Integrated topological architecture of sodium ion battery charge and discharge protection system

Abstract

The invention discloses an integrated topological architecture of a sodium ion battery charging and discharging protection system, which is characterized in that a system control center, a battery state simulation sampling front-end circuit, a combined section switch K1, a multi-path DCDC bidirectional buck-boost module, a pump battery module, a detection component A0, a detection component V0 and a polar capacitor C1 cooperatively work; and effective management and protection of charging and discharging of the sodium-ion battery are realized. According to the invention, the topological design is innovative, the charging and discharging process can be accurately controlled, and meanwhile, the high-rate charging and discharging characteristics of the sodium ion battery can be completely maintained, namely, rapid charging and discharging can be conveniently realized, and even in a special application place, a control center design of energy recovery and AI element energization can be realized under the condition of not adding other hardware; and battery application scene function expansion spaces are reserved from hardware to software, so that the use characteristics of the sodium-ion battery are enriched, and the application safety range of the sodium-ion battery is widened.

Description

Technical Field

[0001] The present invention relates to a lithium battery management system, and more particularly to an integrated topology architecture of a charge and discharge protection system for a sodium ion battery. Background Art

[0002] Secondary batteries, especially products based on the technical route represented by lithium ion batteries, have developed vigorously and become a representative industry of new energy success. Their application scope almost covers all industries from civilian to industrial. The most representative is new energy vehicles, and others such as new energy energy storage, household appliances (such as floor sweeping robots), etc. In order to use such batteries safely and reliably, a battery protection system (abbreviation: BMS) has been developed. This system mainly ensures that the battery is used within a safe range (parameters such as the use environment temperature, battery voltage, charge and discharge current, etc.). When the battery is in use, if any parameter exceeds the use range, the system will limit or terminate the use of the battery to avoid safety hazards during the use of the battery. Therefore, such a system only responsible for the safe use of the battery and does not responsible for charge and discharge management.

[0003] As Figure 1 shown Figure 1 is a traditional lithium battery BMS management architecture. A switch SW1 is provided in the positive electrode circuit of the battery, and a switch SW2 is provided in the negative electrode circuit. The system control center controls the switch SW1 and the switch SW2 respectively, and it is also connected to an auxiliary battery system and a front end for analog sampling of battery status. The front end for analog sampling of battery status is connected in parallel with the battery.

[0004] 1. SW1 is a high-side on-off control; SW2 is a low-side on-off control, usually one of the two.

[0005] 2. The switch control includes electromagnetic control and electronic switches composed of power electronic devices. Electromagnetic control such as relay switch control, and electronic switches include MOS transistors, GAN transistors, IGBTs, SIC transistors for controlling switches, and these are all determined according to the use scenario.

[0006] 3. The system control center is basically a general-purpose MCU. Its main work is to complete the state control logic, determine whether the battery is working under the set state, and immediately shut down if it exceeds the standard (by controlling SW1 or SW2), and at the same time complete transactional work such as battery power measurement and external communication.

[0007] The above architecture is designed for lithium-ion batteries (regardless of ternary or lithium iron phosphate batteries), and its protection and control of lithium-ion batteries are quite effective. Since the voltage output range of lithium-based ion batteries is relatively narrow, usually 3.0 - 4.2V for ternary battery cells and 2.5 - 3.65V for lithium iron phosphate batteries, that is, within a fluctuation range of about 40%, it can adapt to most usage loads. Therefore, only safety management of the battery is required, and charge and discharge management is not necessary. The battery pack can well adapt to the usage load. However, the voltage range of sodium-ion batteries varies between 1.5 - 4.0, with a variation amplitude of over 260%, and no electrical load can adapt to such a wide voltage change range. Therefore, directly applying the BMS scheme of lithium-ion batteries cannot solve the normal use of sodium-ion batteries.

[0008] In view of this, it is necessary to improve the traditional lithium battery BMS management architecture. Summary of the Invention

[0009] Aiming at the deficiencies in the prior art, the technical problem to be solved by the present invention is to provide an integrated topology architecture for a charge and discharge protection system of sodium-ion batteries. The purpose of designing this topology architecture is to solve the problem that sodium-ion batteries cannot be fully discharged normally due to a large voltage change range, while retaining their high-rate charging and discharging characteristics, and significantly improving the user experience when the battery is at low voltage.

[0010] To solve the above technical problems, the present invention is achieved through the following solutions: An integrated topology architecture for a charge and discharge protection system of sodium-ion batteries of the present invention includes a system control center and a front-end circuit for analog sampling of battery states. The front-end circuit for analog sampling of battery states is connected in parallel to the battery for sampling the battery, and it is connected to the system control center through a system control bus. The negative terminal of the front-end circuit for analog sampling of battery states is grounded. The topology architecture further includes: A combined segmented switch K1 provided on the main circuit of the battery. The combined segmented switch K1 has a switching circuit, and it is connected to the switch control pin of the system control center through a combined segmented switch status control line; Multiple DCDC bidirectional buck-boost modules connected to the system control center through the system control bus and connected in parallel. The positive poles of the first battery input ends of each DCDC bidirectional buck-boost module are all connected to the output end of the combined segmented switch K1 after being connected in series with their respective detection units DCLH, and the negative poles of the first battery input ends of each DCDC bidirectional buck-boost module are all connected to the negative pole of the battery output after being connected in series with their respective detection units DCLL. The positive poles of the second battery input ends of each DCDC bidirectional buck-boost module are connected in parallel to the BAT+ / A1 point, and then connected to the positive pole of the battery through a series-connected current detection component A1; A pump battery module connected to the system control center. The first end of the pump battery module is connected to the output end of the combined sectional switch K1 after being connected in series with its respective detection unit DCLH. Its second end is connected to the positive battery output and the first end of the auxiliary battery system after being connected in series with its respective detection unit DCLL. The second end of the auxiliary battery system is connected to the system control center and the auxiliary battery output ends of each DCDC bidirectional buck-boost module. Detection component A0, which is arranged on the battery output positive circuit node and is monitored in real time by the system control center. This detection component AO is a parameter for completing AI-like control, and its real-time data and converted data are used for the overall system state control. Detection component V0, which is arranged between the battery output positive circuit and the negative circuit. This detection component V0 is used for real-time voltage detection, and its real-time data and converted data are used for the overall system state control, and it is a parameter for completing AI-like control. There is a polarized capacitor C1. The positive pole of the polarized capacitor C1 is connected to the positive circuit of the battery output. The polarized capacitor C1 is also connected in parallel with multiple DCDC bidirectional buck-boost modules, and its negative pole is connected to the negative circuit of the battery output.

[0011] Further, the combined sectional switch K1 includes a diode D1, a switch SW1, and a switch SW2. The diode D1 and the switch SW1 are connected in parallel, and the diode D1 is connected in series with the switch SW2. The positive pole of the diode D1 is connected to the BAT+ / A1 point and then connected in series with the current detection unit A1 to access the battery positive pole, and its negative pole is connected to the first end of the switch SW2. The state control line of the combined sectional switch is connected to the corresponding control pin of the system control center to control the on / off, and its energy is provided by the dedicated pump battery.

[0012] Further, the switch SW1 and the switch SW2 form a combined switch. The switch SW1 includes one of a first mechanical switch, a first solid-state electronic switch device, and a first liquid electronic switch. The switch SW2 includes one of a second mechanical switch, a second solid-state electronic switch device, and a second liquid electronic switch.

[0013] Furthermore, when the switch SW1 is the first mechanical switch, the first mechanical switch is the first relay. When the switch SW1 is the first solid-state electronic switch device, the first solid-state electronic switch device includes one of a MOS tube, a GAN power device, and a SIC power device. When the switch SW2 is the second mechanical switch, the second mechanical switch is the second relay. When the switch SW2 is the second solid-state electronic switch device, the second solid-state electronic switch device includes one of a MOS tube, a GAN power device, and a SIC power device.

[0014] Further, the DCDC bidirectional buck-boost module includes a DCDC bidirectional buck-boost circuit, and the DCDC bidirectional buck-boost circuit includes: A first driving module, the driving signal terminal of which is connected to the system control center; MOS transistor Q1 and MOS transistor Q2, the gates of the MOS transistor Q1 and the MOS transistor Q2 are both connected to the first driving module, the source of the MOS transistor Q1 is connected to the drain of the MOS transistor Q2, after the source of the MOS transistor Q2 is connected in series with the DCLL current detection unit, it is connected to the negative electrode of the battery, and after the drain of the MOS transistor Q1 is connected in series with the DCLH current detection unit, it is connected to OUT+ / A, and is connected to the positive electrode of the battery pack output port after passing through the detection unit A0; Inductor L1, the first end of the inductor L1 is connected to the circuit node between the drain of the MOS transistor Q1 and the source of the MOS transistor Q2, and its second end is connected to the battery BAT+ / A1 pin.

[0015] Further, the pump battery module includes: A pump battery control unit, which has an independent pump battery parameter control module, and the pump battery control unit is also connected to the system control center and is controlled in real time by the system control center; A second driving module, one end of the second control module is connected to the first control end of the pump battery control unit, and its control parameters come from the pump battery control unit; MOS transistor Q3 and MOS transistor Q4, the gates of the MOS transistor Q3 and the MOS transistor Q4 are both connected to the second driving module, wherein the source of the MOS transistor Q4 is grounded, and its drain is connected to the source of the MOS transistor Q3; Inductor L2, the first end of the inductor L2 is connected to the circuit node between the drain of the MOS transistor Q4 and the source of the MOS transistor Q3, and the second end of the inductor L2 is connected to the battery OUT+ / A point; A polarized capacitor C3, the negative electrode of the polarized capacitor C3 is connected to the grounding pin of the MOS transistor Q4, and its positive electrode is connected to the drain of the MOS transistor Q3 and is connected to the BSOUTV+ pin of the battery; A polarized capacitor C2, the negative electrode of the polarized capacitor C2 is connected to the second end of the inductor L2, and its positive electrode is connected to the drain of the MOS transistor Q3; A series of resistor R1 and resistor R2, the first end after the resistor R1 and the resistor R2 are connected in series is connected to the drain of the MOS transistor Q3, and the second end after the resistor R1 and the resistor R2 are connected in series is connected to the second end of the inductor L2; Resistor R3, the first end of the resistor R3 is connected to the drain of the MOS transistor Q3; A voltage regulator diode U1, the reference pin of the voltage regulator diode U1 is connected to the circuit node between the resistor R1 and the resistor R2, its second pin is connected to the second end of the inductor L2, and its third pin is connected to the second end of the resistor R3; A series of resistors R4 and R5, the first end after the resistors R4 and R5 are connected in series is connected to the drain of the MOS transistor Q3, and the second end after the resistors R4 and R5 are connected in series is connected to the circuit node between the voltage regulator diode U1 and the resistor R3; An optocoupler device U2, the positive electrode of the light-emitting end of the optocoupler device U2 is connected to the circuit node between the resistors R4 and R5, the negative electrode of its light-emitting end is connected to the second end after the resistors R4 and R5 are connected in series, the collector of its light-receiving end is connected to the second control end of the pump battery control unit, and the emitter of its light-receiving end is connected to the third control end of the pump battery control unit.

[0016] Furthermore, the system control center includes one of an MCU real-time control device and a DSP real-time control device.

[0017] Compared with the prior art, the beneficial effects of the present invention are: 1. The integrated charge and discharge management topology architecture of the sodium-ion battery of the present invention successfully solves the problem that the sodium-ion battery cannot be fully discharged normally due to a large voltage change range, while retaining its high-rate charging and discharging characteristics, significantly improving the user experience when the battery is at low voltage. In the backup power scenario, the backup power usage time is greatly extended, ensuring power safety. 2. The integrated topology architecture of the present invention can accurately control the operation of the system. The present invention uses a high-end MCU or DSP controller to construct a system control center, which can accurately identify and switch states such as system sleep, standby, charging, discharging, and energy recovery, realizing super real-time control. The hardware of the control system and the adapted software work together to ensure the stable and efficient operation of the system. 3. The integrated topology architecture of the present invention is closely combined with the innovatively designed segmented control switch K1 and the improved bidirectional DCDC module (group), and is equipped with a pump battery to optimize the system function, reduce heat consumption, and improve the power utilization efficiency.

[0018] 4. The integrated topology architecture of the present invention connects an output capacitor C1, a detection component A0, and a detection component V0 in the circuit, providing a solid hardware guarantee for the high dynamic performance of the system, enabling the system to quickly respond to load changes and meet the requirements of different usage scenarios.

[0019] 5. The integrated topology architecture of the present invention enables flexible charging management. The charging process of the integrated topology architecture of the present invention can be subdivided into multiple characteristic controls such as trickle charging, constant current charging, floating charging, and supercharging above 2C. For different charging batteries and battery states, the charging mode can be flexibly adjusted to protect the battery service life and ensure that the battery is fully charged, which is an advantage not possessed by traditional battery management systems.

[0020] 6. The integrated topology architecture of the present invention enables efficient discharge management and energy recovery. In terms of discharge management, the integrated topology architecture of the present invention can automatically switch the discharge mode according to the battery voltage to ensure a stable output of the rated voltage when the battery is at a low voltage, meeting the power consumption requirements of high-dynamic loads. In places where the motor is driven, energy recovery can be achieved, improving the system energy utilization rate and optimizing the user's power consumption experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is the management architecture diagram of the traditional lithium battery BMS.

[0022] Figure 2 This is the integrated topology architecture diagram of the sodium-ion battery charge and discharge protection system of the present invention.

[0023] Figure 3 This is the circuit diagram of the single-channel DCDC bidirectional buck-boost module of the present invention.

[0024] Figure 4 This is the circuit diagram of the pump battery module of the present invention.

[0025] Reference numeral in the drawings: Interface 1. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention. Obviously, the embodiments described herein are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0027] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0028] Embodiment 1: The specific structure of the present invention is as follows: Please refer to the attached Figures 2 - 4, the integrated topology architecture of a charge and discharge protection system for a sodium-ion battery according to the present invention includes a system control center and a front-end circuit for battery state analog sampling. The front-end circuit for battery state analog sampling is connected in parallel to the battery for sampling the battery, and is connected to the system control center through a system control bus. The negative terminal of the front-end circuit for battery state analog sampling is grounded. The system control center includes an MCU real-time control device or a DSP real-time control device.

[0029] The system control center is provided with a plurality of interfaces 1, and the plurality of interfaces 1 at least include a fast response interface capable of quickly connecting to peripherals and a communication interface for connecting a communication module.

[0030] The topology architecture further includes a combined sectional switch K1, a multi-channel DCDC bidirectional buck-boost module, a pump battery module, a detection component A0, a detection component V0, and a polarized capacitor C1.

[0031] The combined sectional switch K1 is arranged on the main battery path. The combined sectional switch K1 has a switching circuit, and is connected to the switch control pin of the system control center through a combined sectional switch status control line. The combined sectional switch K1 includes a diode D1, a switch SW1, and a switch SW2. The diode D1 and the switch SW1 are connected in parallel, and the diode D1 is connected in series with the switch SW2. The positive electrode of the diode D1 is connected to the positive electrode of the battery, and its negative electrode is connected to the first end of the switch SW2. The negative electrode of the diode D1 is connected to the switch control pin of the system control center through a combined sectional switch status control line.

[0032] The switch SW1 and the switch SW2 form a combined switch; The switch SW1 includes a mechanical switch or an electronic component switcher; The switch SW2 includes a mechanical switch or an electronic component switcher.

[0033] When the switch SW1 is a first mechanical switch, the first mechanical switch is a relay; When the switch SW1 is a first electronic component switcher, the first electronic component switcher includes a MOS transistor, a GAN power device, or a SIC power device; When the switch SW2 is a second mechanical switch, the second mechanical switch is a relay; When the switch SW2 is a second electronic component switcher, the second electronic component switcher includes a MOS transistor, a GAN power device, or a SIC power device.

[0034] Specifically, when the switch SW1 is a mechanical switch, a relay is a good choice due to its high reliability and strong current-carrying capacity. If it is an electronic component switch, MOS transistors (fast switching speed, small on-resistance), GAN power devices (high switching frequency, high efficiency), or SIC power devices (suitable for special environments such as high temperature) can be selected according to actual needs. The switch SW2 can also be selected from mechanical switches (such as relays) and electronic component switches (such as MOS transistors, GAN power devices, SIC power devices).

[0035] The multi-channel DCDC bidirectional buck-boost module is connected to the system control center through the system control bus and is connected in parallel. As Figure 3 shown, the positive poles of the first battery input ends of each DCDC bidirectional buck-boost module are all connected to the output end of the combined sectional switch K1, and the negative poles of their battery input ends are all connected to the grounding pin of the battery state simulation sampling front-end circuit. The positive poles of the second battery input ends of each DCDC bidirectional buck-boost module are also connected to the positive output of the battery; under the control of the system control center, the circuit of the DCDC bidirectional buck-boost module realizes bidirectional switching of energy output.

[0036] As Figure 4 shown, the pump battery module is connected to the system control center. The first end of the pump battery module is connected to the output end of the combined sectional switch K1, and its second end is respectively connected to the positive battery output and the first end of the auxiliary battery system. The second end of the auxiliary battery system is connected to the system control center and the auxiliary battery output ends of each DCDC bidirectional buck-boost module; The detection component A0 is arranged on the positive circuit node of each DCDC bidirectional buck-boost module and is monitored in real time by the current detection pin of the system control center; The detection component V0 is arranged between the positive circuit of each DCDC bidirectional buck-boost module and the negative circuit of each DCDC bidirectional buck-boost module, and the detection component V0 is monitored in real time by the voltage detection pin of the system control center; The positive pole of the polarized capacitor C1 is connected to the positive circuit of the multi-channel DCDC bidirectional buck-boost module, and its negative pole is connected to the negative circuit of the multi-channel DCDC bidirectional buck-boost module.

[0037] The DCDC bidirectional buck-boost module includes a DCDC bidirectional buck-boost circuit, and the DCDC bidirectional buck-boost circuit includes: A first drive module, the drive end is connected to the system control center; MOS transistors Q1 and Q2, the gates of MOS transistors Q1 and Q2 are both connected to the first driving module, the source of MOS transistor Q1 is connected to the drain of MOS transistor Q2, the source of MOS transistor Q2 is grounded and connected to the DCLL control pin of the system control center through the DCLL line, the drain of MOS transistor Q1 is connected to the DCLL control pin of the system control center through the DCLH line, and the drain of this MOS transistor Q1 is also connected to the battery OUT+ / A pin; Inductor L1, the first end of this inductor L1 is connected to the circuit node between the drain of MOS transistor Q1 and the source of MOS transistor Q2, and its second end is connected to the battery BAT+ / A1 point.

[0038] The pump battery module includes: A pump battery control unit, having three control terminals; A second driving module, one end of this second control module is connected to the first control terminal of the pump battery control unit; MOS transistors Q3 and Q4, the gates of MOS transistors Q3 and Q4 are both connected to the second control module. Among them, the source of MOS transistor Q4 is grounded, and its drain is connected to the source of MOS transistor Q3; Inductor L2, the first end of this inductor L2 is connected to the circuit node between the drain of MOS transistor Q4 and the source of MOS transistor Q3, and the second end of the inductor L2 is connected to the battery OUT+ / A pin; A polarized capacitor C3, the negative pole of this polarized capacitor C3 is connected to the grounding pin of MOS transistor Q4, and its positive pole is connected to the drain of MOS transistor Q3 and connected to the BSOUTV+ pin of the battery; A polarized capacitor C2, the negative pole of this polarized capacitor C2 is connected to the second end of inductor L2, and its positive pole is connected to the drain of MOS transistor Q3; Series-connected resistors R1 and R2, the first end after the series connection of resistors R1 and R2 is connected to the drain of MOS transistor Q3, and the second end after the series connection of resistors R1 and R2 is connected to the second end of inductor L2; Resistor R3, the first end of this resistor R3 is connected to the drain of MOS transistor Q3; Zener diode U1, the reference pin of this zener diode U1 is connected to the circuit node between resistors R1 and R2, its second pin is connected to the second end of inductor L2, and its third pin is connected to the second end of resistor R3; Series-connected resistors R4 and R5, the first end after the series connection of resistors R4 and R5 is connected to the drain of MOS transistor Q3, and the second end after the series connection of resistors R4 and R5 is connected to the circuit node between the zener diode U1 and resistor R3; Optocoupler device U2, the positive electrode of the light-emitting end of the optocoupler device U2 is connected to the circuit node between the resistor R4 and the resistor R5, the negative electrode of its light-emitting end is connected to the second end after the resistor R4 and the resistor R5 are connected in series, the collector of its light-receiving end is connected to the second control end of the pump battery control unit, and the emitter of its light-receiving end is connected to the third control end of the pump battery control unit.

[0039] Embodiment 2: Charging is subdivided into charging electrical characteristic control. Typical characteristics include trickle charge, constant current charge, floating charge. In special cases, there is also super charge above 2C. There is also the control of the DCDC module (group) during charging (mainly including but not limited to master-slave interleaved multi-way control, master-slave circuit synchronous control, multi-way parallel interleaved control, multi-way parallel synchronous control). Specific subdivision characteristics are determined according to specific products; the discharge characteristics are divided into directly discharging by the combined segmented switch K1 and discharging by switching the DCDC boost when the battery has a low voltage; during boost discharge, the load characteristic is feedforward following discharge, and the control strategy of the DCDC module (group) is controlled (mainly including but not limited to master-slave interleaved multi-way control, master-slave circuit synchronous control, multi-way parallel interleaved control, multi-way parallel synchronous control) In view of the characteristics of sodium-ion batteries and combining with the existing technology of the mature lithium-ion battery protection system, the present invention proposes Figure 2 a solution topology structure. Compared with the BMS system of conventional lithium-ion batteries, this topology adds a bidirectional DCDC module; a large-capacity output capacitor C1, a detection circuit for the output current (A0 in the figure) and output voltage (V0 in the figure) of the output port; a dedicated combined segmented switch K1 is configured on the high side, and a pump battery is specially built to cooperate with the high-end main switch. The general MCU of the conventional BMS is updated to a more advanced controller with strong real-time control capabilities such as but not limited to high-end MCU or DSP, and advanced control algorithms are used to realize the identification and control of the whole machine state. The working principle of the system is briefly introduced as follows: Figure 2 The core component modules of the system include: system control center, bidirectional buck-boost DCDC module, combined segmented switch K1 (SW1 and SW2 in the combined switch can be mechanical switches such as relay switches or electronic components such as power devices such as MOS tubes, GAN, and SIC), output large-capacity capacitor C1, pump battery, total output current detection unit A0, output voltage detection unit V0; other auxiliary function circuits include AFE analog front end, battery terminal input / output current detection unit A1, auxiliary circuit system, etc.; Figure 2 shown in Figure 2 the schematic diagram of a single-channel bidirectional DCDC, which realizes bidirectional switching of energy output under the control of the system control center; Figure 4 is the schematic diagram of the pump battery. The pump battery is used to reliably switch energy in different modes of the combined switch, and its working principle will be described later.

[0040] System working principle: The core part of the system of the present invention is the system control center. The system control center is not limited to dedicated real-time controller devices such as high-end MCUs and DSPs. Strong real-time data processing ability is its core requirement. It mainly completes: accurate identification and conversion of battery states - a total of five states including sleep, standby, charging, discharging, and energy recovery (there may be adjustments in different systems); data acquisition and calculation of charge and discharge power; communication management with the outside world; and high-speed real-time control in different states. According to the different states of the whole machine, its working process is subdivided into: Sleep: Conditions for entering the sleep state. Specifically, the present invention designs multiple sleep entry modes to adapt to different application scenarios. For example, external forced sleep, where the system is forced to enter the sleep state through an external instruction; communication instruction sleep, where the user can make the system sleep through a specific communication instruction; state sleep, which determines whether to sleep based on the switch state or high and low level states. When the system detects that the output / input current is lower than the set value, it will also automatically enter the sleep state. During sleep, the system power consumption is extremely low, which can be as low as dozens of microamps, minimizing the battery power consumption to the greatest extent.

[0041] Standby: In the standby mode, the system power consumption is slightly higher than that in the sleep state. At this time, SW2 of K1 in the charge and discharge circuit is closed, SW1 is disconnected, and the DCDC module (group) is in the off state. The system control center is also in a low-power state, but it can quickly respond to external state changes and quickly switch to the working state, and the energy consumption is maintained at the milliamp level.

[0042] Charge Management: This device has the same port for charging and discharging. When the discharge current is lower than the set value (in milliamperes, specifically determined according to the battery capacity, etc.) for about 30 seconds (adjustable according to the specific usage scenario, which can be as short as less than 1 second or as long as several hours), the system control center will disconnect SW1 of the sectional switch, and at the same time, the DCDC module (group) will also be in the off state. The system control center detects the changes in the voltage (V0) and current (A0) of the output port (the large output capacitor C1 can keep the output voltage unchanged for a long time when there is no load). If it detects that the output voltage V0 becomes lower and A0 increases, it will immediately switch to the discharge state. Conversely, if it detects that the V0 voltage rises, it will determine whether it is an energy recovery state or a charging state according to the pre-stored calculation method. When it is determined to be the charging state, it will enter the charging state. When entering the charging state, the system first detects the battery voltage and decides whether it is trickle charging, constant current charging, multiple charging rate (>1C), or floating charging according to the preset parameters and the inserted charging voltage. For example, taking the charging process of a battery pack with a rated voltage of 48V / 16 series / 20AH as an example, two charging routes are introduced to illustrate the charging control: a). When the user charges with a charger, that is, the maximum charging voltage is equal to the fully charged voltage of the battery, 59.2V. When the system control center detects that the V0 voltage rises and the voltage value is higher than the battery voltage, the control system determines that the battery pack is about to enter the charging mode. Then, according to the collected battery status information and the input charging parameter information (when there is no communication with the charging battery, it is judged only by the input voltage. The system reserves an interface for communication with the charging battery to coordinate the charging process control, specifically determined according to the usage scenario), when the total battery voltage is less than or equal to 24V, the system enters the trickle charging mode with the charging current controlled between 0.01 - 0.05C. When in the trickle charging mode, K1 is disconnected, and the DCDC turns on the corresponding DCDC module according to the power requirement. Usually, one path is sufficient. After the battery voltage is greater than 24V, the DCDC charging module is turned off, and it switches to K1 being turned on for direct charging. When the voltage is close to 57.6V, then K1 is turned off and it switches to the DCDC module (group) for step-down and power reduction (0.1C) charging. When the voltage is close to the fully charged voltage of 59.2V, the system switches to K1 being turned on for constant voltage charging until it is fully charged. b). When the user charges with an adapter, the charging voltage must be higher than the fully charged voltage, that is, 59.2V in this example, such as 60V. After the system detects the charging insertion, it directly disconnects K1, and the DCDC module completes the entire process of trickle charging (if any), constant current charging, power reduction, constant voltage floating charging. When the DCDC module (group) is responsible for charging, generally, the maximum power control has the ability to charge at 1C. At this time, the control center will adopt the master-slave control mode and adjust and distribute the working power of different modules as needed to ensure the optimal system efficiency and the least heat generation. The module charging control algorithm is completed by the system control center. On the right Figure 2 shown in Figure 2The schematic diagram works in the BUCK mode. At this time, the DCLH peak current detector is effective. The DCDC module will work in the per-cycle peak current mode for a single module under the control of the system control center. The DCDC module group works under the control of the system control center, adopting the master-slave pulse interleaved or synchronous control mode to avoid the circulating current between the modules. The master-slave mode can automatically distribute power between the modules according to the requirement of the total power, ensuring the optimal system efficiency and the lowest heat generation. From the above description, it can be seen that this architecture has flexible charging management, which can not only fully realize the high-rate charging of sodium batteries, but also very appropriately adjust the charging power throughout the process in accordance with the battery charging characteristics of the battery factory. The advantages of doing so are, firstly, to protect the battery service life, and secondly, to ensure that the battery is fully charged, which is not available in traditional battery management systems. At the same time, for motor loads, such as in the application scenarios of electric two-wheelers and three-wheelers, the charging management unit can immediately change to the energy recovery mode, that is, using the high charging rate characteristics of sodium-ion batteries, closing K1 and turning off the DCDC module, so that the battery pack can very timely and efficiently store the energy of braking, slopes, etc., improving the system energy utilization rate.

[0043] Discharge management: Except for the sleep and charging states, the entire battery management system is always switching between standby and discharge. The working details are as follows: Similar to the above charging example, for discharging, a battery pack with 48V / 20AH / 16 strings is taken as an example. Assume the system starts discharging from a fully charged state. At the initial stage of discharging, the system control center turns off the DCDC module (group) and turns on K1 to supply power to the load. When the battery voltage drops to only 40V, the system control center first turns off the switch SW1 in the segmented combination switch. Before the DCDC module (group) can establish the voltage normally, D1 and the switch SW2 provide freewheeling for the load. When the voltage of the DCDC module (group) reaches the rated voltage of 48V, D1 naturally turns off the current in the K1 channel due to its reverse characteristic. At this time, the system control center then turns off SW2. Since the current is zero, SW2 is turned off without loss. At this time, all the energy of the load is provided by the DCDC module (group). At this time, under the control of the system control center, the DCDC module group takes the output voltage V0 as the target control parameter and fixes it at 48V. The output current A0 is the feedforward parameter of the control system. The system control center ensures that the output current of the DCDC module group can meet the load requirements in a timely manner. If there is no charging in the middle, the system maintains this mode until the battery voltage drops to 24V (the cut-off voltage of a single battery is 1.5V, and the cut-off voltage of the battery pack is 24V), and then the system control center turns off the output and reminds the user to charge. In addition, in the boost discharge mode of the DCDC module (group), it has wide compatibility with the load. For example, when used in two-wheeled or three-wheeled electric vehicles with large load changes and complex usage scenarios, while the system control center stabilizes the output voltage V0, because the feedforward factor A0 is introduced, the entire system can meet the load requirements with a response speed of microseconds. At the same time, if the vehicle is in a braking or downhill state and the motor is in a power generation state, due to the rapid rise of V0, the system control center can determine this state based on the rising curve of V0, and the system immediately switches to the energy recovery state. The control method is as described in the above charging state. The working principle of the DCDC module group when achieving boost output is that under the control of the system control center, Figure 2 as shown in Figure 2 the circuit switches to the BOOST boost mode. At this time, the DCLL peak current sensor becomes effective. A single module operates in the per-cycle peak current control mode. The entire module group operates in the master-slave mode under the control of the system control center. The modules operate in an interleaved or synchronous manner, completely eliminating the circulating current between the modules. At this time, the entire system operates in a constant voltage mode with V0 output as the feedback loop, and the output current A0 as the feedforward quantity of the system control. Such a combination can make the response speed of the output battery reach the microsecond level, ensure the dynamic response performance of the system, and meet the usage requirements of different loads. The pump battery is the key guarantee to ensure the smooth and reliable switching of SW1 and SW2 in the K1 segmented combination switch. Especially when using electronic switches, it ensures that there is enough energy to complete the switching requirements of the switches. In any state of the battery, it ensures that the output voltage BSOUTV+ is always stable at DC 15V with respect to the positive pole of the output bus. Its working principle will not be elaborated here.

[0044] In summary, the core technical contents of the topological architecture of the present invention are as follows: 1. The topological architecture is the core point of the present invention. It can solve the problem that sodium-ion batteries cannot be fully discharged normally, while retaining the inherent characteristics of sodium-ion batteries such as high-rate charging and discharging, and greatly improving the user experience when the battery is at low voltage (the battery continuously outputs the rated voltage and responds to the load power requirements with high dynamics). For example, when using this system on a two-wheeled or three-wheeled vehicle, the user can feel that the battery has sufficient energy throughout the entire process of use, and the riding is comfortable. It can also automatically realize energy recovery during the riding process, thereby optimizing the user's electricity economic performance; in the backup power scenario, it can greatly extend the user's backup power usage time and ensure power safety. The innovations of the topology are: a) The introduction of the segmented combination switch K1 can smoothly realize the conversion of different battery states; b) The revised bidirectional DCDC module (group) is highly integrated with K1, which greatly reduces the system heat consumption and maximizes the utilization of electric energy while fully completing the battery pack charging and discharging; c) The highly real-time system control center and sampling system (A0, V0 signal) coordinate with K1 and DCDC module (group) to maximize the various battery usage scenarios, such as high dynamic load response, while retaining the inherent characteristics of sodium ion batteries, such as: high rate charging and discharging, and energy recovery in motor drive locations; d) The positive pole is shut off and the negative pole is shared. The architecture design provides hardware and software convenience for the system to adapt to different application scenarios, such as facilitating the sleep and wake-up of the battery pack, and maintaining communication with the outside world at any time without isolation; e) The innovative pump battery can ensure smooth switching of the system.

[0045] 2. This system works in a quasi-AI decision-making mode. The system control center can use, but is not limited to, advanced general-purpose MCU or DSP to achieve real-time control according to the size of the system, to complete system state identification and switching, and to complete real-time control at the same time. Specifically, there are the following aspects of work: a) Rapid state identification and accurate completion of state transitions, mainly sleep, standby, charging, discharging, and energy recovery; b) In the corresponding mode, the system control center must also complete real-time control, such as: control of the DCDC module (group), achieving voltage reduction in charging mode and meeting the requirements of the charging curve, and achieving constant voltage high dynamic output in discharge mode; c) Traditional BMS logic control, communication, power and other affairs management. In short, the system control center is the key to the realization of the whole machine function, and with excellent control algorithms, the realization of the whole machine function is completed.

[0046] 3. The current (A0) at the output terminal and the output voltage (V0) are necessary detection components to ensure the normal operation of the system. They are important components for the fast system response and to meet the power consumption conditions of the load. They are necessary parts of the topology architecture and are required to be fast, accurate, and stable. The switch SW1 and the physical object in the segmented combination switch K1 of this system can be electromagnetic mechanical switches, such as relays, etc.; they can also be power semiconductor devices, such as silicon-based MOS transistors, GAN power transistors, SIC, IGBTs, etc.; or other switches that can complete the on-off control of the battery. K1 is the core component to implement this topology architecture and is also one of the innovation points of this invention. The pump battery of this system is also manufactured with special patented technology to ensure the reliable execution of the switch SW1 and the switch SW2 in K1.

[0047] In summary, the integrated charge and discharge management topology architecture of the sodium-ion battery of this invention successfully solves the problem that the sodium-ion battery cannot be fully discharged normally due to the large voltage change range, while retaining its high-rate charge and discharge characteristics, significantly improving the user experience when the battery is at low voltage. In the backup power scenario, it greatly extends the backup power usage time and ensures power safety. The integrated topology architecture of this invention can accurately control the operation of the system. This invention uses a high-end MCU or DSP controller to build a system control center, which can accurately identify and switch system states such as sleep, standby, charging, discharging, and energy recovery, realizing super real-time control. The hardware of the control system and the adapted software work together to ensure the stable and efficient operation of the system. The integrated topology architecture of this invention is closely combined with the innovatively designed segmented control switch K1 and the improved bidirectional DCDC module (group), and is equipped with a pump battery to optimize the system function, reduce heat consumption, and improve the power utilization efficiency.

[0048] The integrated topology architecture of this invention connects the output capacitor C1, the detection component A0, and the detection component V0 in the circuit, providing a solid hardware guarantee for the high dynamic performance of the system, enabling the system to quickly respond to load changes and meet the requirements of different usage scenarios.

[0049] The integrated topology architecture of this invention has flexible charging management. The charging process of the integrated topology architecture of this invention can be subdivided into multiple characteristic controls such as trickle charging, constant current charging, floating charging, and supercharging above 2C. For different charging batteries and battery states, it flexibly adjusts the charging mode to protect the battery service life and ensure that the battery is fully charged. This is an advantage that traditional battery management systems do not have.

[0050] The integrated topology architecture of the present invention enables efficient discharge management and energy recovery. In terms of discharge management, the integrated topology architecture of the present invention can automatically switch the discharge mode according to the battery voltage, ensuring a stable output of the rated voltage when the battery is at a low voltage and meeting the power consumption requirements of high-dynamic loads. In places where the motor is driven, energy recovery can be achieved, improving the energy utilization rate of the system and optimizing the user's power consumption experience.

[0051] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structural or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present invention.

Claims

1. An integrated topology architecture of a charge and discharge protection system for a sodium-ion battery, comprising a system control center and a front-end circuit for battery state analog sampling. The front-end circuit for battery state analog sampling is connected in parallel to the battery for sampling the battery, and is connected to the system control center through a system control bus. The negative terminal of the front-end circuit for battery state analog sampling is grounded. It is characterized in that, The topology architecture further includes: A combined sectional switch K1 provided on the main battery path. The combined sectional switch K1 has a switching circuit, which is connected to the switch control pin of the system control center through a combined sectional switch status control line; Multiple DCDC bidirectional buck-boost modules connected to the system control center through a system control bus and connected in parallel. The positive poles of the first battery input ends of each DCDC bidirectional buck-boost module are connected to the output end of the combined sectional switch K1 after being serially connected with their respective detection units DCLH, and the negative poles of their first battery input ends are connected to the negative pole of the battery output after being serially connected with their respective detection units DCLL. The positive poles of the second battery input ends of each DCDC bidirectional buck-boost module are connected in parallel to the BAT+ / A1 point, and then are connected to the positive pole of the battery through the serially connected current detection component A1; A pump battery module connected to the system control center. The first end of the pump battery module is connected to the output end of the combined sectional switch K1 after being serially connected with its respective detection unit DCLH, and its second end is connected to the positive pole of the battery output and the first end of the auxiliary battery system after being serially connected with its respective detection units DCLL. The second end of the auxiliary battery system is connected to the system control center and the auxiliary battery output ends of each DCDC bidirectional buck-boost module; A detection component A0 provided on the battery output positive circuit node and is monitored in real time by the system control center. The detection component AO is a parameter for completing AI-like control, and its real-time data and converted data are used for the overall state control of the system; A detection component V0 provided between the battery output positive circuit and the negative circuit. The detection component V0 is used for real-time voltage detection, and its real-time data and converted data are used for the overall state control of the system, and it is a parameter for completing AI-like control; A polarized capacitor C1. The positive pole of the polarized capacitor C1 is connected to the positive circuit of the battery output. The polarized capacitor C1 is also connected in parallel with multiple DCDC bidirectional buck-boost modules, and its negative pole is connected to the negative circuit of the battery output.

2. The integrated topology architecture of a sodium-ion battery charge and discharge protection system according to claim 1, wherein The combined sectional switch K1 includes a diode D1, a switch SW1, and a switch SW2. The diode D1 and the switch SW1 are connected in parallel, the diode D1 is connected in series with the switch SW2. The positive pole of the diode D1 is connected to the BAT+ / A1 point and then is connected to the battery positive pole through the serially connected current detection unit A1, and its negative pole is connected to the first end of the switch SW2. The combined sectional switch status control line is connected to the corresponding control pin of the system control center to control the on-off, and its energy is provided by the dedicated pump battery.

3. The integrated topology architecture of a sodium-ion battery charge and discharge protection system according to claim 1, characterized in that, The switch SW1 and the switch SW2 form a combined switch; The switch SW1 includes one of a first mechanical switch, a first solid-state electronic switch device, and a first liquid electronic switch; The switch SW2 includes one of a second mechanical switch, a second solid-state electronic switch device, and a second liquid electronic switch.

4. The integrated topology architecture of a sodium-ion battery charge and discharge protection system according to claim 3, characterized in that, When the switch SW1 is a first mechanical switch, the first mechanical switch is a first relay; When the switch SW1 is a first solid-state electronic switch device, the first solid-state electronic switch device includes one of a MOS transistor, a GAN power device, and a SIC power device; When the switch SW2 is a second mechanical switch, the second mechanical switch is a second relay; When the switch SW2 is a second solid-state electronic switch, the second solid-state electronic switch includes one of a MOS transistor, a GAN power device, and a SIC power device.

5. The integrated topology architecture of a sodium-ion battery charge and discharge protection system according to claim 1, characterized in that, The DCDC bidirectional buck-boost module includes a DCDC bidirectional buck-boost circuit, and this DCDC bidirectional buck-boost circuit includes: A first drive module, whose drive signal terminal is connected to the system control center; MOS transistor Q1 and MOS transistor Q2. The gates of the MOS transistor Q1 and the MOS transistor Q2 are both connected to the first drive module. The source of the MOS transistor Q1 is connected to the drain of the MOS transistor Q2. After the source of the MOS transistor Q2 is connected in series with the DCLL current detection unit, it is connected to the negative pole of the battery. After the drain of the MOS transistor Q1 is connected in series with the DCLH current detection unit, it is connected to OUT+ / A, and is connected to the positive pole of the battery pack output port after passing through the detection unit A0; Inductor L1. The first end of this inductor L1 is connected to the circuit node between the drain of the MOS transistor Q1 and the source of the MOS transistor Q2, and its second end is connected to the battery BAT+ / A1 pin.

6. The integrated topology architecture of a sodium-ion battery charge and discharge protection system according to claim 1, characterized in that, The pump battery module includes: A pump battery control unit, which has an independent pump battery parameter control module. This pump battery control unit is also connected to the system control center and is controlled in real time by this system control center; A second drive module. One end of this second control module is connected to the first control end of the pump battery control unit, and its control parameters come from the pump battery control unit; MOS transistor Q3 and MOS transistor Q4. The gates of the MOS transistor Q3 and the MOS transistor Q4 are both connected to the second drive module. Among them, the source of the MOS transistor Q4 is grounded, and its drain is connected to the source of the MOS transistor Q3; Inductor L2. The first end of this inductor L2 is connected to the circuit node between the drain of the MOS transistor Q4 and the source of the MOS transistor Q3, and the second end of the inductor L2 is connected to the battery OUT+ / A point; A polarized capacitor C3. The negative pole of this polarized capacitor C3 is connected to the grounded pin of the MOS transistor Q4, and its positive pole is connected to the drain of the MOS transistor Q3 and is connected to the BSOUTV+ pin of the battery; A polarized capacitor C2. The negative pole of this polarized capacitor C2 is connected to the second end of the inductor L2, and its positive pole is connected to the drain of the MOS transistor Q3; Series-connected resistors R1 and R2. The first end after the resistors R1 and R2 are connected in series is connected to the drain of the MOS transistor Q3, and the second end after the resistors R1 and R2 are connected in series is connected to the second end of the inductor L2; Resistor R3. The first end of this resistor R3 is connected to the drain of the MOS transistor Q3; Zener diode U1. The reference pin of this zener diode U1 is connected to the circuit node between the resistors R1 and R2, its second pin is connected to the second end of the inductor L2, and its third pin is connected to the second end of the resistor R3; Series-connected resistors R4 and R5. The first end after the resistors R4 and R5 are connected in series is connected to the drain of the MOS transistor Q3, and the second end after the resistors R4 and R5 are connected in series is connected to the circuit node between the zener diode U1 and the resistor R3; Optocoupler device U2, the positive electrode of the light-emitting end of the optocoupler device U2 is connected to the circuit node between the resistor R4 and the resistor R5, the negative electrode of its light-emitting end is connected to the second end after the resistor R4 and the resistor R5 are connected in series, the collector of its light-receiving end is connected to the second control end of the pump battery control unit, and the emitter of its light-receiving end is connected to the third control end of the pump battery control unit.

7. An integrated topology architecture of a charge and discharge protection system for a sodium-ion battery according to any one of claims 1-6, characterized in that The system control center includes one of an MCU real-time control device and a DSP real-time control device.

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