Comprehensive testing device integrating battery charging and electronic load
By optimizing the structure of the testing box and the definition of SOC, and combining it with the charging system and electronic load equipment, the problem of insufficient SOC estimation accuracy of lithium iron phosphate batteries has been solved, achieving more efficient battery utilization and safety testing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-31
- Publication Date
- 2026-03-27
AI Technical Summary
Existing SOC estimation methods for lithium iron phosphate batteries are insufficient in terms of accuracy and practicality, making it difficult to meet the needs of complex vehicle usage scenarios. They are also prone to overcharging and over-discharging, which reduces battery utilization.
This invention provides a comprehensive testing device that integrates battery charging and electronic load. By optimizing the test chamber structure and environmental control, and combining multiple experimental results, the definition of SOC is updated. A charging system and electronic load device are constructed to achieve balanced charging and accurate SOC assessment.
It significantly improves the accuracy of SOC estimation and battery utilization efficiency, ensures the stability and safety of the testing process, and meets practical application requirements.
Smart Images
Figure CN224052364U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to battery test technical field, concretely relates to integrated battery charging and electronic load's comprehensive testing device. BACKGROUND
[0002] Lithium iron phosphate battery (LiFePO4) is widely used in electric vehicles and energy storage systems due to its high safety, long cycle life and good thermal stability. The battery SOC (state of charge of the battery) is one of the most important and basic parameters in the power battery management system. Accurate estimation of battery SOC can control the charging and discharging process of the battery, avoid overcharging and overdischarging of the power battery, improve battery capacity, effectively utilize battery energy, prolong battery cycle life, and predict its driving range, optimize vehicle driving, and ensure the safety and long life of the battery during use.
[0003] In particular, since the discharge voltage platform of lithium iron phosphate power battery is high and flat, more energy can be released, but this also leads to no obvious change in voltage, making the SOC estimation method based on voltage have low accuracy, and it is difficult to accurately estimate the SOC of the battery in actual application. And in the actual use process of the power battery, due to the complex driving conditions of the electric vehicle, and the high nonlinearity of the power battery itself in use, it is greatly affected by temperature, current and other parameters, so it is more difficult to accurately estimate the battery SOC.
[0004] The SOC estimation method currently used such as open circuit voltage method (OCV) needs to rely on voltage measurement after the battery is at rest, and cannot estimate SOC in real time; the ampere-hour integration method needs to accurately measure and integrate the current, but is easily affected by sensor errors and cumulative errors; the model-based method such as Kalman filter can improve the estimation accuracy, but has strong dependence on model parameters and high computational complexity. Therefore, the estimation accuracy of SOC in the prior art is difficult to improve to meet the actual use requirements.
[0005] Therefore, in order to solve the problems that the existing lithium iron phosphate battery SOC estimation accuracy is not enough, it is difficult to meet the demand of complex vehicle use scenarios, overcharging, overdischarging and other phenomena are easy to occur, and the utilization rate of the battery is reduced, it is necessary to provide a comprehensive test device integrating battery charging and electronic load. INVENTION CONTENTS
[0006] The utility model intends to provide a comprehensive test device integrating battery charging and electronic load, so as to solve the problems that the existing lithium iron phosphate battery SOC estimation method has insufficient accuracy and practicability, is difficult to meet the demand of complex vehicle use scenarios, and cannot improve the battery utilization efficiency.
[0007] In order to achieve the above object, the utility model adopts the following technical scheme:
[0008] The utility model provides a kind of integrated battery charging and electronic load's comprehensive testing device, by optimizing device each test component and structure, and optimizing battery charging equipment and detection circuit structure, the optimization method of equipping setting is reduced battery interference factor in testing process, improve stability in testing process, to comprehensively improve the accuracy of battery SOC estimation.
[0009] The principle and advantages of the present scheme are:
[0010] The present scheme first constructs a new battery pack comprehensive detection device, adopts detection box to effectively shield the interference of external environment to battery pack, can also adjust temperature and environmental parameters in detection box in time according to the state of detection, to ensure accuracy and safety in detection process, to reduce the influence factor to battery pack, to ensure the effectiveness and accuracy of detection process from detection environment, to improve the precision of SOC evaluation.
[0011] Secondly, the present scheme updates the definition of SOC in combination with the results of multiple experiments and actual applications, to make it closer to the actual use of electric vehicle, on this basis, constructs charging system and electronic load equipment, and controls charging process reasonably according to actual running state, to make it can effectively and truly equalize charging according to the detected power of single battery, to ensure more effective equalization charging in detection process, to make each battery reach ideal state, to improve the accuracy of SOC evaluation, to meet actual use demand.
[0012] Further, the battery pack to be measured includes a plurality of single batteries connected in sequence by positive and negative electrodes; the parameter acquisition module includes a voltage collector and a temperature collector; the voltage collector is connected in parallel to the positive electrode of each single battery through a voltage acquisition line.
[0013] Further, the detection box comprises a box body, a connecting seat, a temperature sensing device and a humidity sensing device are arranged on a side wall of the box body, the temperature sensing device and the humidity sensing device are electrically connected with a temperature control device, a heating structure is arranged on the other side of the box body, the heating structure is electrically connected with the temperature control device, a ventilation and dehumidification structure is arranged on the box body, and the ventilation and dehumidification structure is electrically connected with the temperature control device.
[0014] Further, a wire detection module is arranged at the positive and negative electrode terminals of each single battery, the wire detection module comprises a resistor R1 connected to the negative electrode terminal of the first single battery, one end of a capacitor C1 and one end of a resistor R2 are connected in parallel on a control chip interface, the other end of the resistor R2 and the other end of the capacitor C1 are connected in parallel to the interface of the control chip, a vdd interface of the control chip is connected to the positive electrode terminal of the second single battery, and a vss interface of the control chip is connected to the negative electrode terminal of the second single battery.
[0015] Further, the charging machine comprises an equalization charging assembly, the equalization charging assembly comprises an energy dissipation type equalization unit and an energy non-dissipation type equalization unit, the energy dissipation type equalization unit comprises a switch control module and a shunt resistor module connected with the switch control module, and the energy non-dissipation type equalization unit comprises a DC-DC converter arranged in the charging machine.
[0016] Further, the heating structure comprises a heating assembly arranged in the side wall of the box body, a ventilation opening is arranged on the side wall of the box body, and an air inlet is arranged at the top end of the box body and is provided with a filter screen.
[0017] Further, the ventilation and dehumidification structure comprises a dehumidification module and a fan module, the dehumidification module is arranged at the air inlet, and the fan module is arranged at the ventilation opening.
[0018] Further, a control panel module is further arranged on the detection box and is electrically connected with the temperature control device.
[0019] Further, a damping pad is further arranged between the fan module and the box body, so that the vibration influence of the driving module in the box body is reduced, and the stability of the battery pack is ensured.
[0020] Further, the temperature sensing device comprises a plurality of temperature sensing devices arranged on the plurality of side walls of the detection box, so that the uniformity and comprehensiveness of temperature acquisition are ensured. BRIEF DESCRIPTION OF DRAWINGS
[0021] Figure 1 It is a structural schematic view of the utility model;
[0022] Figure 2 It is a structural schematic view of the detection box in the utility model;
[0023] Figure 3 It is the structure schematic view of the lead detection module in the utility model;
[0024] Figure 4 It is the structure schematic view of the balanced charging assembly in the utility model;
[0025] Figure 5 It is the structure schematic view of the switch control module in the utility model;
[0026] Figure 6 It is the structure schematic view of the energy non-dissipative balanced unit in the utility model;
[0027] Figure 7 It is the SOC state schematic view of the single battery when detecting in the utility model.
[0028] The mark in the drawing of the specification includes: detection box 1, box body 101, connecting seat 102, temperature sensing device 103, humidity sensing device 104, temperature control equipment 105, operation panel 106, heating structure 107, dehumidification module 108, fan module 109, ventilation opening 110, air inlet 111, box door 112;
[0029] Battery charging equipment 2, electronic load equipment 3, current collector 4, monitoring terminal 5;
[0030] To be measured battery group 6, parameter acquisition module 601. Specific implementation
[0031] The following is further explained in detail by specific implementation:
[0032] Example one
[0033] The embodiment is basically like the attached Figure 1As shown: integrated battery charging and electronic load comprehensive test device, through the optimization of battery charging equipment, the equalization charging of battery pack in different states can be realized, and the problem of battery inconsistency can be effectively avoided. At the same time, the judgment standard of SOC (State of Charge) is redefined, the test model of the monitoring terminal is optimized, and the corresponding test device is designed according to the model, so that the detection process is more in line with the actual demand. In addition, combined with various factors affecting the battery in the external environment (such as temperature, humidity, etc.), a detection box capable of reducing interference is set to ensure the accuracy of the test results and effectively improve the applicability and robustness of the test device. Specifically, the comprehensive test device includes a detection box 1 in a square structure, a battery charging device 2, an electronic load device 3, a current collector 4 and a monitoring terminal 5 connected with the detection box 1 through a cable. In this embodiment, the detection box 1 is used to place the battery pack 6 to be detected; the battery charging device 2 is used to control the charging of the battery pack 6 to be tested, the electronic load device 3 is used to simulate the actual load condition of the battery pack 6 to be tested, and the performance of the battery is tested and evaluated. The current collector 4 is a current sensor, such as an LT508-S6 type current sensor, which is used to collect the current state of the battery pack 6 to be tested during charging. The monitoring terminal 5 is an upper computer battery monitoring system, which can be realized by connecting a computer terminal operating device through a CAN bus to a USB module, which is used to obtain simulation data of the battery pack 6 to be tested and obtain detection data to display voltage, current, temperature and other information of the battery pack.
[0034] In this embodiment, as shown in the accompanying Figure 2 The detection box 1 includes a box body 101 in a square structure, the inner wall and the shell of the box body 101 are made of metal materials, such as copper, aluminum and other conductive materials, to form a shielding layer to avoid signal, static electricity and other interference. At the same time, it is ensured that the ground of the detection box and the equipment is good, so as to avoid the spread of electromagnetic interference through the ground wire. A box door 112 which can be opened and closed is arranged at the front of the box body 101, which is convenient for placing and taking the battery pack 6 to be tested, and can be closed after the battery pack 6 to be tested is placed and installed, to form a relatively closed test space and reduce the interference of the test environment. A temperature control device 105 is installed in the detection box 1, and an operation panel 106 is arranged at the top of the detection box 1, and the temperature control device 105 is electrically connected with the operation panel 106. A connecting seat 102 is arranged on one side wall of the detection box 1, which is used to connect the internal circuit with the battery pack 6 to be tested, and is connected with the battery charging device 2, the electronic load device 3 and the current collector 4 outside. In this embodiment, the electronic load device 3 can use the existing simulation test instrument, which will not be described in detail here.
[0035] A temperature sensing device 103 and a humidity sensing device 104 are also installed above the connecting seat 102, and the temperature sensing device 103 and the humidity sensing device 104 are respectively electrically connected with the temperature control equipment 105; so as to respectively obtain the temperature and humidity inside the detection box 1, and perform real-time feedback, so as to facilitate timely regulation of the internal environment through the temperature control equipment 105, and ensure the stability and effectiveness of the detection environment. Among them, the temperature sensing device 103 can adopt a temperature sensor, and the humidity sensing device can adopt a humidity sensor, so as to ensure the accuracy and timeliness of data monitoring. In the embodiment, the temperature sensing device 103 can be provided as a plurality of temperature sensing devices, which are respectively arranged on each side wall of the box body 101, so as to monitor the temperature distribution inside the box body 101 in real time, and ensure the comprehensiveness and coverage of the monitoring.
[0036] A heating structure 107 is installed on the other side of the box body 101, and the heating structure 107 is electrically connected with the temperature control equipment 105. In the embodiment, the heating structure 107 includes a heating assembly embedded in the side wall of the box body 101, which can be installed in the side wall of the box body 101 in the form of a heating film, a heating sheet or the like, so that the heating is more uniform, and the heating power density can be adjusted. When the external environment temperature is low, such as in winter or below 10℃ or below zero, the temperature control equipment 105 can be used to control the heating structure 107 to start, so that the environment inside the box body 101 can be quickly preheated to a suitable temperature, such as 20-35℃, and then the heating is turned off, and the battery pack 6 to be tested is placed in the detection box 1, so as to avoid the performance of the battery pack 6 to be tested being reduced in a low-temperature environment, and to affect the test accuracy of the battery. At the same time, in the embodiment, the entire device can be placed indoors during detection, and the indoor temperature can be adjusted as a whole, so as to avoid the external temperature being too low or too high, and affecting the overall performance.
[0037] A ventilation and dehumidification structure is also installed on the box body 101, and the ventilation and dehumidification structure is electrically connected with the temperature control equipment 105, and the start and stop of the ventilation and dehumidification structure is controlled by the temperature control equipment 105.
[0038] In this embodiment, the ventilation and dehumidification structure includes a dehumidification module 108 and a fan module 109. A ventilation opening 110 is formed on the lower part of the side wall of the box 101, and the fan module 109 is installed at the ventilation opening 110. The heat inside the box 101 is discharged outward by driving the fan module 109, so as to achieve the effect of heat dissipation and cooling. If the internal temperature is higher than 45℃, the internal temperature is lowered. A shock pad such as a rubber pad is arranged between the fan module 109 and the box 101 to reduce the vibration generated by the fan, motor and other equipment during operation, so as to avoid affecting the accuracy of the battery test. An air inlet 111 is formed at the top end of the box 101, and a filter screen is installed on the air inlet 111. The dehumidification module 108 is installed at the air inlet 111 and below the filter screen. When the fan module 109 is started, the external air will flow into through the air inlet 111. At this time, the flowing air will first pass through the dehumidification module 108 for dehumidification, so as to ensure the dryness of the entering air and the safety of the internal environment, and avoid affecting the effectiveness and accuracy of the battery test. In this embodiment, the dehumidification module 108 can be a sintered block, a honeycomb-shaped fixed structure made of a hygroscopic material such as molecular sieve and silica gel, so as to improve the hygroscopic effect. When the internal temperature is high during the detection process, the fan module 109 can be started by the temperature control device 105 to cool the internal temperature, so as to avoid the high temperature affecting the battery performance and thus affecting the accuracy of the test results.
[0039] An operation panel 106 is also installed on the detection box 1, and the operation panel 106 is electrically connected with the temperature control device 105. The internal temperature, humidity and other states can be viewed in real time through the operation panel 106, and the operation can be controlled in time, so as to ensure the stability and effectiveness of the internal detection environment, reduce the detection interference factors, and ensure the accuracy of the test.
[0040] A battery pack 6 to be tested is placed in the detection box 1. During the detection, the battery pack 6 to be tested is placed in the detection box 1 and electrically connected with the connecting seat 102 on the detection box 1, so as to make the battery pack 6 to be tested in communication with the external battery charging device 2, electronic load device 3, current collector 4 and monitoring terminal 5. In this embodiment, the battery pack 6 to be tested includes a plurality of single batteries connected in series with positive and negative electrodes. The number of single batteries is set to be 4-20, which can be adjusted according to the actual situation.
[0041] A parameter collection module 601 is connected to the battery pack 6 to be tested, and the parameter collection module 601 is connected with the monitoring terminal 5. In this embodiment, the parameter collection module 601 includes a voltage collector and a temperature collector, which are used to collect the voltage value and temperature value of each single battery in the battery pack 6 to be tested in real time. The voltage collector is connected in parallel with the positive electrode of each single battery through a voltage collection line.
[0042] A wire detection module 602 is arranged at the positive and negative terminals of each single battery, as shown in the accompanying drawings Figure 3 The wire detection module 602 includes a resistor R1 connected to the negative terminal of the first single battery, the other end of the resistor R1 is connected to the interface of the control chip, and the one end of a capacitor C1 and the one end of a resistor R2 are connected in parallel to the interface of the control chip. The other end of the resistor R2 and the other end of the capacitor C1 are connected in parallel to the interface of the control chip. The vdd interface of the control chip is connected to the positive terminal of the second single battery, and the vss interface of the control chip is connected to the negative terminal of the second single battery. The condition of the connecting wire of the battery pack is monitored in real time by the wire detection module 602, and the detection of the loose connection of the connecting wire between the batteries is realized by using two resistors and a capacitor, which avoids the increase of the contact resistance between the connecting wire and the battery terminal due to the loose connection of the connecting wire between the batteries, thereby causing the loss of battery energy, reducing the driving performance of the battery, and the loose terminal will generate a large amount of heat, which will affect the service life of the battery, and if the temperature is too high, it will cause the battery to explode or self-ignite, causing safety problems. Therefore, real-time detection of the connecting wire is realized, which can ensure the detection accuracy and test safety.
[0043] In this embodiment, the control chip can use a single-chip microcomputer with the model number MC9S08DZ16, the input signals of the two analog input channels are connected to the positive terminal of the battery (i+1) (i.e. the positive terminal of the second single battery) and the negative terminal of the adjacent battery (i) (i.e. the negative terminal of the first single battery), and the connecting wire connects the positive terminal of the battery (i+1) and the negative terminal of the adjacent battery (i). At this time, there is a voltage difference between the two analog input signals of the single-chip microcomputer, which includes the sum of the voltage between the positive terminal of the battery (i+1) and the connecting wire, the voltage on the connecting wire, and the voltage between the connecting wire and the negative terminal of the battery (i). The connection state of the connecting wire is determined by the voltage difference. Wherein, i takes the value of 1,..., N-1, and N is the number of single batteries connected in series in the battery pack. When the connecting wire is connected well, there is no potential difference between the negative terminal of the i-th battery and the positive terminal of the i+1-th battery, or the potential difference is very small even if there is current flowing through. The connection of the connecting wire can be detected by detecting the potential difference on the connecting wire.
[0044] When detection is needed, the interface pin of the single-chip microcomputer is set high, at this time no current flows through R1 and R2, so the detected voltage is 0, indicating that the connecting wire is connected well; on the contrary, if the detected voltage is not 0, it indicates that the connecting wire is loose. When the interface pin is set low, if the detected voltage is the same as the battery voltage, it indicates that the connecting wire is connected well, and if it is not the same as the battery voltage, it indicates that the connecting wire is loose.
[0045] After the placement and connection of the battery pack to be tested are completed, the battery charging device 2 is connected to the connecting seat 102 of the detection box 1 through a cable, so that the battery charging device 2 is in communication with the battery pack 6 to be tested. In the embodiment, the battery charging device 2 comprises a charging machine and a switch control module connected to the charging machine. The charging machine is connected to the detection box 1 through a cable, and the maximum output current of the charging machine can reach 100 A and the maximum output voltage can reach 60 V. The switch control module is electrically connected to the monitoring terminal 5, and the start and stop of the switch control module are controlled through the data fed back by the monitoring terminal 5.
[0046] As shown in the accompanying drawings, the charging machine comprises an equalization charging assembly, which comprises an energy dissipation type equalization unit and an energy non-dissipation type equalization unit. Figure 4 In the embodiment, the single battery is detected through the voltage collector and the temperature collector installed on the single battery, and the charging machine implements series charging on the battery pack. The energy dissipation type equalization unit comprises a switch control module and a shunt resistance module connected to the switch control module. The energy non-dissipation type equalization unit comprises a DC-DC converter arranged in the charging machine. The energy of the battery pack is transferred to the single battery for equalization charging during the charging control, so that the energy efficiency is improved.
[0047] In this embodiment, SOC is one of the most important parameters in the use of battery, which is used to describe the amount of remaining battery power. The current definition of SOC is from the perspective of power, that is, under certain discharge rate, the ratio of the remaining battery power to the rated capacity under the same conditions. And define the state of the battery when it is fully charged at a certain temperature as the full state of charge, that is, SOC = 1, and define the state of the battery when it is discharged to the cutoff condition as the empty state of charge, that is, SOC = 0. But in the actual use of electric vehicles, we find that due to the influence of self-discharge, aging, temperature, charge-discharge rate and other factors, the definition of SOC from the perspective of power is only applicable to constant current discharge state, not applicable to variable current discharge condition. However, in the actual operation of electric vehicles, it is impossible to discharge under certain fixed conditions, and in actual use and testing, it is also found that the battery discharge capacity changes with the change of parameters such as discharge termination voltage, environmental temperature, discharge current size and working mode, so before the end of discharge, since the discharge condition after that is unpredictable, when the battery external voltage reaches the discharge termination voltage, the discharge capacity of the battery is unknown. That is, when the battery is discharged to the cutoff voltage at a large current, the battery stops discharging, at this time, according to the traditional definition method, it is considered that SOC = 0, however, if it continues to discharge at a smaller current, it can still discharge a certain amount of power, which indicates that the actual battery has not finished discharging. If the existing SOC definition SOC is less than 0, it is not logical. That is, under high temperature, variable current or small current discharge conditions, the battery SOC may be less than 0; under large current, low temperature and other conditions, the battery SOC may be greater than 0 but cannot discharge power, resulting in differences between the test results of the battery pack and the actual use results, and the test is considered to be inaccurate and unreliable.
[0048] Therefore, the present scheme fully considers that in the actual work of electric vehicles, the power battery not only is in constant current charge-discharge state, but also is in variable current pulse charge-discharge state, redefines SOC to better adapt to variable current working condition. At the same time, combined with the setting of the equalization charging assembly, the charge-discharge process of the battery pack is more accurate and stable. Therefore, in this embodiment, SOC is defined as: at room temperature, the battery is charged according to the constant current-constant voltage charging method, and when the battery current drops to the specified current 0.03C (6A) in the constant voltage process, the battery is fully charged, SOC = 1; when the battery is discharged at a small current 0.05C (10A), when the battery voltage drops to the cutoff voltage (2.5V), the battery is discharged, SOC = 0. In this way, the discharge capacity of the battery from the full charge state to the discharged state is the relative maximum available capacity Q rmax of the battery; and the remaining power Q1 is defined as the discharge capacity of the battery from the current state to the discharged state. Therefore, the battery SOC is redefined as the ratio of the remaining power Q1 to the relative maximum available capacity Q rmax .
[0049]
[0050] In the formula, Q1 is the remaining battery charge at the calculation time; Q rmax Q represents the relative maximum usable capacity of the battery. d η is the amount of electricity discharged by the battery at the time of calculation; η is the coulombic efficiency of the battery, which is 1 in the new definition of SOC; i is the charging and discharging current, which is positive during discharging and negative during charging.
[0051] For battery packs used in series, to prevent overcharging or over-discharging of any individual cell, the State of Charge (SOC) of all individual cells must be between 0 and 1, and none of the individual cells should be under-voltage or over-voltage, thus ensuring the safety and long lifespan of the battery pack during use. Currently, to prevent individual cells from overcharging or over-discharging, the SOC of the cell with the lowest SOC in the battery pack is often used as the SOC of the battery pack. This solution also considers the available capacity of the corresponding individual cells to facilitate the estimation of variables such as the driving range and state of health of the electric vehicle.
[0052] In this embodiment, as shown in the appendix Figure 4 As shown, the equalization charging component includes multiple sets of single-cell battery charging components connected in series with the charger. Each set of single-cell battery charging components includes an energy dissipation type equalization unit and an energy non-dissipation type equalization unit connected to the positive and negative terminals of the single cell. The energy non-dissipation type equalization unit is connected to the single-cell detection unit, i.e., the parameter acquisition module 601, via a CAN bus. The single-cell detection unit is connected to the monitoring terminal 5 via a CAN bus.
[0053] In this embodiment, the energy dissipation balancing unit achieves balancing by discharging each battery cell in the battery pack through a power resistor (i.e., a shunt resistor module) connected in parallel. During charging, the switch control module can shunt the battery with the highest voltage during charging, as shown in the attached diagram. Figure 5 As shown, the switch control module includes n groups of individual battery control circuits connected in series with the charger. Taking the first group as an example, the individual battery control circuit includes a voltage detector 1 (i.e., a voltage acquisition unit) connected to the positive and negative terminals of the individual battery, and a resistor R1. Control switches are also connected to the positive and negative terminals of the individual battery, respectively.
[0054] In this embodiment, as shown in the appendix Figure 6As shown, the energy non-dissipative balancing unit includes a DC-DC converter housed within the charger. It can be configured as follows: a single-ended flyback circuit (isolated DC-DC converter), a high-frequency transformer, and an output filter connected sequentially to the battery pack voltage input. A single battery cell is connected to the output of the output filter, and one end of each battery cell is connected to a parameter acquisition module 601 and a monitoring terminal 5. A voltage and current sampling circuit and a balancing module control circuit are also connected to the output of the output filter. For example, a balancing module control circuit used in existing battery management systems (BMS) can be employed to achieve voltage / charge balancing of individual batteries within the battery pack. The other end of the balancing module control circuit is connected to the input of the single-ended flyback circuit. The output of the parameter acquisition module 601 is connected to the input of the single-ended flyback circuit.
[0055] In this embodiment, as shown in the appendix Figure 7 As shown, most batteries in a lithium iron phosphate power battery pack have a relatively consistent State of Charge (SOC). Only a few batteries have a higher or lower SOC due to self-discharge or other reasons. In this case, a uniform discharge method cannot be used because if the SOC is adjusted to be lower, the batteries with lower SOC will still have low charge. If there are many batteries with higher SOC, then more batteries will need to be equalized. Therefore, by combining the switching control module of the energy dissipation type equalization unit and the energy non-dissipation type equalization unit (the DC-DC converter uses the battery pack to equalize the individual cells), a low-charge, high-discharge equalization charging control strategy is adopted. That is, when the equalization charging condition is reached, the individual cells with particularly high SOC in the battery pack are discharged using a switch-controlled shunt resistor discharge method, while the individual cells with particularly low SOC in the battery pack are equalized using the DC-DC converter using the battery pack. This brings the SOC of the batteries at both ends closer to the middle, thereby ensuring the relative consistency of the overall battery pack SOC. This not only solves the problems of high energy consumption and low energy utilization in the resistance discharge equalization method, but also improves energy efficiency by using a DC-DC converter to recycle energy. It effectively solves the problem that equalization efficiency and energy utilization cannot be improved at the same time during the equalization charging process. In addition, this device has the characteristics of simple structure, low cost and high efficiency.
[0056] In this embodiment, a set of battery pack comprehensive detection device is creatively proposed, which significantly improves the accuracy and reliability of battery pack SOC (State of Charge) evaluation through technical breakthrough and system optimization. By designing a detection box, the interference of external environment on the battery pack can be effectively shielded. The detection box is equipped with intelligent temperature control and environment regulation system, which can adjust the internal temperature and environment parameters in real time according to the detection requirements, ensuring that the detection process is carried out under optimal conditions. This design not only significantly reduces the interference of external factors on the detection results, but also guarantees the accuracy and safety of data collection from the detection environment level, providing a reliable hardware foundation for SOC evaluation. Through environmental control and intelligent adjustment, the detection error is minimized, making it more close to the actual demand.
[0057] At the same time, in this embodiment, based on a large amount of experimental data and analysis of actual application scenarios, the definition of SOC is innovatively optimized to make it more suitable for the real use of electric vehicles. On this basis, an intelligent charging system and electronic load equipment are developed to realize precise control of the charging process. The system can dynamically adjust the charging strategy according to the state of charge of single battery, realizing true balanced charging. It ensures that each single battery of the battery pack reaches the ideal state during the detection process, thereby significantly improving the accuracy and consistency of SOC evaluation.
[0058] The above is only an embodiment of the present application, and the well-known specific technical solutions and / or characteristics in the scheme are not described in detail. It should be noted that for those skilled in the art, without departing from the technical solutions of the present application, some modifications and improvements can be made, which should also be considered as the protection scope of the present application. These will not affect the effect and practicality of the present application. The protection scope of the present application should be subject to the content of its claims, and the specific implementation mode and the like in the specification can be used to explain the content of the claims.
Claims
1. An integrated battery charging and electronic load combined test device, characterized by: The application relates to a battery testing device, which comprises a testing box, a battery charging device, an electronic load device, a current collector and a monitoring terminal connected with the testing box through a cable; the battery charging device comprises a charging machine and a switch control module connected with the charging machine; the charging machine is connected with the testing box; the switch control module is connected with the monitoring terminal; a battery group to be tested is placed in the testing box; the battery group to be tested is electrically connected with the testing box; a parameter collection module is arranged on the battery group to be tested and connected with the monitoring terminal; a temperature control device is arranged in the testing box.
2. The integrated battery charge and electronic load combination test device of claim 1, wherein: The battery group to be tested comprises a plurality of single batteries connected in sequence at positive and negative poles; the parameter collection module comprises a voltage collector and a temperature collector; the voltage collector is connected in parallel with the positive poles of the single batteries through a voltage collection line.
3. The integrated battery charge and electronic load combination test device of claim 1, wherein: The testing box comprises a box body, a connecting seat, a temperature sensing device and a humidity sensing device arranged on one side wall of the box body; the temperature sensing device and the humidity sensing device are electrically connected with a temperature control device; a heating structure is arranged on the other side of the box body and electrically connected with the temperature control device; a ventilation and dehumidification structure is arranged on the box body and electrically connected with the temperature control device.
4. The integrated battery charge and electronic load combination test device of claim 2, wherein: A wire detection module is arranged at the positive and negative poles of each single battery; the wire detection module comprises a resistor R1 connected to the negative pole of a first single battery, one end of a capacitor C1 and one end of a resistor R2 connected in parallel on a control chip interface; the other end of the resistor R2 and the other end of the capacitor C1 are connected in parallel to the interface of the control chip; a vdd interface of the control chip is connected to the positive pole of a second single battery, and a vss interface of the control chip is connected to the negative pole of the second single battery.
5. The integrated battery charge and electronic load combination test device of claim 1, wherein: The charging machine comprises an equalization charging assembly, the equalization charging assembly comprises an energy dissipation type equalization unit and an energy non-dissipation type equalization unit; the energy dissipation type equalization unit comprises a switch control module and a shunt resistor module connected with the switch control module; the energy non-dissipation type equalization unit comprises a DC-DC converter arranged in the charging machine.
6. The integrated battery charge and electronic load combination test device of claim 3, wherein: The heating structure comprises a heating assembly arranged in the side wall of the box body; a ventilation opening is arranged on the side wall of the box body; an air inlet is arranged at the top end of the box body and provided with a filter screen.
7. The integrated battery charge and electronic load combination test device of claim 6, wherein: The ventilation and dehumidification structure comprises a dehumidification module and a fan module; the dehumidification module is arranged at the air inlet, and the fan module is arranged at the ventilation opening.
8. The integrated battery charge and electronic load combination test device of claim 1, wherein: A control panel module is further arranged on the testing box and electrically connected with the temperature control device.
9. The integrated battery charge and electronic load combination test device of claim 7, wherein: A shock-absorbing pad is further arranged between the fan module and the box body.
10. The integrated battery charge and electronic load combination test device of claim 3, wherein: The temperature sensing device comprises a plurality of temperature sensing devices arranged on the side walls of the testing box.