Battery management system, battery management system and energy storage system
By moving the balancing resistor away from the cell management components and utilizing the thermally conductive connection components for heat dissipation, the problem of excessive local temperature rise in the battery pack is solved, improving the safety and accuracy of the battery system and reducing hardware costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SOLAR POWER NETWORK TECHNOLOGY (ZHEJIANG) CO LTD
- Filing Date
- 2025-05-12
- Publication Date
- 2026-05-29
AI Technical Summary
Traditional cell management systems can cause excessive localized temperature rises inside the battery pack during passive balancing, leading to safety risks.
The equalizing resistor is placed far away from the cell management component, and the connection component is used for rapid heat conduction and heat dissipation to prevent heat from being transferred to the cell management component and to keep the local temperature consistent with the overall temperature of the battery pack.
This reduces localized temperature rise inside the battery pack, improving safety, and allows for timely detection of problems through multi-frequency impedance measurement of individual cells, thus reducing hardware costs.
Smart Images
Figure CN224304718U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of battery management technology, and in particular to a cell management system, a battery management system, and an energy storage system. Background Technology
[0002] With the rise of the electric vehicle and energy storage industries, the market demand for energy storage systems is increasing, and the safety and lifespan of these systems are receiving significant attention. As a core component of energy storage systems, the cell management system continuously monitors relevant data from the battery cells and calculates various system parameters. For example, achieving charge balancing through cell monitoring can improve cell consistency and extend battery life. Therefore, the cell management system is an indispensable part of energy storage systems; the data it measures is used to ensure the energy storage system operates under safe conditions, thereby extending battery life and improving performance.
[0003] The cell management system in the related technology uses passive equalization to equalize the cell voltage and estimates the internal resistance based on the collected cell voltage and current, and then calculates various parameters of the system. Passive equalization is achieved through resistive heating.
[0004] However, the cell management system in the relevant technology cannot solve the problem of excessive local temperature rise inside the battery pack during passive balancing, which brings safety risks. Utility Model Content
[0005] Therefore, it is necessary to provide a cell management system, battery management system, and energy storage system that can solve the safety risks caused by excessive local temperature rise inside the battery pack during passive balancing.
[0006] A cell management system, comprising a cell body, a cell management component, and an equalization resistor; wherein:
[0007] The positive and / or negative terminals of the battery cell body are connected in series with adjacent battery cell bodies through corresponding connection components.
[0008] The cell management component is positioned close to the negative terminal of the cell body; the cell management component is electrically connected to the cell body and the equalization resistor; cell parameters are used for the cell body;
[0009] The equalizing resistor is positioned close to the positive terminal of the battery cell body; the equalizing resistor dissipates heat through the connecting assembly.
[0010] In one embodiment, the cell management system further includes a circuit board; wherein:
[0011] The circuit board extends from the positive terminal to the negative terminal of the battery cell body; the battery cell management component is disposed on the circuit board near the negative terminal of the battery cell body; the equalizing resistor is disposed on the circuit board near the positive terminal of the battery cell body; the battery cell management component and the equalizing resistor are connected by metal traces on the circuit board; the positive and / or negative terminals of the battery cell body are connected to the circuit board through corresponding connection components.
[0012] In one embodiment, the distance between the cell management component and the equalization resistor is greater than a preset safety distance.
[0013] In one embodiment, the cell management component is connected to an external device via a daisy-chain communication link.
[0014] In one embodiment, the connecting component is an aluminum busbar or a copper busbar.
[0015] The aforementioned cell management system places the balancing resistor on the positive terminal connection component of the cell body and the cell management component on the negative terminal connection component of the cell body. In this way, the balancing resistor is placed away from the cell management component, and the heat generated by the balancing resistor due to temperature rise is conducted and dissipated by the connection component, avoiding heat transfer to the cell management component. This makes the local temperature basically the same as the overall temperature of the battery pack, thereby reducing the local temperature rise inside the battery pack and improving safety.
[0016] A battery management system, the battery management system comprising a plurality of cell management systems as described in any one of the above and a first control device;
[0017] Multiple battery cell bodies corresponding to multiple battery cell management systems are connected in series;
[0018] Multiple battery cell management components corresponding to the multiple battery cell management systems are cascaded sequentially via wires; and the first-level battery cell management component and the last-level battery cell management component cascaded sequentially are respectively connected to the first control device;
[0019] The first control device is used to acquire the cell parameters of the cell body corresponding to each of the cell management systems.
[0020] The aforementioned battery management system, specifically the cell management system, addresses this by positioning the balancing resistors away from the cell management components and utilizing connection components to conduct and dissipate the heat generated by the balancing resistors due to temperature rise. This prevents heat transfer to the cell management components, ensuring that the local temperature remains essentially consistent with the overall battery pack temperature. This reduces localized temperature rise within the battery pack, improving safety. Furthermore, by placing cell management components on the negative terminal connection components of each cell, multi-frequency impedance measurements of individual cells can be performed, allowing for more timely detection of cell problems and further enhancing battery system safety. In addition, connecting all cells to the same control device saves costs.
[0021] In one embodiment, the cell management components are connected to each other via at least two daisy-chain communication links; the cell management components are also connected to the first control device via a daisy-chain communication link.
[0022] A battery management system includes a plurality of cell management systems as described in any one of the above claims, a first control device, and a second control device; wherein the plurality of cell management systems constitute at least one battery cluster; and each battery cluster is correspondingly provided with a second control device.
[0023] Within each battery cluster, multiple battery cells corresponding to multiple cell management systems are connected in series; multiple cell management components corresponding to multiple cell management systems are cascaded sequentially via wires; and the first-level cell management component and the last-level cell management component cascaded sequentially are respectively connected to the second control device; the second control device is used to acquire the cell parameters of each cell cell within the corresponding battery cluster.
[0024] The first control device is connected to multiple second control devices, and the first control device is used to acquire the cell parameters of all cell bodies.
[0025] The aforementioned battery management system, in its cell management system, sets the balancing resistors away from the cell management components and uses connection components to conduct and dissipate the heat generated by the balancing resistors due to temperature rise, avoiding heat transfer to the cell management components. This ensures that the local temperature is basically consistent with the overall temperature of the battery pack, thereby reducing the local temperature rise inside the battery pack and improving safety. In addition, for each cell, a cell management component is set on the negative terminal connection component of each cell, which can realize multi-frequency impedance measurement of individual cells, and detect cell problems more promptly, thereby improving the safety of the battery system.
[0026] In one embodiment, the cell management components within the same battery cluster are connected to each other via at least two daisy-chain communication links; the cell management components are connected to the second control device via a daisy-chain communication link; and the first control device and the second control device are connected via a bus link.
[0027] An energy storage system, the energy storage system comprising the battery management system described in any one of the above claims.
[0028] The aforementioned energy storage system, by setting the balancing resistor away from the cell management component and using the connection component to conduct and dissipate the heat generated by the balancing resistor due to temperature rise, avoids transferring heat to the cell management component. This ensures that the local temperature is basically consistent with the overall temperature of the battery pack, thereby reducing the local temperature rise inside the battery pack and improving safety. Furthermore, by setting the cell management component on the negative terminal connection component of each cell, multi-frequency impedance measurement of a single cell can be achieved, allowing for more timely detection of cell problems and thus improving the safety of the energy storage system. Attached Figure Description
[0029] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0030] Figure 1 The module structure of a battery cell management system is shown in one embodiment;
[0031] Figure 2 The module structure of the battery cell management system is shown in another embodiment;
[0032] Figure 3 The module structure of a battery management system is shown in one embodiment.
[0033] Figure 4 The module structure of a battery management system is shown in another embodiment;
[0034] Figure 5 The module structure of a battery management system is shown in another embodiment;
[0035] Figure 6 The module structure of a battery management system is shown in another embodiment;
[0036] Figure 7 The module structure of the battery management system is shown in another embodiment.
[0037] Explanation of reference numerals in the attached drawings: 100, cell body; 200, cell management component; 300, equalizing resistor; 101, positive terminal; 102, negative terminal; 400, connection component; 500, circuit board; 600, first control device; 700, second control device. Detailed Implementation
[0038] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.
[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.
[0040] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.
[0041] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.
[0042] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.
[0043] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.
[0044] With the rise of electric vehicles and the industrial and commercial energy storage industry, the market demand for energy storage systems is increasing, and the safety and lifespan of these systems are receiving significant attention. Many companies are investing heavily in research in this area. As a core component of energy storage systems, the cell management system continuously monitors cell data and calculates various system parameters. For example, measured voltage allows for the calculation of the system's remaining charge (SOC); measured temperature enables cooling control of the system's fans and provides early warning of thermal runaway; and cell equalization improves cell consistency and extends battery life. Therefore, the cell management system is an indispensable part of energy storage systems. The data it provides ensures that the energy storage system operates under safe conditions, thereby extending battery life and improving performance.
[0045] The cell management system corresponds to the battery management system, which mainly involves three technical fields: battery management technology, power electronics technology, and embedded system technology. Battery management technology mainly focuses on the management of parameters such as battery voltage, current, and temperature; power electronics technology mainly involves the driving and control of power devices; and embedded system technology mainly focuses on system software design and data processing.
[0046] Traditional cell management systems typically use a single chip to simultaneously measure the voltage and temperature of multiple cells. To maintain cell capacity consistency and improve battery cluster lifespan, passive equalization is usually employed to balance cell voltage. Passive equalization is achieved through resistor heating; the equalization resistors for each channel are typically clustered and laid flat on a hardware circuit board, with the number of channels potentially being 16. Furthermore, traditional cell management systems estimate internal resistance solely based on the collected cell voltage and current, and then calculate and predict a series of other parameters, such as state of equilibrium (SOH), thermal runaway, and micro-short circuits.
[0047] However, in traditional cell management technologies, the temperature on the surface of the equalization resistor rises rapidly during passive equalization. Due to the concentrated temperature rise, local temperatures can even reach 120°C within one minute, leading to excessively high localized temperatures within the battery pack and posing potential safety risks. Secondly, during the cell voltage plateau period, the small voltage change results in inaccurate internal resistance calculations, making it impossible to accurately estimate the cell's state of harm (SOH) and provide early warnings for other parameters. These inaccurate estimates may lead to incorrect repairs or misinterpret unsafe conditions as safe ones, resulting in unpredictable consequences.
[0048] To address the safety risk posed by excessively high surface temperature of the balancing resistor during passive balancing, which leads to excessive localized temperature rise within the battery pack, a cell management system was designed. By placing the balancing resistor at a location far from the cell management components and utilizing corresponding structural components for rapid heat conduction and dissipation, the system ensures accurate temperature measurement while preventing excessively high localized temperatures.
[0049] like Figure 1 As shown, a battery cell management system in one embodiment includes a battery cell body 100, a battery cell management component 200, and an equalizing resistor 300. The positive electrode 101 and / or negative electrode 102 of the battery cell body 100 are connected in series with adjacent battery cell bodies 100 via corresponding connecting components 400. The battery cell management component 200 is positioned close to the negative electrode 102 of the battery cell body 100. The battery cell management component 200 is electrically connected to the battery cell body 100 and the equalizing resistor 300. It is used to detect the battery cell parameters of the battery cell body 100. The equalizing resistor 300 is positioned close to the positive electrode 101 of the battery cell body 100. The equalizing resistor 300 dissipates heat through the connecting components 400.
[0050] The connecting component 400 may include a first connecting component disposed on the positive electrode 101 of the cell body 100 and a second connecting component disposed on the negative electrode 102 of the cell body 100. The first and second connecting components are made of the same material. The connecting component 400 may be an aluminum busbar or a copper busbar. The connecting component 400 may be installed on the positive electrode 101 or the negative electrode 102 by welding. In addition to welding, the connecting component 400 may also be installed by other existing methods, which will not be elaborated here. The specific installation method of the connecting component 400 is not limited here. The connecting component 400 is used to quickly conduct heat and dissipate heat from the balancing resistor 300, ensuring the accuracy of temperature measurement while avoiding the problem of excessive local temperature. In this embodiment, the connecting component 400 is described as an aluminum busbar. The cell management component 200 is disposed near the aluminum busbar of the negative electrode 102 of the cell body 100, and the balancing resistor 300 is disposed near the aluminum busbar of the positive electrode 101 of the cell body 100 and makes thermal contact with the aluminum busbar of the positive electrode 101.
[0051] The positive electrode 101 and / or negative electrode 102 of the cell body 100 are connected in series with adjacent cell bodies 100 through corresponding connection components 400. For example, there are n cell bodies 100 connected in series. The first cell body 100 has only the negative electrode 102 connected to the positive electrode 101 of the second cell body 100. From the second to the nth cell body, the positive electrode 101 of the current cell body 100 and the negative electrode 102 of the previous cell body 100 are connected in series through the connection components 400. The negative electrode 102 of the nth cell body 100 does not share the connection components 400 with other cells.
[0052] The cell management component 200, which can also be a cell management chip, can acquire the real-time status of each cell, obtain the cell parameters of each cell, and realize passive equalization, multi-frequency impedance measurement, and monitoring of the status of each cell. The principle of electrochemical impedance spectroscopy (EIS) measurement is to apply a small-amplitude sinusoidal voltage (or current) signal to the electrochemical system and measure the system's response to obtain its impedance characteristics. Specifically, EIS measures the system's resistance and capacitance response to AC signals of different frequencies. This function can be fully implemented by the cell management chip to obtain the Nyquist curve of the cell. Internally, it uses switches, resistors, and other components within the chip to form a current source. This current source applies a current to the cell, and the chip can measure the impedance at a specified frequency point. The measurement range can reach up to 10Hz to 7.81kHz. Therefore, multi-frequency impedance measurement can accurately estimate the cell's internal resistance, unaffected by voltage plateau periods. Cell parameters include, but are not limited to, temperature, voltage, and internal resistance. The chip model of the battery management chip can be, but is not limited to, DNB110xB.
[0053] The balancing resistor 300 can be determined by connecting multiple resistors in series and parallel. For example, it can be based on four resistors connected in series in pairs, and then the resulting series resistors connected in parallel. For instance, the balancing resistor 300 could be four 5R10 resistors connected in series and parallel, with an equivalent resistance of 5 ohms. This method, compared to directly using a 5-ohm balancing resistor 300, takes into account time and power consumption. Directly using a balancing resistor 300 with the target resistance value requires custom manufacturing, which is more time-consuming than connecting multiple resistors in series and parallel, and also carries the risk of overheating and damage due to power consumption.
[0054] In the aforementioned cell management system, the balancing resistor 300 is positioned near the connection component 400 of the positive terminal 101 of the cell body 100 and in thermally conductive contact with the connection component 400. The cell management component 200 is positioned near the connection component 400 of the negative terminal 102 of the cell body 100. This arrangement keeps the balancing resistor 300 away from the cell management component 200, and the connection component 400 conducts and dissipates the heat generated by the balancing resistor 300 due to temperature rise, preventing heat transfer to the cell management component 200. This ensures that the local temperature remains essentially the same as the overall battery pack temperature, thereby reducing local temperature rise within the battery pack and improving safety. Furthermore, by placing a cell management chip on each cell, accurate measurement of each cell can be performed, increasing the capacity of a single cell. With the total system capacity remaining constant, the number of cells used can be reduced, lowering hardware costs.
[0055] In one exemplary embodiment, such as Figure 2As shown, the cell management system also includes a circuit board 500; wherein: the circuit board 500 extends from the positive terminal 101 to the negative terminal 102 of the cell body 100; the cell management component 200 is disposed on the circuit board 500 near the negative terminal 102 of the cell body 100; the balancing resistor 300 is disposed on the circuit board 500 near the positive terminal 101 of the cell body 100; the cell management component 200 and the balancing resistor 300 are connected by metal traces on the circuit board 500. The positive terminal 101 and / or the negative terminal 102 of the cell body 100 are connected to the circuit board 500 through corresponding connection components 400.
[0056] The circuit board 500 can be a printed circuit board (PCB). The cell management component 200 is located on the end of the circuit board 500 near the negative terminal 102 of the cell body 100. This can be understood as the pins of the cell management component 200 being soldered to corresponding positions on the end of the circuit board 500 near the negative terminal 102 of the cell body 100. The balancing resistor 300 is located on the end of the circuit board 500 near the positive terminal 101 of the cell body 100. This can be understood as the pins of the balancing resistor 300 being soldered to corresponding positions on the end of the circuit board 500 near the positive terminal 101 of the cell body 100. The circuit board 500 is also connected to the connection components 400 of the positive terminal 101 and negative terminal 102 of the cell body 100 via soldering points at both ends.
[0057] The circuit board 500 contains a switch that can be controlled to open and close by receiving control signals from the switch, thereby turning the equalizing resistor on or off. It should be noted that the control methods between the cell management component, the equalizing resistor, and the circuit board 500 can be implemented using existing methods, which will not be elaborated upon here.
[0058] In the above method, the equalizing resistor 300 makes thermal contact with the positive terminal of the battery cell body 100 through the PCB, which can further improve the heat dissipation performance and reduce the impact of overheating.
[0059] In one exemplary embodiment, the distance between the cell management component 200 and the balancing resistor 300 is greater than a preset safety distance. This preset safety distance can be the distance between the positive and negative terminals of the cell. By ensuring the distance between the cell management component 200 and the balancing resistor 300 is greater than the preset safety distance, heat transfer can be prevented, thus improving safety.
[0060] In one exemplary embodiment, the cell management component 200 is connected to an external device via a daisy-chain communication link. This external device can be, but is not limited to, a control device (e.g., a chip), which can aggregate data from all cells and transmit information such as temperature, voltage, and internal resistance to a backend platform for processing and analysis via a CAN bus.
[0061] Furthermore, the following is a connection diagram of multiple of the above-mentioned cell management systems, with the connection of two adjacent cell bodies as an example, such as... Figure 3 As shown, the positive electrode 101 and / or negative electrode 102 of the cell body 100 are connected in series with other cell bodies 100 through the connecting component 400; the cell management component 200 is disposed at the negative electrode 102 of the cell body 100; the cell management component 200 is electrically connected to the cell body 100 and the equalizing resistor 300; it is used to detect the cell parameters of the cell body 100; the equalizing resistor 300 is disposed at the positive electrode 101 of the cell body 100; the equalizing resistor 300 is used for heat dissipation through the connecting component 400.
[0062] The circuit board 500 extends from the positive terminal 101 to the negative terminal 102 of the battery cell body 100. The battery cell management component 200 is disposed on the circuit board 500 near the negative terminal 102 of the battery cell body 100. The balancing resistor 300 is disposed on the circuit board 500 near the positive terminal 101 of the battery cell body 100. The battery cell management component 200, the battery cell body 100, and the balancing resistor 300 are connected by metal traces on the circuit board 500. The battery cell management component 200 is cascaded and connected to an external device via the circuit board 500 through two communication links (e.g., daisy-chain communication links).
[0063] This cell management system, with its connection method, places the balancing resistors away from the cell management chip, effectively reducing the surface temperature of the balancing resistors and avoiding safety risks caused by excessive localized temperature rise. Furthermore, when upgrading from small-capacity to large-capacity cells, the number of cells used can be reduced while maintaining the same total capacity, thus saving costs. Simultaneously, by placing a cell management component on each cell, precise measurement of temperature and voltage, as well as passive balancing and multi-frequency impedance measurement, can be achieved for each cell. This significantly improves the accuracy of battery parameter calculations and battery safety. Consequently, in the event of a cell malfunction, the faulty cell can be quickly located and replaced, reducing maintenance costs and improving the efficiency and reliability of battery management.
[0064] like Figure 4As shown, a battery management system is provided, which includes multiple cell management systems (as described above) and a first control device 600; multiple cell bodies 100 corresponding to the multiple cell management systems are connected in series; multiple cell management components 200 corresponding to the multiple cell management systems are cascaded sequentially via wires; and the first-stage cell management component 200 and the last-stage cell management component 200 cascaded sequentially are respectively connected to the first control device 600; the first control device 600 is used to acquire the cell parameters of the cell body 100 corresponding to each cell management system.
[0065] The specific structure and connection method of the cell management system can be implemented as described above, and will not be repeated here. The first control device 600 can be a control chip such as an MCU or CPU. The control chip model can be GD32F470VIT6 or STM32H743VITx. This chip can directly collect data from all cells, perform preliminary data calculations on the collected data such as temperature, voltage, and internal resistance, such as calculating SOX (State of X, the state of the battery in the battery management system), and transmit the cell internal resistance data to the back-end platform via Ethernet. Then, using AI algorithms, the SOX is further calculated to improve the calculation accuracy, and thermal runaway warnings are given based on temperature information. It can also perform micro-short circuit warnings based on internal resistance information, comprehensively judging whether the cell has a warning.
[0066] If an early warning is issued, a corresponding warning message will be sent. Users can then take appropriate actions based on the warning message, such as sending the battery for inspection and repair. The warning message is accurate down to the cell level, replacing the specific faulty cell instead of the entire battery pack, thus reducing costs. SOX encompasses various battery state parameters, such as SOC (State of Charge), SOH (State of Health), SOP (State of Power), and SOE (State of Energy).
[0067] The cell management components 200 are cascaded in sequence by wires. The wires can be used to connect the circuit boards 500 corresponding to the cell management components 200, or they can be set in other ways to enable the cell management components 200 to be cascaded in sequence. Here, there is no specific limitation on the setting of the wires.
[0068] The aforementioned battery management system, in its cell management system, sets the balancing resistor 300 away from the cell management component 200, and uses the connection component 400 to conduct and dissipate the heat generated by the balancing resistor 300 due to temperature rise, avoiding heat transfer to the cell management component 200. This ensures that the local temperature is basically consistent with the overall temperature of the battery pack, thereby reducing the local temperature rise inside the battery pack and improving safety. Furthermore, for each cell, a cell management component 200 is set on the negative terminal 102 connection component 400 of each cell, which can realize multi-frequency impedance measurement of a single cell, more timely detection of problems in each cell, and location of abnormal cells, thereby improving the safety of the battery system. In addition, connecting all cells to the same control device saves costs.
[0069] In one exemplary embodiment, the cell management components 200 are connected to each other via at least two daisy-chain communication links; the cell management components 200 are connected to the first control device 600 via a daisy-chain communication link.
[0070] Furthermore, to improve the stability of daisy-chain communication, a daisy-chain communication link (SPI) is reserved between the first control device 600 and the battery management chip. Under normal circumstances, data is transmitted and received through the first daisy-chain communication link SPI1. If a daisy-chain communication link (SPI) between chips is broken, the slave controller will transmit and receive data with the broken battery management chip through the second daisy-chain communication link SPI2, while simultaneously issuing an alarm to prompt the user to request maintenance. Figure 5 The battery management system shown includes the aforementioned multiple cell management systems and a first control device 600. There are 250 cell management systems, corresponding to 250 cell bodies. The 250 cell bodies 100 are connected in series via aluminum busbars. The first-level cell management component and the last-level cell management component, which are cascaded in series, are respectively connected to the first control device 600. The cell management components are connected to each other through at least two daisy-chain communication links, forming a ring-shaped communication link. The cell management components and the first control device 600 can communicate based on the at least two daisy-chain communication links to realize data transmission and reception.
[0071] like Figure 6As shown, a battery management system is provided, comprising multiple cell management systems (as described above), a first control device 600, and a second control device 700. The multiple cell management systems constitute at least one battery cluster. Each battery cluster is correspondingly equipped with a second control device 700. Within each battery cluster, multiple cell bodies 100 corresponding to the multiple cell management systems are connected in series. Multiple cell management components 200 corresponding to the multiple cell management systems are cascaded sequentially via wires. The first-level cell management component 200 and the last-level cell management component 200 cascaded sequentially are respectively connected to the second control device 700. The second control device 700 is used to acquire the cell parameters of each cell body 100 within the corresponding battery cluster. The first control device 600 is connected to multiple second control devices 700 and is used to acquire the cell parameters of all cell bodies 100. The number of cell bodies in a battery cluster is m, where m is a positive integer, and m can be 8.
[0072] The second control device 700 aggregates data from all cells in its corresponding battery cluster and transmits information such as temperature, voltage, and internal resistance to the backend platform, such as the first control device 600, via CAN. The first control device 600 obtains cell voltage, temperature, and internal resistance values at different frequency points by issuing commands through a daisy-chain communication link. Taking obtaining the internal resistance value as an example, the first control device 600 issues commands for the frequency value and internal resistance measurement, which are sequentially transmitted to each cell management chip via the daisy-chain communication link. After each management chip measures the internal resistance value at that frequency point, it transmits the data back to the first control device 600 via an SPI daisy-chain after being aggregated by the second control device 700.
[0073] Furthermore, after the first control device 600 aggregates all battery cluster information, it performs preliminary data calculations (such as calculating SOX) and transmits data such as cell internal resistance to the backend platform via Ethernet. Then, using AI algorithms, it further calculates SOX to improve accuracy, provides thermal runaway warnings based on temperature information, and micro-short circuit warnings based on internal resistance information, comprehensively assessing whether any warnings exist for the battery cells. If a warning exists, corresponding warning information is issued. Users then take appropriate actions based on the warning information, such as sending the battery for inspection and repair, or replacing the specific cell based on the cell-level warning information, rather than replacing the entire battery cluster.
[0074] The aforementioned battery management system, in its cell management system, sets the balancing resistors away from the cell management components and uses connection components to conduct and dissipate the heat generated by the balancing resistors due to temperature rise, avoiding heat transfer to the cell management components. This ensures that the local temperature is basically consistent with the overall temperature of the battery pack, thereby reducing the local temperature rise inside the battery pack and improving safety. In addition, for each cell, a cell management component is set on the negative terminal connection component of each cell, which can realize multi-frequency impedance measurement of individual cells, and detect cell problems more promptly, thereby improving the safety of the battery system.
[0075] In one exemplary embodiment, cell management components 200 within the same battery cluster are connected via at least two daisy-chain communication links; the cell management components 200 are connected to the second control device 700 via a daisy-chain communication link; and the first control device 600 and the second control device 700 are connected via a bus link. Figure 7 As shown, in Figure 6 Based on the above, the cell management components 200 are connected via at least two daisy-chain communication links. In this configuration, by setting up at least two daisy-chain communication links, if a communication link between a cell and the second control device 700 fails and data transmission and reception are impossible, data transmission and reception can be achieved through the other communication link, ensuring data integrity and simultaneously generating a corresponding alarm to prompt the user for maintenance.
[0076] It should be noted that in the aforementioned battery management system, if both a first control device and a second control device exist, the first control device can be GD32F407VIT6, and the second control device can be GD32F303CBT6. If only a first control device exists in the aforementioned battery management system, the first control device can be GD32F470VIT6 or STM32H743VITx.
[0077] It is understood that the aforementioned cell management system, battery management system, and energy storage system can also take other forms, and are not limited to the forms already mentioned in the above embodiments, as long as they can achieve the function of solving the problem of excessive local temperature rise inside the battery pack during passive balancing, thereby causing safety risks.
[0078] In one exemplary embodiment, an energy storage system including any of the above-described battery management systems is provided. The specific structure and functions can be implemented in the manner described in the above embodiments, and will not be repeated here.
[0079] The above system can be applied to energy storage power systems such as battery-powered hydropower, thermal power, wind power and solar power plants, as well as electric vehicles such as electric bicycles, electric motorcycles and electric cars that use batteries.
[0080] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.
[0081] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0082] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.
Claims
1. A cell management system, characterized in that, The cell management system includes a cell body, a cell management component, and an equalization resistor; wherein: The positive and / or negative terminals of the battery cell body are connected in series with adjacent battery cell bodies through corresponding connection components. The cell management component is positioned close to the negative terminal of the cell body; the cell management component is electrically connected to the cell body and the equalization resistor; and is used to detect the cell parameters of the cell body. The equalizing resistor is positioned close to the positive terminal of the battery cell body; the equalizing resistor dissipates heat through the connecting assembly.
2. The cell management system according to claim 1, characterized in that, The cell management system further includes a circuit board; wherein: The circuit board extends from the positive terminal to the negative terminal of the battery cell body; the battery cell management component is disposed on the circuit board near the negative terminal of the battery cell body; the equalizing resistor is disposed on the circuit board near the positive terminal of the battery cell body; the battery cell management component and the equalizing resistor are connected by metal traces on the circuit board; the positive and / or negative terminals of the battery cell body are connected to the circuit board through corresponding connection components.
3. The cell management system according to claim 1, characterized in that, The distance between the cell management component and the equalization resistor is greater than a preset safety gap.
4. The cell management system according to any one of claims 1 to 3, characterized in that, The cell management component is connected to external devices via a daisy-chain communication link.
5. The cell management system according to claim 4, characterized in that, The connecting component is an aluminum busbar or a copper busbar.
6. A battery management system, characterized in that, The battery management system includes a plurality of cell management systems as described in any one of claims 1 to 5 and a first control device; Multiple battery cell bodies corresponding to multiple battery cell management systems are connected in series; Multiple battery cell management components corresponding to the multiple battery cell management systems are cascaded sequentially via wires; and the first-level battery cell management component and the last-level battery cell management component cascaded sequentially are respectively connected to the first control device; The first control device is used to acquire the cell parameters of the cell body corresponding to each of the cell management systems.
7. The battery management system according to claim 6, characterized in that, The cell management components are connected to each other via at least two daisy-chain communication links; the cell management components are connected to the first control device via a daisy-chain communication link.
8. A battery management system, characterized in that, The battery management system includes multiple cell management systems as described in any one of claims 1 to 5, a first control device, and a second control device; wherein the multiple cell management systems constitute at least one battery cluster; and each battery cluster is correspondingly provided with a second control device. Within each battery cluster, multiple battery cells corresponding to multiple cell management systems are connected in series; multiple cell management components corresponding to multiple cell management systems are cascaded sequentially via wires; and the first-level cell management component and the last-level cell management component cascaded sequentially are respectively connected to the second control device; the second control device is used to acquire the cell parameters of each cell cell within the corresponding battery cluster. The first control device is connected to multiple second control devices, and the first control device is used to acquire the cell parameters of all cell bodies.
9. The battery management system according to claim 8, characterized in that, The cell management components within the same battery cluster are connected to each other via at least two daisy-chain communication links; the cell management components are connected to the second control device via a daisy-chain communication link; and the first control device and the second control device are connected via a bus link.
10. An energy storage system, characterized in that, The energy storage system includes the battery management system as described in any one of claims 6 to 9.