A battery heating control circuit and energy storage power supply

Abstract

The utility model discloses a kind of battery heating control circuit and energy storage power supply. The battery heating control circuit includes temperature detection unit, hysteresis comparison unit, switching unit and heating unit;Temperature detection unit is in response to battery temperature output first comparison voltage;Hysteresis comparison unit outputs on signal when first comparison voltage is greater than first preset voltage threshold, and output off signal when first comparison voltage is less than second preset voltage threshold, wherein first preset voltage threshold is greater than second preset voltage threshold;Switching unit is in response to on signal and turns on heating loop to make heating unit for battery heating, in response to off signal and disconnect heating loop to stop heating. The utility model embodiment is realized battery automatic heating control by pure hardware circuit, can simplify circuit, reduce cost, improve response speed and anti-interference ability and avoid software fault risk, solve the program vulnerability of traditional software control mode, sensor misjudgment and other problems.

Description

Technical Field

[0001] This utility model relates to the field of battery heating control circuit and energy storage power supply. Background Technology

[0002] Lithium-ion batteries, as a primary energy storage device, face numerous technical challenges in low-temperature environments. Firstly, the chemical reaction rate of the battery decreases significantly at low temperatures, leading to increased internal resistance and reduced discharge capacity. Studies have shown that the discharge capacity of lithium-ion batteries can decrease by 20% to 30% below 0°C, resulting in a substantial reduction in output power and severely impacting device startup performance or shortening battery life.

[0003] Secondly, there are safety hazards during low-temperature charging. When charging at low temperatures, lithium ions are prone to deposit on the negative electrode surface, forming metallic lithium (lithium plating). This not only reduces battery capacity but may also puncture the separator, causing internal short circuits or even thermal runaway. Furthermore, prolonged operation at low temperatures accelerates structural damage to electrode materials, such as graphene peeling, and the electrolyte may solidify or decompose, further accelerating battery capacity decay and aging.

[0004] To address the aforementioned issues, battery heating technology is currently widely adopted. Existing battery heating control schemes primarily rely on software implementation. A typical workflow is as follows: temperature sensor signals are acquired via an analog-to-digital converter (ADC), and the actual temperature value is calculated after digital signal processing such as filtering and calibration. Then, the software algorithm determines and issues control commands to drive switching devices such as MOSFETs or relays, thereby controlling the heating element to heat the battery.

[0005] However, existing software control solutions have significant drawbacks. First, the software system itself is prone to failure, including program vulnerabilities, memory overflows, algorithm errors, and misinterpretations of temperature sensor signals. These issues can lead to heating control failure or uncontrolled heating, posing safety risks. Second, this solution heavily relies on the stable operation of the microcontroller unit (MCU) or battery management system (BMS). If the main control chip fails due to electrostatic discharge, firmware corruption, or other reasons, the entire heating function will be completely paralyzed, failing to provide the necessary low-temperature protection for the battery. Utility Model Content

[0006] The main technical problem solved by this utility model embodiment is to provide a battery heating control circuit and an energy storage power supply, which can solve at least some of the defects of existing battery heating circuits.

[0007] In a first aspect, this utility model provides a battery heating control circuit, including: a temperature detection unit, a hysteresis comparison unit, a switching unit, and a heating unit; the hysteresis comparison unit is connected to both the temperature detection unit and the switching unit, and the switching unit is also connected to the heating unit; the temperature detection unit is configured to output a first comparison voltage in response to the battery temperature; the hysteresis comparison unit is configured to output a conduction signal when the first comparison voltage is greater than a first preset voltage threshold; and to output a shutdown signal when the first comparison voltage is less than a second preset voltage threshold; the switching unit is configured to conduct a heating circuit between the heating unit and the battery in response to the conduction signal, so that the heating unit heats the battery; and to disconnect the heating circuit in response to the shutdown signal, so that the heating unit stops heating; the first preset voltage threshold is greater than the second preset voltage threshold.

[0008] Optionally, when the first comparison voltage drops from greater than the first preset voltage threshold to less than the first preset voltage threshold, the hysteresis comparison unit maintains the output of the on signal until the first comparison voltage is less than the second preset voltage threshold; when the first comparison voltage drops from less than the second preset voltage threshold to greater than the second preset voltage threshold, the hysteresis comparison unit maintains the output of the off signal until the first comparison voltage is greater than the first preset voltage threshold.

[0009] Optionally, when the battery temperature is lower than a first preset temperature threshold, the first comparison voltage is greater than the first preset voltage threshold; when the battery temperature is higher than a second preset temperature, the first comparison voltage is less than the second preset voltage threshold.

[0010] Optionally, the hysteresis comparator unit includes resistors R1, R2, and R8, a Zener diode DZ2, and an operational amplifier U1A. The first end of resistor R1 and the second end of resistor R2 are connected to the power supply. The second end of resistor R1, the cathode of the Zener diode DZ2, and the output of the operational amplifier U1A are all connected to the input of the switching unit. The first end of resistor R2 and the second end of resistor R8 are both connected to the non-inverting input of the operational amplifier U1A. The inverting input of the operational amplifier U1A is connected to the output of the temperature detection unit. The positive terminal of the power input of the operational amplifier U1A is connected to the power supply. The negative terminal of the power input of the operational amplifier U1A, the first end of resistor R8, and the anode of the Zener diode DZ2 are connected to ground.

[0011] Optionally, the switching unit includes resistors R9, R10, and R12, a Zener diode DZ1, a switching transistor Q1, and a switching transistor Q2; the first end of resistor R9 and the emitter of the switching transistor Q1 are connected to the power supply, the second end of resistor R9 and the second end of resistor R10 are connected to the output of the hysteresis comparator unit, the base of the switching transistor Q1 is connected to the first end of resistor R10; the collector of the switching transistor Q1, the cathode of the Zener diode DZ1, and the first end of resistor R12 are all connected to the gate of the switching transistor Q2, the drain of the switching transistor Q2 is connected to the first end of the heating unit, and the source of the switching transistor Q2, the anode of the Zener diode DZ1, and the second end of resistor R12 are all connected to the negative terminal of the battery.

[0012] Optionally, the switching transistor Q1 is a PNP transistor, and the switching transistor Q2 is an N-channel metal-oxide-semiconductor field-effect transistor.

[0013] Optionally, the heating unit includes resistors R3, R4, R5, R6, R7, and fuse F1; the first ends of resistors R3, R4, R5, R6, and R7 are all connected to the second end of fuse F1, the first end of fuse F1 is connected to the positive terminal of the battery, and the second ends of resistors R3, R4, R5, R6, and R7 are all connected to the output terminal of the switching unit.

[0014] Optionally, the temperature detection unit includes a resistor R11 and a thermistor RT1; the first end of the resistor R11 is connected to the power supply, the second end of the resistor R11 and the first end of the thermistor RT1 are both connected to the input terminal of the hysteresis comparison unit, and the second end of the thermistor RT1 is connected to the reference ground.

[0015] Optionally, the thermistor RT1 is a negative temperature coefficient thermistor.

[0016] Secondly, embodiments of the present invention provide an energy storage power supply, comprising: a battery; and a battery heating control circuit as described in the first aspect.

[0017] The beneficial effects of this utility model embodiment are as follows: Unlike the prior art, this utility model embodiment realizes automatic battery heating control through pure hardware circuit, which can simplify the circuit, reduce costs, improve response speed and anti-interference ability, and avoid software failure risks, thus solving the problems of program loopholes and sensor misjudgment that exist in traditional software control methods. Attached Figure Description

[0018] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0019] Figure 1 This is a schematic diagram of the structure of a battery heating control circuit provided by an embodiment of the present invention;

[0020] Figure 2 This is a circuit diagram of a battery heating control circuit provided by an embodiment of the present invention. Detailed Implementation

[0021] To facilitate understanding of this utility model, a more detailed description is provided below with reference to the accompanying drawings and specific embodiments. It should be noted that when an element is described as being "fixed to" another element, it can be directly on the other element, or one or more intermediate elements may exist between them. When an element is described as being "connected" to another element, it can be directly connected to the other element, or one or more intermediate elements may exist between them. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this specification are for illustrative purposes only.

[0022] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.

[0023] In some embodiments of this application, a battery heating control circuit is provided, the schematic diagram of which is shown below. Figure 1 As shown. Specifically, the battery heating control circuit includes a temperature detection unit 110, a hysteresis comparison unit 120, a switching unit 130, and a heating unit 140. The hysteresis comparison unit 120 is connected to both the temperature detection unit 110 and the switching unit 130, and the switching unit 130 is also connected to the heating unit 140.

[0024] In some embodiments of this application, the temperature detection unit 110 is configured to output a corresponding first comparison voltage in response to changes in battery temperature. By way of example and not limitation, the temperature detection unit 110 may employ a temperature-sensitive element to achieve temperature-to-voltage conversion. When the ambient temperature of the battery changes, the electrical characteristics of the temperature-sensitive element change accordingly. Through appropriate circuit design, the temperature change can be converted into a voltage signal change, thereby providing a voltage reference for subsequent comparison and judgment.

[0025] In some embodiments of this application, the hysteresis comparison unit 120 is configured to output a corresponding control signal based on the comparison result of the received first comparison voltage and a preset voltage threshold. Specifically, when the first comparison voltage is greater than the first preset voltage threshold, the hysteresis comparison unit 120 outputs a turn-on signal; when the first comparison voltage is less than the second preset voltage threshold, the hysteresis comparison unit 120 outputs a turn-off signal. The first preset voltage threshold being greater than the second preset voltage threshold forms a voltage hysteresis window, effectively avoiding frequent switching operations caused by small voltage fluctuations.

[0026] The hysteresis comparator 120 has significant hysteresis characteristics. In some embodiments of this application, when the first comparison voltage drops from above a first preset voltage threshold to below a first preset voltage threshold, the hysteresis comparator 120 maintains the output of the on signal until the first comparison voltage drops below a second preset voltage threshold. Correspondingly, when the first comparison voltage rises from below a second preset voltage threshold to above a second preset voltage threshold, the hysteresis comparator 120 maintains the output of the off signal until the first comparison voltage rises above a first preset voltage threshold.

[0027] Specifically, the switching unit 130 is configured to respond to the output signal of the hysteresis comparator unit 120 and control the on / off state of the heating circuit. When a conduction signal is received, the switching unit 130 conducts the heating circuit between the heating unit 140 and the battery, causing the heating unit 140 to begin heating the battery. When a shutdown signal is received, the switching unit 130 disconnects the heating circuit, causing the heating unit 140 to stop heating. By way of example and not limitation, the switching unit 130 can employ electronic switching devices to achieve fast and reliable switching action.

[0028] In some embodiments of this application, the heating unit 140 is electrically connected to the switching unit 130 and is configured to heat the battery when the heating circuit is turned on. Specifically, the heating unit 140 receives electrical energy from the battery and converts it into heat energy, thereby increasing the battery temperature through heat conduction. By way of example and not limitation, the heating unit 140 may be placed near the battery or in direct contact with the battery to achieve efficient heat transfer.

[0029] Specifically, a defined correspondence exists between temperature and voltage in this battery heating control circuit. When the battery temperature is below a first preset temperature threshold, the first comparison voltage is greater than the first preset voltage threshold, triggering heating to start; when the battery temperature is above a second preset temperature, the first comparison voltage is less than the second preset voltage threshold, triggering heating to stop. As an example, and not a limitation, the first preset temperature threshold can be set to 5°C, and the second preset temperature to 20°C, to achieve a control strategy that automatically starts heating when the battery temperature is below 5°C and automatically stops heating when the temperature reaches 20°C.

[0030] In some embodiments of this application, a direct electrical connection is established between the heating unit 140 and the battery. Specifically, the power input terminal of the heating unit 140 is connected to the positive terminal of the battery to obtain the electrical energy required for heating. It is easy to understand that the other end of the heating unit 140 forms a complete heating circuit with the negative terminal of the battery through the switching unit 130. By way of example and not limitation, when the switching unit 130 is in the on state, current flows from the positive terminal of the battery through the heating unit 140, and then returns to the negative terminal of the battery through the on switching unit 130, forming a closed heating current circuit.

[0031] In some embodiments of this application, the output terminal of the switching unit 130 is electrically connected to the negative terminal of the battery, and its input terminal receives a control signal from the hysteresis comparator unit 120. The switching unit 130 determines the on / off state of the heating circuit based on the state of the control signal, thereby controlling whether the heating unit 140 can obtain electrical energy from the battery for heating operation.

[0032] In some embodiments of this application, the battery heating control circuit is further provided with a power supply control mechanism to ensure the safe and reliable operation of the heating function. Specifically, the positive terminal of the battery can only be connected to the power input terminal of the heating unit 140 when the main drive MOS of the BMS control loop is closed, so that the heating unit 140 can be powered normally and the automatic heating function can work normally.

[0033] As an example and not a limitation, when the BMS management system detects abnormal operating conditions, such as charging overcurrent, discharging overcurrent, short circuit, or communication failure, the BMS will automatically shut down the main MOS circuit, causing the power input terminal of the heating unit 140 to disconnect from the positive terminal of the battery. The heating unit 140 will lose its voltage supply, and the entire heating function will fail. This avoids the erroneous operation of continuing heating under abnormal battery system conditions and improves the safety of the entire power system.

[0034] In some embodiments of this application, a battery heating control circuit is provided, the circuit schematic of which is shown below. Figure 2As shown. Specifically, the temperature detection unit 110 includes a resistor R11 and a thermistor RT1. In some embodiments of this application, the first end of the resistor R11 is connected to a 12V power supply, and the second end of the resistor R11 and the first end of the thermistor RT1 are both connected to the input terminal of the hysteresis comparator unit 120. The second end of the thermistor RT1 is connected to the reference ground GND.

[0035] As an example and not a limitation, thermistor RT1 is a negative temperature coefficient thermistor (NTC), meaning its resistance is negatively correlated with temperature. When the ambient temperature decreases, the resistance of thermistor RT1 increases; when the ambient temperature increases, the resistance of thermistor RT1 decreases. It is easy to understand that resistor R11 and thermistor RT1 form a voltage divider circuit, and the voltage at the divider point is the first comparison voltage, which changes with temperature.

[0036] For example, when the battery temperature is 5°C, the resistance of the thermistor RT1 is approximately 22kΩ; when the battery temperature is 20°C, the resistance of the thermistor RT1 is approximately 12kΩ. By appropriately selecting the resistance value of resistor R11, a suitable voltage division ratio can be set so that the first comparison voltage output by the temperature detection unit 110 can accurately reflect the change in battery temperature.

[0037] In some embodiments of this application, the hysteresis comparator unit 120 includes resistors R1, R2, and R8, a Zener diode DZ2, and an operational amplifier U1A. Specifically, the first end of resistor R1 and the second end of resistor R2 are connected to a 12V power supply, and the second end of resistor R1, the cathode of Zener diode DZ2, and the output terminal of operational amplifier U1A are all connected to the input terminal of switching unit 130.

[0038] The first terminal of resistor R2 and the second terminal of resistor R8 are both connected to the non-inverting input (U+) terminal of operational amplifier U1A, and the inverting input (U-) terminal of operational amplifier U1A is connected to the output terminal of temperature detection unit 110. By way of example and not limitation, the positive power supply terminal (VCC) of operational amplifier U1A is connected to a 12V power supply, and the negative power supply terminal (VEE) of operational amplifier U1A, the first terminal of resistor R8, and the anode of Zener diode DZ2 are all connected to reference ground GND.

[0039] In some embodiments of this application, when the voltage at the inverting input terminal of operational amplifier U1A is greater than the voltage at the non-inverting input terminal, operational amplifier U1A outputs a low level (0V), i.e., a turn-on signal; when the voltage at the inverting input terminal of operational amplifier U1A is less than the voltage at the non-inverting input terminal, operational amplifier U1A outputs a high level (12V), i.e., a turn-off signal.

[0040] Specifically, resistors R1, R2, and R8 form a positive feedback network, providing hysteresis characteristics for operational amplifier U1A. When the output of operational amplifier U1A is high, the positive feedback from resistor R1 causes the voltage at the non-inverting input to rise, forming the upper threshold VH; when the output of operational amplifier U1A is low, the voltage at the non-inverting input decreases, forming the lower threshold VL. VH and VL correspond to the first preset voltage threshold and the second preset voltage threshold, respectively.

[0041] The Zener diode DZ2 ensures the stability of the output voltage of operational amplifier U1A. When the output voltage attempts to exceed the Zener diode DZ2's regulation value, the Zener diode DZ2 conducts, clamping the output voltage to a stable level and protecting subsequent circuitry from overvoltage damage.

[0042] In some embodiments of this application, the switching unit 130 includes resistors R9, R10, and R12, a Zener diode DZ1, a switching transistor Q1, and a switching transistor Q2. In some embodiments of this application, the first terminal of resistor R9 and the emitter of switching transistor Q1 are connected to a 12V power supply, the second terminals of resistor R9 and R10 are connected to the output terminal of the hysteresis comparator unit 120, and the base of switching transistor Q1 is connected to the first terminal of resistor R10.

[0043] By way of example and not limitation, switch Q1 is a PNP transistor, and switch Q2 is an N-channel metal-oxide-semiconductor field-effect transistor (N-MOSFET). Specifically, the collector of switch Q1, the cathode of Zener diode DZ1, and the first terminal of resistor R12 are all connected to the gate of switch Q2. The drain of switch Q2 is connected to the first terminal of heating unit 140. The source of switch Q2, the anode of Zener diode DZ1, and the second terminal of resistor R12 are all connected to the negative terminal of the battery.

[0044] Specifically, when the hysteresis comparator 120 outputs a low level (0V), the base of the PNP transistor Q1 is pulled to ground potential through resistor R10. Since the emitter is connected to the 12V power supply, a forward bias is formed between the base and emitter, and the PNP transistor Q1 is turned on. In some embodiments of this application, after the PNP transistor Q1 is turned on, its collector outputs a high level (approximately 12V). This high level is applied to the gate of the N-MOSFET Q2 through the Zener diode DZ1, causing the N-MOSFET Q2 to turn on, thereby connecting the heating circuit.

[0045] It's easy to understand that when the hysteresis comparator 120 outputs a high level (12V), the base potential and emitter potential of the PNP transistor Q1 are close, and there is no forward bias between the base and emitter, so the PNP transistor Q1 is turned off. After the PNP transistor Q1 is turned off, there is no current output from its collector, and the gate potential of the N-MOSFET Q2 is pulled down to ground potential through resistor R12, so the N-MOSFET Q2 is turned off, disconnecting the heating circuit.

[0046] Specifically, resistor R9 provides appropriate operating current for PNP transistor Q1, while resistor R10 serves as current limiting and level shifting. In some embodiments of this application, the combination of Zener diode DZ1 and resistor R12 ensures stable gate voltage for N-MOSFET Q2, prevents gate overvoltage breakdown, and provides a reliable turn-off path.

[0047] In some embodiments of this application, the heating unit 140 includes resistors R3, R4, R5, R6, and R7, and a fuse F1. Specifically, the first ends of resistors R3, R4, R5, R6, and R7 are all connected to the second end of fuse F1, and the first end of fuse F1 is connected to the positive terminal of the battery.

[0048] The second terminals of resistors R3, R4, R5, R6, and R7 are all connected to the output terminal of switching unit 130, i.e., the source of N-MOSFET Q2. Resistors R3 to R7 are connected in parallel to form a heating load. When switching unit 130 is turned on, current flows from the positive terminal of the battery through fuse F1 into each parallel resistor, and then returns to the negative terminal of the battery through the turned-on N-MOSFET Q2, forming a complete heating current loop.

[0049] Specifically, fuse F1 provides crucial safety protection. When an abnormally high current occurs in the heating circuit, such as due to a short circuit or overcurrent caused by component failure, fuse F1 will melt promptly, cutting off the heating circuit and preventing the abnormally high current from burning out circuit components or causing a safety accident. In some embodiments of this application, by selecting a suitable fuse F1, an appropriate protection threshold can be set between normal heating current and abnormal overcurrent.

[0050] The following is an exemplary description of the working principle of the battery heating control circuit: When the battery temperature is below 5°C, the resistance of the thermistor RT1 increases to approximately 22kΩ, causing the first comparison voltage output by the temperature detection unit 110 to rise. Specifically, when the first comparison voltage is greater than the first preset voltage threshold of the hysteresis comparison unit 120, the voltage at the inverting input terminal of the operational amplifier U1A is higher than the voltage at the non-inverting input terminal, and the operational amplifier U1A outputs a low level.

[0051] It's easy to understand that the low-level signal output from operational amplifier U1A is transmitted to switching unit 130, causing PNP transistor Q1 to conduct, which in turn drives N-MOSFET Q2 to conduct, connecting the heating circuit. As an example, and not a limitation, current flows from the positive terminal of the battery through fuse F1 into parallel resistor R3 to resistor R7, and then returns to the negative terminal of the battery through the conducting N-MOSFET Q2. The resistor heats up, thus heating the battery.

[0052] Specifically, as the heating process proceeds, the battery temperature gradually increases, and the resistance of the thermistor RT1 decreases accordingly, causing the first comparison voltage to drop. When the battery temperature reaches 20°C, the resistance of the thermistor RT1 decreases to approximately 12kΩ, and the first comparison voltage drops below the second preset voltage threshold of the hysteresis comparator unit 120. At this time, the voltage at the inverting input terminal of operational amplifier U1A is lower than the voltage at the non-inverting input terminal, and operational amplifier U1A outputs a high level.

[0053] It is easy to understand that the high-level signal output by operational amplifier U1A causes PNP transistor Q1 to turn off, which in turn causes N-MOSFET Q2 to turn off, disconnecting the heating circuit and stopping the heating of the battery. As an example and not a limitation, because the hysteresis comparator 120 has hysteresis characteristics, the circuit output state remains stable when the temperature fluctuates between two threshold values, avoiding frequent switching operations.

[0054] Unlike existing technologies, this utility model embodiment achieves automatic battery heating control through a pure hardware circuit, which simplifies the circuit, reduces costs, improves response speed and anti-interference ability, and avoids the risk of software failure. It solves the problems of program vulnerabilities and sensor misjudgment that exist in traditional software control methods.

[0055] Based on the battery heating control circuit provided in the above embodiments, this utility model also provides an energy storage power supply, which includes a battery and the battery heating control circuit as described in any of the foregoing embodiments.

[0056] As the core energy storage unit of an energy storage power source, the battery is responsible for storing and releasing electrical energy. As an example and not a limitation, the battery can be a lithium-ion battery, a lithium iron phosphate battery, or other types of rechargeable batteries; the appropriate battery type, capacity, and voltage level should be selected based on specific application requirements.

[0057] In some embodiments of this application, the battery heating control circuit is integrated with the battery in the same energy storage power system, forming an intelligent energy storage device with automatic temperature regulation function. Specifically, the temperature detection unit 110 of the battery heating control circuit is close to or in contact with the battery surface to monitor battery temperature changes in real time; the heating unit 140 is located near the battery or thermally coupled to the battery to ensure effective transfer of heating effect. When the ambient temperature is low and the battery temperature drops, the battery heating control circuit automatically activates the heating function to maintain the battery temperature within a suitable operating range, thereby ensuring the normal operation performance of the energy storage power supply in low-temperature environments.

[0058] It should be noted that while the preferred embodiments of this utility model are provided in the specification and accompanying drawings, this utility model can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are not intended to impose additional limitations on the content of this utility model; their purpose is to provide a more thorough and comprehensive understanding of the disclosure of this utility model. Furthermore, the above-described technical features can be combined with each other to form various embodiments not listed above, all of which are considered to be within the scope of this utility model specification. Moreover, those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A battery heating control circuit, characterized in that, include: Temperature detection unit, hysteresis comparison unit, switching unit, and heating unit; The hysteresis comparison unit is connected to the temperature detection unit and the switching unit respectively, and the switching unit is also connected to the heating unit; The temperature detection unit is configured to output a first comparison voltage in response to the battery temperature; The hysteresis comparison unit is configured to output a conduction signal when the first comparison voltage is greater than a first preset voltage threshold. And when the first comparison voltage is less than the second preset voltage threshold, a shutdown signal is output; The switching unit is configured to activate the heating circuit between the heating unit and the battery in response to the conduction signal, so that the heating unit heats the battery. And in response to the shutdown signal, disconnect the heating circuit to stop the heating unit from heating; The first preset voltage threshold is greater than the second preset voltage threshold.

2. The circuit of claim 1, wherein, When the first comparison voltage drops from being greater than the first preset voltage threshold to being less than the first preset voltage threshold, the hysteresis comparison unit maintains the output of the conduction signal until the first comparison voltage is less than the second preset voltage threshold. When the first comparison voltage drops from less than the second preset voltage threshold to greater than the second preset voltage threshold, the hysteresis comparison unit maintains the output of the turn-off signal until the first comparison voltage is greater than the first preset voltage threshold.

3. The circuit of claim 1, wherein, When the battery temperature is lower than a first preset temperature threshold, the first comparison voltage is greater than the first preset voltage threshold; When the battery temperature is higher than the second preset temperature, the first comparison voltage is less than the second preset voltage threshold.

4. The circuit of claim 1, wherein, The hysteresis comparator unit includes resistors R1, R2, and R8, a Zener diode DZ2, and an operational amplifier U1A; The first end of resistor R1 and the second end of resistor R2 are connected to the power supply. The second end of resistor R1, the cathode of Zener diode DZ2, and the output of operational amplifier U1A are all connected to the input of the switching unit. The first end of resistor R2 and the second end of resistor R8 are both connected to the non-inverting input of operational amplifier U1A. The inverting input of operational amplifier U1A is connected to the output of the temperature detection unit. The positive terminal of the power input of operational amplifier U1A is connected to the power supply. The negative terminal of the power input of operational amplifier U1A, the first end of resistor R8, and the anode of Zener diode DZ2 are connected to the reference ground.

5. The circuit of claim 1, wherein, The switching unit includes resistors R9, R10, and R12, a Zener diode DZ1, a switching transistor Q1, and a switching transistor Q2. The first end of the resistor R9 and the emitter of the switch Q1 are connected to the power supply. The second end of the resistor R9 and the second end of the resistor R10 are connected to the output of the hysteresis comparator. The base of the switch Q1 is connected to the first end of the resistor R10. The collector of the switching transistor Q1, the cathode of the Zener diode DZ1, and the first terminal of the resistor R12 are all connected to the gate of the switching transistor Q2. The drain of the switching transistor Q2 is connected to the first terminal of the heating unit. The source of the switching transistor Q2, the anode of the Zener diode DZ1, and the second terminal of the resistor R12 are all connected to the negative terminal of the battery.

6. The circuit of claim 5, wherein, The switching transistor Q1 is a PNP transistor, and the switching transistor Q2 is an N-channel metal-oxide-semiconductor field-effect transistor.

7. The circuit of claim 1, wherein, The heating unit includes resistors R3, R4, R5, R6, and R7, as well as fuse F1; The first ends of resistors R3, R4, R5, R6, and R7 are all connected to the second end of fuse F1. The first end of fuse F1 is connected to the positive terminal of the battery. The second ends of resistors R3, R4, R5, R6, and R7 are all connected to the output terminal of the switching unit.

8. The circuit of claim 1, wherein, The temperature detection unit includes a resistor R11 and a thermistor RT1; The first end of the resistor R11 is connected to the power supply, the second end of the resistor R11 and the first end of the thermistor RT1 are both connected to the input of the hysteresis comparator, and the second end of the thermistor RT1 is connected to the reference ground.

9. The circuit of claim 8, wherein, The thermistor RT1 is a negative temperature coefficient thermistor.

10. An energy storage power supply, characterized by, include: Battery; And the battery heating control circuit as described in any one of claims 1-9.

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