Battery management device and battery system

Abstract

The invention discloses a battery management device and a battery system. The battery management device comprises a main control module, a battery management module, a DC / DC conversion module, a first acquisition module and a DC / DC auxiliary power supply module. The first acquisition module acquires transmission current between the DC / DC conversion module and the input / output interface; the main control module transmits a first control signal when the transmission current is smaller than a first current threshold value, the main control module transmits a second control signal when the transmission current is larger than a second current threshold value, and the DC / DC auxiliary power supply module responds to the first control signal to enable the DC / DC conversion module to work in a standby mode; the second control signal is responded to enable the DC / DC conversion module to work in a normal working mode, and the DC / DC conversion module responds to a third control signal provided by the main control module in the normal working mode and executes corresponding actions. The energy utilization rate of the battery can be improved.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to a battery management device and a battery system. Background Art

[0002] At present, two-wheeled vehicles, three-wheeled vehicles and other models usually use lead-acid batteries as power sources. However, the undervoltage threshold of lead-acid batteries is relatively high. When the lead-acid battery starts to undervoltage, the battery manager cannot be activated, resulting in low battery energy utilization and poor user experience. Therefore, wide-voltage cell batteries with high energy density and low undervoltage threshold are gradually gaining attention, but the battery management devices of such batteries still have the problem of high power consumption, and the battery energy utilization rate still needs to be improved. Wide-voltage cells also need a corresponding wide-voltage battery manager or device to cooperate when they are deeply charged and discharged. Summary of the invention

[0003] The present invention provides a battery management device and a battery system to improve the energy utilization rate of the battery.

[0004] According to one aspect of the present invention, there is provided a battery management device, comprising:

[0005] Main control module;

[0006] A battery management module, connected to the battery pack and the main control module respectively;

[0007] A DC / DC conversion module, connected to the battery management module, the input and output interfaces of the battery management device and the main control module respectively; the input and output interfaces are used to connect to a load or a charger;

[0008] A first acquisition module, connected to the main control module, for acquiring the transmission current between the DC / DC conversion module and the input / output interface, and providing the current to the main control module;

[0009] A DC / DC auxiliary power supply module is respectively connected to the battery management module, the main control module and the DC / DC conversion module; the battery management module is used to supply power to the DC / DC auxiliary power supply module; the main control module is used to transmit a first control signal to the DC / DC auxiliary power supply module when the transmission current is less than a first current threshold, and the DC / DC auxiliary power supply module is used to stop outputting a power signal in response to the first control signal, so that the DC / DC conversion module works in a standby mode; and the main control module is used to transmit a second control signal to the DC / DC auxiliary power supply module when the transmission current is greater than a second current threshold, and the DC / DC auxiliary power supply module is used to output the power signal in response to the second control signal, so that the DC / DC conversion module works in a normal working mode, and the DC / DC conversion module is used to respond to a third control signal provided by the main control module in the normal working mode and perform corresponding actions; wherein, the second current threshold is greater than or equal to the first current threshold.

[0010] Optionally, when the DC / DC conversion module operates in the standby mode, if the transmission current is greater than the second current threshold, the main control module switches from outputting the first control signal to outputting the second control signal;

[0011] When the DC / DC conversion module operates in the normal working mode, if the transmission current is less than the first current threshold and lasts for a preset time, the main control module switches from outputting the second control signal to outputting the first control signal.

[0012] Optionally, the DC / DC conversion module includes: a DC / DC conversion unit and a DC / DC driving unit;

[0013] The first connection end of the DC / DC conversion unit is connected to the battery management module, the second connection end of the DC / DC conversion unit is connected to the input-output interface, and the control end of the DC / DC conversion unit is connected to the output end of the DC / DC drive unit; wherein the transmission current is the current between the second connection end and the input-output interface;

[0014] The input end of the DC / DC drive unit is connected to the main control module, and the power input end of the DC / DC drive unit is connected to the DC / DC auxiliary power module; the DC / DC drive unit is used to sleep when the power input end does not receive the power signal input, so that the DC / DC conversion module works in the standby mode; and the DC / DC drive unit is used to be awakened when the power input end receives the power signal input, so that the DC / DC conversion module works in the normal working mode; the DC / DC drive unit is used to respond to the third control signal provided by the main control module when awakened, and control the drive signal transmitted to the control end of the DC / DC conversion unit.

[0015] Optionally, the second connection end of the DC / DC conversion unit is connected to the input-output interface via a copper bar;

[0016] The first acquisition module is connected to both ends of the copper bar respectively; the first acquisition module is used to collect the voltage at both ends of the copper bar, and determine the transmission current according to the voltage at both ends of the copper bar.

[0017] Optionally, the battery management module includes:

[0018] A switch unit is connected between the first connection end of the DC / DC conversion unit and the battery pack, and a control end of the switch unit is connected to the main control module;

[0019] A control unit is respectively connected to the battery pack and the main control module; wherein the control unit is used to supply power to the DC / DC auxiliary power supply module, and the control unit is also used to collect the total voltage of the battery pack and transmit it to the main control module; the main control module is also used to generate the third control signal according to the total voltage, and control the on-off state of the switch unit according to the total voltage.

[0020] Optionally, the switch unit includes a charging switch and a discharging switch connected in series between the first connecting end and the battery pack; the control end of the charging switch and the control end of the discharging switch are both connected to the main control module;

[0021] When the input / output interface is connected to the load, the main control module controls the charging switch and the discharging switch to be closed; when the total voltage of the battery pack is less than or equal to the first undervoltage protection threshold of the battery pack, and / or when the voltage of at least one battery in the battery pack is less than the second undervoltage protection threshold of the battery, the main control module controls the third control signal to make the DC / DC drive unit control the DC / DC conversion unit to stop working, and the main control module controls the discharging switch to be disconnected;

[0022] When the input / output interface is connected to the charger, the main control module controls the charging switch to be closed; when the total voltage of the battery pack is greater than the recovery threshold of the battery management module, the main control module controls the discharging switch to be closed, and controls the DC / DC conversion unit not to work; when the total voltage of the battery pack is greater than or equal to the first overvoltage protection threshold of the battery pack, and / or when the voltage of at least one battery in the battery pack is greater than the second overvoltage protection threshold of the battery, the main control module controls the charging switch to be disconnected, and controls the DC / DC conversion unit to stop working;

[0023] Among them, when the input-output interface is connected to the charger and the total voltage of the battery pack is greater than or equal to the recovery working voltage threshold of the DC / DC conversion unit, or when the input-output interface is connected to the load and the transmission current is greater than the second current threshold, the main control module generates the third control signal according to the total voltage of the battery pack and the voltage of the input-output interface.

[0024] Optionally, the battery management module further includes: a current limiting starting unit connected in parallel to both ends of the discharge switch; the current limiting starting unit includes: a current limiting resistor and a switch tube connected in series, and the control electrode of the switch tube is connected to the control unit.

[0025] Optionally, the battery management device also includes: a second acquisition module, connected to the input and output interface and the main control module respectively, for collecting the voltage of the input and output interface and transmitting it to the main control module; the main control module is also used to generate the third control signal according to the voltage of the input and output interface.

[0026] Optionally, the first acquisition module is further used to acquire the voltage and / or temperature of the input / output interface; the second acquisition module is further used to acquire the temperature of the input / output interface and / or the transmission current;

[0027] The main control module is further used to control the third control signal according to at least one of the transmission current, the voltage of the input / output interface, and the temperature of the input / output interface.

[0028] Optionally, the first acquisition module and / or the second acquisition module is further used to acquire the temperature of the input and output interface;

[0029] The main control module is also used to control the transmission current to be within a first current range when the temperature of the input / output interface is within a set temperature range; and to control the transmission current to be within a second current range when the temperature of the input / output interface is outside the set temperature range; wherein the current upper limit value of the first current range is greater than the current upper limit value of the second current range, and both the current upper limit value of the first current range and the current upper limit value of the second current range are greater than the second current threshold.

[0030] Optionally, the battery management device further includes: a state control module; the state control module is connected to the main control module, and the state control module is used to output a state control instruction;

[0031] When the input-output interface is connected to the load, the main control module is used to adjust the third control signal in response to the state control instruction, so that the DC / DC conversion module operates in a working state corresponding to the state control instruction; wherein the DC / DC conversion module provides different voltages and / or currents to the load in different working states.

[0032] Optionally, the batteries in the battery pack include sodium ion batteries, lithium batteries or zinc ion batteries.

[0033] According to another aspect of the present invention, a battery system is provided, including: a battery pack and the battery management device provided by any embodiment of the present invention.

[0034] The technical solution of the embodiment of the present invention is to set a battery management device including a main control module, a battery management module, a DC / DC conversion module, a first acquisition module and a DC / DC auxiliary power supply module. The first acquisition module can collect the transmission current between the DC / DC conversion module and the input and output interface in real time, and then the main control module can output a corresponding control signal according to the size of the transmission current. When the transmission current is less than the first current threshold, it indicates that the battery pack is not currently charging or discharging. The main control module outputs a first control signal, so that the DC / DC auxiliary power supply module responds to the first control signal to stop outputting the power signal, so that the DC / DC conversion module is in standby mode, which can effectively reduce the power consumption of the battery management device. When the transmission current is greater than the second current threshold, it indicates that the battery pack is in a charging or discharging state. The main control module outputs a second control signal, so that the DC / DC auxiliary power supply module responds to the second control signal to output the power signal, so that the DC / DC conversion module is in a normal working mode during the charging and discharging process of the battery pack, and can respond to the third control signal issued by the main control module to adjust the working state, so as to ensure that the battery pack can work normally and stably during the charging and discharging process. In summary, the embodiments of the present invention can reduce the power consumption of the battery management device when the battery pack is not in use, so that the power of the battery pack can be maintained for a longer time, improve the battery energy utilization rate, and thus extend the actual service life of the battery pack.

[0035] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0037] Figure 1 A schematic diagram of the structure of a battery management device provided by an embodiment of the present invention;

[0038] Figure 2 A schematic structural diagram of another battery management device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0039] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0040] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0041] An embodiment of the present invention provides a battery management device. Figure 1 A schematic diagram of a battery management device according to an embodiment of the present invention is provided. Figure 1 The battery management device includes a main control module 10, a battery management module 20, a DC / DC conversion module 30, a first acquisition module 40 and a DC / DC auxiliary power supply module 50.

[0042] The battery management module 20 is connected to the battery pack 200 and the main control module 10 respectively. The DC / DC conversion module 30 is connected to the battery management module 20, the input and output interface 101 of the battery management device and the main control module 10 respectively; the input and output interface 101 is used to connect a load or a charger. The first acquisition module 40 is connected to the main control module 10, and the first acquisition module 40 is used to collect the transmission current between the DC / DC conversion module 30 and the input and output interface 101, and provide it to the main control module 10. The DC / DC auxiliary power supply module 50 is respectively connected to the battery management module 20, the main control module 10 and the DC / DC conversion module 30; the battery management module 20 is used to supply power to the DC / DC auxiliary power supply module 50; the main control module 10 is used to transmit a first control signal to the DC / DC auxiliary power supply module 50 when the transmission current is less than the first current threshold, and the DC / DC auxiliary power supply module 50 is used to stop outputting the power signal in response to the first control signal, so that the DC / DC conversion module 30 works in the standby mode; and the main control module 10 is used to transmit a second control signal to the DC / DC auxiliary power supply module 50 when the transmission current is greater than the second current threshold, and the DC / DC auxiliary power supply module 50 is used to output the power signal in response to the second control signal, so that the DC / DC conversion module 30 works in the normal working mode, and the DC / DC conversion module 30 is used to respond to the third control signal provided by the main control module 10 in the normal working mode and perform corresponding actions; wherein the second current threshold is greater than or equal to the first current threshold.

[0043] It is understandable that when the input-output interface 101 is connected to a load, the transmission current is the discharge current when the battery pack 200 discharges to the load, or is called the load current; when the input-output interface 101 is connected to a charger, the transmission current is the charging current when the charger charges the battery pack 200. In this embodiment, the magnitude of the transmission current is considered to be compared with the first current threshold and the second current threshold, without considering the direction of the transmission current; in other words, the absolute value of the transmission current is compared with the first current threshold and the second current threshold.

[0044] Exemplarily, the battery management device can perform battery management for a battery pack 200 having a wide voltage cell, and the battery pack 200 can be used as a power supply for a vehicle (e.g., a two-wheeled vehicle, a three-wheeled vehicle, etc.). The standby mode can be specifically understood as the DC / DC conversion module 30 only maintaining basic functions and not responding to the instructions of the main control module 10 to operate; the power consumption of the DC / DC conversion module 30 in the standby mode is lower than the power consumption in the normal working mode. Among them, when the battery pack 200 is not discharging / charging, the DC / DC conversion module 30 can be controlled to enter the standby mode, in which case there is basically no discharge current and charging current, so the judgment criterion for this situation is that the transmission current is less than the first current threshold. When the battery pack 200 is discharging or charging, the DC / DC conversion module 30 can be controlled to enter the normal working mode to respond to the control of the main control module 10 to adjust the charging and discharging state of the battery pack 200; therefore, the judgment criterion for this situation is that the transmission current is greater than the second current threshold. In normal working state, the DC / DC conversion module 30 can receive the third control signal output by the main control module 10 to perform corresponding actions, such as controlling the DC / DC conversion module 30 to stop working, perform voltage conversion (such as boost or buck) or be in a direct-on state according to the third control signal. The first current threshold is the threshold current when the DC / DC conversion module 30 enters a low power consumption state, and the second current threshold is the threshold current when the DC / DC conversion module 30 works normally.

[0045] Specifically, the main control module 10 as the core data processing component in the battery management device may include an MCU (Microcontroller Unit). The input and output interface 101 may have a bidirectional function, that is, a voltage stabilizing interface for both charging and discharging.

[0046] The battery management module 20 may include a first connection terminal, a second connection terminal, a communication terminal and an output terminal. The first connection terminal of the battery management module 20 is connected to the battery pack 200, the second connection terminal of the battery management module 20 is connected to the DC / DC conversion module 30, the communication terminal of the battery management module 20 is connected to the main control module 10, and the output terminal of the battery management module 20 is connected to the DC / DC auxiliary power module 50. The battery management module 20 can take power from the battery pack 200, and after voltage conversion, supply power to other functional modules in the battery management device, such as the main control module 10 and the DC / DC auxiliary power module 50. Alternatively, the main control module 10 can also directly take power from the battery pack 200 through the power conversion device configured inside it. In short, the power supply of the electrical components in the battery management module 20 can all come from the battery pack 200. The battery management module 20 can also have the function of real-time acquisition of the total voltage of the battery pack 200, and input the total voltage to the main control module 10, so that the main control module 10 generates a third control signal according to the total voltage, thereby adjusting the working state of the DC / DC conversion module 30.

[0047] The first acquisition module 40 can collect the transmission current between the DC / DC conversion module 30 and the input / output interface 101 in real time, and input the transmission current to the main control module 10. Specifically, the first acquisition module 40 can include a sampling resistor and a detection component, or include a current sensor.

[0048] The DC / DC conversion module 30 may include a first connection terminal, a second connection terminal, a drive control terminal and a power input terminal. The first connection terminal of the DC / DC conversion module 30 is connected to the second connection terminal of the battery management module 20, the second connection terminal of the DC / DC conversion module 30 is connected to the input / output interface 101, the drive control terminal of the DC / DC conversion module 30 is connected to the main control module 10, and the power input terminal of the DC / DC conversion module 30 is connected to the DC / DC auxiliary power module 50. The DC / DC conversion module 30 includes, for example, a voltage conversion component composed of transistors and a driving component for driving each transistor. The power input terminal is, for example, arranged on the driving component. The DC / DC auxiliary power module 50, for example, provides a power signal to the driving component through the power input terminal or stops providing the power signal, so that the driving component sleeps or wakes up, so as to control the DC / DC conversion module 30 as a whole to be in the standby mode or the normal working mode; the drive control terminal is, for example, arranged on the driving component, for receiving the third control signal sent by the main control module 10, and in the normal working mode, drives the voltage conversion component to work according to the third control signal.

[0049] The DC / DC auxiliary power module 50 may include a communication terminal, an input terminal, a first output terminal, and a second output terminal. The communication terminal of the DC / DC auxiliary power module 50 is connected to the main control module 10, the input terminal of the DC / DC auxiliary power module 50 is connected to the output terminal of the battery management module 20, the first output terminal of the DC / DC auxiliary power module 50 is connected to the power input terminal of the DC / DC conversion module 30, and the second output terminal of the DC / DC auxiliary power module 50 is connected to the main control module 10. The DC / DC auxiliary power module 50 may include, for example, a power conversion structure, which is powered by the battery management module 20 and controlled by the main control module 10; for example, the electrical signal provided by the battery management module 20 may be converted into a stable power signal according to the second control signal, the power signal being, for example, a signal with a positive voltage, and the DC / DC conversion module 30 may be powered by the power signal to wake up the DC / DC conversion module 30, and the output of the power signal may be stopped according to the first control signal to make the DC / DC conversion module 30 standby, thereby avoiding energy waste caused by the DC / DC conversion module 30 always being in a normal working state. In addition, the power signal of the DC / DC conversion module 30 is provided by the DC / DC auxiliary power module 50. Even if the power provided by the battery pack 200 or the battery management module 20 is unstable, a stable power signal can be obtained through processing by the DC / DC auxiliary power module 50, thereby avoiding operating mode errors of the DC / DC conversion module 30 due to voltage fluctuations.

[0050] The technical solution of the embodiment of the present invention is to set a battery management device including a main control module 10, a battery management module 20, a DC / DC conversion module 30, a first acquisition module 40 and a DC / DC auxiliary power supply module 50. The first acquisition module 40 can collect the transmission current between the DC / DC conversion module 30 and the input / output interface 101 in real time, and then the main control module 10 can output a corresponding control signal according to the magnitude of the transmission current. When the transmission current is less than the first current threshold, it indicates that the battery pack 200 is not currently charging or discharging, and the main control module 10 outputs a first control signal, so that the DC / DC auxiliary power supply module 50 stops outputting a power signal in response to the first control signal, so that the DC / DC conversion module 30 is in standby mode, which can effectively reduce the power consumption of the battery management device. When the transmission current is greater than the second current threshold, it indicates that the battery pack 200 is in a charging or discharging state, and the main control module 10 outputs a second control signal, so that the DC / DC auxiliary power supply module 50 responds to the second control signal to output a power supply signal, so that the DC / DC conversion module 30 is in a normal working mode during the charging and discharging process of the battery pack 200, and can respond to the third control signal issued by the main control module 10 to adjust the working state to ensure that the battery pack 200 can work normally and stably during the charging and discharging process. In summary, the embodiment of the present invention can reduce the power consumption of the battery management device when the battery pack 200 is not in use, so that the power of the battery pack 200 can be maintained for a longer time, improve the battery energy utilization rate, and thus extend the actual service life of the battery pack 200.

[0051] On the basis of the above embodiment, optionally, the battery pack 200 may include multiple batteries, and the series-parallel structure between the multiple batteries can be set according to actual needs. Among them, the battery management module 20 is also used to collect the voltage of each battery in the battery pack 200. The battery can specifically be a battery composed of wide voltage cells, so that the battery pack 200 has a wider operating voltage range and a lower undervoltage threshold. Exemplarily, the battery can include a sodium ion battery, a lithium battery or a zinc ion battery.

[0052] On the basis of the above embodiments, optionally, when the DC / DC conversion module 30 works in the standby mode, if the transmission current is greater than the second current threshold, the main control module 10 switches from outputting the first control signal to outputting the second control signal. In this way, the DC / DC conversion module 30 can be controlled to switch to the normal working mode in a very short time, and the voltage fluctuation during the switching transition period is very small to ensure the stability of the voltage. It is understandable that the main control module 10 can continuously output the first control signal when the DC / DC conversion module 30 works in the standby mode.

[0053] When the DC / DC conversion module 30 is working in the normal working mode, if the transmission current is less than the first current threshold value and lasts for a preset time, the main control module 10 switches from outputting the second control signal to outputting the first control signal. That is to say, when the DC / DC conversion module 30 is working in the normal working mode, if the transmission current is continuously detected to be less than the first current threshold value within the preset time, indicating that the battery pack 200 is not in use, the DC / DC conversion module 30 can be switched to a low-power standby mode. It is understandable that the main control module 10 can continuously output the second control signal when the DC / DC conversion module 30 is working in the normal working mode. By setting the control module 10 to control the DC / DC conversion 30 to switch modes when the transmission current is less than the first current threshold value and lasts for a preset time, it can avoid the DC / DC conversion module 30 from switching too frequently, and the voltage of the input and output interface when the two working modes are switched between each other basically does not fluctuate. At the same time, it can also prevent the main control module 10 from misjudging, thereby ensuring the reliability of the DC / DC conversion module 30.

[0054] Figure 2 A schematic diagram of another battery management device provided by an embodiment of the present invention, referring to Figure 2 On the basis of the above embodiment, optionally, the DC / DC conversion module 30 includes: a DC / DC conversion unit 301 and a DC / DC drive unit 302. The first connection end of the DC / DC conversion unit 301 is connected to the battery management module 20, the second connection end of the DC / DC conversion unit 301 is connected to the input-output interface 101, and the control end of the DC / DC conversion unit 301 is connected to the output end of the DC / DC drive unit 302; wherein the transmission current is the current between the second connection end of the DC / DC conversion unit 301 and the input-output interface 101; the input end of the DC / DC drive unit 302 is connected to the main control module 10, and the power input end of the DC / DC drive unit 302 is connected to the DC / DC auxiliary power supply module 50; the DC / DC The drive unit 302 is used to sleep when the power input end does not receive a power signal input, so that the DC / DC conversion module 30 works in the standby mode; and the DC / DC drive unit 302 is used to be awakened when the power input end receives a power signal input, so that the DC / DC conversion module 30 works in the normal working mode; the DC / DC drive unit 302 is used to respond to the third control signal provided by the main control module 10 when awakened, and control the transmission of the corresponding drive signal to the control end of the DC / DC conversion unit 301, so as to drive the DC / DC conversion unit 301 to perform the action corresponding to the third control signal.

[0055] In this embodiment, the DC / DC conversion unit 301 serves as a voltage conversion component, connected to the electrical path between the battery pack 200 and the input / output interface 101, and is used for voltage conversion; the DC / DC drive unit 302 serves as a drive component, and is used to respond to the control of the main control module 10 and the DC / DC auxiliary power supply module 50 to drive the DC / DC conversion unit 301.

[0056] Continue to refer Figure 2 Optionally, the second connection end of the DC / DC conversion unit 301 is connected to the input-output interface 101 through a copper bar to achieve high-power current carrying.

[0057] On this basis, current sampling can also be implemented based on the copper strip. Specifically, the first acquisition module 40 is connected to the two ends of the copper strip respectively; the first acquisition module 40 is used to collect the voltage at the two ends of the copper strip, and determine the transmission current according to the voltage at the two ends of the copper strip. In this way, by reusing the copper strip as a sampling resistor, it is not necessary to set a separate sampling resistor in the battery management device, thereby saving production costs.

[0058] Continue to refer Figure 2 Optionally, the battery management module 20 includes: a switch unit 21 and a control unit 22. The switch unit 21 is connected between the first connection end of the DC / DC conversion unit 301 and the battery pack 200, and the control end of the switch unit 21 is connected to the main control module 10. The control unit 22 is connected to the battery pack 200 and the main control module 10 respectively; the control unit 22 is used to supply power to the DC / DC auxiliary power module 50, and the control unit 22 is also used to collect the total voltage of the battery pack 200 and transmit it to the main control module 10; the main control module 10 is also used to generate a third control signal according to the total voltage, and control the on-off state of the switch unit 21 according to the total voltage.

[0059] Specifically, the switch unit 21 is used to control the on / off of the electrical path between the battery pack 200 and the DC / DC conversion module 30. In this embodiment, the switch unit 21 is exemplarily controlled by the main control module 10, but this is not intended to limit the present invention. In other embodiments, the control end of the switch unit 21 may be connected to the control unit 22, and the control unit 22 controls the on / off of the switch unit 21.

[0060] Exemplarily, when the total voltage of the battery pack 200 is less than or equal to the first undervoltage protection threshold of the battery pack 200 / greater than the first overvoltage protection threshold of the battery pack 200, the main control module 10 controls the third control signal according to the total voltage to stop the DC / DC conversion module 30 from working, and controls the switch unit 21 to be in an open state according to the total voltage to avoid overcharging / overdischarging of the battery pack 200. When the battery pack 200 is in a normal charging and discharging state, the main control module 10 generates a third control signal according to the total voltage to control the DC / DC conversion module 30 to perform voltage conversion, and controls the switch unit 21 to be in a closed state according to the total voltage. Through this setting, the life of the battery pack 200 can be extended and the safety of the battery pack 200 can be ensured.

[0061] Continue to refer Figure 2 Optionally, the switch unit 21 includes a charging switch 211 and a discharging switch 212 connected in series between the first connection end of the DC / DC conversion unit 301 and the battery pack 200; the control end of the charging switch 211 and the control end of the discharging switch 212 are both connected to the main control module 10.

[0062] The following describes in detail the working process of the battery management device with respect to the possible structures of each module in the battery management device, but does not limit the present invention.

[0063] 1) When the input-output interface 101 is connected to a load, the main control module 10 controls the charging switch 211 and the discharging switch 212 to close to conduct the discharge path between the battery pack 200 and the load. In this case, when the total voltage of the battery pack 200 is less than or equal to the first undervoltage protection threshold of the battery pack 200, and / or when the voltage of at least one battery in the battery pack 200 is less than the second undervoltage protection threshold of the battery, the main control module 10 controls the third control signal to make the DC / DC drive unit 302 control the DC / DC conversion unit 301 to stop working, and the main control module 10 controls the discharge switch 212 to disconnect. That is, when the battery pack 200 is in an undervoltage state, the main control module 10 controls the DC / DC conversion unit 301 to turn off, and controls the discharge switch 212 to disconnect to cut off the discharge path of the battery pack 200, so that the input-output interface 101 is disabled. Both stopping working and not working are states where the DC / DC conversion module 30 is not working. Stopping working can be understood as the DC / DC conversion module 30 being converted to a non-working state due to receiving a related control signal during the working process.

[0064] 2) When the input-output interface 101 is connected to the charger, the main control module 10 controls the charging switch 211 to close to conduct the charging path from the charger to the battery pack. In this case, when the total voltage of the battery pack 200 is greater than the recovery threshold of the battery management module 20, the main control module 10 controls the discharge switch 212 to close and controls the DC / DC conversion unit 301 not to work. Among them, the recovery threshold is greater than the first undervoltage protection threshold. When the total voltage of the battery pack 200 is greater than or equal to the first overvoltage protection threshold of the battery pack 200, and / or when the voltage of at least one battery in the battery pack 200 is greater than the second overvoltage protection threshold of the battery, the main control module 10 controls the charging switch 211 to open to cut off the charging path of the battery pack 200, and controls the DC / DC conversion unit 301 to stop working. Through this setting, the safety and reliability of the battery pack 200 can be guaranteed.

[0065] Among them, when the input-output interface 101 is connected to the charger, and the total voltage of the battery pack 200 is greater than or equal to the recovery working voltage threshold of the DC / DC conversion unit 301, or when the input-output interface 101 is connected to the load and the transmission current is greater than the second current threshold, it is equivalent to providing the working conditions for the normal operation of the DC / DC conversion module 30. In the above case, the main control module 10 can generate a third control signal according to the total voltage of the battery pack 200 and the voltage of the input-output interface 101 to control the specific working state of the DC / DC conversion module 30 in the normal working mode. Among them, the recovery working voltage threshold can be specifically understood as the minimum voltage value that allows the DC / DC conversion unit 301 to work normally, which is greater than the first undervoltage protection threshold.

[0066] Specifically, when the input / output interface 101 is connected to the charger, the main control module 10 first controls the charging switch 211 to close. When the total voltage of the battery pack 200 is greater than the recovery threshold of the battery management module 20, the main control module 10 controls the discharge switch 212 to close so that the charging path between the charger and the battery pack 200 is turned on. The DC / DC auxiliary power supply module 50 puts the DC / DC conversion unit 301 in a normal working mode according to the second control signal output by the main control module 10. When the total voltage of the battery pack 200 is greater than or equal to the recovery working voltage threshold of the DC / DC conversion unit 301, the DC / DC conversion unit 301 is in a working state and stabilizes the voltage output by the charger. Exemplarily, when the battery pack 200 is charged, if the voltage of the charger is low, for example, lower than the total voltage of the battery pack 200, the DC / DC conversion unit 301 boosts the voltage of the charger to ensure stable charging of the battery pack 200. If the voltage of the charger is higher, for example, higher than the total voltage of the battery pack 200 , the DC / DC conversion unit 301 steps down the voltage of the charger or the DC / DC conversion unit 301 is in a through state to ensure stable charging of the battery pack 200 .

[0067] When the input / output interface 101 is connected to a load, if the total voltage of the battery pack 200 is less than the voltage required by the load, the DC / DC conversion unit 301 boosts the voltage of the battery pack 200 to ensure stable power supply to the load. If the total voltage of the battery pack 200 is greater than the voltage required by the load, the DC / DC conversion unit 301 steps down the voltage of the battery pack 200 or the DC / DC conversion unit 301 is in a through state to ensure stable power supply to the load.

[0068] The DC / DC conversion unit 301 being in the through state means that the DC / DC conversion unit 301 does not perform voltage conversion, so that the battery pack 200 is connected to the input-output interface 101 .

[0069] The technical solution of the embodiment of the present invention is to perform voltage conversion through the DC / DC conversion module 30 when the total voltage of the battery pack 200 is less than the load voltage, so as to ensure that the batteries in the battery pack 200 can supply power to the load within a wide voltage range, thereby improving the battery energy utilization rate. And when the voltage of the charger is lower than the total voltage of the battery pack 200, the voltage conversion is performed through the DC / DC conversion module 30, which can reduce the energy loss caused by voltage mismatch, thereby improving the charging efficiency. At the same time, the DC / DC conversion module 30 can dynamically adjust the output voltage according to the charging state of the battery pack 200 (such as voltage and current requirements), ensuring that the battery pack 200 always works under the best charging conditions to avoid overcharging or undercharging.

[0070] Continue to refer Figure 2 Optionally, the battery management module 20 also includes: a current limiting starting unit 23, which is connected in parallel to both ends of the discharge switch 212; the current limiting starting unit 23 is used to limit the current impact of the battery pack 200 at the initial charging stage to prevent excessive current from damaging the battery pack 200 or the circuit, thereby ensuring the safe startup of the battery management module 20.

[0071] Specifically, the current limiting start unit 23 may include: a current limiting resistor R and a switch tube 231 connected in series, wherein the control electrode of the switch tube 231 is connected to the control unit 22 (or may also be connected to the main control module 10). The current limiting resistor R and the switch tube 231 are connected in series and then connected in parallel to both ends of the discharge switch 212.

[0072] Continue to refer Figure 2Optionally, the battery management device further includes a second acquisition module 60, which is connected to the input / output interface 101 and the main control module 10 respectively. The second acquisition module 60 is used to collect the voltage of the input / output interface 101 and transmit it to the main control module 10; the main control module 10 is also used to generate a third control signal according to the voltage of the input / output interface 101, specifically, to generate a specific third control signal according to the voltage of the input / output interface 101 and the total voltage of the battery pack 200, so as to control the working state of the DC / DC conversion module 30.

[0073] For example, when the input / output interface 101 is connected to a load, the second acquisition module 60 can acquire the interface voltage transformation when the battery pack 200 supplies power to the load, and feed the transformation back to the main control module 10, so that the main control module 10 performs corresponding control to ensure stable power supply to the load. That is to say, in the battery management device provided in this embodiment, the main control module 10 can adjust the internal state of the device according to the voltage signal acquired by the second acquisition module 60, so as to achieve an ideal voltage stabilization value.

[0074] It should be noted that, when the battery pack 200 is under voltage, the DC / DC auxiliary power module 50 can supply power to the DC / DC conversion module 30 and the main control module 10 to ensure the normal operation of the DC / DC conversion module 30 and the main control module 10 when the battery pack 200 is under voltage. This setting can effectively solve the problem of not being able to wake up normally when the battery pack 200 is under voltage due to the narrow standby voltage width, thereby improving the reliability of the DC / DC conversion module 30 and the main control module 10.

[0075] On the basis of the above embodiments, optionally, the first acquisition module 40 is also used to acquire the voltage and / or temperature of the input / output interface 101; the second acquisition module 60 is also used to acquire the temperature and / or transmission current of the input / output interface 101; the main control module 10 is also used to control the third control signal according to at least one of the transmission current, the voltage of the input / output interface 101 and the temperature of the input / output interface 101, so as to control the working state of the DC / DC conversion module 30. Exemplarily, when the transmission current is greater than the set current threshold, the main control module 10 controls the DC / DC conversion module 30 to stop working to prevent overcurrent damage to components in the circuit. When the voltage of the input / output interface 101 is less than the set voltage threshold, the main control module 10 controls the DC / DC conversion module 30 to perform voltage conversion to ensure the stability of the input voltage / output voltage. When the temperature of the input / output interface 101 is greater than the set temperature threshold, the main control module 10 controls the DC / DC conversion module 30 to stop working to prevent thermal damage to components in the circuit.

[0076] On the basis of the above embodiments, optionally, the first acquisition module 40 and / or the second acquisition module 60 are also used to acquire the temperature of the input-output interface 101; the main control module 10 is also used to control the transmission current to be within a first current range when the temperature of the input-output interface 101 is within a set temperature range; and, when the temperature of the input-output interface 101 is outside the set temperature range, control the transmission current to be within a second current range; wherein the current upper limit value of the first current range is greater than the current upper limit value of the second current range, and the current upper limit value of the first current range and the current upper limit value of the second current range are both greater than the second current threshold.

[0077] Among them, the set temperature range refers to the temperature range in which the battery pack 200 can be charged and discharged normally. For example, the set temperature range can be 1°C-50°C. Exemplarily, when the input-output interface 101 is connected to the charger, when the temperature of the input-output interface 101 is within the set temperature range, the main control module 10 can control the DC / DC conversion module 30 to gradually increase the current. When the current gradually increases to the upper limit of the current in the first current range, the DC / DC conversion module 30 is controlled to operate stably to enable the charger to fast charge the battery pack 200. When the temperature of the input-output interface 101 is outside the set temperature range, the main control module 10 can control the DC / DC conversion module 30 to limit the charging and discharging current, thereby protecting the safety of the battery pack 200.

[0078] On the basis of the above embodiments, optionally, the battery management device also includes: a state control module 70; the state control module 70 is connected to the main control module 10, and the state control module 70 is used to output a state control instruction; when the input-output interface 101 is connected to a load, the main control module 10 is used to adjust the third control signal in response to the state control instruction, so that the DC / DC conversion module 30 operates in a working state corresponding to the state control instruction; wherein the DC / DC conversion module 30 provides different voltages and / or currents to the load in different working states.

[0079] The state control module 70 may be, for example, a dial switch, a button or a knob, for the user to manually output the state control instruction. Alternatively, the state control module 70 may be, for example, a touch screen, a remote controller or a network interface, for the user to output the state control instruction.

[0080] Exemplarily, when the total voltage of the battery pack 200 is 30V, if the voltage required by the load is 60V, the corresponding state control instruction is output by controlling the state control module 70 and transmitted to the main control module 10. The state control instruction is used to indicate the required output voltage and / or current. The main control module 10 outputs a third control signal in response to the state control instruction, and then the DC / DC conversion module 30 adjusts the output voltage and / or current to meet the current charging requirements of the load. Through this setting, the battery pack 200 can provide different currents and / or voltages to the load, thereby enriching its application scenarios. It can be understood that in other embodiments, the output of the battery pack 200 can also be 48V or 72V.

[0081] An embodiment of the present invention further provides a battery system, including a battery pack and the battery management device provided by any embodiment of the present invention, and therefore has corresponding beneficial effects.

[0082] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0083] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A battery management device, characterized in that: include: Main control module; A battery management module, connected to the battery pack and the main control module respectively; A DC / DC conversion module, connected to the battery management module, the input and output interfaces of the battery management device and the main control module respectively; the input and output interfaces are used to connect to a load or a charger; A first acquisition module, connected to the main control module, for acquiring the transmission current between the DC / DC conversion module and the input / output interface, and providing the current to the main control module; A DC / DC auxiliary power supply module is respectively connected to the battery management module, the main control module and the DC / DC conversion module; the battery management module is used to supply power to the DC / DC auxiliary power supply module; the main control module is used to transmit a first control signal to the DC / DC auxiliary power supply module when the transmission current is less than a first current threshold, and the DC / DC auxiliary power supply module is used to stop outputting a power signal in response to the first control signal, so that the DC / DC conversion module works in a standby mode; and the main control module is used to transmit a second control signal to the DC / DC auxiliary power supply module when the transmission current is greater than a second current threshold, and the DC / DC auxiliary power supply module is used to output the power signal in response to the second control signal, so that the DC / DC conversion module works in a normal working mode, and the DC / DC conversion module is used to respond to a third control signal provided by the main control module in the normal working mode and perform corresponding actions; wherein, the second current threshold is greater than or equal to the first current threshold.

2. The battery management device according to claim 1, characterized in that: When the DC / DC conversion module operates in the standby mode, if the transmission current is greater than the second current threshold, the main control module switches from outputting the first control signal to outputting the second control signal; When the DC / DC conversion module operates in the normal working mode, if the transmission current is less than the first current threshold and lasts for a preset time, the main control module switches from outputting the second control signal to outputting the first control signal.

3. The battery management device according to claim 1, characterized in that: The DC / DC conversion module includes: a DC / DC conversion unit and a DC / DC driving unit; The first connection end of the DC / DC conversion unit is connected to the battery management module, the second connection end of the DC / DC conversion unit is connected to the input-output interface, and the control end of the DC / DC conversion unit is connected to the output end of the DC / DC drive unit; wherein the transmission current is the current between the second connection end and the input-output interface; The input end of the DC / DC drive unit is connected to the main control module, and the power input end of the DC / DC drive unit is connected to the DC / DC auxiliary power module; the DC / DC drive unit is used to sleep when the power input end does not receive the power signal input, so that the DC / DC conversion module works in the standby mode; and the DC / DC drive unit is used to be awakened when the power input end receives the power signal input, so that the DC / DC conversion module works in the normal working mode; the DC / DC drive unit is used to respond to the third control signal provided by the main control module when awakened, and control the drive signal transmitted to the control end of the DC / DC conversion unit.

4. The battery management device according to claim 3, characterized in that: The second connection end of the DC / DC conversion unit is connected to the input-output interface via a copper bar; The first acquisition module is connected to both ends of the copper bar respectively; the first acquisition module is used to collect the voltage at both ends of the copper bar, and determine the transmission current according to the voltage at both ends of the copper bar.

5. The battery management device according to claim 3, characterized in that: The battery management module comprises: A switch unit is connected between the first connection end of the DC / DC conversion unit and the battery pack, and a control end of the switch unit is connected to the main control module; A control unit is respectively connected to the battery pack and the main control module; wherein the control unit is used to supply power to the DC / DC auxiliary power supply module, and the control unit is also used to collect the total voltage of the battery pack and transmit it to the main control module; the main control module is also used to generate the third control signal according to the total voltage, and control the on-off state of the switch unit according to the total voltage.

6. The battery management device according to claim 5, characterized in that: The switch unit comprises a charging switch and a discharging switch connected in series between the first connecting end and the battery pack; the control end of the charging switch and the control end of the discharging switch are both connected to the main control module; When the input / output interface is connected to the load, the main control module controls the charging switch and the discharging switch to be closed; when the total voltage of the battery pack is less than or equal to the first undervoltage protection threshold of the battery pack, and / or when the voltage of at least one battery in the battery pack is less than the second undervoltage protection threshold of the battery, the main control module controls the third control signal to make the DC / DC drive unit control the DC / DC conversion unit to stop working, and the main control module controls the discharging switch to be disconnected; When the input / output interface is connected to the charger, the main control module controls the charging switch to be closed; when the total voltage of the battery pack is greater than the recovery threshold of the battery management module, the main control module controls the discharging switch to be closed, and controls the DC / DC conversion unit not to work; when the total voltage of the battery pack is greater than or equal to the first overvoltage protection threshold of the battery pack, and / or when the voltage of at least one battery in the battery pack is greater than the second overvoltage protection threshold of the battery, the main control module controls the charging switch to be disconnected, and controls the DC / DC conversion unit to stop working; Among them, when the input-output interface is connected to the charger and the total voltage of the battery pack is greater than or equal to the recovery working voltage threshold of the DC / DC conversion unit, or when the input-output interface is connected to the load and the transmission current is greater than the second current threshold, the main control module generates the third control signal according to the total voltage of the battery pack and the voltage of the input-output interface.

7. The battery management device according to claim 6, characterized in that: The battery management module further includes: a current limiting start unit connected in parallel to both ends of the discharge switch; the current limiting start unit includes: a current limiting resistor and a switch tube connected in series, and the control electrode of the switch tube is connected to the control unit.

8. The battery management device according to claim 1, characterized in that: Also includes: A second acquisition module, connected to the input and output interface and the main control module, respectively, for acquiring the voltage of the input and output interface and transmitting it to the main control module; The main control module is further used to generate the third control signal according to the voltage of the input / output interface.

9. The battery management device according to claim 8, characterized in that: The first acquisition module is further used to acquire the voltage and / or temperature of the input / output interface; the second acquisition module is further used to acquire the temperature of the input / output interface and / or the transmission current; The main control module is further used to control the third control signal according to at least one of the transmission current, the voltage of the input / output interface, and the temperature of the input / output interface.

10. The battery management device according to claim 8, characterized in that: The first acquisition module and / or the second acquisition module is further used to acquire the temperature of the input and output interface; The main control module is also used to control the transmission current to be within a first current range when the temperature of the input / output interface is within a set temperature range; and to control the transmission current to be within a second current range when the temperature of the input / output interface is outside the set temperature range; wherein the current upper limit value of the first current range is greater than the current upper limit value of the second current range, and both the current upper limit value of the first current range and the current upper limit value of the second current range are greater than the second current threshold.

11. The battery management device according to claim 1, characterized in that: Also includes: State control module; the state control module is connected to the main control module, and the state control module is used to output state control instructions; When the input-output interface is connected to the load, the main control module is used to adjust the third control signal in response to the state control instruction, so that the DC / DC conversion module operates in a working state corresponding to the state control instruction; wherein the DC / DC conversion module provides different voltages and / or currents to the load in different working states.

12. The battery management device according to claim 1, characterized in that: The batteries in the battery pack include sodium ion batteries, lithium batteries or zinc ion batteries.

13. A battery system, characterized in that: include: A battery pack and a battery management device as claimed in any one of claims 1 to 12.

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