A charger with a battery heating function

Abstract

The present invention relates to the field of chargers, and discloses a charger with a battery heating function. The key points of its technical solution include a charging module, a heating module, a temperature acquisition module, a heating control module, and a charging performance evaluation module. The charging module is used to charge the battery; the heating module is used to heat the battery; the temperature acquisition module is used to acquire the ambient temperature and the battery temperature; the heating control module is configured with a preheating strategy. The heating control module calculates the ambient heat dissipation efficiency, the heater efficiency, and the heat generated during charging according to the preheating strategy to obtain a temperature correlation, and the temperature correlation reflects the relationship between the heater power, the charging power, and the battery charging temperature; the charging performance evaluation module is pre-trained with a charging performance evaluation model. Based on the charging performance evaluation model, a target charging temperature is obtained and output to the heating control module so that the heater heats at a target power, and the target power and the target charging temperature conform to the temperature correlation.

Description

Technical Field

[0001] The invention relates to the field of chargers, and more particularly to a charger with a battery heating function. Background Art

[0002] In today's transportation sector, electric bicycles have rapidly gained widespread popularity around the world due to their convenience and environmental friendliness. As one of the main power sources for electric bicycles, the performance of lead-acid batteries is directly related to the user experience and market development of electric bicycles. With the continuous growth of the number of electric bicycles, research on the performance optimization of lead-acid batteries has become increasingly in-depth. The charging and discharging performance of lead-acid batteries is extremely sensitive to the ambient temperature of use. Especially in the cold winter, the low temperature environment will significantly deteriorate the charging and discharging performance of the battery, thereby seriously shortening the mileage of the electric bicycle. To solve this problem, designers proposed the idea of installing a heating device inside the battery to heat the battery. This idea attempts to improve the performance of the battery in a low temperature environment to a certain extent, but it has exposed many disadvantages in actual applications.

[0003] From a cost perspective, purchasing heating modules independently undoubtedly greatly increases the cost of batteries. Each battery needs to be equipped with a dedicated heating module, which not only increases the cost of raw material procurement, but also increases the overall production and assembly cost of the battery, causing the terminal price of electric bicycles to rise, which to a certain extent affects the market competitiveness of the product; in terms of reliability and safety, once the heating module fails, it will cause a series of serious problems. If the heating module fails and causes it to continue to heat the battery, the battery temperature will continue to rise, and may eventually be damaged due to overheating, directly shortening the service life of the battery. What's more serious is that the continuous heating and discharge of the heating module will cause the battery to be seriously depleted, which will not only prevent users from using the electric bicycle normally, but may even cause the battery to be scrapped. Moreover, long-term heating and discharge are also very likely to cause serious accidents such as fires, posing a huge threat to the safety of users' lives and property; maintenance convenience is also a major problem. Since the heating module is installed inside the battery, when a failure occurs, maintenance personnel need to disassemble the battery, which is complicated and time-consuming. This not only increases the maintenance cost, but may also cause secondary damage to the battery due to improper maintenance, further affecting the battery performance and life. From the perspective of charging management, since the heating circuit is set at the battery end, the charger cannot obtain the battery temperature information in real time, and it is difficult to perform corresponding charging management accordingly. In this case, once the battery temperature rises abnormally during the charging process, the charger cannot adjust the charging strategy in time, which greatly increases the risk of thermal runaway of the battery. Once thermal runaway occurs, it will have catastrophic consequences for the battery and even the entire electric bicycle system. Summary of the invention

[0004] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a charger with a battery heating function, which is used to overcome the above-mentioned defects in the prior art, improve the charging and discharging performance of the battery in a low-temperature environment, and ensure the stable operation and use safety of electric bicycles.

[0005] To achieve the above purpose, the present invention provides the following technical solutions:

[0006] A charger with a battery heating function, comprising

[0007] a charging module, which is used to charge the battery;

[0008] a heating module, which is used to heat the battery;

[0009] a temperature acquisition module, which is used to acquire the ambient temperature and the battery temperature;

[0010] a heating control module, which is configured with a preheating strategy. The heating control module calculates the ambient heat dissipation efficiency, the heater efficiency, and the charging heat generation according to the preheating strategy to obtain a temperature correlation, and the temperature correlation reflects the relationship between the heater power, the charging power, and the battery charging temperature;

[0011] a charging performance evaluation module, which is pre-trained with a charging performance evaluation model. Based on the charging performance evaluation model, the target charging temperature is obtained and output to the heating control module so that the heater heats according to the target power, and the target power and the target charging temperature conform to the temperature correlation.

[0012] In the present invention, preferably, the preheating strategy includes

[0013] successively obtaining a first temperature change curve, a second temperature change curve, and a third temperature change curve. The first temperature curve is specifically the curve of the battery temperature changing with time during the process of controlling the heating module to heat the battery with a first heater power. The second temperature change curve is specifically the curve of the battery temperature changing with time during the cooling process after the heating module stops working. The third temperature change curve is specifically the curve of the battery temperature changing with time during the process of the charging module working and the heating module controlling the heating module to heat the battery with a second heater power;

[0014] Calculating the ambient heat dissipation efficiency and the heater efficiency based on the first temperature change curve and the second temperature change curve;

[0015] Calculating the charging heat generation based on the third temperature change curve.

[0016] In the present invention, preferably, the charging performance evaluation module collects battery parameters at different battery temperatures. The battery parameters include charging efficiency, charging speed, battery internal resistance, and battery aging degree. The battery parameters are input into a charging performance evaluation model to obtain a charging performance score. The charging performance scores at different battery temperatures are compared, and the battery temperature with the highest charging performance score is used as the target charging temperature.

[0017] In the present invention, preferably, the calculation formula of the charging performance evaluation model is specifically

[0018] ;

[0019] where Q represents the charging performance score, represents the charging efficiency, S represents the charging speed, R represents the battery internal resistance, and A represents the battery aging degree.

[0020] In the present invention, preferably, the calculation formula of the environmental heat dissipation efficiency is as follows:

[0021] ;

[0022] where represents the environmental heat dissipation efficiency, m represents the mass of the battery; c represents the specific heat capacity of the battery material; represents the decrease in battery temperature during the cooling process; represents the average temperature difference between the battery and the environment during the cooling process; represents the heat dissipation coefficient; A represents the surface area of contact between the battery and the environment; represents the cooling duration.

[0023] In the present invention, preferably, the calculation formula of the heater efficiency is as follows:

[0024] ;

[0025] where represents the heater efficiency, represents the increase in battery temperature during the heating process; P represents the heater power; represents the heating duration.

[0026] In the present invention, preferably, the heating control module is configured with a temperature intervention strategy. When the change rate of the environmental temperature is greater than a preset temperature change rate, the heater power is adjusted based on the temperature intervention strategy. The temperature intervention strategy includes reducing the heater power, judging the change in battery temperature. If the battery temperature shows a decreasing trend, the heater power is gradually increased until the battery temperature is stable. If the battery temperature still shows an increasing trend, the heater power is gradually decreased until the battery temperature is stable, and the correlation between the environmental heat dissipation efficiency and the environmental temperature is recorded.

[0027] Advantages of the present invention:

[0028] 1. Before formal charging, the present invention pre-heats the battery to a certain temperature and then cools it, so as to calculate the environmental heat dissipation efficiency and the heater efficiency. Then, by charging, the heat generated during charging can be obtained. Thus, the temperature correlation can be obtained, that is, the relationship between the heater power, the charging power and the battery charging temperature. Then, by judging the correlation between the charging performance and the charging temperature during battery charging, the heater power is set, so that the battery can be charged with the optimal charging performance;

[0029] 2. In the step of obtaining the temperature correlation by the heating control module according to the pre-heating strategy to calculate the environmental heat dissipation efficiency, the heater efficiency and the heat generated during charging, first, the first, second and third temperature change curves are obtained in sequence. Based on these curves, the environmental heat dissipation efficiency, the heater efficiency and the heat generated during charging are calculated respectively, realizing the quantification of the relationship between multiple key factors affecting the battery temperature, which helps the charger to accurately master the relationship between the heater power, the charging power and the battery charging temperature under different conditions, and can more accurately adjust the heating and charging parameters according to the actual environment and the characteristics of the battery itself, achieving the effect of improving the accuracy of the heating and charging processes, avoiding damage to the battery caused by improper heating or charging, and improving the battery charging efficiency and service life;

[0030] 3. By giving the specific calculation formula of the charging performance evaluation model, the quantification and comprehensive evaluation of multiple battery performance parameters are realized. The charging performance score calculated by this formula can intuitively reflect the comprehensive performance of the battery at different battery temperatures, providing a scientific and accurate quantitative basis for determining the target charging temperature, avoiding the subjectivity and uncertainty of human experience judgment, being beneficial to improving the accuracy of performance judgment and enhancing the battery performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is the structural schematic diagram of the present invention;

[0032] Figure 2 is the structural schematic diagram of the power conversion unit in the present invention;

[0033] Figure 3 is the structural schematic diagram of the battery heating unit in the present invention;

[0034] Figure 4 is the structural schematic diagram of the constant current and constant voltage control unit in the present invention;

[0035] Figure 5 is the structural schematic diagram of the MCU control unit in the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0036] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all 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.

[0037] It should be noted that when a component is referred to as being "fixed to" another component, it can be directly on the other component or there may also be an intermediate component. When a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be an intermediate component at the same time. When a component is considered to be "disposed on" another component, it can be directly disposed on the other component or there may be an intermediate component at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0039] Please also refer to Figures 1 to 5 , this embodiment provides a charger with a battery heating function, including

[0040] a charging module for charging the battery;

[0041] a heating module for heating the battery;

[0042] a temperature acquisition module for acquiring the ambient temperature and the battery temperature;

[0043] a heating control module configured with a preheating strategy. The heating control module calculates the ambient heat dissipation efficiency, the heater efficiency, and the charging heat generation according to the preheating strategy to obtain a temperature correlation, and the temperature correlation reflects the relationship between the heater power, the charging power, and the battery charging temperature;

[0044] a charging performance evaluation module. The charging performance evaluation module is pre-trained with a charging performance evaluation model, obtains a target charging temperature based on the charging performance evaluation model, and outputs the target charging temperature to the heating control module so that the heater heats at a target power, and the target power conforms to the temperature correlation with the target charging temperature.

[0045] In the present invention, before formal charging, the battery is pre-heated to a certain temperature and then cooled, so that the environmental heat dissipation efficiency and the heater efficiency can be calculated. Then, by performing charging, the charging heat generation can be obtained. Thus, the temperature correlation can be obtained, that is, the relationship between the heater power, the charging power and the battery charging temperature. Then, by judging the correlation between the charging performance and the charging temperature when the battery is charging, the heater power is set so that the battery can be charged with the optimal charging performance.

[0046] In the present invention, preferably, the pre-heating strategy includes

[0047] successively obtaining a first temperature change curve, a second temperature change curve and a third temperature change curve. The first temperature curve is specifically a curve of the battery temperature changing with time during the process of heating the battery by controlling the heating module with a first heater power. The second temperature change curve is specifically a curve of the battery temperature changing with time during the cooling process after the heating module stops working. The third temperature change curve is specifically a curve of the battery temperature changing with time during the process of the charging module working and the heating module heating the battery by controlling the heating module with a second heater power;

[0048] calculating the environmental heat dissipation efficiency and the heater efficiency based on the first temperature change curve and the second temperature change curve;

[0049] calculating the charging heat generation based on the third temperature change curve.

[0050] Successively obtaining the first, second, and third temperature change curves, and calculating the environmental heat dissipation efficiency, the heater efficiency, and the charging heat generation based on these curves, realizing the quantification of the relationship between multiple key factors affecting the battery temperature, which helps the charger accurately master the relationship between the heater power, the charging power, and the battery charging temperature under different conditions, and can more precisely adjust the heating and charging parameters according to the actual environment and the characteristics of the battery itself, achieving the effect of improving the accuracy of the heating and charging processes, avoiding damage to the battery caused by improper heating or charging, and improving the battery charging efficiency and service life. Heat the battery once, then charge it, and then cool it to obtain the heat dissipation coefficient of the environment and the influence of the residual heat; when heating the battery for the second time, charge it and calculate the influence of the heat effect brought by charging, then the heat generation influence during charging can be estimated, and the charging power - heater power - battery temperature can be estimated to control the balance.

[0051] In the present invention, preferably, the charging performance evaluation module collects battery parameters at different battery temperatures. The battery parameters include charging efficiency, charging speed, battery internal resistance, and battery aging degree. The battery parameters are input into the charging performance evaluation model to obtain the charging performance score, and the charging performance scores at different battery temperatures are compared. The battery temperature with the highest charging performance score is used as the target charging temperature.

[0052] In the present invention, preferably, the calculation formula of the charging performance evaluation model is specifically

[0053] ;

[0054] where Q represents the charging performance score, η represents the charging efficiency, S represents the charging speed, R represents the internal resistance of the battery, and A represents the degree of battery aging.

[0055] To quantify the charging performance of the battery, multiple influencing factors need to be comprehensively considered. This formula takes into account the impacts of charging efficiency, charging speed, changes in battery internal resistance, and the degree of battery aging on charging performance:

[0056] η represents the charging efficiency: the ratio of the actual electricity charged into the battery to the electricity output by the charger, generally measured by an electricity metering device, with a value range of (0 - 1). For example, if the charger outputs 100 Wh of electricity and the battery actually charges 85 Wh, then the charging efficiency = 85% = 0.85.

[0057] The charging speed S is measured by the increase in battery power per unit time. Assuming the battery capacity is C (unit: Ah or mAh), and the time taken to charge from Q_1 to Q_2 is t (unit: hour h or minute min), then the charging speed S = (Q_2 - Q_1) / t. For example, if the battery capacity is 3000 mAh, and it takes 1 hour to charge from 20% (i.e., Q_1 = 3000 mAh × 0.2 = 600 mAh) to 80% (i.e., Q_2 = 3000 mAh × 0.8 = 2400 mAh), then the charging speed S = (2400 mAh - 600 mAh) / 1 h = 1800 mAh / h.

[0058] The internal resistance change rate R: The initial internal resistance of the battery is R_0, and after a certain number of charging cycles or usage time, the internal resistance becomes R_1. The internal resistance change rate R = (R_1 - R_0) / R_0. The internal resistance change rate reflects the change in the internal resistance of the battery with use. The greater the change in internal resistance, the greater the negative impact on charging performance.

[0059] The degree of battery aging A can be measured by the proportion of battery capacity decay. Assuming the initial battery capacity is C_0 and the current actual capacity is C_1, then the degree of battery aging A = 1 - (C_1) / (C_0). The higher the degree of aging, the worse the battery performance.

[0060] Formula explanation:

[0061] - The numerator part (η × S) represents the charging performance reflected by combining the charging efficiency and charging speed under ideal conditions. The higher the charging efficiency and the faster the charging speed, the larger this value.

[0062] - The denominator part ((1 + R) × (1 + A)) is used to correct the negative impact of internal resistance change and battery aging on charging performance. The greater the internal resistance change rate R and the battery aging degree A, the larger the denominator, and the smaller the overall CPI value, indicating the worse the charging performance.

[0063] In the present invention, preferably, the calculation formula for the environmental heat dissipation efficiency is as follows:

[0064] ;

[0065] Where represents the environmental heat dissipation efficiency, m represents the mass of the battery; c represents the specific heat capacity of the battery material; represents the decrease in battery temperature during the cooling process; represents the average temperature difference between the battery and the environment during the cooling process; represents the heat dissipation coefficient; A represents the surface area of contact between the battery and the environment; represents the cooling duration.

[0066] In the present invention, preferably, the calculation formula for the heater efficiency is as follows:

[0067] ;

[0068] Where represents the heater efficiency, represents the increase in battery temperature during the heating process; P represents the heater power; represents the heating duration.

[0069] In the present invention, preferably, the heating control module is configured with a temperature intervention strategy. When the change rate of the ambient temperature is greater than the preset temperature change rate, the heater power is adjusted based on the temperature intervention strategy. The temperature intervention strategy includes reducing the heater power, judging the change in battery temperature. If the battery temperature shows a decreasing trend, the heater power is gradually increased until the battery temperature is stable. If the battery temperature still shows an increasing trend, the heater power is gradually decreased until the battery temperature is stable, and the correlation between the environmental heat dissipation efficiency and the ambient temperature is recorded.

[0070] The following will be described in detail based on the order of the modules in combination with the circuit part.

[0071] I. Charging module, including a power conversion unit and a constant current and constant voltage control unit

[0072] 1. Power conversion unit

[0073] For the circuit diagram of the power conversion unit, please refer to Figure 2, The power conversion unit is used to convert the input alternating current ACL and ACN into direct current DC+ and DC- suitable for battery charging. Input side: The 220V alternating current is rectified by FU1 (6.3A) and BR1 (GBU1510), and filtered by CDO2 (400V / 150μF) to output about 300V direct current. Output connection: DC+ is directly connected to the U_control chip of the constant current control unit as the main charging power supply; GND is connected to the ground of all modules to form a common reference point.

[0074] Working process:

[0075] After being protected by FU1, the 220V alternating current enters BR1 for rectification and is converted into pulsating direct current;

[0076] CDO2 filters the pulsating direct current and outputs about 300V smooth direct current;

[0077] VDR1 plays an overvoltage protection role in the circuit. When the voltage is abnormal, it will clamp the excessive voltage to protect the backend circuit.

[0078] 2. Constant current and constant voltage control unit

[0079] Please refer to the constant current and constant voltage control unit Figure 4 , The voltage DC+ converted by the power conversion unit is regulated for constant voltage and constant current by the constant current and constant voltage control unit. One path forms a loop through QA1, RA1 and GND to charge the battery. Its core functions are: realizing constant current and constant voltage charging through the PWM regulation of the U_control chip, and the operational amplifier U3A and the resistor network (R22, R23, R24) form a feedback loop to monitor the output voltage / current in real time.

[0080] The constant current and constant voltage control unit is used to ensure the stability of current and voltage during the charging process and prevent overcharging or over-discharging of the battery. The core components include operational amplifiers U3A, U3B, feedback resistor network RO1~RO11 and PWM controller UTC81526E; it is linked with the power conversion unit through the feedback FB and current detection CS pins to adjust the output in real time. The constant current and constant voltage control unit receives the I_control and U_control signals from the MCU and dynamically sets the constant current / constant voltage threshold; it controls the switching frequency of the power conversion unit through UTC81526E to adjust the output voltage / current.

[0081] Output path:

[0082] Main charging loop: DC+ → QA1 (field effect transistor) → RA1 (current sampling resistor) → GND → battery BT1.

[0083] Power supply for the heating module: DC+ → DA1 (diode) → QA2 (PMOS transistor) → RL1-RL6 → GND.

[0084] Control association:

[0085] I_control signal (MCU pin 8): Dynamically adjusts the charging current (e.g., reduces the current when the temperature is too high).

[0086] SIF communication (PC2, R11, R16): Transmits the charging parameters (current, voltage) to the battery central control.

[0087] II. Heating module, including the battery heating unit

[0088] For the battery heating unit, please refer to Figure 3 , which is used to heat the battery in a low-temperature environment to ensure it operates within an appropriate temperature range. The voltage DC+ converted by the power conversion circuit is regulated for voltage and current by the constant current and constant voltage control unit, and another path forms a loop through DA1, QA2, and GND to heat the battery. Due to the limitation of the drawing size, Figure 2 and Figure 3 are not placed in the same drawing. In fact, FU2 in the upper right of the power conversion unit is connected to DA1 in the battery heating unit.

[0089] 1. Hardware execution part

[0090] Heating load: RL1-RL6 (6 47KΩ resistors in parallel, total power about 15W).

[0091] Control components:

[0092] QA2 (PMOS transistor): Controlled to conduct / turn off by the PWM signal output from MCU pin 12.

[0093] DA1 (diode): Prevents reverse current from damaging the heating circuit.

[0094] FU2 (heating fuse): Short-circuit protection.

[0095] 2. Control logic association

[0096] Temperature trigger:

[0097] RT1_in (MCU pin 9): Battery temperature signal (collected by NTC1A).

[0098] Preheating strategy: When the temperature < 20°C, the MCU drives QA2 to conduct through Q3 to start heating.

[0099] Temperature control logic:

[0100] The MCU collects the temperature signal of the battery pack through pin 9 (RT1_in).

[0101] When the temperature of the battery pack is lower than 20°C, the MCU's pin 12 outputs a high-level signal.

[0102] After the high-level signal is limited by R14, it drives Q3 (triode) to conduct.

[0103] After Q3 conducts, the gate of QA2 is pulled low, and the PMOS transistor QA2 conducts. The current passes through DA1, QA2, RL1 - RL6 and GND to form a loop, heating the battery.

[0104] When the temperature of the battery pack is higher than 20°C and lower than 60°C, the MCU's pin 12 outputs a low-level signal, Q3 cuts off, and QA2 turns off, stopping the heating.

[0105] Overheat protection function:

[0106] When the battery temperature exceeds 60°C, the charger will reduce the output current to avoid overheating of the battery.

[0107] When the battery temperature exceeds 70°C, the charger will cut off the charging circuit to prevent thermal runaway of the battery.

[0108] Heating efficiency calculation:

[0109] Based on the power of RL1 - RL6 (P = U² / R) and the heating duration (t), combined with the battery temperature rise ΔT, calculate the heater efficiency.

[0110] III. Temperature acquisition module

[0111] 1. Data acquisition points

[0112] Battery temperature: NTC1A (pin 9, RT1_in).

[0113] Charger temperature: NTC2 (assumed through pin 10, RT2_in).

[0114] Ambient temperature: Indirectly calculated through the cooling curve (the second temperature curve) (the MCU needs to record the cooling rate after heating stops).

[0115] 2. Data flow

[0116] ADC conversion: The temperature signal is converted into a digital quantity by the built-in ADC of the MCU.

[0117] Heating control module: The real-time temperature is used to judge the start and stop of heating (20°C threshold).

[0118] Charging performance evaluation module: The temperature data is used as an input parameter to calculate the charging efficiency (η), internal resistance (R), etc.

[0119] IV. Heating control module, including the core of the MCU control unit

[0120] For the MCU control unit, please refer to Figure 5 , the MCU control unit, as the core control module of the system, is responsible for receiving sensor signals such as temperature, current, voltage, logical judgment, and outputting control instructions. Specifically, it is connected to the temperature sensor (NTC) through pins RT1_in and RT2_in to monitor the battery temperature in real time; interacts with the constant current and constant voltage control unit through I_control and U_control signals to dynamically adjust the charging parameters; controls the battery heating unit, and triggers the SCR and the fan FAN1 through the heat signal to achieve temperature management.

[0121] The MCU control unit receives the feedback signals from the temperature sensor NTC1A and the current detection Isen, and outputs control signals to the constant current and constant voltage unit to adjust the charging parameters and to the heating unit to adjust the heating parameters.

[0122] 1. Algorithm implementation

[0123] Preheating strategy:

[0124] First temperature curve: When QA2 is turned on, record the temperature rise rate during the heating of RL1 - RL6.

[0125] Second temperature curve: When QA2 is turned off, record the natural cooling rate for calculating the environmental heat dissipation efficiency.

[0126] Third temperature curve: When charging and heating are carried out simultaneously, calculate the heat generated during charging, which needs to combine the charging current and the battery internal resistance.

[0127] Temperature intervention strategy:

[0128] When the environmental temperature change rate > threshold, dynamically adjust the PWM duty cycle of QA2 to maintain the target temperature.

[0129] 2. Interaction with other modules

[0130] Charging module: Adjust the charging current through the I_control signal (such as reducing the current when the temperature > 60°C).

[0131] Charging performance evaluation module: Receive the target temperature instruction and adjust the heating power.

[0132] SIF communication: Transmit the real-time temperature and heating status to the battery central control.

[0133] V. Charging performance evaluation module

[0134] The charging performance evaluation module does not have a dedicated hardware circuit and is implemented by the MCU through software.

[0135] 1. Data Input

[0136] Battery Parameters:

[0137] Charging efficiency (η) = actual charging capacity / theoretical capacity (to be calculated in combination with charging current and time).

[0138] Charging speed (S) = charging capacity / charging time.

[0139] Battery internal resistance (R) = voltage drop / charging current (sampled by RA1).

[0140] Battery aging degree (A) = historical charging cycle times (to be obtained from the battery central control via SIF communication).

[0141] 2. Model Output

[0142] Target temperature: Calculate the Q value at different temperatures and select the temperature with the maximum Q.

[0143] Instruction transmission: Send the target temperature to the heating control module to adjust the heating power.

[0144] Key data flow between modules:

[0145] 1) Temperature acquisition → heating control:

[0146] NTC1A → MCU pin 9 → preheating strategy calculation → QA2 conduction / cut-off.

[0147] 2) Charging performance evaluation → heating control:

[0148] Target temperature instruction → MCU pin 12 → PWM to adjust the duty cycle of QA2.

[0149] 3) Heating control → charging module:

[0150] High temperature signal (>60°C) → I_control → U_control to reduce the current.

[0151] 4) SIF communication:

[0152] Charging parameters (current, temperature) → PC2 → battery central control → display and feedback.

[0153] From the above working principle, it can be seen that: This charger can not only complete the automatic heating management of the battery, but also complete the battery charging management to avoid the battery from swelling; at the same time, it can also transmit information such as charging progress and battery temperature to the battery central control terminal to facilitate the display of charging information to the user. It effectively overcomes many problems mentioned in the background.

[0154] The above are only the preferred embodiments of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions falling within the concept of the present invention belong to the protection scope of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements should also be regarded as within the protection scope of the present invention.

Claims

1. A charger with a battery heating function, characterized in that: including a charging module configured to charge a battery; a heating module configured to heat the battery; a temperature acquisition module configured to acquire ambient temperature and battery temperature; a heating control module configured with a preheating strategy, the heating control module calculates ambient heat dissipation efficiency, heater efficiency, and charging heat generation according to the preheating strategy to obtain a temperature correlation, the temperature correlation reflects the relationship between heater power, charging power, and battery charging temperature; a charging performance evaluation module pre-trained with a charging performance evaluation model, obtains a target charging temperature based on the charging performance evaluation model, and outputs the target charging temperature to the heating control module to cause the heater to heat at a target power, the target power conforms to the temperature correlation with the target charging temperature; the charging performance evaluation module acquires battery parameters at different battery temperatures, the battery parameters include charging efficiency, charging speed, battery internal resistance, and battery aging degree, inputs the battery parameters into the charging performance evaluation model to obtain a charging performance score, compares the charging performance scores at different battery temperatures, and uses the battery temperature with the highest charging performance score as the target charging temperature; the calculation formula of the charging performance evaluation model is specifically ； Where Q represents the charging performance score, represents the charging efficiency, S represents the charging speed, R represents the internal resistance of the battery, and A represents the degree of battery aging.

2. The charger with a battery heating function according to claim 1, characterized in that: the preheating strategy includes successively obtaining a first temperature change curve, a second temperature change curve, and a third temperature change curve, the first temperature curve is specifically the curve of the battery temperature changing with time during the process of controlling the heating module to heat the battery with a first heater power, the second temperature change curve is specifically the curve of the battery temperature changing with time during the cooling process after the heating module stops working, the third temperature change curve is specifically the curve of the battery temperature changing with time during the process of the charging module working and the heating module controlling the heating module to heat the battery with a second heater power; calculating ambient heat dissipation efficiency and heater efficiency based on the first temperature change curve and the second temperature change curve; calculating charging heat generation based on the third temperature change curve.

3. The charger with a battery heating function according to claim 1, characterized in that: The calculation formula of the ambient heat dissipation efficiency is as follows: ; wherein represents the environmental heat dissipation efficiency, m represents the mass of the battery; c represents the specific heat capacity of the battery material; represents the decrease in the battery temperature during the cooling process; represents the average temperature difference between the battery and the environment during the cooling process; represents the heat dissipation coefficient; A represents the surface area of contact between the battery and the environment; represents the cooling duration.

4. The charger with a battery heating function according to claim 1, characterized in that: The calculation formula of the heater efficiency is as follows: ； where represents the heater efficiency, m represents the mass of the battery; c represents the specific heat capacity of the battery material; represents the increase in battery temperature during the heating process; P represents the heater power; represents the heating duration.

5. The charger with battery heating function according to claim 1, wherein: the heating control module is configured with a temperature intervention strategy, when the change rate of the ambient temperature is greater than a preset temperature change rate, the heater power is adjusted based on the temperature intervention strategy, the temperature intervention strategy includes reducing the heater power, judging the change of the battery temperature, if the battery temperature shows a decreasing trend, gradually increasing the heater power until the battery temperature is stable, if the battery temperature still shows an increasing trend, gradually decreasing the heater power until the battery temperature is stable, and recording the correlation between the ambient heat dissipation efficiency and the ambient temperature.

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