阅读说明：本技术 电池的充电控制方法、装置、电池管理系统和介质 (Battery charging control method, device, battery management system and medium ) 是由 杜明树 李世超 吴维清 张伟 于 2020-04-23 设计创作，主要内容包括：本发明公开了一种电池的充电控制方法、装置、电池管理系统和介质。该方法包括：基于接收的充电请求,获取电池的充电参数的阈值和初始值；充电参数的阈值是基于电池的实际容量值和所在的电动汽车的累计行驶里程确定的；若充电参数的初始值小于充电参数的阈值,发送对电池进行充电的控制命令,以对电池进行充电；在电池的充电过程中,实时获取电池的充电参数的数值；若获取的电池的充电参数的数值大于或等于充电参数的阈值,则发送停止对电池充电的控制命令,以停止充电。根据本发明实施例,提高了电池的使用安全性。(The invention discloses a battery charging control method, a battery charging control device, a battery management system and a medium. The method comprises the following steps: acquiring a threshold value and an initial value of a charging parameter of the battery based on the received charging request; the threshold value of the charging parameter is determined based on the actual capacity value of the battery and the accumulated driving mileage of the electric automobile; if the initial value of the charging parameter is smaller than the threshold value of the charging parameter, sending a control command for charging the battery so as to charge the battery; acquiring the numerical value of the charging parameter of the battery in real time in the charging process of the battery; and if the acquired numerical value of the charging parameter of the battery is larger than or equal to the threshold value of the charging parameter, sending a control command for stopping charging the battery so as to stop charging. According to the embodiment of the invention, the use safety of the battery is improved.)

1. A method for controlling charging of a battery, the method comprising:

acquiring a threshold value and an initial value of a charging parameter of the battery based on the received charging request; the threshold value of the charging parameter is determined based on the actual capacity value of the battery and the accumulated driving mileage of the electric automobile;

if the initial value of the charging parameter is smaller than the threshold value of the charging parameter, sending a control command for charging the battery so as to charge the battery;

acquiring the numerical value of the charging parameter of the battery in real time in the charging process of the battery;

and if the acquired value of the charging parameter of the battery is larger than or equal to the threshold value of the charging parameter, sending a control command for stopping charging the battery so as to stop charging.

2. The method of claim 1, wherein prior to said obtaining threshold and initial values for charging parameters of a battery based on a received charge request, the method further comprises:

determining a chargeable capacity upper limit value of the battery based on the actual capacity value of the battery and the accumulated mileage;

determining a threshold value of the charging parameter based on the actual capacity value and the chargeable capacity upper limit value.

3. The method of claim 2, wherein the charging parameter is a state of charge, SOC, and accordingly the threshold value of the charging parameter comprises a charging SOC threshold value;

wherein the determining a threshold value for a charging parameter of the battery based on the actual capacity value and the chargeable capacity upper limit value comprises:

and taking the ratio of the chargeable capacity upper limit value to the actual capacity value as a charging SOC threshold value of the battery.

4. The method of claim 2, wherein the charging parameter is a charging voltage, and accordingly, the threshold value of the charging parameter comprises a charging voltage threshold value;

wherein the determining the threshold value of the charging parameter based on the actual capacity value and the chargeable capacity upper limit value includes:

taking a ratio of the chargeable capacity upper limit value to the actual capacity value as a charging SOC threshold value of the battery;

determining a charging voltage threshold of the battery based on the charging SOC threshold, the acquired current temperature of the battery and a preset first corresponding relation;

the first corresponding relation is the corresponding relation between voltage and a first parameter, and the first parameter comprises temperature and SOC.

5. The method of claim 2, wherein the charging parameters comprise a charging voltage and a charging SOC, and wherein the thresholds for the charging parameters comprise a charging SOC threshold and a charging voltage threshold, respectively;

wherein the determining the threshold value of the charging parameter based on the actual capacity value and the chargeable capacity upper limit value includes:

taking a ratio of the chargeable capacity upper limit value to the actual capacity value as a charging SOC threshold value of the battery;

determining a charging voltage threshold of the battery based on the charging SOC threshold, the acquired current temperature of the battery and a preset first corresponding relation;

the first corresponding relation is the corresponding relation between voltage and a first parameter, and the first parameter comprises temperature and SOC.

6. The method of claim 1, wherein the actual capacity value is determined based on a cumulative charge/discharge capacity value of the battery;

wherein the accumulated charge/discharge capacity value of the battery is any one of:

accumulated converted charge capacity value, discharge capacity value, sum of charge capacity value and discharge capacity value of the battery;

wherein the converted charge capacity value of the battery is a product of the charge capacity value of the battery and a conversion coefficient corresponding to the charge temperature of the battery;

the converted discharge capacity value of the battery is the product of the discharge capacity value of the battery and a conversion coefficient corresponding to the discharge temperature of the battery;

the conversion coefficient corresponding to the charging temperature of the battery is determined based on the charging temperature of the battery and a preset corresponding relation between the temperature and the conversion coefficient;

and determining a conversion coefficient corresponding to the discharge temperature of the battery based on the discharge temperature of the battery and the corresponding relation between the preset temperature and the conversion coefficient.

7. The method according to claim 1, characterized in that the actual capacity value is determined on the basis of the accumulated mileage and a preset second correspondence relationship;

and the second corresponding relation is the corresponding relation between the driving mileage and the capacity.

8. The method of claim 2, wherein determining the upper chargeable capacity limit of the battery based on the actual capacity value of the battery and the accumulated mileage comprises:

determining an upper limit value of a chargeable capacity of the battery based on the actual capacity value of the battery, the accumulated driving mileage and a preset third corresponding relation;

the third corresponding relation is a corresponding relation between the first capacity and a second parameter, and the second parameter comprises the second capacity and the driving mileage.

9. The method of claim 2, wherein determining the upper chargeable capacity limit of the battery based on the actual capacity value of the battery and the accumulated mileage comprises:

determining an actual state of health (SOH) of the battery based on the actual capacity value of the battery;

and determining the chargeable capacity upper limit value of the battery according to the actual SOH and the accumulated driving mileage.

10. The method of claim 9, wherein determining an upper chargeable capacity limit for the battery based on the actual SOH and the accumulated range comprises:

determining the upper limit value of the chargeable capacity of the battery according to the actual SOH, the accumulated travel mileage and a preset fourth corresponding relation;

and the fourth corresponding relation is a corresponding relation between the capacity and a third parameter, and the third parameter comprises the driving mileage and the SOH.

11. A charge control device for a battery, the device comprising:

the first acquisition module is used for acquiring a threshold value and an initial value of a charging parameter of the battery based on the received charging request; the threshold value of the charging parameter is determined based on the actual capacity value of the battery and the accumulated driving mileage of the electric automobile;

the first control command sending module is used for sending a control command for charging the battery to charge the battery if the initial value of the charging parameter is smaller than the threshold value of the charging parameter;

the second acquisition module is used for acquiring the numerical value of the charging parameter of the battery in real time in the charging process of the battery;

and the second control command sending module is used for sending a control command for stopping charging the battery to stop charging if the acquired numerical value of the charging parameter of the battery is greater than or equal to the threshold value of the charging parameter.

12. A battery management system, the system comprising: a processor and a memory storing computer program instructions;

the processor, when executing the computer program instructions, implements a method of controlling charging of a battery as claimed in any one of claims 1 to 10.

13. A computer storage medium having stored thereon computer program instructions which, when executed by a processor, implement a method of controlling charging of a battery as claimed in any one of claims 1 to 10.

Technical Field

The invention relates to the field of new energy, in particular to a battery charging control method, a battery charging control device, a battery management system and a medium.

Background

Lithium ion batteries are widely used in the fields of electric vehicles and the like due to their advantages such as high energy density and cycle performance. However, lithium ion batteries have different aging rates under different charging or discharging conditions.

During charging, the negative electrode potential of the lithium ion battery drops. If the local potential of the negative electrode is continuously too low, lithium ions can not be diffused and embedded into the negative electrode in time after the electrons are obtained from the surface of the negative electrode, lithium dendrites on the negative electrode can be caused, even the negative electrode pierces a diaphragm to cause internal short circuit, and the aging of the battery is aggravated, and even the safety problem can be caused.

When the battery is used for a long time and reaches the quality guarantee even the design life, the battery parameters are changed after serious aging, such as impedance increase, lithium ion loss and the like, so that the safety risks of lithium precipitation, thermal runaway and the like of the battery are caused. Therefore, it is urgently needed to provide a charging method to improve the safety of the battery.

Disclosure of Invention

The embodiment of the invention provides a battery charging control method, a battery charging control device, a battery management system and a medium, and improves the use safety of a battery.

In a first aspect, an embodiment of the present invention provides a method for controlling charging of a battery, including:

acquiring a threshold value and an initial value of a charging parameter of the battery based on the received charging request; the threshold value of the charging parameter is determined based on the actual capacity value of the battery and the accumulated driving mileage of the electric automobile;

if the initial value of the charging parameter is smaller than the threshold value of the charging parameter, sending a control command for charging the battery so as to charge the battery;

acquiring the numerical value of the charging parameter of the battery in real time in the charging process of the battery;

and if the acquired numerical value of the charging parameter of the battery is larger than or equal to the threshold value of the charging parameter, sending a control command for stopping charging the battery so as to stop charging.

In a second aspect, an embodiment of the present invention provides a charging control apparatus for a battery, including:

the first acquisition module is used for acquiring a threshold value and an initial value of a charging parameter of the battery based on the received charging request; the threshold value of the charging parameter is determined based on the actual capacity value of the battery and the accumulated driving mileage of the electric automobile;

the first control command sending module is used for sending a control command for charging the battery to charge the battery if the initial value of the charging parameter is smaller than the threshold value of the charging parameter;

the second acquisition module is used for acquiring the numerical value of the charging parameter of the battery in real time in the charging process of the battery;

and the second control command sending module is used for sending a control command for stopping charging the battery to stop charging if the acquired numerical value of the charging parameter of the battery is greater than or equal to the threshold value of the charging parameter.

In a third aspect, an embodiment of the present invention provides a battery management system, including: a processor and a memory storing computer program instructions;

the processor, when executing the computer program instructions, implements the method of controlling charging of a battery as provided by embodiments of the present invention.

In a fourth aspect, an embodiment of the present invention provides a computer storage medium, on which computer program instructions are stored, and when the computer program instructions are executed by a processor, the method for controlling charging of a battery according to an embodiment of the present invention is implemented.

According to the battery charging control method, the battery charging control device, the battery management system and the medium, the threshold value of the charging parameter of the battery is dynamically determined according to the actual capacity value of the battery and the accumulated driving mileage of the electric vehicle where the battery is located, so that the threshold value of the charging parameter is dynamically calculated according to the aging state of the battery. And in the process of charging the battery, if the acquired value of the charging parameter of the battery is larger than the threshold value of the newly calculated charging parameter, stopping charging the battery. The threshold value of the charging parameter of the battery is determined by considering the aging state of the battery, so that the situations of overcharge, thermal runaway and the like can be prevented when the battery is in the aging state, and the use safety of the battery is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments of the present invention will be briefly described below, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic flow chart illustrating a method for controlling charging of a battery according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram illustrating a charge control device for a battery according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a battery management system according to an embodiment of the present invention.

Detailed Description

Features and exemplary embodiments of various aspects of the present invention will be described in detail below, and in order to make objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not to be construed as limiting the invention. It will be apparent to one skilled in the art that the present invention may be practiced without some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the present invention by illustrating examples of the present invention.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

Currently, in the process of charging a battery, it is usually determined whether to stop charging the battery according to whether a charging parameter reaches a preset fixed upper limit. If the battery is still determined to stop charging by using the fixed upper limit of the charging parameter under the condition that the electric vehicle is in the extended service, the battery may have safety risks such as overcharge or thermal runaway.

Based on this, the embodiment of the present invention provides a method for controlling charging of a battery, which dynamically determines a threshold of a charging parameter of the battery according to an actual capacity value of the battery and an accumulated driving range of an electric vehicle in which the battery is located, so as to dynamically calculate the threshold of the charging parameter according to an aging state of the battery. And in the process of charging the battery, if the acquired value of the charging parameter of the battery is larger than the threshold value of the newly calculated charging parameter, stopping charging the battery. The threshold value of the charging parameter of the battery is determined by considering the aging state of the battery, so that the situations of overcharge, thermal runaway and the like can be prevented when the battery is in the aging state, and the use safety of the battery is improved.

Fig. 1 is a flowchart illustrating a method 100 for controlling charging of a battery according to an embodiment of the present invention. As shown in fig. 1, the charge control method 100 of the battery includes the steps of:

and S110, acquiring a threshold value and an initial value of a charging parameter of the battery based on the received charging request. The threshold value of the charging parameter is determined based on the actual capacity value of the battery and the accumulated driving distance of the electric vehicle in which the battery is located.

In some embodiments of the invention, the actual capacity value of the battery is a parameter used to characterize the state of aging of the battery. In some embodiments, the actual capacity value of the battery may be determined based on the accumulated charge/discharge capacity value of the battery.

As an example, the accumulated charge/discharge capacity value of the battery may be any one of the following values: the sum of the accumulated charge capacity value of the battery per charge and the back charge capacity of the battery, the accumulated discharge capacity value of the battery per discharge, the accumulated charge capacity value of the battery per charge and the accumulated discharge capacity value of the battery per discharge.

The charge capacity of the battery refers to a capacity value of battery charge measured under a predetermined condition, and the discharge capacity of the battery refers to a capacity value of battery output measured under a predetermined condition.

In some embodiments of the present invention, in order to improve the accuracy of the integration of the accumulated charge/discharge capacity value of the battery, the accumulated charge/discharge capacity value of the battery may be any one of the following values: the sum of the accumulated converted charge capacity value of the battery cell, the accumulated converted discharge capacity value of the battery cell, the accumulated converted charge capacity value of the battery cell, and the accumulated converted discharge capacity value of the battery cell.

The conversion coefficient corresponding to the charging temperature of the battery is determined based on the charging temperature of the battery and the corresponding relation between the preset temperature and the conversion coefficient, and the conversion coefficient corresponding to the discharging temperature of the battery is determined based on the discharging temperature of the battery and the corresponding relation between the preset temperature and the conversion coefficient.

That is, the charging temperature of the battery is acquired in each charging process of the battery. And then matching the charging temperature of the battery with the temperature in the corresponding relation between the preset temperature and the conversion coefficient, and taking the conversion coefficient corresponding to the temperature matched with the charging temperature of the battery in the corresponding relation as the conversion coefficient corresponding to the charging temperature of the battery.

Similarly, the discharge temperature of the battery is acquired during each discharge of the battery. And then matching the discharge temperature of the battery with the temperature in the corresponding relation between the preset temperature and the conversion coefficient, and taking the conversion coefficient corresponding to the temperature matched with the discharge temperature of the battery in the corresponding relation as the conversion coefficient corresponding to the discharge temperature of the battery.

Since the discharge temperature of the battery affects the discharge capacity of the battery, and the charge temperature of the battery affects the charge capacity of the battery, in order to improve the accuracy of integrating the integrated charge/discharge capacity value of the battery, the integrated charge/discharge capacity value of the battery can be calculated by using the charge capacity and/or discharge capacity of the battery after temperature conversion.

As a specific example, the battery management system may determine the actual capacity value of the battery based on a correspondence relationship between the pre-calibrated charge/discharge capacity and the actual capacity, and the obtained accumulated charge/discharge capacity value of the battery.

It should be noted that the statistical manner of the charge/discharge capacity in the correspondence relationship between the pre-calibrated charge/discharge capacity and the actual capacity is the same as the statistical manner of the accumulated charge/discharge capacity value of the battery.

As an example, if the accumulated charge/discharge capacity value of the battery is a sum of the accumulated charge capacity and the recharge capacity of the battery per charge, the correspondence relationship between the pre-calibrated charge/discharge capacity and the actual capacity is the correspondence relationship between the charge capacity and the actual capacity.

If the accumulated charge/discharge capacity value of the battery is the accumulated discharge capacity of the battery during each discharge, the corresponding relation between the pre-calibrated charge/discharge capacity and the actual capacity is the corresponding relation between the discharge capacity and the actual capacity.

If the accumulated charge/discharge capacity value of the battery is the sum of the accumulated discharge capacity value of the battery in each discharge and the accumulated charge capacity value of the battery in each charge, the corresponding relationship between the pre-calibrated charge/discharge capacity and the actual capacity is the corresponding relationship between the charge/discharge capacity and the actual capacity.

Table 1 shows a schematic diagram of a corresponding relationship between a pre-calibrated charge/discharge capacity and an actual capacity provided in an embodiment of the present invention.

TABLE 1

Charge/discharge capacity/Ah	Actual capacity/Ah
		A1	D1
A2	D2
		A3	D3
A4	D4

Wherein Ai is different charge/discharge capacity values, Di is different actual capacity values, and i is an integer greater than or equal to 1 and less than or equal to 4. It should be noted that the numbers of the charge/discharge capacities in table 1 are merely illustrative, and the numbers of the charge/discharge capacities in the first correspondence relationship may be adjusted according to actual needs.

In the corresponding relationship between the pre-calibrated charge/discharge capacity and the actual capacity, the actual capacity shows a decreasing trend with the increase of the charge/discharge capacity, that is, with the increase of the charge and discharge times of the battery. For the corresponding relationship in table 1, offline calibration can be performed in advance according to the charge/discharge capacity data and the actual capacity value of the history record.

In the embodiment of the invention, after the battery management system acquires the accumulated charge/discharge capacity value of the battery, the accumulated charge/discharge capacity value of the battery is matched with each charge/discharge capacity in the corresponding relation between the pre-calibrated charge/discharge capacity and the actual capacity to obtain the charge/discharge capacity matched with the accumulated charge/discharge capacity value of the battery in the corresponding relation, and the actual capacity corresponding to the charge/discharge capacity is taken as the actual capacity value of the battery.

The actual capacity value of the battery can be quickly obtained by utilizing the corresponding relation between the preset charging/discharging capacity and the actual capacity, and the calculation efficiency of the threshold value of the charging parameter is improved.

When the accumulated charge/discharge capacity value of the battery is calculated using the charge capacity and/or discharge capacity converted from the temperature, the charge/discharge capacity in the correspondence relationship between the charge/discharge capacity and the actual capacity that is calibrated in advance is also the capacity converted from the temperature.

In some embodiments of the present invention, the actual capacity value of the battery may also be determined based on the accumulated mileage of the electric vehicle and a preset second corresponding relationship between the mileage and the capacity. For example, the battery management system matches the accumulated driving mileage of the electric vehicle with each driving mileage in a preset second corresponding relationship to obtain the driving mileage matched with the accumulated driving mileage of the electric vehicle in the second corresponding relationship. And then the battery management system takes the capacity corresponding to the driving mileage matched with the accumulated driving mileage of the electric automobile in the preset second corresponding relation as the actual capacity value of the battery. The method for acquiring the actual capacity of the battery is not limited herein.

In the embodiment of the present invention, the charge control method of the battery may be applied to a battery management system. If the electric automobile needs to be charged, the electric automobile needs to be connected with the charging pile. After charging pile and electric automobile are connected, charging pile can send the charging request to battery management system to the request charges to the group battery in the electric automobile.

After receiving the charging request, the battery management system acquires a threshold value and an initial value of a charging parameter of the battery.

In the embodiment of the present invention, the initial value of the charging parameter of the battery refers to the value of the charging parameter of the battery acquired for the first time after the battery management system receives the charging request.

In an embodiment of the present invention, the charging parameter may be at least one of a State of Charge (SOC) and a charging voltage. The charging voltage of the battery is the voltage difference between the collected voltages of the two ends of the battery. The SOC of the battery is calculated in real time by an SOC calculation module in the battery management system, and the specific calculation method is not limited herein.

In the embodiment of the invention, the threshold value of the charging parameter is calculated in real time by the battery management system in consideration of the fact that the aging state of the battery is continuously changed along with the increase of the service time of the electric automobile. As one example, the battery management system calculates the threshold value of the charging parameter once every preset time interval. And when the battery management system receives the charging request, acquiring the threshold value of the charging parameter which is calculated newly.

And S120, if the initial value of the charging parameter is smaller than the threshold value of the charging parameter, sending a control command for charging the battery so as to charge the battery.

In the embodiment of the invention, if the initial value of the charging parameter is greater than or equal to the threshold value of the charging parameter, the battery management system sends a non-charging control command to the charging pile so as to improve the use safety of the battery and prevent the problems of overcharge, thermal runaway and the like.

If the initial value of the charging parameter is smaller than the threshold value of the charging parameter, the charging parameter represents that the battery can be charged, and the battery management system sends a control instruction for charging the battery to the charging pile. And after receiving a control instruction for charging the battery, the charging pile starts to charge the battery.

And S130, acquiring the numerical value of the charging parameter of the battery in real time in the charging process of the battery.

And S140, if the acquired value of the charging parameter of the battery is greater than or equal to the threshold value of the charging parameter, sending a control command for stopping charging the battery to stop charging.

In the charging process of the battery, the battery management system acquires the numerical value of the charging parameter in real time, and judges whether the acquired numerical value of the charging parameter of the battery is larger than or equal to the threshold value of the charging parameter every time the numerical value of the charging parameter of one battery is acquired.

If the acquired value of the charging parameter of the battery is smaller than the threshold value of the charging parameter, the battery management system does not act, and the charging pile can continue to charge the battery.

And if the acquired value of the charging parameter of the battery is larger than or equal to the threshold value of the charging parameter, the battery management system sends a control instruction for stopping charging the battery to the charging pile. And after receiving a control instruction for stopping charging the battery, which is sent by the battery management system, the charging pile stops charging the battery.

In the embodiment of the invention, the threshold value of the charging parameter of the battery is dynamically determined instead of fixing the upper limit of the charging parameter according to the aging state of the battery, namely the actual capacity value of the battery and the accumulated driving mileage of the electric vehicle in which the battery is positioned, so that the current aging state of the battery is fully considered, and the use safety of the battery can be improved.

It is worth mentioning that, in some embodiments, as the severity of the aging state of the battery increases, the charging capacity of the battery may be reduced by reducing the threshold of the charging parameter, so as to extend the safe life of the battery and improve the safety of the battery. That is, the threshold value of the charging parameter is gradually decreased as the actual capacity value of the battery and the driving range of the electric vehicle increase.

In an embodiment of the present invention, the battery management system calculates the threshold value of the charging parameter in real time before S110. The specific calculation method of the threshold value of the charging parameter of the battery is described in detail below.

In an embodiment of the present invention, before S110, the method includes:

s101, determining the upper limit value of the chargeable capacity of the battery based on the actual capacity value and the accumulated travel mileage of the battery.

In some embodiments of the invention, S101 comprises the steps of:

and A1, determining the chargeable capacity upper limit value of the battery based on the actual capacity value, the accumulated mileage and a preset third corresponding relation of the battery. The third corresponding relation is a corresponding relation between the first capacity and a second parameter, and the second parameter comprises the second capacity and the driving mileage.

In the embodiment of the present invention, the battery management system matches the actual capacity value of the battery with each second capacity in a preset third correspondence, to obtain the second capacity that matches the actual capacity value of the battery in the correspondence.

And the battery management system matches the accumulated driving mileage of the electric automobile with each driving mileage in a preset third corresponding relation to obtain the driving mileage matched with the accumulated driving mileage of the electric automobile in the corresponding relation.

Finally, the battery management system uses the second capacity matching the actual capacity value of the battery in the third correspondence relationship and the first capacity corresponding to the mileage matching the accumulated mileage of the electric vehicle as the chargeable capacity upper limit value of the battery.

In the preset third corresponding relation, under the condition that the second capacity is constant, if the driving mileage is higher, the corresponding first capacity is smaller. In the third correspondence relationship, when the driving range is constant, the lower the second capacity is, the smaller the corresponding first capacity is. That is, as the battery is gradually deteriorated, the upper limit of the chargeable capacity of the battery may be lowered, thereby preventing the overcharge of the battery and improving the safety of the use of the battery.

In some embodiments of the present invention, in order to improve the applicability of the method for controlling the charging of a battery provided by the embodiments of the present invention, considering that the specifications of the battery may be different, S101 includes the steps of:

a2, determining the State Of Health (SOH) SOH Of the battery based on the actual capacity value Of the battery.

In an embodiment of the invention, the actual SOH of the battery may be derived based on the actual capacity value of the battery and the nominal capacity of the battery. The ratio of the actual capacity value of the battery to the nominal capacity of the battery is the actual SOH of the battery.

A3, determining the chargeable capacity upper limit value of the battery according to the actual SOH and the accumulated mileage.

In some embodiments of the present invention, the upper chargeable capacity limit value of the battery may be determined according to the actual SOH of the battery, the driving mileage of the electric vehicle, and the preset fourth correspondence relationship. And the fourth corresponding relation is a corresponding relation between the capacity and a third parameter, and the third parameter comprises the driving mileage and the SOH. Table 2 shows a preset fourth corresponding relationship provided in an embodiment of the present invention, that is, a schematic diagram of a corresponding relationship between capacity and mileage c and SOH.

TABLE 2

Wherein, the corresponding relation between the capacity and the driving mileage c and the SOH can be obtained by the offline calibration test. As shown in Table 2, each value or range of values in row 1 of Table 2 represents a different mileage, column 1 of Table 2B_tRepresenting different SOH. Wherein t is an integer of 1 or more and 4 or less. Ejk represents a capacity value, j is an integer greater than or equal to 0, and k is an integer greater than or equal to 1. I.e. for any SOH, and any c, both correspond to a capacity value. Note that the number of SOHs and the number of miles driven in table 2 are merely illustrative, and the number of SOHs and the number of miles driven in the fourth correspondence relationship may be adjusted according to actual needs.

In the preset fourth corresponding relationship, if the SOH is constant, the corresponding capacity value is smaller as the mileage is higher. In the preset fourth corresponding relationship, if the driving range is constant, the lower the SOH is, the smaller the corresponding capacity value is. That is, as the battery is gradually deteriorated, the upper limit of the chargeable capacity of the battery may be lowered, thereby preventing the overcharge of the battery and improving the safety of the use of the battery.

In other embodiments, in the preset fourth corresponding relationship, the driving distance c may correspond to a distance segment.

In the embodiment of the present invention, the obtained actual SOH is matched with each SOH in the fourth correspondence in table 2, and the SOH in the correspondence that matches the actual SOH of the battery is found. As an example, if the absolute value of the difference between the actual SOH of the battery and a certain SOH in the corresponding relationship is less than or equal to a preset SOH difference threshold, the actual SOH of the battery may be considered to match the SOH in the corresponding relationship.

Then, the acquired accumulated mileage of the electric vehicle is matched with each mileage in the fourth correspondence relationship in the meter 2.

In one example, if each of the mileage in the fourth correspondence relationship in table 2 is one mileage section, the mileage section into which the accumulated mileage of the electric vehicle falls is taken as the mileage matching therewith. As shown in table 2, when the accumulated driving range of the electric vehicle is 5000km at S1 of 10000km, the driving range matching the accumulated driving range of the electric vehicle in table 2 is a range less than S1.

In another example, if each of the mileage in the fourth correspondence relationship in table 2 is a specific mileage value, the mileage in the correspondence relationship where the absolute value of the difference from the accumulated mileage of the electric vehicle is smaller than the preset mileage difference threshold value is taken as the mileage matching the accumulated mileage of the electric vehicle.

In yet another example, if each mileage in the fourth correspondence relationship in table 2 is a specific mileage value, the two mileage values before and after the closest to the accumulated mileage of the electric vehicle in the correspondence relationship are taken as the mileage matching the accumulated mileage of the electric vehicle. For example, if the S2 is 20000km and the S3 is 30000km, and if the integrated mileage of the electric vehicle is 25000km, the S2 and the S3 are mileage matching the integrated mileage of the electric vehicle.

Finally, the chargeable capacity upper limit value of the battery is obtained based on the SOH matching the actual SOH of the battery and the capacity value corresponding to the mileage matching the accumulated mileage of the electric vehicle in the fourth correspondence relationship in table 2.

In some embodiments of the present invention, if the mileage matching the accumulated mileage of the electric vehicle is one mileage value or one mileage segment, a capacity value corresponding to both the mileage matching the accumulated mileage of the electric vehicle and the SOH matching the actual SOH of the battery is used as the chargeable capacity upper limit value of the battery.

In some embodiments of the present invention, if the mileage matching the accumulated mileage of the electric vehicle is two mileage values before and after the nearest mileage value adjacent to the mileage value, the chargeable capacity upper limit value of the battery is calculated based on the two mileage values and two capacity values respectively corresponding to the two mileage values together with the SOH matching the actual SOH of the battery.

As one example, if the accumulated driving range S0 of the electric vehicle is greater than S2 and less than S3, the driving ranges matched with the accumulated driving range S0 of the electric vehicle are S2 and S3. If the SOH in table 2 matches the actual SOH of the battery is 90%. Then the capacity value for S2 and 90% together in table 2 is E23 and the capacity value for S3 and 90% together in table 2 is E33. The chargeable capacity upper limit value C0 of the battery may be calculated based on the following equation:

it should be noted that, in the preset corresponding relationship between the first capacity, the second capacity and the mileage, the mileage may be one value or one mileage segment. If the mileage matching the accumulated driving mileage of the electric vehicle is two mileage values in the vicinity of the nearest mileage value, the chargeable capacity upper limit value of the battery is calculated based on the two mileage values and two first capacity values corresponding to the two mileage values and a second capacity value matching the actual capacity value of the battery. For a specific calculation method, the formula (1) can be referred to, and details are not repeated here.

And S103, determining a threshold value of the charging parameter of the battery based on the actual capacity value of the battery and the chargeable capacity upper limit value of the battery.

In some embodiments of the invention, the charging parameter is a charging SOC, and accordingly, the threshold value of the charging parameter comprises a charging SOC threshold value.

Wherein, S103 includes:

s1301, the ratio of the chargeable capacity upper limit value to the actual capacity value is used as the charging SOC threshold value of the battery.

And sending a control command for stopping charging the battery to stop charging the battery under the condition that the acquired charging SOC of the battery is greater than or equal to the charging SOC threshold value, so that the safety of the battery is improved.

In some embodiments of the invention, the threshold value of the charge SOC is in the range of [ 30%, 100% ].

In other embodiments of the present invention, the charging parameter is a charging voltage, and accordingly, the threshold value of the charging parameter comprises a charging voltage threshold value.

In this case, step S103 includes not only S1301 but also S1303.

And S1303, determining a charging voltage threshold of the battery based on the charging SOC threshold, the acquired current temperature of the battery and the first corresponding relation. The first corresponding relation is the corresponding relation between voltage and a first parameter, and the first parameter comprises temperature and SOC.

Wherein the first correspondence may be obtained by a battery offline calibration test at normal charging.

As an example, table 3 shows a schematic diagram of a preset first corresponding relationship provided in an embodiment of the present invention.

TABLE 3

As shown in Table 3, C in line 1 of Table 3_qQ is an integer of 1 to 4 inclusive. T in column 1 of Table 3_pRepresents different temperatures, and p is an integer of 1 or more and 5 or less. . A in Table 3_hRepresenting different voltage values, and h is an integer greater than or equal to 1. For any one SOC, and for any one temperature, both correspond to a voltage value. Note that the number of SOCs and the number of temperatures in table 3 are merely illustrative, and the number of SOCs and the number of temperatures in the first correspondence relationship may be adjusted according to actual needs.

In the first corresponding relation, if the temperature is constant, the voltage shows a gradual reduction trend along with the reduction of the SOC, so that the charging cut-off voltage of the battery is reduced along with the serious aging degree, and the use safety of the battery is improved.

As an example, if the battery is a high nickel ternary lithium ion battery positive electrode material (NCM) battery, the range of each voltage value in table 3 is [3.6V, 4.3V ].

After the charging SOC threshold of the battery is obtained, the charging SOC threshold is matched with each SOC in the correspondence in table 3, and the SOC matched with the charging SOC threshold in the correspondence in table 3 is found. As one example, in the preset first correspondence relationship, an SOC whose absolute value of the difference from the charging SOC threshold value is equal to or less than a preset SOC threshold value may be an SOC that matches the charging SOC threshold value.

After the current temperature of the battery is obtained, the current temperature of the battery is matched with each temperature in the corresponding relation in the target 3, and the temperature matched with the current temperature of the battery in the corresponding relation in the table 3 is searched. As an example, in the preset first corresponding relationship, a temperature having a difference with the current temperature of the battery less than or equal to a preset temperature threshold may be a temperature matching the current temperature of the battery.

Next, the voltage value corresponding to the temperature matching the current temperature of the battery and the SOC matching the charging SOC threshold value in table 3 is collectively set as the charging cutoff voltage of the battery.

And sending a control command for stopping charging the battery under the condition that the acquired charging voltage of the battery is greater than or equal to the charging voltage threshold value, so as to improve the use safety of the battery and prolong the service life of the battery.

In still other embodiments of the present invention, the charging parameter comprises a charging voltage and a charging SOC, and accordingly, the threshold value of the charging parameter comprises a charging SOC threshold value and a charging voltage threshold value.

In this case, S103 also includes S1031 to S1303, and specific implementation manners can be referred to above, and are not described herein again.

In the application scenario, when the acquired charging voltage of the battery is greater than or equal to the charging voltage threshold and the acquired charging SOC is greater than or equal to the charging SOC threshold, a control command for stopping charging the battery is sent, so as to improve the use safety of the battery and prolong the service life of the battery.

The following describes a specific implementation process of the battery charging control method provided by the embodiment of the present invention, taking a battery with a nominal capacity of 100Ah and a quality guarantee of 30 kilometers of operating vehicles in 3 years as an example.

If the accumulated charging capacity of the battery from the factory to the present is 150000Ah, the actual capacity value of the battery can be determined to be 70Ah according to the corresponding relationship between the preset charging capacity and the actual capacity. Based on the actual capacity value of the battery and the nominal capacity of the battery, it can be found that the actual SOH of the battery is 70%.

If the accumulated travel distance of the electric vehicle is 35 kilometers, the upper limit value of the chargeable capacity of the battery can be determined to be 55Ah according to the corresponding relation between the preset capacity value and the travel distance and the SOH.

The SOC threshold value of the battery may be calculated to be 55Ah/70Ah 78.6% based on the actual SOH of the battery and the chargeable capacity upper limit value of the battery.

Further, according to the charging SOC threshold value of the battery, the current temperature of the battery, and the preset first corresponding relationship, the charging voltage threshold value of the battery may be determined to be 3.9V.

During the charging process of the battery, if the SOC calculated by the SOC module reaches the charging SOC threshold value of 78.6 percent and/or the voltage of the battery reaches 3.9V, the charging of the battery is stopped.

In the embodiment of the present invention, as the aging state of the battery becomes more severe from the time of shipment of the battery to the final life of the battery, in order to improve the use safety of the battery, the SOC threshold value of the battery is gradually lowered, and the charge cut-off voltage of the battery is also gradually lowered.

Fig. 2 is a schematic structural diagram illustrating a charging control apparatus for a battery according to an embodiment of the present invention. As shown in fig. 2, the charge control device 200 for a battery includes:

a first obtaining module 210, configured to obtain a threshold and an initial value of a charging parameter of the battery based on the received charging request. The threshold value of the charging parameter is determined based on the actual capacity value of the battery and the accumulated driving distance of the electric vehicle.

The first control command sending module 220 is configured to send a control command for charging the battery to charge the battery if the initial value of the charging parameter is smaller than the threshold of the charging parameter.

The second obtaining module 230 is configured to obtain the value of the charging parameter of the battery in real time during the charging process of the battery.

A second control command sending module 240, configured to send a control command to stop charging the battery if the obtained value of the charging parameter of the battery is greater than the threshold of the charging parameter, so as to stop charging.

In an embodiment of the present invention, the charging control device 200 for a battery further includes:

and the chargeable capacity upper limit value determining module is used for determining the chargeable capacity upper limit value of the battery based on the actual capacity value and the accumulated driving mileage of the battery.

And the charging parameter threshold value determining module is used for determining the threshold value of the charging parameter based on the actual capacity value and the chargeable capacity upper limit value.

In an embodiment of the present invention, the charging parameter is a charging state of charge SOC, and accordingly, the threshold of the charging parameter includes a charging SOC threshold, the charging parameter threshold determining module is configured to: the ratio of the chargeable capacity upper limit value to the actual capacity value is used as the charging SOC threshold value of the battery.

In an embodiment of the present invention, the charging parameter is a charging voltage, and accordingly, the threshold of the charging parameter includes a charging voltage threshold, the charging parameter threshold determining module is configured to:

taking the ratio of the upper limit value of the chargeable capacity to the actual capacity value as a charging SOC threshold value of the battery;

and determining a charging voltage threshold value of the battery based on the charging SOC threshold value, the acquired current temperature of the battery and a preset first corresponding relation.

The first corresponding relation is the corresponding relation between voltage and a first parameter, and the first parameter comprises temperature and SOC.

In an embodiment of the present invention, the charging parameter includes a charging voltage and a charging SOC, and accordingly, the threshold of the charging parameter includes a charging SOC threshold and a charging voltage threshold, the charging parameter threshold determining module is configured to:

taking the ratio of the upper limit value of the chargeable capacity to the actual capacity value as a charging SOC threshold value of the battery;

and determining a charging voltage threshold value of the battery based on the charging SOC threshold value, the acquired current temperature of the battery and a preset first corresponding relation.

The first corresponding relation is the corresponding relation between voltage and a first parameter, and the first parameter comprises temperature and SOC.

In an embodiment of the present invention, the actual capacity value is determined based on an accumulated charge/discharge capacity value of the battery.

Wherein the accumulated charge/discharge capacity value of the battery is any one of the following values:

the accumulated converted charging capacity value, discharging capacity value, and sum of the charging capacity value and the discharging capacity value of the battery;

the converted charging capacity value of the battery is the product of the charging capacity value of the battery and a conversion coefficient corresponding to the charging temperature of the battery, and the converted discharging capacity value of the battery is the product of the discharging capacity value of the battery and the conversion coefficient corresponding to the discharging temperature of the battery;

the conversion coefficient corresponding to the charging temperature of the battery is determined based on the charging temperature of the battery and the corresponding relation between the preset temperature and the conversion coefficient, and the conversion coefficient corresponding to the discharging temperature of the battery is determined based on the discharging temperature of the battery and the corresponding relation between the preset temperature and the conversion coefficient.

In the embodiment of the present invention, the actual capacity value is determined based on the accumulated mileage and the preset second correspondence relationship. And the second corresponding relation is the corresponding relation between the driving mileage and the capacity.

In an embodiment of the present invention, a capacity upper limit determination module may be included, configured to:

and determining the upper limit value of the chargeable capacity of the battery based on the actual capacity value of the battery, the accumulated driving mileage and a preset third corresponding relation. The third corresponding relation is a corresponding relation between the first capacity and a second parameter, and the second parameter comprises the second capacity and the driving mileage.

In an embodiment of the present invention, the capacity upper limit determining module may include:

and an actual SOH determination unit for determining an actual state of health SOH of the battery based on the actual capacity value of the battery.

And the chargeable capacity upper limit value determining unit is used for determining the chargeable capacity upper limit value of the battery according to the actual SOH and the accumulated travel mileage.

In an embodiment of the present invention, a capacity upper limit value determining unit may be filled with:

and determining the upper limit value of the chargeable capacity of the battery according to the actual SOH, the accumulated travel mileage and a preset fourth corresponding relation. And the fourth corresponding relation is a corresponding relation between the capacity and a third parameter, and the third parameter comprises the driving mileage and the SOH.

In the embodiment of the invention, the threshold value of the charging parameter of the battery is dynamically determined according to the actual capacity value of the battery and the accumulated driving distance of the electric automobile in which the battery is positioned, so that the threshold value of the charging parameter is dynamically calculated according to the aging state of the battery. And in the process of charging the battery, if the acquired value of the charging parameter of the battery is larger than the threshold value of the charging parameter calculated according to the latest calculation, stopping charging the battery. By determining the threshold value of the charging parameter of the battery in consideration of the aging state of the battery, the safety of the use of the battery is improved.

Other details of the charging control device for a battery according to the embodiment of the present invention are similar to the method according to the embodiment of the present invention described above with reference to fig. 1, and are not repeated herein.

The charge control method and apparatus of the battery according to the embodiment of the present invention described in conjunction with fig. 1 to 2 may be implemented by a battery management system of the battery. Fig. 3 is a schematic diagram illustrating a hardware structure 300 of a battery management system according to an embodiment of the invention.

As shown in fig. 3, the battery management system 300 in the present embodiment includes: the device comprises a processor 301, a memory 302, a communication interface 303 and a bus 310, wherein the processor 301, the memory 302 and the communication interface 303 are connected through the bus 310 and complete mutual communication.

In particular, the processor 301 may include a Central Processing Unit (CPU), or A Specific Integrated Circuit (ASIC), or may be configured as one or more integrated circuits implementing an embodiment of the present invention.

Memory 302 may include mass storage for data or instructions. By way of example, and not limitation, memory 302 may include an HDD, a floppy disk drive, flash memory, an optical disk, a magneto-optical disk, magnetic tape, or a Universal Serial Bus (USB) drive or a combination of two or more of these. Memory 302 may include removable or non-removable (or fixed) media, where appropriate. The memory 302 may be internal or external to the battery management system 300, where appropriate. In a particular embodiment, the memory 302 is a non-volatile solid-state memory. In a particular embodiment, the memory 302 includes Read Only Memory (ROM). Where appropriate, the ROM may be mask-programmed ROM, Programmable ROM (PROM), Erasable PROM (EPROM), Electrically Erasable PROM (EEPROM), electrically rewritable ROM (EAROM), or flash memory or a combination of two or more of these.

The communication interface 303 is mainly used for implementing communication between modules, apparatuses, units and/or devices in the embodiment of the present invention.

Bus 310 includes hardware, software, or both to couple the components of battery management system 300 to one another. By way of example, and not limitation, a bus may include an Accelerated Graphics Port (AGP) or other graphics bus, an Enhanced Industry Standard Architecture (EISA) bus, a Front Side Bus (FSB), a Hypertransport (HT) interconnect, an Industry Standard Architecture (ISA) bus, an infiniband interconnect, a Low Pin Count (LPC) bus, a memory bus, a Micro Channel Architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a Serial Advanced Technology Attachment (SATA) bus, a video electronics standards association local (VLB) bus, or other suitable bus or a combination of two or more of these. Bus 310 may include one or more buses, where appropriate. Although specific buses have been described and shown in the embodiments of the invention, any suitable buses or interconnects are contemplated by the invention.

That is, the battery management system 300 shown in fig. 3 may be implemented to include: a processor 301, a memory 302, a communication interface 303, and a bus 310. The processor 301, memory 302 and communication interface 303 are coupled by a bus 310 and communicate with each other. The memory 302 is used to store program code; the processor 301 executes a program corresponding to the executable program code by reading the executable program code stored in the memory 302 for executing the charging control method of the battery in any embodiment of the present invention, thereby implementing the charging control method and apparatus of the battery described in conjunction with fig. 1 to 2.

The embodiment of the invention also provides a computer storage medium, wherein the computer storage medium is stored with computer program instructions; the computer program instructions, when executed by a processor, implement a method for controlling charging of a battery according to an embodiment of the present invention.

It is to be understood that the invention is not limited to the specific arrangements and instrumentality described above and shown in the drawings. A detailed description of known methods is omitted herein for the sake of brevity. In the above embodiments, several specific steps are described and shown as examples. However, the method processes of the present invention are not limited to the specific steps described and illustrated, and those skilled in the art can make various changes, modifications and additions or change the order between the steps after comprehending the spirit of the present invention.

The functional blocks shown in the above structural block diagrams may be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware, it may be, for example, an electronic circuit, an Application Specific Integrated Circuit (ASIC), suitable firmware, plug-in, function card, or the like. When implemented in software, the elements of the invention are the programs or code segments used to perform the required tasks. The program or code segments may be stored in a machine-readable medium or transmitted by a data signal carried in a carrier wave over a transmission medium or a communication link. A "machine-readable medium" may include any medium that can store or transfer information. Examples of a machine-readable medium include electronic circuits, semiconductor memory devices, ROM, flash memory, Erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, fiber optic media, Radio Frequency (RF) links, and so forth. The code segments may be downloaded via computer networks such as the internet, intranet, etc.

As will be apparent to those skilled in the art, for convenience and brevity of description, the specific working processes of the systems, modules and units described above may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again. It should be understood that the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the present invention, and these modifications or substitutions should be covered within the scope of the present invention.