Battery management system

Abstract

The embodiment of the utility model provides a battery management system which is applied to a battery pack, the battery pack is installed on a gardening tool, and the battery management system comprises a charging circuit, a discharging circuit, a charging interface and a discharging interface; wherein the charging circuit comprises a charging control electronic switch and is used for performing charging control on a battery pack; the discharging circuit comprises a discharging control electronic switch and is used for performing discharging control on the battery pack, the specification of the discharging control electronic switch is different from that of the charging control electronic switch, and the discharging control electronic switch and the charging control electronic switch do not share one current loop; the charging interface and the discharging interface are different interfaces. Through application of the method and the device, the problem of low charging efficiency caused by unnecessary power loss in the charging process of the battery pack in a battery management system in the related technology is solved, and the effect of improving the charging efficiency of the battery pack is further achieved.

Description

Technical Field

[0001] This application relates to the field of garden tools, and more specifically, to a battery management system. Background Technology

[0002] In a Battery Management System (BMS), the battery pack's cells need to be protected against overcharging and over-discharging. Existing garden tools cover different power levels, such as chainsaws (>1000W), hedge trimmers (300-500W), and hair dryers (800-1200W). However, in the garden tool industry, all tool categories share a common platform, and different tools operate under different conditions. Existing BMS designs discharge protection thresholds (e.g., 20A continuous discharge) based on the highest power equipment (e.g., a 1500W chainsaw), requiring the battery pack to be designed for over-discharge protection based on the highest power equipment. Redundancy protection margins are still maintained for lower power equipment, resulting in system efficiency loss. Furthermore, the battery pack's charging and discharging circuits are consistent, and the charging process needs to maintain the on-resistance corresponding to the high-current discharge capability. In practice, due to thermal derating, a larger conduction area needs to be maintained, leading to a 30-50% increase in switching losses, thus reducing overall efficiency.

[0003] Therefore, it can be seen that the battery management system in the relevant technology has the problem of low charging efficiency due to unnecessary power loss during the charging process of the battery pack. Utility Model Content

[0004] This application provides a battery management system to at least solve the problem of low charging efficiency caused by unnecessary power loss during the charging process of the battery pack in the related art.

[0005] According to one aspect of the embodiments of this application, a battery management system is provided, applied to a battery pack installed on a garden tool. The battery management system includes: a charging line, a discharging line, a charging interface, and a discharging interface. The charging line includes a charging control electronic switch for controlling the charging of the battery pack. The discharging line includes a discharging control electronic switch for controlling the discharging of the battery pack. The specifications of the discharging control electronic switch are different from those of the charging control electronic switch, and the discharging control electronic switch and the charging control electronic switch do not share a current loop. The charging interface and the discharging interface are different interfaces. The charging line and the discharging line are completely separated. Using electronic switches of different specifications avoids mutual interference caused by differences in current and voltage characteristics during charging and discharging. The switch specifications match their respective scenarios, reducing energy conversion losses, distributing power device layout, and separating charging and discharging heat sources to form independent heat dissipation lines, thus avoiding heat accumulation.

[0006] In an exemplary embodiment, both the charging control electronic switch and the discharging control electronic switch are MOSFETs. The battery management system further includes a system control module for controlling the charging control electronic switch and the discharging control electronic switch. The system control module is connected to the gate of the charging control electronic switch and the gate of the discharging control electronic switch. The source of the charging control electronic switch is connected to the charging interface, and its drain is connected to the positive terminal of the battery pack. The source of the discharging control electronic switch is connected to the discharging interface, and its drain is connected to the positive terminal of the battery pack. Using MOSFETs as charging control electronic switches provides low on-resistance, fast switching response, and high efficiency. Controlling the charging and discharging process by the system control module improves the control over the battery pack's charging and discharging process and enhances its safety.

[0007] In one exemplary embodiment, there are two charging control electronic switches. The source of the first charging control electronic switch is connected to the charging interface, the drain is connected to the source of the second charging control electronic switch, and the gate is connected to the system control module. The drain of the second charging control electronic switch is connected to the positive terminal of the battery pack, and the gate is connected to the system control module. The design of dual charging control electronic switches can reduce the need for high-specification components (which are usually more expensive) on the charging line, thereby reducing component costs. It can also achieve fine control of the charging line. The independent gate control mechanism of the dual switches allows the system control module to flexibly adjust the charging strategy, adapt to different charging conditions, optimize charging efficiency, and extend battery life.

[0008] In one exemplary embodiment, the battery management system further includes a step-down circuit disposed between the positive terminal of the battery pack and the system control module, for reducing the voltage of the battery pack to the supply voltage of the system control module. The step-down circuit, disposed between the positive terminal of the battery pack and the system control module, improves voltage matching between the battery pack and the system control module, increases energy conversion efficiency, enhances system thermal management and safety, and ensures stable and efficient operation of the battery management system.

[0009] In an exemplary embodiment, the battery management system further includes: a first communication module and a status detection module; wherein the first communication module is electrically connected to a data bus and is used as a slave to receive data sent by a master; the status detection module is connected to the system control module and is used to detect the status of the battery pack and transmit the detected battery pack status data to the system control module, wherein the battery pack status data includes the battery pack voltage data; the system control module is further used to send the battery pack status data to the data bus through the first communication module. Through real-time monitoring and intelligent data communication, the safety and intelligence of the battery management system are improved. This design optimizes battery use, reduces maintenance costs, and enhances equipment performance and service life.

[0010] In one exemplary embodiment, the battery management system further includes a temperature detection circuit connected to the state detection module, used to detect the battery pack temperature and upload the detected battery pack temperature data to the state detection module. The battery pack state data also includes the battery pack temperature data. By monitoring the battery pack temperature in real time, the charging and discharging strategy can be dynamically adjusted to avoid battery performance degradation and safety risks caused by excessively high or low temperatures. Furthermore, the temperature data can also be used to predict the battery pack's lifespan and provide early warnings of potential thermal runaway risks, thereby improving the safety and reliability of the entire system.

[0011] In an exemplary embodiment, the battery management system further includes a current-sensing resistor connected to the state detection module and the negative terminal of the battery pack; wherein the state detection module is further configured to perform current detection on the battery pack through the current-sensing resistor to obtain battery pack current data, wherein the battery pack state data also includes battery pack current data. Obtaining the battery pack current data through the current-sensing resistor helps the system to detect faults such as overcurrent and short circuit in a timely manner, improves the efficiency of fault diagnosis and handling, and ensures the safe operation of the battery pack.

[0012] In an exemplary embodiment, the battery management system further includes a second communication module and a third communication module; wherein the second communication module is electrically connected to the data bus and is used to passively receive bus data from the data bus and transmit the received bus data to the third communication module; the third communication module is connected to the system control module and is used to establish a connection with a terminal device, obtain data requested by the terminal device through the data bus, and transmit the data requested by the terminal device to the terminal device; the third communication module is a wireless module. Introducing the second communication module as a data transmission relay can effectively reduce the data processing pressure on the system control module and improve the efficiency and reliability of data transmission; separating the functions of data transmission and wireless communication from the system control module and having them undertaken by a dedicated communication module helps optimize the internal resource allocation of the system, allowing the system control module to focus on core battery management tasks and improve the overall performance of the system.

[0013] In one exemplary embodiment, the battery management system further includes: a prompting component connected to the system control module, used to prompt the status of the battery pack under the control of the system control module. Integrating the prompting component into the device upgrade system and having it prompt the status of the battery pack can enhance the interactivity and security of the system, allowing users to understand the status of the battery pack through intuitive prompts, take timely and correct actions, and ensure the stable operation of the battery system.

[0014] In an exemplary embodiment, both the charging control electronic switch and the discharging control electronic switch are MOSFETs; the specifications of the discharging control electronic switch are higher than those of the charging control electronic switch, and a fuse is provided between the source of the discharging control electronic switch and the discharging interface. The addition of the fuse provides an extra layer of safety protection for the device upgrade system, enabling it to respond quickly to abnormal current, prevent safety issues such as cell overheating and short circuits, and improve the safety of the system under high-power discharge conditions.

[0015] This application utilizes a method that separates the charging and discharging circuits, allowing the battery pack to be installed on garden tools. The battery management system of the battery pack includes charging and discharging circuits, with different interfaces for charging and discharging (different ports for charging and discharging). The charging control electronic switch on the charging circuit controls the charging process of the battery pack, while the discharging control electronic switch on the discharging circuit controls the discharging process. Since the specifications of the discharging control electronic switch are different from those of the charging control electronic switch, and the discharging control electronic switch and the charging control electronic switch do not share a current loop, the charging process does not need to maintain the on-resistance corresponding to the high current discharge capacity. This reduces unnecessary power loss during charging, achieving the goal of reducing switching losses and improving charging efficiency. This solves the problem of low charging efficiency caused by unnecessary power loss during the charging process in related battery management systems. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of an optional battery management system according to an embodiment of this application;

[0017] Figure 2 This is a schematic diagram of another optional battery management system according to an embodiment of this application;

[0018] Figure 3 This is a schematic diagram of another optional battery management system according to an embodiment of this application;

[0019] Figure 4 This is a schematic diagram of another optional battery management system according to an embodiment of this application;

[0020] Figure 5 This is a schematic diagram of another optional battery management system according to an embodiment of this application;

[0021] Figure 6 This is a schematic diagram of another optional battery management system according to an embodiment of this application;

[0022] Figure 7 This is a schematic diagram of another optional battery management system according to an embodiment of this application;

[0023] Figure 8 This is a schematic diagram of another optional battery management system according to an embodiment of this application;

[0024] Figure 9 This is a schematic diagram of another optional battery management system according to an embodiment of this application;

[0025] Figure 10This is a schematic diagram of another optional battery management system according to an embodiment of this application;

[0026] Figure 11 This is a schematic diagram of another optional battery management system according to an embodiment of this application.

[0027] The above figures include the following reference numerals:

[0028] Charging circuit 101, discharging circuit 102, charging interface 103, discharging interface 104, charging control electronic switch 1011, discharging control electronic switch 1021;

[0029] System control module 301;

[0030] Step-down circuit 401;

[0031] First communication module 501, status detection module 702;

[0032] Temperature detection circuit 601;

[0033] Current sensing resistor 701;

[0034] Second communication module 801, third communication module 802;

[0035] Prompt component 901. Detailed Implementation

[0036] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0037] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, including a series of systems, products, or devices is not necessarily limited to those explicitly listed, but may include other steps or units not explicitly listed or inherent to these products or devices.

[0038] According to one aspect of the embodiments of this application, a battery management system is provided, which can be integrated into a battery pack. In the garden tool industry, battery packs are widely used as a power source in various tools, covering tools with different power levels such as chainsaws (>1000W), hedge trimmers (300-500W), and hair dryers (800-1200W). In a BMS, it is necessary to shut down and protect the battery pack cells from overcharging and over-discharging. However, in the garden tool industry, all types of tools share a common platform, and different tools operate under different conditions. Existing BMSs are designed with discharge protection thresholds (e.g., 20A continuous discharge) based on the highest power equipment (e.g., a 1500W chainsaw), which means that the battery pack needs to be designed for over-discharge protection based on the highest power equipment, while retaining redundant protection margins for low-power equipment, resulting in a loss of system efficiency. However, the charging and discharging circuits of the battery pack are consistent, and the charging process needs to maintain the on-resistance corresponding to the high current discharge capacity. In practice, due to thermal derating, a larger conduction area needs to be maintained, resulting in a 30-50% increase in switching losses, thereby reducing overall efficiency.

[0039] To at least partially solve the above problems, the charging and discharging circuits are separated, the specifications of the discharge control electronic switch are different from those of the charging control electronic switch, and the discharge control electronic switch and the charging control electronic switch do not share a current loop. The charging process does not need to maintain the on-resistance corresponding to the high current discharge capacity, thereby reducing switching losses and improving overall efficiency.

[0040] The battery management system in this embodiment can be applied to a battery pack, which is installed on garden tools. Figure 1 This is a schematic diagram of an optional battery management system according to an embodiment of this application, such as... Figure 1 As shown, the battery management system includes: a charging line 101, a discharging line 102, a charging interface 103, and a discharging interface 104; wherein, the charging line 101 includes a charging control electronic switch 1011 for controlling the charging of the battery pack; the discharging line 102 includes a discharging control electronic switch 1021 for controlling the discharging of the battery pack; the charging interface 103 and the discharging interface 104 are different interfaces. Here, all parts of the battery management system can be located within the battery pack.

[0041] Charging line 101 refers to the entire circuit path through which current flows from a power source (e.g., charger, grid, or solar panel) through the BMS to the battery pack during charging. Charging line 101 may include multiple circuit components, such as charging interface 103 and charging control electronic switch 1011, and may also include other necessary components or circuits, such as protection circuits and the final charging path to the battery. Discharging line 102 refers to the circuit path through which current flows from the battery pack through a series of circuit components to the load when the battery pack provides power to the load (e.g., chainsaw, hedge trimmer, hair dryer, etc.). Discharging line 102 may include multiple circuit components, such as discharge control electronic switch 1021 and discharge interface 104, and may also include other necessary components or circuits, such as protection circuits and electrical connections between the battery pack and the load.

[0042] Various electronic components can be used as electronic switches for battery pack charging and discharging control, including but not limited to the following: MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors), relays, IGBTs (Insulated Gate Bipolar Transistors), transistors (such as bipolar transistors), and contactors. MOSFETs can be N-channel or P-channel; relays are components that control mechanical switches using electromagnets and are suitable for applications requiring high isolation; IGBTs combine the advantages of MOSFETs and bipolar transistors and are suitable for high-power, high-voltage battery management systems; contactors are switches that close or open contacts using electromagnetic action and are suitable for high-current applications requiring physical isolation.

[0043] In this embodiment, all or part of the charging control electronic switch and the discharging control electronic switch can be selected from MOSFETs. Compared with other electronic components, MOSFETs have the following advantages as charging and discharging control switches: low on-resistance, which can reduce energy loss, improve system efficiency, and reduce heat generation; fast switching, which helps to achieve precise charging and discharging control; cost-effectiveness, as the production cost of MOSFETs is relatively low, and their high efficiency and small size can reduce the additional cooling requirements and space occupation of the system, thereby reducing the overall cost; design flexibility, as MOSFETs are available in various types and specifications to adapt to different voltage, current, and operating temperature requirements, providing a wide range of choices and facilitating system design and optimization; easy integration, as MOSFETs are small in size and easy to integrate with microcontrollers, integrated circuits, and other electronic components; good temperature stability, as MOSFETs have stable performance within a certain temperature range, which can improve the stability of the system; and low quiescent current, as the quiescent current of MOSFETs in the non-conducting state is very low, which helps to reduce the energy loss of the battery in standby or storage states.

[0044] In related technologies, because battery packs have consistent charging specifications and the charging current is much smaller than the discharging current, the charging and discharging circuits are identical. Therefore, the charging control electronic switch needs to be designed in the same way as the discharging control electronic switch, leading to a significant increase in battery pack costs. Furthermore, using the same charging and discharging port also increases costs.

[0045] Taking MOSFETs as an example, if the charging and discharging circuits are the same, the charging MOSFET must be designed according to the same specifications as the discharging MOSFET. However, using high-specification MOSFETs for discharging increases the overall cost of the BMS, and these costs may not be necessary for tools with different power requirements.

[0046] In this embodiment, by separating the charging and discharging circuits, the specifications of the charging control electronic switches and the discharging control electronic switches can be selected separately according to the different charging and discharging requirements, reducing the cost increase caused by using the same charging and discharging port. For example, charging typically requires a lower current, while discharging may require a higher current carrying capacity. This allows for optimization of component selection for each circuit, thereby reducing costs. Furthermore, the separately designed charging circuit can focus on optimizing for lower currents, helping to improve the efficiency of the entire system during charging and reducing losses and heat generation; simultaneously, the discharging circuit can focus on high current requirements, improving performance during discharging. In addition, separate current circuits make it easier to isolate faults, preventing a problem in one circuit from affecting another, thus improving the safety of the entire system.

[0047] According to the embodiments provided in this application, a battery pack is installed on a garden tool. The battery management system applied to the battery pack includes: a charging line, a discharging line, a charging interface, and a discharging interface. The charging line includes a charging control electronic switch for controlling the charging of the battery pack. The discharging line includes a discharging control electronic switch for controlling the discharging of the battery pack. The specifications of the discharging control electronic switch are different from those of the charging control electronic switch, and the discharging control electronic switch and the charging control electronic switch do not share a current loop. The charging interface and the discharging interface are different interfaces. This solves the problem of low charging efficiency caused by unnecessary power loss during the charging process in related battery management systems, thus improving the charging efficiency of the battery pack.

[0048] In one exemplary embodiment, a MOSFET is used as the charging control electronic switch to provide low on-resistance, fast switching response and high efficiency. Correspondingly, both the charging control electronic switch 1011 and the discharging control electronic switch 1021 can be MOSFETs.

[0049] Optionally, in this embodiment, the stable operation of the entire system can be controlled by a system control module, which may include, but is not limited to, charge / discharge control, communication, and data processing. Figure 2 As shown, the battery management system also includes a system control module 201, which controls the charging control electronic switch 1011 and the discharging control electronic switch 1021.

[0050] The system control module 201 can be connected to the charging control electronic switch 1011 and the discharging control electronic switch 1021 in the following manner: the system control module 201 is connected to the gate of the charging control electronic switch 1011 and the gate of the discharging control electronic switch 1021; the source of the charging control electronic switch is connected to the charging interface and its drain is connected to the positive terminal of the battery pack; the source of the discharging control electronic switch is connected to the discharging interface and its drain is connected to the positive terminal of the battery pack. Using this connection method, the system control module 201 can more conveniently control the charging control electronic switch 1011 and the discharging control electronic switch 1021.

[0051] In this embodiment, using a MOSFET as the charging control electronic switch provides low on-resistance, fast switching response, and high efficiency. The system control module controls the charging and discharging process, enhancing control over the battery pack's charging and discharging process and improving its safety.

[0052] In one exemplary embodiment, to reduce the number of high-specification components (which are typically more expensive) on the charging circuit while achieving finer control over the charging circuit, a series configuration of multiple charging control electronic switches can be used to control the charging of the battery pack. For example, as Figure 3As shown, there are two charging control electronic switches 1011. The source of the first charging control electronic switch 1011 is connected to the charging interface 103, the drain is connected to the source of the second charging control electronic switch 1011, and the gate is connected to the system control module 201. The drain of the second charging control electronic switch 1011 is connected to the positive terminal of the battery pack, and the gate is connected to the system control module 201.

[0053] For the aforementioned dual charging control electronic switches, the first charging control electronic switch can be responsible for the current control between the external charging interface and the second charging control electronic switch, ensuring a smooth introduction of charging current; while the second charging control electronic switch can be directly connected to the positive terminal of the battery pack to accurately manage the charging state of the battery.

[0054] This embodiment employs a dual-charge control electronic switch design, which reduces the need for high-specification components (which are typically more expensive) on the charging circuit, lowering component costs. It also enables precise control of the charging circuit. The independent gate control mechanism of the dual switches allows the system control module to flexibly adjust the charging strategy, adapt to different charging conditions, optimize charging efficiency, and extend battery life.

[0055] In one exemplary embodiment, to improve the matching degree between the battery pack output voltage and the system control module's supply voltage, a step-down circuit can be provided between the positive terminal of the battery pack and the system control module to reduce the battery pack voltage to the system control module's supply voltage. For example... Figure 4 As shown, the battery management system also includes a step-down circuit 401, which is disposed between the positive terminal of the battery pack and the system control module 201, for reducing the voltage of the battery pack to the power supply voltage of the system control module 201.

[0056] Here, a step-down circuit is set between the positive terminal of the battery pack and the system control module to improve voltage matching and system compatibility: if the positive terminal of the battery pack is directly connected to the system control module, it may damage the system control module. By setting a step-down circuit, the high voltage of the battery pack can be converted into a voltage suitable for the operation of the system control module, thereby ensuring that the system control module can operate stably without damage.

[0057] Buck converters can employ a switching mode, which offers high conversion efficiency and minimal energy loss. Especially for energy-limited devices like battery packs, improved energy conversion efficiency means more efficient use of battery energy and reduced energy loss during voltage conversion. Therefore, buck converters can maximize battery energy utilization, extend battery life and overall system uptime, while reducing heat generation issues caused by low energy conversion efficiency.

[0058] Furthermore, the buck converter reduces energy loss, thereby reducing heat generation. In addition, the buck converter can include overvoltage and overcurrent protection mechanisms, enabling it to quickly respond and cut off power when abnormal conditions are detected, preventing heat buildup and excessive battery discharge, and protecting the system control module from damage.

[0059] In this embodiment, a step-down circuit is set between the positive terminal of the battery pack and the system control module to reduce the voltage of the battery pack to the supply voltage of the system control module. This improves the voltage matching between the battery pack and the system control module, increases the efficiency of energy conversion, and enhances the thermal management and safety of the system, thereby ensuring the stable and efficient operation of the battery management system.

[0060] In one exemplary embodiment, such as Figure 5 As shown, the battery management system further includes: a first communication module 501 and a status detection module 502; wherein, the first communication module 501 is electrically connected to the data bus and is used as a slave to receive data sent by the master; the status detection module 502 is connected to the system control module 201 and is used to detect the status of the battery pack and transmit the detected battery pack status data to the system control module 201; the system control module 201 is also used to send the battery pack status data to the data bus through the first communication module 501.

[0061] In this embodiment, the state of the battery pack can be detected by a state detection module 502 located inside the battery pack. The state detection module 502 can detect the real-time state of the battery cells (e.g., cell voltage) to ensure that the cells operate within a safe range. In this case, the state detection module 502 can also be called a cell state monitoring module. The state detection module 502 can transmit the detected battery pack state data to the system control module 201. In the case of detecting cell voltage, the battery pack state data can include the battery pack voltage data.

[0062] The system control module 201 can process the received battery pack status data. For example, it can parse the battery pack status data, analyze the battery pack status by combining the battery pack status data over a period of time, and promptly issue a reminder when an abnormality is detected in the battery pack, or perform other processing operations.

[0063] Considering the limited processing power of the battery pack itself, and based on other considerations such as data storage, a first communication module 501 can be set up. The first communication module 501 is electrically connected to the data bus and can be used as a slave to receive data sent by the master. For battery pack status data, the system control module 201 can send the battery pack status data to the data bus through the first communication module 501, so that the master can understand the operating status of the battery pack in real time, including battery pack voltage data.

[0064] Optionally, the system control module is also used to parse the received battery pack status data. If the battery pack voltage is too high (exceeding the first voltage threshold), the charging protection mechanism is triggered to cut off the charging circuit. If the battery pack voltage is too low (below the second voltage threshold), the discharge protection is activated to prevent over-discharge.

[0065] Here, the integration of the status detection module and the system control module ensures real-time monitoring of the battery pack status. Once an anomaly is detected, such as the battery pack voltage exceeding the safe range, the system control module can react quickly and implement protective measures to prevent battery damage and ensure system safety. The connection between the first communication module and the data bus enables the host to acquire battery pack status data in real time. This strengthens information sharing between systems, allows the host to adjust the charging and discharging strategy according to the real-time status of the battery pack, improves the overall system intelligence level, and enhances the adaptability of the battery pack and the collaborative working capability of the equipment.

[0066] This embodiment enhances the safety and intelligence of the battery management system through real-time monitoring and intelligent data communication. This design optimizes battery usage, reduces maintenance costs, and improves equipment performance and lifespan.

[0067] In one exemplary embodiment, such as Figure 6 As shown, the battery management system also includes a temperature detection circuit 601, which is connected to the status detection module 502, for detecting the battery pack temperature and uploading the detected battery pack temperature data to the status detection module 502.

[0068] In this embodiment, the battery pack status detected by the status detection module 502 also includes the battery pack temperature. Correspondingly, the battery pack status data also includes battery pack temperature data. To detect the battery pack temperature, a temperature detection circuit 601 can also be set up to detect the battery pack temperature and upload the detected battery pack temperature data to the status detection module 502.

[0069] The temperature detection circuit 601 may include multiple temperature sensors and signal processing circuitry. The temperature sensors are in direct contact with or very close to the battery cells inside the battery pack, enabling real-time measurement of the battery pack temperature. The signal processing circuitry is responsible for converting the analog signals output by the temperature sensors into digital signals, so that the battery pack temperature data can be uploaded to the status detection module 502.

[0070] To ensure accurate monitoring of the entire battery pack's temperature, in this embodiment, temperature sensors are evenly distributed within the battery pack, covering all critical heat-generating areas, including between battery cells, at the contact points between the cells and the battery casing, and other heat-sensitive parts of the battery pack. This arrangement provides more comprehensive and accurate temperature data, helping the system to more accurately determine the battery pack's thermal state. The signal processing circuit converts the analog signals collected by the temperature sensors into digital signals and uploads the data to the status detection module 502 via a serial communication interface or other interfaces. The status detection module 502 is responsible for collecting and processing various status information of the battery pack, including voltage and temperature data.

[0071] Here, the addition of temperature data allows for a more comprehensive assessment of the battery pack's current state. During charging or discharging, if the battery pack temperature is detected to exceed the preset safe range, the status detection module can send an alarm to the system control module. The system control module will then take appropriate measures based on the alarm type, such as reducing charging / discharging power, pausing charging / discharging operations, or activating the battery pack's cooling system to ensure that the battery pack operates within a safe temperature range.

[0072] Through this embodiment, by monitoring the battery pack temperature in real time, the charging and discharging strategy can be dynamically adjusted to avoid battery performance degradation and safety risks caused by excessively high or low temperatures. In addition, temperature data can also be used to predict the battery pack's lifespan and provide early warnings of potential thermal runaway risks, thereby improving the safety and reliability of the entire system.

[0073] In one exemplary embodiment, precise detection of the battery pack current can be achieved by integrating a current-sensing resistor, thereby enriching the data acquisition capabilities of the state monitoring module and providing more accurate current information for battery management. Based on this, the system can more effectively control the charging and discharging process, ensuring the safe operation of the battery pack and extending its service life. Figure 7 As shown, the battery management system also includes a current sensing resistor 701, which is connected to the state detection module 502 and the negative terminal of the battery pack. The state detection module 502 is also used to detect the current of the battery pack through the current sensing resistor 701 to obtain the battery pack current data.

[0074] The current sensing resistor 701 can be positioned between the negative terminal of the battery pack and the state detection module 502. Its placement must ensure accurate measurement of the charging and discharging current flowing through the battery pack. One end of the current sensing resistor 701 is directly connected to the negative terminal of the battery pack, while the other end is connected to the current detection input terminal of the state detection module 502. This connection allows the state detection module 502 to monitor changes in the battery pack current in real time through the current sensing resistor 701. The selection criteria for the current sensing resistor 701 can include ensuring a stable resistance value within the expected current range and effectively withstanding the maximum current of the battery system.

[0075] Optionally, the current detection method can be as follows: when the battery pack is charging and discharging, the current will flow through the current sensing resistor 701, generating a voltage drop; the status detection module 502 monitors the voltage change across the current sensing resistor 701 and calculates the actual current value flowing through the battery pack according to Ohm's law (voltage = current × resistance).

[0076] For the status detection module 502, it can read the voltage value across the current sensing resistor 701 in real time or periodically, convert the voltage value into current data, integrate it into the battery pack status data, and upload it to the system control module 201. The battery pack status data may also include battery pack current data.

[0077] Here, by monitoring the current in real time, the status detection module can help the system identify abnormal conditions such as overcurrent and short circuit, and send alarms to the system control module in a timely manner. The system control module can then adjust the charging / discharging control strategy according to the alarm information, such as reducing the charging and discharging power, in order to resolve the abnormal conditions.

[0078] In this embodiment, the current data of the battery pack is obtained through the current sensing resistor. The acquisition of current data helps the system to detect faults such as overcurrent and short circuit in a timely manner, improves the efficiency of fault diagnosis and handling, and ensures the safe operation of the battery pack.

[0079] In one exemplary embodiment, to achieve efficient data exchange between the battery management system and an external terminal device, a communication module for communicating with the terminal device can be provided. For example... Figure 8 As shown, the battery management system further includes a second communication module 801 and a third communication module 802; wherein, the second communication module 801 is electrically connected to the data bus and is used to passively receive bus data from the data bus and transmit the received bus data to the third communication module 802; the third communication module 802 is connected to the system control module 201 and is used to establish a connection with the terminal device, obtain the data requested by the terminal device through the data bus, and transmit the data requested by the terminal device to the terminal device.

[0080] The second communication module 801 can be designed as a passive receiver, electrically connected to the data bus. Its main responsibility is to receive data streams from the data bus and forward these data to the third communication module 802. Here, the complexity of data processing and wireless transmission is transferred from the system control module to a dedicated communication module, reducing the burden on the system control module and improving the overall system response speed and data processing efficiency.

[0081] The third communication module 802 is a key component directly connected to the system control module 201, responsible for establishing communication connections with external terminal devices. Depending on the actual application environment and user requirements, the third communication module 802 can be a wired communication module or a wireless module (wireless communication module). Wired communication modules are suitable for applications requiring stable, high-speed data transmission, while wireless modules are more suitable for applications requiring wireless connectivity and low power consumption. Optionally, the third communication module 802 can be a BLE (Bluetooth Low Energy) module, a WIFI (Wireless Fidelity) module, or other wireless modules.

[0082] Taking battery pack status data as an example, the system control module can perform preliminary processing and analysis on the collected battery pack status data. The processed battery status data is then transmitted to the second communication module via the data bus. The second communication module passively receives this data, and the received data is forwarded to the third communication module, which then transmits the received data to the terminal device.

[0083] In this embodiment, the introduction of a second communication module as a data transmission relay can effectively reduce the data processing pressure on the system control module and improve the efficiency and reliability of data transmission. Separating the functions of data transmission and wireless communication from the system control module and having them handled by a dedicated communication module helps optimize the allocation of resources within the system, allowing the system control module to focus on core battery management tasks and improve the overall performance of the system.

[0084] In one exemplary embodiment, adding a prompting component can provide intuitive and immediate feedback on the battery pack status, enhancing the system's interactivity and safety. Correspondingly, such as... Figure 9 As shown, the battery management system also includes a prompting component 901, which is connected to the system control module 201 and is used to prompt the status of the battery pack under the control of the system control module 201.

[0085] The alerting component 901 can be an LED (Light Emitting Diode) indicator, a buzzer, a vibration motor, a display screen, or any component suitable for immediate alerting. Taking LED indicators and buzzers as examples, the LED indicator can display different colors or flashing patterns to indicate different states of the battery pack; for example, green indicates normal operation, red indicates a warning, and orange indicates a maintenance or inspection requirement. Flashing patterns can be used to indicate specific fault codes or remaining battery percentage. The buzzer can sound an alarm when an emergency condition (such as overheating, overcharging, short circuit, etc.) is detected, alerting nearby personnel to take immediate action to avoid potential safety accidents.

[0086] The prompting component 901 is connected to the system control module 201 via a set of control lines. The system control module 201 monitors the battery pack's status data. When it detects a situation requiring prompting (e.g., status data exceeding a preset normal range), it sends a control signal to the prompting component 901 to trigger a corresponding prompt action. To make the prompts easier to understand and respond to, the system control module 201 can also work with the display screen to show more detailed text prompts or icons, such as "Temperature too high, please pause charging" or "Battery level below 10%, immediate charging recommended," providing users with more operational guidance.

[0087] By integrating a prompting component into the battery management system, the interactivity and safety of the system can be enhanced. This allows users to understand the status of the battery pack through intuitive prompts, take timely and correct actions, and ensure the stable operation of the battery system.

[0088] In one exemplary embodiment, to reduce system cost and power consumption, different specifications of electronic switches can be selected according to different charging and discharging requirements. Separating the charging and discharging circuits allows for different specifications for the discharging control electronic switch and the charging control electronic switch, providing convenience. Considering the limitation of charging current, the specifications of the charging control electronic switch can be higher than those of the charging control electronic switch. Taking MOSFETs as an example, different specifications of charging and discharging control MOSFETs do not share a current loop. The charging interface is a separate interface that plugs into the charger for charging, while the discharging interface can plug into the tool's interface.

[0089] In this embodiment, both the charging control electronic switch and the discharging control electronic switch can be MOSFETs. To enhance system safety, a fuse can be added between the source of the discharging control electronic switch and the discharging interface. A fuse is a protective element that protects a circuit by melting under overcurrent conditions. In a battery management system, the current in the discharging circuit is usually large. The fuse prevents current surges caused by abnormal conditions such as short circuits and overloads, thus protecting the electronic switch from damage due to excessive current. In addition, the melting of the fuse can also disconnect the battery pack from the external load, avoiding potential fire or explosion risks.

[0090] The rated current of the fuse can be slightly higher than the normal operating current of the discharge control electronic switch, but lower than its maximum permissible current, to ensure rapid melting and effective circuit protection in abnormal conditions. The fuse can be fixed on the printed circuit board via a fuse holder for easy replacement and maintenance.

[0091] In this embodiment, by employing high-specification discharge control electronic switches and low-specification charging control electronic switches, the battery management system can effectively reduce power loss during discharge, improve energy conversion efficiency, and extend the battery pack's lifespan. The addition of a fuse provides an extra layer of safety protection for the battery management system, enabling it to quickly respond to abnormal current, prevent cell overheating, short circuits, and other safety issues, and enhance the system's safety under high-power discharge conditions.

[0092] The battery management system in this application embodiment will be explained below with reference to optional examples. In this optional example, the first communication module is communication module 1, the second communication module is communication module 2, the third communication module is a BLE module, the status detection module is a cell status monitoring module, the charging control electronic switch and the discharging control electronic switch are both MOSFETs, and the indication component is an LED indicator.

[0093] An example of a BMS charging / discharging port is as follows: Figure 10 As shown, the charging and discharging control MOS transistors are of the same specification and share a common current loop. The P+ / C+ interface is the common terminal for the charging and discharging interface. An example of a BMS with different charging and discharging ports is shown below. Figure 11 As shown, the charging and discharging control MOS has different specifications and does not share a current loop. The charging port C+ is a separate interface that is plugged into the charger for charging, while the P+ interface is plugged into the tool end interface and serves as the discharging interface.

[0094] exist Figure 10 and Figure 11In the system, the cell status monitoring module monitors the real-time status of the cells, including cell temperature, voltage, and current parameters. The temperature detection circuit detects cell temperature data and uploads it to the cell status monitoring module. Communication module 1 is connected to the BUS bus as a slave device to receive data from the master device. The system control module sends battery pack status data through communication module 1. Communication module 2 is connected to the BUS bus and passively receives bus data, transmitting it to the BLE module. The BLE module is used for human-machine interaction of end-user devices, allowing users to view corresponding device operating data and historical usage information.

[0095] By separating the charging and discharging circuits and selecting the appropriate MOSFET specifications for each circuit according to the different charging and discharging requirements, the component selection for each circuit can be optimized, thereby reducing costs and power losses, thus improving overall efficiency.

[0096] It should be noted that the above modules can be implemented by software or hardware. For the latter, they can be implemented in the following ways, but are not limited to: all the above modules are located in the same processor; or, the above modules are located in different processors in any combination.

[0097] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the principles of this application should be included within the protection scope of this application.

Claims

1. A battery management system, characterized in that, The battery management system, applied to a battery pack mounted on garden tools, includes: charging lines, discharging lines, a charging interface, a discharging interface, and a system control module. The charging interface and the discharging interface are different interfaces. The charging circuit includes a charging control electronic switch for controlling the charging of the battery pack. The discharge circuit includes a discharge control electronic switch for discharging the battery pack. The specifications of the discharge control electronic switch are different from those of the charging control electronic switch, and the discharge control electronic switch and the charging control electronic switch do not share a current loop. The system control module is used to control the charging control electronic switch and the discharging control electronic switch; In this configuration, both the charging control electronic switch and the discharging control electronic switch are MOSFETs. The system control module is connected to the gate of the charging control electronic switch and the gate of the discharging control electronic switch. The source of the charging control electronic switch is connected to the charging interface and the drain is connected to the positive terminal of the battery pack. The source of the discharging control electronic switch is connected to the discharging interface and the drain is connected to the positive terminal of the battery pack.

2. The battery management system according to claim 1, characterized in that, The number of charging control electronic switches is two. The source of the first charging control electronic switch is connected to the charging interface, the drain is connected to the source of the second charging control electronic switch, and the gate is connected to the system control module. The drain of the second charging control electronic switch is connected to the positive terminal of the battery pack, and the gate is connected to the system control module.

3. The battery management system according to claim 1, characterized in that, The battery management system also includes: A step-down circuit is disposed between the positive terminal of the battery pack and the system control module to reduce the voltage of the battery pack to the power supply voltage of the system control module.

4. The battery management system according to claim 1, characterized in that, The battery management system further includes: a first communication module and a status detection module; wherein... The first communication module is electrically connected to the data bus and is used as a slave to receive data sent by the master. The status detection module is connected to the system control module and is used to detect the status of the battery pack and transmit the detected battery pack status data to the system control module. The battery pack status data includes the battery pack voltage data. The system control module is also used to send the battery pack status data to the data bus through the first communication module.

5. The battery management system according to claim 4, characterized in that, The battery management system also includes: A temperature detection circuit, connected to the status detection module, is used to detect the battery pack temperature and upload the detected battery pack temperature data to the status detection module. The battery pack status data also includes the battery pack temperature data.

6. The battery management system according to claim 4, characterized in that, The battery management system further includes: a current-sensing resistor, which is connected to the state detection module and the negative terminal of the battery pack; wherein, The status detection module is further configured to detect the current of the battery pack through the current sensing resistor to obtain battery pack current data, wherein the battery pack status data also includes battery pack current data.

7. The battery management system according to claim 1, characterized in that, The battery management system further includes: a second communication module and a third communication module; wherein... The second communication module is electrically connected to the data bus and is used to passively receive bus data from the data bus and transmit the received bus data to the third communication module. The third communication module is connected to the system control module and is used to establish a connection with the terminal device, obtain the data requested by the terminal device through the data bus, and transmit the data requested by the terminal device to the terminal device. The third communication module is a wireless module.

8. The battery management system according to claim 1, characterized in that, The battery management system also includes: The indicator component, connected to the system control module, is used to indicate the status of the battery pack under the control of the system control module.

9. The battery management system according to any one of claims 1 to 8, characterized in that, The specifications of the discharge control electronic switch are higher than those of the charging control electronic switch, and a fuse is provided between the source of the discharge control electronic switch and the discharge interface.

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