Charging and discharging circuits, battery management system and battery system

Abstract

This application provides a charging / discharging circuit, a battery management system, and a battery system, belonging to the field of battery technology. The charging / discharging circuit includes: a detection circuit for detecting the detection voltage of a voltage detection node when the charging / discharging circuit is connected to an external device; the detection circuit includes: a voltage detection node for connecting to the external device, the detection voltage of which is used to determine the type of the external device; a first voltage terminal for receiving a first supply voltage, which is applied to the first voltage terminal based on the state of the battery management system; a first switch connected between the first voltage terminal and the voltage detection node for switching the connection relationship between the first voltage terminal and the voltage detection node; and a first detection resistor connected between the first voltage terminal and the voltage detection node and connected in series with the first switch. This circuit is compatible with various external devices, effectively improving compatibility.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a charging and discharging circuit, a battery management system, and a battery system. Background Technology

[0002] Energy conservation and emission reduction are key to sustainable social development. Rechargeable batteries, with their ability to store and release energy as needed, are widely used in various electrical devices and energy storage systems, and are an important component in promoting energy transition and sustainable development. For the new energy industry, battery technology is a crucial factor in its development.

[0003] Currently, rechargeable batteries need to be compatible with different types of charging and electrical devices, which may have different electrical performance parameters. During the charging and discharging process when the battery is connected to an external device, the relevant electrical performance needs to be tested. Furthermore, with the increasing diversity of external devices, the compatibility requirements for the battery charging and discharging process also become more stringent. Utility Model Content

[0004] This application aims to at least address the technical problem of poor compatibility in battery detection processes in the prior art. Therefore, one objective of this application is to provide a charging / discharging circuit that is compatible with charging / discharging detection functions across different external devices.

[0005] An embodiment of the first aspect of this application provides a charging and discharging circuit disposed in a battery system. The charging and discharging circuit includes: a detection circuit for detecting the detection voltage of a voltage detection node when the charging and discharging circuit is connected to an external device; the detection circuit includes: a voltage detection node for connecting to the external device, the detection voltage of the voltage detection node being used to determine the type of the external device; a first voltage terminal for receiving a first supply voltage, the first supply voltage being applied to the first voltage terminal based on the state of the battery management system; a first switch connected between the first voltage terminal and the voltage detection node for switching the connection relationship between the first voltage terminal and the voltage detection node; and a first detection resistor connected between the first voltage terminal and the voltage detection node and connected in series with the first switch.

[0006] In the technical solution of this application embodiment, by reasonably designing the detection circuit in the battery system, a good detection effect can be achieved for different types of external devices during the charging and discharging process of the battery system connected to external devices. It can be compatible with various external devices and effectively improve the compatibility and adaptability of the battery system.

[0007] In some embodiments, a first supply voltage is applied to the first voltage terminal when the battery management system is woken up. Applying the first supply voltage to the first voltage terminal only after the battery management system is woken up enables the normal wake-up function of the battery management system while being compatible with charge and discharge detection of different devices, reducing the risk that the battery management system cannot be woken up properly when connected to external devices.

[0008] In some embodiments, the first switch is used to connect the first voltage terminal to the voltage detection node when the battery management system is woken up. By reasonably controlling the on-time of the first switch, the reliability of the detection process can be improved, while the normal wake-up function of the battery management system can be realized.

[0009] In some embodiments, the resistance value of the first sensing resistor is greater than or equal to 900 ohms and less than or equal to 1100 ohms. Setting the resistance value of the first sensing resistor within a suitable range allows it to be compatible with external devices with different electrical performance parameters and accurately identify the type of external device.

[0010] In some embodiments, the detection circuit further includes a first filter circuit connected between the voltage detection node and the power supply ground, used to filter interference signals in the detection circuit. Including the first filter circuit in the detection circuit can suppress interference signals in the circuit and improve the accuracy of the detection results.

[0011] In some embodiments, the first filtering circuit includes a first filtering capacitor connected between the voltage sensing node and the power supply ground. Using a capacitor for filtering can simplify circuit design while achieving better filtering performance.

[0012] In some embodiments, the first filtering circuit includes: a first filtering resistor, a first terminal of which is connected to a voltage detection node; and a second filtering capacitor connected between a second terminal of the first filtering resistor and a power supply ground. Using a resistor and a capacitor to form the filtering circuit can improve the suppression effect on interference signals.

[0013] In some embodiments, the detection circuit further includes a protection circuit connected between the voltage detection node and the power supply ground, for providing voltage protection to the detection circuit. Using a protection circuit can effectively suppress large transient voltages in the circuit and reduce the risk of circuit damage.

[0014] In some embodiments, the protection circuit includes a transient suppression diode. Using a transient suppression diode simplifies circuit design while achieving good voltage protection.

[0015] In some embodiments, the charging / discharging circuit further includes a wake-up circuit connected to the detection circuit via a voltage detection node. The wake-up circuit is used to generate a wake-up signal in response to the charging / discharging circuit being connected to an external device. The wake-up signal is used to wake up the battery management system. By using the detection circuit and the wake-up circuit in conjunction, the battery management system can be woken up promptly when an external device is connected to the battery system, thereby enabling the corresponding functions.

[0016] In some embodiments, the wake-up circuit includes: a second voltage terminal for receiving a second supply voltage; a third voltage terminal for receiving a first supply voltage, wherein the first supply voltage is applied to the third voltage terminal when the battery management system is woken up; a fourth voltage terminal for receiving the second supply voltage; a plurality of sensing resistors for dividing the second supply voltage and / or the first supply voltage; and a plurality of switches for switching the connection relationship between the plurality of sensing resistors. A well-designed wake-up circuit can achieve the normal wake-up function of the battery management system and improve the reliability of the wake-up process.

[0017] In some embodiments, the plurality of switches includes a second switch connected to a voltage detection node, a fourth voltage terminal, and a power ground, for disconnecting when the charging / discharging circuit is not connected to an external device and turning on when the charging / discharging circuit is connected to an external device. By setting the second switch to be on and off, a wake-up function of the battery management system can be implemented when an external device is connected to the battery system.

[0018] In some embodiments, the plurality of switches further includes a third switch connected to the voltage detection node, the second switch, and the third voltage terminal, for conducting when the charging / discharging circuit is not connected to an external device and deactivating when the battery management system is woken up. By setting the conduction and deactivation of the third switch, the stability and reliability of the charging / discharging circuit can be improved while achieving normal wake-up of the battery management system.

[0019] In some embodiments, the plurality of switches further includes a fourth switch connected to the second switch, power ground, third voltage terminal, and the fourth switch, for disconnecting when the charging / discharging circuit is not connected to an external device and turning on when the battery management system is woken up. By setting the fourth switch to be on and off, the impact on other functions of the battery system can be reduced while achieving normal wake-up of the battery management system, thereby improving the reliability of the battery system.

[0020] In some embodiments, the plurality of sensing resistors includes: a second sensing resistor connected to a third voltage terminal and a third switch; a third sensing resistor connected to a second voltage terminal, a third switch, and a second switch; a fourth sensing resistor connected to the third sensing resistor, the third switch, and the fourth switch; a fifth sensing resistor connected to the second sensing resistor, the fourth sensing resistor, and power ground; a sixth sensing resistor connected to the fourth voltage terminal and the second switch; and a seventh sensing resistor connected to the second switch and power ground. By setting the positions and connections of each sensing resistor, accurate control of each switch can be achieved through voltage division, making the wake-up process more reliable and precise.

[0021] In some embodiments, the resistance of the second sensing resistor is greater than or equal to 50 ohms and less than or equal to 150 ohms; the resistance of the third sensing resistor is greater than or equal to 4.5 kΩ and less than or equal to 5.5 kΩ; the resistance of the fourth sensing resistor is greater than or equal to 0.9 MΩ and less than or equal to 1.1 MΩ; the resistance of the fifth sensing resistor is greater than or equal to 9.5 kΩ and less than or equal to 10.5 kΩ; the resistance of the sixth sensing resistor is greater than or equal to 14 kΩ and less than or equal to 16 kΩ; and the resistance of the seventh sensing resistor is greater than or equal to 99 kΩ and less than or equal to 101 kΩ. By setting the resistance values ​​of each sensing resistor, accurate control of each switch can be achieved through voltage division, making the wake-up process more reliable and precise.

[0022] In some embodiments, the plurality of sensing resistors further includes at least one of the following: an eighth sensing resistor connected to the voltage sensing node and the third switch; and a ninth sensing resistor connected to the second switch and the third switch. Including a current-limiting resistor in the circuit can reduce the risk of circuit damage due to excessive current and improve reliability.

[0023] In some embodiments, the resistance of the eighth sensing resistor is greater than or equal to 4.9 kΩ and less than or equal to 5.5 kΩ, and the resistance of the ninth sensing resistor is greater than or equal to 9.5 kΩ and less than or equal to 10.5 kΩ. Properly setting the current-limiting resistor can improve the reliability and stability of the circuit.

[0024] In some embodiments, the wake-up circuit further includes: a fifth voltage terminal for receiving a second supply voltage; and a sixth voltage terminal for receiving the second supply voltage. Increasing the voltage terminal for receiving the supply voltage can further improve the accuracy of the wake-up function.

[0025] In some embodiments, the plurality of switches further includes: a fifth switch, connected to a fifth voltage terminal and power ground, for disconnecting when the charging / discharging circuit is not connected to an external device and for turning on when the charging / discharging circuit is connected to an external device; and a sixth switch, connected to a sixth voltage terminal and power ground, for disconnecting when the charging / discharging circuit is not connected to an external device and for turning on when the charging / discharging circuit is connected to an external device. By adding the corresponding switches, an edge wake-up function can be implemented, while also enabling the battery management system to enter sleep mode when the battery system is connected to an external device.

[0026] In some embodiments, the wake-up circuit further includes a loop capacitor connected to the fifth voltage terminal and the sixth switch. By providing a loop capacitor, the reliability of the edge wake-up function can be improved.

[0027] In some embodiments, the plurality of sensing resistors further includes: a tenth sensing resistor connected to the sixth voltage terminal, the sixth switch, and the loop capacitor; an eleventh sensing resistor connected to the sixth switch and power ground; and a twelfth sensing resistor connected to the fifth voltage terminal and the fifth switch. By setting the positions and connections of each sensing resistor, accurate control of each switch can be achieved through voltage division, making the edge wake-up process more reliable and precise.

[0028] In some embodiments, the wake-up circuit further includes a second filter circuit connected between the second switch and the power ground, used to filter interference signals in the wake-up circuit. By including the second filter circuit in the detection circuit, interference signals in the circuit can be suppressed, improving the accuracy of the detection results.

[0029] In some embodiments, the second filtering circuit includes: a second filtering resistor, a first terminal of which is connected to a second switch; and a third filtering capacitor connected between a second terminal of the second filtering resistor and a power supply ground. Using a resistor and a capacitor to form the filtering circuit can improve the suppression effect on interference signals.

[0030] An embodiment of the second aspect of this application provides a battery management system that includes the charging and discharging circuit described in the above embodiments.

[0031] An embodiment of the third aspect of this application provides a battery system that includes the battery management system described in the above embodiments.

[0032] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0033] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the various drawings denote the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments disclosed in this application and should not be construed as limiting the scope of this application.

[0034] Figure 1 This is a schematic diagram of the vehicle structure according to some embodiments of this application;

[0035] Figure 2 This is a schematic diagram of the charging and discharging circuits of some embodiments of this application;

[0036] Figure 3 This is a schematic diagram of a charging and discharging circuit including a first filter circuit, according to some embodiments of this application;

[0037] Figure 4 This is a schematic diagram of a charging and discharging circuit including a wake-up circuit according to some embodiments of this application;

[0038] Figure 5 This is a schematic diagram of another charging and discharging circuit including a wake-up circuit, according to some embodiments of this application.

[0039] Explanation of reference numerals in the attached figures:

[0040] 1000 vehicles;

[0041] Battery system 100, vehicle controller 200, motor 300;

[0042] Charging and discharging circuit 10, detection circuit 11, wake-up circuit 12;

[0043] Voltage detection node A, first voltage terminal P1, first switch Q1, first detection resistor R1, equivalent resistance Rin, first filter capacitor C1, first filter resistor R2, second filter capacitor C2, transient suppression diode DZ1, second voltage terminal P2, third voltage terminal P3, fourth voltage terminal P4, second switch Q4, third switch Q2, fourth switch Q3, second detection resistor R4, third detection resistor R5, fourth detection resistor R7, fifth detection resistor R8, sixth detection resistor R9, seventh detection resistor R10, eighth detection resistor R3, ninth detection resistor R6, fifth voltage terminal P5, sixth voltage terminal P6, fifth switch Q5, sixth switch Q6, loop capacitor C4, tenth detection resistor R13, eleventh detection resistor R14, twelfth detection resistor R12, second filter resistor R11, third filter capacitor C3, first supply voltage U1, second supply voltage U2, power ground GND. Detailed Implementation

[0044] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0046] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0047] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0048] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0049] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0050] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0051] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0052] Currently, the application of rechargeable batteries is becoming increasingly widespread, judging from market trends. They are not only used in energy storage systems for hydropower, thermal power, wind power, and solar power plants, but also extensively in various electronic devices, such as electric bicycles, electric motorcycles, and electric vehicles, as well as in military equipment and aerospace. As the application areas of rechargeable batteries continue to expand, the market demand is also constantly increasing.

[0053] Currently, rechargeable batteries need to be compatible with different types of charging and electrical devices, which may have different electrical performance parameters. For example, regarding Chinese national standards and European standards, when the charging gun is connected to the battery system through interfaces such as AC_CC and DC_CC2, the equivalent resistance of the external devices differs between the two standards. For instance, in the Chinese standard scenario, there may be different cases such as: an equivalent resistance of 100 ohms (Ω) for a charging current of 63 amps (A), 220 Ω for a charging current of 32A, 680 Ω for a charging current of 32A, and 1500 Ω for a charging current of 16A. In the European standard scenario, such as V2L (Vehicle to Load), there may be different cases such as: an equivalent resistance of 470 Ω for a discharging current of 63A, 1000 Ω for a discharging current of 32A, 2000 Ω for a discharging current of 16A, and 2700 Ω for a discharging current of 10A. When external devices with different equivalent resistances are connected to the battery system for charging or discharging, the overlapping voltage ranges result in poor compatibility for voltage detection. This makes it difficult to accurately identify the equivalent resistance of the external devices based on the detection results, and consequently, to accurately determine the type of external device. Therefore, higher requirements are placed on the compatibility of the battery charging and discharging process.

[0054] To improve the compatibility of the detection process during charging and discharging, the detection circuit in the charging and discharging circuit can be reasonably set up. This way, when different external devices are connected to the battery system, different voltage detection results can be obtained for different equivalent resistances. Thus, the equivalent resistance of the external device can be accurately identified based on the detection voltage, and the type of external device can be further accurately determined.

[0055] Using such a charging and discharging circuit in a battery system can achieve good detection results for different types of external devices, and is compatible with various external devices, effectively improving the compatibility and adaptability of the battery system.

[0056] The battery cells disclosed in this application can be used, but are not limited to, in electrical devices or energy storage devices such as vehicles, ships, or aircraft. A power system comprising the battery cells and batteries disclosed in this application can be used to construct such an electrical device or energy storage device. This facilitates better testing results for different types of external devices and improves the compatibility and adaptability of the battery system.

[0057] This application provides an electrical device that uses a battery as a power source. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0058] This application also provides an energy storage device that uses a battery as a power source. The energy storage device can be, but is not limited to, an energy storage container, an energy storage cabinet, an energy storage power station, an energy storage battery pack, or a portable energy storage system.

[0059] For ease of explanation, the following embodiments will be described using a vehicle 1000 as an example of an electrical device according to an embodiment of this application.

[0060] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle provided in some embodiments of this application. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery system 100 is installed inside the vehicle 1000, and the battery system 100 can be located at the bottom, front, or rear of the vehicle 1000. The battery system 100 can be used to power the vehicle 1000; for example, the battery system 100 can serve as the operating power source for the vehicle 1000. The vehicle 1000 may also include a vehicle controller 200 and a motor 300. The vehicle controller 200 is used to control the battery system 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle 1000 during starting, navigation, and driving.

[0061] In some embodiments of this application, the battery system 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0062] This application provides a charging and discharging circuit disposed in a battery system. (See reference...) Figure 2 The charging / discharging circuit 10 includes a detection circuit 11. The detection circuit 11 is used to detect the detection voltage at voltage detection node A when the charging / discharging circuit 10 is connected to an external device. The detection circuit 11 includes voltage detection node A, a first voltage terminal P1, a first switch Q1, and a first detection resistor R1.

[0063] Voltage sensing node A is used to connect to external devices. The voltage sensed by voltage sensing node A is used to determine the type of external device.

[0064] The first voltage terminal P1 is used to receive the first supply voltage U1. The first supply voltage U1 is applied to the first voltage terminal P1 based on the state of the battery management system (not shown).

[0065] The first switch Q1 is connected between the first voltage terminal P1 and the voltage detection node A, and is used to switch the connection relationship between the first voltage terminal P1 and the voltage detection node A.

[0066] The first sensing resistor R1 is connected between the first voltage terminal P1 and the voltage sensing node A, and is connected in series with the first switch Q1.

[0067] In embodiments of this application, external devices may include charging devices and electrical appliances, such as charging piles and electrical loads. These external devices can be connected to the battery system via DC interfaces, AC interfaces, etc. For example, in Chinese standard charging, a charging gun can charge the battery system by inserting it into a charging interface; in European standard V2L discharging, the battery system can also discharge to external electrical loads via a discharging interface. Figure 2 As shown, the equivalent resistance of external devices such as charging equipment or electrical appliances outside the battery system is represented by Rin. When the external device is connected to the battery system, the equivalent resistance Rin is also connected to the charging and discharging circuit 10.

[0068] The first supply voltage U1 is not normally applied to the first voltage terminal P1, but is applied according to the state of the battery management system. The battery management system (BMS) can perform functions such as control and management of the battery system. As the state of the battery management system changes, the voltage at the first voltage terminal P1 also changes accordingly. The first switch Q1 can turn the connection between the first voltage terminal P1 and the voltage detection node A on or off.

[0069] When the equivalent resistance Rin is connected, the first supply voltage U1 is applied to the first voltage terminal P1, and the first switch Q1 is turned on, the equivalent resistance Rin will be divided by the first detection resistance R1. By detecting the voltage at the detection voltage detection node A, the detection voltage corresponding to different equivalent resistances Rin can be determined, thereby determining the type of external device.

[0070] exist Figure 2 In the example shown, the detected voltage U at voltage detection node A can be represented as follows:

[0071] U = U1 × Rin / (R1 + Rin).

[0072] In one example, the detection voltage U is expressed in millivolts (mV), and the detection voltage can be represented as U = (U1 × Rin / (R1 + Rin)) × 1000mV.

[0073] As mentioned above, different external devices may have different equivalent resistances Rin. For example, under the Chinese standard, a charging current of 63A corresponds to an equivalent resistance of 100Ω, 32A to 220Ω, 32A to 680Ω, and 16A to 1500Ω. Under the European standard, a discharging current of 63A corresponds to an equivalent resistance of 470Ω, 32A to 1000Ω, 16A to 2000Ω, and 10A to 2700Ω. Therefore, considering calculation errors, the detected voltage U will fall within a specific voltage range for different equivalent resistances. Through proper design, the voltage ranges corresponding to different equivalent resistances can be made non-overlapping. This allows the equivalent resistance to be determined based on the detected voltage range, thus identifying the type of external device.

[0074] By rationally designing the detection circuit in the battery system, good detection results can be achieved for different types of external devices during the charging and discharging process when the battery system is connected to external devices. This ensures compatibility with various external devices and effectively improves the compatibility and adaptability of the battery system.

[0075] According to some embodiments of this application, a first supply voltage U1 is applied to a first voltage terminal P1 when the battery management system is woken up.

[0076] In some embodiments, the detection voltage at voltage detection node A can be obtained using ADC (Analog-to-Digital Converter) sampling. A first supply voltage U1 can be used as a pull-up source for ADC sampling. As described above, the first supply voltage U1 is applied to the first voltage terminal P1 according to the state of the battery management system. Typically, the battery management system may be in a wake-up state or a sleep state. In a wake-up state, the battery management system is in normal operation, capable of real-time monitoring of battery status and timely response to battery status changes and external commands. In a sleep state, the battery management system may disable some unnecessary functions, reduce the frequency of battery status monitoring, and operate in a low-power state. In some embodiments, a sleep-state battery management system can be woken up upon receiving a wake-up signal and switched to a wake-up state.

[0077] In the embodiments of this application, the first supply voltage U1 can be applied to the first voltage terminal P1 only when the battery management system is in a wake-up state, and when the battery management system is in a sleep state, the first supply voltage U1 is not applied to the first voltage terminal P1.

[0078] The first power supply voltage is applied to the first voltage terminal only after the battery management system is woken up. This enables the normal wake-up function of the battery management system while being compatible with the charge and discharge detection of different devices, reducing the risk that the battery management system cannot be woken up properly when connected to external devices.

[0079] According to some embodiments of this application, the first switch Q1 is used to connect the first voltage terminal P1 to the voltage detection node A when the battery management system is woken up.

[0080] In some embodiments, the conduction of the first switch Q1 can be synchronized with the application of the first supply voltage U1 to the first voltage terminal P1. When the battery management system is in a wake-up state, the first supply voltage U1 is applied to the first voltage terminal P1, and the first switch Q1 is turned on, thereby enabling voltage detection of voltage detection node A. When the battery management system is in a sleep state, the first supply voltage U1 is no longer applied to the first voltage terminal P1, and the first switch Q1 remains in the off state.

[0081] In some embodiments, the first switch Q1 can be connected to a corresponding control circuit, which controls its on or off state.

[0082] It should be understood that the first switch Q1 can be any type of switching component, as long as it can realize the connection between the first voltage terminal P1 and the voltage detection node A. This application does not limit this.

[0083] By properly controlling the conduction time of the first switch, the reliability of the detection process can be improved, while the normal wake-up function of the battery management system can be realized.

[0084] According to some embodiments of this application, the resistance of the first detection resistor R1 is greater than or equal to 900 ohms and less than or equal to 1100 ohms.

[0085] As mentioned above, when an external device is connected to the battery system, the equivalent resistance Rin and the first detection resistor R1 form a voltage divider. Therefore, the resistance value of the first detection resistor R1 can be set to a suitable value, so that different detection voltages can be obtained for different equivalent resistances Rin.

[0086] In one example, the first sensing resistor R1 can be chosen to have a resistance of 1 kΩ. Considering a resistance tolerance of 3%, the resistance of the first sensing resistor R1 may be in the range of 970Ω to 1030Ω. That is, the lower limit of the first sensing resistor R1 is R1min = 970Ω, the typical value is R1typ = 1000Ω, and the upper limit is R1max = 1030Ω. The first supply voltage U1 is set to 5V. Considering a voltage tolerance of 2%, the lower limit of the first supply voltage U1 is U1min = 4.9V, the typical value is U1typ = 5V, and the upper limit is U1max = 5.1V. The offset voltage Vgnd of the power supply ground GND is assumed to be 0.1V. Voltage detection is performed using ADC sampling, and the ADC sampling error is assumed to be 6 LSB (Least Significant Bit), 12 bits.

[0087] Regarding the equivalent resistance Rin corresponding to different external devices mentioned above, for example, in the Chinese standard scenario, the equivalent resistance for a charging current of 63A is 100Ω (hereinafter referred to as 100Ω (charging 63A)), the equivalent resistance for a charging current of 32A is 220Ω (hereinafter referred to as 220Ω (charging 32A)), the equivalent resistance for a charging current of 32A is 680Ω (hereinafter referred to as 680Ω (charging 32A)), and the equivalent resistance for a charging current of 16A is 1500Ω (hereinafter referred to as 1500Ω (charging 16A)). In the European standard scenario... The equivalent resistances corresponding to the discharge currents of 63A and 32A are 470Ω (indicated as 470Ω (discharge 63A)), 1000Ω (indicated as 1000Ω (discharge 32A)), 16A and 10A are 2700Ω (indicated as 2700Ω (discharge 10A)). Similarly, considering a resistance error of 3%, the lower limit Rin min, typical resistance Rin typ, and upper limit Rin of the equivalent resistance Rin are calculated respectively.

[0088] Based on the calculation formula U = (U1 × Rin / (R1 + Rin)) × 1000mV mentioned above, and considering the error of the first sensing resistor R1, the following formula can be further obtained:

[0089] Utyp=(U1typ×Rin typ / (R1typ+Rin typ))×1000mV;

[0090] Umin=((U1min×Rin min / (R1max+Rin min)-Vgnd)×U1min / (2^12-1)-6LSB)×(U1typ / (2^12-1))×1000mV;

[0091] Umax=((U1max×Rin max / (R1min+Rin max)×U1max / (2^12-1)+6LSB)×(U1typ / (2^12-1))×1000mV.

[0092] For the different equivalent resistances mentioned above under the national standard and European standard scenarios, the detection voltage range at voltage detection node A can be calculated as follows:

[0093] The detection voltage range for 100Ω (63A charging) is [331, 488] mV;

[0094] The detection voltage range for 220Ω (32A charging) is [767, 954] mV;

[0095] The detection voltage range for 470Ω (discharge 63A) is [1457, 1672] mV;

[0096] The detection voltage range for 680Ω (32A charging) is [1883, 2104] mV;

[0097] The detection voltage range for 1000Ω (32A discharge) is [2366, 2582] mV;

[0098] The detection voltage range for 1500Ω (charging 16A) is [2878, 3079] mV;

[0099] The detection voltage range for 2000Ω (discharge 16A) is [3224, 3406] mV;

[0100] The detection voltage range for 2700Ω (discharge 10A) is [3553, 3714] mV.

[0101] As can be seen from the voltage detection ranges described above, there is no overlap between them. After obtaining the detection voltage at voltage detection node A using an ADC, the range of this detection voltage can be used to accurately determine which external device is connected to the battery system, reducing the risk of misjudgment.

[0102] Setting the resistance value of the first detection resistor within a suitable range allows it to be compatible with external devices that have different electrical performance parameters, and accurately identifies the type of external device.

[0103] According to some embodiments of this application, the detection circuit 11 further includes a first filter circuit.

[0104] The first filter circuit is connected between voltage detection node A and power ground GND, and is used to filter interference signals in detection circuit 11.

[0105] The power ground is the reference equipotential point of the power supply in the circuit, used to form a complete current loop. A filter circuit can also be set between the voltage detection node A and the power ground GND in the detection circuit 11 to filter out interference signals in the circuit.

[0106] By incorporating a first filter circuit into the detection circuit, interference signals in the circuit can be suppressed, thereby improving the accuracy of the detection results.

[0107] According to some embodiments of this application, reference is made to Figure 3 The first filter circuit includes a first filter capacitor C1.

[0108] The first filter capacitor C1 is connected between voltage sensing node A and power ground GND.

[0109] like Figure 3 As shown, the first filter circuit between voltage detection node A and power ground GND may include a first filter capacitor C1, which achieves the filtering effect through the capacitor.

[0110] Using capacitors for filtering can simplify circuit design while achieving good filtering results.

[0111] According to some embodiments of this application, reference is made to Figure 3 The first filter circuit includes a first filter resistor R2 and a second filter capacitor C2.

[0112] The first terminal of the first filter resistor R2 is connected to the voltage detection node A.

[0113] The second filter capacitor C2 is connected between the second terminal of the first filter resistor R2 and the power ground GND.

[0114] like Figure 3 As shown, the first filter circuit may also include a first filter resistor R2 and a second filter capacitor C2. The first filter resistor R2 and the second filter capacitor C2 form an RC circuit, which can also achieve good filtering functionality. Figure 3 In the example shown, the detection voltage is sampled by an ADC at the end where the first filter resistor R2 is connected to the second filter capacitor C2, so that the sampling result can be obtained after filtering out the interference signal, thereby reducing the detection error.

[0115] Using resistors and capacitors to form a filter circuit can improve the suppression of interference signals.

[0116] According to some embodiments of this application, the detection circuit 11 also includes a protection circuit.

[0117] The protection circuit is connected between voltage detection node A and power ground GND to provide voltage protection for detection circuit 11.

[0118] In the battery system, a protection circuit can also be set up to suppress instantaneous high voltage and / or instantaneous high current that occur in the circuit.

[0119] Using protective circuits can effectively suppress large transient voltages in the circuit and reduce the risk of circuit damage.

[0120] According to some embodiments of this application, reference is made to Figure 3 The protection circuit includes transient suppression diode DZ1.

[0121] like Figure 3 As shown, a transient voltage suppressor diode DZ1 can be installed between voltage detection node A and power ground GND as a protection circuit. The transient voltage suppressor diode DZ1 can be, for example, a transient voltage suppressor diode TVS (Transient Voltage Suppressor) to provide fast overvoltage protection for the circuit.

[0122] Using transient suppression diodes can simplify circuit design while achieving better voltage protection.

[0123] According to some embodiments of this application, reference is made to Figure 4 The charging and discharging circuit 10 also includes a wake-up circuit 12.

[0124] The wake-up circuit 12 and the detection circuit 11 are connected via voltage detection node A. The wake-up circuit 12 is used to generate a wake-up signal in response to the connection of the charging / discharging circuit 10 with an external device. The wake-up signal is used to wake up the battery management system.

[0125] like Figure 4 As shown, a wake-up circuit 12 can also be provided in the charging / discharging circuit 10. As mentioned above, the battery management system can be in a sleep state and a wake-up state. If the battery management system is in a sleep state and an external device is connected to the battery system, such as a charging gun being inserted into the charging interface, the battery management system needs to be woken up in time to perform corresponding management and control.

[0126] The wake-up circuit 12 can generate a wake-up signal when an external device is connected to the battery system, thereby quickly waking up the battery management system. It should be understood that the wake-up signal can be a newly generated signal when the external device is connected to the battery system, or it can be a signal represented by a change in parameters such as voltage (e.g., from low level to high level) when the external device is connected to the battery system.

[0127] By using detection and wake-up circuits together, the battery management system can be woken up in a timely manner when an external device is connected to the battery system, thus enabling the corresponding functions.

[0128] According to some embodiments of this application, reference is made to Figure 4 The wake-up circuit 12 includes a second voltage terminal P2, a third voltage terminal P3, a fourth voltage terminal P4, multiple detection resistors, and multiple switches.

[0129] The second voltage terminal P2 is used to receive the second power supply voltage U2.

[0130] The third voltage terminal P3 is used to receive the first supply voltage U1. The first supply voltage U1 is applied to the third voltage terminal P3 when the battery management system is awakened.

[0131] The fourth voltage terminal P4 is used to receive the second power supply voltage U2.

[0132] Multiple sensing resistors are used to divide the second supply voltage U2 and / or the first supply voltage U1.

[0133] Multiple switches are used to switch the connection relationship between multiple sensing resistors.

[0134] like Figure 4 As shown, the wake-up circuit 12 receives a first supply voltage U1 and a second supply voltage U2. Similar to the first voltage terminal P1 in the detection circuit 11, the first supply voltage U1 is not constantly applied to the third voltage terminal P3, but is only applied to the third voltage terminal P3 after the battery management system is woken up. The second supply voltage U2, however, is constantly applied to the second voltage terminal P2 and the fourth voltage terminal P4, regardless of whether the battery management system is in a sleep state or a wake-up state. It should be noted that although in... Figure 4 While these components are shown as independent of each other, in circuit design, voltage terminals receiving the same supply voltage can be connected to each other, or they can use the same pad on the circuit board, for example... Figure 4 The second voltage terminal P2 and the fourth voltage terminal P4 can be connected to each other or use the same pad, and the first voltage terminal P1 and the third voltage terminal P3 can be connected to each other or use the same pad, etc. This application does not limit this.

[0135] The specific design of the detection resistor and switch in the wake-up circuit 12 will be described in detail below.

[0136] A well-designed wake-up circuit can enable the battery management system to perform normal wake-up functions and improve the reliability of the wake-up process.

[0137] According to some embodiments of this application, the plurality of switches includes a second switch Q4.

[0138] The second switch Q4 is connected to voltage detection node A, the fourth voltage terminal P4 and power ground GND, and is used to disconnect the charging and discharging circuit 10 when it is not connected to the external device and to turn it on when it is connected to the external device.

[0139] like Figure 4 As shown, a second switch Q4 is provided in the wake-up circuit 12. When a certain voltage is presented between the first node F and the second node G, the second switch Q4 can turn on or off the connection between the second node G and the third node H. In one example, the second switch Q4 can be a P-channel MOS transistor (P-MOS).

[0140] By setting the second switch to be on and off, the battery management system can be woken up when an external device is connected to the battery system.

[0141] According to some embodiments of this application, the plurality of switches also includes a third switch Q2.

[0142] The third switch Q2 is connected to voltage detection node A, the second switch Q4 and the third voltage terminal P3, and is used to turn on the charging and discharging circuit 10 when it is not connected to external devices and to turn off the circuit when the battery management system is woken up.

[0143] like Figure 4 As shown, a third switch Q2 is also provided in the wake-up circuit 12. When a certain voltage is applied between the fourth node D and the fifth node E, the third switch Q2 can turn on or off the connection between the sixth node C and the fourth node D. In one example, the third switch Q2 can be a P-channel MOS transistor (P-MOS).

[0144] By setting the third switch to be on and off, the stability and reliability of the charging and discharging circuit can be improved while enabling the battery management system to be woken up normally.

[0145] According to some embodiments of this application, the plurality of switches also includes a fourth switch Q3.

[0146] The fourth switch Q3 is connected to the second switch Q4, the power ground GND, the third voltage terminal P3, and the fourth switch Q3. It is used to disconnect the charging and discharging circuit 10 when it is not connected to external devices and to turn on when the battery management system is woken up.

[0147] like Figure 4 As shown, a fourth switch Q3 is also provided in the wake-up circuit 12. When the fifth node E presents a certain voltage, the fourth switch Q3 can turn on or off the connection between the first node F and the power supply ground GND. In one example, the fourth switch Q3 can be an N-channel MOS transistor (N-MOS).

[0148] By setting the fourth switch to be on and off, the impact on other functions of the battery system can be reduced while ensuring the normal wake-up of the battery management system, thereby improving the reliability of the battery system.

[0149] According to some embodiments of this application, the plurality of detection resistors include a second detection resistor R4, a third detection resistor R5, a fourth detection resistor R7, a fifth detection resistor R8, a sixth detection resistor R9, and a seventh detection resistor R10.

[0150] The second sensing resistor R4 is connected to the third voltage terminal P3 and the third switch Q2.

[0151] The third detection resistor R5 is connected to the second voltage terminal P2, the third switch Q2, and the second switch Q4.

[0152] The fourth detection resistor R7 is connected to the third detection resistor R5, the third switch Q2, and the fourth switch Q3.

[0153] The fifth sensing resistor R8 is connected to the second sensing resistor R4, the fourth sensing resistor R7, and the power ground GND.

[0154] The sixth sensing resistor R9 is connected to the fourth voltage terminal P4 and the second switch Q4.

[0155] The seventh sensing resistor R10 is connected to the second switch Q4 and the power ground GND.

[0156] like Figure 4 As shown, multiple detection resistors can be set in the wake-up circuit 12. These detection resistors can divide the second supply voltage U2 applied to the second voltage terminal P2 and the fourth voltage terminal P4, and the first supply voltage U1 applied to the third voltage terminal P3, thereby enabling the second switch Q4, the third switch Q2, and the fourth switch Q3 to be turned on or off.

[0157] exist Figure 4In the example shown, when the external device is not connected to the battery system, i.e., when the equivalent resistance Rin is not connected to the charging / discharging circuit 10 (e.g., when the charging gun is not inserted into the charging port), the battery management system may be in a sleep state. Since the second supply voltage U2 continues to be applied even when the battery management system is in sleep mode, there is a certain voltage Ved between the fifth node E and the fourth node D. Ved allows the third switch Q2 to conduct. Because the battery management system is in sleep mode, the first supply voltage U1 is not applied to the third voltage terminal P3. The voltage Ve at the fifth node E is very small, causing the fourth switch Q3 to be in a non-conducting state, and there is no connection between the first node F and the power ground GND. The voltage Vf at the first node F is equal to U2. The voltage Vgf between the second node G and the first node F is very small, causing the second switch Q4 to also be in a non-conducting state, and there is no connection between the second node G and the third node H. The third node H is at a low level and will not wake up the battery management system.

[0158] When an external device is connected to the battery system, i.e., when the equivalent resistance Rin is connected to the charging / discharging circuit 10, such as when a charging gun is inserted into the charging port, since the third switch Q2 is still conducting, the voltage Vf at the first node F is pulled down to a low level, and the voltage Vgf between the second node G and the first node F increases, causing the second switch Q4 to conduct, and the second node G and the third node H to conduct. The voltage Vh at the third node H becomes high, i.e., the wake-up signal becomes high, which will wake up the battery management system, activate the battery management system to start working, and maintain the wake-up state. After the battery management system is woken up, the first supply voltage U1 will be applied to the third voltage terminal P3. Due to the presence of the first supply voltage U1, the voltage Ved between the fifth node E and the fourth node D decreases, which will cause the third switch Q2 to turn off. The turning off of the third switch Q2 will cause the sixth node C and the fourth node D to disconnect, thereby reducing the impact of the wake-up circuit 12 on voltage sampling. In addition, due to the presence of the first power supply voltage U1, the voltage Ve at the fifth node E increases, which will also cause the fourth switch Q3 to conduct, so that the first node F is connected to the power supply ground GND, and the voltage Vf at the first node F remains at a low level, thereby enabling the second switch Q4 to continue to conduct.

[0159] By setting the position and connection relationship of each detection resistor, accurate control of each switch can be achieved through voltage division, making the wake-up process more reliable and precise.

[0160] According to some embodiments of this application, the resistance of the second detection resistor R4 is greater than or equal to 50 ohms and less than or equal to 150 ohms, the resistance of the third detection resistor R5 is greater than or equal to 4.5 kΩ and less than or equal to 5.5 kΩ, the resistance of the fourth detection resistor R7 is greater than or equal to 0.9 MΩ and less than or equal to 1.1 MΩ, the resistance of the fifth detection resistor R8 is greater than or equal to 9.5 kΩ and less than or equal to 10.5 kΩ, the resistance of the sixth detection resistor R9 is greater than or equal to 14 kΩ and less than or equal to 16 kΩ, and the resistance of the seventh detection resistor R10 is greater than or equal to 99 kΩ and less than or equal to 101 kΩ.

[0161] As mentioned above, the resistance values ​​of each detection resistor will affect the voltage of each node in the wake-up circuit 12, and they all need to be set to appropriate resistance values. In one example, the resistance value of the second detection resistor R4 can be set to 100Ω, the resistance value of the third detection resistor R5 can be set to 5kΩ, the resistance value of the fourth detection resistor R7 can be set to 1MΩ, the resistance value of the fifth detection resistor R8 can be set to 10kΩ, the resistance value of the sixth detection resistor R9 can be set to 15kΩ, and the resistance value of the seventh detection resistor R10 can be set to 100kΩ.

[0162] By setting the resistance values ​​of each detection resistor, accurate control of each switch can be achieved through voltage division, making the wake-up process more reliable and precise.

[0163] As mentioned above, the first supply voltage U1 will be applied to the first voltage terminal P1 when the battery management system is woken up, and the first switch Q1 will also be turned on when the battery management system is woken up. When the battery management system is in a dormant state, the first switch Q1 is not turned on, so that the second supply voltage U2 continuously applied to the second voltage terminal P2 will not form a circuit with the power ground GND through the second switch Q4, the first detection resistor R1 and other components. Therefore, when an external device is connected to the battery system, the wake-up function of the battery management system can be realized normally.

[0164] According to some embodiments of this application, the plurality of sensing resistors further includes at least one of an eighth sensing resistor R3 and a ninth sensing resistor R6.

[0165] The eighth sensing resistor R3 is connected to voltage sensing node A and the third switch Q2.

[0166] The ninth detection resistor R6 is connected to the second switch Q4 and the third switch Q2.

[0167] like Figure 4 As shown, a current-limiting resistor can also be set in the wake-up circuit 12. The eighth detection resistor R3 and the ninth detection resistor R6 can achieve the current-limiting function and can be used according to the application scenario.

[0168] Including a current-limiting resistor in the circuit can reduce the risk of damage to the circuit due to excessive current and improve reliability.

[0169] According to some embodiments of this application, the resistance of the eighth detection resistor R3 is greater than or equal to 4.9 kΩ and less than or equal to 5.5 kΩ, and the resistance of the ninth detection resistor R6 is greater than or equal to 9.5 kΩ and less than or equal to 10.5 kΩ.

[0170] In one example, the resistance of the eighth sensing resistor R3 can be set to 5.1kΩ, and the resistance of the ninth sensing resistor R6 can be set to 10kΩ.

[0171] Setting the current-limiting resistor appropriately can improve the reliability and stability of the circuit.

[0172] exist Figure 4 In the example shown, the wake-up signal can be the voltage Vh at the third node H, using Figure 4 The charging / discharging circuit 10 shown, after the battery management system is woken up, will maintain a high voltage Vh at the third node H due to the conduction of the second switch Q4, thus keeping the battery management system in a woken-up state. In some embodiments, the wake-up signal, i.e., the voltage Vh at the third node H, can be connected to the EN enable pin of the power management chip. This connection method ensures that the wake-up signal does not affect the sleep function. When a sleep command is sent, the battery management system can enter a sleep state, and the battery management system can still achieve the sleep function even when an external device is connected to the battery system, such as when a charging gun is inserted into the charging interface.

[0173] In other embodiments, the edge wake-up function can also be implemented through the wake-up circuit 12, that is, the wake-up function is implemented by using the switching of high and low level edges as the wake-up signal. Edge wake-up can trigger the battery management system to wake up from the sleep state by detecting the level transition of the signal (e.g., rising edge or falling edge), rather than relying on a continuous high / low level to achieve the wake-up function.

[0174] According to some embodiments of this application, reference is made to Figure 5 The wake-up circuit 12 also includes a fifth voltage terminal P5 and a sixth voltage terminal P6.

[0175] The fifth voltage terminal P5 is used to receive the second power supply voltage U2.

[0176] The sixth voltage terminal P6 is used to receive the second power supply voltage U2.

[0177] Figure 5 The diagram illustrates an example of a charging / discharging circuit 10 capable of edge-to-wake functionality. For example... Figure 5As shown, the second power supply voltage U2 can also be applied to the fifth voltage terminal P5 and the sixth voltage terminal P6. As mentioned above, the fifth voltage terminal P5 and the sixth voltage terminal P6 can also be connected to other voltage terminals that receive the second power supply voltage U2 or use the same pad, etc.

[0178] The accuracy of the wake-up function can be further improved by increasing the voltage terminal that receives the power supply voltage.

[0179] According to some embodiments of this application, reference is made to Figure 5 The multiple switches also include a fifth switch Q5 and a sixth switch Q6.

[0180] The fifth switch Q5 is connected to the fifth voltage terminal P5 and the power ground GND, and is used to disconnect the charging and discharging circuit 10 when it is not connected to an external device and to turn it on when it is connected to an external device.

[0181] The sixth switch Q6 is connected to the sixth voltage terminal P6 and the power ground GND, and is used to disconnect the charging and discharging circuit 10 when it is not connected to an external device and to turn it on when it is connected to an external device.

[0182] like Figure 5 As shown, a fifth switch Q5 and a sixth switch Q6 can also be provided in the wake-up circuit 12. By turning the fifth switch Q5 and the sixth switch Q6 on and off, the edge wake-up function of the battery management system can be realized.

[0183] By adding a corresponding switch, edge wake-up functionality can be achieved, and the battery management system can also enter sleep mode when the battery system is connected to external devices.

[0184] According to some embodiments of this application, the wake-up circuit 12 further includes a loop capacitor C4.

[0185] The circuit capacitor C4 is connected to the fifth voltage terminal P5 and the sixth switch Q6.

[0186] like Figure 5 As shown, due to the characteristics of capacitance, the voltage across the circuit capacitor C4 will not experience a significant sudden change.

[0187] By setting the loop capacitor, the reliability of the edge wake-up function can be improved.

[0188] According to some embodiments of this application, the plurality of detection resistors further include a tenth detection resistor R13, an eleventh detection resistor R14, and a twelfth detection resistor R12.

[0189] The tenth sensing resistor R13 is connected to the sixth voltage terminal P6, the sixth switch Q6, and the loop capacitor C4.

[0190] The eleventh detection resistor R14 is connected to the sixth switch Q6 and the power ground GND.

[0191] The twelfth sensing resistor R12 is connected to the fifth voltage terminal P5 and the fifth switch Q5.

[0192] like Figure 5 As shown, other detection resistors can be further provided in the detection circuit 11. These detection resistors can divide the second supply voltage U2 applied to the fifth voltage terminal P5 and the sixth voltage terminal P6, thereby enabling the fifth switch Q5 and the sixth switch Q6 to be turned on or off.

[0193] exist Figure 5 In the example shown, when the external device is not connected to the battery system, that is, when the equivalent resistance Rin is not connected to the charging / discharging circuit 10, such as when the charging gun is not plugged into the charging port, the battery management system may be in a dormant state. Figure 4 Similar to the example in [previous example], in this case, the third switch Q2 is on, while the second switch Q4 and the fourth switch Q3 are off. Since the voltage across the loop capacitor C4 is stable, the voltage Vkj between the seventh node K and the eighth node J is small, and the sixth switch Q6 is in the off state. There is no conduction between the seventh node K and the ninth node L, and the ninth node L is at a low level, which will not wake up the battery management system.

[0194] When an external device is connected to the battery system, that is, when the equivalent resistance Rin is connected to the charging / discharging circuit 10, for example, when the charging gun is inserted into the charging port, it is connected to... Figure 4 Similar to the example in [example 1], when the second switch Q4 is turned on, the voltage Vh at the third node H becomes high, causing the fifth switch Q5 to turn on, and the voltage Vi at the tenth node I changes from high to low. Since the voltage across the loop capacitor C4 cannot change abruptly, the voltage Vj at the eighth node J also becomes low, increasing the voltage Vkj between the seventh node K and the eighth node J, causing the sixth switch Q6 to turn on. At this time, the voltage Vl at the ninth node L rises from low to high, i.e., a voltage jump occurs, triggering the edge wake-up function. The wake-up signal will activate the battery management system. Figure 4Similar to the example in [example 1], after the battery management system is woken up, the first supply voltage U1 will be applied to the third voltage terminal P3, the third switch Q2 will be turned off, and the fourth switch Q3 will be turned on, connecting the first node F to the power ground GND, and the voltage Vf at the first node F will remain low. If, in this state, i.e., when the external device is connected to the battery system, the battery management system needs to enter sleep mode, the first supply voltage U1 will not continue to be applied. After the first supply voltage U1 stops being applied, since the voltage Vf remains low, the voltage across the circuit capacitor C4 will not change abruptly. This means that although the external device remains connected to the battery system, even if the battery management system enters sleep mode, the voltage across the circuit capacitor C4 will not change abruptly and repeatedly wake up the battery management system, thus supporting the plug-in sleep function.

[0195] By setting the position and connection relationship of each sensing resistor, accurate control of each switch can be achieved through voltage division, making the edge wake-up process more reliable and precise.

[0196] According to some embodiments of this application, the wake-up circuit 12 further includes a second filter circuit.

[0197] The second filter circuit is connected between the second switch Q4 and the power ground GND, and is used to filter the interference signals in the wake-up circuit 12.

[0198] Similar to the detection circuit 11, the wake-up circuit 12 can also be equipped with a filter circuit to filter out interference signals in the circuit.

[0199] By incorporating a second filter circuit into the detection circuit, interference signals in the circuit can be suppressed, thereby improving the accuracy of the detection results.

[0200] According to some embodiments of this application, the second filter circuit includes a second filter resistor R11 and a third filter capacitor C3.

[0201] The first terminal of the second filter resistor R11 is connected to the second switch Q4.

[0202] The third filter capacitor C3 is connected between the second terminal of the second filter resistor R11 and the power ground GND.

[0203] like Figure 4 and Figure 5 As shown, the second filter circuit located between the second switch Q4 and the power ground GND can also include a second filter resistor R11 and a third filter capacitor C3. The second filter resistor R11 and the third filter capacitor C3 form an RC circuit, which can also achieve good filtering function.

[0204] Using resistors and capacitors to form a filter circuit can improve the suppression of interference signals.

[0205] In some embodiments, the wake-up circuit 12 may also include components such as diode D1. Diode D1 provides reverse polarity protection, reducing the risk of external voltage interference affecting normal circuit operation. It should be understood that... Figures 3 to 5 These are merely examples of the charging and discharging circuit 10. In other embodiments, the charging and discharging circuit 10 may include other components or omit some components, and this application does not limit this.

[0206] Based on the same technical concept, this application provides a battery management system, including the charging and discharging circuit 10 in the above embodiments.

[0207] Based on the same technical concept, embodiments of this application provide a battery system, including the battery management system described in the above embodiments.

[0208] The embodiments of the battery system and battery management system can refer to the embodiment of the charging and discharging circuit 10, and the repeated parts will not be described again.

[0209] A specific embodiment of this application is described below. It should be understood that this specific embodiment is described for illustrative purposes only and should not be construed as limiting the scope of this application.

[0210] like Figure 4 and Figure 5 As shown, the battery system includes a charging / discharging circuit 10. The charging / discharging circuit 10 includes a detection circuit 11 and a wake-up circuit 12. The wake-up circuit 12 is connected to the detection circuit 11 via a voltage detection node A.

[0211] The detection circuit 11 includes a voltage detection node A, a first voltage terminal P1, a first switch Q1, and a first detection resistor R1. When the battery management system is in a wake-up state, a first supply voltage U1 is applied to the first voltage terminal P1, and the first switch Q1 is turned on, thereby enabling voltage detection at the voltage detection node A. When the battery management system is in a sleep state, the first supply voltage U1 is no longer applied to the first voltage terminal P1, and the first switch Q1 remains open.

[0212] The first sensing resistor R1 can be 1kΩ. Considering a 3% resistance error, the value of the first sensing resistor R1 may be in the range of 970Ω to 1030Ω. That is, the lower limit of the first sensing resistor R1 is R1min = 970Ω, the typical value is R1typ = 1000Ω, and the upper limit is R1max = 1030Ω. The first supply voltage U1 is set to 5V. Considering a 2% voltage error, the lower limit of the first supply voltage U1 is U1min = 4.9V, the typical value is U1typ = 5V, and the upper limit is U1max = 5.1V. The offset voltage Vgnd of the power supply ground GND is assumed to be 0.1V. Voltage detection is performed using ADC sampling, and the ADC sampling error is assumed to be 6LSB (Least Significant Bit), 12 bits.

[0213] For the equivalent resistance Rin corresponding to different external devices, such as 100Ω (charging 63A), 220Ω (charging 32A), 680Ω (charging 32A), and 1500Ω (charging 16A) under the national standard scenario, and 470Ω (discharging 63A), 1000Ω (discharging 32A), 2000Ω (discharging 16A), and 2700Ω (discharging 10A) under the European standard scenario, the lower limit Rin min, the typical resistance value Rin typ, and the upper limit Rin max of the equivalent resistance are calculated respectively, taking into account the resistance error of 3%.

[0214] According to the following formula:

[0215] Utyp=(U1typ×Rin typ / (R1typ+Rin typ))×1000mV;

[0216] Umin=((U1min×Rin min / (R1max+Rin min)-Vgnd)×U1min / (2^12-1)-6LSB)×(U1typ / (2^12-1))×1000mV;

[0217] Umax=((U1max×Rin max / (R1min+Rin max)×U1max / (2^12-1)+6LSB)×(U1typ / (2^12-1))×1000mV.

[0218] For the different equivalent resistances mentioned above under the national standard and European standard scenarios, the detection voltage range at voltage detection node A can be calculated as follows:

[0219] The detection voltage range for 100Ω (63A charging) is [331, 488] mV;

[0220] The detection voltage range for 220Ω (32A charging) is [767, 954] mV;

[0221] The detection voltage range for 470Ω (discharge 63A) is [1457, 1672] mV;

[0222] The detection voltage range for 680Ω (32A charging) is [1883, 2104] mV;

[0223] The detection voltage range for 1000Ω (32A discharge) is [2366, 2582] mV;

[0224] The detection voltage range for 1500Ω (charging 16A) is [2878, 3079] mV;

[0225] The detection voltage range for 2000Ω (discharge 16A) is [3224, 3406] mV;

[0226] The detection voltage range for 2700Ω (discharge 10A) is [3553, 3714] mV.

[0227] Once the voltage at voltage detection node A is obtained using ADC sampling, the range of this voltage can be used to accurately determine which external device the battery system is connected to, reducing the risk of misjudgment.

[0228] The detection circuit 11 also includes a first filter circuit and a protection circuit. For example... Figure 4 As shown, the first filter circuit includes a first filter capacitor C1, a first filter resistor R2, and a second filter capacitor C2. The protection circuit may include a transient suppression diode DZ1.

[0229] like Figure 4 As shown, the wake-up circuit 12 includes a second voltage terminal P2, a third voltage terminal P3, a fourth voltage terminal P4, multiple detection resistors, and multiple switches. The multiple switches include a second switch Q4, a third switch Q2, and a fourth switch Q3. The multiple resistors include a second detection resistor R4, a third detection resistor R5, a fourth detection resistor R7, a fifth detection resistor R8, a sixth detection resistor R9, a seventh detection resistor R10, an eighth detection resistor R3, and a ninth detection resistor R6.

[0230] exist Figure 4In the example shown, when the external device is not connected to the battery system, i.e., when the equivalent resistance Rin is not connected to the charging / discharging circuit 10 (e.g., when the charging gun is not inserted into the charging port), the battery management system may be in a sleep state. Since the second supply voltage U2 continues to be applied even when the battery management system is in sleep mode, there is a certain voltage Ved between the fifth node E and the fourth node D. Ved allows the third switch Q2 to conduct. Because the battery management system is in sleep mode, the first supply voltage U1 is not applied to the third voltage terminal P3. The voltage Ve at the fifth node E is very small, causing the fourth switch Q3 to be in a non-conducting state, and there is no connection between the first node F and the power ground GND. The voltage Vf at the first node F is equal to U2. The voltage Vgf between the second node G and the first node F is very small, causing the second switch Q4 to also be in a non-conducting state, and there is no connection between the second node G and the third node H. The third node H is at a low level and will not wake up the battery management system.

[0231] When an external device is connected to the battery system, i.e., when the equivalent resistance Rin is connected to the charging / discharging circuit 10, such as when a charging gun is inserted into the charging port, since the third switch Q2 is still conducting, the voltage Vf at the first node F is pulled down to a low level, and the voltage Vgf between the second node G and the first node F increases, causing the second switch Q4 to conduct, and the second node G and the third node H to conduct. The voltage Vh at the third node H becomes high, i.e., the wake-up signal becomes high, which will wake up the battery management system, activate the battery management system to start working, and maintain the wake-up state. After the battery management system is woken up, the first supply voltage U1 will be applied to the third voltage terminal P3. Due to the presence of the first supply voltage U1, the voltage Ved between the fifth node E and the fourth node D decreases, which will cause the third switch Q2 to turn off. The turning off of the third switch Q2 will cause the sixth node C and the fourth node D to disconnect, thereby reducing the impact of the wake-up circuit 12 on voltage sampling. Furthermore, due to the presence of the first supply voltage U1, the voltage Ve at the fifth node E increases, which also turns on the fourth switch Q3, connecting the first node F to the power ground GND. The voltage Vf at the first node F remains low, thus allowing the second switch Q4 to remain on. In some embodiments, the wake-up signal, i.e., the voltage Vh at the third node H, can be connected to the enable pin of the power management chip. When a sleep command is sent, the battery management system can enter a sleep state. Even when an external device is connected to the battery system, such as when a charging gun is inserted into the charging port, the battery management system can still achieve the sleep function.

[0232] Figure 5 The example shown demonstrates edge-to-wake functionality. Figure 5In the example shown, the wake-up circuit 12 further includes a fifth voltage terminal P5 and a sixth voltage terminal P6, as well as a loop capacitor C4. The multiple switches also include a fifth switch Q5 and a sixth switch Q6, and the multiple detection resistors also include a tenth detection resistor R13, an eleventh detection resistor R14, and a twelfth detection resistor R12.

[0233] exist Figure 5 In the example shown, when the external device is not connected to the battery system, that is, when the equivalent resistance Rin is not connected to the charging / discharging circuit 10, such as when the charging gun is not plugged into the charging port, the battery management system may be in a dormant state. Figure 4 Similar to the example in [previous example], in this case, the third switch Q2 is on, while the second switch Q4 and the fourth switch Q3 are off. Since the voltage across the loop capacitor C4 is stable, the voltage Vkj between the seventh node K and the eighth node J is small, and the sixth switch Q6 is in the off state. There is no conduction between the seventh node K and the ninth node L, and the ninth node L is at a low level, which will not wake up the battery management system.

[0234] When an external device is connected to the battery system, that is, when the equivalent resistance Rin is connected to the charging / discharging circuit 10, for example, when the charging gun is inserted into the charging port, it is connected to... Figure 4 Similar to the example in [example 1], when the second switch Q4 is turned on, the voltage Vh at the third node H becomes high, causing the fifth switch Q5 to turn on, and the voltage Vi at the tenth node I changes from high to low. Since the voltage across the loop capacitor C4 cannot change abruptly, the voltage Vj at the eighth node J also becomes low, increasing the voltage Vkj between the seventh node K and the eighth node J, causing the sixth switch Q6 to turn on. At this time, the voltage Vl at the ninth node L rises from low to high, i.e., a voltage jump occurs, triggering the edge wake-up function. The wake-up signal will activate the battery management system. Figure 4 Similar to the example in [example 1], after the battery management system is woken up, the first supply voltage U1 will be applied to the third voltage terminal P3, the third switch Q2 will be turned off, and the fourth switch Q3 will be turned on, connecting the first node F to the power ground GND, and the voltage Vf at the first node F will remain low. If, in this state, i.e., when the external device is connected to the battery system, the battery management system needs to enter sleep mode, the first supply voltage U1 will not continue to be applied. After the first supply voltage U1 stops being applied, since the voltage Vf remains low, the voltage across the circuit capacitor C4 will not change abruptly. This means that although the external device remains connected to the battery system, even if the battery management system enters sleep mode, the voltage across the circuit capacitor C4 will not change abruptly and repeatedly wake up the battery management system, thus supporting the plug-in sleep function.

[0235] like Figure 4 and Figure 5As shown, the wake-up circuit 12 may also include a second filter circuit. The second filter circuit includes a second filter resistor R11 and a third filter capacitor C3.

[0236] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A charging and discharging circuit, disposed in a battery system, characterized in that, The charging and discharging circuit includes: A detection circuit is used to detect the detection voltage of the voltage detection node when the charging / discharging circuit is connected to an external device. The detection circuit includes: The voltage detection node is used to connect to the external device, and the detected voltage of the voltage detection node is used to determine the type of the external device; A first voltage terminal is used to receive a first supply voltage, which is applied to the first voltage terminal based on the state of the battery management system. A first switch, connected between the first voltage terminal and the voltage detection node, is used to switch the connection relationship between the first voltage terminal and the voltage detection node; and A first sensing resistor is connected between the first voltage terminal and the voltage sensing node and is connected in series with the first switch.

2. The charging and discharging circuit according to claim 1, characterized in that, The first supply voltage is applied to the first voltage terminal when the battery management system is woken up.

3. The charging and discharging circuit according to claim 2, characterized in that, The first switch is used to connect the first voltage terminal to the voltage detection node when the battery management system is woken up.

4. The charging and discharging circuit according to claim 1, characterized in that, The resistance of the first detection resistor is greater than or equal to 900 ohms and less than or equal to 1100 ohms.

5. The charging and discharging circuit according to claim 1, characterized in that, The detection circuit further includes: The first filtering circuit is connected between the voltage detection node and the power supply ground, and is used to filter interference signals in the detection circuit.

6. The charging and discharging circuit according to claim 5, characterized in that, The first filter circuit includes: The first filter capacitor is connected between the voltage detection node and the power ground.

7. The charging and discharging circuit according to claim 5, characterized in that, The first filter circuit includes: A first filter resistor, the first terminal of which is connected to the voltage detection node; and The second filter capacitor is connected between the second terminal of the first filter resistor and the power supply ground.

8. The charging and discharging circuit according to claim 1, characterized in that, The detection circuit further includes: A protection circuit, connected between the voltage detection node and the power supply ground, is used to provide voltage protection for the detection circuit.

9. The charging and discharging circuit according to claim 8, characterized in that, The protection circuit includes transient suppression diodes.

10. The charging and discharging circuit according to any one of claims 1-9, characterized in that, Also includes: A wake-up circuit, connected to the detection circuit via the voltage detection node, is used for: In response to the connection of the charging / discharging circuit with the external device, a wake-up signal is generated, which is used to wake up the battery management system.

11. The charging and discharging circuit according to claim 10, characterized in that, The wake-up circuit includes: The second voltage terminal is used to receive the second power supply voltage; The third voltage terminal is used to receive the first power supply voltage, which is applied to the third voltage terminal when the battery management system is woken up. The fourth voltage terminal is used to receive the second power supply voltage; Multiple sensing resistors are used to divide the second supply voltage and / or the first supply voltage; and Multiple switches are used to switch the connection relationship between the multiple sensing resistors.

12. The charging and discharging circuit according to claim 11, characterized in that, The plurality of switches includes: The second switch, connected to the voltage detection node, the fourth voltage terminal, and the power ground, is used to disconnect when the charging / discharging circuit is not connected to the external device and to connect when the charging / discharging circuit is connected to the external device.

13. The charging and discharging circuit according to claim 12, characterized in that, The plurality of switches also includes: The third switch, connected to the voltage detection node, the second switch, and the third voltage terminal, is used to turn on when the charging / discharging circuit is not connected to the external device and to turn off when the battery management system is woken up.

14. The charging and discharging circuit according to claim 13, characterized in that, The plurality of switches also includes: A fourth switch, connected to the second switch, the power ground, the third voltage terminal, and the fourth switch, is used to disconnect when the charging / discharging circuit is not connected to the external device and to turn on when the battery management system is activated.

15. The charging and discharging circuit according to claim 14, characterized in that, The plurality of detection resistors include: The second detection resistor is connected to the third voltage terminal and the third switch; The third detection resistor is connected to the second voltage terminal, the third switch, and the second switch; The fourth detection resistor is connected to the third detection resistor, the third switch, and the fourth switch; The fifth detection resistor is connected to the second detection resistor, the fourth detection resistor, and the power ground. The sixth sensing resistor is connected to the fourth voltage terminal and the second switch; and The seventh detection resistor is connected to the second switch and the power ground.

16. The charging and discharging circuit according to claim 15, characterized in that, The resistance of the second detection resistor is greater than or equal to 50 ohms and less than or equal to 150 ohms; the resistance of the third detection resistor is greater than or equal to 4.5 kΩ and less than or equal to 5.5 kΩ; the resistance of the fourth detection resistor is greater than or equal to 0.9 MΩ and less than or equal to 1.1 MΩ; the resistance of the fifth detection resistor is greater than or equal to 9.5 kΩ and less than or equal to 10.5 kΩ; the resistance of the sixth detection resistor is greater than or equal to 14 kΩ and less than or equal to 16 kΩ; and the resistance of the seventh detection resistor is greater than or equal to 99 kΩ and less than or equal to 101 kΩ.

17. The charging and discharging circuit according to claim 15, characterized in that, The plurality of sensing resistors also includes at least one of the following: The eighth detection resistor is connected to the voltage detection node and the third switch; The ninth detection resistor is connected to the second switch and the third switch.

18. The charging and discharging circuit according to claim 17, characterized in that, The resistance of the eighth detection resistor is greater than or equal to 4.9 kΩ and less than or equal to 5.5 kΩ, and the resistance of the ninth detection resistor is greater than or equal to 9.5 kΩ and less than or equal to 10.5 kΩ.

19. The charging and discharging circuit according to claim 15, characterized in that, The wake-up circuit also includes: The fifth voltage terminal is used to receive the second supply voltage; and The sixth voltage terminal is used to receive the second power supply voltage.

20. The charging and discharging circuit according to claim 19, characterized in that, The plurality of switches also includes: A fifth switch, connected to the fifth voltage terminal and the power ground, is used to disconnect when the charging / discharging circuit is not connected to the external device and to connect when the charging / discharging circuit is connected to the external device; and A sixth switch, connected to the sixth voltage terminal and the power ground, is used to disconnect when the charging / discharging circuit is not connected to the external device and to connect when the charging / discharging circuit is connected to the external device.

21. The charging and discharging circuit according to claim 20, characterized in that, The wake-up circuit also includes: The loop capacitor is connected to the fifth voltage terminal and the sixth switch.

22. The charging and discharging circuit according to claim 21, characterized in that, The plurality of sensing resistors also include: The tenth detection resistor is connected to the sixth voltage terminal, the sixth switch, and the loop capacitor; The eleventh detection resistor is connected to the sixth switch and the power ground; and The twelfth detection resistor is connected to the fifth voltage terminal and the fifth switch.

23. The charging and discharging circuit according to any one of claims 12-22, characterized in that, The wake-up circuit also includes: The second filtering circuit is connected between the second switch and the power ground, and is used to filter interference signals in the wake-up circuit.

24. The charging and discharging circuit according to claim 23, characterized in that, The second filter circuit includes: A second filter resistor, the first terminal of which is connected to the second switch; and The third filter capacitor is connected between the second terminal of the second filter resistor and the power supply ground.

25. A battery management system, characterized in that, include: The charging and discharging circuit as described in any one of claims 1-24.

26. A battery system, characterized in that, include: The battery management system as described in claim 25.

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