Storage battery online monitoring management device and working method thereof

Abstract

The invention discloses a storage battery online monitoring and management device and a working method thereof. The device comprises a concentrator, a single internal resistance module, a total voltage module and a current module, wherein the current module is connected with the total voltage module; the total voltage module is connected with the monomer internal resistance module; the current module is connected with the concentrator; each single internal resistance module comprises a controller, a module bus interface, a communication and automatic addressing isolation circuit and an acquisition circuit; the communication and automatic addressing isolation circuit and the acquisition circuit are respectively connected with the module bus interface; the acquisition circuit is used for acquiring battery voltage, negative pole temperature, internal resistance measurement discharge current and internal resistance measurement discharge battery voltage difference; the module bus interface is connected with the total voltage module; and the controller is respectively connected with the communication and automatic addressing isolation circuit and the acquisition circuit. By implementing the device provided by the invention, the online monitoring of the storage battery can be effectively and accurately realized, and the reliability and the safety of the direct-current standby power of the storage battery in various scenes are ensured.

Description

Technical Field

[0001] This invention relates to the field of battery monitoring technology, and in particular to an online monitoring and management device for storage batteries and its working method. Background Technology

[0002] Online battery monitoring technology plays a crucial role in the monitoring and management of DC backup power battery packs in industries such as power plants, substations, communication base stations, data centers, and rail transportation. If a battery pack fails to reliably provide DC backup power, it will cause significant economic losses to these industries. Internal resistance is one of the key indicators for assessing battery health, and its measurement methods are mainly divided into two types: DC discharge method and AC injection method. Although the AC injection method offers higher accuracy, its complex circuitry, susceptibility to interference, and high cost limit its widespread practical application. Therefore, the industry typically uses the DC discharge method to measure battery internal resistance.

[0003] However, when using the DC discharge method to measure internal resistance, a large discharge current is often required to ensure accuracy. This not only leads to a loss of battery capacity but also causes aging and deformation of the electrode materials, thus shortening the battery's lifespan. More seriously, if the internal resistance measurement discharge circuit becomes uncontrolled, it may not only fail to complete the internal resistance measurement but also cause the battery to continue discharging, further reducing battery capacity and even causing safety accidents.

[0004] Therefore, it is necessary to design a new device to achieve effective and accurate online monitoring of batteries, and to ensure the reliability and safety of DC backup power for batteries in various scenarios. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide an online monitoring and management device for batteries and its working method.

[0006] To solve the above-mentioned technical problems, the objective of this invention is achieved through the following technical solution: A battery online monitoring and management device is provided, comprising: a concentrator, a single-cell internal resistance module, a total voltage module, and a current module; wherein, the current module is connected to the total voltage module; the total voltage module is connected to the single-cell internal resistance module; the current module is connected to the concentrator; the single-cell internal resistance module includes a controller, a module bus interface, a communication and automatic addressing isolation circuit, and a data acquisition circuit; the communication and automatic addressing isolation circuit and the data acquisition circuit are respectively connected to the module bus interface; the data acquisition circuit is used to acquire battery voltage, negative terminal temperature, internal resistance measurement discharge current, and internal resistance measurement discharge battery voltage difference; the module bus interface is connected to the total voltage module; the controller is connected to both the communication and automatic addressing isolation circuit and the data acquisition circuit.

[0007] The further technical solution is as follows: the module bus interface includes dual RJ45 ports.

[0008] The further technical solution is as follows: the single-unit internal resistance module also includes a power isolation circuit; the power isolation circuit is connected to the module bus interface.

[0009] The further technical solution is as follows: the power isolation circuit includes a TVS diode, a reverse protection diode D1, a step-down power supply U1, an isolation power chip U6, a linear regulator U7, and a reference power supply U4; the TVS diode is connected to the reverse protection diode D1; the reverse protection diode D1 is connected to the step-down power supply U1; the isolation power chip U6 is connected to the isolation transformer; the isolation transformer is connected to the linear regulator U7; and the linear regulator U7 is connected to the current module.

[0010] The further technical solution is as follows: the communication and automatic addressing isolation circuit includes optocoupler U2, optocoupler U3, optocoupler U5, dual-channel digital isolator U9, and transceiver U8; the module bus interface is connected to the optocoupler U2; the controller is connected to the optocoupler U3; the optocoupler U3 is connected to the module bus interface; the controller is connected to the transceiver U8 through the optocoupler U5; the controller is connected to the dual-channel digital isolator U9; the dual-channel digital isolator U9 is connected to the transceiver U8; the transceiver U8 is connected to a common-mode inductor L2.

[0011] The further technical solution is as follows: the acquisition circuit includes a battery voltage acquisition circuit, a negative electrode temperature acquisition circuit, an internal resistance measurement discharge current acquisition circuit, and an internal resistance measurement discharge battery differential pressure acquisition circuit; the battery voltage acquisition circuit, the negative electrode temperature acquisition circuit, the internal resistance measurement discharge current acquisition circuit, and the internal resistance measurement discharge battery differential pressure acquisition circuit are respectively connected to the controller.

[0012] The further technical solution is as follows: the battery voltage acquisition circuit includes a voltage divider resistor R18, a voltage divider resistor R20, a filter capacitor C28, an analog switch U10, a voltage follower U11, and a filter network; the voltage divider resistors R18 and R20 are respectively connected to the battery; the voltage divider resistor R18 is connected to the analog switch U10 through the filter capacitor C28; the analog switch U10 is connected to the controller; the analog switch U10 is connected to the voltage follower U11; the voltage follower U11 is connected to the filter network; and the filter network is connected to the controller.

[0013] The further technical solution is as follows: the negative electrode temperature acquisition circuit includes an NTC resistor, a voltage divider resistor R23, a filter capacitor C32, an analog switch U10, a voltage follower U11, and a filter network; the NTC resistor and the voltage divider resistor R23 are respectively connected to the battery; the NTC resistor is connected to the filter capacitor C32; the NTC resistor is connected to the analog switch U10; the analog switch U10 is connected to the controller; the analog switch U10 is connected to the voltage follower U11; the voltage follower U11 is connected to the filter network; and the filter network is connected to the controller.

[0014] The further technical solution is as follows: the internal resistance measurement discharge current acquisition circuit includes a resistor R35 and a filter network; the resistor R35 is connected to the battery; the resistor R35 is connected to the filter network; the filter network is connected to the controller; the single-unit internal resistance module includes a magnetic latching relay, and the magnetic latching relay is connected to the internal resistance measurement discharge current acquisition circuit.

[0015] In addition, to overcome the shortcomings of the prior art, the present invention also provides a method for operating the above-mentioned online monitoring and management device for batteries, comprising:

[0016] The concentrator provides 24V power and uses the acquisition bus to transmit addressing signals and RS485 communication signals.

[0017] The concentrator collects voltage, internal resistance, and temperature information of each battery cell through the individual cell internal resistance module, monitors the overall voltage and current of the battery pack through the total voltage module and current module, and communicates with the user host or monitoring platform through Modbus-RTU or Modbus-TCP protocol to read data and issue commands.

[0018] The advantages of this invention compared to existing technologies are as follows: This invention achieves effective and accurate monitoring of battery status through the coordinated operation of a concentrator, individual cell internal resistance module, total voltage module, and current module. Specifically, the individual cell internal resistance module integrates a controller, module bus interface, communication and automatic addressing isolation circuit, and acquisition circuit. It can acquire key parameters such as battery voltage, negative terminal temperature, internal resistance measurement, discharge current, and voltage difference. Through connection with the total voltage module and current module, it ensures accurate data transmission to the concentrator for comprehensive analysis. The automatic addressing function simplifies the system configuration process, while the isolation circuit ensures the stability and security of data transmission. This design not only improves the accuracy of battery performance monitoring but also enhances the reliability and security of DC backup power systems in various application scenarios, thereby effectively preventing potential faults and ensuring the continuous and stable operation of the system.

[0019] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 A schematic block diagram of an online monitoring and management device for a storage battery provided in an embodiment of the present invention;

[0022] Figure 2 A specific circuit diagram of the module bus interface provided in the embodiments of the present invention;

[0023] Figure 3 A specific circuit diagram of the power isolation circuit provided in the embodiments of the present invention;

[0024] Figure 4 A specific circuit diagram of the communication and automatic addressing isolation circuit provided in the embodiments of the present invention;

[0025] Figure 5 A detailed circuit diagram of the acquisition circuit provided in the embodiments of the present invention;

[0026] Explanation of the markings in the image:

[0027] 10. Concentrator; 20. Individual internal resistance module; 30. Total voltage module; 40. Current module. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0030] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0031] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0032] Online battery monitoring technology is crucial for monitoring DC backup power battery packs in industries such as power plants, substations, communication base stations, data centers, and rail transportation. Internal resistance, a key indicator for assessing battery health, is primarily measured using the more practical DC discharge method rather than the costly and interference-prone AC injection method. However, while the DC discharge method ensures measurement accuracy, it requires a large discharge current. This not only causes battery capacity loss and electrode material aging and deformation, shortening battery life, but also, if not properly controlled, can lead to continuous discharge, further damaging the battery and even causing safety accidents. Therefore, achieving a reasonable balance between the accuracy of internal resistance measurement and battery safety protection is a significant challenge facing the industry.

[0033] Therefore, embodiments of the present invention provide an online monitoring and management device for batteries, which enables effective and accurate online monitoring of batteries, ensuring the reliability and safety of DC backup power for batteries in various scenarios.

[0034] This online battery monitoring and management device, through the coordinated operation of a concentrator 10, a single-cell internal resistance module 20, a total voltage module 30, and a current module 40, achieves precise acquisition and monitoring of key parameters of the battery pack, such as voltage, internal resistance, and temperature. The single-cell internal resistance module 20 integrates a controller, communication and automatic addressing isolation circuits, and acquisition circuits. It can effectively measure battery voltage, negative terminal temperature, internal resistance, discharge current, and differential voltage, and efficiently exchange data with other modules through a dual RJ45 port module bus interface. The power isolation circuit ensures electrical safety between components, while the communication and automatic addressing isolation circuit ensures the stability and reliability of signal transmission. The entire system communicates with an external monitoring platform using Modbus-RTU or Modbus-TCP protocols, providing real-time feedback of battery status information. This ensures the reliability and safety of DC backup power in various application scenarios, such as power plants and substations, while extending battery life and preventing potential safety accidents.

[0035] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0036] Please see Figure 1 A battery online monitoring and management device includes: a concentrator 10, a single-cell internal resistance module 20, a total voltage module 30, and a current module 40; wherein, the current module 40 is connected to the total voltage module 30; the total voltage module 30 is connected to the single-cell internal resistance module 20; the current module 40 is connected to the concentrator 10; the single-cell internal resistance module 20 includes a controller, a module bus interface, a communication and automatic addressing isolation circuit, and a data acquisition circuit; the communication and automatic addressing isolation circuit and the data acquisition circuit are respectively connected to the module bus interface; the data acquisition circuit is used to acquire battery voltage, negative terminal temperature, internal resistance measurement discharge current, and internal resistance measurement discharge battery voltage difference; the module bus interface is connected to the total voltage module 30; the controller is respectively connected to the communication and automatic addressing isolation circuit and the data acquisition circuit.

[0037] The device in this embodiment aims to solve the problems of large discharge current and lack of discharge circuit protection during internal resistance measurement in the prior art. This device can accurately collect and monitor various key parameters of the battery, such as individual cell voltage, internal resistance, temperature, and the overall voltage and current of the battery pack, thereby ensuring the reliability and safety of DC backup power in various application scenarios.

[0038] Specifically, the concentrator 10 provides 6 acquisition bus interfaces, and the modules are cascaded in a "daisy-chain" manner through an 8-core twisted pair acquisition bus, namely the individual internal resistance module 20, the total voltage module 30, and the current module 40.

[0039] It supports automatic addressing, enabling each module to be accurately identified and matched with a specific battery pack; it uses Modbus-RTU or Modbus-TCP protocols to communicate with external monitoring platforms for data reading and command issuance.

[0040] The single-unit internal resistance module 20 includes a controller, a module bus interface, communication and automatic addressing isolation circuits, and a data acquisition circuit. The data acquisition circuit is used to acquire battery voltage, negative terminal temperature, internal resistance measurement discharge current, and discharge battery voltage difference; it is designed with dedicated power isolation circuits and communication isolation circuits to ensure signal transmission stability and electrical safety; it has a built-in magnetic latching relay as a safety guarantee for the discharge circuit, which can physically disconnect the circuit in the event of a fault to prevent accidents.

[0041] The single-unit internal resistance module includes a magnetic latching relay, which is connected to the internal resistance measurement discharge current acquisition circuit.

[0042] The total voltage module 30 is responsible for monitoring the overall voltage status of the entire battery pack.

[0043] The current module 40 focuses on the current changes of the battery pack and supports up to two current acquisition modules per pack.

[0044] To improve the accuracy of internal resistance measurement, the device in this embodiment adopts a 4-wire measurement method, which is used to apply current and measure voltage respectively, reducing the influence of test line resistance and contact resistance on the measurement results. In order to reduce the loss of battery capacity during internal resistance measurement, a low-current discharge scheme of less than 1.5A is designed, which also extends battery life. It can monitor the status of the discharge circuit in real time and take immediate measures when an abnormality is detected (such as MOS switch failure), including disconnecting the magnetic latching relay and sending a fault notification to the monitoring platform.

[0045] The device in this embodiment achieves comprehensive and efficient monitoring of battery status through a precisely designed hardware architecture and intelligent software algorithms. It not only improves monitoring accuracy but also significantly enhances system safety and reliability, making it suitable for DC backup power needs in various scenarios such as power plants and substations. Furthermore, the device possesses excellent scalability and compatibility, allowing for flexible configuration adjustments to meet the requirements of battery management systems of different scales.

[0046] Each battery in the battery pack needs to be equipped with a single cell internal resistance module 20, and each battery pack can be configured with a maximum of 2 current acquisition modules and 1 total voltage acquisition module.

[0047] In one embodiment, please refer to Figure 2 The aforementioned module bus interface includes dual RJ45 ports.

[0048] The bus interface is designed to support power supply, RS485 communication, and automatic addressing. It uses dual RJ45 ports, labeled COM_IN and COM_OUT respectively.

[0049] Power supply: The module is supplied with the required operating power via the 24V / GND pin.

[0050] RS485 communication: Data is sent and received using two pins, RS485_A and RS485_B, to ensure a stable and reliable communication connection between modules.

[0051] In the COM_IN port, Addr_IN serves as the automatic addressing input signal. It is responsible for receiving the addressing output signal from the previous module, which is a key part of implementing automatic addressing in "daisy-chain" cascading mode.

[0052] Correspondingly, in the COM_OUT port, Addr_OUT serves as an automatic addressing output signal, passing the address information of the current module to the next module, and so on, forming a complete address chain.

[0053] This design allows each module to be uniquely identified within the network and simplifies the installation process, eliminating the need to manually set the address of each module. Specifically, when multiple modules are connected in a daisy-chain manner, the first module obtains its initial address signal (Addr_IN) from concentrator 10, then generates its own address and passes it to the next module via Addr_OUT, and so on, until all modules are correctly numbered. This not only improves the system's ease of use but also enhances its flexibility and scalability.

[0054] In one embodiment, the aforementioned single-unit internal resistance module 20 further includes a power isolation circuit; the power isolation circuit is connected to the module bus interface.

[0055] In one embodiment, please refer to Figure 3 The aforementioned power isolation circuit includes a TVS diode, a reverse protection diode D1, a step-down power supply U1, an isolation power chip U6, a linear regulator U7, and a reference power supply U4; the TVS diode is connected to the reverse protection diode D1; the reverse protection diode D1 is connected to the step-down power supply U1; the isolation power chip U6 is connected to the isolation transformer; the isolation transformer is connected to the linear regulator U7; and the linear regulator U7 is connected to the current module 40.

[0056] In this embodiment, +24V input power supply refers to the +24V input power supply of the power isolation circuit.

[0057] TVS diodes are used to protect downstream circuits from voltage spikes. When an abnormally high input voltage occurs, the TVS diode quickly conducts, clamping the excessive voltage to a safe value, thus protecting the downstream circuits. The reverse-biased diode D1 prevents circuit damage caused by reverse power connection. If the power supply is reversed, D1 will block the current, protecting the circuit from damage.

[0058] To ensure circuit safety, a TVS diode is first used to prevent damage from instantaneous high voltage. Then, the current flows through a reverse connection protection diode D1 to prevent damage caused by incorrect power connection.

[0059] The step-down power supply circuit consists of components such as U1, L1, and D2, which reduce the +24V voltage to +5V. This collective action ensures a stable voltage drop, providing the +5V power required by subsequent circuits. The specific working process is as follows:

[0060] The step-down chip U1 controls the switching frequency and duty cycle to adjust the output voltage.

[0061] Inductor L1 stores energy when the switch is on and releases energy when the switch is off, thus smoothing the output voltage.

[0062] The freewheeling diode D2 provides a current path when the switch is off, preventing the inductor from generating a reverse electromotive force that could damage the circuit.

[0063] Filter capacitors C3, C7, and C8 filter out high-frequency noise, further smooth the output voltage, and ensure the stability of +5V.

[0064] +5V is the primary power supply for the isolation circuit, which includes the RS485 communication circuit and the automatic addressing circuit.

[0065] The RS485 communication circuit enables communication between modules through the RS485 interface.

[0066] Automatic addressing circuitry is used for automatic addressing between modules, ensuring that each module has a unique address.

[0067] The isolated DC / DC converter, consisting of components such as U6 / T1, converts +5V to +5V_ISO to power the secondary side of the isolation circuit. This design not only ensures the stability of the power supply but also improves the safety of the entire system.

[0068] The isolation power supply chip U6 is responsible for voltage conversion and electrical isolation;

[0069] Transformer T1 provides electrical isolation, ensuring that there is no direct electrical connection between the primary and secondary sides, thus improving safety.

[0070] The U7 linear regulator regulates +5V_ISO to +3.3V to power devices such as the MCU on the secondary side.

[0071] The reference power supply U4 provides a stable reference voltage VREF, which serves as the reference voltage for the MCU ADC, ensuring the accuracy of ADC measurements.

[0072] Specifically, +5V_ISO is further converted to +3.3V by a linear regulator U7 to power secondary devices such as the MCU. Simultaneously, another reference power supply U4 generates VREF, which serves as the reference voltage for the ADC (analog-to-digital converter) in the controller, ensuring the accuracy of signal conversion.

[0073] +5V_ISO also provides power to the magnetic latching relay, ensuring its proper functioning and physically disconnecting the discharge circuit in the event of a fault, thus protecting the battery.

[0074] +5V_ISO is also directly supplied to the magnetic latching relay. This is typically used in applications that require low power consumption to maintain the state, such as in battery management systems, where the circuit can be cut off when an abnormality is detected to protect the system.

[0075] In summary, this circuit system achieves the conversion from high voltage input to various low voltage outputs through a series of voltage transformation, isolation, and protection measures, and provides a reliable and stable power supply for different application scenarios.

[0076] In one embodiment, please refer to Figure 4 The aforementioned communication and automatic addressing isolation circuit includes optocoupler U2, optocoupler U3, optocoupler U5, dual-channel digital isolator U9, and transceiver U8; the module bus interface is connected to optocoupler U2; the controller is connected to optocoupler U3; optocoupler U3 is connected to the module bus interface; the controller is connected to transceiver U8 through optocoupler U5; the controller is connected to dual-channel digital isolator U9; dual-channel digital isolator U9 is connected to transceiver U8; and transceiver U8 is connected to a common-mode inductor L2.

[0077] Specifically, the automatic addressing input signal (Addr_IN) from the bus interface is first electrically isolated through optocoupler U2. This isolation design effectively prevents external interference from affecting the internal circuitry and ensures system safety.

[0078] After being isolated by U2, the Addr_IN signal is converted to the Addr_SET_IN signal and then connected to an I / O pin of the controller. The MCU reads this signal to identify the current module's position on the bus network.

[0079] Based on the received Addr_SET_IN signal and other logical operations, the controller will generate an Addr_SET_OUT signal.

[0080] The Addr_SET_OUT signal is isolated by another optocoupler U3, converted into an Addr_OUT signal, and finally transmitted back to the bus interface. This Addr_OUT signal will serve as the Addr_IN signal for the next module, enabling automatic addressing of modules throughout the bus network.

[0081] The controller is also responsible for generating an RS485 transmit / receive enable signal, which is isolated by optocoupler U5 and then connected to the enable pin of RS485 transceiver U8. In this way, the MCU can control the enable signal to determine when to enable or disable RS485 communication.

[0082] The controller's RX_485 and TX_485x signals represent received and transmitted data, respectively. These signals are isolated by a dual-channel digital isolator U9 to ensure data transmission stability and interference immunity.

[0083] The isolated RX_485 and TX_485x signals are connected to the data receiver and transmitter of RS485 transceiver U8, respectively. Transceiver U8 is responsible for converting TTL level signals into RS485 standard differential signals.

[0084] The A / B signals output by transceiver U8 are differential signals used for RS485 communication. After being processed by filtering and electromagnetic compatibility (EMC) circuits, these signals are further improved in terms of signal quality and anti-interference capability, and are finally output as RS485_A and RS485_B signals, which are connected to the bus interface to complete the physical transmission of data.

[0085] This circuit design achieves electrical isolation of signals through multiple optocouplers and digital isolators, ensuring stable operation of the system in complex electromagnetic environments. Meanwhile, the controller, as the core control unit, coordinates the processing of automatic addressing signals and the control of RS485 communication, enabling the entire bus network to operate efficiently and reliably.

[0086] In one embodiment, the aforementioned acquisition circuit includes a battery voltage acquisition circuit, a negative terminal temperature acquisition circuit, an internal resistance measurement discharge current acquisition circuit, and an internal resistance measurement discharge battery differential pressure acquisition circuit; the battery voltage acquisition circuit, the negative terminal temperature acquisition circuit, the internal resistance measurement discharge current acquisition circuit, and the internal resistance measurement discharge battery differential pressure acquisition circuit are respectively connected to the controller.

[0087] In one embodiment, please refer to Figure 5 The battery voltage acquisition circuit includes voltage divider resistors R18 and R20, filter capacitor C28, analog switch U10, voltage follower U11, and filter network. Voltage divider resistors R18 and R20 are connected to the battery. Voltage divider resistor R18 is connected to analog switch U10 through filter capacitor C28. Analog switch U10 is connected to the controller. Analog switch U10 is connected to voltage follower U11. Voltage follower U11 is connected to the filter network. The filter network is connected to the controller.

[0088] Specifically, the voltage across the battery terminals is acquired via BAT_U+ and BAT_U-. BAT_U+ is connected to the positive terminal of the battery, and BAT_U- is connected to the negative terminal. The battery voltage is divided by resistors R18 and R20, and then filtered by capacitor C28 to remove high-frequency noise and ensure signal stability. The processed battery voltage signal is then input to channel B1 of the two-to-one analog switch U10.

[0089] In one embodiment, please refer to Figure 5The negative electrode temperature acquisition circuit includes an NTC resistor, a voltage divider resistor R23, a filter capacitor C32, an analog switch U10, a voltage follower U11, and a filter network. The NTC resistor and the voltage divider resistor R23 are connected to the battery. The NTC resistor is connected to the filter capacitor C32. The NTC resistor is connected to the analog switch U10. The analog switch U10 is connected to the controller. The analog switch U10 is connected to the voltage follower U11. The voltage follower U11 is connected to the filter network. The filter network is connected to the controller.

[0090] The temperature of the negative terminal is measured using an NTC thermistor. The NTC resistor and R23 form a voltage divider circuit, the resistance of which changes with temperature, thus reflecting the temperature information. The voltage-divided signal is filtered by capacitor C32 to further improve the signal quality. The filtered temperature signal is then input to channel B0 of U10.

[0091] The channel selection of analog switch U10 is controlled by the controller, which selects either battery voltage or negative terminal temperature signal as needed. The selected signal is buffered by voltage follower U11 to maintain signal integrity. Finally, the signal is fed into the differential ADC0 channel of the controller after passing through the filtering network for analog-to-digital conversion.

[0092] In one embodiment, please refer to Figure 5 The internal resistance measurement and discharge current acquisition circuit includes resistor R35 and a filter network; resistor R35 is connected to the battery; resistor R35 is connected to the filter network; and the filter network is connected to the controller.

[0093] In this embodiment, the device uses a DC low-current discharge method to measure the battery internal resistance, which requires simultaneous acquisition of the discharge current and the voltage difference during discharge.

[0094] To accurately measure minute pressure difference changes, a four-wire Kelvin measurement method is used. BAT_C+ and BAT_C- are used to apply the discharge current, while BAT_U+ and BAT_U- are used to acquire the battery voltage and pressure difference.

[0095] The discharge circuit starts from the positive terminal BAT_C+ of the battery, passes through the magnetic latching relay K1, the anti-reverse diode D5, the discharge resistor R30, the discharge MOS switch Q1, and the sampling resistor R35 in sequence, and finally returns to the negative terminal BAT_C- of the battery.

[0096] During discharge, the controller calculates the discharge current by detecting the voltage across the sampling resistor R35. The voltage signal across R35 is then fed into the controller's differential ADC2 channel after passing through a filtering network.

[0097] In one embodiment, please refer to Figure 5The aforementioned internal resistance measurement discharge battery differential voltage acquisition circuit includes capacitors C35 and C39 and a filter network; the battery is connected to capacitors C35 and C39 respectively; capacitors C35 and C39 are connected to the filter network; and the filter network is connected to the controller.

[0098] In this embodiment, during the discharge process, a voltage difference signal with a certain frequency is generated between the two ends of the battery, BAT_U+ and BAT_U-. These signals are first filtered by capacitors C35 and C39 to remove the DC component.

[0099] The filtered signal is then processed by a filtering network and finally fed into the differential ADC1 channel of the MCU for analog-to-digital conversion.

[0100] The main function of setting up a magnetic latching relay K1 in the discharge circuit is to physically disconnect the discharge circuit when the MCU detects that the discharge MOS switch Q1 has failed and is out of control, thus ensuring the safe operation of the battery.

[0101] When the controller detects a failure of the discharge MOS switch, it will immediately disconnect the magnetic latching relay and report the discharge MOS switch failure so that timely measures can be taken.

[0102] This data acquisition circuit design comprehensively considers the accurate acquisition of multiple key parameters, including battery voltage, negative terminal temperature, internal resistance measurement, discharge current, and discharge voltage difference. Through reasonable circuit layout and signal processing, it ensures data accuracy and system reliability. Simultaneously, the inclusion of protective measures such as magnetic latching relays enhances the overall system's safety and stability.

[0103] In this embodiment, the controller includes a control chip U12. The control chip U12 is, but is not limited to, the MSP430AFE253.

[0104] The aforementioned acquisition circuit is used to measure four key signals: battery voltage, negative terminal temperature, internal resistance, discharge current, and internal resistance / discharge voltage difference. Measuring the battery's internal resistance using a low-current DC discharge method requires precise acquisition of the discharge current and voltage difference. During low-current discharge, the voltage change is extremely small; therefore, a 4-wire Kelvin measurement technique is used to improve measurement accuracy. The specific wiring is as follows: BAT_C+ and BAT_U+ are connected to the battery positive terminal, while BAT_C- and BAT_U- are connected to the battery negative terminal. BAT_C+ and BAT_C- are used to apply the discharge current, while BAT_U+ and BAT_U- are used to acquire the battery voltage and the voltage difference during discharge.

[0105] To monitor the temperature of the battery's negative terminal, an NTC (negative temperature coefficient) resistor is used for temperature measurement. The NTC resistor and resistor R23 form a voltage divider circuit, and the temperature information is reflected by detecting the voltage change across the NTC resistor. After being divided by R23 and the NTC resistor, the signal is filtered by capacitor C32 to eliminate unwanted noise interference. This processed temperature signal is then input to channel B0 of the two-to-one analog switch U10.

[0106] For battery voltage acquisition, the battery voltage is first divided using resistors R18 and R20, and then filtered using capacitor C28 to ensure signal stability. The processed battery voltage signal is then sent to channel B1 of analog switch U10.

[0107] The selection of analog switch U10 is controlled by the controller, which selects either battery voltage or negative terminal temperature signal for further processing as needed. The selected signal is buffered by voltage follower U11 to ensure signal quality, and after being processed by a filtering network, it is finally connected to the differential ADC0 channel of the controller to complete the analog-to-digital conversion.

[0108] During the discharge process for internal resistance measurement, a voltage difference at a certain frequency will occur across the battery terminals. These voltage differences are filtered by capacitors C35 and C39 to remove the DC component, then processed by a filter network, and finally fed into the differential ADC1 channel of the MCU.

[0109] The discharge circuit starts from the positive terminal BAT_C+ of the battery, passes sequentially through the magnetic latching relay K1, the reverse protection diode D5, the discharge resistor R30, the discharge MOS switch Q1, and the discharge current sampling resistor R35, and finally returns to the negative terminal BAT_C- of the battery. During the discharge process, the controller determines the magnitude of the discharge current by detecting the voltage across the sampling resistor R35. The voltage signal across R35 is processed by a filtering network and then input to the differential ADC2 channel of the controller.

[0110] The magnetic latching relay K1 is present to provide additional safety. When the controller detects that the discharge MOS switch Q1 has failed and is out of control, the controller can disconnect the magnetic latching relay, physically cutting off the discharge circuit, thereby ensuring the safe operation of the battery. Simultaneously, the controller will also report the fault condition of the discharge MOS switch failure so that timely countermeasures can be taken.

[0111] Through the detailed circuit design and protection mechanisms described above, the accurate acquisition of key parameters such as battery voltage, negative terminal temperature, internal resistance measurement discharge current, and discharge voltage difference is ensured, while improving the safety and stability of the system.

[0112] The device in this embodiment aims to monitor the individual cell voltage, internal resistance, and temperature of the battery, as well as the voltage and current of the entire battery pack, in real time through a network consisting of a concentrator 10 and multiple modules. The system employs automatic addressing technology to ensure that each module correctly corresponds to its respective battery pack, and can communicate with the user's host or monitoring platform via RS485 using the Modbus-RTU protocol or Ethernet port using the Modbus-TCP protocol, thereby enabling data reading and command issuance.

[0113] After the concentrator 10 is powered on, the acquisition bus interface provides 24V power to the connected modules via a network cable, and includes addressing signals and RS485 communication signals in the acquisition bus. These signals are used for cascaded communication between modules to ensure system continuity and consistency. In addition, the concentrator 10 supports setting 1 to 6 battery packs, each with a different COM port to facilitate accurate matching of battery pack information.

[0114] The automatic addressing function allows the concentrator 10 to automatically identify and assign addresses to each module without manual intervention. This process is accomplished through a daisy-chain method: first, all modules set their addresses to FFFF after receiving the broadcast command; then, the first module receives the Addr signal from the concentrator 10 and is assigned an address, subsequently sending the Addr signal to the next module, and so on until all modules are numbered. Once all modules in a certain path have been numbered, if no new addressing signal is received within a certain period, the numbering of modules in other paths begins.

[0115] For measuring the internal resistance of individual cells, a 4-wire Kelvin measurement method was used to improve accuracy. One pair of wires was used to apply the current, and the other pair was used to measure the voltage, thus eliminating the influence of wire resistance and contact resistance. The AD converter in the controller uses three 24-bit differential inputs, with one AD converter sharing the battery voltage and negative terminal temperature, and another AD converter using separate inputs for the discharge current and discharge voltage difference, ensuring measurement accuracy and safety.

[0116] To ensure the safe operation of the system, the MCU will take appropriate measures when an abnormality is detected. For example, if the battery voltage exceeds the reasonable range, the MCU will not operate the discharge circuit and will report a fault status. Additionally, if a sticking or short-circuit fault is detected in the internal resistance measurement discharge MOS, the controller will send a pulse signal to disconnect the magnetic latching relay, thereby cutting off the discharge circuit and ensuring battery safety.

[0117] During internal resistance measurement, the controller closes the internal resistance measurement discharge MOS according to the instructions of concentrator 10, and activates the AD converter to collect the discharge current and discharge voltage difference at the end of each closing and opening. Based on these data, the internal resistance value is calculated, as shown below:

[0118]

[0119] Wherein, Ri1, Ri2, ..., Rin represent the internal resistance value of the MCU after repeating the closing, opening, and discharging MOS action n times within a certain time period.

[0120] Riavg represents the average of n internal resistance measurements.

[0121] U11, U12, ..., U1n represent the discharge voltage values ​​collected each time the MOS is closed.

[0122] I11, I12, ..., I1n represent the discharge current values ​​collected each time the MOS is closed.

[0123] U21, U22, ..., U2n represent the disconnection voltage values ​​collected each time the MOS is disconnected.

[0124] I21, I22, ..., I2n represent the disconnection current values ​​collected each time the MOS is disconnected.

[0125] When the controller receives a data read command from the concentrator 10, it sends information including the currently collected battery voltage, negative terminal temperature, internal resistance parameters, and fault codes. If the controller fails to receive communication commands from the concentrator 10 for a certain period after power-on, it will determine a communication fault, and the module indicator light will change to a fault state. Simultaneously, the concentrator 10 will continuously monitor the module's communication status. If the concentrator 10 fails to read the module's communication data a certain number of times consecutively, it will send a module communication fault message to the user's host or monitoring platform.

[0126] To minimize the impact on battery capacity, the discharge current at any given time should be less than 1.5A.

[0127] In summary, this online battery monitoring and management system, through its sophisticated design and effective safety measures, not only achieves efficient monitoring of battery performance parameters but also significantly improves the system's reliability and safety.

[0128] The aforementioned online battery monitoring and management device, through the coordinated operation of the concentrator 10, the individual cell internal resistance module 20, the total voltage module 30, and the current module 40, achieves effective and accurate monitoring of the battery status. Specifically, the individual cell internal resistance module 20 integrates a controller, module bus interface, communication and automatic addressing isolation circuits, and acquisition circuits. It can collect key parameters such as battery voltage, negative terminal temperature, internal resistance measurement, discharge current, and voltage difference. Through its connection with the total voltage module 30 and the current module 40, it ensures accurate data transmission to the concentrator 10 for comprehensive analysis. The automatic addressing function simplifies the system configuration process, while the isolation circuit ensures the stability and security of data transmission. This design not only improves the accuracy of battery performance monitoring but also enhances the reliability and security of the DC backup power system in various application scenarios, thereby effectively preventing potential faults and ensuring the continuous and stable operation of the system.

[0129] In one embodiment, a method for operating the above-described online battery monitoring and management device is also provided, comprising:

[0130] The concentrator 10 provides a 24V power supply and uses the acquisition bus to transmit addressing signals and RS485 communication signals.

[0131] The concentrator 10 collects the voltage, internal resistance, and temperature information of each battery cell through the individual cell internal resistance module 20, monitors the overall voltage and current of the battery pack through the total voltage module 30 and the current module 40, and communicates with the user host or monitoring platform through Modbus-RTU or Modbus-TCP protocol to read data and issue commands.

[0132] Specifically, after power-on, the concentrator 10 uses its acquisition bus interface to provide 24V power to the modules via a network cable. The acquisition bus also includes addressing signals and RS485 communication signals. The number of battery packs can be set in the concentrator 10, and the concentrator 10 can automatically address the connected modules. After addressing, it can communicate with each module to collect information such as individual battery cell voltage, internal resistance, and temperature, as well as battery pack voltage and current. This comprehensive measurement determines the performance of the battery pack and the individual batteries, and provides timely warnings for battery faults and risks, ensuring safe battery operation. The user host or monitoring platform can communicate with the concentrator 10 via RS485 using the Modbus-RTU protocol, or via Ethernet using the Modbus-TCP protocol, to read relevant data and issue relevant commands.

[0133] The battery packs configured in concentrator 10 correspond to the acquisition bus COM ports, with a maximum of 6 battery packs. This ensures that the received data from the monitoring modules corresponds to the data from the battery pack. When building the system according to the battery online monitoring system architecture diagram, it is essential to ensure that the battery pack modules correspond to the assigned COM ports of concentrator 10. The following configurations are provided: Group 1: corresponds to all COM1-6 ports; Group 2: Group 1 corresponds to COM1-3, Group 2 corresponds to COM4-6; Group 3: Group 1 corresponds to COM1-2, Group 2 corresponds to COM3-4, Group 3 corresponds to COM5-6; Group 4: Groups 1-4 correspond to COM1-COM4, ​​COM5-6 are invalid; Group 5: Groups 1-5 correspond to COM1-COM5, COM6 is invalid; Group 6: Groups 1-6 correspond to COM1-6.

[0134] Automatic addressing ensures that the module information collected by the concentrator 10 corresponds to the battery cell, total voltage, current and other information of the battery pack, without the need for manual writing of module addresses.

[0135] The concentrator 10 communicates directly with the modules in a daisy-chain manner. The Addr_OUT signal in the COM interface of each acquisition bus of the concentrator 10 is connected to the Addr_IN of the COM_IN port of the first module in that channel. The Addr_OUT of the first COM_OUT port is connected to the Addr_IN of the COM_IN port of the second module in that channel, thus forming an automatic addressing line.

[0136] After receiving the automatic addressing instruction, the MCU of concentrator 10 sends an automatic addressing broadcast command via RS485, causing the addresses of all modules to become FFFF. After the controller of the first module receives the Addr signal from concentrator 10, concentrator 10 automatically numbers the first module. After setting, concentrator 10 causes the first module to output the Addr signal via RS485 command. After the second module receives the Addr signal, concentrator 10 automatically numbers the second module. In this way, all modules in the circuit can be automatically numbered.

[0137] After all modules on the first bus of concentrator 10 are automatically numbered, if no RS485 addressing signal is received from that module after a certain period of time, automatic addressing will begin for the modules connected to other buses until all modules are automatically numbered.

[0138] The controller in the single-cell internal resistance module 20 mainly collects the voltage of the battery cell, the temperature of the negative terminal, the discharge current for internal resistance measurement, and the voltage difference of the discharged battery. The internal resistance value can be obtained by dividing the discharge current by the voltage difference during the internal resistance test. To ensure the accuracy of internal resistance measurement, the single-cell module and the battery use a 4-wire Kelvin measuring lead, one pair for applying current and the other pair for measuring voltage. This eliminates the influence of the test lead set and contact resistance.

[0139] To ensure the accuracy of battery voltage, temperature, and internal resistance measurements, the selected controller uses a 3-channel 24-bit differential input AD converter, and the AD reference voltage uses an external low-temperature drift coefficient reference power supply. Battery voltage and negative terminal temperature share one AD converter channel via an analog switch, while the discharge current and discharge voltage difference for internal resistance measurements each use a separate channel.

[0140] The 24V power supply in the acquisition bus is stepped down to 5V to supply the RS485 communication circuit. At the same time, because the reference points of the batteries in the battery pack are different, in order to ensure measurement accuracy and safety, the 5V is supplied to the module's acquisition circuit through an isolated power supply.

[0141] After power-on, the MCU starts working, reading the battery voltage and negative terminal temperature.

[0142] If the battery voltage is outside the reasonable range, to ensure the safety of the battery and module, the controller will not take any action on the discharge circuit under any circumstances. At the same time, the controller will detect undervoltage or overvoltage faults in the battery and report the current fault status of the concentrator module 10. Simultaneously, the module indicator light will change to the fault status.

[0143] If the battery voltage is within a reasonable range, the controller closes the internal resistance measurement discharge MOS. If the AD converter detects a discharge current, the magnetic latching relay is correctly closed and requires no change. The internal resistance measurement discharge circuit is then considered normal, and the internal resistance measurement discharge MOS is disconnected. If the AD converter detects no discharge current, the controller sends a single pulse signal for a certain duration to change the magnetic latching relay to the closed state. If a discharge current is detected, the internal resistance measurement discharge circuit is considered normal, and the internal resistance measurement discharge MOS is then disconnected. If the AD converter still detects no discharge current, the controller determines that the internal resistance measurement discharge circuit is open-circuit faulted and reports the current fault status of module 10. Simultaneously, the module indicator light changes to a fault status.

[0144] At any given time, when the battery voltage is within a reasonable range, the magnetic latching relay is functioning normally, and the controller is in the state of disconnecting the internal resistance measurement discharge MOS, if the AD converter detects a discharge current exceeding the set threshold for a certain period of time, the controller determines that the internal resistance measurement discharge MOS is stuck or short-circuited (the internal resistance measurement discharge circuit is uncontrolled). It will then report the fault status of concentrator 10 and simultaneously send a single pulse signal for a certain duration to change the magnetic latching relay to the disconnected state, thus disconnecting the battery internal resistance monitoring discharge circuit and ensuring the safe and reliable operation of the battery. If the AD converter detects a discharge current at this time, the controller determines that the magnetic latching relay is faulty and will report the current fault status of concentrator 10 module. Simultaneously, the module indicator light will change to a fault status.

[0145] To reduce battery capacity loss, electrode material degradation and deformation during internal resistance measurement, and to extend battery life, the discharge current of the internal resistance measurement discharge circuit at any time is less than 1.5A.

[0146] When the battery voltage is within a reasonable range, after the controller receives the internal resistance measurement signal from the concentrator 10 and the magnetic latching relay of the internal resistance measurement discharge circuit is closed, the controller will close the internal resistance measurement discharge MOS at a certain frequency within a certain time. At the end of each closing and opening of the internal resistance measurement discharge MOS, the controller starts the corresponding AD to collect the discharge current and discharge voltage difference and calculates the internal resistance value according to the following formula:

[0147]

[0148] Wherein, Ri1, Ri2, ..., Rin represent the internal resistance value of the MCU after repeating the closing, opening, and discharging MOS action n times within a certain time period.

[0149] Riavg represents the average of n internal resistance measurements.

[0150] U11, U12, ..., U1n represent the discharge voltage values ​​collected each time the MOS is closed.

[0151] I11, I12, ..., I1n represent the discharge current values ​​collected each time the MOS is closed.

[0152] U21, U22, ..., U2n represent the disconnection voltage values ​​collected each time the MOS is disconnected.

[0153] I21, I22, ..., I2n represent the disconnection current values ​​collected each time the MOS is disconnected.

[0154] When the controller receives a data read command from the concentrator 10, it sends information including the currently collected battery voltage, negative terminal temperature, internal resistance parameters, and fault codes. If the controller does not receive a communication command from the concentrator 10 after a certain period of time after power-on, it will determine that there is a communication fault, and the module indicator light will change to a fault state. Simultaneously, the concentrator 10 will continuously monitor the module's communication status. If the concentrator 10 fails to read the module's communication data a certain number of times consecutively, it will send a module communication fault message to the user's host or monitoring platform.

[0155] The battery online monitoring and management device in this embodiment can effectively and accurately monitor the battery online, ensuring the reliability and safety of the battery DC backup power in various scenarios.

[0156] It should be noted that those skilled in the art can clearly understand that the specific implementation process of the above-mentioned battery online monitoring and management device can be referred to the corresponding description in the aforementioned device embodiments. For the sake of convenience and brevity, it will not be repeated here.

[0157] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A battery online monitoring and management device, characterized in that, include: The system comprises a concentrator, a single-cell internal resistance module, a total voltage module, and a current module; wherein the current module is connected to the total voltage module; the total voltage module is connected to the single-cell internal resistance module; the current module is connected to the concentrator; the single-cell internal resistance module includes a controller, a module bus interface, a communication and automatic addressing isolation circuit, and a data acquisition circuit; the communication and automatic addressing isolation circuit and the data acquisition circuit are respectively connected to the module bus interface; the data acquisition circuit is used to acquire battery voltage, negative terminal temperature, internal resistance measurement discharge current, and internal resistance measurement discharge battery voltage difference; the module bus interface is connected to the total voltage module; the controller is connected to the communication and automatic addressing isolation circuit and the data acquisition circuit respectively.

2. The online monitoring and management device for a storage battery according to claim 1, characterized in that, The module bus interface includes dual RJ45 ports.

3. The online monitoring and management device for a storage battery according to claim 1, characterized in that, The individual internal resistance module also includes a power isolation circuit; the power isolation circuit is connected to the module bus interface.

4. The online monitoring and management device for a storage battery according to claim 3, characterized in that, The power isolation circuit includes a TVS diode, a reverse protection diode D1, a step-down power supply U1, an isolation power chip U6, a linear regulator U7, and a reference power supply U4; the TVS diode is connected to the reverse protection diode D1; the reverse protection diode D1 is connected to the step-down power supply U1; the isolation power chip U6 is connected to the isolation transformer; the isolation transformer is connected to the linear regulator U7; and the linear regulator U7 is connected to the current module.

5. The online monitoring and management device for a storage battery according to claim 1, characterized in that, The communication and automatic addressing isolation circuit includes optocoupler U2, optocoupler U3, optocoupler U5, dual-channel digital isolator U9, and transceiver U8; the module bus interface is connected to the optocoupler U2; the controller is connected to the optocoupler U3; the optocoupler U3 is connected to the module bus interface; the controller is connected to the transceiver U8 through the optocoupler U5; the controller is connected to the dual-channel digital isolator U9; the dual-channel digital isolator U9 is connected to the transceiver U8; the transceiver U8 is connected to a common-mode inductor L2.

6. The online monitoring and management device for a storage battery according to claim 1, characterized in that, The acquisition circuit includes a battery voltage acquisition circuit, a negative electrode temperature acquisition circuit, an internal resistance measurement discharge current acquisition circuit, and an internal resistance measurement discharge battery differential pressure acquisition circuit; the battery voltage acquisition circuit, the negative electrode temperature acquisition circuit, the internal resistance measurement discharge current acquisition circuit, and the internal resistance measurement discharge battery differential pressure acquisition circuit are respectively connected to the controller.

7. The online monitoring and management device for a storage battery according to claim 6, characterized in that, The battery voltage acquisition circuit includes voltage divider resistors R18 and R20, filter capacitor C28, analog switch U10, voltage follower U11, and filter network. Voltage divider resistors R18 and R20 are connected to the battery. Voltage divider resistor R18 is connected to analog switch U10 via filter capacitor C28. Analog switch U10 is connected to the controller. Analog switch U10 is connected to voltage follower U11. Voltage follower U11 is connected to the filter network. The filter network is connected to the controller.

8. The online monitoring and management device for a storage battery according to claim 6, characterized in that, The negative electrode temperature acquisition circuit includes an NTC resistor, a voltage divider resistor R23, a filter capacitor C32, an analog switch U10, a voltage follower U11, and a filter network. The NTC resistor and the voltage divider resistor R23 are respectively connected to the battery. The NTC resistor is connected to the filter capacitor C32. The NTC resistor is connected to the analog switch U10. The analog switch U10 is connected to the controller. The analog switch U10 is connected to the voltage follower U11. The voltage follower U11 is connected to the filter network. The filter network is connected to the controller.

9. The online monitoring and management device for a storage battery according to claim 6, characterized in that, The internal resistance measurement discharge current acquisition circuit includes a resistor R35 and a filter network; the resistor R35 is connected to the battery; the resistor R35 is connected to the filter network; the filter network is connected to the controller; the individual internal resistance module includes a magnetic latching relay, and the magnetic latching relay is connected to the internal resistance measurement discharge current acquisition circuit.

10. A method of operating the online monitoring and management device for a storage battery as described in any one of claims 1 to 9, characterized in that, include: The concentrator provides 24V power and uses the acquisition bus to transmit addressing signals and RS485 communication signals. The concentrator collects voltage, internal resistance, and temperature information of each battery cell through the individual cell internal resistance module, monitors the overall voltage and current of the battery pack through the total voltage module and current module, and communicates with the user host or monitoring platform through Modbus-RTU or Modbus-TCP protocol to read data and issue commands.

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