Battery lithium precipitation detection method and device and lithium battery

Abstract

The embodiment of the invention provides a battery lithium precipitation detection method and device and a lithium battery, and the method comprises the steps: obtaining the target resistance change rate of a strain sensor covering the surface of the lithium battery in the charging process of the lithium battery; and determining a lithium precipitation detection result of the lithium battery according to the target resistance change rate. The strain sensor is adhered to the surface of the lithium battery, so that the surface of the lithium battery is deformed when lithium is separated out, a conductive path in the strain sensor is driven to change, and the corresponding resistance is influenced, and therefore, on the basis of the target resistance change rate, in the charging process of the battery, the resistance of the lithium battery can be effectively changed. And the lithium precipitation detection result of the lithium battery is obtained on line.

Description

Technical Field

[0001] The present application relates to the field of terminal technology, and in particular to a battery lithium deposition detection method, device and lithium battery. Background Art

[0002] Lithium batteries are widely used in various electronic devices due to their advantages such as low pollution, high energy density, long cycle life and low self-discharge rate. Therefore, the issue of lithium battery safety has received widespread attention.

[0003] Among them, lithium plating is an abnormal phenomenon that may occur in the charging process of lithium batteries. Therefore, in order to ensure the safe use of lithium batteries, it is necessary to perform lithium plating detection on lithium batteries. At present, in the relevant technology, when performing lithium plating detection on lithium batteries, it is usually necessary to disassemble the lithium batteries when they are fully charged, and judge whether lithium plating occurs in the lithium batteries by observing the state of the lithium battery electrodes.

[0004] However, this implementation method requires the lithium battery to be separated from the electronic device and disassembled before it can be determined whether lithium deposition has occurred in the lithium battery, which makes it impossible to perform real-time lithium deposition detection on the lithium battery. Summary of the invention

[0005] The embodiments of the present application provide a battery lithium deposition detection method, device and lithium battery, which are applied in the field of terminal technology.

[0006] In a first aspect, an embodiment of the present application provides a method for detecting lithium deposition in a battery. The method comprises:

[0007] During the charging process of the lithium battery, a target resistance change rate of the strain sensor covered on the surface of the lithium battery is obtained, and then the lithium plating detection result of the lithium battery is determined according to the target resistance change rate.

[0008] In this implementation, by sticking a strain sensor on the surface of the lithium battery, when lithium deposition occurs in the lithium battery, the surface will be deformed, which will cause the conductive path in the strain sensor to change, and the corresponding resistance will be affected. Therefore, based on the target resistance change rate, it is possible to effectively obtain the lithium deposition detection results of the lithium battery online during the battery charging process.

[0009] In some implementations, the method further includes:

[0010] Determining a target stage charging time of the lithium battery in a preset stage of the charging process;

[0011] The step of determining the lithium deposition detection result of the lithium battery according to the target resistance change rate includes:

[0012] The lithium plating detection result of the lithium battery is determined according to the target resistance change rate and the target stage charging time.

[0013] In this implementation, the target stage charging time can also be used to effectively obtain the lithium deposition test result of the lithium battery online during the battery charging process. At the same time, based on the two parameters of the target resistance change rate and the target stage charging time, the lithium deposition test result of the lithium battery can be obtained more accurately online.

[0014] In some implementations, determining the lithium plating detection result of the lithium battery according to the target resistance change rate and the target stage charging duration includes:

[0015] Determine a target change rate range to which the target resistance change rate belongs in i change rate ranges set for the resistance change rate, where i is an integer greater than or equal to 1;

[0016] Determine the target duration range to which the target stage charging duration belongs in the i duration ranges set for the stage charging duration, wherein the i change rate ranges and the i duration ranges correspond one to one;

[0017] If the target change rate range corresponds to the target duration range, then it is determined that the lithium deposition detection result of the lithium battery is that lithium deposition occurs in the lithium battery.

[0018] In this implementation, the resistance change rate and the stage charging time are divided into multiple ranges to form range pairs, and then the target change rate range described by the target resistance change rate and the target time range described by the target stage charging time are judged to belong to the same range pair, thereby determining the lithium plating detection result. This can effectively broaden the judgment range for lithium plating detection and avoid missed detection of lithium plating.

[0019] In some implementations, the method further includes:

[0020] During the charging process of at least one sample lithium battery, obtaining a sample resistance change rate and a sample stage charging duration of each sample lithium battery, wherein the sample lithium battery is a lithium battery in which lithium deposition occurs;

[0021] According to the sample resistance change rate of each of the sample lithium batteries and the sample stage charging time, a lithium deposition parameter curve is fitted, and the lithium deposition parameter curve is used to reflect the mapping relationship between the stage charging time and the resistance change rate of the lithium battery where lithium deposition occurs.

[0022] In this implementation, a lithium deposition parameter curve is constructed by using sample parameters of multiple sample lithium batteries, wherein the lithium deposition parameter curve can reflect the mapping relationship between the stage charging time and the resistance change rate in the specific scenario of battery lithium deposition. Therefore, determining the lithium deposition detection result based on the lithium deposition parameter curve can effectively improve the accuracy of the result.

[0023] In some implementations, the method further includes:

[0024] Determine at least one change rate division value according to the corresponding relationship between the resistance change rate of the strain sensor and the bending degree of the protruding portion on the surface of the lithium battery;

[0025] Determine the i change rate ranges according to the at least one change rate partition value, wherein the endpoints of the change rate ranges are the change rate partition values;

[0026] Determine, according to the lithium deposition parameter curve, a time length division value corresponding to each of the at least one change rate division values;

[0027] The i duration ranges are determined according to at least one of the duration division values, and the endpoints of the duration ranges are the duration division values.

[0028] In this embodiment, the resistance change rate parameter division value is determined according to the corresponding relationship between the resistance change rate and the curvature of the lithium battery surface, so that multiple change rate ranges can be obtained according to the graded division for different lithium deposition severity. After that, the duration division value corresponding to the change rate division value is determined on the lithium deposition parameter curve, and the duration range is further obtained according to the duration division value, so as to ensure that the range pair obtained by division for determining the lithium deposition detection result conforms to the law of the lithium deposition parameter curve, so as to ensure the effectiveness and accuracy of determining the lithium deposition detection result according to the range pair.

[0029] In some implementations, obtaining a target resistance change rate of a strain sensor covered on a surface of the lithium battery during charging of the lithium battery includes:

[0030] Obtaining the real-time resistance of the strain sensor at a first full-charge moment, where the first full-charge moment is the moment when the lithium battery reaches a full-charge state during the charging process;

[0031] Obtaining an initial resistance of the strain sensor at an initial full-charge time, wherein the initial full-charge time is a time when the lithium battery reaches a full-charge state during the initial charging process;

[0032] A target resistance change rate of the strain sensor is determined according to the real-time resistance and the initial resistance.

[0033] In this embodiment, the target resistance change rate of the strain sensor is determined based on the real-time resistance at the first full-charge moment and the initial resistance at the initial full-charge moment, so that the resistance change rate can be obtained based on the entire life cycle of the lithium battery, thereby effectively improving the effectiveness of the changes in the surface deformation of the lithium battery reflected by the target resistance change rate.

[0034] In some implementations, obtaining the real-time resistance of the strain sensor at the first fully charged moment includes:

[0035] receiving a real-time sensor response sent by the strain sensor, wherein the real-time sensor response is a sensor response collected by the strain sensor at the first fully-charged moment;

[0036] The real-time resistance is determined based on the real-time sensor response.

[0037] In some implementations, the preset stage is a constant voltage charging stage;

[0038] The step of determining a target stage charging time of the lithium battery in a preset stage during the charging process includes:

[0039] Obtaining the first moment when the voltage of the lithium battery reaches the upper limit termination voltage;

[0040] Obtaining a second moment when the current of the lithium battery reaches a preset current;

[0041] According to the first moment and the second moment, a target stage charging duration of the constant voltage charging stage of the lithium battery in the charging process is determined.

[0042] In this implementation, the target stage charging time is obtained by the constant voltage charging stage for the lithium battery. Since the constant voltage charging stage is most sensitive to the lithium deposition phenomenon, it can be ensured that the target stage charging time can effectively reflect the lithium deposition situation.

[0043] In some implementations, obtaining the first moment when the voltage of the lithium battery reaches an upper limit termination voltage includes:

[0044] Receiving the first moment sent by a time point collector;

[0045] The obtaining of the second moment when the current of the lithium battery reaches a preset current includes:

[0046] The second moment sent by the receiving time point collector.

[0047] In some implementations, the method further includes:

[0048] For i range pairs consisting of the i change rate ranges and the corresponding i duration ranges, determining a processing strategy corresponding to each of the range pairs;

[0049] The processing strategy includes at least one of the following: no information prompt, prompt to update system software, prohibit charging and prompt to repair, prompt to shut down and prompt to repair.

[0050] In this implementation, by formulating different processing strategies for different ranges, it is possible to flexibly process different levels of lithium precipitation using different strategies.

[0051] In some implementations, the method further includes:

[0052] Obtaining a target early warning strategy corresponding to a range pair consisting of a target change rate range and a target duration range;

[0053] According to the target warning strategy, warning information is displayed on the screen of the terminal device corresponding to the lithium battery.

[0054] In this implementation, by displaying the warning information corresponding to the target warning strategy on the screen, the user can be informed of the specific situation of the lithium battery in a timely manner.

[0055] In a second aspect, an embodiment of the present application provides a battery lithium deposition detection device. The device comprises:

[0056] An acquisition module, used for acquiring a target resistance change rate of a strain sensor covered on the surface of the lithium battery during the charging process of the lithium battery;

[0057] A processing module is used to determine the lithium plating detection result of the lithium battery according to the target resistance change rate.

[0058] In some implementations, the processing module is further configured to:

[0059] Determining a target stage charging time of the lithium battery in a preset stage of the charging process;

[0060] The processing module is specifically used for:

[0061] The lithium plating detection result of the lithium battery is determined according to the target resistance change rate and the target stage charging time.

[0062] In some implementations, the specific module is also used to:

[0063] Determine a target change rate range to which the target resistance change rate belongs in i change rate ranges set for the resistance change rate, where i is an integer greater than or equal to 1;

[0064] Determine the target duration range to which the target stage charging duration belongs in the i duration ranges set for the stage charging duration, wherein the i change rate ranges and the i duration ranges correspond one to one;

[0065] If the target change rate range corresponds to the target duration range, then it is determined that the lithium deposition detection result of the lithium battery is that lithium deposition occurs in the lithium battery.

[0066] In some implementations, the processing module is further configured to:

[0067] During the charging process of at least one sample lithium battery, obtaining a sample resistance change rate and a sample stage charging duration of each sample lithium battery, wherein the sample lithium battery is a lithium battery in which lithium deposition occurs;

[0068] According to the sample resistance change rate of each of the sample lithium batteries and the sample stage charging time, a lithium deposition parameter curve is fitted, and the lithium deposition parameter curve is used to reflect the mapping relationship between the stage charging time and the resistance change rate of the lithium battery where lithium deposition occurs.

[0069] In some implementations, the processing module is further configured to:

[0070] Determine at least one change rate division value according to the corresponding relationship between the resistance change rate of the strain sensor and the bending degree of the protruding portion on the surface of the lithium battery;

[0071] Determine the i change rate ranges according to the at least one change rate partition value, wherein the endpoints of the change rate ranges are the change rate partition values;

[0072] Determine, according to the lithium deposition parameter curve, a time length division value corresponding to each of the at least one change rate division values;

[0073] The i duration ranges are determined according to at least one of the duration division values, and the endpoints of the duration ranges are the duration division values.

[0074] In some implementations, the acquisition module is specifically used to:

[0075] Obtaining the real-time resistance of the strain sensor at a first full-charge moment, where the first full-charge moment is the moment when the lithium battery reaches a full-charge state during the charging process;

[0076] Obtaining an initial resistance of the strain sensor at an initial full-charge time, wherein the initial full-charge time is a time when the lithium battery reaches a full-charge state during the initial charging process;

[0077] A target resistance change rate of the strain sensor is determined according to the real-time resistance and the initial resistance.

[0078] In some implementations, the acquisition module is specifically used to:

[0079] receiving a real-time sensor response sent by the strain sensor, wherein the real-time sensor response is a sensor response collected by the strain sensor at the first fully-charged moment;

[0080] The real-time resistance is determined based on the real-time sensor response.

[0081] In some implementations, the preset stage is a constant voltage charging stage;

[0082] The processing module is specifically used for:

[0083] Obtaining the first moment when the voltage of the lithium battery reaches the upper limit termination voltage;

[0084] Obtaining a second moment when the current of the lithium battery reaches a preset current;

[0085] According to the first moment and the second moment, a target stage charging duration of the constant voltage charging stage of the lithium battery in the charging process is determined.

[0086] In some implementations, the acquisition module is specifically used to:

[0087] Receiving the first moment sent by a time point collector;

[0088] The obtaining of the second moment when the current of the lithium battery reaches a preset current includes:

[0089] The second moment sent by the receiving time point collector.

[0090] In some implementations, the processing module is specifically configured to:

[0091] For i range pairs consisting of the i change rate ranges and the corresponding i duration ranges, determining a processing strategy corresponding to each of the range pairs;

[0092] The processing strategy includes at least one of the following: no information prompt, prompt to update system software, prohibit charging and prompt to repair, prompt to shut down and prompt to repair.

[0093] In some implementations, the processing module is further configured to:

[0094] Obtaining a target early warning strategy corresponding to a range pair consisting of a target change rate range and a target duration range;

[0095] According to the target warning strategy, warning information is displayed on the screen of the terminal device corresponding to the lithium battery.

[0096] In a third aspect, an embodiment of the present application provides a lithium battery, including: a battery body and a strain sensor;

[0097] Wherein, the strain sensor is attached to the surface of the battery body, and the strain sensor is used to detect the deformation of the surface of the battery body.

[0098] In some implementations, the battery body is provided with a positive terminal and a negative terminal;

[0099] One end of the strain sensor is connected to the positive terminal, and the other end of the strain sensor is connected to the negative terminal.

[0100] In some implementations, the strain sensor is a thin film strain sensor.

[0101] In a fourth aspect, an embodiment of the present application provides a terminal device, comprising: a lithium battery and a processor, wherein the lithium battery comprises a battery body and a strain sensor;

[0102] Wherein, the strain sensor is attached to the surface of the battery body, and the strain sensor is used to detect the deformation of the surface of the battery body;

[0103] The processor is configured to execute the method according to the first aspect.

[0104] In some implementations, the terminal device further includes: a time point collector;

[0105] The time point collector is used to collect at least one charging moment in the charging process of the lithium battery.

[0106] In some implementations, the strain sensor is connected to the processor via a first wire harness, and the strain sensor sends a sensor response to the processor via the first wire harness.

[0107] In some implementations, the time point collector is connected to the processor via a second wire harness, and the time point collector sends the collected charging time to the processor via the second wire harness.

[0108] In some implementations, the lithium battery is placed in a battery compartment area of ​​the terminal device.

[0109] In a fifth aspect, an embodiment of the present application provides a lithium deposition detection system, comprising: a lithium battery and a processor, wherein the lithium battery comprises a battery body and a strain sensor;

[0110] Wherein, the strain sensor is attached to the surface of the battery body, and the strain sensor is used to detect the deformation of the surface of the battery body;

[0111] The processor is configured to execute the method according to the first aspect.

[0112] In some implementations, the system further includes: a time point collector;

[0113] The time point collector is used to collect at least one charging moment in the charging process of the lithium battery.

[0114] In some implementations, the strain sensor is connected to the processor via a first wire harness, and the strain sensor sends a sensor response to the processor via the first wire harness.

[0115] In some implementations, the time point collector is connected to the processor via a second wire harness, and the time point collector sends the collected charging time to the processor via the second wire harness.

[0116] In some implementations, the system further includes: a screen;

[0117] The screen is used to display warning information.

[0118] In a sixth aspect, an embodiment of the present application provides a terminal device, which may also be referred to as a terminal, user equipment (UE), mobile station (MS), mobile terminal (MT), etc. The terminal device may be a mobile phone, a smart TV, a wearable device, a tablet computer (Pad), a computer with wireless transceiver function, a virtual reality (VR) terminal device, an augmented reality (AR) terminal device, a wireless terminal in industrial control, a wireless terminal in self-driving, a wireless terminal in remote medical surgery, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, etc.

[0119] The terminal device comprises: a processor and a memory; the memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory, so that the terminal device executes the method of the first aspect.

[0120] In a seventh aspect, an embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the method of the first aspect is implemented.

[0121] In an eighth aspect, an embodiment of the present application provides a computer program product, which includes a computer program. When the computer program is executed, the computer executes the method of the first aspect.

[0122] In a ninth aspect, an embodiment of the present application provides a chip, the chip including a processor, the processor being used to call a computer program in a memory to execute the method described in the first aspect.

[0123] It should be understood that the second to ninth aspects of the present application correspond to the technical solutions of the first aspect of the present application, and the beneficial effects achieved by each aspect and the corresponding feasible implementation methods are similar and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0124] Figure 1 A schematic diagram of the cross-sectional structure of a thin film strain sensor provided in an embodiment of the present application;

[0125] Figure 2 A schematic diagram of the working mechanism of the thin film strain sensor provided in an embodiment of the present application;

[0126] Figure 3 Schematic diagram of the arrangement of the thin film strain sensor provided in the embodiment of the present application Figure 1 ;

[0127] Figure 4 Schematic diagram of the arrangement of the thin film strain sensor provided in the embodiment of the present application Figure 2 ;

[0128] Figure 5 A schematic diagram of the structure of a terminal device provided in an embodiment of the present application;

[0129] Figure 6 A flow chart of a battery lithium deposition detection method provided in an embodiment of the present application;

[0130] Figure 7 The process of the battery lithium precipitation method provided in the embodiment of the present application Figure 2 ;

[0131] Figure 8 A schematic diagram of an implementation of determining a target resistance change rate provided in an embodiment of the present application;

[0132] Fig. 9 The process of the battery lithium deposition detection method provided in the embodiment of the present application Figure 3 ;

[0133] Fig.10 The lithium precipitation parameter curve provided in the embodiment of the present application;

[0134] Fig.11 A schematic diagram of the range pair and processing strategy provided in the embodiment of the present application;

[0135] Fig.12 A schematic diagram of an interface for displaying warning information provided in an embodiment of the present application;

[0136] Fig.13 Schematic diagram of lithium deposition detection provided in the embodiment of the present application Figure 1 ;

[0137] Fig.14 Schematic diagram of lithium deposition detection provided in the embodiment of the present application Figure 2 ;

[0138] Fig.15 A schematic diagram of the structure of a lithium deposition detection system provided in an embodiment of the present application;

[0139] Fig.16 A schematic diagram of the hardware architecture of a terminal device provided in an embodiment of the present application;

[0140] Fig.17 A schematic diagram of the structure of a battery lithium deposition detection device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0141] In order to facilitate the clear description of the technical solutions of the embodiments of the present application, in the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "exemplary" or "for example" in the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0142] In the embodiments of the present application, "at least one" refers to one or more, and "plurality" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0143] It should be noted that the "at..." in the embodiment of the present application can be the instant when a certain situation occurs, or a period of time after a certain situation occurs, and the embodiment of the present application does not specifically limit this. In addition, the display interface provided in the embodiment of the present application is only an example, and the display interface can also include more or less content.

[0144] In order to better understand the technical solution of the present application, the relevant technologies involved in the present application are further introduced in detail below.

[0145] Lithium batteries are widely used in electronic devices such as mobile phones, tablet computers, portable devices, and various electric vehicles such as electric cars and electric motorcycles due to their advantages of low pollution, high energy density, long cycle life and low self-discharge rate, becoming an indispensable component of these devices or vehicles. Therefore, the safety of lithium batteries has attracted more and more attention. Lithium deposition, as an abnormal phenomenon in the charging process of lithium batteries, has become one of the hot issues that people have paid attention to in recent years.

[0146] During the charging process of lithium batteries, lithium ions will be deintercalated from the positive electrode and embedded in the negative electrode. When the lithium ions deintercalated from the positive electrode cannot be embedded in the negative electrode, these lithium ions will precipitate on the surface of the negative electrode to form metallic lithium. This phenomenon is called lithium precipitation. The conditions for lithium precipitation can be divided into two types: internal factors and external factors. Internal factors usually include the negative electrode's potential to lithium being less than 0, which causes the lithium ions to no longer be fully embedded in the negative electrode, but part of them to be embedded in the negative electrode and part of them to be precipitated in the form of lithium metal. External factors usually include low temperature, high state of charge (SOC) and high rate charging. Among them, low temperature will slow down the diffusion of lithium ions, and the negative electrode's potential to lithium in a high charge state is relatively low, so that low temperature and high charge state are not conducive to the embedding of lithium ions in the negative electrode; high rate charging will generate a strong electric field to push a large number of lithium ions to be deintercalated from the positive electrode and embedded in the negative electrode. When the number of deintercalated lithium ions is greater than the number of lithium ions that the negative electrode can receive, lithium precipitation will occur. Therefore, if the lithium battery is discharged frequently for a long time to the point of being on the verge of shutdown (such as 3% SOC), and then recharged to the low power area (20% SOC), and then used in a cycle, or charged frequently in a low temperature environment, it is easy to cause rapid consumption of electrolyte or cause excessive temperature difference on the surface of the lithium battery, thus causing potential lithium deposition risks. Among them, SOC is the remaining power (State Of Charge).

[0147] Lithium deposition in lithium batteries will cause the thickness of lithium batteries to increase rapidly, significantly reducing the service life of lithium batteries. On the other hand, it will also limit the fast charging capacity of lithium batteries and may cause short circuits inside lithium batteries, leading to catastrophic consequences such as battery combustion and battery explosion.

[0148] Therefore, lithium plating of lithium batteries will have a serious impact on the service life and safety and reliability of lithium batteries. Therefore, it is particularly important to identify and accurately detect whether lithium plating occurs in lithium batteries as early as possible, and to judge the severity of lithium plating of lithium batteries.

[0149] At present, there are usually three methods for lithium deposition detection in related technologies:

[0150] One way is to disassemble the lithium battery when it is fully charged, and then determine whether lithium deposition has occurred in the lithium battery by observing the state of the lithium battery's electrodes.

[0151] This implementation method has the problems of long operation time and low efficiency, and the lithium battery must be separated from the electronic device separately and then disassembled before it can be determined whether lithium deposition has occurred in the lithium battery. As a result, it is impossible to perform real-time (or online) lithium deposition detection on the lithium battery, that is, it is impossible to perform lithium deposition detection during the use of the lithium battery. Therefore, the scope of application of this lithium deposition detection is very limited.

[0152] Another way to implement it is to build a reference electrode into the lithium battery, and then measure the real-time change of the potential of the negative electrode of the lithium battery through the reference electrode to determine whether the lithium battery can be shipped.

[0153] However, in this implementation, the reference electrode will interfere with the clicking process and have a negative impact on the measurement. In addition, the reference electrode will age during the battery charging cycle. Therefore, this implementation also has the problem of poor stability.

[0154] Another implementation method is to collect the battery thickness data during the lithium battery charge and discharge cycle, and then determine the baptism status of the lithium battery by drawing a thickness change rate curve. However, this implementation method requires the addition of high-precision thickness measurement equipment and pressure control modules, which will result in excessively high equipment costs and cannot be integrated into the limited space of the terminal device.

[0155] In response to the technical problems introduced above, the present application proposes the following technical concept: a thin film strain sensor with a wide measurement range and high sensitivity is pasted on the surface of a lithium battery. When lithium deposition occurs in the lithium battery, resulting in local expansion or local bulge, the thin film strain sensor will be stretched, thereby causing the impedance of the thin film strain sensor to change. Therefore, the impedance change of the thin film strain sensor can be detected during the battery charging process, thereby judging the lithium deposition state of the lithium battery online.

[0156] Let's first combine Figure 1 and Figure 2 The thin film strain sensor is described. Figure 1 A schematic diagram of the cross-sectional structure of a thin film strain sensor provided in an embodiment of the present application, Figure 2Schematic diagram of the working mechanism of the thin film strain sensor provided in an embodiment of the present application.

[0157] Figure 1 The schematic cross-sectional structure of the thin film strain sensor is shown in FIG. Figure 1 It can be confirmed that the thin film strain sensor includes a strain resistor coating, and the upper and lower layers of the strain resistor coating are covered with a flexible substrate, and the flexible substrate may be PET (polyethylene glycol terephthalate), for example.

[0158] And reference Figure 2 In the strain resistor layer, for example, a plurality of conductive units may be included, each of which includes multilayer graphene and nanometal materials. The nanometal materials are attached to the multilayer graphene and distributed around the multilayer graphene. The nanometal materials may be, for example, silver (Ag), platinum (Pt), gold (Au), and the like.

[0159] Figure 2 (a) shows the conductive path in the thin film strain sensor when it is not stretched. Figure 2 Indicated by the curved arrow in (a).

[0160] Then, assuming that the thin film strain sensor is stretched by 10%, then Figure 2 (b) When the stretching state is 10%, the distance between the conductive units in the thin film strain sensor is correspondingly pulled farther, so the conductive path of the thin film strain sensor will also change accordingly, becoming Figure 2 The path is shown by the curved arrow in (b).

[0161] Furthermore, assuming that the thin film strain sensor is stretched by 30%, then Figure 2 (c) When the stretching state is 30%, the distance between the conductive units in the thin film strain sensor is further extended, so the conductive path of the thin film strain sensor will also change accordingly, becoming Figure 2 The path is shown by the curved arrow in (c).

[0162] Therefore, refer to Figure 1 and Figure 2 What is certain is that the thin film strain sensor is a sensor that stretches in response to the force deformation of the measuring object, and after the thin film strain sensor is stretched, the conductive path therein will change, which in turn will affect the resistance.

[0163] Then, in the application scenario corresponding to the present application, the deformation of the surface of the lithium battery can be detected by a thin film strain sensor, and then the resistance change of the thin film strain sensor can be determined based on the stretching of the thin film strain sensor in response to the deformation of the surface of the lithium battery. For example, the lithium deposition situation of the lithium battery can be determined based on the resistance change.

[0164] In order to achieve the above purpose, it is necessary to cover the surface of the lithium battery with a thin film strain sensor. Figure 3 Understand the lithium battery provided by this application. Figure 3 Schematic diagram of the arrangement of the thin film strain sensor provided in the embodiment of the present application Figure 1 .

[0165] like Figure 3 As shown in (a), the lithium battery in the present application includes a battery body and a strain sensor.

[0166] The battery body may refer to the design and structure of any current lithium battery, and this embodiment does not impose any limitation on this.

[0167] The strain sensor is attached to the surface of the battery body and is used to detect the deformation of the surface of the battery body, or in other words, to detect the degree of deformation of the surface of the battery body.

[0168] Exemplarily, in order to ensure that the presence of the strain sensor does not affect the lithium battery itself, the strain sensor can be pasted on the surface of the packaging film of the battery body of the lithium battery. The packaging film is used to package the components inside the battery body as a whole, so as to obtain a complete and independent battery body. Therefore, pasting the strain sensor on the surface of the packaging film can ensure that the presence of the strain sensor does not affect the components inside the battery body. The pasting medium of the strain sensor on the surface of the battery body can be selected according to actual needs, and this embodiment does not limit this.

[0169] The deformation of the strain sensor itself will cause the conductive path therein to change, which in turn will cause the resistance to change. However, there is a prerequisite for detecting the resistance change caused by the deformation, that is, the strain sensor itself is powered.

[0170] like Figure 3 As shown in (a), a positive terminal and a negative terminal are usually provided on the battery body of the lithium battery, so one end of the strain sensor can be connected to the positive terminal, and the other end of the strain sensor can be connected to the negative terminal, so as to ensure that the strain sensor can be powered on, and then complete the subsequent corresponding detection.

[0171] and in Figure 3(b) shows another arrangement of the positive terminal and the negative terminal on the battery body of the lithium battery, which is similar to the connection method of the strain sensor and will not be repeated here.

[0172] The current embodiment describes that a strain sensor is attached to the surface of the battery body of a lithium battery to detect the deformation of the surface of the battery body. However, a practical problem is also involved in how to set the attachment position of the strain sensor.

[0173] For example, refer to Figure 3 (a) and Figure 3 (b) The strain sensor can be pasted in a rotating arrangement, that is, starting from the positive terminal or the negative terminal, the strain sensor is arranged in a straight line along a certain direction. When the end of this direction is reached, the strain sensor is arranged in a straight line in the opposite direction until the strain sensor can be arranged to reach the negative terminal or the positive terminal at the other end. In this implementation method, there are some gaps between every two adjacent straight lines.

[0174] This is a method of positioning the strain sensor, which can ensure that the battery area is covered as large as possible, while being able to more flexibly determine the position where the surface of the battery body is deformed.

[0175] Or, refer to Figure 4 There may be more ways to set up strain sensors. Figure 4 Schematic diagram of the arrangement of the thin film strain sensor provided in the embodiment of the present application Figure 2 .

[0176] like Figure 4 (a) The strain sensor can directly and completely cover the surface of the battery body, while still ensuring that the two ends of the strain sensor are connected to the positive terminal and the negative terminal respectively. In this implementation, it can be ensured that the deformation occurring at any position on the surface of the battery body can be accurately detected.

[0177] Or Figure 4 (b) The strain sensor can also cover only a part of the surface of the battery body, where the part can be, for example, an area where lithium deposition is likely to occur, or an artificially defined area, while still ensuring that the two ends of the strain sensor are connected to the positive terminal and the negative terminal respectively. In this implementation, the installation area of ​​the strain sensor can be effectively saved.

[0178] Or Figure 4(c) The strain sensor is also for a part of the surface area of ​​the battery body, but for this part of the area, the strain sensor is set in the rotation arrangement method described above, while still ensuring that the two sections of the strain sensor are connected to the positive terminal and the negative terminal respectively. In this implementation method, the setting area of ​​the strain sensor can be effectively saved, and at the same time, the position where the surface of the battery body is deformed can be determined more flexibly.

[0179] In addition to Figure 3 and Figure 4 In addition to the implementation methods described above, the specific location and arrangement of the strain sensor can also be selected and set according to actual needs, and this embodiment does not impose any special restrictions on this. It should also be noted that the length and width of the strain sensor can also be selected and set according to actual needs. For example, Figure 3 and Figure 4 The strain sensor connected between the positive terminal and the negative terminal may be a complete strain sensor, or may be composed of a plurality of strain sensors. This embodiment does not limit this, and a strain sensor of required length and width may be selected according to actual needs.

[0180] At the same time, the above Figure 3 and Figure 4 The above descriptions are all based on one surface of the battery body as an example. In the actual implementation process, the specific surfaces of the battery body on which the strain sensors are to be pasted can be selected and set according to actual needs. All surfaces that require strain sensors can adopt the above-described implementation method.

[0181] In the present application, the strain sensor may be, for example, the thin film strain sensor described above, wherein the film strain sensor is relatively thin, so that it can be ensured that the volume of the lithium battery itself is not affected, and thus it can be effectively integrated into electronic devices. Alternatively, in other possible implementations, other types of strain sensors may also be used to implement the technical solution of the present application, as long as the strain sensor meets the following characteristics: namely, the resistance change of the thin film strain sensor is determined in response to the stretching caused by the deformation of the surface of the lithium battery.

[0182] The above introduction is that the lithium battery includes a battery body and a strain sensor, that is, the battery body and the strain sensor are integrated into one, and together constitute the electronic component of the lithium battery. Or in other possible implementations, the original lithium battery can also be regarded as an independent electronic component, and the strain sensor can also be regarded as an independent electronic component, and then the strain sensor is attached to the surface of the lithium battery to achieve the purpose of this application. The implementation method is similar to the above introduction, but in this scenario, the lithium battery and the strain sensor are two independent components and are not integrated into one. The specific application scenario can be selected according to actual needs.

[0183] In this application, what is to be achieved is to perform online lithium deposition detection on lithium batteries, that is, to perform lithium deposition detection when the lithium battery is in the terminal device, so the following is combined with Figure 5 The relationship between terminal equipment and lithium batteries is explained. Figure 5 A schematic diagram of the structure of a terminal device provided in an embodiment of the present application.

[0184] like Figure 5 As shown, the terminal device may include a lithium battery and a processor 30 , and the lithium battery also includes the battery body 10 and the strain sensor 20 introduced in the above embodiment.

[0185] The strain sensor 20 is attached to the surface of the battery body 10, and the strain sensor 20 is used to detect the deformation of the surface of the battery body 10. Figure 5 In the figure, the mesh structure on the surface of the battery body 10 represents the attached strain sensor 20.

[0186] And, refer to Figure 5 It can be determined that the battery body 10 is placed in the battery compartment area 40, and the battery compartment area 40 is located in the device middle frame 50. For example, if the terminal device is a mobile phone, then the corresponding device middle frame 50 can be understood as a mobile phone middle frame.

[0187] The strain sensor 20 is connected to the processor via the first wiring harness 70 . The strain sensor 20 sends a sensor response to the processor 30 via the first wiring harness 70 . Then, the processor 30 can execute the lithium plating detection process according to the sensor response.

[0188] And reference Figure 5 The terminal device also includes a time point collector 60, which is used to collect at least one charging moment during the lithium battery charging process. Figure 5 The components of the time point collector 60 are not specifically shown, only its possible installation position is shown. In the actual implementation process, the specific implementation method and specific installation position of the time point collector 60 can be selected and set according to actual needs.

[0189] Furthermore, the time point collector 60 is connected to the processor 30 via the second wire harness 80, and the time point collector sends the collected charging time to the processor 30 via the second wire harness 80. Similarly, the processor 30 can execute the lithium deposition detection process according to the charging time.

[0190] Therefore, the execution subject of each embodiment in this application is the processor in the terminal device, where the processor can be a device with data processing function such as a CPU, a chip, a microprocessor, etc. Or at the software level, it can be understood that an edge computing platform is set in the terminal device, and the edge computing platform is used to undertake the work of lithium precipitation detection at the software level.

[0191] The battery lithium deposition detection method provided by the present application is described in detail below with reference to specific embodiments. Figure 6 A flow chart of a battery lithium deposition detection method provided in an embodiment of the present application.

[0192] like Figure 6 As shown, the method includes:

[0193] S601. During the charging process of the lithium battery, a target resistance change rate of a strain sensor covered on the surface of the lithium battery is obtained.

[0194] What is to be achieved in this embodiment is online lithium plating detection for lithium batteries. Based on the above introduction, it can be understood that lithium plating may occur during the charging process of lithium batteries. Therefore, in this embodiment, relevant data is obtained during the charging process of lithium batteries to perform subsequent lithium plating detection.

[0195] In this embodiment, the surface of the lithium battery is covered with a strain sensor, and more specifically, the surface of the battery body of the lithium battery is covered with the strain sensor in an adhesive manner. Based on the introduction of the above embodiment, it can be determined that the lithium battery and the strain sensor can be understood as being integrated into one device and together constitute a lithium battery. Alternatively, the lithium battery and the strain sensor can also be understood as two independent components, except that the strain sensor is adhesively covered on the surface of the lithium battery. This embodiment does not impose any special restrictions on specific application scenarios.

[0196] Furthermore, in each embodiment of the present application, the strain sensor can be understood as a thin film strain sensor, or other implementation methods can be expanded according to actual needs, as long as the strain sensor can meet the characteristics introduced above.

[0197] When lithium is deposited on a lithium battery, a bulge or bend will appear on the surface of the lithium battery where the lithium is deposited. Based on the above description, it can be determined that the strain sensor can detect the deformation on the surface of the lithium battery, so the strain sensor can detect the bulge or bend caused by lithium deposition.

[0198] Also, because the strain sensor is attached to the surface of the lithium battery, the local deformation of the lithium battery surface caused by lithium deposition will cause the strain sensor to stretch, and accordingly, the resistance corresponding to the conductive path inside the strain sensor will change.

[0199] Therefore, during the charging process of the lithium battery, the target resistance change rate of the strain sensor covered on the surface of the lithium battery can be obtained, wherein the target resistance change rate can effectively reflect the degree of deformation change on the surface of the lithium battery in the form of data.

[0200] Exemplarily, the target resistance change rate can be the change rate of the resistance corresponding to the strain sensor during the entire life cycle of the lithium battery (from the factory to the current moment). Alternatively, the target resistance change rate can also be the change rate of the resistance corresponding to the strain sensor during this charging process (from the moment of the charging period to the moment of the end of charging). The specific corresponding time period of the target resistance change rate can be selected according to actual needs, as long as it can reflect the degree of deformation of the lithium battery surface over a period of time.

[0201] S602: Determine a target charging duration of a preset stage in a charging process of the lithium battery.

[0202] When lithium plating occurs in a lithium battery, in addition to causing the surface of the lithium battery to bulge or bend, it will also affect the stage charging time of the lithium battery.

[0203] In addition, a complete charging process of a lithium battery usually has four stages, namely trickle charging stage, constant current charging stage, constant voltage charging node, and charging termination stage.

[0204] In order to more accurately monitor the stage charging time of the lithium battery, the target stage charging time of the lithium battery in the preset stage of this charging process can be determined, where the preset stage can include at least one of the following: trickle charging stage, constant current charging stage, constant voltage charging node, and charging termination stage.

[0205] That is to say, the stage charging duration of one or some stages in the charging process may be monitored, or the stage charging duration of all stages in the charging process may be monitored, and this embodiment does not impose any limitation on this.

[0206] Or in another possible implementation, the target stage charging time of the lithium battery in this charging process can be directly determined, that is, there is no need to determine the target stage charging time for each preset stage separately, which is also feasible.

[0207] It should be noted that step S602 is optional. When the solution is to determine the lithium plating detection result based on the target stage charging time, step S602 can be executed. When the solution is to determine the lithium plating detection result only based on the target resistance change rate, step S602 can be chosen not to be executed.

[0208] S603: Determine a lithium plating detection result of the lithium battery according to the target resistance change rate and / or the target stage charging time.

[0209] Because the target resistance change rate and the target stage charging time can reflect to a certain extent whether lithium plating occurs in the lithium battery, the lithium plating test result of the lithium battery can be determined according to the target resistance change rate and / or the target stage charging time. The lithium plating test result can indicate that lithium plating occurs in the lithium battery, or it can indicate that lithium plating does not occur in the lithium battery, which depends on the actual data obtained.

[0210] Among them, a single target resistance change rate can reflect the degree of change of the surface deformation of the lithium battery. For example, the target resistance change rate can be compared with the corresponding preset threshold value to determine the lithium deposition detection result of the lithium battery. Alternatively, the resistance change rate can be divided into multiple preset ranges, and the lithium deposition detection result of the lithium battery can be determined by determining the preset range to which the target resistance change rate belongs.

[0211] Similarly, a single target stage charging time can reflect the lithium deposition of the lithium battery to a certain extent. The longer the target stage charging time, the more likely it is that the lithium battery will deposit lithium, or the lithium deposition phenomenon may be more serious. For example, the target stage charging time can be compared with the corresponding preset threshold to determine the lithium deposition test result of the lithium battery. Alternatively, multiple preset ranges can be divided according to the stage charging time, and the lithium deposition test result of the lithium battery can be determined by determining the preset range to which the target stage charging time belongs.

[0212] Alternatively, the target resistance change rate and the target stage charging time may be combined to consider the two aspects and more accurately determine the lithium plating test result of the lithium battery.

[0213] The battery lithium deposition detection method provided in the embodiment of the present application includes: obtaining the target resistance change rate of the strain sensor covered on the surface of the lithium battery during the charging process of the lithium battery. According to the target resistance change rate, the lithium deposition detection result of the lithium battery is determined. By pasting the strain sensor on the surface of the lithium battery, when lithium deposition occurs in the lithium battery, the surface will be deformed, which will cause the conductive path in the strain sensor to change, and the corresponding resistance will be affected. Therefore, based on the target resistance change rate, it is possible to effectively obtain the lithium deposition detection result of the lithium battery online during the battery charging process.

[0214] It is also possible to determine the target stage charging time of the lithium battery in the preset stage of the charging process. The lithium deposition of the lithium battery will affect the stage charging time of the lithium battery in the preset stage. Therefore, the target stage charging time can also effectively achieve the online acquisition of the lithium deposition detection results of the lithium battery during the battery charging process. At the same time, based on the two parameters of the target resistance change rate and the target stage charging time, the lithium deposition detection results of the lithium battery can be obtained more accurately online.

[0215] Based on the above introduction, the following Figures 7 and 8 The implementation method of obtaining the target resistance change rate in the battery lithium deposition detection method provided in the present application is introduced. Figure 7 The process of the battery lithium precipitation method provided in the embodiment of the present application Figure 2 , Figure 8 A schematic diagram of an implementation of determining a target resistance change rate provided in an embodiment of the present application.

[0216] S701. Obtain the real-time resistance of the strain sensor at the first full-charge moment. The first full-charge moment is the moment when the lithium battery reaches a fully-charged state during the charging process.

[0217] During a charging process, if lithium plating continues to occur in a lithium battery, the deformation of the lithium battery surface will continue to change, and accordingly, the resistance corresponding to the strain sensor will continue to change. During a charging process, as charging continues, when the lithium battery reaches a full charge state, the lithium plating phenomenon is the most serious. In order to improve the effectiveness and sensitivity of the collected data to reflect the lithium plating phenomenon, the resistance of the strain sensor can be obtained when the lithium battery reaches a full charge state. At the same time, this can also effectively ensure that the most effective results are obtained based on the least data.

[0218] Therefore, the real-time resistance of the strain sensor at the first full-charge moment can be obtained, wherein the first full-charge moment is the moment when the lithium battery reaches the full-charge state during this charging process.

[0219] Based on the structure of the terminal device described above, it can be determined that each step in this embodiment is executed by the processor, wherein when the processor obtains the real-time resistance of the strain sensor at the first full-power moment, the strain sensor can collect the real-time sensor response at the first full-power moment, and then the strain sensor sends the real-time sensor response to the processor. The processor then determines the corresponding real-time resistance according to the real-time sensor response.

[0220] In one possible implementation, the real-time sensor response collected by the strain sensor can be the real-time pressure detected by it (the deformation of the lithium battery surface will generate pressure on the thin film strain sensor), and then the processor converts the real-time sensor response (i.e., real-time pressure) into an electrical signal to obtain the real-time resistance.

[0221] Alternatively, the real-time sensor response collected by the strain sensor can also be directly the real-time resistance, for example, the strain sensor itself can complete the operation of converting the real-time pressure into an electrical signal to obtain the real-time resistance. In this case, the processor can directly obtain the real-time resistance according to the real-time sensor response (real-time resistance) sent by the strain sensor.

[0222] The operation of converting pressure into an electrical signal to obtain resistance is specifically completed by a processor or a strain sensor, which can be selected and set according to actual needs.

[0223] S702, obtaining the initial resistance of the strain sensor at the initial full-charge time, where the initial full-charge time is the time when the lithium battery reaches a fully-charged state during the initial charging process.

[0224] When determining the resistance change rate, the longer the time span, the greater the degree of resistance change, and the more obvious the deformation of the lithium battery surface indicated by the corresponding resistance change rate. Therefore, in order to monitor the changes in the deformation of the lithium battery surface to the greatest extent, the resistance change rate of the strain sensor during the entire life cycle of the lithium battery can be directly obtained in this embodiment. Exemplarily, the initial resistance of the strain sensor at the initial full charge moment can be obtained, where the initial full charge moment is the moment when the lithium battery reaches a full charge state during the initial charging process.

[0225] For example, you can refer to Figure 8 To understand, such as Figure 8 As shown, for lithium batteries, the lithium batteries can be charged multiple times during the use of the terminal device. Figure 8 The n charging processes are illustrated in FIG.

[0226] During the initial charging of a lithium battery, it is assumed that the lithium battery Figure 8 The full charge state is reached at the time t1 indicated in the figure, then the time t1 can be determined as the initial full charge time, so the initial resistance of the strain sensor at the initial full charge time t1 can be obtained, for example, Figure 8 R1 is shown in FIG.

[0227] The implementation method of the processor obtaining the initial resistance of the strain sensor at the initial full-charge moment is similar to the implementation method of the processor obtaining the real-time resistance introduced in the above S701, and will not be repeated here.

[0228] S703 : Determine a target resistance change rate of the strain sensor according to the real-time resistance and the initial resistance.

[0229] After determining the real-time resistance and initial resistance described above, the target resistance change rate of the strain sensor can be determined based on the real-time resistance and initial resistance.

[0230] Next, combine Figure 8 The above example describes Figure 8 The t1 in the figure is the initial full-charge moment, and the initial resistance obtained at the initial full-charge moment t1 is R1.

[0231] At the same time, Figure 8 In the example, assume that the charging process is Figure 8 The nth charge is shown. During this charging process, the lithium battery Figure 8 The full charge state is reached at the time tn indicated in the figure, then the time tn can be determined as the first full charge time, and then the real-time resistance of the strain sensor at the first full charge time tn is obtained, for example, Figure 8 Rn shown in FIG.

[0232] Then the target resistance change rate of the strain sensor can be determined according to the real-time resistance Rn and the initial resistance R1. In a possible implementation, the resistance change rate can satisfy the following formula:

[0233]

[0234] Among them, R x This is the rate of change of resistance.

[0235] The method for determining the resistance change rate is not limited to the implementation of the above formula one. For example, adding a coefficient on the basis of the above formula one, or performing an identical deformation on the above formula one, can effectively determine the target resistance change rate of the strain sensor, as long as the resistance change rate is determined based on the real-time resistance and the initial resistance.

[0236] And it is also necessary to explain a special case. The real-time resistance and initial resistance introduced above are both the resistance of the strain sensor when the lithium battery is fully charged. However, in a charging process, the lithium battery may not be fully charged but the charging process is over (for example, the power is cut off). For this charging process, the resistance of the strain sensor at the moment of charging is completed, and then this resistance is used as the initial resistance or real-time resistance introduced above to perform the calculation introduced above. Alternatively, you can choose to ignore this charging process, that is, do not calculate the resistance change rate for this charging process, only collect data for the charging process when the lithium battery reaches a fully charged state, and then calculate the resistance change rate.

[0237] In the battery lithium deposition detection method provided in the embodiment of the present application, the real-time resistance of the strain sensor at the first full charge moment in the current charging process is obtained, and the initial resistance of the strain sensor at the initial full charge moment in the initial charging process is obtained, and then the target resistance change rate of the strain sensor is determined according to the real-time resistance and the initial resistance, so that the resistance change rate can be determined according to the resistance of the strain sensor over the longest time span, thereby improving the effectiveness of the resistance change rate in reflecting the degree of deformation of the battery surface. And the real-time resistance and the initial resistance in this embodiment correspond to the resistance of the strain sensor when the lithium battery is fully charged, so that the resistance can be obtained at the moment when the lithium deposition phenomenon is most serious during each charging process, so it can also be further ensured that the resistance change rate effectively reflects the lithium deposition of the battery.

[0238] Based on the above introduction, Fig. 9 The method for determining the charging time of the target stage is further described in detail. Fig. 9 The process of the battery lithium deposition detection method provided in the embodiment of the present application Figure 3 .

[0239] S901, obtaining the first moment when the voltage of the lithium battery reaches the upper limit termination voltage.

[0240] In this embodiment, it is necessary to obtain the target stage charging time of the preset stage in the charging process of the lithium battery. In a possible implementation method, the constant voltage charging stage can be selected as the preset stage, that is, only the target stage charging time of the constant voltage charging stage in the charging process of the lithium battery is obtained.

[0241] The reason why the constant voltage charging stage is selected as the preset stage is that the charging time of the constant voltage charging stage is the most sensitive to the lithium plating phenomenon of the lithium battery. That is to say, if lithium plating occurs in the lithium battery, it will have a greater impact on the charging time of the constant voltage charging stage. Therefore, by determining the target charging time of the constant voltage charging stage, the lithium plating situation of the battery can be most effectively reflected.

[0242] Here is a brief description of the constant voltage charging stage. For example, when the voltage of the lithium battery rises to 4.2V, the constant current charging ends and the constant voltage charging stage begins. The current is based on the saturation of the battery cell. As the charging process continues, the charging current slowly decreases from the maximum value. When it decreases to 0.01C, the charging is considered to be terminated, that is, the constant voltage charging stage ends, and the lithium battery is fully charged. The voltage rises to 4.2V and the current decreases to 0.01C introduced here are all exemplary descriptions. The specific values ​​can be set according to actual needs.

[0243] What can be determined is that when the voltage of the lithium battery rises to a specific value, the constant voltage charging stage begins, so the first moment when the voltage of the lithium battery reaches the upper limit termination voltage can be obtained, where the upper limit termination voltage can be, for example, the 4.2V introduced above, or any possible value can be set according to actual needs.

[0244] In one possible implementation, the time collector in the terminal device can perform time collection. When the voltage of the lithium battery reaches the upper limit termination voltage, the time collector can collect the first moment, and then the time collector sends the first moment to the processor, which thereby obtains the first moment.

[0245] Alternatively, the processor may also collect the first moment by itself, which is not limited in this embodiment.

[0246] S902, obtaining a second moment when the current of the lithium battery reaches a preset current.

[0247] And referring to the above introduction, it can be determined that after the constant voltage charging stage begins, the charging current of the battery will slowly decrease, and when the current decreases to a specific value, the constant voltage charging stage ends. Therefore, the second moment when the current of the lithium battery reaches the preset current can be obtained, where the preset current can be, for example, 0.01C as described above, or any possible value can be set according to actual needs.

[0248] Similarly, when the voltage of the lithium battery reaches the upper limit termination voltage, the time collector can collect the second moment, and then send the second moment to the processor, so that the processor obtains the second moment. Alternatively, the processor can collect the second moment by itself, which is not limited in this embodiment.

[0249] S903: Determine a target stage charging duration of a constant voltage charging stage during the charging process of the lithium battery according to the first moment and the second moment.

[0250] The first moment is the moment when the constant voltage charging stage begins, and the second moment is the moment when the constant voltage charging stage ends. Therefore, based on the first moment and the second moment, the target stage charging time of the constant source charging stage of the lithium battery in the charging process can be obtained.

[0251] In this embodiment, by obtaining the first moment when the voltage of the lithium battery reaches the upper limit termination voltage, and obtaining the second moment when the current of the lithium battery reaches the preset current, the first moment corresponds to the moment when the constant voltage charging stage begins, and the second moment corresponds to the moment when the constant voltage charging stage ends. Therefore, according to the first moment and the second moment, the target stage charging duration of the constant voltage charging stage can be simply and effectively obtained. In addition, the charging time can be collected simply and orderly through the time dot collector.

[0252] After determining the target resistance change rate and the target stage charging time, the lithium plating test results of the lithium battery can be determined based on these two data. Based on the above introduction, it can be determined that the lithium plating test results can be determined simply based on the target resistance change rate, or the lithium plating test results can be determined simply based on the target stage charging time. However, although both the target resistance change rate and the target stage charging time can reflect the lithium plating of the battery to a certain extent, these two data are not only affected by the lithium plating of the battery, other factors may also cause the target resistance change rate and the target stage charging time to change.

[0253] Then, in order to more accurately determine the lithium plating test results of lithium batteries, the lithium plating test results can be jointly determined based on the target resistance change rate and the target stage charging time. When lithium plating occurs in a lithium battery, on the one hand, the surface of the lithium battery will deform, causing the resistance of the strain sensor to change, and on the other hand, the stage charging time of the constant voltage charging stage will be extended. At the same time, the more serious the lithium plating phenomenon of the lithium battery, the greater the deformation of the surface of the lithium battery, the greater the corresponding resistance change of the strain sensor, and the longer the stage charging time of the constant voltage charging stage. Therefore, the lithium plating phenomenon of the lithium battery has a positive correlation with the two data of the resistance change rate and the stage charging time.

[0254] In order to more clearly indicate the lithium plating phenomenon by the two data of resistance change rate and stage charging time, a parameter correspondence between the resistance change rate and the stage charging time can be constructed based on at least one sample lithium battery in which lithium plating occurs.

[0255] In a possible implementation, multiple sample lithium batteries with lithium deposition may be collected, and then multiple cycles of charging may be performed on each of the sample lithium batteries. During the charging process for at least one sample lithium battery, the sample resistance change rate and the sample stage charging time of each sample lithium battery may be obtained.

[0256] Among them, the implementation method of determining the sample resistance change rate is similar to the implementation method of determining the target resistance change rate described above, and the implementation method of determining the sample stage charging time is similar to the implementation method of determining the target stage charging time described above, which will not be repeated here.

[0257] Afterwards, curve fitting is performed according to the sample resistance change rates and sample stage charging times collected respectively for multiple sample lithium batteries. Specifically, the sample resistance change rate and sample stage charging time collected once for a sample lithium battery can be used as a sample point, and then fitting is performed based on multiple sample points to obtain the fitted lithium plating parameter curve. The lithium plating parameter curve is used to reflect the mapping relationship between the stage charging time and the resistance change rate of the lithium battery where lithium plating occurs.

[0258] Among them, the lithium precipitation parameter curve obtained by fitting can be referred to, for example Fig.10 To understand, Fig.10 This is a lithium precipitation parameter curve provided in an embodiment of the present application.

[0259] like Fig.10 As shown, the horizontal axis is the stage charging time, the vertical axis is the resistance change rate, and the coordinate system is the lithium plating parameter curve.

[0260] It is understandable that because the lithium deposition parameter curve is obtained by fitting the data of multiple sample lithium batteries that have undergone lithium deposition, the lithium deposition parameter curve can reflect the mapping relationship between the stage charging time and the resistance change rate in a specific lithium deposition scenario. After that, the lithium deposition test results are determined according to the lithium deposition parameter curve, which can effectively ensure the accuracy of the lithium deposition test results, so as to exclude the resistance changes caused by the deformation of the lithium battery surface due to other reasons (such as battery gas production, bulging, deformation), and can exclude the changes in stage charging time due to other reasons (such as battery capacity reduction, charging cable wear, etc.).

[0261] In one possible implementation, the target resistance change rate (equivalent to Fig.10 The value on the ordinate of the target stage (equivalent to the value on the ordinate of the target stage) and the charging time of the target stage (equivalent to the value on the Fig.10 The value on the horizontal axis of the lithium deposition parameter curve) is located on the lithium deposition parameter curve. If it is located on the lithium deposition parameter curve, it can be confirmed that the current target resistance change rate and the target stage charging time meet the data characteristics of the lithium deposition scenario, and then the lithium deposition detection result can be confirmed that lithium deposition has occurred. Alternatively, if it is not located on the lithium deposition parameter curve, it can be confirmed that the current target resistance change rate and the target stage charging time do not meet the data characteristics of the lithium deposition scenario, and then the lithium deposition detection result can be confirmed that lithium deposition has not occurred.

[0262] However, by confirming whether the points corresponding to the target resistance change rate and the target stage charging time are located on the lithium deposition parameter curve, this condition is actually quite harsh, and the lithium deposition parameter curve is fitted based on multiple sample points (composed of sample resistance change rates and sample stage charging times). Therefore, in order to avoid missing the detection of lithium deposition phenomena, the division points can be determined on the lithium deposition parameter curve, and then the range pairs (including the range corresponding to the resistance change rate and the range corresponding to the stage charging time) can be determined based on the division points. Then, by judging whether the target resistance change rate and the target stage charging time are within the divided range pair, the lithium deposition detection result of the lithium battery can be determined.

[0263] In one possible implementation, there is a direct correspondence between the resistance change rate of the strain sensor and the degree of curvature of the raised portion on the surface of the lithium battery. Specifically, the more severe the lithium deposition phenomenon of the lithium battery is, the thicker the lithium deposition layer is. Correspondingly, the greater the curvature of the raised portion on the surface of the lithium battery is, the greater the resistance change rate on the strain sensor is.

[0264] Among them, the corresponding relationship between the resistance change rate and the degree of bending can be obtained, for example, by calibrating a variety of sample lithium batteries with different lithium deposition severity. Different degrees of bending correspond to different lithium deposition layer thicknesses and different lithium deposition severity. Therefore, the division range composed of each two adjacent change rate division values ​​can be understood as a level of severity corresponding to the lithium deposition phenomenon. Different processing strategies can be specified for different levels of severity.

[0265] In order to improve the rationality of the division range and specify corresponding processing strategies according to different severity levels, for example, at least one change rate division value can be determined based on the correspondence between the resistance change rate of the strain sensor and the bending degree of the protruding part of the lithium battery surface.

[0266] Alternatively, in order to facilitate data collection and data processing, the correspondence between the resistance of the strain sensor and the degree of bending can be determined, and then at least one change rate division value can be determined based on the correspondence between the resistance of the strain sensor and the degree of bending of the raised portion of the lithium battery surface.

[0267] For example, refer to Fig.11 To understand, Fig.11 A schematic diagram of the range pair and processing strategy provided in an embodiment of the present application.

[0268] like Fig.11 As shown, it is assumed that 4 change rate division values ​​are currently selected, namely 0, 100, 200, and 400.

[0269] Afterwards, i change rate ranges may be determined according to the selected at least one change rate partition value, and the endpoints of the change rate ranges are the change rate partition values.

[0270] Specifically, a change rate range can be determined according to every two adjacent change rate division values, referring to Fig.11 According to the four change rate division values, four change rate ranges can be determined. They are [0, 100), [100, 200), [200, 400), [400, +∞).

[0271] Furthermore, in this embodiment, some range pairs are divided based on the points on the lithium deposition parameter curve. Therefore, after determining i change rate ranges based on multiple change rate division values, the duration division value corresponding to at least one change rate division value can be further determined according to the lithium deposition parameter curve. This ensures that the change rate division value and the duration division value correspond to points on the lithium deposition parameter curve, thereby ensuring that the range pairs obtained by division can effectively measure whether there is lithium deposition in the lithium battery.

[0272] For example, combining Fig.10 and Fig.11 , for the selected 4 change rate division values, 0, 100, 200, 400. The stage charging time corresponding to the resistance change rate of 0 on the lithium deposition parameter curve is 6, the stage charging time corresponding to the resistance change rate of 100 on the lithium deposition parameter curve is 8, the stage charging time corresponding to the resistance change rate of 200 on the lithium deposition parameter curve is 10, and the stage charging time corresponding to the resistance change rate of 400 on the lithium deposition parameter curve is 12. Therefore, it can be confirmed that the time division values ​​corresponding to the 4 change rate division values ​​are 6, 8, 10, and 12 respectively.

[0273] Afterwards, i duration ranges can be determined according to at least one duration division value, and the endpoints of the duration ranges are the duration division values. It can be understood that the i change rate ranges and the i duration ranges in this embodiment are one-to-one corresponding, and respectively constitute i range pairs.

[0274] Specifically, a duration range can be determined based on every two adjacent duration division values, referring to Fig.11 According to the four duration division values, four duration ranges can be determined. They are [6, 8), [8, 10), [10, 12), and [12, +∞).

[0275] Based on the examples currently introduced, refer to Fig.10In fact, three division points are determined, and four range pairs are determined based on these three division points, namely, the range pair consisting of the change rate range [0, 100) and the duration range [6, 8), the range pair consisting of the change rate range [100, 200) and the duration range [8, 10), the range pair consisting of the change rate range [200, 400) and the duration range [10, 12), and the range pair consisting of the change rate range [400, +∞) and the duration range [12, +∞).

[0276] Then, when determining the lithium plating test result of the lithium battery based on the target resistance change rate and the target stage charging time, the target change rate range to which the target resistance change rate belongs can be determined within the i change rate ranges set for the resistance change rate, and the target time range to which the target stage charging time belongs can be determined within the i time ranges set for the stage charging time.

[0277] If the target change rate range corresponds to the target duration range (that is, they belong to the same range pair), it can be determined that the lithium plating test result of the lithium battery is that lithium plating has occurred in the lithium battery.

[0278] And based on the above introduction, it can be determined that each range pair corresponds to a level of severity of the lithium plating phenomenon, so different treatment strategies can be formulated for each range pair.

[0279] Specifically, for i range pairs consisting of the i change rate ranges and the corresponding i duration ranges, determining a processing strategy corresponding to each of the range pairs;

[0280] The processing strategy includes at least one of the following: no information prompt, prompt to update system software, prohibit charging and prompt for maintenance, prompt to shut down and prompt for maintenance.

[0281] For example, refer to Fig.11 For the range pair consisting of the change rate range [0, 100) and the duration range [6, 8), the corresponding processing strategy can be set to no warning, which means no information prompt. In this range, the lithium plating degree is actually very slight, so no information enhancement is required for the time being to avoid unnecessary interference to users.

[0282] And, for the range pair consisting of the change rate range [100, 200) and the duration range [8, 10), the corresponding processing strategy can be set to warning level 1, specifically, it means prompting to update the system software or update to the latest version. Among them, the degree of lithium plating corresponding to warning level 1 is also relatively mild. After the user updates the system software or upgrades the version, the battery data may be updated, thereby correcting the battery charging data to a certain extent.

[0283] And, for the range pair consisting of the change rate range [200, 400) and the duration range [10, 12), the corresponding processing strategy can be set to warning level 2, specifically prohibiting charging and prompting maintenance. Among them, the degree of lithium plating corresponding to warning level 2 can be understood as the degree that requires intervention, so the user can be prompted to prohibit further charging and prompt the user to repair.

[0284] Also, for the range pair consisting of the change rate range [400, +∞) and the duration range [12, +∞), the corresponding processing strategy can be set to warning level 3, specifically, prompting shutdown and maintenance. Under this strategy, because the lithium deposition phenomenon is serious and may be dangerous, it can also be forced to shut down after a preset time.

[0285] and in Fig.10 The corresponding processing strategies for the corresponding ranges are also indicated.

[0286] Based on the processing strategy introduced above, in this embodiment, the target warning strategy corresponding to the range consisting of the target change rate range and the target duration range can be obtained, and then the warning information is displayed on the screen of the terminal device corresponding to the lithium battery according to the target warning strategy.

[0287] For example, refer to Fig.12 To understand, Fig.12 A schematic diagram of an interface for displaying warning information provided in an embodiment of the present application.

[0288] If the target warning strategy is the warning level 1 described above, for example, the following may be displayed on the screen: Fig.12 (a) shows the warning message "Please update the system software to the latest version".

[0289] If the target warning strategy is the warning level 2 described above, for example, the following may be displayed on the screen: Fig.12 (b) The warning message shown is "Charging is prohibited, please send to the maintenance department for inspection."

[0290] If the target warning strategy is the warning level 3 described above, for example, the following may be displayed on the screen: Fig.12 (c) shows the warning message "Please turn off the machine (it will automatically turn off after z seconds), please send it to the maintenance department for inspection as soon as possible." Z is an integer greater than or equal to 1, and the specific selection can be made according to actual needs.

[0291] In the actual implementation process, the specific text content of the warning information corresponding to the target warning strategy displayed on the screen can be selected and set according to actual needs. This embodiment does not impose any restrictions on this, as long as it can express the content that the target warning strategy wants to express.

[0292] In this embodiment, by displaying the warning information corresponding to the target warning strategy on the screen of the terminal device, the user can be prompted to perform different degrees of operations according to the different degrees of lithium plating, so as to transmit the collected data, process the data, and feedback the information, and improve the timeliness of data analysis to warning, so as to timely remind the user of the lithium plating status of the lithium battery, so as to improve the transparency of the battery health status.

[0293] In the battery lithium deposition detection method provided in the embodiment of the present application, the sample resistance change rate and the sample stage charging time of multiple sample lithium batteries are collected, and then the lithium deposition parameter curve is fitted based on the multiple sample resistance change rates and the multiple sample stage charging time to obtain the relationship between the resistance change rate and the stage charging time under the specific phenomenon of lithium deposition. Then, based on the lithium deposition parameter curve, the lithium deposition detection result is determined according to the target resistance change rate and the target stage charging time, thereby effectively eliminating the battery surface deformation and stage charging time changes caused by other factors, and thus effectively ensuring the accuracy of the determined lithium deposition detection result.

[0294] And, when specifically determining the lithium deposition test result, in order to avoid missing the detection of battery lithium deposition, at least one division point can be determined on the lithium deposition parameter curve, and then i change rate ranges and i time ranges are obtained according to the change rate division value and duration division value corresponding to at least one division point, wherein the i change rate ranges and the i time ranges correspond to each other and respectively constitute i range pairs. Then, by judging whether the target resistance change rate and the target stage charging duration belong to the divided range pair, the lithium deposition test result is determined, so as to effectively broaden the judgment conditions for lithium deposition detection and avoid omissions.

[0295] Based on the content of the above embodiment, it should be noted that the above description is about determining the lithium deposition detection result of the lithium battery according to the target stage charging time and / or the target resistance change rate. As the lithium deposition phenomenon of the battery occurs, the stage charging time of the battery in the preset stage of the charging process may change. Therefore, in a possible implementation, the above target stage charging time can also be replaced by the parameter of the target time change rate.

[0296] Among them, the target duration change rate can be understood as the change rate of the stage charging duration of the lithium battery in the preset stage during the charging process, which is similar to the target resistance change rate. Exemplarily, the first stage charging duration of the lithium battery in the preset stage of this charging process can be obtained, and the second stage charging duration of the lithium battery in the preset stage during the initial charging process can be obtained, and then the target duration change rate is determined according to the first stage charging duration and the second stage charging duration.

[0297] Then, the target stage charging duration in each of the above embodiments is replaced by the target duration change rate, and the corresponding processing is performed, and the implementation method is similar. The lithium deposition parameter curve is also similar. When constructing the lithium deposition parameter curve, you can choose to collect the sample resistance change rate and the sample duration change rate to obtain the lithium deposition parameter curve. The lithium deposition parameter curve is used to reflect the mapping relationship between the resistance change rate and the duration change rate in the specific scenario of lithium deposition.

[0298] When determining the lithium plating detection result based on the target time change rate and / or the target resistance change rate, the implementation method is similar, except that the target time change rate can more accurately and effectively reflect the impact of the battery lithium plating phenomenon on the stage charging time of the preset stage.

[0299] Based on the above embodiments, when lithium deposition occurs on the surface of a lithium battery, there may be local lithium deposition in the form of dots or lines, and the strain sensor attached to the surface of the lithium battery can effectively detect the deposition. Fig.13 and Fig.14 Provide explanation. Fig.13 Schematic diagram of lithium deposition detection provided in the embodiment of the present application Figure 1 , Fig.14 Schematic diagram of lithium deposition detection provided in the embodiment of the present application Figure 2 .

[0300] like Fig.13 As shown in (a), assuming that the surface of the lithium battery has a point-like local lithium deposition at the position indicated by 1301, then the situation on the battery surface can be referred to Fig.13 (b), where the lithium battery 002 is located in the battery compartment 004, assuming that the point-shaped local lithium deposition indicated by 1301 corresponds to Fig.13 (b) shows the lithium precipitation area 001, then refer to Fig.13 (b) It can be confirmed that the thin film strain sensor 003 is stretched due to the convex deformation of the lithium deposition area 001, and then the resistance of the thin film strain sensor 003 changes. Therefore, the lithium deposition detection result can be effectively determined in real time based on the target resistance change rate.

[0301] As well as Fig.14 As shown in (a), assuming that the surface of the lithium battery has two positions indicated by 1401 and 1402, there are local lithium deposition lines, then the situation on the battery surface can be referred to Fig.14 (b), where the lithium battery 002 is located in the battery compartment 004, assuming that the linear local lithium deposition indicated by 1401 corresponds to Fig.14 (b) shows the lithium deposition area 005, and the linear local lithium deposition indicated by the assumption 1402 corresponds to Fig.14(b) shows the lithium precipitation area 006, then refer to Fig.14 (b) It can be confirmed that the thin film strain sensor 003 is stretched due to the convex deformation of the lithium deposition area 005 and the lithium deposition area 006, and then the resistance of the thin film strain sensor 003 changes. Therefore, the lithium deposition detection result can be effectively determined in real time based on the target resistance change rate.

[0302] Therefore, in the battery lithium deposition detection method provided in the embodiment of the present application, online lithium deposition detection can be effectively implemented for lithium deposition in various states.

[0303] The above embodiment introduces an implementation method in which a lithium battery, a strain sensor, a processor, and a time point collector are integrated in a terminal device, and an online lithium deposition detection is performed when the lithium battery is in the terminal device. In addition to this application scenario, the present application can also provide a lithium deposition detection system, in which each component in the lithium deposition detection system can be considered as an independent component, and based on the lithium deposition detection system, the lithium deposition detection result of the lithium battery can also be accurately and effectively determined.

[0304] Combine the following Fig.15 To explain, Fig.15 A schematic diagram of the structure of a lithium deposition detection system provided in an embodiment of the present application.

[0305] like Fig.15 As shown, the system includes: a lithium battery and a processor 1501, the lithium battery includes a battery body 1502 and a strain sensor 1503;

[0306] The strain sensor 1503 is attached to the surface of the battery body 1502, and the strain sensor 1503 is used to detect the deformation of the surface of the battery body 1502;

[0307] The processor 1501 is configured to execute the methods of the above embodiments.

[0308] And the system also includes: a time point collector 1504;

[0309] The time point collector 1504 is used to collect at least one charging moment in the charging process of the lithium battery.

[0310] The strain sensor 1503 is connected to the processor 1501 via a first wiring harness, and the strain sensor 1503 sends a sensor response to the processor 1501 via the first wiring harness.

[0311] Furthermore, the time point collector 1504 is connected to the processor 1501 via the second wire harness, and the time point collector 1504 sends the collected charging time to the processor 1501 via the second wire harness.

[0312] And, the system further includes: a screen 1507;

[0313] Screen 1507 is used to display the warning information corresponding to the target warning strategy. The specific method of determining the target warning strategy and the method of implementing the warning information can refer to the introduction of the above embodiment, which will not be repeated here.

[0314] Similar to the above-mentioned embodiments, the lithium plating detection system provided in the present application can conveniently and efficiently realize the determination of the lithium plating detection result of the battery, and based on the system, the online detection of lithium plating detection result described above can be realized, or, the offline lithium plating detection result of the separately disassembled lithium battery can also be performed, which can also accurately and efficiently complete the lithium plating detection.

[0315] In summary, the technical solution of this application can use advanced non-destructive testing technology to conduct real-time monitoring and early safety warning of lithium deposition in lithium-ion batteries throughout their life cycle, which has important practical application value for ensuring the best performance experience and safety of electronic product users. At the same time, by real-time monitoring of the strain changes of the thin film strain sensor and / or the stage charging time of the preset stage, it is possible to judge online whether the lithium-ion battery is depositing lithium, and the working process is simple, fast and efficient.

[0316] Based on the above embodiments, Fig.16 The hardware architecture of the terminal device provided in the embodiment of the present application is described. Fig.16 A schematic diagram of the hardware architecture of a terminal device provided in an embodiment of the present application.

[0317] As above Fig.16 As shown, the terminal device may include: a processor, an external memory interface, an internal memory, a Universal Serial Bus (USB) interface, a charging management module, a power management module, a battery, an antenna 1, an antenna 2, a mobile communication module, a wireless communication module, a sensor module, a button, a motor, an indicator, a camera, a display screen, and a Subscriber Identification Module (SIM) card interface, etc. The audio module may include a speaker, a receiver, a microphone, an earphone interface, etc., and the sensor module may include a pressure sensor, a gyroscope sensor, an air pressure sensor, a magnetic sensor, an acceleration sensor, a distance sensor, a proximity light sensor, a fingerprint sensor, a temperature sensor, a touch sensor, an ambient light sensor, a bone conduction sensor, etc.

[0318] In this embodiment, the battery can be understood as a lithium battery, and a strain sensor is attached to the surface of the lithium battery. Fig.16The lithium battery and the strain sensor may be understood to be integrated together or may be understood to be independent of each other, and this embodiment does not impose any particular limitation on this.

[0319] Wherein, the processor may include one or more processing units, for example: the processor may include an application processor (Application Processor, AP), a modem processor, a graphics processor (Graphics Processing Unit, GPU), an image signal processor (Image Signal Processor, ISP), a controller, a video codec, a digital signal processor (Digital Signal Processor, DSP), a baseband processor, and / or a neural network processor (Neural-network Processing Unit, NPU), etc. Wherein, different processing units can be independent devices or integrated in one or more processors. The processor is the nerve center and command center of the terminal device. The controller can generate an operation control signal according to the instruction opcode and the timing signal to complete the control of fetching and executing instructions. Wherein the processor can be used to execute each step in the battery lithium analysis detection method introduced in this application.

[0320] The internal memory can be used to store computer executable program codes, which include instructions. The processor executes various functional applications and data processing of the terminal device by running the instructions stored in the internal memory. For example, in an embodiment of the present application, the processor enables the terminal device to execute the battery lithium deposition detection method provided in the embodiment of the present application by running the instructions stored in the internal memory.

[0321] The terminal device realizes the display function through GPU, display screen, and application processor. GPU is a microprocessor for image processing, connecting the display screen and application processor. GPU is used to perform mathematical and geometric calculations for image rendering. The processor may include one or more GPUs, which execute program instructions to generate or change display information.

[0322] The display screen is used to display images, videos, etc. The display screen includes a display panel. The display panel can be a liquid crystal display (LCD), an organic light-emitting diode (OLED), an active-matrix organic light-emitting diode or an active-matrix organic light-emitting diode (AMOLED), a flexible light-emitting diode (FLED), Miniled, MicroLed, Micro-oled, a quantum dot light emitting diode (QLED), etc. In some embodiments, the terminal device may include 1 or N display screens, where N is a positive integer greater than 1. Among them, the display screen can be used to display the warning information introduced above.

[0323] A series of graphical user interfaces (GUIs) can be displayed on the display screen of a terminal device, and these GUIs are the main screens of the terminal device. Generally speaking, the size of the display screen of a terminal device is fixed, and only limited controls can be displayed on the display screen of the terminal device. A control is a GUI element, which is a software component included in an application program, and controls all data processed by the application program and interactive operations on the data. Users can interact with the control through direct manipulation to read or edit relevant information of the application program. Generally speaking, controls may include visual interface elements such as icons, buttons, menus, tabs, text boxes, dialog boxes, status bars, navigation bars, widgets, etc. For example, in an embodiment of the present application, the display screen may display warning prompt information.

[0324] The audio module is used to convert digital audio information into analog audio signal output, and is also used to convert analog audio input into digital audio signals. The audio module can also be used to encode and decode audio signals. In some embodiments, the audio module can be arranged in the processor, or some functional modules of the audio module can be arranged in the processor.

[0325] A speaker, also called a "horn", is used to convert audio electrical signals into sound signals. The terminal device can output warning prompt information through the speaker.

[0326] It is to be understood that the structure illustrated in the embodiments of the present application does not constitute a specific limitation on the terminal device. In other embodiments, the terminal device may include more or fewer components than shown in the figure, or combine certain components, or split certain components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

[0327] The operating system of the terminal device can adopt a layered architecture, an event-driven architecture, a micro-core architecture, a micro-service architecture, or a cloud architecture. The embodiment of the present application takes the Android system of the layered architecture as an example to illustrate the hardware and software structure of the terminal device. It should be noted that although the embodiment of the present application is illustrated by taking the Android system as an example, its basic principle is also applicable to terminal devices based on operating systems such as iOS or Windows.

[0328] The battery lithium deposition detection method of the embodiment of the present application has been described above, and the device for performing the above-mentioned battery lithium deposition detection method provided by the embodiment of the present application is described below. Those skilled in the art can understand that the method and the device can be combined and referenced with each other, and the relevant device provided by the embodiment of the present application can perform the steps in the above-mentioned battery lithium deposition detection method.

[0329] Fig.17 This is a schematic diagram of the structure of the battery lithium deposition detection device provided in the embodiment of the present application. Fig.17 As shown, the device 170 includes: an acquisition module 1701 and a processing module 1702;

[0330] The acquisition module 1701 is used to acquire the target resistance change rate of the strain sensor covered on the surface of the lithium battery during the charging process of the lithium battery;

[0331] The processing module 1702 is used to determine the lithium plating detection result of the lithium battery according to the target resistance change rate.

[0332] In some implementations, the processing module 1702 is further configured to:

[0333] Determining a target stage charging time of the lithium battery in a preset stage of the charging process;

[0334] The processing module 1702 is specifically used for:

[0335] The lithium plating detection result of the lithium battery is determined according to the target resistance change rate and the target stage charging time.

[0336] In some implementations, the specific module is also used to:

[0337] Determine a target change rate range to which the target resistance change rate belongs in i change rate ranges set for the resistance change rate, where i is an integer greater than or equal to 1;

[0338] Determine the target duration range to which the target stage charging duration belongs in the i duration ranges set for the stage charging duration, wherein the i change rate ranges and the i duration ranges correspond one to one;

[0339] If the target change rate range corresponds to the target duration range, then it is determined that the lithium deposition detection result of the lithium battery is that lithium deposition occurs in the lithium battery.

[0340] In some implementations, the processing module 1702 is further configured to:

[0341] During the charging process of at least one sample lithium battery, obtaining a sample resistance change rate and a sample stage charging duration of each sample lithium battery, wherein the sample lithium battery is a lithium battery in which lithium deposition occurs;

[0342] According to the sample resistance change rate of each of the sample lithium batteries and the sample stage charging time, a lithium deposition parameter curve is fitted, and the lithium deposition parameter curve is used to reflect the mapping relationship between the stage charging time and the resistance change rate of the lithium battery where lithium deposition occurs.

[0343] In some implementations, the processing module 1702 is further configured to:

[0344] Determine at least one change rate division value according to the corresponding relationship between the resistance change rate of the strain sensor and the bending degree of the protruding portion on the surface of the lithium battery;

[0345] Determine the i change rate ranges according to the at least one change rate partition value, wherein the endpoints of the change rate ranges are the change rate partition values;

[0346] Determine, according to the lithium deposition parameter curve, a time length division value corresponding to each of the at least one change rate division values;

[0347] The i duration ranges are determined according to at least one of the duration division values, and the endpoints of the duration ranges are the duration division values.

[0348] In some implementations, the acquisition module 1701 is specifically used to:

[0349] Obtaining the real-time resistance of the strain sensor at a first full-charge moment, where the first full-charge moment is the moment when the lithium battery reaches a full-charge state during the charging process;

[0350] Obtaining an initial resistance of the strain sensor at an initial full-charge time, wherein the initial full-charge time is a time when the lithium battery reaches a full-charge state during the initial charging process;

[0351] A target resistance change rate of the strain sensor is determined according to the real-time resistance and the initial resistance.

[0352] In some implementations, the acquisition module 1701 is specifically used to:

[0353] receiving a real-time sensor response sent by the strain sensor, wherein the real-time sensor response is a sensor response collected by the strain sensor at the first fully-charged moment;

[0354] The real-time resistance is determined based on the real-time sensor response.

[0355] In some implementations, the preset stage is a constant voltage charging stage;

[0356] The processing module 1702 is specifically used for:

[0357] Obtaining the first moment when the voltage of the lithium battery reaches the upper limit termination voltage;

[0358] Obtaining a second moment when the current of the lithium battery reaches a preset current;

[0359] According to the first moment and the second moment, a target stage charging duration of the constant voltage charging stage of the lithium battery in the charging process is determined.

[0360] In some implementations, the acquisition module 1701 is specifically used to:

[0361] Receiving the first moment sent by a time point collector;

[0362] The obtaining of the second moment when the current of the lithium battery reaches a preset current includes:

[0363] The second moment sent by the receiving time point collector.

[0364] In some implementations, the processing module 1702 is specifically configured to:

[0365] For i range pairs consisting of the i change rate ranges and the corresponding i duration ranges, determining a processing strategy corresponding to each of the range pairs;

[0366] The processing strategy includes at least one of the following: no information prompt, prompt to update system software, prohibit charging and prompt to repair, prompt to shut down and prompt to repair.

[0367] In some implementations, the processing module 1702 is further configured to:

[0368] Obtaining a target early warning strategy corresponding to a range pair consisting of a target change rate range and a target duration range;

[0369] According to the target warning strategy, warning information is displayed on the screen of the terminal device corresponding to the lithium battery.

[0370] The device provided in this embodiment can be used to execute the technical solution of the above method embodiment. Its implementation principle and technical effect are similar and will not be described in detail in this embodiment.

[0371] The battery lithium deposition detection method provided in the embodiment of the present application can be applied to electronic devices with communication functions. The electronic devices include terminal devices, and the specific device form of the terminal devices can refer to the above related descriptions, which will not be repeated here.

[0372] An embodiment of the present application provides a terminal device, which includes: a processor and a memory; the memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory, so that the terminal device executes the above method.

[0373] The embodiment of the present application provides a chip. The chip includes a processor, and the processor is used to call a computer program in a memory to execute the technical solution in the above embodiment. Its implementation principle and technical effect are similar to those of the above related embodiments, and will not be repeated here.

[0374] The embodiments of the present application also provide a computer-readable storage medium. The computer-readable storage medium stores a computer program. The above method is implemented when the computer program is executed by the processor. The method described in the above embodiment can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. If implemented in software, the function can be stored as one or more instructions or codes on a computer-readable medium or transmitted on a computer-readable medium. Computer-readable media can include computer storage media and communication media, and can also include any medium that can transfer a computer program from one place to another. The storage medium can be any target medium that can be accessed by a computer.

[0375] In one possible implementation, a computer-readable medium may include RAM, ROM, compact disc read-only memory (CD-ROM) or other optical disk storage, disk storage or other magnetic storage devices, or any other medium that is intended to carry or store the required program code in the form of instructions or data structures and can be accessed by a computer. Moreover, any connection is appropriately referred to as a computer-readable medium. For example, if a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) or wireless technology (such as infrared, radio and microwave) is used to transmit software from a website, server or other remote source, the coaxial cable, fiber optic cable, twisted pair, DSL or wireless technology such as infrared, radio and microwave are included in the definition of medium. Disks and optical disks as used herein include optical disks, laser disks, optical disks, digital versatile disks (DVD), floppy disks and Blu-ray disks, where disks usually reproduce data magnetically, while optical disks reproduce data optically using lasers. Combinations of the above should also be included in the scope of computer-readable media.

[0376] An embodiment of the present application provides a computer program product, which includes a computer program. When the computer program is executed, the computer executes the above method.

[0377] The embodiments of the present application are described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processing unit of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable device to generate a machine, so that the instructions executed by the processing unit of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0378] The above specific implementation methods further illustrate the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific implementation methods of the present invention and are not used to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made on the basis of the technical solutions of the present invention should be included in the protection scope of the present invention.

Claims

1. A battery lithium deposition detection method, characterized in that: include: During the charging process of the lithium battery, obtaining a target resistance change rate of the strain sensor covered on the surface of the lithium battery; The lithium plating detection result of the lithium battery is determined according to the target resistance change rate.

2. The method according to claim 1, characterized in that The method further comprises: Determining a target stage charging time of the lithium battery in a preset stage of the charging process; The step of determining the lithium deposition detection result of the lithium battery according to the target resistance change rate includes: The lithium plating detection result of the lithium battery is determined according to the target resistance change rate and the target stage charging time.

3. The method according to claim 1 or 2, characterized in that: The step of determining the lithium plating detection result of the lithium battery according to the target resistance change rate and the target stage charging duration includes: Determine a target change rate range to which the target resistance change rate belongs in i change rate ranges set for the resistance change rate, where i is an integer greater than or equal to 1; Determine the target duration range to which the target stage charging duration belongs in the i duration ranges set for the stage charging duration, wherein the i change rate ranges and the i duration ranges correspond one to one; If the target change rate range corresponds to the target duration range, then it is determined that the lithium deposition detection result of the lithium battery is that lithium deposition occurs in the lithium battery.

4. The method according to claim 3, characterized in that The method further comprises: During the charging process of at least one sample lithium battery, obtaining a sample resistance change rate and a sample stage charging time of each sample lithium battery, wherein the sample lithium battery is a lithium battery in which lithium deposition occurs; According to the sample resistance change rate of each of the sample lithium batteries and the sample stage charging time, a lithium deposition parameter curve is fitted, and the lithium deposition parameter curve is used to reflect the mapping relationship between the stage charging time and the resistance change rate of the lithium battery where lithium deposition occurs.

5. The method according to claim 4, characterized in that The method further comprises: Determine at least one change rate division value according to the corresponding relationship between the resistance change rate of the strain sensor and the bending degree of the protruding portion on the surface of the lithium battery; Determine the i change rate ranges according to the at least one change rate partition value, wherein the endpoints of the change rate ranges are the change rate partition values; Determine, according to the lithium deposition parameter curve, a time length division value corresponding to each of the at least one change rate division values; The i duration ranges are determined according to at least one of the duration division values, and the endpoints of the duration ranges are the duration division values.

6. The method according to any one of claims 1 to 5, characterized in that: During the charging process of the lithium battery, obtaining a target resistance change rate of the strain sensor covered on the surface of the lithium battery includes: Obtaining the real-time resistance of the strain sensor at a first full-charge moment, where the first full-charge moment is the moment when the lithium battery reaches a full-charge state during the charging process; Obtaining an initial resistance of the strain sensor at an initial full-charge time, wherein the initial full-charge time is a time when the lithium battery reaches a full-charge state during the initial charging process; A target resistance change rate of the strain sensor is determined according to the real-time resistance and the initial resistance.

7. The method according to claim 6, characterized in that The obtaining of the real-time resistance of the strain sensor at the first fully charged moment includes: receiving a real-time sensor response sent by the strain sensor, wherein the real-time sensor response is a sensor response collected by the strain sensor at the first fully-charged moment; The real-time resistance is determined based on the real-time sensor response.

8. The method according to any one of claims 1 to 7, characterized in that: The preset stage is a constant voltage charging stage; The step of determining a target stage charging time of the lithium battery in a preset stage during the charging process includes: Obtaining the first moment when the voltage of the lithium battery reaches the upper limit termination voltage; Obtaining a second moment when the current of the lithium battery reaches a preset current; According to the first moment and the second moment, a target stage charging duration of the constant voltage charging stage of the lithium battery in the charging process is determined.

9. The method according to claim 8, characterized in that The obtaining of the first moment when the voltage of the lithium battery reaches the upper limit termination voltage comprises: Receiving the first moment sent by a time point collector; The obtaining of the second moment when the current of the lithium battery reaches a preset current includes: The second moment sent by the receiving time point collector.

10. The method according to claim 8 or 9, characterized in that: The method further comprises: For i range pairs consisting of the i change rate ranges and the corresponding i duration ranges, determining a processing strategy corresponding to each of the range pairs; The processing strategy includes at least one of the following: no information prompt, prompt to update system software, prohibit charging and prompt to repair, prompt to shut down and prompt to repair.

11. The method according to claim 10, characterized in that The method further comprises: Obtaining a target early warning strategy corresponding to a range pair consisting of a target change rate range and a target duration range; According to the target warning strategy, warning information is displayed on the screen of the terminal device corresponding to the lithium battery.

12. A lithium battery, characterized in that: include: Battery body and strain sensor; Wherein, the strain sensor is attached to the surface of the battery body, and the strain sensor is used to detect the deformation of the surface of the battery body.

13. The lithium battery according to claim 12, characterized in that: The battery body is provided with a positive terminal and a negative terminal; One end of the strain sensor is connected to the positive terminal, and the other end of the strain sensor is connected to the negative terminal.

14. The lithium battery according to claim 12 or 13, characterized in that: The strain sensor is a thin film strain sensor.

15. A terminal device, characterized in that: include: A lithium battery and a processor, wherein the lithium battery includes a battery body and a strain sensor; Wherein, the strain sensor is attached to the surface of the battery body, and the strain sensor is used to detect the deformation of the surface of the battery body; The processor is configured to execute the method according to any one of claims 1 to 11.

16. The terminal device according to claim 15, characterized in that: The terminal device also includes: a time point collector; The time point collector is used to collect at least one charging moment in the charging process of the lithium battery.

17. The terminal device according to claim 15, characterized in that: The strain sensor is connected to the processor via a first wire harness, and the strain sensor sends a sensor response to the processor via the first wire harness.

18. The terminal device according to claim 16, characterized in that: The time point collector is connected to the processor via a second wire harness, and the time point collector sends the collected charging time to the processor via the second wire harness.

19. The terminal device according to any one of claims 15 to 18, characterized in that: The lithium battery is placed in the battery compartment area of ​​the terminal device.

20. A lithium deposition detection system, characterized in that: include: A lithium battery and a processor, wherein the lithium battery includes a battery body and a strain sensor; Wherein, the strain sensor is attached to the surface of the battery body, and the strain sensor is used to detect the deformation of the surface of the battery body; The processor is configured to execute the method according to any one of claims 1 to 11.

21. The system according to claim 20, characterized in that The system also includes: a time point collector; The time point collector is used to collect at least one charging moment in the charging process of the lithium battery.

22. The system according to claim 21, characterized in that The strain sensor is connected to the processor via a first wire harness, and the strain sensor sends a sensor response to the processor via the first wire harness.

23. The system according to claim 22, characterized in that The time point collector is connected to the processor via a second wire harness, and the time point collector sends the collected charging time to the processor via the second wire harness.

24. The system according to claim 20, characterized in that The system further comprises: a screen; The screen is used to display warning information.

25. A terminal device, characterized in that: include: Processor and memory; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory, so that the terminal device executes the method according to any one of claims 1 to 11.

26. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 11 is implemented.

27. A computer program product, characterized in that The invention comprises a computer program, which, when being executed, enables a computer to execute the method according to any one of claims 1 to 11.

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