=Vbat 2 / R7=9V / 51KΩ≈0.0016W, so the third resistor can be a regular 0603 package resistor (rated power is 0.1W), which is sufficient for use.

[0122] For another example, when Vbat = 16V and the control switch 5 is closed, the voltage at the control terminal of Q2 is the voltage divided by the R10 resistor, and the voltage at the control terminal of the second switch Q2 is the voltage divided by the seventh resistor R7. The voltage divided by the seventh resistor R7 is (16V * 47KΩ) / (51KΩ + 51KΩ + 10KΩ + 47KΩ) ≈ 4.72V.

[0123] The voltage divided by the seventh resistor R7 is greater than 0.7V, and the second switch Q2 conducts. If the input pin 21 is short - circuited, the selection of R3 = 10KΩ can control the discharge current of the battery to be 16V / 51KΩ ≈ 0.31mA, preventing the battery from discharging quickly. The power P on the third resistor R3 is P = Vbat 2 / R7 = 16V / 51KΩ ≈ 0.005W. In this way, the third resistor can select a conventional 0603 package resistor (rated power is 0.1W) and still meet the usage requirements.

[0124] It should be noted that the parameters of the devices in the above examples are only some examples and are not used to limit this application. The parameters of each device can be based on actual applications.

[0125] In the embodiment of this application, when the second switch is an NPN - type triode, the sixth resistor and the seventh resistor are also set, so as to ensure that the state of the second switch can be accurately controlled.

[0126] Figure 7 In the case where the first connector 2 and the second connector 3 are connected, for example, when the control switch 5 is not closed, the first target circuit 41 has no power supply requirement, and only requires that the first target circuit 41 can work normally after the control switch 5 is closed.

[0127] After the control switch 5 is closed, the voltage signal Vbat at the positive pole of the battery 10 is used as an enabling signal, and the transmission path of the enabling signal is as Figure 7 shown by the dotted line with an arrow in the figure. The enabling signal is output from the positive pole of the battery 10, transmitted through the third resistor R3 to the input pin 21 of the first connector 2, then transmitted to the third pin 31, then transmitted to the fourth pin 32, then transmitted to the output pin 22, and after being divided by the sixth resistor R6 and the seventh resistor R7, it controls the NPN - type transistor second switch Q2 to conduct.

[0128] After the second switch Q2 conducts, the second resistor R2 is connected to the ground terminal GND, and the first resistor R1 and the second resistor R2 are in series for voltage division. The voltage divided on the first resistor R1 controls the first switch Q1 to conduct.

[0129] After the first switch Q1 is turned on, the positive electrode of the battery 10 outputs a voltage through the first switch Q1. After the first switch Q1 is turned on, the impedance is relatively small, and basically no voltage division is caused, and there is no other resistance voltage division, so the voltage of the first voltage terminal V1 is approximately equal to Vbat, so that the power supply of the first target circuit 41 will not be undervoltage.

[0130] In some other embodiments, Figure 8 As shown, the second switch includes a PNP transistor, the input pin 21 is connected to the ground terminal GND, and the switch circuit 1 also includes an eighth resistor R8 and a ninth resistor R9; the eighth resistor R8 is connected between the control end of the second switch Q2 and the output pin 22; the ninth resistor R9 is connected between the control end of the second switch Q2 and the second end of the second resistor R2.

[0131] The eighth resistor R8 and the ninth resistor R9 may be input resistors of the transistor. The second switch Q2 of the PNP transistor can be turned on by selecting appropriate resistance values ​​of the resistors to ensure that the control terminal voltage of the second switch Q2 is greater than the input threshold.

[0132] Figure 8 In the case where the first connector 2 and the second connector 3 are connected, for example, after the control switch 5 is closed, the output pin 22 is connected to the ground terminal GND, and the positive electrode of the battery 10 forms a conduction loop through the first resistor R1, the second resistor R2, the ninth resistor R9, the eighth resistor R8, the output pin 22, the fourth pin 32, the third pin 31, the input pin 21 and the ground terminal GND, and the voltage signal Vbat of the positive electrode of the battery 10 is used as the enable signal. The transmission path of the enable signal is as follows: Figure 8 As shown by the dotted line with an arrow in the middle, the voltage division of the ninth resistor R9 controls the second switch Q2 to be turned on.

[0133] After the second switch Q2 is turned on, the second resistor R2 is connected to the ground terminal GND, the first resistor R1 and the second resistor R2 are connected in series to divide the voltage, and the voltage divided on the first resistor R1 controls the first switch Q1 to turn on.

[0134] After the first switch Q1 is turned on, the positive electrode of the battery 10 outputs a voltage through the first switch Q1. After the first switch Q1 is turned on, the impedance is relatively small, and basically no voltage division is caused, and there is no other resistance voltage division, so the voltage of the first voltage terminal V1 is approximately equal to Vbat, so that the power supply of the first target circuit 41 will not be undervoltage.

[0135] It is understandable that in this design method, the first resistor R1, the second resistor R2, the eighth resistor R8, and the ninth resistor R9 are connected in series on the connection path between the positive electrode of the battery and the output pin 22. Therefore, the first resistor R1, the second resistor R2, the eighth resistor R8, and the ninth resistor R9 serve as the current-limiting resistor 11. By adjusting the resistance value of at least one of the first resistor R1, the second resistor R2, the eighth resistor R8, and the ninth resistor R9, the magnitude of the short-circuit current can be controlled to prevent rapid over-discharge and short-circuit failure of the battery.

[0136] In the embodiment of the present application, when the second switch is a PNP-type triode, the output pin of the first connector is connected to the ground terminal, and an eighth resistor and a ninth resistor are also provided, which can ensure accurate control of the state of the second switch.

[0137] In some embodiments, as Figure 8 shown, the battery management system further includes a diode D1, and the diode D1 is connected in series on the connection path between the first pole of the battery 10 and the first connector 2. For example, the positive electrode of the diode D1 is connected to the eighth resistor R8, and the negative electrode of the diode D1 is connected to the input pin 21.

[0138] In the embodiment of the present application, the function of the diode is reverse protection, which can prevent voltage backflow from damaging the internal circuit and the battery when the input pin 21 is short-circuited to an external higher voltage.

[0139] In some application scenarios, it is required that when the control switch 5 is not closed, some target circuits need to be in the working state, so it is necessary to supply power to these target circuits that need to work.

[0140] In some embodiments, as Figure 6 shown, the battery management system further includes a second target circuit 42, and the second target circuit 42 is connected to the first pole of the battery 10.

[0141] The second target circuit 42 is no longer connected to the battery 10 through the switch circuit 1. When the battery 10 supplies power to the second target circuit 42, it is no longer controlled by the switch circuit 1, that is, whether the switch circuit 1 is turned on or off, the battery 10 can supply power to the second target circuit 42.

[0142] In some embodiments, as Figure 6 shown, when both the first target circuit 41 and the second target circuit 42 require low-voltage power supply, the battery management system may further include a power conversion circuit 6, and the first target circuit 41 and the second target circuit 42 are connected to the first pole of the battery 10 through the power conversion circuit 6. In the embodiment of the present application, the first target circuit and the second target circuit can share a power conversion circuit, which can simplify the structure.

[0143] Exemplarily, the voltage signal Vbat provided by the positive electrode of the battery 10 is converted by the power conversion circuit 6, and the low-voltage constant power voltage V2 is output. The voltage V2 can supply power to the second target circuit 42 directly without passing through the first switch Q1. The input end of the first switch Q1 is connected to the voltage V2. When the first switch Q1 is turned on, the output end of the first switch Q1 outputs a voltage to the first target circuit 41. When the first switch Q1 is turned on, ignoring the voltage drop of the first switch Q1, the voltage of the first voltage terminal V1 is equal to the voltage V2.

[0144] When the input pin 21 is connected to the output end of the power conversion circuit 6, the voltage of the battery is converted by the power conversion circuit 6 to output the voltage V2. The enable signal of the switch circuit is provided by the voltage V2. The enable signal is transmitted to the input pin 21 through the third resistor R3, and then transmitted to the third pin 31. After the control switch 5 controls the short circuit of the third pin 31 and the fourth pin 32, the enable signal is transmitted to the output pin 22 through the fourth pin 32, and then through the voltage division of the fourth resistor R4 and the fifth resistor R5, the second switch Q2 is controlled to conduct, and then the series circuit of the first resistor R1 and the second resistor R2 is turned on. The voltage division of the first resistor R1 controls the first switch Q1 to conduct, and the voltage output by the first switch Q1 supplies power to the first target circuit 41.

[0145] When the control switch 5 is turned off, there is no enable signal input to the switch circuit 1, and the voltage V2 is zero. At this time, the first target circuit 41 does not work, while the power supply of the second target circuit 42 comes from the low-voltage constant power voltage V2, and the second target circuit 42 can work normally to meet the functional requirements.

[0146] It should be noted that although only the second target circuit is shown in Figure 6 the second target circuit can also be set in the circuit architectures of Figure 5 and Figure 7 and Figure 8 .

[0147] Based on the same inventive concept, the embodiment of the present application also provides a battery system, including a battery and the battery management system in any of the above embodiments. It can be understood that the battery system has the beneficial effects of the battery management system provided by the embodiment of the present application. For specific details, reference can be made to the specific descriptions of the battery management system in the above embodiments, and details will not be repeated in this embodiment.

[0148] Based on the same inventive concept, the present application also provides an electrical device. The electrical device includes a battery system, and the battery system includes the battery management system in any of the above embodiments. It can be understood that the electrical device has the beneficial effects of the battery management system provided by the embodiment of the present application. For specific details, reference can be made to the specific descriptions of the battery management system in the above embodiments, and details will not be repeated in this embodiment.

[0149] It should be noted that in the above embodiments, the form of the resistor is a single resistor. In other embodiments, the resistor can also be an integration of series, parallel or series-parallel resistors. Additionally, in the above embodiments, the form of the capacitor is a single capacitor. In other embodiments, the capacitor can also be an integration of series, parallel or series-parallel capacitors. The specific parameters of each device can be set according to actual requirements, and the present application does not limit this.

[0150] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0151] Although the present application has been described with reference to the preferred embodiments, various improvements can be made to it and components therein can be replaced with equivalents without departing from the scope of the present application. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery management system, characterized in that: include: A first connector, used to connect a battery, the battery is connected to an external second connector through the first connector, and the second connector is used to supply power to a load on the electrical device; A switch circuit includes an output node, an input node, and a control node, wherein: The output node is coupled to a first voltage terminal; The input node is configured to be coupled to a first electrode of the battery to receive a voltage signal of the battery; The control node is configured to be coupled to an output pin of the first connector, and an input pin of the first connector is coupled to the input node, or is configured to be coupled between the input node and an input pin of the first connector, and an output pin of the first connector is coupled to a ground terminal, so as to receive a control signal; At least one resistor is connected in series on a communication path between the input node and the control node of the switch circuit; A first target circuit is configured to be coupled between an output node of the switch circuit and the first voltage terminal; When the input pin and the output pin of the first connector are connected, the control node of the switch circuit receives the control signal and controls the conduction between the input node and the output node, so that the battery supplies power to the first target circuit through the switch circuit.

2. The battery management system according to claim 1, characterized in that: The switch circuit includes a first switch, a second switch, a first resistor and a second resistor; A first end of the first resistor is connected to the input node, and a second end of the first resistor is connected to a first end of the second resistor; A first end of the first switch is connected to the input node, a second end of the first switch is connected to the output node, and a control end of the first switch is connected to the second end of the first resistor; The first end of the second switch is connected to the second end of the second resistor, the second end of the second switch is connected to the ground, and the control end of the second switch is connected to the control node.

3. The battery management system according to claim 2, characterized in that: The first switch and the second switch are voltage-controlled devices.

4. The battery management system according to claim 2 or 3, characterized in that: The input pin of the first connector is connected to the first pole of the battery, and the switch circuit further includes: a third resistor connected between the input pin and the first electrode of the battery; A fourth resistor is connected between the control end of the second switch and the output pin of the first connector.

5. The battery management system according to claim 4, characterized in that: The second switch includes an NMOS transistor, and the switch circuit further includes: A fifth resistor, wherein a first end of the fifth resistor is connected to the control end of the second switch, and a second end of the fifth resistor is connected to the ground end.

6. The battery management system according to claim 2 or 3, characterized in that: The second switch includes an NPN transistor, and the switch circuit also includes a sixth resistor and a seventh resistor; The sixth resistor is connected between the control end of the second switch and the output pin of the first connector; The seventh resistor is connected between the control terminal of the second switch and the ground terminal.

7. The battery management system according to claim 2 or 3, characterized in that: The second switch includes a PNP transistor, the output pin of the first connector is connected to the ground terminal, and the switch circuit also includes an eighth resistor and a ninth resistor; The eighth resistor is connected between the control end of the second switch and the input pin of the first connector; The ninth resistor is connected between the control end of the second switch and the second end of the second resistor.

8. The battery management system according to claim 2 or 3, characterized in that: The first switch includes a PMOS transistor.

9. The battery management system according to any one of claims 1 to 3, characterized in that: The battery management system further comprises: A diode is connected in series on a communication path between the first electrode of the battery and the first connector.

10. The battery management system according to any one of claims 1 to 3, characterized in that: The battery management system further comprises: The second target circuit is connected to the first electrode of the battery.

11. The battery management system according to claim 10, characterized in that: The battery management system further comprises: A power conversion circuit, wherein the first target circuit and the second target circuit are connected to a first pole of the battery through the power conversion circuit.

12. A battery system, characterized in that: The invention comprises a battery and a battery management system according to any one of claims 1 to 11.

13. An electrical device, characterized in that: Comprising the battery system as claimed in claim 12.

Images