Output control optimization method and system for high-temperature DC charging current of power battery

Abstract

The present application discloses an output control optimization method and system for high-temperature DC charging current of a power battery, the method comprising the following steps: obtaining the current temperature of the power battery; comparing the current temperature of the power battery with a high-temperature threshold to obtain a comparison condition; when the high-temperature threshold is exceeded, obtaining the temperature difference between the power battery temperature and the ambient temperature; obtaining the current output suppression optimization coefficient corresponding to the current temperature difference interval according to the obtained temperature difference value; obtaining the optimized charging current value according to the obtained current output suppression optimization coefficient corresponding to the current temperature difference interval; controlling the output of the obtained optimized charging current value to charge the power battery. The present application suppresses the temperature rise of the battery by matching the current output suppression optimization coefficient according to the temperature difference value when the temperature of the power battery exceeds a certain temperature, avoiding the battery from prematurely entering the high-temperature condition current output sudden drop charging mode, effectively shortening the time required for charging the power battery and improving the charging efficiency of the power battery.

Description

Technical Field

[0001] The present application relates to the technical field of power batteries, and specifically to an output control optimization method and system for high-temperature direct current charging current of a power battery. Background Art

[0002] At present, electric vehicles are developing rapidly in my country, with production and sales increasing significantly, and the requirements for electric vehicle operating efficiency are getting higher and higher. Among them, the slow charging speed at high temperature is a problem of general concern, especially for power batteries with natural air cooling. The problem of slow charging at high temperature is particularly prominent. The charging current of power batteries generally requests the current maximum charging current from the ground charging pile according to the preset battery DC charging matrix table (the maximum continuous charging current corresponding to different temperatures, different SOCs or voltages). However, when the ambient temperature and power battery temperature are high, if the charging current is too large, the battery cell temperature will further rise, and the higher the battery temperature, the smaller the corresponding allowable charging current, which directly leads to longer charging time. In particular, after the power battery temperature reaches 50°C, the allowable charging current of the battery decreases sharply, and the charging time is too long, resulting in a very poor charging experience. Summary of the invention

[0003] The purpose of this application is to overcome the deficiencies of the above-mentioned background technology and to provide a method and system for optimizing the output control of high-temperature DC charging current of a power battery.

[0004] In a first aspect, a method for optimizing output control of a high-temperature DC charging current of a power battery is provided, comprising the following steps:

[0005] Get the current temperature of the power battery;

[0006] Compare the current temperature of the power battery with the high temperature threshold to obtain the comparison working condition;

[0007] When the current temperature of the power battery exceeds the high temperature threshold, the temperature difference between the power battery temperature and the ambient temperature is obtained;

[0008] According to the obtained temperature difference value, obtain the current output suppression optimization coefficient corresponding to the current temperature difference interval, and the current output suppression optimization coefficient is not greater than 1;

[0009] Obtain an optimized charging current value according to the current output suppression optimization coefficient corresponding to the current temperature difference range;

[0010] The optimized charging current value obtained by the control output is used to charge the power battery.

[0011] According to the first aspect, in a first implementation of the first aspect, after the step of comparing the current temperature of the power battery with the high temperature threshold and obtaining the comparison operating condition, the following steps are also included:

[0012] When the current temperature of the power battery does not exceed the high temperature threshold, the control outputs the charging current according to the preset battery DC charging matrix table.

[0013] According to the first aspect, in a second implementation of the first aspect, before the step of obtaining the current temperature of the power battery, the following steps are also included:

[0014] When the electric vehicle obtains a charging wake-up signal, the DC charging condition of the charging pile is obtained to meet the working condition;

[0015] When the charging pile meets the DC charging conditions, the electric vehicle and the charging pile are controlled to handshake to exchange information.

[0016] According to the first aspect, in a third implementation method of the first aspect, the current output suppression optimization coefficient corresponding to the current temperature difference interval is obtained based on the obtained temperature difference value, and the current output suppression optimization coefficient is not greater than 1. In the step, the larger the temperature difference value is, the smaller the current output suppression optimization coefficient corresponding to the current temperature difference interval is.

[0017] According to the third implementation of the first aspect, in the fourth implementation of the first aspect, the step of obtaining the current output suppression optimization coefficient corresponding to the current temperature difference interval according to the obtained temperature difference value, wherein the current output suppression optimization coefficient is not greater than 1, specifically includes the following steps:

[0018] When the temperature difference value is lower than the first temperature difference threshold, the current output suppression optimization coefficient corresponding to the current temperature difference interval is the first current output suppression optimization coefficient; and / or,

[0019] When the temperature difference value is between the first temperature difference threshold and the second temperature difference threshold, the current output suppression optimization coefficient corresponding to the current temperature difference interval is the second current output suppression optimization coefficient; and / or,

[0020] When the temperature difference value is between the second temperature difference threshold and the third temperature difference threshold, the current output suppression optimization coefficient corresponding to the current temperature difference interval is the third current output suppression optimization coefficient; and / or,

[0021] When the temperature difference value is greater than the third temperature difference threshold, the current output suppression optimization coefficient corresponding to the current temperature difference interval is the fourth current output suppression optimization coefficient;

[0022] Wherein, the first temperature difference threshold value < the second temperature difference threshold value < the third temperature difference threshold value < the fourth temperature difference threshold value;

[0023] 0≤fourth current output suppression optimization coefficient<third current output suppression optimization coefficient<second current output suppression optimization coefficient<first current output suppression optimization coefficient≤1.

[0024] According to the fourth implementation manner of the first aspect, in the fifth implementation manner of the first aspect, the first temperature difference threshold, the second temperature difference threshold and the third temperature difference threshold are calibrated and obtained according to the heat generation and heat exchange amount of the power battery.

[0025] According to the first aspect, in a sixth implementation of the first aspect, the step of obtaining the optimized charging current value according to the current output suppression optimization coefficient corresponding to the current temperature difference interval obtained specifically includes the following steps:

[0026] Obtaining a first maximum continuous charging current value allowed by the power battery system corresponding to the current temperature of the power battery;

[0027] Obtaining the second highest continuous charging current value allowed by the power battery system corresponding to the preset temperature rise of the current temperature of the power battery;

[0028] An optimized charging current value is obtained according to the obtained first highest continuous charging current value, the second highest continuous charging current value, and the current output suppression optimization coefficient.

[0029] In a second aspect, the present application provides an output control optimization system for a power battery high temperature DC charging current, comprising:

[0030] The current temperature acquisition module is used to obtain the current temperature of the power battery;

[0031] A comparison operating condition acquisition module, which is in communication with the current temperature acquisition module and is used to compare the current temperature of the power battery with the high temperature threshold to acquire a comparison operating condition;

[0032] A temperature difference value acquisition module is connected in communication with the comparison working condition acquisition module, and is used to obtain the temperature difference value between the power battery temperature and the ambient temperature when the current temperature of the power battery exceeds the high temperature threshold;

[0033] A current output suppression optimization coefficient acquisition module is connected to the temperature difference value acquisition module for acquiring a current output suppression optimization coefficient corresponding to a current temperature difference interval according to the acquired temperature difference value, wherein the current output suppression optimization coefficient is not greater than 1;

[0034] An optimized current acquisition module is connected to the current output suppression optimization coefficient acquisition module for obtaining an optimized charging current value according to the obtained current output suppression optimization coefficient corresponding to the current temperature difference interval;

[0035] The first current output control module is in communication with the optimized current acquisition module and is used to control the output of the acquired optimized charging current value to charge the power battery.

[0036] According to the second aspect, in a first implementation of the second aspect, it further includes:

[0037] The second current output control module is communicatively connected with the comparison working condition acquisition module, and is used for controlling the output of the charging current according to the preset battery DC charging matrix table when the current temperature of the power battery does not exceed the high temperature threshold.

[0038] According to the second aspect, in a second implementation of the second aspect, it further includes:

[0039] A condition-satisfying working condition acquisition module is used to obtain the DC charging condition of the charging pile when the electric vehicle obtains a charging wake-up signal;

[0040] The handshake module is communicatively connected with the condition-satisfying working condition acquisition module, and is used to control the electric vehicle and the charging pile to handshake and exchange information when the charging pile meets the DC charging conditions.

[0041] Compared with the prior art, the advantages of this application are as follows:

[0042] The output control optimization method of high-temperature DC charging current of a power battery provided in the present application matches the current output suppression optimization coefficient according to the temperature difference between the battery temperature and the ambient temperature when the temperature of the power battery exceeds a certain temperature, thereby suppressing the temperature rise of the battery and preventing the battery from entering the high-temperature operating condition current output sudden drop charging mode too early, effectively shortening the time required for power battery charging and improving the charging efficiency of the power battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 A method flow chart of a method for optimizing output control of a high-temperature DC charging current of a power battery provided in an embodiment of the present application;

[0044] Figure 2 Another method flow chart of the method for optimizing the output control of high-temperature DC charging current of a power battery provided in an embodiment of the present application;

[0045] Figure 3 A functional module block diagram of a power battery high temperature DC charging current output control optimization system provided in an embodiment of the present application;

[0046] Figure 4 This is another functional module block diagram of the output control optimization system for high-temperature DC charging current of a power battery provided in an embodiment of the present application. DETAILED DESCRIPTION

[0047] The specific embodiments of the present application will now be described in detail, examples of which are illustrated in the accompanying drawings. Although the present application will be described in conjunction with the specific embodiments, it will be understood that it is not intended to limit the present application to the described embodiments. On the contrary, it is intended to cover the changes, modifications and equivalents included in the spirit and scope of the present application as defined by the appended claims. It should be noted that the method steps described herein can be implemented by any functional block or functional arrangement, and any functional block or functional arrangement can be implemented as a physical entity or a logical entity, or a combination of the two.

[0048] In order to enable those skilled in the art to better understand the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0049] Note: The example to be introduced below is only a specific example, and is not intended to limit the embodiments of the present application to the following specific steps, values, conditions, data, sequences, etc. Those skilled in the art can apply the concept of the present application to construct more embodiments not mentioned in the present description by reading the present description.

[0050] In the prior art, when the power battery charging reaches a certain high temperature value, the high temperature current limiting charging mode is entered due to the high temperature of the power battery. The existing high temperature current limiting charging mode is a single gradient current drop output control. The charging current allowed by the power battery drops sharply, resulting in a slow charging process of the power battery and a long charging time, which affects the charging experience.

[0051] The main source of heat for power battery charging is the large current charging the battery, and the battery will also exchange heat with the outside, which can be passive heat dissipation of the power battery natural air cooling, or active liquid cooling, direct cooling, etc., thus obtaining formula (1):

[0052] Q 堆积 =Q 充电 -Q 交换 Formula (1)

[0053] Among them, Q 堆积 is the heat accumulated inside the battery, Q 充电 To charge the battery, the heat released by the battery itself, Q 交换 The heat exchanged between the battery and the outside world.

[0054] From the thermal formula Q = c × m × △ t, we can know that for a power battery in charging, Q 堆积 The smaller the Q, the smaller the temperature rise of the battery. 堆积 , which can reduce the charging current and thus reduce Q 充电 , it can also increase the heat exchange Q between the battery and the outside 交换 .

[0055] This application mainly reduces Q 充电 Reduce the heat accumulated inside the battery, gradually increase the suppression amplitude or reduction amplitude of the charging current to reduce the heat accumulated inside the battery, optimize the control strategy of the charging current, avoid directly entering the current output control mode with a sharp drop, and affect the charging efficiency of the power battery.

[0056] See also Figure 1 As shown, the embodiment of the present application provides a method for optimizing output control of a high-temperature DC charging current of a power battery, comprising the following steps:

[0057] Step S1, obtaining the current temperature of the power battery;

[0058] Step S2, comparing the current temperature of the power battery with the high temperature threshold to obtain a comparison operating condition;

[0059] Step S31: When the current temperature of the power battery exceeds the high temperature threshold, the temperature difference between the power battery temperature and the ambient temperature is obtained by the battery system in real time as follows:

[0060] m=T max -T0;

[0061] In the formula, negative values ​​of temperature difference are valid;

[0062] Step S41, obtaining a current output suppression optimization coefficient corresponding to the current temperature difference interval according to the obtained temperature difference value, wherein the current output suppression optimization coefficient is not greater than 1;

[0063] Step S51, obtaining an optimized charging current value according to the current output suppression optimization coefficient corresponding to the current temperature difference interval;

[0064] Step S61, controlling the output to obtain the optimized charging current value to charge the power battery.

[0065] In the present application, the current temperature of the power battery refers to the current maximum temperature of the power battery, so as to accurately delay the time when the power battery enters a high degree of current output suppression, that is, a DC charging mode with a sudden drop in current output.

[0066] The present application provides an output control optimization method for high-temperature DC charging current of a power battery. When the temperature of the power battery exceeds a certain temperature, the current output suppression optimization coefficient is matched according to the temperature difference between the battery temperature and the ambient temperature to suppress the current output, avoid excessive temperature rise of the power battery, enter a high-temperature and significantly reduced current charging mode, effectively shorten the time required for power battery charging, and improve the charging efficiency of the power battery.

[0067] In one embodiment, since the maximum allowable charging current of a power battery is generally between 25°C and 40°C, after the battery temperature exceeds 40°C, as the temperature rises, the allowable charging current of the battery will decrease accordingly, especially after the power battery temperature reaches 50°C, the allowable charging current of the battery decreases sharply, see Table 1 Battery DC Charging Matrix. When the battery temperature is below 35°C, the power battery is charged according to the charging current requested by the preset battery DC charging matrix. In this application, the high temperature threshold is set to 35°C, mainly for charging strategies with battery temperatures above 35°C (inclusive), to suppress the temperature rise of the power battery and shorten the time required for charging. In other embodiments of the present application, the temperature difference threshold is set differently according to the quality of the battery cell to suit different battery systems.

[0068] In one embodiment, please refer to Figure 2 , a current output control strategy is provided for the power battery temperature ultra-high temperature working condition and the power battery temperature is not ultra-high temperature working condition. The embodiment of the present application provides an output control optimization method for a power battery high temperature DC charging current, comprising the following steps:

[0069] Step S1, obtaining the current temperature of the power battery;

[0070] Step S2, comparing the current temperature of the power battery with the high temperature threshold to obtain a comparison operating condition;

[0071] Step S31: when the current temperature of the power battery exceeds the high temperature threshold, obtaining the temperature difference between the power battery temperature and the ambient temperature;

[0072] Step S41, obtaining a current output suppression optimization coefficient corresponding to the current temperature difference interval according to the obtained temperature difference value, wherein the current output suppression optimization coefficient is not greater than 1 and not less than 0;

[0073] Step S51, obtaining an optimized charging current value according to the current output suppression optimization coefficient corresponding to the current temperature difference interval;

[0074] Step S61, controlling the output to obtain the optimized charging current value to charge the power battery;

[0075] Step S32: When the current temperature of the power battery exceeds the high temperature threshold, the charging current is output according to the preset battery DC charging matrix table, wherein the preset charging current DC charging matrix table ((the maximum continuous charging current corresponding to different temperatures, different SOCs or voltages) is shown in Table 1:

[0076] Table 1 Battery DC charging matrix (unit: rate C)

[0077] S0C 0％ 10％ 20％ 30％ 40％ 50％ 60％ 70％ 80％ 90％ 100％ Tmin<0℃ 0 0 0 0 0 0 0 0 0 0 0 Tmin 0℃ 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Tmin 5℃ 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.15 0.15 0.15 Tmin 10℃ 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.2 0.2 0.2 Tmin 15℃ 0.5 0.5 0.7 0.7 0.7 0.7 0.7 0.7 0.5 0.5 0.3 Tmax 20℃ 0.86 0.86 0.86 0.86 0.86 0.86 0.86 0.86 0.86 0.7 0.5 Tmax 25℃ 1 1 1 1 1 1 1 1 1 1 0.7 Tmax 35℃ 1 1 1 1 1 1 1 1 1 1 0.7 Tmax 40℃ 1 1 1 1 1 1 1 1 1 1 0.7 Tmax 45℃ 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.3 0.3 Tmax 50℃ 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.2 0.2 Tmax 55℃ 0.1 0.1 0.2 0.2 0.2 0.2 0.2 0.2 0.1 0.1 0.1 Tmax 60℃ 0 0 0 0 0 0 0 0 0 0 0

[0078] The control optimization method of the DC charging current of a power battery provided in the present application provides a current output suppression control strategy when the temperature of the power battery is too high, so as to prevent the power battery from prematurely entering a high-temperature current limiting charging mode in which the current output suddenly drops, thereby affecting the charging efficiency; when the temperature of the power battery is not too high, the output is performed according to a predetermined output strategy, thereby effectively ensuring the smooth progress of the power battery charging procedure, while ensuring the charging efficiency of the power battery.

[0079] In one embodiment, a complete current output control strategy is provided for a charging vehicle, and before the step of obtaining the current temperature of the power battery, the following steps are also included:

[0080] After the DC charging pile is connected to the electric vehicle plug, the charging pile outputs an A+ signal to the electric vehicle, which is a charging wake-up signal;

[0081] When the electric vehicle obtains the charging wake-up signal, the electric vehicle detects and obtains that the DC charging condition of the charging pile meets the working condition;

[0082] When the charging pile meets the DC charging conditions, the electric vehicle and the charging pile are controlled to handshake and exchange information, and the electric vehicle sends a charging ready message to the charging pile;

[0083] The charging pile obtains the charging readiness message, and when ready, the charging pile feeds back the charging readiness to the electric vehicle;

[0084] At this point, the pre-charging preparations are completed, and the DC charging operation for the power battery of the electric vehicle is performed.

[0085] In one embodiment, according to the obtained temperature difference value, the current output suppression optimization coefficient corresponding to the temperature difference interval in which the current temperature difference value is located is obtained, and the current output suppression optimization coefficient is not greater than 1. In the step, the larger the temperature difference value is, the smaller the current output suppression optimization coefficient corresponding to the current temperature difference interval is.

[0086] The control optimization method of the DC charging current of a power battery provided in the present application has a higher degree of suppression of the current output control when the temperature difference between the power battery and the ambient temperature is larger, thereby realizing a gradual current output suppression control strategy under high temperature conditions, and effectively avoiding the premature and high-amplitude output suppression control of the charging current under high temperature conditions, which affects the charging time required to fully charge the power battery, and affects the charging experience of the electric vehicle and the operating efficiency of the electric vehicle.

[0087] In one embodiment, the step of obtaining the current output suppression optimization coefficient corresponding to the current temperature difference interval according to the obtained temperature difference value, wherein the current output suppression optimization coefficient is not greater than 1, specifically includes the following steps:

[0088] A. When the temperature difference value is lower than the first temperature difference threshold, the current output suppression optimization coefficient corresponding to the current temperature difference interval is the first current output suppression optimization coefficient; and / or,

[0089] B. When the temperature difference value is between the first temperature difference threshold and the second temperature difference threshold, the current output suppression optimization coefficient corresponding to the current temperature difference interval is the second current output suppression optimization coefficient; and / or,

[0090] C. When the temperature difference value is between the second temperature difference threshold and the third temperature difference threshold, the current output suppression optimization coefficient corresponding to the current temperature difference interval is the third current output suppression optimization coefficient; and / or,

[0091] D. When the temperature difference value is greater than the third temperature difference threshold, the current output suppression optimization coefficient corresponding to the current temperature difference interval is the fourth current output suppression optimization coefficient;

[0092] Among them, the first temperature difference threshold value < the second temperature difference threshold value < the third temperature difference threshold value < the fourth temperature difference threshold value, 0≤the fourth current output suppression optimization coefficient < the third current output suppression optimization coefficient < the second current output suppression optimization coefficient < the first current output suppression optimization coefficient≤1.

[0093] The control optimization method of the power battery DC charging current provided in the present application realizes that the temperature difference threshold is increased, and the higher the current output control suppression amplitude is, the current output suppression degree is gradually increased to perform current output control, and compared with the prior art in which the output current drops sharply when the power current is charged under high temperature conditions, the time required to fully charge the power battery is effectively shortened, thereby improving the charging experience of the power battery and the operating efficiency of the electric vehicle.

[0094] In a more specific embodiment, the temperature difference is recorded as m, and the current output suppression optimization coefficient is recorded as k. After calibration verification, the m value is divided into 4 intervals to define different k values, which can effectively shorten the charging time of the power battery under high temperature conditions. The current output suppression optimization coefficient corresponding to the current temperature difference interval is obtained according to the obtained temperature difference value, and the current output suppression optimization coefficient is not greater than 1. The steps specifically include the following steps:

[0095] When m<-3℃, k is 1;

[0096] When -3℃≤m<0℃, k is 0.8;

[0097] When 0℃≤m<3℃, k is 0.5;

[0098] When m≥3℃, k is 0.

[0099] It should be noted that different battery systems have different heat generation Qcharging and heat exchange Qexchange with the outside world. The partition interval of the temperature difference m and its corresponding k value in this application are not suitable for all battery systems. It is necessary to calibrate and verify the high-temperature charging of the battery system, and then take the appropriate k value for different difference m to calculate the charging current I c , in order to suppress the battery charging temperature rise and shorten the charging time.

[0100] In one embodiment, the step of obtaining the optimized charging current value according to the current output suppression optimization coefficient corresponding to the current temperature difference interval obtained specifically includes the following steps:

[0101] Obtaining a first maximum continuous charging current value allowed by the power battery system corresponding to the current temperature of the power battery;

[0102] Obtaining the second highest continuous charging current value allowed by the power battery system corresponding to the preset temperature rise of the current temperature of the power battery;

[0103] The first highest continuous charging current value, the second highest continuous charging current value and the current output suppression optimization coefficient are numerically transformed according to the following formula to obtain the optimized charging current value I c :

[0104] I c =I t+n +k×(I t -I t+n )

[0105] In the formula, I c is the charging current value requested by the BMS, I t I is the maximum continuous charging current value allowed by the BMS when the temperature is t. t+n is the maximum continuous charging current value allowed by the BMS when the temperature is t+n℃, n is the increase in current suppression output required for battery temperature rise, more specifically, n is 5. In other embodiments of the present application, n can be set to other values ​​according to the quality of the battery cell. For example, the better the high temperature resistance of the battery cell, the larger the value of n, conversely, the worse the high temperature resistance of the battery cell, the smaller the value of n.

[0106] Among them, the k value is a calibration value, 0≤k<1. Different battery systems have different heat generation during charging and heat exchange with the outside world. In order to shorten the charging time as much as possible, it is necessary to perform targeted calibration and verification of the k values ​​of different battery systems to suppress the temperature rise of the battery and avoid the battery entering the high-temperature and large-current reduction charging mode too early.

[0107] The control optimization method of the power battery DC charging current provided in the present application is based on the temperature difference between the power battery temperature and the ambient temperature, and performs gradual output suppression control on the basis of a predetermined current output amplitude to prevent the power battery from directly entering a high-temperature current output control program, thereby effectively shortening the power battery charging time and improving the charging experience of the charging vehicle.

[0108] The output control optimization method of high-temperature DC charging current of a power battery provided in the present application is not only applicable to the charging current output control of the power battery in an electric vehicle, but can also be separately applied to the charging current output control of high-temperature charging of various power lithium-ion batteries and other power batteries, thereby avoiding charging of the power battery under high-temperature conditions, prematurely entering a charging state where the charging current is highly suppressed under high-temperature conditions, and affecting the charging efficiency of the power battery.

[0109] Based on the same invention concept, please refer to Figure 3 The output control optimization system of high-temperature DC charging current of a power battery provided in the present application includes a current temperature acquisition module 100, a comparison condition acquisition module 200, a temperature difference acquisition module 310, a current output suppression optimization coefficient acquisition module 410, an optimized current acquisition module 510 and a first current output control module 610. The current temperature acquisition module 100 is used to acquire the current temperature of the power battery; the comparison condition acquisition module 200 is connected in communication with the current temperature acquisition module 100 and is used to compare the current temperature of the power battery with a high temperature threshold and acquire the comparison condition; the temperature difference acquisition module 310 is connected in communication with the comparison condition acquisition module 200 and is used to acquire the current temperature of the power battery when the current temperature exceeds the high temperature threshold. Acquire the temperature difference between the power battery temperature and the ambient temperature; the current output suppression optimization coefficient acquisition module 410 is communicated with the temperature difference acquisition module 310, and is used to acquire the current output suppression optimization coefficient corresponding to the current temperature difference interval according to the acquired temperature difference value, and the current output suppression optimization coefficient is not greater than 1; the optimized current acquisition module 510 is communicated with the current output suppression optimization coefficient acquisition module 410, and is used to acquire the optimized charging current value according to the acquired current output suppression optimization coefficient corresponding to the current temperature difference interval; the first current output control module 610 is communicated with the optimized current acquisition module 510, and is used to control the output of the acquired optimized charging current value to charge the power battery.

[0110] In one embodiment, please refer to Figure 4 By arranging the ambient temperature acquisition module at a suitable location outside the battery system, the battery system management module obtains the real-time ambient temperature T0 through the wiring harness or communication network, and the battery system management module collects the maximum temperature T0 of the battery cell in real time. max , minimum temperature T min , average temperature T avg And other parameters.

[0111] In one embodiment, the output control optimization system for high-temperature DC charging current of a power battery provided in the present application also includes a second current output control module, which is communicatively connected to the comparison operating condition acquisition module and is used to control the output charging current according to a preset battery DC charging matrix table when the current temperature of the power battery does not exceed the high temperature threshold.

[0112] In one embodiment, the power battery high temperature DC charging current output control optimization system provided by the present application further includes:

[0113] A condition-satisfying working condition acquisition module is used to obtain the DC charging condition of the charging pile when the electric vehicle obtains a charging wake-up signal;

[0114] The handshake module is communicatively connected with the condition-satisfying working condition acquisition module, and is used to control the electric vehicle and the charging pile to handshake and exchange information when the charging pile meets the DC charging conditions.

[0115] Based on the same inventive concept, an embodiment of the present application further provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, all or part of the method steps of the above method are implemented.

[0116] The present application implements all or part of the processes in the above method, and can also be completed by instructing related hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the steps of each of the above method embodiments can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electric carrier signal, telecommunication signal and software distribution medium. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electric carrier signals and telecommunication signals.

[0117] Based on the same inventive concept, an embodiment of the present application also provides an electronic device, including a memory and a processor, wherein the memory stores a computer program running on the processor, and when the processor executes the computer program, all or part of the method steps in the above method are implemented.

[0118] The processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc. The processor is the control center of a computer device, and uses various interfaces and lines to connect various parts of the entire computer device.

[0119] The memory can be used to store computer programs and / or modules. The processor realizes various functions of the computer device by running or executing the computer programs and / or modules stored in the memory, and calling the data stored in the memory. The memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system and at least one application required for a function (such as a sound playback function, an image playback function, etc.); the data storage area can store data created according to the use of the mobile phone (such as audio data, video data, etc.). In addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (SmartMediaCard, SMC), a secure digital (SecureDigital, SD) card, a flash card (FlashCard), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0120] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, servers or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) that contain computer-usable program code.

[0121] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), servers, and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0122] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0123] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0124] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A method for optimizing output control of high-temperature DC charging current of a power battery, characterized in that: The steps include: Get the current temperature of the power battery; Compare the current temperature of the power battery with the high temperature threshold to obtain the comparison working condition; When the current temperature of the power battery exceeds the high temperature threshold, the temperature difference between the power battery temperature and the ambient temperature is obtained; According to the obtained temperature difference value, obtain the current output suppression optimization coefficient corresponding to the current temperature difference interval, and the current output suppression optimization coefficient is not greater than 1; Obtain an optimized charging current value according to the current output suppression optimization coefficient corresponding to the current temperature difference range; The optimized charging current value obtained by the control output is used to charge the power battery; The step of obtaining the optimized charging current value according to the current output suppression optimization coefficient corresponding to the current temperature difference interval obtained specifically includes the following steps: Obtaining a first maximum continuous charging current value allowed by the power battery system corresponding to the current temperature of the power battery; Obtaining the second highest continuous charging current value allowed by the power battery system corresponding to the preset temperature rise of the current temperature of the power battery; Obtaining an optimized charging current value according to the obtained first highest continuous charging current value, the second highest continuous charging current value, and the current output suppression optimization coefficient; The first highest continuous charging current value, the second highest continuous charging current value and the current output suppression optimization coefficient are numerically transformed according to the following formula to obtain the optimized charging current value I c : I c =I t+n +k×(I t -I t+n ) In the formula, I c is the charging current value requested by the BMS, I t I is the maximum continuous charging current value allowed by the BMS when the temperature is t. t+n The maximum continuous charging current value allowed by the BMS when the temperature is t+n℃, and n is the increase in the current suppression output required for the battery temperature rise; Among them, the k value is a calibration value, 0≤k<1.

2. The method for optimizing output control of high-temperature DC charging current of a power battery according to claim 1, characterized in that: After the step of comparing the current temperature of the power battery with the high temperature threshold and obtaining the comparison working condition, the following steps are also included: When the current temperature of the power battery does not exceed the high temperature threshold, the control outputs the charging current according to the preset battery DC charging matrix table.

3. The method for optimizing output control of high-temperature DC charging current of a power battery according to claim 1, characterized in that: Before the step of obtaining the current temperature of the power battery, the following steps are also included: When the electric vehicle obtains a charging wake-up signal, the DC charging condition of the charging pile is obtained to meet the working condition; When the charging pile meets the DC charging conditions, the electric vehicle and the charging pile are controlled to handshake to exchange information.

4. The method for optimizing output control of high-temperature DC charging current of a power battery according to claim 1, characterized in that: In the step of obtaining a current output suppression optimization coefficient corresponding to a current temperature difference interval based on the obtained temperature difference value, wherein the current output suppression optimization coefficient is not greater than 1, the larger the temperature difference value is, the smaller the current output suppression optimization coefficient corresponding to the current temperature difference interval is.

5. The method for optimizing output control of high-temperature DC charging current of a power battery according to claim 4, characterized in that: The step of obtaining a current output suppression optimization coefficient corresponding to the current temperature difference interval according to the obtained temperature difference value, wherein the current output suppression optimization coefficient is not greater than 1, specifically comprises the following steps: When the temperature difference value is lower than the first temperature difference threshold, the current output suppression optimization coefficient corresponding to the current temperature difference interval is the first current output suppression optimization coefficient; and / or, When the temperature difference value is between the first temperature difference threshold and the second temperature difference threshold, the current output suppression optimization coefficient corresponding to the current temperature difference interval is the second current output suppression optimization coefficient; and / or, When the temperature difference value is between the second temperature difference threshold and the third temperature difference threshold, the current output suppression optimization coefficient corresponding to the current temperature difference interval is the third current output suppression optimization coefficient; and / or, When the temperature difference value is greater than the third temperature difference threshold, the current output suppression optimization coefficient corresponding to the current temperature difference interval is the fourth current output suppression optimization coefficient; Among them, the first temperature difference threshold value < the second temperature difference threshold value < the third temperature difference threshold value < the fourth temperature difference threshold value, 0≤the fourth current output suppression optimization coefficient < the third current output suppression optimization coefficient < the second current output suppression optimization coefficient < the first current output suppression optimization coefficient≤1.

6. The method for optimizing output control of high-temperature DC charging current of a power battery according to claim 5, characterized in that: The first temperature difference threshold, the second temperature difference threshold and the third temperature difference threshold are calibrated and obtained according to the heat generation and heat exchange amount of the power battery.

7. A power battery high temperature DC charging current output control optimization system, comprising a power battery high temperature DC charging current output control optimization method according to any one of claims 1 to 6, characterized in that: include: The current temperature acquisition module is used to obtain the current temperature of the power battery; A comparison operating condition acquisition module, which is in communication with the current temperature acquisition module and is used to compare the current temperature of the power battery with the high temperature threshold to acquire a comparison operating condition; A temperature difference value acquisition module is connected in communication with the comparison working condition acquisition module, and is used to obtain the temperature difference value between the power battery temperature and the ambient temperature when the current temperature of the power battery exceeds the high temperature threshold; A current output suppression optimization coefficient acquisition module is connected to the temperature difference value acquisition module for acquiring a current output suppression optimization coefficient corresponding to a current temperature difference interval according to the acquired temperature difference value, wherein the current output suppression optimization coefficient is not greater than 1; An optimized current acquisition module is connected to the current output suppression optimization coefficient acquisition module for obtaining an optimized charging current value according to the obtained current output suppression optimization coefficient corresponding to the current temperature difference interval; The first current output control module is in communication with the optimized current acquisition module and is used to control the output of the acquired optimized charging current value to charge the power battery.

8. The power battery high temperature DC charging current output control optimization system according to claim 7, characterized in that: Also includes: The second current output control module is communicatively connected with the comparison working condition acquisition module, and is used for controlling the output of the charging current according to the preset battery DC charging matrix table when the current temperature of the power battery does not exceed the high temperature threshold.

9. The output control optimization system for high-temperature DC charging current of a power battery according to claim 7, characterized in that: Also includes: A condition-satisfying working condition acquisition module is used to obtain the DC charging condition of the charging pile when the electric vehicle obtains a charging wake-up signal; The handshake module is communicatively connected with the condition-satisfying working condition acquisition module, and is used to control the electric vehicle and the charging pile to handshake and exchange information when the charging pile meets the DC charging conditions.

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