Battery charging method, vehicle, and storage medium

Abstract

The present disclosure relates to a battery charging method, a vehicle and a storage medium. The method comprises: when the battery is in a charging state, pausing for a target duration; and after pausing for the target duration, adjusting a charging current of the battery. The present solution can avoid lithium precipitation of the battery by pausing for the target duration and flexibly adjusting the charging current of the battery in real time.

Description

Technical Field

[0001] This disclosure relates to the field of battery technology, and more specifically, to a battery charging method, a vehicle, and a storage medium. Background Technology

[0002] With the development of technology, batteries are increasingly used in people's lives, with lithium batteries accounting for a particularly prominent proportion. Lithium-ion batteries have advantages such as high voltage, high energy density, and low environmental pollution, and are widely used in electric vehicles and various mobile devices. However, improper charging methods can lead to lithium plating in lithium-ion batteries, which greatly reduces charging efficiency. Therefore, how to achieve efficient battery charging is a technical problem that urgently needs to be solved. Summary of the Invention

[0003] In order to overcome the problems existing in the related technologies, this disclosure provides a battery charging method, a vehicle, and a storage medium.

[0004] The first aspect of this disclosure provides a battery charging method, the method comprising: The target duration of pause when the battery is charging; After pausing for the target duration, the charging current of the battery is adjusted.

[0005] Optionally, adjusting the charging current of the battery includes: When the relationship between the pause voltage difference and the change in charge satisfies the first condition, the charging current of the battery is adjusted, wherein the pause voltage difference is the voltage difference of the battery before and after the charging pause.

[0006] Optionally, the first condition includes: The curve corresponding to the pause voltage difference and the change in charge shows an inflection point, and the pause voltage difference reaches its maximum value at this inflection point; or... The first derivative of the pause voltage difference with respect to the change in charge reaches zero.

[0007] Optionally, adjusting the charging current of the battery includes: The charging current is reduced based on the voltage difference at the pause point.

[0008] Optionally, reducing the charging current based on the pause voltage difference includes: Obtain the adjustment value corresponding to the pause voltage difference; The adjusted charging current is obtained by subtracting the adjustment value from the charging current.

[0009] Optionally, obtaining the adjustment value corresponding to the pause voltage difference includes: The adjustment value corresponding to the pause voltage difference is obtained from the target mapping table, which stores the correspondence between the pause voltage difference and the adjustment value.

[0010] Optionally, the target duration of the pause includes: When the battery meets the second condition, the target duration is paused.

[0011] Optionally, the second condition includes at least one of the following: The change in charge has reached the target value; The charging time has reached the target time.

[0012] Optionally, the change in charge reaching the target value includes: The total charge change of the battery pack reaches the target value; or, The change in charge of each cell in the battery reaches the target value.

[0013] Optionally, adjusting the charging current of the battery includes: Obtain the pause voltage difference corresponding to the entire battery pack, and adjust the overall charging current of the battery pack according to the pause voltage difference; or, Obtain the pause voltage difference corresponding to each cell in the battery, and adjust the charging current of the cell according to the pause voltage difference.

[0014] Optionally, the pause target duration when the battery meets the second condition includes: When the battery meets the trigger condition and the second condition, the target duration is paused.

[0015] Optionally, the triggering condition includes at least one of the following: The first count is greater than the first target count, where the first count is the number of times the battery performs high-power charging, and the charging power of the high-power charging is greater than the target power; The second number of times is greater than the second target number of times, where the second number of times the battery is charged at a low temperature, and the temperature of the battery at the low temperature is less than the target temperature.

[0016] Optionally, the target duration is determined based on the temperature of the battery, with a higher battery temperature corresponding to a shorter target duration.

[0017] A second aspect of this disclosure provides a vehicle, the vehicle comprising: A memory on which computer programs are stored; A processor for executing the computer program in the memory to implement the steps of the method described in the first aspect.

[0018] Thirdly, this disclosure provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described in the first aspect.

[0019] This disclosure allows for a pause for a target duration during battery charging, and after the pause, the battery charging current is adjusted. By adjusting the battery charging current in a timely manner, lithium plating in the battery can be reduced. Furthermore, since the charging current is adjusted after the pause for the target duration, the battery charging efficiency can be maintained to a certain extent.

[0020] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0021] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings: Figure 1 This is an application scenario of a battery charging method disclosed in this disclosure.

[0022] Figure 2 This is a flowchart illustrating a battery charging method according to an exemplary embodiment.

[0023] Figure 3 This is an example diagram illustrating the connection between a power battery and a charging device in a battery charging method according to an exemplary embodiment.

[0024] Figure 4 This is a structural block diagram of a power battery pack in a battery charging method according to an exemplary embodiment.

[0025] Figure 5 This is an example diagram illustrating a pause voltage difference in a battery charging method according to an exemplary embodiment.

[0026] Figure 6 This is a flowchart illustrating another battery charging method according to an exemplary embodiment.

[0027] Figure 7 This is an example diagram illustrating the occurrence of lithium plating points in another battery charging method according to an exemplary embodiment.

[0028] Figure 8 This is an example diagram illustrating the determination of lithium deposition points in another battery charging method according to an exemplary embodiment.

[0029] Figure 9This is an example diagram comparing the current adjustment and MSCC charging current according to an exemplary embodiment of another battery charging method.

[0030] Figure 10 This is a flowchart illustrating an alternative battery charging method that automatically adjusts the charging current according to an exemplary embodiment.

[0031] Figure 11 This is a block diagram illustrating a battery charging device according to an exemplary embodiment.

[0032] Figure 12 This is a block diagram illustrating a vehicle according to an exemplary embodiment. Detailed Implementation

[0033] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0034] Embodiments of this disclosure will now be described in more detail with reference to the accompanying drawings. While some embodiments of this disclosure are shown in the drawings, it should be understood that this disclosure can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of this disclosure. It should be understood that the accompanying drawings and embodiments of this disclosure are for illustrative purposes only and are not intended to limit the scope of protection of this disclosure.

[0035] It should be understood that the steps described in the method embodiments of this disclosure may be performed in different orders and / or in parallel. Furthermore, the method embodiments may include additional steps and / or omit the steps shown. The scope of this disclosure is not limited in this respect.

[0036] The term "comprising" and its variations as used herein are open-ended inclusions, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". Definitions of other terms will be given in the description below.

[0037] It should be noted that the concepts of "first" and "second" mentioned in this disclosure are used only to distinguish different devices, modules or units, and are not used to limit the order of functions performed by these devices, modules or units or their interdependencies.

[0038] Lithium-ion batteries, as a core component of new energy vehicles, determine the effective driving range and play a crucial role in vehicle operation. Charging rate is one of the key indicators for evaluating battery performance. While high-power charging allows vehicles to acquire more electrical energy in a shorter time, extending their driving range, lithium plating is a primary challenge for the further development of high-power charging. During charging, some lithium ions fail to embed themselves in the graphite and accumulate in certain areas, leading to the transformation of lithium ions into lithium metal, which then appears on the graphite surface.

[0039] Here, the deposited lithium metal not only poses a certain degree of safety hazard to the battery, but also shortens its lifespan. Therefore, accurately detecting and preventing lithium plating inside the battery is crucial for its operation.

[0040] In some implementations, multi-step constant current charging (MSCC) is a constant current and constant voltage charging method that achieves more efficient battery charging by adjusting the current in stages. Specifically, it uses a high current to charge the battery to a certain voltage, and then gradually reduces the current to achieve fine control of the charging process. This method helps to minimize battery temperature rise and internal losses, extend battery life, and improve charging efficiency. However, multi-step constant current charging has problems such as poor accuracy, poor flexibility, limited application scenarios, and insufficient fast charging capability.

[0041] Figure 1 This describes an application scenario based on a battery charging method disclosed in this disclosure. For example... Figure 1 As shown, vehicle 1 is connected to charging station 2 for charging. Vehicle 1 can be an electric vehicle or an electric bicycle, or other equipment that can be charged using charging station 2; charging station 2 can be a DC charging station or an AC charging station.

[0042] Figure 2 This is a flowchart illustrating a battery charging method according to an exemplary embodiment. Please refer to [link / reference]. Figure 2 The battery charging method may include the following steps.

[0043] In step S110, when the battery is in a charging state, the target pause duration is determined.

[0044] This disclosure can be applied to vehicles, which may include a Battery Management System (BMS) and a battery, wherein the battery may be a power battery pack. For example, the power battery 12 may be a blade cell, a prismatic cell, a button cell, a pouch cell, or a cylindrical cell, etc.

[0045] A battery management controller (BMS) can include multiple designated components that can read the voltage and current signals of each cell in the battery. Additionally, the BMS can process the voltage signals of each cell in real time and adjust the current input to the battery pack.

[0046] Please see Figure 3 The vehicle may include a battery management controller 11 and a power battery pack 12. When the battery management controller 11 detects that the vehicle is connected to a charging device, it can determine whether the power battery 12 needs to be charged. If it is determined that the power battery 12 needs to be charged, the battery management controller 11 can obtain the SOC (State of Charge) and select a preset charging power according to the SOC to start the charging operation.

[0047] In determining whether the power battery 12 needs charging, this embodiment of the disclosure can determine whether the state of charge (SOC) or temperature of the power battery 12 meets the charging conditions. If the charging conditions are met, it is determined that charging is required. For example, if the SOC of the power battery 12 is below 20%, it indicates that the battery needs charging.

[0048] Furthermore, in the process of selecting the preset charging power based on the SOC, the embodiments of this disclosure can determine the charging power corresponding to the current SOC. Different SOCs may correspond to different charging powers / charging methods; that is, there is a corresponding relationship between SOC and charging power / charging method. Based on this relationship, the charging power corresponding to each SOC can be obtained. For example, when the SOC is low, the corresponding charging method is high-power charging; when the SOC is medium, the corresponding charging method is medium-power charging; when the SOC is high, the corresponding charging method is low-power charging; and when the SOC is full, the corresponding charging method is trickle charging.

[0049] In some implementations, such as Figure 4 The power battery 12 shown may include multiple battery cells 121. The battery management controller 11 can collect charging data of each battery cell 121 in the power battery pack 12 through the BIC signal (Battery Information Collection Signal). It can be seen that the BIC is used to achieve voltage sampling, temperature sampling, and current sampling of the battery cells 121. Different battery cells will have different corresponding BICs.

[0050] For example, the signal corresponding to cell 1 is BIC1, the signal corresponding to cell 2 is BIC2, and the signal corresponding to cell n is BICn. Among them, BIC1 can include the voltage, current, and temperature of cell 1; BIC2 can include the voltage, current, and temperature of cell 2; and BIC3 can include the voltage, current, and temperature of cell 3.

[0051] As an alternative approach, when it is determined that the battery is in a charging state, embodiments of this disclosure can control the battery to pause for a target duration, i.e., pause for a target charging duration. For example, when it is determined that the battery is in a charging state, it can pause for 1 second. Here, the pause can be performed periodically, such as pausing for the target duration every time the target charging duration is reached.

[0052] When it is determined that the battery is in a charging state, embodiments of this disclosure can determine whether the battery meets a second condition. If it is determined that the battery meets the second condition, a pause operation can be triggered. This pause operation can be used to control the target pause duration of the battery. Here, the second condition may include at least one of the following: the change in charge reaches a target value; the charging time reaches a target time.

[0053] Specifically, when the battery is detected to be in a charging state, this embodiment of the disclosure can determine whether the change in battery charge has reached a target value. When it is determined that the change in charge has reached the target value, a pause operation can be triggered.

[0054] In this process, the embodiments of this disclosure can monitor the changes in the battery's state of charge (SOC) in real time. That is, the embodiments of this disclosure can obtain the amount of change in battery charge during charging. This amount of change in charge can be the increase in SOC, which can be the difference between the SOC at the second time and the SOC at the first time. For example, if the SOC at the second time t2 is 21% and the SOC at the first time t1 is 20%, then the amount of change in charge is 21% - 20% = 1%.

[0055] Based on this, the embodiments of this disclosure can determine whether the change in charge has reached a target value. If the target value is reached, it is determined that the battery meets a second condition, wherein the target value can be a preset SOC. That is, the battery has a preset SOC each time it is charged, and the embodiments of this disclosure can control the target duration of the battery charging pause. For example, a charging pause operation can be performed once the battery charges 1% SOC.

[0056] In this embodiment of the disclosure, a target value can be preset in the charging program. When the change in charge is detected to reach the target value, a charging pause operation can be triggered. The duration of the charging pause can be the target duration. In other words, when the change in charge reaches the target value, a charging pause operation can be triggered, i.e., a pause for the target duration.

[0057] For example, the charging times include t1, t2, and t3. At time t1, the state of charge (SOC) is 12%, and at time t2, the SOC is 13%. It is evident that the change in charge has reached the target value of 1%, at which point a pause in charging can be performed. At time t2, the SOC is 13%, and at time t3, the SOC is 14%. It is evident that the change in charge has also reached the target value of 1%, at which point a pause in charging can also be performed. Here, performing a pause in charging reduces the output current of the charging device to zero.

[0058] Optionally, when the battery is detected to be in a charging state, embodiments of this disclosure can determine whether the battery charging time has reached a target value. If it is determined that the charging time has reached the target value, a pause operation can be triggered.

[0059] In this process, the embodiments of this disclosure can monitor the battery charging time in real time, that is, the embodiments of this disclosure can obtain the battery charging time during the charging process. Based on this, the embodiments of this disclosure can determine whether the charging time has reached the target time. If the target time has been reached, it is determined that the battery meets the second condition. In other words, for every target charging time, the embodiments of this disclosure can control the battery to pause charging for a target duration. For example, a pause charging operation can be performed once every 1 hour of charging.

[0060] In this embodiment of the disclosure, a target time can be preset in the charging program. When the charging time is detected to have reached the target time, a charging pause operation can be triggered, and the duration of the pause can be the target duration. In other words, when the charging time reaches the target time, a charging pause operation can be triggered, i.e., a pause for the target duration.

[0061] In step S120, after the target pause duration, the charging current of the battery is adjusted.

[0062] As an optional approach, after pausing the charging for the target duration, embodiments of this disclosure can obtain the corresponding pause voltage difference, which can be the voltage difference of the battery before and after the charging pause. For example, the battery voltage before the charging pause is E. e After charging is paused, the battery voltage is E. p The voltage difference during the pause is E. e -E p .

[0063] Please see Figure 5 Voltage difference during pause U p It can be the voltage value E of the battery during charging. e Subtract the voltage value E during the charging pause. p That is, the voltage difference during a pause can be the difference between two current states. Here, the voltage value E during paused charging is... pThe voltage value can be the value at the first moment of the charging pause. Because the internal polarization of the battery is reduced after the charging pause, the battery voltage value will gradually decrease. Therefore, to ensure the accuracy of the voltage difference acquisition, this embodiment can use the value at the moment the power was cut off. For example, if the change in charge is detected to reach the target value at time t2, and the charging pause operation is performed at time t3, then the voltage value at time t3 can be used as the voltage value at the moment of the charging pause.

[0064] The charging pause operation in this embodiment can be temporary, meaning that the battery can resume normal charging after the target charging duration has elapsed. The preferred pause time during charging is 1 second, meaning the target duration can be 1 second. This is mainly because a longer pause time would alleviate the battery's original polarization, causing a deviation between the charging and target charging conditions. Conversely, a shorter pause time would limit the data collection capabilities of the charging equipment and result in excessive data volume.

[0065] It should be noted that, in addition to adjusting the battery charging current based on the voltage difference during pauses, the charging current can also be adjusted based on the capacitance difference during pauses, the inductance difference during pauses, etc.

[0066] As an optional approach, after obtaining the pause voltage difference, embodiments of this disclosure can determine whether the relationship between the pause voltage difference and the change in charge meets a first condition. If so, the charging current of the battery is adjusted. Specifically, embodiments of this disclosure can reduce the charging current of the battery based on the pause voltage difference.

[0067] For example, in this embodiment of the disclosure, an adjustment value corresponding to the pause voltage difference can be obtained. Based on this, the charging current of the battery is adjusted according to the adjustment value to obtain a target charging current, that is, an adjusted charging current. Based on this, the battery is charged through the target charging current.

[0068] The aforementioned change in charge reaching the target value can include: the change in charge of the entire battery pack reaching the target value; or, the change in charge of each cell in the battery reaching the target value. In other words, embodiments of this disclosure can monitor the change in charge of the entire battery pack, and when it is determined that the change in charge of the entire pack has reached the target value, control the overall battery to pause for a target duration, i.e., each cell in the battery pauses charging for a target duration. Here, the change in charge of the entire battery pack can be the total or average value of the change in charge of all cells in the battery, etc.

[0069] Optionally, embodiments of this disclosure may also monitor the charge change of each cell in the battery separately, and when the charge change of a certain cell reaches a target value, control the pause time of that cell to be different. It is evident that the timing of triggering the charging pause differs depending on the cell type.

[0070] A battery may include multiple cells. Therefore, when obtaining the change in charge of the battery during charging, this embodiment can obtain the change in charge of each cell. Based on this, when the change in charge of each cell reaches a target value, a charging pause operation is performed. Then, the charging current of each cell before and after the charging pause operation is obtained, and the pause voltage difference corresponding to each cell is obtained accordingly. If it is determined that the pause voltage difference corresponding to the cell meets a first condition, the charging current of that cell can be adjusted.

[0071] As an example, the battery includes cell 1 and cell 2. In this embodiment, the charge change of cell 1 and cell 2 can be monitored respectively. When the charge change of cell 1 reaches the target value, this embodiment can control the charging pause of cell 1 for a target duration and obtain the voltages of cell 1 before and after the charging pause as U1 and U2 respectively. Therefore, the voltage difference of cell 1 at the pause is U1-U2. Then, the derivative of the voltage difference at the pause is calculated. If the value is 0, it means that lithium plating is about to occur in cell 1. At this time, the current adjustment value corresponding to the voltage difference at the pause can be obtained, and the charging current of cell 1 can be adjusted according to the current adjustment value to obtain the target current.

[0072] The current adjustment process of cell 2 is similar to that of cell 1. The two can be executed in parallel without interfering with each other. That is, in this embodiment of the present disclosure, when lithium plating is detected in cell 1, the charging current of cell 1 can be adjusted separately. For cell 2, which has not yet plating lithium, the charging current can be kept unchanged.

[0073] It should be noted that the target values ​​or target times for different battery cells can be the same or different, and the target durations for different battery cells can be the same or different. For example, when battery cell 1 reaches the first target value in its charge change, it can pause for the first target duration. Similarly, when battery cell 2 reaches the second target value in its charge change, it can pause for the second target duration.

[0074] In summary, the embodiments of this disclosure can adopt different charging strategies for different battery cells. That is, to address the inconsistency of battery cells, the embodiments of this disclosure can employ intelligent and appropriate charging algorithms, without relying on a fixed charging strategy preset at the factory. In addition, the embodiments of this disclosure can prevent lithium plating by detecting the lithium plating status of each battery cell, thereby extending battery life. Moreover, the lithium plating status is fed back in real time, which not only allows for intelligent current adjustment to maximize charging capacity but also ensures that lithium plating does not occur in the battery.

[0075] Optionally, before adjusting the battery charging current, embodiments of this disclosure may determine whether the relationship between the pause voltage difference and the change in charge satisfies a first condition. If the relationship between the pause voltage difference and the change in charge satisfies the first condition, the battery charging current is adjusted. Conversely, if the relationship between the pause voltage difference and the change in charge does not satisfy the first condition, the charging current is kept constant, i.e., the battery charging current is not adjusted.

[0076] Here, the first condition is used to determine whether lithium plating points have appeared in the battery. If the first condition is met, it means that lithium plating points have appeared in the battery. In this case, in order to extend the battery's life, the charging current of the battery can be adjusted.

[0077] In this embodiment of the invention, the charging process can be paused for a target duration, and the charging current of the battery can be adjusted after the target duration is paused. By adjusting the charging current of the battery in a timely manner, the occurrence of lithium plating in the battery can be reduced. Since the charging current is adjusted after the target duration is paused, the charging efficiency of the battery can be maintained to a certain extent.

[0078] Figure 6 This is a flowchart illustrating another battery charging method according to an exemplary embodiment; please refer to [link / reference]. Figure 6 The battery charging method may include the following steps.

[0079] In step S210, when the battery is in a charging state, the target pause duration is determined.

[0080] As an alternative, before performing the pause charging operation, embodiments of this disclosure may determine whether the battery meets the trigger condition. If the battery meets the trigger condition and also meets the second condition, the pause target duration is determined.

[0081] Specifically, the triggering conditions may include at least one of the following: the first count is greater than the first target count, which may be the number of times the battery performs high-power charging, and the charging power of the high-power charging is greater than the target power; the second count is greater than the second target count, which may be the number of times the battery performs charging in a low-temperature state, and the battery temperature in the low-temperature state is less than the target temperature.

[0082] As an alternative approach, in determining whether the battery meets the triggering conditions, this embodiment of the present disclosure may first obtain the first number of times the battery performs high-power charging, and then determine whether the first number is greater than the first target number. If it is determined that the first number exceeds the first target number and meets the second condition, the target duration can be paused.

[0083] Conversely, if it is determined that the first count does not exceed the first target count, then the embodiments of this disclosure may not perform the pause charging operation. High-power charging is the main cause of lithium plating problems; that is, the more times high-power charging is performed, the greater the possibility of lithium plating in the battery. In this case, performing charge change acquisition and pause charging operations can not only avoid unnecessary pause charging operations, but also ensure battery charging safety and reduce the possibility of lithium plating.

[0084] As an alternative method, in the process of determining whether the battery meets the triggering conditions, this embodiment of the disclosure can also obtain the second number of times the battery performs charging in a low-temperature state. Based on this, it can be determined whether the second number exceeds the second target number. If it is determined that the second number exceeds the second target number and meets the second condition, the target duration can be paused.

[0085] Conversely, if it is determined that the second count does not exceed the second target count, then the embodiments of this disclosure may not require interrupting the charging process. Low-temperature charging is also a major cause of lithium plating problems; that is, the more times the battery is charged at low temperatures, the greater the possibility of lithium plating. In this case, performing charge change acquisition and interrupting the charging process can not only avoid unnecessary interruptions but also ensure battery charging safety and reduce the possibility of lithium plating.

[0086] Here, the first target number of times for high-power charging and the second target number of times for low-temperature charging can be the same or different. There is no specific limit here, and the choice can be made according to the actual situation.

[0087] Optionally, the implementation of this embodiment can also be determined by combining the first count and the second count. For example, if it is determined that the first count exceeds the first target count, the second count is greater than the second target count, and the second condition is met, then the target duration can be paused.

[0088] Alternatively, before pausing for the target duration, this embodiment of the disclosure may determine whether the battery is currently in a high-power charging state. If it is determined that the battery is in a high-power charging state, this embodiment of the disclosure may perform a charging pause. Conversely, if it is determined that the battery is not in a high-power charging state, this embodiment of the disclosure may not perform a charging pause.

[0089] As described above, when the change in charge reaches the target value, or when the charging time reaches the target time, this embodiment of the present disclosure can pause for the target duration. That is, the battery can pause charging for the target duration, and charging can resume after the pause. Here, the target duration can be obtained based on empirical values ​​or determined according to the actual situation of the battery.

[0090] As an example, before performing a pause charging operation, this embodiment of the disclosure can obtain the battery temperature, and based on this, obtain the target duration corresponding to that temperature; the higher the temperature, the shorter the corresponding pause charging duration. For example, if the battery temperature is 26 degrees Celsius, the corresponding target duration can be 0.5 seconds. Or, if the battery temperature is 10 degrees Celsius, the corresponding target duration is 1 second.

[0091] As another example, before performing a pause charging operation, embodiments of this disclosure can obtain the charging power level of the battery, and based on this, obtain the target duration corresponding to the charging power level. The higher the charging power level, the shorter the corresponding pause charging duration.

[0092] In step S220, when the relationship between the pause voltage difference and the change in charge satisfies the first condition, the charging current of the battery is adjusted.

[0093] As described above, after obtaining the pause voltage difference, this embodiment of the present disclosure can determine whether the relationship between the pause voltage difference and the change in charge satisfies a first condition. If the relationship between the pause voltage difference and the change in charge satisfies the first condition, the charging current of the battery is adjusted. Here, the first condition may include: the curve corresponding to the pause voltage difference and the change in charge shows an inflection point, wherein the pause voltage difference reaches its maximum value at the inflection point; or, the first derivative of the pause voltage difference with respect to the change in charge reaches zero.

[0094] For example, this disclosure embodiment can obtain a pause voltage difference every time the change in charge reaches a target value. Therefore, by continuously monitoring the change in charge during the battery charging process, this disclosure embodiment can obtain... Figure 7 The example diagram shown is as follows. Figure 7 The middle curve can be the pause voltage difference. U p The SOC curve shows the battery's state of charge (SOC) on the horizontal axis and the voltage difference on the vertical axis. The voltage difference reaches its maximum when the SOC is 17%, and then decreases. This maximum voltage difference can be considered the point where lithium plating occurs. Figure 7 The inflection point in the figure represents the point at which lithium plating occurs at 17% SOC.

[0095] It can be seen that determining whether the relationship between the stall voltage difference and the change in charge meets the first condition can be done by determining whether the stall voltage difference has reached its maximum value. If the stall voltage difference reaches its maximum value before the SOC reaches 100%, that is, an inflection point occurs, it indicates that the battery is about to undergo lithium plating. At this time, in order to ensure the battery's lifespan, the battery's charging current can be adjusted.

[0096] Optionally, in determining whether the relationship between the pause voltage difference and the change in charge satisfies the first condition, embodiments of this disclosure may differentiate the pause voltage difference with respect to the battery's state of charge, i.e., obtain the first derivative of the pause voltage difference with respect to the change in charge, and determine whether the first derivative has a zero point. If the first derivative has a zero point, then it is determined that the second pause voltage difference satisfies the first condition.

[0097] For example, the first derivative of the pause voltage difference with respect to the change in charge can be expressed as d U p / dSOC. When d is determined U p If / dSOC is greater than 0, then it can continue to use I e Charging; when d U p / dSOC equals 0, indicating that lithium plating is about to occur in the battery. Details are as follows... Figure 8 As shown, the BMS can achieve charging by reducing the required charging current, and the adjusted charging current I = I e - I. Figure 8 The curve in the figure represents the first derivative of the stall voltage difference. U p The / dSOC-SOC curve, with its zero point indicating the occurrence of lithium plating at 17% SOC.

[0098] The main principle behind this embodiment of the invention for determining whether a battery is about to develop lithium plating points by using the voltage difference during pauses is as follows: A lithium-ion battery can be considered as an equivalent circuit. If lithium plating occurs during charging, an additional parallel path will appear at the negative electrode of the battery. This parallel path will cause a decrease in the internal resistance of the battery. Multiple tests have shown that the difference between the battery voltage during paused charging and the battery voltage during charging decreases continuously as lithium plating increases; that is, the voltage difference during pauses decreases as lithium plating increases.

[0099] In addition, because a circuit has become open, the voltage difference is interrupted. U p The SOC curve shows a clear inflection point with the appearance of lithium plating; therefore, this inflection point can be taken as the point at which lithium plating occurs. Details are as follows... Figure 7 shown The inflection point of the Up-SOC curve at 17% SOC, and Figure 8 The d shown U p The zero point of the / dSOC-SOC curve.

[0100] In other words, when lithium plating is not present in the battery, the corresponding stop voltage difference continuously increases with the increase of SOC; that is, the stop voltage difference remains rising until the SOC reaches 100%, and does not decrease. Conversely, when lithium plating occurs in the battery, the presence of parallel pathways causes the stop voltage difference to decrease as the SOC increases, indicating an inflection point. Therefore, this embodiment of the present disclosure can accurately detect whether lithium plating has occurred in the battery by monitoring the stop voltage difference.

[0101] It should be noted that, in determining whether the relationship between the stall voltage difference and the change in charge satisfies the first condition, this embodiment of the present disclosure can also determine whether the stall voltage difference exceeds a stall threshold. This stall threshold can be the average lithium deposition point obtained through multiple experiments. If the stall voltage difference is detected to exceed the stall threshold, the charging current of the battery is adjusted. For example, if the stall voltage difference is detected to exceed the voltage difference threshold, the charging current of the battery is adjusted.

[0102] As an alternative approach, during the adjustment of the battery charging current based on the voltage difference at the pause point, embodiments of this disclosure can reduce the charging current based on the voltage difference at the pause point. For example, reducing the charging current based on the voltage difference at the pause point.

[0103] Specifically, in this embodiment, the adjustment value corresponding to the pause voltage difference can be obtained, and the charging current can be subtracted from the adjustment value to obtain the adjusted charging current.

[0104] For example, in this embodiment of the disclosure, the current adjustment value corresponding to the pause voltage difference can be obtained. Based on this, the current adjustment value is subtracted from the charging current to obtain the adjusted charging current. Here, there is a corresponding relationship between the current adjustment value and the pause voltage difference, so the current adjustment value corresponding to the pause voltage difference can be obtained by searching.

[0105] In other words, embodiments of this disclosure can obtain the adjustment value corresponding to the pause voltage difference from the target mapping table, wherein the target mapping table stores the correspondence between the pause voltage difference and the adjustment value.

[0106] Optionally, in the process of obtaining the current adjustment value corresponding to the pause voltage difference, the embodiments of this disclosure may also obtain the battery temperature and charging power, and on this basis, obtain the corresponding current adjustment value based on the battery temperature, charging power and pause voltage difference.

[0107] To better illustrate the advantages of the embodiments of this disclosure, the following are now provided: Figure 9 The example diagram shown is as follows. Figure 9Curve 901 is an example curve of the charging current proposed in the embodiments of this disclosure, and curve 902 is an example curve of the MSCC charging current. By comparing curves 901 and 902, it can be seen that the embodiments of this disclosure can greatly shorten the charging time while avoiding lithium plating, that is, ensure the efficiency of battery charging.

[0108] As a specific implementation, this embodiment of the present disclosure can acquire the charging current and the pause duration (target duration) during battery charging. Here, the charging current can be determined based on the State of Charge (SOC), and the pause duration can be the duration of the charging pause, which can be preset or determined based on the actual situation of the battery (cell), such as the actual temperature of the cell. Based on this, this embodiment of the present disclosure can perform a charging pause operation every time the cell is charged to 1% SOC, and acquire the battery voltage before and after the charging pause, so as to determine the pause voltage difference based on these two voltages. Then, the first derivative of this pause voltage difference is calculated to determine d. Is U / dSOC about to reach zero?

[0109] If we determine d If U / dSOC is about to reach zero, it indicates that lithium plating is imminent in the battery cell. At this point, the current adjustment value can be obtained. I, and adjust the battery charging current according to this current adjustment value to obtain the target charging current, then charge the corresponding cell using the target charging current. Conversely, if d is determined... If U / dSOC has not reached zero, the embodiments of this disclosure can continue to charge with the original current.

[0110] The battery charging method described above enables the battery pack to meet the charging strategy of the lithium plating limit. Since none of the cells in the battery have reached the lithium plating point, the battery life can be greatly improved.

[0111] In summary, the embodiments of this disclosure can maximize the charging capacity by automatically finding the ideal charging curve for each battery pack, which can meet people's needs. Moreover, the pause voltage difference also has a certain physical meaning, that is, it can characterize the degree of lithium plating aging of the battery. Therefore, by monitoring the pause voltage difference, the battery life can be extended.

[0112] In this embodiment of the invention, the change in battery charge is acquired during battery charging. When the change in charge is at a target value, charging is paused. Based on this, the voltage difference between the battery before and after the charging pause is acquired. If it is determined that the relationship between the voltage difference and the change in charge satisfies a first condition, the charging current of the battery is adjusted. Since the relationship between the voltage difference and the change in charge satisfies the first condition, it indicates that lithium plating is about to occur in the battery. At this time, timely adjustment of the battery current can reduce the occurrence of lithium plating. Furthermore, since the charging current is adjusted according to the voltage difference, the charging efficiency of the battery can be maintained to a certain extent.

[0113] Figure 11 This is a block diagram illustrating a battery charging device according to an exemplary embodiment, such as... Figure 11 The battery charging device 300 shown may include a pause module 310 and an adjustment module 320.

[0114] The pause module 310 is configured to pause for a target duration when the battery is in a charging state. The adjustment module 320 is configured to adjust the charging current of the battery after pausing for the target duration.

[0115] In some embodiments, the adjustment module 320 is further configured to adjust the charging current of the battery when the relationship between the pause voltage difference and the change in charge satisfies a first condition, wherein the pause voltage difference is the voltage difference of the battery before and after the charging pause.

[0116] In some implementations, the first condition includes: The curve corresponding to the pause voltage difference and the change in charge shows an inflection point, and the pause voltage difference reaches its maximum value at this inflection point; or... The first derivative of the pause voltage difference with respect to the change in charge reaches zero.

[0117] In some implementations, the adjustment module 320 is also configured to reduce the charging current based on the pause voltage difference.

[0118] In some implementations, the adjustment module 320 is further configured to obtain an adjustment value corresponding to the pause voltage difference; and subtract the adjustment value from the charging current to obtain the adjusted charging current.

[0119] In some implementations, the adjustment module 320 is further configured to obtain the adjustment value corresponding to the pause voltage difference from a target mapping table, the target mapping table storing the correspondence between the pause voltage difference and the adjustment value.

[0120] In some implementations, the pause module 310 is also configured to pause the target duration when the battery meets the second condition.

[0121] In some implementations, the second condition includes at least one of the following: The change in charge has reached the target value; The charging time has reached the target time.

[0122] In some implementations, the change in charge reaching a target value includes: The total charge change of the battery pack reaches the target value; or, The change in charge of each cell in the battery reaches the target value.

[0123] In some implementations, the adjustment module 320 is further configured to acquire the pause voltage difference corresponding to the entire battery pack and adjust the charging current of the entire battery pack according to the pause voltage difference.

[0124] In some embodiments, the adjustment module 320 is further configured to acquire the pause voltage difference corresponding to each of the cells in the battery, and adjust the charging current of the cells according to the pause voltage difference.

[0125] In some embodiments, the battery charging device 300 may further include: The trigger module pauses the target duration when the battery meets the trigger condition and the second condition.

[0126] In some implementations, the triggering condition includes at least one of the following: The first count is greater than the first target count, where the first count is the number of times the battery performs high-power charging, and the charging power of the high-power charging is greater than the target power; The second number of times is greater than the second target number of times, where the second number of times the battery is charged at a low temperature, and the temperature of the battery at the low temperature is less than the target temperature.

[0127] In some implementations, the target duration is determined based on the temperature of the battery, with a higher battery temperature corresponding to a shorter target duration.

[0128] This embodiment of the invention allows for a pause in battery charging for a target duration. After this pause, the charging current is adjusted. Timely adjustment of the charging current reduces the likelihood of lithium plating in the battery. Furthermore, because the charging current is adjusted after the target pause, battery charging efficiency is maintained to a certain extent. Figure 12 This is a block diagram illustrating a vehicle 800 according to an exemplary embodiment. For example... Figure 12 As shown, the vehicle 800 may include a processor 801 and a memory 802. The vehicle 800 may also include one or more of a multimedia component 803, an input / output (I / O) interface 804, and a communication component 805.

[0129] The processor 801 controls the overall operation of the vehicle 800 to complete all or part of the steps in the battery charging method described above. The memory 802 stores various types of data to support the operation of the vehicle 800. This data may include, for example, instructions for any application or method operating on the vehicle 800, and application-related data such as contact data, sent and received messages, pictures, audio, video, etc. The memory 802 can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as Static Random Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read-Only Memory (EPROM), Programmable Read-Only Memory (PROM), Read-Only Memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The multimedia component 803 may include a screen and audio components. The screen may be, for example, a touchscreen, and the audio component is used to output and / or input audio signals. For example, the audio component may include a microphone for receiving external audio signals. The received audio signals may be further stored in memory 802 or transmitted via communication component 805. The audio component also includes at least one speaker for outputting audio signals. I / O interface 804 provides an interface between processor 801 and other interface modules, such as a keyboard, mouse, buttons, etc. These buttons may be virtual or physical buttons. Communication component 805 is used for wired or wireless communication between the vehicle 800 and other devices. Wireless communication, such as Wi-Fi, Bluetooth, Near Field Communication (NFC), 2G, 3G, 4G, NB-IoT, eMTC, or other 5G technologies, or combinations thereof, is not limited here. Therefore, the corresponding communication component 805 may include: a Wi-Fi module, a Bluetooth module, an NFC module, etc.

[0130] In an exemplary embodiment, the vehicle 800 may be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components to perform the battery charging method described above.

[0131] In another exemplary embodiment, a computer-readable storage medium including program instructions is also provided, which, when executed by a processor, implement the steps of the battery charging method described above. For example, the computer-readable storage medium may be the memory 802 including program instructions described above, which may be executed by the processor 801 of the vehicle 800 to complete the battery charging method described above.

[0132] In another exemplary embodiment, a computer program product is also provided, the computer program product comprising a computer program executable by a programmable device, the computer program having a code portion for performing the battery charging method described above when executed by the programmable device.

[0133] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0134] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0135] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

[0136] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0137] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A battery charging method, characterized in that, The method includes: The target duration of pause when the battery is charging; After pausing for the target duration, the charging current of the battery is adjusted.

2. The battery charging method according to claim 1, characterized in that, The adjustment of the charging current of the battery includes: When the relationship between the pause voltage difference and the change in charge satisfies the first condition, the charging current of the battery is adjusted, wherein the pause voltage difference is the voltage difference of the battery before and after the charging pause.

3. The battery charging method according to claim 2, characterized in that, The first condition includes: The curve corresponding to the pause voltage difference and the change in charge shows an inflection point, and the pause voltage difference reaches its maximum value at this inflection point; or... The first derivative of the pause voltage difference with respect to the change in charge reaches zero.

4. The battery charging method according to any one of claims 1-3, characterized in that, The adjustment of the charging current of the battery includes: The charging current is reduced based on the voltage difference at the pause point.

5. The battery charging method according to claim 4, characterized in that, The step of reducing the charging current based on the pause voltage difference includes: Obtain the adjustment value corresponding to the pause voltage difference; The adjusted charging current is obtained by subtracting the adjustment value from the charging current.

6. The battery charging method according to claim 5, characterized in that, The step of obtaining the adjustment value corresponding to the pause voltage difference includes: The adjustment value corresponding to the pause voltage difference is obtained from the target mapping table, which stores the correspondence between the pause voltage difference and the adjustment value.

7. The battery charging method according to any one of claims 1-6, characterized in that, The target duration of the pause includes: When the battery meets the second condition, the target duration is paused.

8. The battery charging method according to claim 7, characterized in that, The second condition includes at least one of the following: The change in charge has reached the target value; The charging time has reached the target time.

9. The battery charging method according to claim 8, characterized in that, The change in charge reaching the target value includes: The total charge change of the battery pack reaches the target value; or, The change in charge of each cell in the battery reaches the target value.

10. The battery charging method according to claim 9, characterized in that, The adjustment of the charging current of the battery includes: Obtain the pause voltage difference corresponding to the entire battery pack, and adjust the overall charging current of the battery pack according to the pause voltage difference; or, Obtain the pause voltage difference corresponding to each cell in the battery, and adjust the charging current of the cell according to the pause voltage difference.

11. The battery charging method according to claim 7, characterized in that, The pause target duration when the battery meets the second condition includes: When the battery meets the trigger condition and the second condition, the target duration is paused.

12. The battery charging method according to claim 11, characterized in that, The triggering condition includes at least one of the following: The first count is greater than the first target count, where the first count is the number of times the battery performs high-power charging, and the charging power of the high-power charging is greater than the target power; The second number of times is greater than the second target number of times, where the second number of times the battery is charged at a low temperature, and the temperature of the battery at the low temperature is less than the target temperature.

13. The battery charging method according to any one of claims 1-12, characterized in that, The target duration is determined based on the temperature of the battery; the higher the battery temperature, the shorter the target duration.

14. A vehicle, characterized in that, The vehicles include: A memory on which computer programs are stored; A processor for executing the computer program in the memory to implement the steps of the method according to any one of claims 1-13.

15. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program performs the steps of the method described in any one of claims 1-13.

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