Charging method and related apparatus

Abstract

The application provides a charging method and related device. If the terminal voltage of a battery is less than a first voltage threshold, the battery is charged in a first charging mode through an adapter connected; the open circuit voltage of the battery at a first time is determined through state data of the battery; if the difference between the open circuit voltage at the first time and the open circuit voltage at a second time is less than a preset difference threshold, the open circuit voltage at the first time is less than the terminal voltage at the first time, and the open circuit voltage at the first time is greater than or equal to the first voltage threshold, the battery is charged in a second charging mode through the adapter, and the charging speed of the second charging mode is greater than the charging speed of the first charging mode. The battery with a lower shutdown voltage can be determined to meet the occasion of fast charging, and fast charging is performed when the battery meets the occasion of fast charging, thereby greatly improving the charging efficiency.

Description

Technical Field

[0001] This application relates to the field of charging technology, and in particular to a charging method and related apparatus. Background Technology

[0002] With the development of battery technology, the lithium-ion storage capacity of batteries is becoming stronger and stronger. The shutdown voltage of terminal devices equipped with these batteries is significantly lower than that of ordinary batteries, and their battery life is also stronger than that of ordinary batteries.

[0003] Conventional fast charging technologies typically increase the charging current rather than the charging voltage to achieve rapid battery charging. For example, a fast charging protocol might include three steps: identification, voltage regulation, and current regulation. Identification checks if the adapter supports the fast charging technology. Voltage regulation involves adjusting the adapter's bus output voltage to a specific range before fast charging begins. Current regulation involves gradually adjusting the adapter's bus voltage based on the terminal device's fast charging current request to achieve the target current output. However, current adjustable voltage settings are based on the shutdown voltage of ordinary batteries and cannot adapt to batteries with lower shutdown voltages. Summary of the Invention

[0004] In view of this, this application provides a charging method and related apparatus that can determine when a battery with a lower shutdown voltage is suitable for fast charging, and perform fast charging when the battery is suitable for fast charging, thereby greatly improving charging efficiency.

[0005] In a first aspect, embodiments of this application provide a charging method, the method comprising:

[0006] If the battery terminal voltage is less than the first voltage threshold, the battery is charged through the connected adapter in the first charging mode, and the magnitude of the charging current in the first charging mode changes periodically.

[0007] The open-circuit voltage of the battery at the first moment is determined by the battery's state data;

[0008] If the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is less than a preset difference threshold, and the open-circuit voltage at the first moment is less than the terminal voltage at the first moment, and the open-circuit voltage at the first moment is greater than or equal to the first voltage threshold, then the battery is charged through the adapter in a second charging mode, where the second moment is prior to the first moment in timing, and the charging speed of the second charging mode is greater than the charging speed of the first charging mode.

[0009] Secondly, embodiments of this application provide a charging device, the device comprising:

[0010] The first charging unit is used to charge the battery in a first charging mode through the connected adapter if the battery terminal voltage is less than a first voltage threshold. The magnitude of the charging current in the first charging mode changes periodically.

[0011] A parameter identification unit is used to determine the open-circuit voltage of the battery at a first moment based on the battery's state data;

[0012] The second charging unit is configured to charge the battery via the adapter in a second charging mode if the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is less than a preset difference threshold, and the open-circuit voltage at the first moment is less than the terminal voltage at the first moment, and the open-circuit voltage at the first moment is greater than or equal to the first voltage threshold. The second moment is prior to the first moment in the time sequence, and the charging speed of the second charging mode is greater than the charging speed of the first charging mode.

[0013] Thirdly, embodiments of this application provide a terminal device, including a processor, a memory, a communication interface, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the processor, and the programs include instructions for performing steps in any method of the first aspect of this application.

[0014] Fourthly, embodiments of this application provide a computer-readable storage medium storing a computer program for electronic data interchange, wherein the computer program causes a computer to perform some or all of the steps described in any method of the first aspect of this application.

[0015] Fifthly, embodiments of this application provide a computer program product, wherein the computer program product includes a non-transitory computer-readable storage medium storing a computer program, the computer program being operable to cause a computer to perform some or all of the steps described in any method of the first aspect of embodiments of this application.

[0016] As can be seen, using the above charging method and related devices, if the battery's terminal voltage is less than a first voltage threshold, the battery is charged through the connected adapter in a first charging mode, where the charging current changes periodically. The battery's open-circuit voltage at a first moment is determined using the battery's state data. If the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is less than a preset difference threshold, and the open-circuit voltage at the first moment is less than the terminal voltage at the first moment, and the open-circuit voltage at the first moment is greater than or equal to the first voltage threshold, the battery is charged through the adapter in a second charging mode, where the second moment is prior to the first moment in time sequence, and the charging speed of the second charging mode is greater than that of the first charging mode. Periodically changing current fluctuations can be used to accurately identify the open-circuit voltage, and fast charging can be performed when the open-circuit voltage meets the conditions. This allows for determining when a battery with a lower shutdown voltage is suitable for fast charging, and fast charging can be performed when the battery meets the fast charging conditions, greatly improving charging efficiency. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A system architecture diagram of a charging method provided in an embodiment of this application;

[0019] Figure 2 A schematic flowchart of a charging method provided in an embodiment of this application;

[0020] Figure 3 A schematic diagram of the equivalent circuit model of a battery provided in an embodiment of this application;

[0021] Figure 4 A schematic flowchart illustrating another charging method provided in an embodiment of this application;

[0022] Figure 5 This is a schematic diagram of the structure of a terminal device provided in an embodiment of this application;

[0023] Figure 6 This is a block diagram of the functional units of a charging device provided in an embodiment of this application. Detailed Implementation

[0024] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0025] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0026] It should be understood that the term "and / or" in this document is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this document indicates that the preceding and following related objects are in an "or" relationship. In the embodiments of this application, "multiple" refers to two or more.

[0027] In the embodiments of this application, "at least one item" or its similar expression refers to any combination of these items, including any combination of a single item or a plurality of items. "One or more" means one or more, while "multiple" means two or more. For example, "at least one item" of a, b, or c can represent the following seven cases: a, b, c; a and b; a and c; b and c; a, b, and c. Each of a, b, and c can be an element or a set containing one or more elements.

[0028] In this application, the term "connection" refers to various connection methods, such as direct connection or indirect connection, to achieve communication between devices. This application does not impose any limitations on this.

[0029] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0030] The following describes the relevant content, concepts, meanings, technical issues, technical solutions, and beneficial effects involved in the embodiments of this application.

[0031] Currently, batteries with higher energy density have been developed, such as those using silicon as the negative electrode material. The minimum shutdown voltage of a terminal device equipped with a silicon negative electrode battery is 2.7V, while the minimum shutdown voltage of a terminal device equipped with a graphite battery is 3.3V. Since the current fast charging protocol is based on the shutdown voltage of the graphite battery, when the silicon negative electrode battery is turned off in normal charging mode, the battery voltage is lower than a certain level. Because the voltage will continue to drop when the battery is consuming power, it will never be able to adjust the voltage to the voltage range set by the current fast charging protocol, thus remaining in the voltage adjustment step and unable to perform fast charging.

[0032] To address the aforementioned issues, embodiments of this application provide a charging method and related apparatus. This method utilizes periodically varying current fluctuations to accurately determine the open-circuit voltage and performs fast charging when the open-circuit voltage meets certain conditions. Specifically, it can identify the timing for fast charging for batteries with lower shutdown voltages and perform fast charging when the battery meets these conditions, thereby significantly improving charging efficiency.

[0033] Please see Figure 1 , Figure 1 The system architecture diagram of a charging method provided in this application embodiment includes an adapter 110, an interface circuit 120, an overvoltage protection module 130, a power management integrated circuit 140, a charge pump 150, a dedicated integrated circuit 160, and a battery 170. The interface circuit 120, the overvoltage protection module 130, the power management integrated circuit 140, the charge pump 150, the dedicated integrated circuit 160, and the battery 170 are all internal structures of the terminal device.

[0034] In this circuit, the adapter 110 is connected to the battery 170 in sequence through the interface circuit 120, the overvoltage protection module 130, and the power management integrated circuit 140. This charging path is a normal charging path. The adapter 110 is also connected to the battery 170 in sequence through the interface circuit 120 and the charge pump 150. This charging path is a fast charging path.

[0035] In this embodiment, the dedicated integrated circuit 160 is connected to the charge pump 150, which is also connected to the overvoltage protection module 130. The dedicated integrated circuit 160 can perform encrypted communication with the adapter 110 to identify whether the adapter 110 supports the fast charging protocol. The dedicated integrated circuit 160 can also control the overvoltage protection pin of the overvoltage protection module 130 to shut down the normal charging path. It can be understood that the first charging mode in this application embodiment is a charging mode that uses the normal charging path but controls the periodic change of the charging current. The second charging mode in this application embodiment is a charging mode that uses the fast charging path. It can be understood that the charging speed of the second charging mode is greater than that of the first charging mode. The concept of charging speed can be understood as the magnitude of the charging power. The greater the charging power, the faster the charging speed. For example, the charging voltage of the first charging mode is 5V, the charging current is 2A, and the charging power is 10W. The charging power of the second charging mode is 5V, the charging current is 6A, and the charging power is 30W.

[0036] Among them, adapter 110 is an adapter that supports fast charging protocol. When adapter 110 is connected to interface circuit 120, adapter 110 is first identified as a dedicated charging port (DCP) through BC1.2 protocol and charged through normal charging path. Then, when the battery terminal voltage is greater than or equal to the first voltage threshold, D+D- switch can be used to enable dedicated integrated circuit 160 and adapter 110 to conduct fast charging communication through D+D-. After the fast charging communication handshake is completed, the output of adapter 110 is directly charged to battery 170 through charge pump 150 after passing through interface circuit 120.

[0037] When the battery terminal voltage is less than the first voltage threshold, the battery 170 can be charged in the first charging mode through the adapter 110, and the parameters of the equivalent circuit model of the battery 170 can be identified to estimate the open circuit voltage at the current moment. The open circuit voltage at this time is used to determine whether the battery 170 meets the conditions for fast charging. If it does, the battery 170 is charged in the second charging mode through the adapter 110. If it does not meet the conditions, normal charging continues to increase the battery terminal voltage.

[0038] As can be seen, the above system architecture allows for the accurate determination of the open-circuit voltage by periodically varying current fluctuations for batteries with low shutdown voltages without increasing hardware costs. Fast charging can then be performed when the open-circuit voltage meets the requirements. In other words, it is possible to determine when batteries with even lower shutdown voltages are suitable for fast charging and to perform fast charging when the battery meets the requirements, thus greatly improving charging efficiency.

[0039] The following is combined Figure 2 One charging method according to an embodiment of this application will be described. Figure 2 This is a flowchart illustrating a charging method provided in an embodiment of this application. The method is executed by a terminal device, which includes a battery, and specifically includes the following steps:

[0040] Step 201: If the battery terminal voltage is less than the first voltage threshold, the battery is charged in the first charging mode through the connected adapter.

[0041] The first voltage threshold can be determined by the shutdown voltage previously supported by the fast charging protocol. For example, if the shutdown voltage previously supported by the fast charging protocol is 3.3V, then the first voltage threshold can be set to 3.3V. No specific limitation is made here. The charging current of the first charging mode changes periodically. It should be noted that when not charging, due to the power consumption of the system, the open circuit voltage of the battery at this time must be greater than the terminal voltage at this time.

[0042] In one possible embodiment, if the terminal voltage is less than the first voltage threshold, a first charging current, a second charging current, a first charging duration, and a second charging duration are determined, wherein the first charging current is greater than the second charging current. The battery is charged through the adapter using either the first charging current or the second charging current, where the duration of each use of the first charging current is the first charging duration, and the duration of each use of the second charging current is the second charging duration. Specifically, the first charging duration and the second charging duration can be the same or different. There is no limitation on whether the first charging current or the second charging current is used first. It can be understood that after charging the battery with the first charging current and maintaining the first charging duration, the system switches to charging the battery with the second charging current and maintaining the second charging duration, and so on, performing alternating charging.

[0043] The sum of the first charging current and the second charging current should be less than or equal to the normal charging current. For example, if the adapter's output current is 2A during normal charging, the first charging current can be set to 1200mA, the second charging current can be set to 800mA, the first charging duration can be set to 5 seconds, and the second charging duration can also be set to 5 seconds. First, set the 800mA charging current to the charging IC register and record the initial setting time start_time = current time. Continuously acquire the system time current_time and check if 5 seconds have passed since the previous start_time. If not, continue charging with 800mA. If 5 seconds have passed, set 1200mA as the charging current to the charging IC register and record the initial setting time start_time = current time. Similarly, continuously acquire the system time current_time and check if 5 seconds have passed since the previous start_time. If not, continue charging with 1200mA. If 5 seconds have passed, return to the previous 800mA charging.

[0044] It is evident that since the parameter identification algorithm requires a change in charging current to converge, the algorithm cannot converge if only a constant current from normal charging is used. Therefore, creating a periodically changing current through the first charging mode can provide a foundation for subsequent parameter identification.

[0045] In one possible embodiment, if the battery terminal voltage is less than a first voltage threshold, before charging the battery in the first charging mode through the connected adapter, the current terminal voltage can be obtained and the adapter identified. If the adapter supports the second charging mode, the battery can be charged in the fourth charging mode through the adapter. The charging current of the fourth charging mode remains unchanged. It should be noted that the fourth charging mode is the normal charging mode, and the first charging mode is a charging mode obtained by setting a periodic change in the current based on the fourth charging mode.

[0046] Specifically, the adapter type is identified using the BC1.2 protocol. If it is identified as a non-DCP (e.g., SDP or CDP for computers), the normal charging path for non-DCP is used. If it is a DCP, the normal charging path for DCP is used, and D+D- is switched to the dedicated integrated circuit. Then, the dedicated integrated circuit communicates with the adapter using D+D-. During the communication process, the frame header of the communication frame is used to identify whether the adapter supports the fast charging protocol in this embodiment. If the adapter supports the fast charging protocol in this embodiment, the battery is charged in normal charging mode through the adapter, and the terminal voltage is checked to see if it is less than the first voltage threshold.

[0047] Therefore, it can be determined whether the adapter supports the fast charging protocol in the embodiments of this application, which serves as a prerequisite for executing the charging method in the embodiments of this application.

[0048] Step 202: Determine the open-circuit voltage of the battery at the first moment using the battery's state data. The state data may include terminal voltage, current, and other data from multiple moments. The first moment can be understood as the current moment, and the second moment as the moment before the first moment. An equivalent circuit model of the battery can be constructed first, with its initial open-circuit voltage equal to the terminal voltage at the same moment. Then, the state-space equation of the equivalent circuit model is updated based on the terminal voltage at the second moment, the battery current at the second moment, the battery current at the first moment, and the terminal voltage at the first moment. Finally, the measurement error and Kalman gain are determined using a recursive least squares method with a forgetting factor, and the covariance matrix and model parameters of the battery are updated to determine the open-circuit voltage at the first moment.

[0049] To facilitate understanding, let's first combine... Figure 3 The equivalent circuit model of the battery in the embodiments of this application is described below. See [link to relevant documentation]. Figure 3 , Figure 3 This application provides a schematic diagram of the equivalent circuit model of a battery, including a power supply and an Ohmic resistor R. o diffusion resistance R p and diffusion capacitance C p Open circuit voltage with U OCV This indicates that the battery's terminal voltage is expressed in U. t This indicates that the ohmic resistance R o R represents the resistance of the battery module as charge accumulates and dissipates in the double layer. This first-order equivalent circuit model can be used to simulate diffusion voltage. This slow voltage change trend is due to polarization caused by the imbalance of electrode ion concentrations resulting from the slow diffusion of lithium ions in the battery. p and C p These are respectively called diffusion resistance and diffusion capacitance. According to circuit principles, the electrical behavior of the first-order equivalent circuit model can be written in discrete-time form:

[0050]

[0051] Where T is the time interval between two consecutive samples, for example, if the sampling interval is 10s, then T is equal to 10s. K and k are the nth times, for example, the kth time + 1 is the k+1th time. e is the base of the natural logarithm, which is approximately equal to 2.71828.

[0052] Dynamic voltage can be defined as:

[0053] Ue (k)=U t (k)-U ocv (k)=U P (K)+R O I(k)

[0054] After sorting, we can obtain:

[0055]

[0056] Substituting the dynamic voltage expression into the terminal voltage expression, we get:

[0057]

[0058] Next, we can define the model identification vector: in

[0059]

[0060] We can obtain:

[0061] θ k (3)=(1-θ k (4))U ocv =U ocv -θ k (4)U ocv

[0062] U ocv =θ k (4)U ocv +θ k (3)

[0063] U ocv =θ k (4)U ocv (k-1)+θ k (3)

[0064] Among them, the third element θ k (3) is (1-α)U ocv The 4th element θ k (4) is α.

[0065] Therefore, as long as the parameters are identified and θ is estimated in real time... k (3) and θ k (4) can iteratively estimate the open-circuit voltage U at the current moment using the open-circuit voltage at the previous moment. ocv(k) To enhance the response and adaptability of open-circuit voltage parameter identification to dynamic operating conditions, a recursive least squares formula with a forgetting factor is introduced:

[0066] Initialize P0, λ,

[0067]

[0068] Recursive least squares (RLS) is a recursive algorithm used to solve linear regression problems. Its goal is to estimate system parameters by minimizing the sum of squared errors. RLS with a forgetting factor introduces a forgetting factor into the standard RLS algorithm, giving new data greater weight than old data, thus accelerating the response to parameter changes. The forgetting factor λ is typically between 0.95 and 0.995, with λ = 1 indicating no data has been forgotten. At low sampling frequencies, a smaller λ value (0.95) is generally better because it allows for faster forgetting of old data and quicker adaptation to new data, thus better tracking of the system's dynamic changes.

[0069] After explaining the equivalent circuit model above, the parameter identification algorithm in the embodiments of this application will be described in detail below. Before running, relevant parameters need to be initialized. For example, the initial battery impedance is set to 0, and the initial open-circuit voltage OCV is set to the current battery terminal voltage. The closer the value is to the actual value, the faster the algorithm converges. The initial covariance matrix is ​​set as large as possible, such as 10 to the power of 6, so that the initial iteration results are more reliable to the measured values. This parameter identification algorithm can be executed periodically, such as once every 2 seconds. It can be understood that each execution outputs an estimated open-circuit voltage. Since the above formula has shown the specific calculation process, the detailed formula derivation is not shown here, only the main algorithm flow is shown:

[0070] S1, obtain the battery terminal voltage U at the current time k. t (k) and battery current I t (k).

[0071] S2, using φ k =[I(k-1),I(k),1,U t (k-1)] T Update the state variables of the state-space equation.

[0072] S3, use To calculate the measurement error.

[0073] S4, used To calculate the Kalman gain.

[0074] S5, using To update the covariance matrix.

[0075] S6, using To update the parameters of the equivalent circuit model.

[0076] S7, using OCV(k) = θ k(4)*OCV(k-1)+θ k (3) To calculate the estimated OCV.

[0077] It can be understood that OCV(k) is the open-circuit voltage at the current moment, and OCV(k-1) is the open-circuit voltage at the previous moment. In this step, OCV(k) is the open-circuit voltage at the first moment, and OCV(k-1) is the open-circuit voltage at the second moment. The second moment can be the initial moment.

[0078] As can be seen, since the battery forms a loop during the charging process, the open-circuit voltage of the battery cannot be directly measured. It is necessary to estimate the open-circuit voltage of the battery to obtain an accurate open-circuit voltage, which can provide reliable data support for subsequent judgment on whether fast charging can be performed.

[0079] Step 203: If the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is less than a preset difference threshold, and the open-circuit voltage at the first moment is less than the terminal voltage at the first moment, and the open-circuit voltage at the first moment is greater than or equal to the first voltage threshold, then the battery is charged through the adapter in the second charging mode.

[0080] In this context, the second moment precedes the first moment in the time sequence. The charging speed of the second charging mode is greater than that of the first charging mode. This can be understood as a fast charging mode, where the charging speed is higher than that of the first charging mode. Charging speed can be understood as the magnitude of charging power; the higher the charging power, the faster the charging speed. For example, the first charging mode has a charging voltage of 5V, a charging current of 2A, and a charging power of 10W. The second charging mode has a charging power of 5V and a charging current of 6A, i.e., a charging power of 30W. However, current fast charging protocols require the battery's terminal voltage to be higher than a first voltage threshold before voltage adjustment can be initiated to activate fast charging. Directly measuring the terminal voltage during the charging process cannot accurately determine whether fast charging is possible. The timing is crucial. By estimating the open-circuit voltage, and considering that the open-circuit voltage at this moment is less than the terminal voltage (the opposite of the non-charging situation), combined with the extremely short running cycle of the parameter identification algorithm, the change in open-circuit voltage within a short period should be minimal. Therefore, using "if the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is less than a preset difference threshold, and the open-circuit voltage at the first moment is less than the terminal voltage at the first moment" as the convergence criterion for the parameter identification algorithm is very reasonable. In other words, the calculated open-circuit voltage at this moment can be considered valid and correct. Then, it is determined whether the open-circuit voltage at this moment is greater than 3.3V. If the open-circuit voltage at this moment is greater than 3.3V, it means that continuous charging has made the battery voltage high enough. At this time, the first charging mode can be turned off, and the second charging mode can be directly entered for fast charging.

[0081] As can be seen, this allows for fast charging when the open-circuit voltage meets the requirements. Specifically, it allows for determining when a battery with a lower shutdown voltage is eligible for fast charging and then performing fast charging when that battery is eligible, thus greatly improving charging efficiency.

[0082] In one possible embodiment, if the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is greater than or equal to the preset difference threshold, or the open-circuit voltage at the first moment is greater than or equal to the terminal voltage at the first moment, or the open-circuit voltage at the first moment is less than the first voltage threshold, then the battery is charged through the adapter in the first charging mode; parameter identification is performed on the equivalent circuit model to determine the open-circuit voltage of the battery at the third moment; if the difference between the open-circuit voltage at the third moment and the open-circuit voltage at the first moment is less than the preset difference threshold, and the open-circuit voltage at the third moment is less than the terminal voltage at the third moment, and the open-circuit voltage at the third moment is greater than the first voltage threshold, then the battery is charged through the adapter in the second charging mode, wherein the first moment is prior to the third moment in timing.

[0083] It is understandable that the above parameter identification algorithm can be re-executed at this time. OCV(k) is the open-circuit voltage at the third time, OCV(k-1) is the open-circuit voltage at the first time, and so on. If the parameter identification algorithm does not converge, it can be repeatedly executed until the parameter identification algorithm converges and the open-circuit voltage at the current time is greater than or equal to the first voltage threshold. The condition for the algorithm to converge is that the difference between the open-circuit voltage at the current time and the open-circuit voltage at the previous time is less than the preset difference threshold, and the open-circuit voltage at the current time is less than the terminal voltage at the current time.

[0084] As can be seen, this method can accurately determine when the battery meets the conditions for fast charging, and fast charging can be performed when the battery meets the conditions for fast charging, which greatly improves charging efficiency.

[0085] The following is combined Figure 4 Another charging method provided in the embodiments of this application will be described. Figure 4 A flowchart illustrating another charging method provided in this application embodiment specifically includes the following steps:

[0086] Step 401: If the battery terminal voltage is less than the first voltage threshold, the battery is charged in the first charging mode through the connected adapter.

[0087] Step 402: Determine the open-circuit voltage of the battery at the first moment using the battery's state data.

[0088] Step 403: If the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is greater than or equal to the preset difference threshold, or the open-circuit voltage at the first moment is greater than or equal to the terminal voltage at the first moment, or the open-circuit voltage at the first moment is less than the first voltage threshold, then obtain the battery temperature at the first moment and the number of charge-discharge cycles at the first moment.

[0089] Among them, the parameter identification algorithm has a low probability of not converging. This is generally affected by factors such as battery voltage, battery current sampling error, and synchronization between battery voltage and battery current. Therefore, when it does not converge, the battery temperature and the number of charge-discharge cycles at this time can be obtained to provide data support for subsequent judgment.

[0090] In one possible embodiment, step 403 can be executed when the parameter identification algorithm fails to converge for the first time, or step 403 can be executed when the number of times the parameter identification algorithm fails to converge reaches a preset threshold. No specific limitation is made here.

[0091] Step 404: Determine the target terminal voltage threshold based on the battery temperature at the first moment and the number of charge-discharge cycles at the first moment.

[0092] The target voltage threshold can be configured through prior experiments, such as setting the battery temperature T to 0-5 degrees, 5-12 degrees, 12-20 degrees, 20-43 degrees, or 43-55 degrees, and the battery cycle count to 0-200, 200-400, 400-800, 800-1000, or more than 1000 cycles.

[0093] The target terminal voltage was measured at different temperatures and with different cycle numbers, as shown in the table below:

[0094]

[0095] The target terminal voltage is shown here. It can be seen that the target terminal voltage threshold can be determined based on the battery temperature at the first moment and the number of charge-discharge cycles at the first moment. For example, if the battery temperature at the first moment is 5-12 degrees and the number of cycles at the first moment is 200-400, then the target terminal voltage threshold is 3.45V.

[0096] As can be seen, this provides data support for determining whether a second charging mode can be executed based on the terminal voltage.

[0097] Step 405: If the terminal voltage at the first moment is greater than or equal to the target terminal voltage threshold, then the battery is charged through the adapter in the second charging mode.

[0098] If the terminal voltage at the first moment is greater than or equal to the target terminal voltage threshold, then the battery has been continuously charged to the limit voltage of the current temperature and the current number of cycles, making the battery voltage high enough. At this point, the first charging mode can be stopped and the second charging mode can be started.

[0099] As can be seen, this can prevent continuous parameter identification when the parameter identification algorithm fails to converge. By obtaining the current battery temperature and the current number of charging cycles, it can determine whether the current terminal voltage has reached the target terminal voltage threshold. Fast charging can be performed when the battery meets the time for fast charging, which greatly improves charging efficiency.

[0100] In one possible embodiment, if the terminal voltage at the first moment is less than the target terminal voltage threshold, the battery is charged via the adapter in a third charging mode until the terminal voltage is greater than or equal to the target terminal voltage threshold. The charging speed of the third charging mode is less than that of the second charging mode. The third charging mode can be either the first or the fourth charging mode; it is understood that the third charging mode is a normal charging mode and will not be elaborated upon here.

[0101] As can be seen, using the above charging method, if the battery's terminal voltage is less than a first voltage threshold, the battery is charged through the connected adapter in a first charging mode, where the charging current changes periodically. The battery's open-circuit voltage at a first moment is determined using the battery's state data. If the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is less than a preset difference threshold, and the open-circuit voltage at the first moment is less than the terminal voltage at the first moment, and the open-circuit voltage at the first moment is greater than or equal to the first voltage threshold, the battery is charged through the adapter in a second charging mode, where the second moment is prior to the first moment in time sequence, and the charging speed of the second charging mode is greater than that of the first charging mode. Periodically changing current fluctuations can be used to accurately identify the open-circuit voltage, and fast charging can be performed when the open-circuit voltage meets the conditions. This allows for determining when a battery with a lower shutdown voltage is suitable for fast charging, and fast charging can be performed when the battery meets the fast charging conditions, significantly improving charging efficiency.

[0102] For details not explained in the above steps, please refer to [link / reference]. Figure 2 The details of the intermediate steps will not be elaborated here.

[0103] The following is combined Figure 5 An embodiment of the present application will be described. Figure 5 This is a schematic diagram of the structure of a terminal device according to an embodiment of this application. The terminal device 500 includes a processor 501, a memory 502, and a communication bus 503 for connecting the processor 501 and the memory 502.

[0104] In some possible implementations, memory 502 includes, but is not limited to, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), or compact disc read-only memory (CD-ROM), which is used to store program code executed by terminal device 500 and data transmitted.

[0105] In some possible implementations, the terminal device 500 also includes a communication interface for receiving and sending data.

[0106] In some possible implementations, processor 501 may be one or more central processing units (CPUs). If processor 501 is a central processing unit (CPU), the central processing unit (CPU) may be a single-core central processing unit (CPU) or a multi-core central processing unit (CPU).

[0107] In some possible implementations, processor 501 may be a baseband chip, a chip, a central processing unit (CPU), a general-purpose processor, a DSP, an ASIC, an FPGA, or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof.

[0108] In specific implementation, the processor 501 in the terminal device 500 executes the program instructions 521 stored in the memory 502 to perform the following operations:

[0109] If the battery terminal voltage is less than the first voltage threshold, the battery is charged through the connected adapter in the first charging mode, and the magnitude of the charging current in the first charging mode changes periodically.

[0110] The open-circuit voltage of the battery at the first moment is determined by the battery's state data;

[0111] If the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is less than a preset difference threshold, and the open-circuit voltage at the first moment is less than the terminal voltage at the first moment, and the open-circuit voltage at the first moment is greater than or equal to the first voltage threshold, then the battery is charged through the adapter in a second charging mode, where the second moment is prior to the first moment in timing, and the charging speed of the second charging mode is greater than the charging speed of the first charging mode.

[0112] As can be seen, using the above charging method and related devices, if the battery's terminal voltage is less than a first voltage threshold, the battery is charged through the connected adapter in a first charging mode, where the charging current changes periodically. The battery's open-circuit voltage at a first moment is determined using the battery's state data. If the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is less than a preset difference threshold, and the open-circuit voltage at the first moment is less than the terminal voltage at the first moment, and the open-circuit voltage at the first moment is greater than or equal to the first voltage threshold, the battery is charged through the adapter in a second charging mode, where the second moment is prior to the first moment in time sequence, and the charging speed of the second charging mode is greater than that of the first charging mode. Periodically changing current fluctuations can be used to accurately identify the open-circuit voltage, and fast charging can be performed when the open-circuit voltage meets the conditions. This allows for determining when a battery with a lower shutdown voltage is suitable for fast charging, and fast charging can be performed when the battery meets the fast charging conditions, greatly improving charging efficiency.

[0113] The above primarily describes the solutions of the embodiments of this application from the perspective of the method execution process. It is understood that, in order to achieve the above functions, the terminal device includes the corresponding hardware structure and / or software modules for executing each function. Those skilled in the art should readily recognize that, based on the units and algorithm steps of the various examples described in the embodiments provided herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0114] This application embodiment can divide the terminal device into functional units according to the above method example. For example, each function can be divided into a separate functional unit, or two or more functions can be integrated into one processing unit. The integrated unit can be implemented in hardware or as a software functional unit. It should be noted that the unit division in this application embodiment is illustrative and only represents one logical functional division. In actual implementation, there may be other division methods.

[0115] When dividing each function into modules according to its corresponding function. Figure 6 This application provides a functional unit block diagram of a charging device 600, which includes:

[0116] The first charging unit 610 is used to charge the battery in a first charging mode through the connected adapter if the battery terminal voltage is less than a first voltage threshold. The magnitude of the charging current in the first charging mode changes periodically.

[0117] The parameter identification unit 620 is used to determine the open-circuit voltage of the battery at a first moment based on the battery's state data.

[0118] The second charging unit 630 is configured to charge the battery via the adapter in a second charging mode if the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is less than a preset difference threshold, and the open-circuit voltage at the first moment is less than the terminal voltage at the first moment, and the open-circuit voltage at the first moment is greater than or equal to the first voltage threshold. The second moment is prior to the first moment in the time sequence, and the charging speed of the second charging mode is greater than the charging speed of the first charging mode.

[0119] In one possible embodiment, regarding charging the battery in a first charging mode via an adapter when the battery's terminal voltage is less than a first voltage threshold, the first charging unit 610 is specifically used for:

[0120] If the terminal voltage is less than the first voltage threshold, then the first charging current, the second charging current, the first charging duration and the second charging duration are determined, wherein the first charging current is greater than the second charging current.

[0121] The battery is charged by the adapter with either the first charging current or the second charging current, wherein the duration of each charging current is the first charging duration and the duration of each charging current is the second charging duration.

[0122] In one possible embodiment, the parameter identification unit 620 is specifically used to: determine the open-circuit voltage of the battery at a first moment using the battery's state data.

[0123] Construct an equivalent circuit model of the battery, wherein the initial open-circuit voltage of the equivalent circuit model is equal to the terminal voltage at the same moment;

[0124] The state-space equations of the equivalent circuit model are updated based on the terminal voltage at the second time, the battery current at the second time, the battery current at the first time, and the terminal voltage at the first time.

[0125] The measurement error and Kalman gain are determined by recursive least squares with a forgetting factor, and the covariance matrix and model parameters of the battery are updated to determine the open-circuit voltage at the first moment.

[0126] In one possible embodiment, after determining the open-circuit voltage of the battery at a first moment using the battery's state data, the first charging unit 610 is further configured to:

[0127] If the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is greater than or equal to the preset difference threshold, or the open-circuit voltage at the first moment is greater than or equal to the terminal voltage at the first moment, or the open-circuit voltage at the first moment is less than the first voltage threshold, then the battery is charged through the adapter in the first charging mode.

[0128] The parameter identification unit 620 is also used to perform parameter identification on the equivalent circuit model to determine the open-circuit voltage of the battery at the third time.

[0129] The second charging unit is further configured to charge the battery via the adapter in the second charging mode if the difference between the open-circuit voltage at the third time and the open-circuit voltage at the first time is less than the preset difference threshold, and the open-circuit voltage at the third time is less than the terminal voltage at the third time, and the open-circuit voltage at the third time is greater than the first voltage threshold. The first time is located before the third time in the timing sequence.

[0130] In one possible embodiment, after determining the open-circuit voltage of the battery at a first moment using the battery's state data, the charging device 600 further includes an acquisition unit configured to acquire the battery temperature at the first moment and the number of charge-discharge cycles at the first moment if the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is greater than or equal to the preset difference threshold, or the open-circuit voltage at the first moment is greater than or equal to the terminal voltage at the first moment, or the open-circuit voltage at the first moment is less than the first voltage threshold; and determine a target terminal voltage threshold based on the battery temperature at the first moment and the number of charge-discharge cycles at the first moment.

[0131] The second charging unit 630 is further configured to charge the battery in a second charging mode via the adapter if the terminal voltage at the first moment is greater than or equal to the target terminal voltage threshold.

[0132] In one possible embodiment, after determining the target terminal voltage threshold based on the battery temperature at the first moment and the number of charge-discharge cycles at the first moment, the acquisition unit is further configured to charge the battery in a third charging mode via the adapter if the terminal voltage at the first moment is less than the target terminal voltage threshold, until the terminal voltage is greater than or equal to the target terminal voltage threshold, wherein the charging speed of the third charging mode is less than the charging speed of the second charging mode.

[0133] In one possible embodiment, before charging the battery in a first charging mode via the connected adapter when the battery's terminal voltage is less than a first voltage threshold, the first charging unit 610 is further configured to:

[0134] Obtain the terminal voltage;

[0135] The adapter is identified. If the adapter supports the second charging mode, the battery is charged through the adapter in a fourth charging mode, wherein the charging current of the fourth charging mode remains unchanged.

[0136] As can be seen, using the above charging method and related devices, if the battery's terminal voltage is less than a first voltage threshold, the battery is charged through the connected adapter in a first charging mode, where the charging current changes periodically. The battery's open-circuit voltage at a first moment is determined using the battery's state data. If the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is less than a preset difference threshold, and the open-circuit voltage at the first moment is less than the terminal voltage at the first moment, and the open-circuit voltage at the first moment is greater than or equal to the first voltage threshold, the battery is charged through the adapter in a second charging mode, where the second moment is prior to the first moment in time sequence, and the charging speed of the second charging mode is greater than that of the first charging mode. Periodically changing current fluctuations can be used to accurately identify the open-circuit voltage, and fast charging can be performed when the open-circuit voltage meets the conditions. This allows for determining when a battery with a lower shutdown voltage is suitable for fast charging, and fast charging can be performed when the battery meets the fast charging conditions, greatly improving charging efficiency.

[0137] It should be noted that the specific implementation of each operation can be described in the corresponding description of the method embodiments shown above. The charging device 600 can be used to execute the method embodiments of this application, and will not be described again here.

[0138] This application also provides a chip, including a processor, a memory, and a computer program or instructions stored in the memory, wherein the processor executes the computer program or instructions to implement the steps described in the above method embodiments.

[0139] This application also provides a chip module, including a transceiver component and a chip. The chip includes a processor, a memory, and a computer program or instructions stored in the memory, wherein the processor executes the computer program or instructions to implement the steps described in the above method embodiments.

[0140] This application also provides a computer storage medium storing a computer program for electronic data interchange, which causes a computer to perform some or all of the steps of any of the methods described in the above method embodiments, wherein the computer includes a terminal device.

[0141] This application also provides a computer program product, which includes a non-transitory computer-readable storage medium storing a computer program operable to cause a computer to perform some or all of the steps of any of the methods described in the above method embodiments. The computer program product may be a software installation package, and the computer may include a terminal device.

[0142] It should be noted that, for the sake of simplicity, the above embodiments are all described as a series of actions. Those skilled in the art should understand that this application is not limited to the described order of actions, as some steps in the embodiments of this application can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions, steps, modules, or units involved are not necessarily essential to the embodiments of this application.

[0143] In the above embodiments, the descriptions of each embodiment in this application have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0144] The steps of the methods or algorithms described in the embodiments of this application can be implemented in hardware or by a processor executing software instructions. The software instructions can consist of corresponding software modules, which can be stored in RAM, flash memory, ROM, EPROM, electrically erasable programmable read-only memory (EEPROM), registers, hard disk, portable hard disk, read-only optical disk (CD-ROM), or any other form of storage medium well known in the art. An exemplary storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and storage medium can reside in an ASIC. Furthermore, the ASIC can reside in a terminal device or management device. Alternatively, the processor and storage medium can exist as discrete components in the terminal device or management device.

[0145] Those skilled in the art will recognize that, in one or more of the examples above, the functions described in the embodiments of this application can be implemented, in whole or in part, by software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, in the form of a computer program product. This computer program product includes one or more computer instructions. When these computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium accessible to a computer or a data storage device such as a server or data center that integrates one or more available media. The available media can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., digital video discs (DVDs)), or semiconductor media (e.g., solid-state disks (SSDs)).

[0146] The modules / units included in the various devices and products described in the above embodiments can be software modules / units, hardware modules / units, or a combination of both. For example, for devices and products applied to or integrated into a chip, all modules / units can be implemented using hardware methods such as circuits, or at least some modules / units can be implemented using software programs that run on a processor integrated within the chip, while the remaining (if any) modules / units can be implemented using hardware methods such as circuits. For devices and products applied to or integrated into a chip module, all modules / units can be implemented using hardware methods such as circuits. Different modules / units can be located in the same component (e.g., chip, circuit module, etc.) or different components of the chip module, or at least some modules / units can be implemented using hardware methods such as circuits. The implementation is achieved through a software program that runs on a processor integrated within the chip module. The remaining modules / units (if any) can be implemented using hardware methods such as circuits. For various devices and products applied to or integrated into terminal equipment, each of their modules / units can be implemented using hardware methods such as circuits. Different modules / units can be located in the same component (e.g., chip, circuit module, etc.) or different components within the terminal equipment. Alternatively, at least some modules / units can be implemented using a software program that runs on a processor integrated within the terminal equipment, while the remaining modules / units (if any) can be implemented using hardware methods such as circuits.

[0147] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the embodiments of this application. It should be understood that the above descriptions are merely specific embodiments of the embodiments of this application and are not intended to limit the protection scope of the embodiments of this application. Any modifications, equivalent substitutions, improvements, etc., made on the basis of the technical solutions of the embodiments of this application should be included within the protection scope of the embodiments of this application.

Claims

1. A charging method, characterized in that, The method includes: If the battery terminal voltage is less than the first voltage threshold, the battery is charged through the connected adapter in the first charging mode, and the magnitude of the charging current in the first charging mode changes periodically. The open-circuit voltage of the battery at the first moment is determined by the battery's state data; If the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is less than a preset difference threshold, and the open-circuit voltage at the first moment is less than the terminal voltage at the first moment, and the open-circuit voltage at the first moment is greater than or equal to the first voltage threshold, then the battery is charged through the adapter in a second charging mode, where the second moment is prior to the first moment in timing, and the charging speed of the second charging mode is greater than the charging speed of the first charging mode.

2. The method according to claim 1, characterized in that, If the battery's terminal voltage is less than a first voltage threshold, the battery is charged via the connected adapter in a first charging mode, including: If the terminal voltage is less than the first voltage threshold, then the first charging current, the second charging current, the first charging duration and the second charging duration are determined, wherein the first charging current is greater than the second charging current. The battery is charged by the adapter with either the first charging current or the second charging current, wherein the duration of each charging current is the first charging duration and the duration of each charging current is the second charging duration.

3. The method according to claim 1, characterized in that, Determining the open-circuit voltage of the battery at a first moment using the battery's state data includes: Construct an equivalent circuit model of the battery, wherein the initial open-circuit voltage of the equivalent circuit model is equal to the terminal voltage at the same moment; The state-space equations of the equivalent circuit model are updated based on the terminal voltage at the second time, the battery current at the second time, the battery current at the first time, and the terminal voltage at the first time. The measurement error and Kalman gain are determined by recursive least squares with a forgetting factor, and the covariance matrix and model parameters of the battery are updated to determine the open-circuit voltage at the first moment.

4. The method according to claim 1, characterized in that, After determining the open-circuit voltage of the battery at a first moment using the battery's state data, the method further includes: If the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is greater than or equal to the preset difference threshold, or the open-circuit voltage at the first moment is greater than or equal to the terminal voltage at the first moment, or the open-circuit voltage at the first moment is less than the first voltage threshold, then the battery is charged through the adapter in the first charging mode. The equivalent circuit model is subjected to parameter identification to determine the open-circuit voltage of the battery at the third time point; If the difference between the open-circuit voltage at the third moment and the open-circuit voltage at the first moment is less than the preset difference threshold, and the open-circuit voltage at the third moment is less than the terminal voltage at the third moment, and the open-circuit voltage at the third moment is greater than the first voltage threshold, then the battery is charged through the adapter in the second charging mode, wherein the first moment is prior to the third moment in timing.

5. The method according to claim 1, characterized in that, After determining the open-circuit voltage of the battery at a first moment using the battery's state data, the method further includes: If the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is greater than or equal to the preset difference threshold, or the open-circuit voltage at the first moment is greater than or equal to the terminal voltage at the first moment, or the open-circuit voltage at the first moment is less than the first voltage threshold, then the battery temperature at the first moment and the number of charge-discharge cycles at the first moment are obtained. The target terminal voltage threshold is determined based on the battery temperature at the first moment and the number of charge-discharge cycles at the first moment. If the terminal voltage at the first moment is greater than or equal to the target terminal voltage threshold, the battery is charged through the adapter in the second charging mode.

6. The method according to claim 5, characterized in that, After determining the target terminal voltage threshold based on the battery temperature at the first moment and the number of charge-discharge cycles at the first moment, the method further includes: If the terminal voltage at the first moment is less than the target terminal voltage threshold, the battery is charged through the adapter in a third charging mode until the terminal voltage is greater than or equal to the target terminal voltage threshold. The charging speed of the third charging mode is less than the charging speed of the second charging mode.

7. The method according to claim 1, characterized in that, If the battery's terminal voltage is less than a first voltage threshold, before charging the battery in a first charging mode via the connected adapter, the method further includes: Obtain the terminal voltage; The adapter is identified. If the adapter supports the second charging mode, the battery is charged through the adapter in a fourth charging mode, wherein the charging current of the fourth charging mode remains unchanged.

8. A charging device, characterized in that, The device includes: The first charging unit is used to charge the battery in a first charging mode through the connected adapter if the battery terminal voltage is less than a first voltage threshold. The magnitude of the charging current in the first charging mode changes periodically. A parameter identification unit is used to determine the open-circuit voltage of the battery at a first moment based on the battery's state data; The second charging unit is configured to charge the battery via the adapter in a second charging mode if the difference between the open-circuit voltage at the first moment and the open-circuit voltage at the second moment is less than a preset difference threshold, and the open-circuit voltage at the first moment is less than the terminal voltage at the first moment, and the open-circuit voltage at the first moment is greater than or equal to the first voltage threshold. The second moment is prior to the first moment in the time sequence, and the charging speed of the second charging mode is greater than the charging speed of the first charging mode.

9. A terminal device, characterized in that, include: Processor, memory, and one or more programs; The one or more programs are stored in the memory and configured to be executed by the processor, the programs including instructions for performing the steps of the method as described in any one of claims 1-7.

10. A computer storage medium, characterized in that, The computer storage medium stores a computer program, the computer program including program instructions, which, when executed by a processor, cause the processor to perform the method as described in any one of claims 1-7.

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