Pulse heating method, device and equipment for power battery and storage medium

Abstract

The invention discloses a pulse heating method, device and equipment for a power battery and a storage medium, and relates to the technical field of vehicles. The method comprises the following steps: acquiring an initial temperature and an initial SOC value of a power battery; according to the initial temperature, the initial SOC value and a preset SOC threshold value, determining battery charging durations corresponding to the plurality of candidate first temperature threshold values; wherein each candidate first temperature threshold represents an initial temperature at which the power battery starts to be charged; and screening out a target first temperature threshold meeting a preset battery charging duration condition from the plurality of candidate first temperature thresholds, and performing pulse heating on the power battery according to the target first temperature threshold. According to the technical scheme, the charging time of the power battery can be further shortened on the basis that the power battery is heated in a pulse heating mode in the preheating stage before charging.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a pulse heating method, device, equipment and storage medium for a power battery. Background Art

[0002] Power batteries (e.g., lithium-ion batteries) are widely used in the power systems of electric vehicles. Among them, low temperature is an important application scenario for electric vehicles, and charging at low temperatures will bring many problems to the safety and charging performance of power batteries, such as power battery polarization and lithium deposition at the anode.

[0003] In order to improve the safety and charging performance of power batteries at low temperatures, the charging process of power batteries can usually be divided into three stages when charging at low temperatures, namely: preheating stage before charging, heating while charging stage and charging only stage.

[0004] In the preheating stage before charging, the power battery system can be heated by liquid heating. When the power battery is heated to the charging temperature, it enters the charging and heating stage. Compared with the liquid heating method, the pulse heating (or pulse preheating) method has a higher rate, a faster temperature rise of the power battery, and a higher charging rate, which can greatly shorten the charging time of the power battery. However, pulse heating is only applicable to the preheating stage before charging.

[0005] Therefore, how to further shorten the charging time of the power battery based on the use of pulse heating to heat the power battery in the preheating stage before charging is a problem that urgently needs to be solved. Summary of the invention

[0006] In view of the above problems, the present application provides a pulse heating method, device, equipment and storage medium for a power battery, which are used to solve the problem of relatively long charging time of power batteries in the prior art.

[0007] According to one aspect of an embodiment of the present application, a pulse heating method for a power battery is provided, the method comprising: obtaining an initial temperature and an initial state of charge (SOC) value of the power battery; determining, according to the initial temperature, the initial SOC value and a preset SOC threshold, battery charging times corresponding to a plurality of candidate first temperature thresholds; wherein each candidate first temperature threshold represents: a starting temperature at which the power battery starts charging; from the plurality of candidate first temperature thresholds, screening out a target first temperature threshold that meets a preset battery charging time condition, and performing pulse heating on the power battery according to the target first temperature threshold.

[0008] In an optional exemplary embodiment, the determining of the battery charging times corresponding to a plurality of candidate first temperature thresholds respectively according to the initial temperature, the initial SOC value and the preset SOC threshold further includes: for each of the plurality of candidate first temperature thresholds, performing the following operations respectively: determining the pulse heating time of the power battery in the first stage according to the initial temperature and the candidate first temperature threshold; wherein the first stage is a stage of heating the power battery before charging the power battery; when determining that the temperature of the power battery is the candidate first temperature threshold, determining the actual charging time of the power battery according to the initial SOC value and the SOC threshold; determining the battery charging time corresponding to the candidate first temperature threshold according to the pulse heating time and the actual charging time.

[0009] In an optional exemplary embodiment, determining the pulse heating duration of the power battery based on the initial temperature and a candidate first temperature threshold further includes: determining the pulse heating duration based on the initial temperature, the candidate first temperature threshold and a preset pulse heating heating rate; wherein the pulse heating temperature rise rate represents: the average heating rate of the power battery before charging.

[0010] In an optional exemplary embodiment, determining the actual charging time of the power battery according to the initial SOC value and the SOC threshold further includes: determining the SOC increment and temperature increment of the power battery within a set time according to the first charging current of the power battery in the second stage; wherein the second stage is a stage of charging the power battery during the heating process of the power battery; determining the actual SOC value and actual temperature of the power battery according to the SOC increment and the temperature increment; if the actual temperature is less than or equal to the set second temperature threshold, and the actual SOC value is the SOC threshold, the time required for the SOC value of the power battery to increase from the initial SOC value to the SOC threshold is taken as the actual charging time.

[0011] In an optional exemplary embodiment, the first charging current is a minimum value between a maximum tolerable charging current of the power battery in the second stage and a maximum charging current of a charging device.

[0012] In an optional exemplary embodiment, the method further includes: if the actual temperature is the second temperature threshold and the actual SOC value is less than the SOC threshold, then the time required for the temperature of the power battery to rise from the one candidate first temperature threshold to the second temperature threshold is used as the first charging duration; based on the second charging current of the power battery in the third stage, the time required for the SOC value of the power battery to rise from the actual SOC value to the SOC threshold is determined, and the time is used as the second charging duration; wherein the third stage is the stage of charging the power battery; and the actual charging duration is determined based on the first charging duration and the second charging duration.

[0013] In an optional exemplary embodiment, the second charging current is a minimum value between a maximum tolerable charging current of the power battery in the third stage and a maximum charging current of the charging device.

[0014] According to another aspect of an embodiment of the present application, a pulse heating device for a power battery is provided, the device comprising:

[0015] An acquisition module is used to obtain the initial temperature and initial SOC value of the power battery;

[0016] A determination module, configured to determine the battery charging durations corresponding to a plurality of candidate first temperature thresholds respectively according to the initial temperature, the initial SOC value and a preset SOC threshold; wherein each candidate first temperature threshold represents: a starting temperature at which the power battery starts to be charged;

[0017] The heating module is used to select a target first temperature threshold that meets a preset battery charging time condition from the multiple candidate first temperature thresholds, and perform pulse heating on the power battery according to the target first temperature threshold.

[0018] According to another aspect of the embodiment of the present application, there is also provided an electronic device, including:

[0019] Controller;

[0020] The memory is used to store one or more programs, and when the one or more programs are executed by the controller, the pulse heating method of the power battery is executed.

[0021] According to another aspect of an embodiment of the present application, a computer-readable storage medium is provided, in which a computer program is stored. The computer program includes at least one executable instruction. When the executable instruction is run on a pulse heating device / electronic device of a power battery, the pulse heating device / electronic device of the power battery performs the operation of the above-mentioned pulse heating method of the power battery.

[0022] In the embodiment of the present application, after obtaining the initial temperature and initial SOC value of the power battery through the pulse heating method of the power battery, the battery charging time corresponding to the multiple candidate first temperature thresholds for starting charging of the power battery set for the pulse heating node can be determined according to the initial temperature, initial SOC value and preset SOC threshold of the power battery; so that the target first temperature threshold that meets the preset battery charging time condition can be screened out from the multiple candidate first temperature thresholds to perform pulse heating on the power battery, so as to achieve further shortening of the charging time of the power battery on the basis of heating the power battery by pulse heating in the preheating stage before charging.

[0023] The above description is only an overview of the technical solution of the embodiment of the present application. In order to more clearly understand the technical means of the embodiment of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the embodiment of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings are only used to illustrate the embodiments and are not to be considered as limiting the present application. In addition, the same reference symbols are used to represent the same components throughout the accompanying drawings. In the accompanying drawings:

[0025] Figure 1 A schematic diagram of the architecture of an electric vehicle charging system applicable to the present application is shown;

[0026] Figure 2 A schematic diagram of a process of a pulse heating method for a power battery provided in the present application is shown;

[0027] Figure 3 A schematic diagram of a method for determining battery charging time provided by the present application is shown;

[0028] Figure 4 This application provides a method based on Figure 2 Specific application diagram;

[0029] Figure 5 A schematic structural diagram of a pulse heating device for a power battery provided in the present application is shown;

[0030] Figure 6 A schematic diagram of the structure of a computer system of an electronic device provided by the present application is shown. DETAILED DESCRIPTION

[0031] Here, exemplary embodiments will be described in detail, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are only examples of devices and methods consistent with some aspects of the present application as detailed in the attached claims.

[0032] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities may be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0033] The flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps can be decomposed, and some operations / steps can be combined or partially combined, so the actual execution order may change according to actual conditions.

[0034] The term "multiple" as used in this application refers to two or more than two. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the related objects are in an "or" relationship.

[0035] Before introducing the embodiments of the present application, the relevant terms involved in the present application are first introduced and explained.

[0036] (1) Charging rate is a measure of charging speed. It refers to the current value required when a power battery is charged to its rated capacity within a specified time. The charging rate is numerically equal to the multiple of the rated capacity of the power battery, that is, charging rate = charging current / rated capacity, usually represented by the letter C, where " / " represents the division symbol. For example, if the rated capacity of a power battery is 100 ampere hours (Ah), if the charging current is 5 amperes (A), the charging rate is 0.05C, if the charging current is 20A, the charging rate is 0.2C, and if the charging current is 100A, the charging rate is 1C.

[0037] (2) Map refers to the simulated power point, which is the voltage and current value at which the power battery can provide the maximum output power. It is one of the important parameters for power battery power management and power supply design. Through the MAP value, users can understand the optimal operating range of the power battery, avoid overload or underload operation of the power battery, and thus extend the service life of the power battery.

[0038] (3) Pulse heating uses the Joule heat generated when a pulse current passes through a high-resistance material to heat the power battery. This technology controls the pulse current in the circuit (for example, controls the generation and regulation of the pulse current) so that the current flows quickly in a short period of time, thereby generating a large amount of heat energy inside the battery to achieve the heating effect, thereby effectively improving the performance of the battery in a low-temperature environment.

[0039] (4) SOC is a physical quantity used to reflect the remaining capacity of a battery. Its value is defined as the ratio of the remaining battery capacity to the battery capacity, that is, SOC = remaining battery capacity / battery capacity.

[0040] Exemplarily, the value range of SOC is 0 to 1 (or 0% to 100%), where SOC=0 indicates that the battery is fully discharged, that is, the remaining battery capacity is 0, and SOC=1 indicates that the battery is fully charged, that is, the remaining battery capacity is the same as the battery capacity.

[0041] (5) Lithium-ion battery, also known as lithium battery, is a secondary battery that usually uses lithium compounds such as lithium cobalt oxide, lithium nickel oxide or lithium manganese oxide as the positive electrode material of the battery, and uses carbon materials such as petroleum coke or graphite as the negative electrode material of the battery. Lithium batteries mainly rely on the deintercalation and intercalation of lithium ions (Li+) between the positive and negative electrodes to work.

[0042] For example, during the charging process, lithium ions are extracted from the positive electrode of the battery and enter the electrolyte, and the lithium ions in the electrolyte are embedded in the negative electrode. During the discharging process, the lithium ions embedded in the negative electrode are extracted from the negative electrode and enter the electrolyte, and the lithium ions in the electrolyte are embedded in the positive electrode of the battery.

[0043] Further, based on the above-mentioned nouns and related terminology explanations, the design concept of the embodiments of the present application is briefly introduced below:

[0044] At present, when power batteries (such as lithium-ion batteries) are charged at low temperatures, the charging process can be divided into three stages: the first stage is the preheating stage before charging; the second stage is the heating stage while charging; and the third stage is the charging-only stage. Among them, the power battery system is often heated by liquid heat in the preheating stage before charging. Generally, when the battery is heated to a temperature that can be charged, it enters the heating stage while charging.

[0045] However, compared with the liquid heating method, the pulse heating (or pulse preheating) rate is higher, the battery system temperature rises faster, and the charging rate is higher, which greatly shortens the time required for the first stage mentioned above, thereby shortening the charging time of the power battery. But it is only applicable to the preheating stage before charging. For example, in the stage of heating while charging, only the traditional liquid heating method can be used to heat the power battery system. Therefore, after the introduction of the pulse heating method, how to further shorten the charging time of the power battery is an urgent problem to be solved.

[0046] In view of this, in order to further shorten the charging time of the power battery, the present application proposes a pulse heating method for a power battery, which specifically includes: obtaining the initial temperature and initial SOC value of the power battery; then, according to the initial temperature, the initial SOC value and the preset SOC threshold, determining the battery charging time corresponding to multiple candidate first temperature thresholds; finally, screening out the target first temperature threshold that meets the preset battery charging time condition from multiple candidate first temperature thresholds, and pulse heating the power battery according to the target first temperature threshold. Among them, each candidate first temperature threshold represents: the starting temperature at which the power battery starts charging, that is, each of the aforementioned first temperature thresholds is the temperature (threshold) at which the preheating stage before charging exits. Since the temperature (threshold) at which the preheating stage before charging exits is an important factor affecting the charging time of the power battery. Therefore, selecting a suitable target first temperature threshold from multiple candidate first temperature thresholds can further shorten the charging time of the power battery (or power battery system).

[0047] In particular, the preferred embodiments of the present application are described below in conjunction with the drawings in the specification. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application, and the embodiments of the present application and the features in the embodiments may be combined with each other if there is no conflict.

[0048] See also Figure 1 As shown, it is a schematic diagram of the architecture of an electric vehicle charging system applicable to an embodiment of the present application. The electric vehicle charging system may include a vehicle 11 and a charging device 12. The vehicle 11 and the charging device 12 are electrically connected during the charging process to ensure that the power battery of the vehicle 11 can be charged smoothly. The embodiment of the present application does not limit the specific connection method between the vehicle 11 and the charging device 12.

[0049] The embodiment of the present application does not limit the number of devices involved in the above system architecture. For example, there may be more charging devices 12, or other devices may be included, such as Figure 1 As shown, only the vehicle 11 and the charging device 12 are described as an example, and the above devices are briefly introduced below.

[0050] like Figure 1As shown, the vehicle 11 may include a power battery 111, a battery management system (BMS) 112, and a thermal management system (TMS) 113. Any two of the battery management system 112, the thermal management system 113, and the charging device 12 may exchange information through a communication network, wherein the communication network may use a wireless communication method and a wired communication method.

[0051] Exemplarily, the charging device 12 can access the network through cellular mobile communication technology to communicate with the battery management system 112 and the thermal management system 113, wherein the cellular mobile communication technology, for example, includes the fifth generation (5G) mobile communication technology or the next generation mobile communication technology. Optionally, the charging device 12 can also access the network through short-range wireless communication mode to communicate with the battery management system 112 and the thermal management system 113, wherein the short-range wireless communication mode, for example, includes wireless fidelity (Wi-Fi) technology.

[0052] In an optional implementation, the user can send a demand current instruction to the charging device 12 through the battery management system 112, so that the charging device 12 can input the charging current to the power battery 111 and the thermal management system 113 according to the demand current instruction output by the battery management system 112 and the current supply capability of the charging device 12 itself. The battery management system 112 can also determine the current state of the power battery 111 based on the detected voltage, current and temperature of the power battery 111, and request corresponding thermal management. After receiving the thermal management request output by the battery management system 112, the thermal management system 113 can heat, cool or evenly treat the power battery 111. Exemplarily, the thermal management system 113 can affect the temperature of the power battery 111 by adjusting the temperature of the coolant, thereby changing the sustainable charging current of the power battery 111.

[0053] It should be noted that the power battery 111 can directly or indirectly provide power for the vehicle 11, and is a general term for rechargeable chemical energy storage devices such as lead-acid batteries, nickel-cadmium batteries, nickel-metal hydride batteries, lithium batteries, and supercapacitors. In particular, the power battery 111 may include a single electrochemical battery cell, may include multiple electrochemical battery cells, may include a battery pack, etc., and this application does not make specific limitations on this.

[0054] The charging device 12 may be a charger, a charging pile or a vehicle charger, for example, Figure 1The charging device 12 is a charging pile. This embodiment of the present application does not specifically limit this.

[0055] The pulse heating method of the power battery provided by the exemplary embodiment of the present application is described below in combination with the above-mentioned system architecture and with reference to the accompanying drawings. It should be noted that the above-mentioned system architecture is only shown to facilitate understanding of the spirit and principles of the present application, and the implementation of the present application is not limited in this respect.

[0056] See also Figure 2 As shown in FIG. 1 , a flow chart of a pulse heating method for a power battery provided in an embodiment of the present application is shown. In the following introduction, for the convenience of description and understanding, the pulse heating method for a power battery is applied to the following examples. Figure 1 The battery management system shown in the figure is used as an example. Figure 2 As shown, the specific implementation process of this method is as follows:

[0057] Step 210: Obtain the initial temperature and initial SOC value of the power battery.

[0058] The initial temperature of the power battery can be obtained by the battery management system through temperature sensor temperature acquisition of the power battery. Optionally, the battery management system can respond to a power battery charging request initiated by a user to obtain the initial temperature of the power battery acquired by the temperature sensor. For example, the initial temperature of the power battery acquired by the battery management system through the temperature sensor is 15°C.

[0059] In another optional implementation, in order to save the speed of the battery management system acquiring the initial temperature of the power battery, the temperature sensor can collect the temperature of the power battery according to a set power battery temperature collection cycle or continuously. In this way, after the battery management system receives the power battery charging request, it can quickly obtain the initial temperature of the power battery.

[0060] In addition, if the vehicle (or power battery) is in a certain environment for a long time, and the power battery is not in working state for a long time, the ambient temperature of the environment where the vehicle (or power battery) is located can be used as the initial temperature of the power battery. It should be understood that the initial temperature of the power battery is the temperature of the power battery when it is about to enter the first stage (i.e., the preheating stage before charging) of the three charging stages mentioned above.

[0061] Similarly, the initial SOC value of the power battery can be obtained by the battery management system through the SOC detection device. For example, the SOC detection device can record the SOC value of the power battery in real time. In this way, after the battery management system receives the above-mentioned power battery charging request, it can quickly obtain the initial SOC value of the power battery through the aforementioned SOC detection device. For example, the initial SOC value of the aforementioned power battery can be 3%. It should be understood that the initial SOC value of the power battery is also the SOC value of the power battery when it is about to enter the first of the three charging stages mentioned above.

[0062] It should be noted that the battery management system can simultaneously obtain the initial temperature of the power battery and the initial SOC value of the power battery. Of course, it is also possible not to obtain the initial temperature of the power battery and the initial SOC value of the power battery at the same time. This embodiment of the present application does not specifically limit this.

[0063] Exemplarily, the battery management system can simultaneously obtain the initial temperature and initial SOC value of the power battery when the power battery is about to enter the first of the three charging stages. For another example, the battery management system can only obtain the initial temperature of the power battery when the power battery is about to enter the first of the three charging stages, and then obtain the initial SOC value of the power battery when the power battery is about to enter the second of the three charging stages (i.e., the charging and heating stage).

[0064] Step 220: Determine the battery charging durations corresponding to a plurality of candidate first temperature thresholds according to the initial temperature, the initial SOC value and the preset SOC threshold.

[0065] The multiple candidate first temperature thresholds may be predefined or specified in accordance with relevant specifications, which is not limited in the present embodiment. Each candidate first temperature threshold is the temperature at which the power battery enters the second stage from the first stage of the three charging stages.

[0066] The preset SOC threshold is the SOC value of the power battery after charging is completed. For example, the preset SOC threshold is 100%; for another example, the preset SOC threshold can also be 95%. The specific value of the preset SOC threshold is not limited in the embodiment of the present application. It should also be noted that the preset SOC threshold can also be called the target SOC value, and of course it can also have other names.

[0067] In an optional implementation, after executing step 220, the battery management system can determine the battery charging time corresponding to each of the above-mentioned multiple candidate first temperature thresholds according to the initial temperature and the initial SOC value after obtaining the initial temperature and the initial SOC value, so that the target first temperature threshold that meets the preset battery charging time condition can be screened out from the above-mentioned multiple candidate first temperature thresholds, thereby performing pulse heating on the power battery according to the target first temperature threshold to further shorten the charging time of the power battery. Optionally, refer to Figure 3 As shown, the battery management system performs the following operations respectively for the above-mentioned multiple candidate first temperature thresholds:

[0068] Step 310: Determine the pulse heating duration of the power battery in the first stage according to the initial temperature and a candidate first temperature threshold.

[0069] The first stage is a stage of heating the power battery before charging the power battery, that is, a preheating stage before charging. Since in the embodiment of the present application, a pulse heating (or pulse preheating) method is used to heat (or preheat) the power battery before charging the power battery, the first stage can also be referred to as a pulse heating stage or a pulse preheating stage.

[0070] For example, if the first temperature threshold can be expressed as T a , then any one of the multiple candidate first temperature thresholds (i.e., the one candidate first temperature threshold) can be expressed as T a,i , wherein i indicates that the candidate first temperature threshold is the i-th candidate first temperature threshold among the above-mentioned multiple candidate first temperature thresholds.

[0071] In an optional implementation, when executing step 310, the battery management system can determine the pulse heating duration of the power battery according to the initial temperature, the above-mentioned candidate first temperature threshold and the preset pulse heating heating rate; wherein the pulse heating rate represents: the average heating rate of the power battery before charging. Exemplarily, the calculation formula of the above-mentioned pulse heating duration can be expressed as follows:

[0072]

[0073] Among them, t a is the pulse heating duration, T a,i is a candidate first temperature threshold mentioned above, T m is the initial temperature of the power battery, and α is the above-mentioned preset pulse heating heating rate.

[0074] It should be understood that the pulse heating time t aThat is, the duration that the power battery is in the first stage or the duration of the first stage.

[0075] Assume that the above candidate first temperature threshold T a,i =22℃、T m =18℃ and α = 0.05℃ / S (or degrees Celsius / second), then the pulse heating time of the power battery is t a =(22-18) / 0.05=80S.

[0076] Step 320: When it is determined that the temperature of the power battery is a candidate first temperature threshold, the actual charging time of the power battery is determined according to the initial SOC value and the SOC threshold.

[0077] It should be noted that when the battery management system determines that the temperature of the power battery is the above-mentioned candidate first temperature threshold, it can determine that the charging process of the power battery has entered the second stage (i.e., the charging and heating stage) of the three charging stages mentioned above.

[0078] In an optional implementation, when the battery management system determines that the temperature of the power battery is a candidate first temperature threshold, it can determine the SOC increment and temperature increment of the power battery within a set time based on the first charging current of the power battery in the second stage; wherein the second stage is the stage of charging the power battery while heating the power battery, that is, the stage of charging and heating.

[0079] The above-mentioned set time can be a unit time t0, or can be other set durations. The embodiment of the present application does not limit this. For ease of understanding, the following text will describe the above-mentioned set time as the unit time t0.

[0080] Optionally, the first charging current may be the minimum value between the maximum tolerable charging current of the power battery in the second stage and the maximum charging current of the charging device. The maximum tolerable charging current may be determined by the battery management system according to the initial SOC value of the power battery, the temperature of the power battery (i.e., the first candidate temperature threshold) and the charging map. If the maximum tolerable charging current is expressed as I0 a The maximum charging current of the aforementioned charging equipment (such as a charging pile) is expressed as I 设备 , then the first charging current can be expressed as I a =min(I0 a , I 设备 ). For example, assuming I0 a =30A and I 设备 =45A, then the first charging current can be I a =min(30A, 45A)=30A.

[0081] It should be noted that due to the aforementioned maximum tolerable charging current I0 a Usually it changes with the state of the power battery (for example, the temperature and SOC value of the power battery), so the SOC increment and temperature increment within different set times (ie, unit time) in the second stage are usually different.

[0082] In an optional implementation, the calculation formula of the SOC increment of the power battery within a set time in the second stage is as follows:

[0083]

[0084] Among them, ΔSOC a is the SOC increment within the set time in the second stage, ΔQ a Q is the charge increment within the set time in the second stage. c It is the charge capacity of the power battery (i.e. battery capacity).

[0085] Optionally, the charge increment ΔQ within a set time in the second stage a The calculation formula can be expressed as follows:

[0086] ΔQ a =I a *t0

[0087] Among them, I a is the first charging current (i.e., the actual current for charging the power battery in the second stage), and t0 is the set time (i.e., unit time). Optionally, the calculation formula for the temperature increment of the power battery within the set time in the second stage is as follows:

[0088]

[0089] Among them, R is the internal resistance of the power battery, C is the specific heat capacity of the battery, m is the mass of the power battery, A w can be the heat exchange area between the liquid thermal system and the power battery, h w can be the heat transfer coefficient between the liquid thermal system and the power battery, T w Can heat water temperature for liquid thermal system, A e can be the heat exchange area between the power battery and the environment, h e It can be the heat transfer coefficient between the power battery and the environment, T e It can be the ambient temperature.

[0090] Furthermore, after obtaining the SOC increment and temperature increment within the set time, the battery management system can determine the actual SOC value and actual temperature of the power battery according to the obtained SOC increment and temperature increment. Specifically, the battery management system can determine the actual SOC value of the power battery according to the aforementioned SOC increment and the aforementioned initial SOC value, and determine the actual temperature of the power battery according to the aforementioned temperature increment and the aforementioned first temperature threshold.

[0091] Optionally, the actual SOC value of the power battery can be expressed as follows:

[0092]

[0093] Among them, SOC pra is the actual SOC value of the power battery, SOC init is the initial SOC value of the power battery, ΔSOC a,i is the SOC increment within the i-th set time after entering the above-mentioned second stage (i.e., the charging and heating stage), and N is the number of set times.

[0094] In this way, the battery management system can detect the actual SOC value of the power battery in the above-mentioned second stage, with the set time as the detection cycle of the power battery SOC, until the actual temperature of the power battery rises to the set second temperature threshold, or the actual SOC of the power battery rises to the above-mentioned SOC threshold.

[0095] It should be noted that the second temperature threshold set above is the temperature at which the power battery enters the third stage from the second stage of the three charging stages mentioned above, and can also be understood as the temperature (threshold) at which the second stage (i.e., the charging and heating stage) is exited. Optionally, the battery management system can accumulate the charging time of the second stage as t b =t0*n, where n is the number of loop calculations (i.e., the number of set times in the second stage).

[0096] Based on the actual temperature and actual SOC value of the power battery, the battery management system usually has the following situations when determining the actual charging time of the power battery:

[0097] (1): If the actual temperature of the power battery is less than or equal to the second temperature threshold set above, and the actual SOC value of the power battery is the above SOC threshold, the battery management system may take the time required for the SOC value of the power battery to rise from the above initial SOC value to the above SOC threshold as the actual charging time. In other words, the charging time of the second stage is the actual charging time of the power battery. For example, the actual charging time of the power battery can be expressed as: t act =t b .

[0098] (2): If the actual temperature of the power battery is the above-mentioned second temperature threshold, and the actual SOC value of the power battery is less than the above-mentioned SOC threshold, the battery management system may use the time required for the temperature of the power battery to rise from the above-mentioned candidate first temperature threshold to the above-mentioned second temperature threshold as the first charging duration. The above-mentioned first charging duration is also the charging duration of the above-mentioned second stage. Exemplarily, the above-mentioned first charging duration can be expressed as: t1 = t b .

[0099] Furthermore, the battery management system can determine the time required for the SOC value of the power battery to rise from the actual SOC value to the SOC threshold value according to the second charging current of the power battery in the third stage, and use the time as the second charging duration. The third stage is a stage in which only the power battery is charged, that is, a charging-only stage.

[0100] Optionally, the second charging current may be the minimum value of the maximum tolerable charging current of the power battery in the third stage and the maximum charging current of the charging device. The maximum tolerable charging current at this time may be determined by the battery management system according to the current SOC value of the power battery, the current temperature of the power battery (i.e., the second temperature threshold) and the charging map. Similarly, if the maximum tolerable charging current is expressed as I0 b The maximum charging current of the above charging device is expressed as I 设备 , then the second charging current can be expressed as I b =min(I0 b , I 设备 ). For example, assuming I0 b =55A and I 设备 =45A, then the second charging current can be I a =min(55A, 45A)=45A.

[0101] It should be noted that due to the aforementioned maximum tolerable charging current I0 b Usually, it will also change with the state of the power battery (for example, the temperature and SOC value of the power battery), so the SOC increment and temperature increment within different set times (ie, unit time) in the third stage are usually different.

[0102] In an optional implementation, the calculation formula for the SOC increment of the power battery within a set time in the third stage is as follows:

[0103]

[0104] Among them, ΔSOC b is the SOC increment within the set time in the third stage, ΔQ bQ is the charge increment within the set time in the third stage. c is the charge capacity of the power battery (i.e., the battery capacity). Optionally, the charge increment ΔQ within the set time in the third stage is b The calculation formula can be expressed as follows:

[0105] ΔQ b =I b *t0

[0106] Among them, I b is the second charging current (i.e., the actual current for charging the power battery in the third stage), and t0 is the set time (i.e., the unit time). Optionally, the battery management system can accumulate the charging time of the third stage as t c =t0*m, where m is the number of cycle calculations (i.e., the number of set times in the third stage). In other words, the time required for the SOC value of the power battery to rise from the above actual SOC value to the above SOC threshold value is the charging time of the third stage. For example, the first charging time can be expressed as: t2=t c .

[0107] Since the temperature of the power battery will also increase during the charging process of the third stage, the battery management system can also determine the temperature increment of the power battery within the set time in the third stage according to the second charging current of the power battery, so as to avoid the danger caused by the power battery being overcharged. Optionally, the calculation formula of the temperature increment of the power battery within the set time in the third stage is as follows:

[0108]

[0109] Among them, R is the internal resistance of the power battery, C is the specific heat capacity of the battery, m is the mass of the power battery, A e is the heat exchange area between the power battery and the environment, h e is the heat transfer coefficient between the power battery and the environment, T e is the ambient temperature.

[0110] Finally, after obtaining the first charging time and the second charging time, the battery management system can determine the actual charging time of the power battery according to the first charging time and the second charging time. act =t1+t2=t b +t c .

[0111] Based on the above two situations of determining the actual charging time (i.e., the above method 1 and the above method 2), it is not difficult to find that: if the actual temperature of the power battery is less than or equal to the above-set second temperature threshold, and the actual SOC value of the power battery is the above-mentioned SOC threshold, then the power battery is charged in the second stage, that is, under the above conditions, the second charging time t2=t c =0.

[0112] In this way, the battery management system can obtain the actual charging time of the power battery, or the charging time of the second stage (ie, the first charging time) and the charging time of the third stage (ie, the second charging time).

[0113] Step 330: Determine a battery charging time corresponding to a candidate first temperature threshold according to the pulse heating time and the actual charging time.

[0114] Exemplarily, when executing step 330, the battery management system obtains the pulse heating duration and the actual charging duration, and can determine the battery charging duration corresponding to the above-mentioned candidate first temperature threshold according to the pulse heating duration and the actual charging duration, as well as the preset battery charging duration calculation formula. The above-mentioned battery charging duration calculation formula can be specifically expressed as follows:

[0115] t s =t a +t act

[0116] Among them, t s Charging time of the battery, t a is the pulse heating duration, t act The actual charging time.

[0117] Obviously, based on the method steps described in S310 to S330 above, the battery management system can determine the battery charging times corresponding to the multiple candidate first temperature thresholds according to the initial temperature, the initial SOC value and the preset SOC threshold.

[0118] Step 230: Filter out a target first temperature threshold that meets a preset battery charging time condition from a plurality of candidate first temperature thresholds, and pulse heat the power battery according to the target first temperature threshold.

[0119] Exemplarily, when executing step 230, refer to Figure 4 As shown, taking five candidate first temperature thresholds as an example, it is assumed that the five candidate first temperature thresholds are: T a,1 =21℃、T a,2 =22℃、T a,3 =23℃、T a,4 =24℃、T a,5=25°C, the battery charging times corresponding to the above five candidate first temperature thresholds are: t s,1 =55min, t s,2 =1h2min, t s,3 =45min, t s,4 =1h15min and t s,5 =57min. If the above preset battery charging time condition is the shortest battery charging time, the battery management system can determine that among the above five candidate first temperature thresholds, T a,3 The corresponding battery charging time is the shortest, so the candidate first temperature threshold T a,3 The target first temperature threshold is used as the target first temperature threshold to meet the above preset battery charging time condition, and the power battery is pulse heated according to the target first temperature threshold.

[0120] In summary, in the pulse heating method of the power battery provided in the embodiment of the present application, after the initial temperature and the initial SOC value of the power battery are obtained, the battery charging times corresponding to the multiple candidate first temperature thresholds for starting charging of the power battery set for the pulse heating node can be determined according to the initial temperature, the initial SOC value and the preset SOC threshold of the power battery; in this way, the target first temperature threshold that meets the preset battery charging time condition can be screened out from the multiple candidate first temperature thresholds to perform pulse heating on the power battery, so as to further shorten the charging time of the power battery on the basis of heating the power battery by pulse heating in the preheating stage before charging.

[0121] Another aspect of the present application also provides a pulse heating device for a power battery, see Figure 5 As shown, it is a schematic diagram of the structure of a pulse heating device for a power battery provided in an embodiment of the present application. The pulse heating device 500 for a power battery includes: an acquisition module 510, a determination module 520 and a heating module 530;

[0122] An acquisition module 510 is used to acquire an initial temperature and an initial SOC value of the power battery;

[0123] The determination module 520 is used to determine the battery charging time corresponding to a plurality of candidate first temperature thresholds according to the initial temperature, the initial SOC value and the preset SOC threshold; wherein each candidate first temperature threshold represents: the starting temperature at which the power battery starts charging;

[0124] The heating module 530 is used to select a target first temperature threshold that meets a preset battery charging time condition from a plurality of candidate first temperature thresholds, and perform pulse heating on the power battery according to the target first temperature threshold.

[0125] In an optional manner, the determination module 520 further includes: a first determination module, a second determination module and a third determination module; for multiple candidate first temperature thresholds, the following operations are performed respectively: a first determination module, used to determine the pulse heating duration of the power battery in the first stage according to the initial temperature and a candidate first temperature threshold; wherein the first stage is the stage of heating the power battery before charging the power battery; a second determination module, used to determine the actual charging duration of the power battery according to the initial SOC value and the SOC threshold when determining that the temperature of the power battery is a candidate first temperature threshold; a third determination module, used to determine the battery charging duration corresponding to a candidate first temperature threshold according to the pulse heating duration and the actual charging duration.

[0126] In an optional manner, the first determination module is specifically used to determine the pulse heating duration based on the initial temperature, a candidate first temperature threshold and a preset pulse heating heating rate; wherein the pulse heating heating rate represents: the average heating rate of the power battery before charging.

[0127] In an optional manner, the second determination module is specifically used to determine the SOC increment and temperature increment of the power battery within a set time according to the first charging current of the power battery in the second stage; wherein the second stage is the stage of charging the power battery during the heating process of the power battery; according to the SOC increment and the temperature increment, the actual SOC value and the actual temperature of the power battery are determined; if the actual temperature is less than or equal to the set second temperature threshold, and the actual SOC value is the SOC threshold, the time required for the SOC value of the power battery to increase from the initial SOC value to the SOC threshold is used as the actual charging time.

[0128] In an optional manner, the second determination module is also used to, if the actual temperature is the second temperature threshold and the actual SOC value is less than the SOC threshold, use the time required for the temperature of the power battery to rise from a candidate first temperature threshold to the second temperature threshold as the first charging duration; determine the time required for the SOC value of the power battery to rise from the actual SOC value to the SOC threshold based on the second charging current of the power battery in the third stage, and use the time as the second charging duration; wherein the third stage is the stage of charging the power battery; and determine the actual charging duration based on the first charging duration and the second charging duration.

[0129] It should be noted that the pulse heating device for the power battery provided in the above embodiment and the pulse heating method for the power battery provided in the aforementioned embodiment belong to the same concept, wherein the specific manner in which each module and unit performs the operation has been described in detail in the method embodiment and will not be repeated here.

[0130] Another aspect of the present application also provides an electronic device. Figure 6As shown, it shows a schematic diagram of the structure of a computer system suitable for implementing an electronic device of an embodiment of the present application. The specific embodiment of the present application does not limit the specific implementation of the electronic device.

[0131] See also Figure 6 As shown, the electronic device includes: a controller; a memory for storing one or more programs, and when the one or more programs are executed by the controller, the pulse heating method of the power battery is executed. Figure 6 As shown, the computer system 600 of the electronic device includes a central processing unit (CPU) 601, which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 602 or the program loaded from the storage part 608 to the random access memory (RAM) 603, such as executing the method in the above embodiment. In RAM 603, various programs and data required for system operation are also stored. CPU 601, ROM 602 and RAM 603 are connected to each other through bus 604. Input / output (I / O) interface 605 is also connected to bus 604.

[0132] In particular, according to an embodiment of the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present application includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a computer program for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication section 609, and / or installed from a removable medium 611. When the computer program is executed by the CPU 601, various functions defined in the system of the present application are executed.

[0133] Another aspect of the present application further provides a computer-readable storage medium having a computer program stored thereon, which implements the pulse heating method of the power battery as described above when the computer program is executed by a processor. The computer-readable storage medium may be included in the electronic device described in the above embodiment, or may exist independently without being assembled into the electronic device.

[0134] Another aspect of the present application also provides a computer program product or a computer program, which includes at least one executable instruction. When the executable instruction is run on a pulse heating device or an electronic device of a power battery, the pulse heating device or the electronic device of the power battery executes the pulse heating method of the power battery as described above.

[0135] It should be noted that the computer-readable medium shown in the embodiment of the present application may be a computer-readable signal medium or a computer-readable storage medium or any combination of the above two. The computer-readable storage medium may be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, RAM, ROM, an erasable programmable read only memory (EPROM), a flash memory, an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present application, a computer-readable storage medium may be any tangible medium containing or storing a program, which may be used by an instruction execution system, device or device or used in combination with it. In the present application, a computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave, in which a computer-readable computer program is carried. This propagated data signal may take a variety of forms, including but not limited to an electromagnetic signal, an optical signal, or any suitable combination of the above. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate or transmit a program for use by or in conjunction with an instruction execution system, apparatus or device. A computer program contained on a computer-readable medium may be transmitted using any appropriate medium, including but not limited to: wireless, wired, etc., or any suitable combination of the above.

[0136] The flowchart and block diagram in the accompanying drawings illustrate the possible architecture, functions and operations of the system, method and computer program product according to various embodiments of the present application. Wherein, each box in the flowchart or block diagram can represent a module, a program segment, or a part of the code, and the above-mentioned module, program segment, or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order than the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of boxes in the block diagram or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0137] The units involved in the embodiments described in this application may be implemented by software or hardware, and the units described may also be set in a processor. The names of these units do not, in some cases, constitute limitations on the units themselves.

[0138] According to one aspect of the embodiment of the present application, a computer system is also provided, including a CPU, which can perform various appropriate actions and processes according to the program stored in the ROM or the program loaded from the storage part into the random access memory RAM, such as executing the method in the above embodiment. Various programs and data required for system operation are also stored in the RAM. The CPU, ROM and RAM are connected to each other through a bus. The I / O interface is also connected to the bus.

[0139] The following components are connected to the I / O interface: an input part including a keyboard, a mouse, etc.; an output part including a cathode ray tube (CRT), a liquid crystal display (LCD), etc., and a speaker; a storage part including a hard disk, etc.; and a communication part including a network interface card such as a local area network (LAN) card, a modem, etc. The communication part performs communication processing via a network such as the Internet. A drive is also connected to the I / O interface as needed. Removable media, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., are installed on the drive as needed so that the computer program read therefrom is installed into the storage part as needed.

[0140] The above content is only a preferred exemplary embodiment of the present application and is not intended to limit the implementation scheme of the present application. A person skilled in the art can easily make corresponding changes or modifications based on the main concept and spirit of the present application. Therefore, the scope of protection of the present application shall be based on the scope of protection required by the claims.

Claims

1. A pulse heating method for a power battery, characterized in that: The method comprises: Obtain the initial temperature and initial SOC value of the power battery; According to the initial temperature, the initial SOC value and the preset SOC threshold, determining the battery charging durations corresponding to a plurality of candidate first temperature thresholds respectively; wherein each candidate first temperature threshold represents: the starting temperature at which the power battery starts to be charged; A target first temperature threshold that meets a preset battery charging time condition is screened out from the multiple candidate first temperature thresholds, and pulse heating is performed on the power battery according to the target first temperature threshold.

2. The method according to claim 1, characterized in that: The determining, according to the initial temperature, the initial SOC value and the preset SOC threshold, the battery charging durations corresponding to a plurality of candidate first temperature thresholds respectively further comprises: For each of the plurality of candidate first temperature thresholds, the following operations are performed: Determining the pulse heating duration of the power battery in the first stage according to the initial temperature and the candidate first temperature threshold; wherein the first stage is a stage of heating the power battery before charging the power battery; When it is determined that the temperature of the power battery is the candidate first temperature threshold, determining an actual charging time of the power battery according to the initial SOC value and the SOC threshold; The battery charging time corresponding to the candidate first temperature threshold is determined according to the pulse heating time and the actual charging time.

3. The method according to claim 2, characterized in that The step of determining the pulse heating duration of the power battery according to the initial temperature and the candidate first temperature threshold further includes: The pulse heating duration is determined according to the initial temperature, the candidate first temperature threshold and a preset pulse heating temperature rise rate; wherein the pulse heating temperature rise rate represents: an average temperature rise rate of the power battery before charging.

4. The method according to claim 2, characterized in that: The determining the actual charging time of the power battery according to the initial SOC value and the SOC threshold further includes: determining, according to the first charging current of the power battery in the second stage, an SOC increment and a temperature increment of the power battery within a set time; wherein the second stage is a stage of charging the power battery during the heating process of the power battery; Determining an actual SOC value and an actual temperature of the power battery according to the SOC increment and the temperature increment; If the actual temperature is less than or equal to the set second temperature threshold, and the actual SOC value is the SOC threshold, the time required for the SOC value of the power battery to increase from the initial SOC value to the SOC threshold is taken as the actual charging duration.

5. The method according to claim 4, characterized in that The first charging current is a minimum value between a maximum tolerable charging current of the power battery in the second stage and a maximum charging current of a charging device.

6. The method according to claim 4 or 5, characterized in that: The method further comprises: If the actual temperature is the second temperature threshold and the actual SOC value is less than the SOC threshold, the time required for the temperature of the power battery to rise from the one candidate first temperature threshold to the second temperature threshold is used as the first charging duration; According to the second charging current of the power battery in the third stage, determining the time required for the SOC value of the power battery to rise from the actual SOC value to the SOC threshold, and taking the time as the second charging duration; wherein the third stage is a stage for charging the power battery; The actual charging duration is determined according to the first charging duration and the second charging duration.

7. The method according to claim 6, characterized in that The second charging current is a minimum value between a maximum tolerable charging current of the power battery in the third stage and a maximum charging current of the charging device.

8. A pulse heating device for a power battery, characterized in that: The device comprises: An acquisition module is used to obtain the initial temperature and initial SOC value of the power battery; A determination module, configured to determine the battery charging durations corresponding to a plurality of candidate first temperature thresholds respectively according to the initial temperature, the initial SOC value and a preset SOC threshold; wherein each candidate first temperature threshold represents: a starting temperature at which the power battery starts to be charged; The heating module is used to select a target first temperature threshold that meets a preset battery charging time condition from the multiple candidate first temperature thresholds, and perform pulse heating on the power battery according to the target first temperature threshold.

9. An electronic device, characterized in that: include: Controller; A memory for storing one or more programs, which, when executed by the controller, enables the controller to implement the pulse heating method for a power battery as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The storage medium stores a computer program, which includes at least one executable instruction. When the executable instruction is executed on the pulse heating device / electronic device of the power battery, the pulse heating device / electronic device of the power battery performs the operation of the pulse heating method of the power battery as described in any one of claims 1 to 7.

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