Protection circuit, battery module and battery protection method and system

Abstract

The invention provides a protection circuit, a battery module and a battery protection method and system, and the protection circuit comprises an activation module for activating the battery module, a power module for providing a working voltage for the battery module, a single-chip microcomputer for providing a control signal for the battery module, and a charging module for controlling the charging of the battery module. The discharging module is used for controlling the battery module to discharge; and the sampling module is used for monitoring the battery module. The battery module has a protection function, when the energy storage battery is under-voltage, the single chip microcomputer controls the charging module to be started to charge the energy storage battery, and charging is stopped after charging is completed; when an emergency occurs, the energy storage battery discharges the electric equipment through the discharge module so as to realize an emergency power supply function. Meanwhile, information such as charging voltage, battery voltage, discharging current and working temperature is collected through the collection module so as to guarantee that the energy storage battery works in a reasonable state; the safety and the stability of the battery module are greatly improved, and the battery module can be used as a vehicle-mounted standby battery.

Description

Technical Field

[0001] The present invention relates to the field of power supplies, and in particular to a protection circuit, a battery module, a battery protection method and a system. Background Art

[0002] New energy vehicles are an area that all countries in the world today attach great importance to, and are an important driving force for the comprehensive upgrading and transformation of the industrial chain. In order to achieve overtaking in the automotive field, my country has invested a lot of money, manpower, and material resources into the field of new energy vehicles. At present, a large number of excellent new energy vehicle companies have emerged in my country. With the rapid growth of the new energy vehicle market, more and more new energy vehicles are on the road and small probability accidents occur from time to time, leading to serious consequences. In order to monitor the driving status of the vehicle, it is necessary to store and feedback the driving information of the vehicle for background tracking, remote control, accident tracking, and product iteration optimization.

[0003] All the power of new energy vehicles comes from lithium batteries, which can supply power to the on-board lead-acid batteries to meet the needs of some electrical equipment. Since accidents often occur in an instant, a momentary power outage will result in the inability to feedback driving information, so new energy vehicles are usually equipped with backup batteries to prevent the occurrence of momentary power outages. In order to ensure that the backup batteries of new energy vehicles can operate reliably in various environments, nickel-metal hydride batteries are often used as backup batteries. However, the backup batteries used by most manufacturers are not equipped with corresponding protection boards for protection, and there are still safety issues during use (including but not limited to overvoltage, undervoltage, charging overcurrent, discharging overcurrent, and overtemperature).

[0004] Therefore, how to improve the safety and stability of battery (especially vehicle backup battery) use has become one of the problems that technical personnel in this field need to solve urgently.

[0005] It should be noted that the above introduction to the technical background is only for the convenience of providing a clear and complete description of the technical solutions of the present application and for the convenience of understanding by those skilled in the art. It cannot be considered that the above technical solutions are well known to those skilled in the art simply because they are described in the background technology section of the present application. Summary of the invention

[0006] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a protection circuit, a battery module, a battery protection method and a system for solving the problems of poor safety and stability of battery use in the prior art.

[0007] To achieve the above-mentioned object and other related objects, the present invention provides a protection circuit, which at least includes:

[0008] Activation module, power module, single chip microcomputer, charging module, discharging module and sampling module; wherein,

[0009] The activation module includes a first activation unit, a second activation unit and a third activation unit; the first activation unit is connected to the power supply interface of the battery module, and supplies power to the power module based on an external power supply and provides an enable signal when the battery module is powered on for the first time; the second activation unit is connected to the external activation interface, and generates an enable signal for the power module based on an external activation instruction; the third activation unit receives a self-locking signal provided by the single-chip microcomputer, and generates an enable signal for the power module based on the self-locking signal;

[0010] The power module is connected to the output end of the activation module and the positive electrode of the energy storage battery, and generates the working voltage of the protection circuit when the enable signal is valid and the power module receives electric energy;

[0011] The input end of the charging module is connected to the power supply interface, and the output end is connected to the positive electrode of the energy storage battery, so as to charge the energy storage battery based on the external power supply;

[0012] The input end of the discharge module is connected to the positive electrode of the energy storage battery, and the output end is connected to the discharge interface, so as to provide the electric energy of the energy storage battery to the external electric device;

[0013] The sampling module is connected to the charging module and the discharging module to sample the charging voltage and the discharging current;

[0014] The single chip microcomputer is connected to the activation module, the power module, the charging module, the discharging module and the sampling module, obtains electric energy from the power module, and generates a control signal of the protection circuit based on a sampling signal output by the sampling module.

[0015] Optionally, the activation module includes first, second, third, fourth, and fifth diodes, a PNP transistor, and first, second, third, fourth, and fifth resistors;

[0016] The anode of the first diode is connected to the charging voltage, and the cathode is connected to the ground via the first resistor and the second resistor in sequence; the connection node of the first resistor and the second resistor is connected to the enable terminal of the power module;

[0017] The anode of the second diode is connected to the charging voltage, and the cathode is connected to the power supply terminal of the power module;

[0018] The emitter of the PNP transistor is connected to the positive electrode of the energy storage battery, and the collector is connected to the anode of the third diode; the cathode of the third diode is connected to the cathode of the first diode;

[0019] The third resistor is connected between the emitter and the base of the PNP transistor; the cathode of the fourth diode is connected to the external activation interface, and the anode is connected to the base of the PNP transistor via the fourth resistor;

[0020] An anode of the fifth diode is connected to the self-locking signal, and a cathode is connected to the enable terminal of the power module via the fifth resistor.

[0021] Optionally, the charging module includes sixth and seventh diodes, eighth and ninth resistors, and first and second switch tubes;

[0022] The anode of the sixth diode is connected to the power supply interface, and the cathode outputs the charging voltage and is connected to the anode of the seventh diode via the first switch tube; the cathode of the seventh diode is connected to the positive electrode of the energy storage battery;

[0023] The sixth resistor is connected between the cathode of the sixth diode and the control end of the first switch tube; one end of the second switch tube is grounded, and the other end is connected to the control end of the first switch tube via the seventh resistor;

[0024] One end of the eighth resistor receives a charging control signal, and the other end is connected to the control end of the second switch tube; the ninth resistor is connected between the control end of the second switch tube and a reference ground.

[0025] Optionally, the discharge module includes an eighth diode, a twelfth and thirteenth resistors, and a third and fourth switch tubes;

[0026] One end of the third switch tube is connected to the positive electrode of the energy storage battery, and the other end is connected to the anode of the eighth diode; the cathode of the eighth diode is connected to the discharge interface;

[0027] One end of the tenth resistor is connected to the positive electrode of the energy storage battery, and the other end is connected to the control end of the third switch tube; one end of the fourth switch tube is grounded, and the other end is connected to the control end of the third switch tube via the eleventh resistor;

[0028] One end of the twelfth resistor receives a discharge control signal, and the other end is connected to the control end of the fourth switch tube; the thirteenth resistor is connected between the control end of the fourth switch tube and a reference ground.

[0029] Optionally, the sampling module further samples any one or more of the battery voltage, the operating temperature and the external activation instruction.

[0030] To achieve the above-mentioned object and other related objects, the present invention also provides a battery module, which at least includes: an energy storage battery and the above-mentioned protection circuit; the protection circuit is connected to the energy storage battery for protecting the energy storage battery.

[0031] In order to achieve the above-mentioned object and other related objects, the present invention further provides a battery protection method, which is implemented based on the above-mentioned battery module, and the battery protection method at least includes:

[0032] Activating the battery module, the battery module generates an operating voltage inside and enters a working state;

[0033] When the energy storage battery in the battery module is low on power, an external power supply charges the energy storage battery and monitors the charging voltage to perform charging control;

[0034] When the power-consuming device connected to the battery module is powered off, the energy storage battery discharges to supply power to the power-consuming device and monitors the discharge current to perform discharge control.

[0035] Optionally, the method for activating the battery module includes:

[0036] Activation mode 1: When the battery module is powered on for the first time, the protection circuit is activated, and the battery module enters the working state from the dormant state;

[0037] Activation mode 2: When the battery module receives an external activation command and the protection circuit receives electric energy, the protection circuit is activated and the battery module enters the working state from the dormant state;

[0038] Activation method three: when the external power supply is powered off and the battery module cannot receive an external activation command, the energy storage battery supplies power to the protection circuit, the single-chip microcomputer provides a self-locking signal, and the protection circuit is activated.

[0039] More optionally, the priorities of activation mode 1, activation mode 2, and activation mode 3 decrease in sequence.

[0040] In order to achieve the above-mentioned object and other related objects, the present invention further provides a battery protection system, which at least comprises:

[0041] Lead-acid battery, electrical equipment and the above-mentioned battery module, wherein the battery module is used as a backup battery;

[0042] The lead-acid battery is connected to the battery module and the electrical equipment to provide electrical energy to the battery module and the electrical equipment;

[0043] The battery module is connected to the electrical equipment to provide electrical energy to the electrical equipment.

[0044] Optionally, the electrical equipment is a new energy vehicle; the power supply system also includes a power battery, and the power battery is connected to the lead-acid battery and the electrical equipment to provide electrical energy to the lead-acid battery and the electrical equipment.

[0045] As described above, the protection circuit, battery module, battery protection method and system of the present invention have the following beneficial effects:

[0046] 1. The battery module of the present invention has a protection function. When the energy storage battery is undervoltage, the single chip microcomputer controls the charging module to start charging the energy storage battery, and turns off the charging when the charging is completed; when an emergency occurs, the energy storage battery discharges to the electrical equipment through the discharge module to realize the emergency power supply function; at the same time, the collection module collects information such as charging voltage, battery voltage, discharge current, working temperature, etc. to ensure that the energy storage battery works in a reasonable state; the safety and stability are greatly improved.

[0047] 2. The battery module of the present invention can be used as a vehicle-mounted backup battery, which can not only meet the emergency power supply to the load in the event of a sudden power outage, but also protect the backup battery to ensure that its charging and discharging voltage, charging and discharging current, temperature, etc. operate within a reasonable design range. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 Shown is a schematic structural diagram of the protection circuit and battery module of the present invention.

[0049] Figure 2 Shown is a schematic structural diagram of the protection circuit of the present invention.

[0050] Figure 3 Shown is a structural schematic diagram of the power supply system of the present invention.

[0051] Component number description

[0052] 1 Battery module

[0053] 11. Protection Circuit

[0054] 111 Activate module

[0055] 112 Power Module

[0056] 112a Switching Power Supply

[0057] 113 Charging module

[0058] 113a Adjustable constant current source unit

[0059] 114 Discharge module

[0060] 115 Sampling Module

[0061] 115a Charging voltage sampling unit

[0062] 115b Discharge current sampling unit

[0063] 115c Battery voltage sampling unit

[0064] 115d Working temperature sampling unit

[0065] 115e External Excitation Sampling Unit

[0066] 116 MCU

[0067] 12 Energy Storage Batteries

[0068] 2 Lead-acid batteries

[0069] 3 Electrical equipment

[0070] 4 Power battery DETAILED DESCRIPTION

[0071] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0072] See also Figure 1 to Figure 3 It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner, and the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0073] like Figure 1 As shown, the present invention provides a protection circuit 11, and the protection circuit 11 includes:

[0074] An activation module 111 , a power module 112 , a charging module 113 , a discharging module 114 , a sampling module 115 and a single chip microcomputer 116 .

[0075] like Figure 2As shown, the activation module 11 includes a first activation unit, a second activation unit and a third activation unit. The first activation unit is connected to the power supply interface CHG+ of the battery module 1, and supplies power to the power module 112 based on an external power supply and provides an enable signal EN when the battery module 11 is powered on for the first time; the second activation unit is connected to the external activation interface AC, and generates an enable signal EN for the power module 112 based on an external activation instruction; the third activation unit receives the self-locking signal 3V3_EN provided by the single-chip microcomputer 116, and generates an enable signal EN for the power module 112 based on the self-locking signal 3V3_EN.

[0076] Specifically, in this embodiment, the first activation unit, the second activation unit, and some components of the second activation unit are shared. In actual use, each activation unit can be set completely independently, and all circuit structures that can achieve the above functions are applicable. Figure 2 As shown, as an example, the activation module 111 includes a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, a fifth diode D5, a PNP transistor Q, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4 and a fifth resistor R5. The anode of the first diode D1 is connected to the charging voltage V-IN, and the cathode is connected to the ground via the first resistor R1 and the second resistor R2 in sequence; the connection node of the first resistor R1 and the second resistor R2 is connected to the enable end of the power module 112; the anode of the second diode D2 is connected to the charging voltage V-IN, and the cathode is connected to the power end of the power module 112; the emitter of the PNP transistor Q is connected to the positive electrode B+ of the energy storage battery, and the collector is connected to the anode of the third diode D3; the cathode of the third diode D3 is connected to the cathode of the first diode D1; the third resistor R3 is connected between the emitter and the base of the PNP transistor Q; the cathode of the fourth diode D4 is connected to the external activation interface AC, and the anode is connected to the base of the PNP transistor Q via the fourth resistor R4; the anode of the fifth diode D5 is connected to the self-locking signal 3V3_EN, and the cathode is connected to the enable end of the power module 112 via the fifth resistor R5.

[0077] The examples provided in this embodiment are only for a better understanding of the present invention. In actual use, any circuit structure that can realize the above functions is applicable to the present invention, and is not limited to this embodiment.

[0078] like Figure 2 As shown, the power module 112 is connected to the output end of the activation module 111 and the positive electrode B+ of the energy storage battery, and generates the working voltage of the protection circuit when the enable signal EN is valid and the power module 112 receives electric energy.

[0079] Specifically, in this embodiment, the power module 112 includes a switching power supply 112a and peripheral devices (a ninth diode D9 and a fourteenth resistor R14). The enable terminal EN of the switching power supply 112a serves as the enable terminal of the power module 112, and the power terminal VCC of the switching power supply 112 is connected to the cathode of the ninth diode D9 via the fourteenth resistor R14; the anode of the ninth diode D9 is connected to the positive electrode B+ of the energy storage battery. The output terminal OUT of the switching power supply 112a outputs the operating voltage. In this example, the operating voltage is set to 3.3V.

[0080] The examples provided in this embodiment are only for a better understanding of the present invention. In actual use, any circuit structure that can realize the above functions is applicable to the present invention, and is not limited to this embodiment.

[0081] like Figure 2 As shown, the input end of the charging module 113 is connected to the power supply interface CHG+, and the output end is connected to the positive electrode B+ of the energy storage battery, and the energy storage battery 12 is charged based on the external power supply.

[0082] Specifically, in this embodiment, the charging module 113 includes a sixth diode D6, a seventh diode D7, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a first switch tube T1 and a second switch tube T2. The anode of the sixth diode D6 is connected to the power supply interface CHG+, and the cathode outputs the charging voltage V-IN and is connected to the anode of the seventh diode D7 via the first switch tube T1; the cathode of the seventh diode D7 is connected to the positive electrode B+ of the energy storage battery; the sixth resistor R6 is connected between the cathode of the sixth diode D6 and the control end of the first switch tube T1; one end of the second switch tube T2 is grounded, and the other end is connected to the control end of the first switch tube T1 via the seventh resistor R7; one end of the eighth resistor R8 receives the charging control signal MCU_CHG, and the other end is connected to the control end of the second switch tube T2; the ninth resistor R9 is connected between the control end of the second switch tube T2 and the reference ground. As another implementation of the present invention, an adjustable constant current source unit 113a is further connected in series between the first switch tube T1 and the seventh diode D7 to achieve constant current charging.

[0083] The examples provided in this embodiment are only for a better understanding of the present invention. In actual use, any circuit structure that can achieve the above functions is applicable to the present invention, including but not limited to increasing output power, charging temperature control and other changes, which will not be described one by one here.

[0084] like Figure 2As shown, the input end of the discharge module 114 is connected to the positive electrode B+ of the energy storage battery, and the output end is connected to the discharge interface DHG, which is used to provide the electric energy of the energy storage battery 12 to external electrical equipment.

[0085] Specifically, in this embodiment, the discharge module 114 includes an eighth diode D8, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a third switch tube T3 and a fourth switch tube T4. One end of the third switch tube T3 is connected to the positive electrode B+ of the energy storage battery, and the other end is connected to the anode of the eighth diode D8; the cathode of the eighth diode D8 is connected to the discharge interface DHG; one end of the tenth resistor R10 is connected to the positive electrode B+ of the energy storage battery, and the other end is connected to the control end of the third switch tube T3; one end of the fourth switch tube T4 is grounded, and the other end is connected to the control end of the third switch tube T3 via the eleventh resistor R11; one end of the twelfth resistor R12 receives the discharge control signal MCU_DSG, and the other end is connected to the control end of the fourth switch tube T4; the thirteenth resistor R13 is connected between the control end of the fourth switch tube T4 and the reference ground.

[0086] The examples provided in this embodiment are only for a better understanding of the present invention. In actual use, any circuit structure that can achieve the above functions is applicable to the present invention, including but not limited to replacement by multi-stage amplifier circuits and integrated modules to achieve richer over-current, over-temperature, high-power and other changes, which will not be elaborated here.

[0087] like Figure 2 As shown, the sampling module 115 is connected to the charging module 113 and the discharging module 114 to sample the charging voltage and the discharging current.

[0088] Specifically, in this embodiment, the sampling module 115 includes a charging voltage sampling unit 115a and a discharging current sampling unit 115b. The charging voltage sampling unit 115a includes a fifteenth resistor R15 and a sixteenth resistor R16, the fifteenth resistor R15 and the sixteenth resistor R16 are connected in series between the charging voltage V-IN and the reference ground, and the connection node between the fifteenth resistor R15 and the sixteenth resistor R16 outputs a charging voltage sampling signal V-IN_MCU. The discharging current sampling unit 115b includes a seventeenth resistor R17 and an eighteenth resistor R18, the seventeenth resistor R17 and the eighteenth resistor R18 are connected in series between the anode of the ninth diode D9 and the reference ground, and the connection node between the seventeenth resistor R17 and the eighteenth resistor R18 outputs a discharging current sampling signal DI_MCU.

[0089] Specifically, as another implementation of the present invention, the sampling module 115 further includes a battery voltage sampling unit 115c, an operating temperature sampling unit 115d, and an external excitation sampling unit 115e. The battery voltage sampling unit 115c includes a nineteenth resistor R19, a twentieth resistor R20, a twenty-first resistor R21, a twenty-second resistor R22, and a fifth switch tube T5; one end of the nineteenth resistor R19 is connected to the positive electrode B+ of the energy storage battery, and the other end is grounded via the fifth switch tube T5 and the twenty-third resistor R20 in sequence; one end of the twenty-first resistor R21 receives the battery voltage acquisition control signal MCU_B+, and the other end is connected to the control end of the fifth switch tube T5; one end of the twenty-second resistor R22 is connected to the control end of the fifth switch tube T5, and the other end is grounded; the connection node between the fifth switch tube T5 and the twenty-third resistor R20 outputs the battery voltage sampling signal B+_MCU. The working temperature sampling unit 115d includes a twenty-third resistor R23, a thermistor RT and a twenty-fourth resistor R24; one end of the twenty-third resistor R23 receives the working voltage, and the other end is grounded via the thermistor RT; one end of the twenty-fourth resistor R24 ​​is connected to the connection node of the twenty-third resistor R23 and the thermistor RT, and the other end outputs the working temperature sampling signal NTC_MCU. The external excitation sampling unit 115e includes a twenty-fifth resistor R25 and a twenty-sixth resistor R26, the twenty-fifth resistor R5 and the twenty-sixth resistor R6 are connected in series between the collector of the PNP transistor Q and the reference ground, and the connection node of the twenty-fifth resistor R5 and the twenty-sixth resistor R6 outputs the external activation sampling signal AC_MCU.

[0090] The examples provided in this embodiment are only for a better understanding of the present invention. In actual use, any circuit structure that can achieve the above functions is applicable to the present invention, not limited to this embodiment. The sampling object can be set as needed. The sampling of battery voltage, operating temperature and external excitation signal can be selected one by one, or two or all three items can be selected. In addition, after being familiar with the technical ideas of the present invention, other collection functions can be added according to needs, such as charging current collection, single cell voltage collection, or collecting battery voltage through battery protection IC and achieving balancing, etc., which will not be described one by one here.

[0091] like Figure 2 As shown, the single chip microcomputer 116 is connected to the activation module 111, the power module 112, the charging module 113, the discharging module 114 and the sampling module 115, obtains electric energy from the power module 112, and generates a control signal of the protection circuit 11 based on the sampling signal output by the sampling module 115.

[0092] Specifically, in this embodiment, the single-chip microcomputer 116 receives the working voltage (3.3V), the charging voltage sampling signal V-IN_MCU, the discharging current sampling signal DI_MCU, the battery voltage sampling signal B+_MCU, the working temperature sampling signal NTC_MCU and the external activation sampling signal AC_MCU, and generates the self-locking signal 3V3_EN, the charging control signal MCU_CHG, the discharging control signal MCU_DSG and the battery voltage acquisition control signal MCU_B+. In actual use, the input signal and output signal of the single-chip microcomputer 16 can be set according to specific needs, not limited to this embodiment.

[0093] It should be noted that, in this embodiment, the first switch tube T1 and the third switch tube T3 are implemented by sampling PMOS tubes, and the second switch tube T2, the fourth switch tube T4 and the fifth switch tube T5 are implemented by NMOS tubes; in actual use, any device that can realize the switch function based on the control of the control end can be used, and the control logic is adjusted accordingly, which is not described here one by one. In this embodiment, each diode is used to limit the current flow direction. Figure 2 The thick arrows in the middle indicate the direction of large current charging and discharging, and the thin arrows indicate small current and signal logic relationship diagrams.

[0094] like Figure 1 As shown, the present invention further provides a battery module 1 , which includes: a protection circuit 11 and an energy storage battery 12 .

[0095] like Figure 1 As shown, the energy storage battery 12 serves as an energy storage element in the battery module 1 .

[0096] Specifically, in this embodiment, the energy storage battery 12 is configured as a nickel-hydrogen battery; in actual use, any battery made of any material that can be charged and discharged is applicable, and will not be described in detail here.

[0097] like Figure 1 As shown, the protection circuit 11 is connected to the energy storage battery 12 to protect the energy storage battery 12. The specific structure is as mentioned above and will not be described here one by one.

[0098] like Figure 3 As shown, the present invention also provides a power supply system, the power supply system comprising:

[0099] The battery module 1, the lead-acid battery 2 and the electrical equipment 3, wherein the battery module 1 is used as a backup battery.

[0100] like Figure 3 As shown, the lead-acid battery 2 is connected to the battery module 1 and the electrical equipment 3 to provide electrical energy to the battery module 1 and the electrical equipment 3.

[0101] like Figure 3 As shown, the battery module 1 is connected to the electrical device 3 to provide electrical energy to the electrical device 3 .

[0102] Specifically, when the lead-acid battery 2 is powered, the lead-acid battery 2 supplies power to the power-consuming device 3; when the lead-acid battery 2 is powered off, the battery module 1 is used as a backup battery to supply power to the power-consuming device 3. When the battery module 1 is out of power, the lead-acid battery 2 supplies power to the battery module 1.

[0103] The battery module 1 and the lead-acid battery 2 can be used as independent power supply modules in any power-consuming device 3. In this example, the power-consuming device 3 is a new energy vehicle. The power supply system also includes a power battery 4, which is connected to the lead-acid battery 2 and the power-consuming device 3 to provide power to the lead-acid battery 2 and the power-consuming device 3. When an accident occurs in the vehicle and the power battery 4 and the lead-acid battery 2 are unable to supply power to the power-consuming device 3, the battery module 1 is activated. In this embodiment, the power battery is a lithium battery. In actual use, any storage battery is applicable and will not be described in detail here.

[0104] It should be noted that although the power battery 4, the lead-acid battery 2 and the battery module 1 all supply power to the electrical equipment 3, the specific power supply objects are not exactly the same. As an example, the battery module 1 supplies power to various modules in the electrical equipment 3 that are responsible for data acquisition, storage and communication and require emergency power supply from a backup battery in the event of a sudden power outage, so as to store system information data at the moment of the emergency.

[0105] The battery protection method implemented by the battery module 1 of the present invention is as follows:

[0106] 1) Activate the battery module 1, the battery module 1 generates an operating voltage inside and enters a working state.

[0107] In this embodiment, the power module 112 can output 3.3V voltage only when its enable EN is valid and the VCC terminal is powered, and the activation is successful. There are three activation methods:

[0108] Activation method 1: After the battery module 1 is produced and before it is used, the protection circuit 11 of the battery module 1 is in a dormant state to ensure that the power of the energy storage battery 12 is not consumed during storage and transportation. Therefore, the battery module 1 requires a power-on activation mechanism, that is, when the battery module 1 is powered on for the first time, the protection circuit 11 is activated, and the battery module 1 enters the working state from the dormant state to ensure that the protection system can start and work normally when the finished battery (i.e., the battery module 1) is produced and used.

[0109] Specifically, Figure 2 As shown, in this embodiment, when the finished battery is connected to an electrical device (including but not limited to a vehicle electrical system), the external power supply supplies power to the switching power supply 112a through the sixth diode D6, the second diode D2 and the fourteenth resistor R14; at the same time, the external power supply provides an enable signal EN to the switching power supply 112a through the sixth diode D6, and then after voltage division by the first resistor R1 and the second resistor R2. Therefore, after the first power-on, the switching power supply 112a can output a 3.3V working voltage to activate the protection circuit 11.

[0110] Activation method 2: After the protection circuit 11 is enabled, when the power-consuming device 3 is not working (including but not limited to when the vehicle is parked), the protection circuit 11 is required to be in a dormant state to reduce power consumption. When the power-consuming device 3 is working again (including but not limited to when the vehicle is started), the protection circuit 11 needs to be activated again. Therefore, the battery module 1 needs to activate the protection circuit 11 according to an external activation instruction, that is, when the battery module 1 receives an external activation instruction and the protection circuit 11 receives the electric energy provided by the energy storage battery 12, the protection circuit 11 is activated, and the battery module 1 enters the working state from the dormant state.

[0111] Specifically, Figure 2 As shown, in this embodiment, the protection circuit 11 is in a dormant state when the vehicle is parked, and the protection circuit 12 needs to be in an activated state during the vehicle startup and driving process to cope with the situation that emergency power supply may occur at any time. In some cases, the vehicle control system will turn off the charging switch (the first switch tube T1) of the power supply interface CHG+, or when the power supply interface CHG+ cannot supply power when a fault occurs, the key switch provides an external activation command AC to maintain the protection circuit 11 in an activated state. When the vehicle is started or driving, the external activation command AC is at a low level, and the voltage on the energy storage battery 12 (B+ terminal voltage) is divided by the third resistor R3 and the fourth resistor R4 to provide a bias voltage for the PNP transistor Q. After the PNP transistor Q is turned on and passes through the third diode D3, it is divided by the first resistor R1 and the second resistor R2 to provide an enable signal EN for the switching power supply 112a. At the same time, the energy storage battery 12 supplies power to the switching power supply 112a through the ninth diode D9 and the fourteenth resistor R14. Therefore, the switching power supply 112a obtains the EN enable signal EN and the power supply VCC, and then outputs a 3.3V working voltage, and the protection circuit 11 is activated.

[0112] Activation method three: After the protection circuit 11 is enabled, it is necessary to control the working voltage to work for a long time to cope with the emergency power supply in case of power failure at any time. Therefore, the protection circuit 11 forms an interlocking function with the internal working voltage after being connected to the vehicle. When the external power supply suddenly loses power, the protection circuit 11 is required to continue working, and the battery module 1 serves as a backup battery to provide energy to the power module 112 to maintain a stable output of 3.3V power. That is, when the external power supply loses power and the battery module 1 cannot receive an external activation command, the energy storage battery 12 supplies power to the protection circuit 11, the single-chip computer 116 provides a self-locking signal, and the protection circuit 11 is activated.

[0113] Specifically, in this embodiment, after the vehicle is started, the protection circuit 11 is in an activated state. When an emergency situation causes the failure to provide external power supply and external activation command AC, the energy storage battery 12 supplies power to the switching power supply 112a through the ninth diode D9 and the fourteenth resistor R14, and the single-chip computer 116 provides a high-level self-locking signal 3V3_EN, and provides an enable signal EN to the switching power supply 112a after passing through the fifth resistor R5. Therefore, the switching power supply 112a obtains the EN enable signal EN and the power supply VCC, and then outputs a 3.3V working voltage, and the protection circuit 11 is activated.

[0114] It should be noted that in order to extend the battery life and ensure that it is always in a charged state, the number of charge and discharge times should be minimized. Therefore, the three activation methods have primary and secondary levels, and the competitive power-on method is used to maintain the activation state. In this example, the priorities of activation method one, activation method two, and activation method three are reduced in sequence, that is, the first level is maintained by the lead-acid battery through the charging interface when it is first powered on, the second level is maintained by an external activation instruction, and the third level is maintained by the battery module 1 itself. The activation method level can also be adjusted according to actual needs, not limited to this embodiment. In this embodiment, only three competitive power-on activation methods are shown. Expanding more activation methods according to actual needs is also within the technical concept described in the present invention and also belongs to the scope of protection of the patent right of the present invention.

[0115] 2) When the energy storage battery 12 in the battery module 1 is low on power, an external power supply charges the energy storage battery 12 and monitors the charging voltage to perform charging control.

[0116] Specifically, in this embodiment, the external power supply is provided by a lead-acid battery, which is input from the power supply interface CHG+, and is input to the source of the first switch tube T1 after passing through the sixth diode D6. The on and off states of the first switch tube T1 are controlled by the charging control signal MCU_CHG. When the charging control signal MCU_CHG is at a low level, the second switch tube T2 is closed without a driving signal, the sixth resistor R6 and the seventh resistor R7 have no voltage division effect, and the first switch tube T1 is closed without a bias driving signal, and charging is prohibited. When the single-chip computer 116 finds that the voltage of the energy storage battery 12 is too low, the charging control signal MCU_CHG is output as a high level, which is input to the base of the second switch tube T2 through the eighth resistor R8, and the base of the second switch tube T2 obtains the driving signal to turn on, wherein the ninth resistor R9 plays the role of voltage division and fixed level. The second switch tube T2 obtains the driving signal to turn on, and the sixth resistor R6 and the seventh resistor R7 divide the voltage to provide a driving bias voltage for the first switch tube T1, and the first switch tube T1 is turned on. The first switch tube T1 outputs the charging current to the adjustable constant current source unit 113a to realize the constant current charging function. The output of the adjustable constant current source unit 113a is input to the positive electrode B+ of the energy storage battery after passing through the seventh diode D7 to charge the energy storage battery 12.

[0117] 3) When the power-consuming device 3 connected to the battery module 1 is powered off, the energy storage battery 12 discharges to supply power to the power-consuming device 3 and monitors the discharge current to perform discharge control.

[0118] Specifically, in this embodiment, when the discharge control signal MCU_DSG output by the single chip microcomputer 116 is at a low level, the fourth switch tube T4 is closed without a driving signal, the tenth resistor R10 and the eleventh resistor R11 have no voltage division effect, and the third switch tube T3 is turned off without a bias driving signal and cannot discharge. When the discharge control signal MCU_DSG output by the single chip microcomputer 116 is at a high level, after the voltage is divided by the twelfth resistor R12 and the thirteenth resistor R13, the base of the fourth switch tube T4 obtains a driving signal to turn on, and the positive electrode B+ voltage of the energy storage battery is divided by the tenth resistor 10 and the eleventh resistor 11 to provide a driving bias voltage for the third switch tube T3, and the third switch tube T3 is turned on, and the output of the third switch tube T3 is output to the discharge interface DHG after passing through the eighth diode D8 to power the external power device 3.

[0119] The protection method of the present invention also includes a sampling step to achieve overvoltage, undervoltage, charging overcurrent, discharging overcurrent, and overtemperature protection.

[0120] Charging voltage sampling: Specifically, Figure 2As shown, the fifteenth resistor R15 and the sixteenth resistor R16 divide the charging voltage V-IN to obtain a divided voltage signal V-IN_MCU (i.e., a charging voltage sampling signal). The charging voltage sampling signal V-IN_MCU is input to the single-chip microcomputer 116. When the single-chip microcomputer 116 determines that the charging voltage sampling signal V-IN_MCU is not within the normal range, it is considered that the lead-acid battery does not provide a charging voltage or other faults occur. The single-chip microcomputer 116 starts a charging protection mechanism, and the charging control signal MCU_CHG is at a low level, prohibiting charging.

[0121] Discharge current sampling: the nineteenth resistor R17 and the eighteenth resistor R18 divide the positive voltage of the eighth diode D8 to obtain a divided voltage signal DI_MCU (i.e., a discharge current sampling signal). The discharge current sampling signal DI_MCU is input to the single-chip microcomputer 116. When the single-chip microcomputer 116 determines that the discharge current sampling signal DI_MCU is not within the normal range, it is considered that a discharge overcurrent or other discharge fault occurs, and the discharge protection mechanism is started. The discharge control signal MCU_DSG is low, and discharge is prohibited.

[0122] Battery voltage sampling: When the battery voltage acquisition control signal MCU_B+ is at a low level, the fifth switch tube T5 is turned off without a driving signal, and the battery voltage acquisition function is turned off. When the battery voltage acquisition control signal MCU_B+ is at a high level, the fifth switch tube T5 obtains a driving signal and turns on after voltage division by the twenty-first resistor R21 and the twenty-second resistor R22, and the voltage B+ on the energy storage battery 12 is divided by the nineteenth resistor R19 and the twenty-third resistor R20 to obtain a signal B+_MCU (i.e., a battery voltage sampling signal), and the battery voltage sampling signal B+_MCU is input to the single-chip microcomputer 116. When the single-chip microcomputer 116 determines that the battery voltage sampling signal B+_MCU is too high, it is considered that the energy storage battery 12 is over-voltage, and the charging function will be turned off; when the single-chip microcomputer 116 determines that the battery voltage sampling signal B+_MCU is too low, it is considered that the energy storage battery 12 is under-voltage, and the discharge function will be turned off to control power consumption.

[0123] Working temperature sampling: When the temperature of the energy storage battery 12 changes, the resistance of the thermistor RT also changes, so the voltage division value of the twenty-third resistor R23 and the thermistor RT changes. The voltage division value passes through the twenty-fourth resistor R24 ​​to obtain a signal NTC_MCU (i.e., a temperature sampling signal). The temperature sampling signal NTC_MCU is input to the single-chip microcomputer 116. When the single-chip microcomputer 116 determines that the temperature sampling signal NTC_MCU is in an abnormal range, it is determined that the temperature of the energy storage battery 12 is abnormal, and the charging and discharging functions are turned off.

[0124] In summary, the present invention provides a protection circuit, a battery module, a battery protection method and a system, comprising: an activation module, a power module, a single-chip microcomputer, a charging module, a discharging module and a sampling module; wherein the activation module comprises a first activation unit, a second activation unit and a third activation unit; the first activation unit is connected to the power supply interface of the battery module, and supplies power to the power module based on an external power supply and provides an enable signal when the battery module is powered on for the first time; the second activation unit is connected to the external activation interface, and generates an enable signal for the power module based on an external activation instruction; the third activation unit receives a self-locking signal provided by the single-chip microcomputer, and generates an enable signal for the power module based on the self-locking signal; the power module is connected to the output end of the activation module and the positive electrode of the energy storage battery, The operating voltage of the protection circuit is generated when the enable signal is valid and the power module receives electric energy; the input end of the charging module is connected to the power supply interface, and the output end is connected to the positive electrode of the energy storage battery, and the energy storage battery is charged based on the external power supply; the input end of the discharge module is connected to the positive electrode of the energy storage battery, and the output end is connected to the discharge interface, and is used to provide the electric energy of the energy storage battery to external electrical equipment; the sampling module is connected to the charging module and the discharge module, and samples the charging voltage and the discharge current; the single-chip computer is connected to the activation module, the power module, the charging module, the discharge module and the sampling module, obtains electric energy from the power module, and generates the control signal of the protection circuit based on the sampling signal output by the sampling module. The battery module of the present invention has a protection function. When the energy storage battery is undervoltage, the single-chip microcomputer controls the charging module to start charging the energy storage battery, and the charging is turned off after the charging is completed. When an emergency occurs, the energy storage battery discharges to the electrical equipment through the discharge module to realize the emergency power supply function. At the same time, the collection module collects information such as charging voltage, battery voltage, discharge current, and operating temperature to ensure that the energy storage battery works in a reasonable state; the safety and stability are greatly improved. The battery module of the present invention can be used as a vehicle-mounted backup battery, which can not only meet the emergency power supply to the load in the event of a sudden power outage, but also protect the backup battery to ensure that its charging and discharging voltage, charging and discharging current, temperature, etc. work within a reasonable design range. Therefore, the present invention effectively overcomes the various shortcomings in the prior art and has a high industrial utilization value.

[0125] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A protection circuit, characterized in that: The protection circuit at least comprises: Activation module, power module, single chip microcomputer, charging module, discharging module and sampling module; wherein, The activation module includes a first activation unit, a second activation unit and a third activation unit; the first activation unit is connected to the power supply interface of the battery module, and supplies power to the power module based on an external power supply and provides an enable signal when the battery module is powered on for the first time; the second activation unit is connected to the external activation interface, and generates an enable signal for the power module based on an external activation instruction; the third activation unit receives a self-locking signal provided by the single-chip microcomputer, and generates an enable signal for the power module based on the self-locking signal; The power module is connected to the output end of the activation module and the positive electrode of the energy storage battery, and generates the working voltage of the protection circuit when the enable signal is valid and the power module receives electric energy; The input end of the charging module is connected to the power supply interface, and the output end is connected to the positive electrode of the energy storage battery, so as to charge the energy storage battery based on the external power supply; The input end of the discharge module is connected to the positive electrode of the energy storage battery, and the output end is connected to the discharge interface, so as to provide the electric energy of the energy storage battery to the external electric device; The sampling module is connected to the charging module and the discharging module to sample the charging voltage and the discharging current; The single chip microcomputer is connected to the activation module, the power module, the charging module, the discharging module and the sampling module, obtains electric energy from the power module, and generates a control signal of the protection circuit based on a sampling signal output by the sampling module.

2. The protection circuit according to claim 1, characterized in that: The activation module includes first, second, third, fourth and fifth diodes, a PNP transistor, and first, second, third, fourth and fifth resistors; The anode of the first diode is connected to the charging voltage, and the cathode is connected to the ground via the first resistor and the second resistor in sequence; the connection node of the first resistor and the second resistor is connected to the enable terminal of the power module; The anode of the second diode is connected to the charging voltage, and the cathode is connected to the power supply terminal of the power module; The emitter of the PNP transistor is connected to the positive electrode of the energy storage battery, and the collector is connected to the anode of the third diode; the cathode of the third diode is connected to the cathode of the first diode; The third resistor is connected between the emitter and the base of the PNP transistor; the cathode of the fourth diode is connected to the external activation interface, and the anode is connected to the base of the PNP transistor via the fourth resistor; An anode of the fifth diode is connected to the self-locking signal, and a cathode is connected to the enable terminal of the power module via the fifth resistor.

3. The protection circuit according to claim 1, characterized in that: The charging module includes sixth and seventh diodes, eighth and ninth resistors, and first and second switch tubes; The anode of the sixth diode is connected to the power supply interface, and the cathode outputs the charging voltage and is connected to the anode of the seventh diode via the first switch tube; the cathode of the seventh diode is connected to the positive electrode of the energy storage battery; The sixth resistor is connected between the cathode of the sixth diode and the control end of the first switch tube; one end of the second switch tube is grounded, and the other end is connected to the control end of the first switch tube via the seventh resistor; One end of the eighth resistor receives a charging control signal, and the other end is connected to the control end of the second switch tube; the ninth resistor is connected between the control end of the second switch tube and a reference ground.

4. The protection circuit according to claim 1, characterized in that: The discharge module includes an eighth diode, a twelfth and thirteenth resistors, and a third and fourth switch tubes; One end of the third switch tube is connected to the positive electrode of the energy storage battery, and the other end is connected to the anode of the eighth diode; the cathode of the eighth diode is connected to the discharge interface; One end of the tenth resistor is connected to the positive electrode of the energy storage battery, and the other end is connected to the control end of the third switch tube; one end of the fourth switch tube is grounded, and the other end is connected to the control end of the third switch tube via the eleventh resistor; One end of the twelfth resistor receives a discharge control signal, and the other end is connected to the control end of the fourth switch tube; the thirteenth resistor is connected between the control end of the fourth switch tube and a reference ground.

5. The protection circuit according to claim 1, characterized in that: The sampling module also samples any one or more of the battery voltage, the operating temperature and the external activation instruction.

6. A battery module, characterized in that: The battery module at least includes: an energy storage battery and a protection circuit as described in any one of claims 1 to 5; the protection circuit is connected to the energy storage battery for protecting the energy storage battery.

7. A battery protection method, implemented based on the battery module according to any one of claims 1 to 6, characterized in that: The battery protection method at least comprises: Activating the battery module, the battery module generates an operating voltage inside and enters a working state; When the energy storage battery in the battery module is low on power, an external power supply charges the energy storage battery and monitors the charging voltage to perform charging control; When the power-consuming device connected to the battery module is powered off, the energy storage battery discharges to supply power to the power-consuming device and monitors the discharge current to perform discharge control.

8. The battery protection method according to claim 7, characterized in that: The method for activating the battery module includes: Activation mode 1: When the battery module is powered on for the first time, the protection circuit is activated, and the battery module enters the working state from the dormant state; Activation mode 2: When the battery module receives an external activation command and the protection circuit receives electric energy, the protection circuit is activated and the battery module enters the working state from the dormant state; Activation method three: when the external power supply is powered off and the battery module cannot receive an external activation command, the energy storage battery supplies power to the protection circuit, the single-chip microcomputer provides a self-locking signal, and the protection circuit is activated.

9. The battery protection method according to claim 8, characterized in that: The priorities of activation method 1, activation method 2, and activation method 3 decrease in sequence.

10. A battery protection system, characterized in that: The battery protection system at least comprises: A lead-acid battery, an electrical device, and a battery module as claimed in any one of claims 1 to 6, wherein the battery module is used as a backup battery; The lead-acid battery is connected to the battery module and the electrical equipment to provide electrical energy to the battery module and the electrical equipment; The battery module is connected to the electrical equipment to provide electrical energy to the electrical equipment.

11. The battery protection system according to claim 10, characterized in that: The electrical equipment is a new energy vehicle; the power supply system also includes a power battery, which is connected to the lead-acid battery and the electrical equipment to provide electrical energy to the lead-acid battery and the electrical equipment.

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