Battery self-discharge testing method, system and apparatus

Abstract

A battery self-discharge testing method, system and apparatus. According to the method, during determination of a voltage drop of a battery, the battery is connected in parallel to an external resistor with specific resistance for a certain duration, and then self-discharge testing of the battery is completed on the basis of a voltage drop result after the parallel connection. Therefore, the effect of accelerating a battery discharge process by reducing the parallel connection resistance of a circuit, so as to shorten a battery voltage drop acquisition duration is achieved. Therefore, the problem in the related art of long battery self-discharge testing time caused by a battery needing to undergo long time standing to achieve the measurement of a reliable voltage drop when the battery has a large capacity or a testing instrument has a low precision standard is alleviated.

Description

Method, system and device for testing battery self-discharge

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application No. 202311639065.6, filed on December 4, 2023, entitled “Method, system and device for testing battery self-discharge,” the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present application relates to the field of battery technology, and in particular to a method, system, and device for testing battery self-discharge. Background Art

[0004] Lithium-ion batteries have become the main power source for modern electric devices due to their advantages of high energy and high power density.

[0005] In related technologies, when conducting self-discharge tests on lithium-ion batteries, professionals typically measure the battery's voltage drop. However, when the battery capacity is large or the test instrument's accuracy is low, a long rest period is often required to reliably measure the voltage drop, which increases the test time.

[0006] It should be noted that the above statements are only used to provide background technical information related to this application and do not necessarily constitute prior art.

[0007] Summary of the Invention

[0008] The embodiments of the present application provide a method, system, and device for testing battery self-discharge, thereby alleviating the problem in related arts that determining the battery voltage drop takes a long time, which results in a long battery self-discharge test time.

[0009] According to one aspect of an embodiment of the present application, a method for testing battery self-discharge is provided, comprising:

[0010] Based on the electrical parameters of the battery to be tested, an external resistance value and an external connection time are calculated; a parallel operation for the external connection time is performed on the battery to be tested, wherein the parallel operation is used to connect the battery to be tested in parallel with an external resistor of the external resistance value; a voltage drop of the battery to be tested obtained by the parallel operation is determined, and based on the voltage drop, a self-discharge result of the battery to be tested is calculated.

[0011] By applying the technical solution of the embodiment of the present application, in the process of determining the voltage drop of the battery, it is possible to choose to connect it in parallel with an external resistor of a specific resistance for a certain period of time, and then complete the self-discharge test of the battery based on the voltage drop result after the parallel connection. Thereby achieving a method of accelerating the battery discharge process by reducing the parallel resistance of the circuit, thereby shortening the time it takes to obtain the battery voltage drop. Thereby alleviating the problem that occurs in the related art, when the capacity of the battery is large or the accuracy standard of the test instrument is low, the battery needs to be left to stand for a long time before a reliable voltage drop can be measured, resulting in a long self-discharge time of the test battery.

[0012] Optionally, in another embodiment based on the above method of the present application, the external resistance is calculated based on the electrical parameters of the battery to be tested, including: determining the external resistance limit value based on the self-discharge rate limit value of the battery to be tested; and using a target resistance value that is less than the external resistance limit value as the external resistance value. By applying the technical solution of the embodiment of the present application, the maximum resistance value of the resistor to be connected in parallel with the battery can be first determined based on the self-discharge rate limit value of the battery, so that an external resistor that is less than the maximum resistance value can be subsequently connected in parallel with the external resistor. This alleviates the disadvantage that when the external resistance of the external resistor is too large, the voltage difference between the battery to be tested and the external resistor is large, which causes the external resistor to suppress the discharge of the battery to be tested.

[0013] Optionally, in another embodiment of the above-mentioned method of the present application, based on the self-discharge rate limit value of the battery to be tested, the external resistance limit value is determined, including: based on the self-discharge rate limit value of the battery to be tested and the battery capacity, the self-discharge current limit value of the battery to be tested is calculated; and, a first open-circuit voltage value of the battery to be tested is obtained; based on the self-discharge current limit value and the first open-circuit voltage value, the external resistance limit value is calculated. By applying the technical solution of the embodiment of the present application, the maximum resistance value of the resistor connected in parallel to the battery can be further determined based on the self-discharge rate limit value of the battery and the battery capacity, so that an external resistor smaller than the maximum resistance value is subsequently connected in parallel with the external resistor. This alleviates the disadvantage that when the external resistance value of the external resistor is too large, the voltage difference between the battery to be tested and the external resistor is large, which causes the external resistor to suppress the discharge of the battery to be tested.

[0014] Optionally, based on the electrical parameters of the battery to be tested, the external connection time is calculated, including: calculating the parallel resistance value corresponding to the parallel operation based on the external resistance value and the internal resistance of the battery to be tested; calculating the ratio of the preset voltage change to the parallel resistance value, and using the ratio as the sample self-discharge current of the battery to be tested; the preset voltage change is the minimum voltage change that can be measured by the voltage measurement module; determining the sample charge change of the battery to be tested when the sample voltage change reaches the preset voltage change; and calculating the external connection time based on the sample charge change and the sample self-discharge current. By applying the technical solution of the embodiment of the present application, the degree of change in the charge capacity that the battery to be tested can achieve during the parallel operation can be calculated based on the parallel resistance value and the minimum voltage change of the parallel system, and the most appropriate external connection time for connecting it in parallel can be determined based on the degree of change, so that the battery to be tested can be subsequently operated in parallel based on the external connection time. This alleviates the problem that when the external connection time of the parallel connection is too long, the waiting time for obtaining the battery voltage drop will be unnecessarily increased, thereby increasing the self-discharge test time.

[0015] Optionally, in another embodiment of the above method based on the present application, determining the amount of charge change of the battery to be tested when the sample voltage change reaches the preset voltage change includes: obtaining a preset numerical correlation relationship for reflecting the amount of charge change and the voltage change of the battery to be tested; based on the sample voltage change, querying and obtaining the sample amount of charge change of the battery to be tested from the numerical correlation relationship. By applying the technical solution of the embodiment of the present application, in the process of determining the most suitable external connection time for connecting the battery to be tested in parallel, the degree of change in voltage capacity can be determined based on the preset numerical correlation relationship and the degree of change in the charge capacity that the battery can achieve during the parallel operation, so that the most suitable external connection time for connecting the battery to be tested in parallel can be determined based on the degree of change in the voltage capacity. This alleviates the problem of increasing the self-discharge test time due to the unnecessary increase in the waiting time for obtaining the battery voltage drop when the external connection time of the parallel connection is too long.

[0016] Optionally, in another embodiment based on the above-mentioned method of the present application, the parallel operation for the external connection time is performed on the battery to be tested, including: obtaining a test instruction for performing self-discharge processing on the battery to be tested, determining a preset temperature and humidity environment based on the battery material and current electrical performance indicators of the battery to be tested; and performing the parallel operation for the external connection time on the battery to be tested under the preset temperature and humidity environment. By applying the technical solution of the embodiment of the present application, before connecting the batteries in parallel, it is possible to first select a temperature and humidity environment that can best achieve its rapid discharge effect based on the electrical performance indicators of the battery. This allows the battery to be subsequently subjected to a parallel operation for the external connection time in this temperature and humidity environment. This further accelerates the battery discharge process and shortens the battery voltage drop acquisition time.

[0017] Optionally, in another embodiment of the method described above, determining the voltage drop of the battery to be tested obtained by the parallel operation includes: obtaining a first open-circuit voltage value of the battery to be tested before the parallel operation is performed; and obtaining a second open-circuit voltage value of the battery to be tested after the parallel operation is performed; and obtaining the voltage drop of the battery to be tested based on the first open-circuit voltage value and the second open-circuit voltage value. By applying the technical solution of the embodiment of the present application, in the process of determining the voltage drop of the battery, the voltage drop result can be calculated based on the two open-circuit voltage values ​​of the battery before and after the parallel connection, so that the self-discharge test of the battery can be completed based on the voltage drop result. This achieves a method of accelerating the battery discharge process by reducing the parallel resistance of the circuit, thereby shortening the time it takes to obtain the battery voltage drop. This alleviates the problem in the related art that when the battery capacity is large or the accuracy standard of the test instrument is low, the battery needs to be left to stand for a long time before a reliable voltage drop can be measured, resulting in a long self-discharge time of the test battery.

[0018] Optionally, the self-discharge result of the battery to be tested is calculated based on the voltage drop, including: calculating the self-discharge result of the battery to be tested based on the voltage drop and the external resistance. By applying the technical solution of the embodiment of the present application, in the process of determining the voltage drop of the battery, the voltage drop result can be calculated based on the two open-circuit voltage values ​​of the battery before and after parallel connection, so that the self-discharge test of the battery can be completed based on the voltage drop result and the resistance value of the external resistor. Thereby, a method of accelerating the battery discharge process by reducing the parallel resistance of the circuit is achieved, thereby shortening the battery voltage drop acquisition time.

[0019] Among them, according to one aspect of an embodiment of the present application, a system for testing battery self-discharge is provided, including a voltage measurement module, a parallel resistance module, a battery access device and a processing device; the voltage measurement module is connected to the processing device; the battery access device is used to connect to a battery to be tested, and is used to connect to the voltage measurement module in a first state to form a voltage measurement loop, and to connect to the parallel resistance module in a second state to form a self-discharge loop.

[0020] By applying the technical solution of the embodiment of the present application, a system for automatically connecting the batteries to be tested in parallel can be realized by using a voltage measurement module, a parallel resistance module, a battery access device, and a processing device. This can further achieve an effect of accelerating the battery discharge process by reducing the parallel resistance of the circuit, thereby shortening the battery voltage drop acquisition time. This can alleviate the problem of a long self-discharge time of the test battery caused by the need to let the battery rest for a long time before a reliable voltage drop can be measured in the related art when the battery capacity is large or the accuracy standard of the test instrument is low.

[0021] Optionally, the parallel resistance module includes at least one parallel branch; the parallel branch includes a first external port, a second external port and at least one resistor, one end of the circuit formed by the at least one resistor is connected to the first external port, and the other end of the circuit is connected to the second external port; the first external ports of each parallel branch are independent of each other, and the second external ports of each parallel branch are independent of each other; the first external port and the second external port are respectively used to connect the positive terminal and the negative terminal of the battery access device. By applying the technical solution of the embodiment of the present application, a parallel branch including multiple external ports can be used to realize the function of automatically opening and closing the parallel connection of the battery to be tested. Then, a method of connecting the external resistor to the positive and negative terminals of the battery in a manner of mutual manipulation of multiple external ports is realized to achieve the effect of reducing the parallel resistance of the circuit.

[0022] Optionally, the parallel resistance module includes at least one parallel branch; the parallel branch includes a first external port, a second external port and at least one resistor, one end of the circuit formed by the at least one resistor is connected to the first external port, and the other end of the circuit is connected to the second external port; the first external ports of each parallel branch are independent of each other, and the second external ports of each parallel branch are independent of each other; the first external port and the second external port are respectively used to connect to the positive terminal and the negative terminal of the battery access device. By applying the technical solution of the embodiment of the present application, a voltage measurement module including a code scanning element, a measuring element, a first port and a second port can be used to measure the open circuit voltage value of the battery before and after parallel connection, and the voltage value can be associated with the battery identification obtained by scanning the code scanning element, so that the voltage drop result of the battery can be obtained later.

[0023] Optionally, the voltage measurement module includes a code scanning element, a measuring element, a first port, and a second port; the code scanning element and the measuring element are connected in parallel between the first port and the second port, and the first port and the second port are respectively used to connect to the positive terminal and the negative terminal of the battery access device; the code scanning element and the measuring element are both connected to the processing device. By applying the technical solution of the embodiment of the present application, a battery access device including a first switch, a second switch, a positive connection terminal, and a negative connection terminal can be used to measure the open circuit voltage value of the battery before and after parallel connection, thereby realizing a method of connecting an external resistor to the positive and negative terminals of the battery in a manner that multiple external ports are mutually controlled to achieve the effect of reducing the parallel resistance of the circuit.

[0024] Optionally, the battery access device includes a first switch, a second switch, a positive connection terminal and a negative connection terminal; the positive connection terminal and the negative connection terminal are respectively used to connect the positive and negative poles of the battery to be tested; one end of the first switch is connected to the positive connection terminal, and the other end of the first switch is used to switch the connection between the positive end of the voltage measurement module or the positive end of the parallel resistance module; one end of the second switch is connected to the negative connection terminal, and the other end of the second switch is used to switch the connection between the negative end of the voltage measurement module or the negative end of the parallel resistance module. By applying the technical solution of the embodiment of the present application, a battery access device including a first switch, a second switch, a positive connection terminal and a negative connection terminal can be used to measure the open circuit voltage value of the battery before and after parallel connection, thereby realizing a method of connecting the external resistor to the positive and negative ends of the battery in a manner of mutual manipulation of multiple external ports to achieve the effect of reducing the parallel resistance of the circuit.

[0025] Optionally, the system further includes a transmission mechanism; the battery access device is provided on the transmission mechanism, and the transmission mechanism is connected to the processing device; the processing device is used to control the transmission mechanism to drive the battery access device to move toward the voltage measurement module in the first state, and to control the transmission mechanism to drive the battery access device to move toward the parallel resistance module in the second state. By applying the technical solution of the embodiment of the present application, the transmission mechanism can be used to realize the connection and separation function of the measuring battery and the external resistor. Thereby, a self-discharge system is realized that can automatically connect the batteries to be tested in parallel when a start-up command is detected, thereby reducing the parallel resistance of the circuit.

[0026] Optionally, the conveying mechanism includes a bracket and a conveyor belt; the bracket is arranged between the voltage measuring module and the parallel resistance module; the battery access device is slidably connected to the bracket, and the conveyor belt is fixedly connected to the battery access device; the processing device is used to control the conveyor belt to drive the battery access device to move on the bracket. By applying the technical solution of the embodiment of the present application, a conveying mechanism including a bracket and a conveyor belt can be used to realize the automatic connection and automatic separation functions of the measuring battery and the external resistor. Thereby, a self-discharge system is realized that can automatically connect the batteries to be measured in parallel when a start command is detected, thereby reducing the parallel resistance of the circuit.

[0027] According to another aspect of the embodiments of the present application, a device for testing battery self-discharge is provided, comprising:

[0028] a calculation module configured to calculate an external resistance value and an external duration based on electrical parameters of the battery to be tested;

[0029] a processing module configured to perform a parallel operation of the external connection duration on the battery to be tested, wherein the parallel operation is used to connect the battery to be tested in parallel with an external resistor of the external resistance value;

[0030] The determination module is configured to determine a voltage drop of the battery to be tested obtained by the parallel operation, and calculate a self-discharge result of the battery to be tested based on the voltage drop.

[0031] By applying the technical solution of the embodiment of the present application, in the process of determining the voltage drop of the battery, it is possible to choose to connect it in parallel with an external resistor of a specific resistance for a certain period of time, and then complete the self-discharge test of the battery based on the voltage drop result after the parallel connection. Thereby achieving a method of accelerating the battery discharge process by reducing the parallel resistance of the circuit, thereby shortening the time it takes to obtain the battery voltage drop. Thereby alleviating the problem that occurs in the related art, when the capacity of the battery is large or the accuracy standard of the test instrument is low, the battery needs to be left to stand for a long time before a reliable voltage drop can be measured, resulting in a long self-discharge time of the test battery.

[0032] According to another aspect of the embodiments of the present application, an electronic device is provided, including:

[0033] a memory for storing executable instructions; and

[0034] A processor is configured to execute the executable instructions with the memory to complete the operations of any of the above methods.

[0035] According to another aspect of the embodiments of the present application, a computer-readable storage medium is provided for storing computer-readable instructions, which, when executed, perform the operations of any of the above-described methods.

[0036] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other effects, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present application and, together with the description, serve to explain the principles of the present application.

[0038] The present application can be more clearly understood from the following detailed description with reference to the accompanying drawings, in which:

[0039] FIG1 is a schematic diagram showing a method for testing battery self-discharge provided by an embodiment of the present application;

[0040] FIG2 is a schematic diagram showing the overall flow of a method for testing battery self-discharge provided by an embodiment of the present application;

[0041] FIG3 shows a schematic diagram of a system architecture for testing battery self-discharge provided by an embodiment of the present application;

[0042] FIG4 shows a schematic structural diagram of an electronic device provided in one embodiment of the present application;

[0043] FIG5 shows a schematic structural diagram of an electronic device provided in an embodiment of the present application;

[0044] FIG6 shows a schematic diagram of a storage medium provided in an embodiment of the present application. DETAILED DESCRIPTION

[0045] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0046] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for describing the effects of specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0047] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0048] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0049] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0050] The following describes a method for testing battery self-discharge according to an exemplary embodiment of the present application in conjunction with Figures 1-3. It should be noted that the following application scenarios are merely provided to facilitate understanding of the spirit and principles of the embodiments of the present application, and the embodiments of the present application are not limited in this respect. On the contrary, the embodiments of the present application can be applied to any applicable scenario.

[0051] The electronic device disclosed in the embodiments of the present application may be one or more computing devices, or may be a server or a server cluster composed of multiple servers.

[0052] In the related art, power batteries are core components of electric vehicles and other electric devices. For example, power batteries can be lithium batteries. As an efficient and convenient energy storage method, lithium batteries have penetrated into every corner of our lives.

[0053] In one way, mobile / non-mobile electronic devices, such as mobile phones, tablet computers, laptops, digital cameras, etc., cannot do without lithium batteries to provide these devices with portable and long-lasting power.

[0054] Furthermore, lithium batteries also play an important role in the field of electric vehicles. Nowadays, more and more electric vehicles use lithium batteries as a power source. Their high energy density and environmentally friendly properties enable electric vehicles to have a longer driving range and lower emissions.

[0055] In one approach, power battery tests include various types, such as external short circuit tests, thermal shock tests, extrusion tests, overcharge tests, and self-discharge tests.

[0056] Among them, the self-discharge test of the battery usually refers to the use of certain instruments and steps to measure the battery's voltage, current, capacity, internal resistance, temperature and other parameters during the discharge process to evaluate the battery's performance and life.

[0057] In one embodiment, there are multiple methods for performing self-discharge testing on a battery. In the embodiment of the present application, a suitable method can be selected according to factors such as the type, specification, application environment, and service life of different batteries to be tested.

[0058] As an example, the self-discharge test of the battery in the embodiment of the present application can be a discharge test of the battery under normal use scenarios, a discharge test of the battery under extreme scenarios, or a discharge test of the battery under destructive scenarios.

[0059] As an example, the self-discharge test of the embodiment of the present application under normal usage scenarios is: simulating the discharge process of the battery under normal usage conditions, such as using the battery in mobile phones, computers, electric vehicles and other devices, and recording the battery's discharge time, voltage changes, temperature changes and other data to evaluate the battery's self-discharge results.

[0060] As an example, the self-discharge test of the embodiment of the present application in extreme scenarios is: performing a discharge test on the battery under some extreme conditions, such as high temperature, low temperature, high voltage, high rate, over-discharge, etc., to evaluate the self-discharge results of the battery.

[0061] As another example, the self-discharge test of the application embodiment in a destructive scenario is: performing some destructive operations on the battery, such as needle puncture, fire, high-altitude drop, collision, etc., to observe the battery's reaction and degree of damage, thereby evaluating the battery's self-discharge results.

[0062] As another example, the self-discharge test of the application embodiment in the electrochemical scenario is: using some professional electrochemical instruments, such as battery testing systems, electrochemical workstations, etc., to perform some electrochemical tests on the battery, such as cyclic voltammetry, electrochemical impedance, charge and discharge, differential voltage / capacitance, rate, cycle, etc., to analyze the electrochemical reaction process and parameters of the battery, to evaluate the battery's capacity, internal resistance, power, cycle life, electrochemical stability, etc., to evaluate the battery's self-discharge results.

[0063] In the related art, there is a problem in the process of self-discharge testing of batteries in the prior art. That is, the identification of abnormal self-discharge cells in lithium-ion batteries mostly adopts the method of measuring voltage drop. However, when the battery capacity is large or the accuracy of the test instrument is limited, it often takes a long time to measure the voltage drop reliably, thereby obtaining the battery self-discharge result.

[0064] Therefore, to address the aforementioned issue in related art where determining the battery voltage drop takes a long time, leading to a long battery self-discharge test, the present invention provides a method for testing battery self-discharge. The method comprises: during the process of determining the battery voltage drop, the battery is connected in parallel with an external resistor of a specific resistance for a certain period of time, and then the battery self-discharge test is completed based on the voltage drop result after the parallel connection.

[0065] In one embodiment, the present application further provides a method, system, and device for testing battery self-discharge.

[0066] FIG1 schematically shows a flow chart of a method for testing battery self-discharge according to an embodiment of the present application. As shown in FIG1 , the method includes:

[0067] S101 , calculating an external connection resistance and an external connection duration based on electrical parameters of the battery to be tested.

[0068] S102 , performing a parallel operation for an external connection time on the battery to be tested, wherein the parallel operation is used to connect the battery to be tested in parallel with an external resistor of an external resistance value.

[0069] S103 , determining a voltage drop of the battery to be tested obtained by the parallel operation, and calculating a self-discharge result of the battery to be tested based on the voltage drop.

[0070] In the related art, when actually testing a battery, it is usually chosen to perform voltage drop identification on the battery to be tested, and then obtain the self-discharge result based on the voltage drop identification.

[0071] In one approach, embodiments of the present application can pre-select an external resistor with an appropriate resistance value and an appropriate external connection duration based on the current electrical parameters of the battery to be tested. This allows the two resistors to be subsequently connected in parallel for a certain period of time to accelerate the battery voltage drop. This can also reduce the accuracy limitations of the voltage test instrument, allowing for rapid identification of self-discharge.

[0072] In one embodiment, the electrical parameters of the battery to be tested may be the battery's self-discharge rate limit, battery capacity, battery resistance, and the like.

[0073] In one embodiment, the present application can calculate the self-discharge result of the battery to be tested by the following steps:

[0074] Step a: Obtain electrical parameters of the battery to be tested.

[0075] The electrical parameters may include the self-discharge rate limit value, battery capacity, battery resistance, etc. of the battery to be tested.

[0076] Step b: Let the battery to be tested stand for a period of time to eliminate the voltage polarization phenomenon generated during the most recent charge and discharge process.

[0077] As an example, the rest time of the battery to be tested may be determined by the cell system, battery material, and current size of the battery to be tested.

[0078] For example, when it is detected that the positive electrode material of the battery to be tested uses lithium iron phosphate material, the battery material of the test battery is determined to be "lithium iron phosphate material", and then the battery is left to stand for a longer period of time.

[0079] For another example, when it is detected that the positive electrode material of the battery to be tested uses a ternary lithium material, the battery material of the test battery is determined to be a "ternary lithium material", and then the battery is placed at rest for a relatively short period of time.

[0080] Step c: using a voltage measurement module to measure a first open circuit voltage value of the battery to be tested.

[0081] As an example, the first open circuit voltage value of the battery to be tested is its voltage value before the parallel operation is performed, which is recorded as OCV1.

[0082] Step d: Connect the battery to be tested in parallel with the external resistor having the external resistance value, and the duration of the connection is equal to the external connection duration.

[0083] Step e: After the external connection time has elapsed, the battery to be tested is separated from the external resistor, and a second open circuit voltage value of the battery to be tested is measured using a voltage measurement module.

[0084] Step f: obtaining a voltage drop of the battery to be tested based on the first open circuit voltage value and the second open circuit voltage value.

[0085] Step g: Calculate the self-discharge result of the battery to be tested based on the voltage drop and the external resistance.

[0086] As an example, the battery discharge rate calculation process of the battery to be tested is:

[0087] First, the difference between the first open circuit voltage value and the second open circuit voltage value is calculated, and based on the difference and the external resistance value of the external resistor, the self-discharge rate of the battery can be obtained.

[0088] In summary, the technical solution of the embodiments of the present application is to, during the process of determining the battery voltage drop, selectively connect it in parallel with an external resistor of a specific resistance value for a certain period of time, and then perform a self-discharge test on the battery based on the voltage drop result after the parallel connection. This achieves a method of accelerating the battery discharge process by reducing the parallel resistance of the circuit, thereby shortening the time it takes to obtain the battery voltage drop.

[0089] The above description of the various embodiments tends to emphasize the differences between the various embodiments. The same or similar aspects can be referenced with each other and will not be repeated herein for the sake of brevity.

[0090] By applying the technical solution of the embodiment of the present application, in the process of determining the voltage drop of the battery, it is possible to choose to connect it in parallel with an external resistor of a specific resistance for a certain period of time, and then complete the self-discharge test of the battery based on the voltage drop result after the parallel connection. Thereby achieving a method of accelerating the battery discharge process by reducing the parallel resistance of the circuit, thereby shortening the time it takes to obtain the battery voltage drop. Thereby alleviating the problem that occurs in the related art, when the capacity of the battery is large or the accuracy standard of the test instrument is low, the battery needs to be left to stand for a long time before a reliable voltage drop can be measured, resulting in a long self-discharge time of the test battery.

[0091] Optionally, in another embodiment of the above method of the present application, the external resistance is calculated based on the electrical parameters of the battery to be tested, including: determining the external resistance limit value based on the self-discharge rate limit value of the battery to be tested; and using a target resistance value that is less than the external resistance limit value as the external resistance value.

[0092] In one embodiment, the embodiment of the present application can calculate the external resistance limit value corresponding to the external resistor based on the self-discharge rate limit value pre-defined for the battery to be tested.

[0093] In one embodiment, the self-discharge rate limit of the battery under test is a preset value for the battery under test. For example, the self-discharge rate limit may be a monthly self-discharge rate limit of 2%. This means that the self-discharge frequency of the battery should not exceed 2% within a month.

[0094] In another embodiment, the external resistor limit value is the upper limit value of the resistance of the external resistor. It is understandable that when the resistance value of the external resistor is too high, the self-discharge rate requirement of the battery to be tested cannot be met.

[0095] It can be understood that after the external resistance limit value corresponding to the external resistor is determined, a resistance value smaller than the external resistance limit value (but greater than 0) can be used as the external resistance value of the external resistor.

[0096] As an example, when the external resistance limit value corresponding to the external resistor is 10 ohms, the external resistance value of the external resistor may be 3 ohms, 5 ohms, and so on.

[0097] By applying the technical solutions of the embodiments of the present application, the maximum resistance value of a resistor connected in parallel with the battery can be first determined based on the battery's self-discharge rate limit, so that an external resistor with a value smaller than the maximum resistance value can be subsequently connected in parallel with the resistor. This alleviates the disadvantage that when the external resistor's resistance value is too large, the external resistor inhibits the discharge of the battery under test due to a large voltage difference between the battery under test and the external resistor.

[0098] Optionally, in another embodiment of the above method of the present application, the external resistance limit value is determined based on the self-discharge rate limit value of the battery to be tested, including: calculating the self-discharge current limit value of the battery to be tested based on the self-discharge rate limit value of the battery to be tested and the battery capacity; and obtaining the first open-circuit voltage value of the battery to be tested; and calculating the external resistance limit value based on the self-discharge current limit value and the first open-circuit voltage value.

[0099] In one embodiment, the present invention may implement the following steps in the process of calculating the external resistance limit value of the external resistor:

[0100] As an example, for example, the monthly self-discharge rate limit value defined for the battery to be tested is k1 (calculated as 30 days per month), the battery cell capacity is Q, and the first open circuit voltage value is OCV1:

[0101] Then, the self-discharge current limit value of the battery to be tested is: I_max=k1*Q / 30 / 24.

[0102] As you can understand, 30 is the number of days in a month and 24 is the number of hours in a day.

[0103] As another example, the calculation process of the external resistance limit value R of the external resistor is: R=OCV1 / I_max.

[0104] As another example, the external resistance of the external resistor is recorded as R', where R'>0.

[0105] As an example, the external resistance R' of the external resistor may be greater than 1 / 3 R. It is understandable that when the external resistance is too small, the voltage drop signal of the external resistor will mask the voltage drop signal generated by the self-discharge of the battery under test.

[0106] By applying the technical solutions of the embodiments of the present application, the maximum resistance value of a resistor connected in parallel with the battery can be further determined based on the battery's self-discharge rate limit and the battery capacity, so that an external resistor with a smaller resistance than the maximum resistance value can be subsequently connected in parallel with the resistor. This alleviates the disadvantage that when the external resistor's resistance value is too large, the external resistor may inhibit the discharge of the battery under test due to a large voltage difference between the battery under test and the external resistor.

[0107] Optionally, based on the electrical parameters of the battery to be tested, the external connection time is calculated, including: calculating the parallel resistance value corresponding to the parallel operation based on the external resistance value and the internal resistance of the battery to be tested; calculating the ratio of the preset voltage change to the parallel resistance value, and using the ratio as the sample self-discharge current of the battery to be tested; the preset voltage change is the lowest voltage change that can be measured by the voltage measurement module; determining the sample charge change of the battery to be tested and the sample charge change of the battery to be tested when the sample voltage change reaches the preset voltage change; and calculating the external connection time based on the sample charge change and the sample self-discharge current.

[0108] As an example, the present embodiment assumes that the capacitance of the battery to be tested is 300Ah, the self-discharge rate limit is no more than 3%, and the minimum voltage change ΔV ≥ 10mV (i.e., the voltage measurement module requires that the measured data be considered reliable only when ΔV ≥ 10mV). The first open-circuit voltage value is OCV1, the internal resistance of the battery to be tested is R_leak, and the external resistance value of the external resistor is R'.

[0109] First, the embodiment of the present application needs to calculate the parallel resistance value R1 corresponding to the parallel operation: R1 = 1 / 2*(R_leak+R')

[0110] Wherein, R' is the external resistance value of the external resistor, and R_leak is the internal resistance of the battery to be tested.

[0111] Secondly, the embodiment of the present application first needs to calculate the sample self-discharge current I_leak of the battery to be tested: I_leak=ΔV / R1.

[0112] Among them, △V is the minimum voltage change, and R1 is the parallel resistance value.

[0113] Thirdly, the embodiment of the present application needs to calculate the sample charge change ΔQ of the battery to be tested: ΔQ=1*ΔV.

[0114] As an example, an embodiment of the present application can obtain a preset numerical correlation between the charge change and voltage change of the battery to be tested; based on the sample voltage change, the sample charge change of the battery to be tested is queried from the numerical correlation.

[0115] Fourthly, according to the above calculation results, the embodiment of the present application can calculate the external connection time t of the external resistor: t=ΔQ / I_leak.

[0116] By applying the technical solutions of the embodiments of the present application, the degree of change in the capacity of the battery under test that can be achieved during parallel operation can be calculated based on the parallel resistance value and the minimum voltage change of the parallel system. Based on this degree of change, the most appropriate external connection time for parallel connection can be determined, so that the battery under test can be subsequently operated in parallel based on this external connection time. This alleviates the problem that when the external connection time of the parallel connection is too long, the waiting time for obtaining the battery voltage drop will be unnecessarily increased, thereby increasing the self-discharge test time.

[0117] Optionally, in another embodiment based on the above method of the present application, determining the charge change of the battery to be tested when the voltage changes by a preset voltage change includes: obtaining a preset numerical correlation relationship for reflecting the charge change and voltage change of the battery to be tested; and based on the sample voltage change, querying and obtaining the sample charge change of the battery to be tested from the numerical correlation relationship.

[0118] By applying the technical solutions of the embodiments of the present application, in the process of determining the most appropriate external connection time for parallel connection of the batteries to be tested, the degree of change in voltage capacity can be determined based on the degree of change in the charge capacity that the batteries can achieve during parallel operation, based on a preset numerical correlation. This allows the most appropriate external connection time for parallel connection of the batteries to be tested to be subsequently determined based on the degree of change in voltage capacity. This alleviates the problem of an excessively long external connection time for parallel connection, which unnecessarily increases the waiting time for obtaining the battery voltage drop and thus increases the self-discharge test time.

[0119] Optionally, in another embodiment based on the above method of the present application, the parallel operation for an external connection time period is performed on the battery to be tested, including: obtaining a test instruction for self-discharging the battery to be tested, and determining a preset temperature and humidity environment based on the battery material and current electrical performance indicators of the battery to be tested; under the preset temperature and humidity environment, performing a parallel operation for an external connection time period on the battery to be tested.

[0120] In one embodiment, the present application can select a temperature and humidity environment that can best accelerate the self-discharge rate of batteries to be tested in different electrical performance states.

[0121] For example, for a battery made of lithium iron phosphate material, the basic electrical performance range is range A, and its fastest discharge temperature environment is 78°C-82°C. Therefore, the embodiment of the present application can select this temperature environment to perform parallel operation of the battery to be tested for a long external connection time.

[0122] For another example, for a battery made of "ternary lithium material", the basic electrical performance range is range B, and its fastest discharge temperature environment is 60°C-62°C. Therefore, the embodiment of the present application can select this temperature environment to perform parallel operation of the battery to be tested for a long external connection time.

[0123] By applying the technical solutions of the embodiments of the present application, before connecting batteries in parallel, a temperature and humidity environment that best achieves rapid discharge can be selected based on the battery's electrical performance indicators. The batteries to be tested can then be connected in parallel for a prolonged period of time in this temperature and humidity environment. This further accelerates the battery discharge process and shortens the time it takes to obtain the battery voltage drop.

[0124] Optionally, in another embodiment based on the above method of the present application, determining the voltage drop of the battery to be tested obtained by parallel operation includes: obtaining a first open-circuit voltage value of the battery to be tested before the parallel operation is performed; and obtaining a second open-circuit voltage value of the battery to be tested after the parallel operation is performed; and obtaining the voltage drop of the battery to be tested based on the first open-circuit voltage value and the second open-circuit voltage value.

[0125] In one embodiment, the calculation process of the voltage drop of the battery to be tested in the embodiment of the present application is: ΔOCV=(OCV1-OCV2).

[0126] Wherein, OCV1 is a first open circuit voltage value, and OCV2 is a second open circuit voltage value.

[0127] By applying the technical solution of the embodiment of the present application, in the process of determining the voltage drop of the battery, the voltage drop result can be calculated based on the two open-circuit voltage values ​​of the battery before and after being connected in parallel, so that the self-discharge test of the battery can be completed based on the voltage drop result. Thereby, a method of accelerating the battery discharge process by reducing the parallel resistance of the circuit is achieved, thereby shortening the time it takes to obtain the battery voltage drop. Thereby alleviating the problem that occurs in the related art, when the battery capacity is large or the accuracy standard of the test instrument is low, the battery needs to be left to stand for a long time before a reliable voltage drop can be measured, resulting in a long self-discharge time of the test battery.

[0128] Optionally, calculating the self-discharge result of the battery to be tested based on the voltage drop includes: calculating the self-discharge result of the battery to be tested based on the voltage drop and an external resistance.

[0129] In one embodiment, the calculation process of the discharge rate of the battery to be tested in the embodiment of the present application is: I = (OCV1-OCV2) / R1;

[0130] Wherein, R1 is the parallel resistance value corresponding to the battery to be tested and the external resistor after being connected in parallel.

[0131] In another embodiment, the calculation process of the self-discharge rate of the battery to be tested in the embodiment of the present application is: I_leak=I-(OCV1-OCV2) / R';

[0132] Wherein, R' is the external resistance value of the external resistor.

[0133] As an example, a method for testing battery self-discharge proposed in an embodiment of the present application is specifically described with reference to FIG2 :

[0134] Step 1a: Determine the external resistance limit value based on the self-discharge rate limit value of the battery to be tested.

[0135] It should be noted that step 1a and step 1b in the embodiment of the present application can be executed simultaneously or in any order.

[0136] In one embodiment, in the process of determining the external resistance limit value, the embodiment of the present application can calculate the self-discharge current limit value of the battery to be tested based on the self-discharge rate limit value of the battery to be tested and the battery capacity; and obtain the first open-circuit voltage value of the battery to be tested, so that the external resistance limit value can be subsequently calculated based on the self-discharge current limit value and the first open-circuit voltage value.

[0137] Step 2a: Set the target resistance value, which is less than the external resistance limit value, as the external resistance value. Then proceed to step 4.

[0138] As an example, the target resistance value may be one third of the external resistance limit value.

[0139] Step 1b: Calculate the parallel resistance value corresponding to the parallel operation based on the external resistance value and the internal resistance of the battery to be tested.

[0140] In one embodiment, the parallel resistance value is the resistance value of a circuit formed by connecting the external resistor and the battery to be tested in parallel.

[0141] Step 2b: Calculate the ratio of the preset voltage change to the parallel resistance value, and use the ratio as the sample self-discharge current of the battery to be tested; the preset voltage change is the minimum voltage change that can be measured by the voltage measurement module.

[0142] Step 3b: Determine the sample charge change of the battery to be tested when the voltage changes by a preset voltage change, and calculate the external connection time based on the sample charge change and the sample self-discharge current. Then proceed to step 4.

[0143] Step 4: Determine the preset temperature and humidity environment based on the battery material and current electrical performance indicators of the battery to be tested.

[0144] Step 5: Under the preset temperature and humidity environment, perform parallel operation on the batteries to be tested for a certain period of time.

[0145] The parallel operation is used to connect the battery to be tested in parallel with an external resistor with an external resistance value.

[0146] Step 6: Obtain a first open circuit voltage value of the batteries to be tested before the parallel operation is performed; and obtain a second open circuit voltage value of the batteries to be tested after the parallel operation is performed.

[0147] Step 7: Obtain the voltage drop of the battery to be tested based on the first open circuit voltage value and the second open circuit voltage value.

[0148] Step 8: Based on the voltage drop and the external resistance, calculate the self-discharge result of the battery to be tested.

[0149] By applying the technical solutions of the embodiments of the present application, during the process of determining the battery voltage drop, a voltage drop result can be calculated based on the two open-circuit voltage values ​​of the batteries before and after they are connected in parallel, so that the battery self-discharge test can be completed based on this voltage drop result and the resistance value of the external resistor. This achieves the effect of accelerating the battery discharge process by reducing the parallel resistance of the circuit, thereby shortening the battery voltage drop acquisition time.

[0150] In one embodiment, the present application further provides a method, system, and device for testing battery self-discharge.

[0151] Figure 3 schematically illustrates a schematic diagram of the architecture of a system for testing battery self-discharge according to an embodiment of the present application. As shown in Figure 3, the system includes a voltage measurement module, a parallel resistance module, a battery access device, and a processing device, wherein:

[0152] The voltage measurement module is connected to the processing device;

[0153] The battery access device is used to connect to the battery to be tested, and is used to connect to the voltage measurement module to form a voltage measurement loop in a first state, and to connect to the parallel resistance module to form a self-discharge loop in a second state.

[0154] In one embodiment, the voltage measurement module in the system for testing battery self-discharge in the embodiment of the present application can be used to measure two open-circuit voltage values ​​(i.e., the first open-circuit voltage value and the second open-circuit voltage value) of the battery to be tested before and after being connected in parallel, and use this to calculate the voltage drop result, so that the self-discharge test of the battery can be completed subsequently based on the voltage drop result.

[0155] In another embodiment, the parallel resistor module in the embodiment of the present application can be used to perform a parallel operation with the battery to be tested for a certain external connection time.

[0156] As an example, the embodiment of the present application does not limit the number of parallel resistance modules, for example, it can be one or more.

[0157] As another example, the parallel resistor module in the embodiment of the present application may include one or more external resistors with fixed resistance values, or one or more external resistors with variable resistance values.

[0158] In another embodiment, the battery access device in the embodiment of the present application can be used to perform a connection operation with a battery to be tested.

[0159] In one embodiment, the processing device in the embodiment of the present application can be used to store two open circuit voltage values ​​(i.e., a first open circuit voltage value and a second open circuit voltage value) of the batteries to be tested before and after being connected in parallel. And, subsequently, the voltage drop result and the self-discharge result are calculated based on the first open circuit voltage value and the second open circuit voltage value.

[0160] By applying the technical solution of the embodiment of the present application, a system for automatically connecting the batteries to be tested in parallel can be realized by using a voltage measurement module, a parallel resistance module, a battery access device, and a processing device. This can further achieve an effect of accelerating the battery discharge process by reducing the parallel resistance of the circuit, thereby shortening the battery voltage drop acquisition time. This can alleviate the problem of a long self-discharge time of the test battery caused by the need to let the battery rest for a long time before a reliable voltage drop can be measured in the related art when the battery capacity is large or the accuracy standard of the test instrument is low.

[0161] In one optional embodiment, the parallel resistor module includes at least one parallel branch; the parallel branch includes a first external port, a second external port and at least one resistor, one end of the circuit formed by the at least one resistor is connected to the first external port, and the other end of the circuit is connected to the second external port; the first external port of each parallel branch is independent of each other, and the second external port of each parallel branch is independent of each other; the first external port and the second external port are respectively used to connect to the positive terminal and the negative terminal of the battery access device.

[0162] In one embodiment, the number of parallel branches in the embodiment of the present application can be one or more.

[0163] For example, in the case of multiple parallel branches, the resistance values ​​of the resistors in each branch may be the same or different. For example, if the resistance values ​​of the branches are different, the processor may select a resistor from the multiple branches that is less than the calculated resistance limit of the external resistor as the external resistor, so that the battery to be tested can be connected to the selected branch by subsequently controlling the transmission mechanism.

[0164] As another example, in the case of a parallel branch, the resistance of the branch can have a variable resistance characteristic. That is, the processor can, based on the calculated resistance limit of the external resistor, change the resistance of the branch to a resistance that is less than the resistance limit, and use this resistance as the external resistor to subsequently connect the battery under test to the selected branch.

[0165] In one embodiment, each parallel branch is connected to the battery access device through its two external connection ports (ie, the first external connection port and the second external connection port).

[0166] In one embodiment, the positive terminal and the negative terminal of the battery access device of the embodiment of the present application are connected to the first port and the second port to realize the connection between the parallel resistor module and the battery access device.

[0167] By applying the technical solutions of the embodiments of the present application, a parallel branch circuit comprising multiple external ports can be used to automatically open and close the parallel connection of the batteries to be tested. Furthermore, an external resistor can be connected to the positive and negative terminals of the battery by controlling the multiple external ports to reduce the parallel resistance of the circuit.

[0168] Optionally, the voltage measurement module includes a code scanning element, a measuring element, a first port and a second port; the code scanning element and the measuring element are connected in parallel between the first port and the second port, and the first port and the second port are respectively used to connect the positive terminal and the negative terminal of the battery access device; the code scanning element and the measuring element are both connected to the processing device.

[0169] In one embodiment, the measuring element in the embodiment of the present application may be a voltmeter, and the code scanning element may be used to scan the battery serial number of the battery to be tested.

[0170] It can be understood that the code scanning element and the measuring element in the embodiment of the present application can be connected to the battery access device through the first port and the second port.

[0171] By applying the technical solution of the embodiment of the present application, a voltage measurement module including a code scanning element, a measuring element, a first port and a second port can be used to measure the open circuit voltage value of the battery before and after parallel connection, and the voltage value can be associated with the battery identification obtained by scanning using the code scanning element, so as to subsequently obtain the voltage drop result of the battery.

[0172] Optionally, the battery access device includes a first switch, a second switch, a positive connection terminal, and a negative connection terminal; the positive connection terminal and the negative connection terminal are respectively used to connect the positive electrode and negative electrode of the battery to be tested; one end of the first switch is connected to the positive connection terminal, and the other end of the first switch is used to switch the connection between the positive end of the voltage measurement module or the positive end of the parallel resistance module; one end of the second switch is connected to the negative connection terminal, and the other end of the second switch is used to switch the connection between the negative end of the voltage measurement module or the negative end of the parallel resistance module.

[0173] In one embodiment, the positive terminal and the negative terminal of the voltage measurement module of the embodiment of the present application are connected to the first port and the second port to achieve the connection between the voltage measurement module and the battery access device.

[0174] By applying the technical solutions of the embodiments of the present application, a battery access device including a first switch, a second switch, a positive connection terminal, and a negative connection terminal can be used to measure the open-circuit voltage value of the battery before and after parallel connection, thereby realizing a method of connecting an external resistor to the positive and negative terminals of the battery in a manner that multiple external ports are mutually controlled to achieve the effect of reducing the parallel resistance of the circuit.

[0175] Optionally, the system also includes a conveying mechanism; the battery access device is arranged on the conveying mechanism, and the conveying mechanism is connected to the processing device; the processing device is used to control the conveying mechanism to drive the battery access device to move toward the voltage measurement module in the first state, and to control the conveying mechanism to drive the battery access device to move toward the parallel resistance module in the second state.

[0176] By applying the technical solutions of the embodiments of the present application, a transmission mechanism can be used to connect and disconnect the measuring battery and the external resistor, thereby realizing a self-discharge system that can automatically connect the measured battery in parallel upon detecting a start command, thereby reducing the parallel resistance of the circuit.

[0177] Optionally, the conveying mechanism includes a bracket and a conveyor belt; the bracket is arranged between the voltage measurement module and the parallel resistance module; the battery access device is slidingly connected to the bracket, and the conveyor belt is fixedly connected to the battery access device; the processing device is used to control the conveyor belt to drive the battery access device to move on the bracket.

[0178] By applying the technical solutions of the embodiments of the present application, a conveyor mechanism comprising a bracket and a conveyor belt can be used to automatically connect and disconnect the test battery from the external resistor. This provides a self-discharge system that automatically connects the test battery in parallel upon detecting a start command, thereby reducing the parallel resistance of the circuit.

[0179] As an example, the steps of executing a system for testing battery self-discharge proposed in an embodiment of the present application are specifically described:

[0180] Step a: The battery to be tested is connected to the test system, the first switch is connected to the first port, the second switch is connected to the second port, the barcode scanning component scans the battery, records the battery number, and inputs it into the processor;

[0181] Step b: Use a voltmeter to measure the first open circuit voltage value OCV1 of the battery to be tested, input the value into the processor, match it with the cell number, and turn off the first switch and the second switch;

[0182] Step c: Connect the first switch to the first external port, connect the second switch to the second external port, and connect the resistor R' in parallel to the positive and negative electrodes of the battery to be tested;

[0183] Step d: After the batteries are connected in parallel, they are stored in a warehouse. After the external connection time t, the first switch and the second switch are disconnected.

[0184] Step e: The first switch is connected to the first port, the second switch is connected to the second port, and the scanning component scans the battery, records the battery serial number, and inputs it into the processor;

[0185] Step f: Use a voltmeter to measure the second open circuit voltage (OCV2) of the battery to be tested, input the value into the processor, match it with the cell number, and turn off the first switch and the second switch;

[0186] Step g: The processor calculates and outputs the battery self-discharge current value based on the measured four parameters OCV1, OCV2, t, and R';

[0187] Step h: The processor compares the measured self-discharge current value with a preset self-discharge threshold value, and controls the batteries to be tested that meet the quality requirements to flow into the next process, otherwise they flow into the defective product bin.

[0188] By applying the technical solution of the embodiment of the present application, in the process of determining the voltage drop of the battery, it is possible to choose to connect it in parallel with an external resistor of a specific resistance for a certain period of time, and then complete the self-discharge test of the battery based on the voltage drop result after the parallel connection. Thereby achieving a method of accelerating the battery discharge process by reducing the parallel resistance of the circuit, thereby shortening the time it takes to obtain the battery voltage drop. Thereby alleviating the problem that occurs in the related art, when the capacity of the battery is large or the accuracy standard of the test instrument is low, the battery needs to be left to stand for a long time before a reliable voltage drop can be measured, resulting in a long self-discharge time of the test battery.

[0189] The above description of the various embodiments tends to emphasize the differences between the various embodiments. The same or similar aspects can be referenced with each other and will not be repeated herein for the sake of brevity.

[0190] Optionally, in another embodiment of the present application, as shown in FIG4 , the present application further provides a device for testing battery self-discharge, which includes:

[0191] The calculation module 201 is configured to calculate the external resistance value and the external connection time based on the electrical parameters of the battery to be tested;

[0192] The processing module 202 is configured to perform a parallel operation of the external connection duration on the battery to be tested, wherein the parallel operation is used to connect the battery to be tested in parallel with an external resistor of the external resistance value;

[0193] The determination module 203 is configured to determine a voltage drop of the battery to be tested obtained by the parallel operation, and calculate a self-discharge result of the battery to be tested based on the voltage drop.

[0194] By applying the technical solution of the embodiment of the present application, in the process of determining the voltage drop of the battery, it is possible to choose to connect it in parallel with an external resistor of a specific resistance for a certain period of time, and then complete the self-discharge test of the battery based on the voltage drop result after the parallel connection. Thereby achieving a method of accelerating the battery discharge process by reducing the parallel resistance of the circuit, thereby shortening the time it takes to obtain the battery voltage drop. Thereby alleviating the problem that occurs in the related art, when the capacity of the battery is large or the accuracy standard of the test instrument is low, the battery needs to be left to stand for a long time before a reliable voltage drop can be measured, resulting in a long self-discharge time of the test battery.

[0195] In another embodiment of the present application, the processing module 202 is configured to:

[0196] Determining an external resistance limit value based on a self-discharge rate limit value of the battery to be tested;

[0197] A target resistance value that is smaller than the external resistance limit value is used as the external resistance value.

[0198] In another embodiment of the present application, the processing module 202 is configured to:

[0199] Calculating a self-discharge current limit value of the battery to be tested based on the self-discharge rate limit value and the battery capacity of the battery to be tested; and obtaining a first open circuit voltage value of the battery to be tested;

[0200] The external resistance limit value is calculated based on the self-discharge current limit value and the first open circuit voltage value.

[0201] In another embodiment of the present application, the processing module 202 is configured to:

[0202] Calculating a parallel resistance value corresponding to the parallel operation based on the external resistance value and the internal resistance of the battery to be tested;

[0203] Calculating a ratio of a preset voltage change to the parallel resistance value, and using the ratio as a sample self-discharge current of the battery to be tested; the preset voltage change is a minimum voltage change that can be measured by the voltage measurement module;

[0204] determining a sample charge change of the battery to be tested when the sample voltage change reaches the preset voltage change;

[0205] The external connection time is calculated based on the sample power change and the sample self-discharge current.

[0206] In another embodiment of the present application, the processing module 202 is configured to:

[0207] Obtaining a preset numerical correlation relationship for reflecting a change in charge and a change in voltage of the battery to be tested;

[0208] Based on the sample voltage variation, the sample power variation of the battery to be tested is obtained by querying from the numerical association relationship.

[0209] In another embodiment of the present application, the processing module 202 is configured to:

[0210] Obtaining a test instruction for performing self-discharge processing on the battery to be tested, and determining a preset temperature and humidity environment based on the battery material and current electrical performance indicators of the battery to be tested;

[0211] Under the preset temperature and humidity environment, the batteries to be tested are subjected to a parallel operation for the external connection time.

[0212] In another embodiment of the present application, the processing module 202 is configured to:

[0213] Obtaining a first open circuit voltage value of the battery to be tested before the parallel operation is performed; and obtaining a second open circuit voltage value of the battery to be tested after the parallel operation is performed;

[0214] A voltage drop of the battery to be tested is obtained based on the first open circuit voltage value and the second open circuit voltage value.

[0215] In another embodiment of the present application, the processing module 202 is configured to:

[0216] A self-discharge result of the battery to be tested is calculated based on the voltage drop and the external resistance.

[0217] The above description of the various embodiments tends to emphasize the differences between the various embodiments. The same or similar aspects can be referenced with each other and will not be repeated herein for the sake of brevity.

[0218] The present application also provides an electronic device for performing the above-mentioned method for testing battery self-discharge. Please refer to Figure 5, which shows a schematic diagram of an electronic device provided by some embodiments of the present application. As shown in Figure 5, the electronic device 3 includes: a processor 300, a memory 301, a bus 302 and a communication interface 303, wherein the processor 300, the communication interface 303 and the memory 301 are connected via the bus 302; the memory 301 stores a computer program that can be run on the processor 300, and when the processor 300 runs the computer program, it executes the method for testing battery self-discharge provided by any of the aforementioned embodiments of the present application.

[0219] The memory 301 may include high-speed random access memory (RAM) and may also include non-volatile memory, such as at least one disk storage. The communication connection between the device network element and at least one other network element is achieved through at least one communication interface 303 (which may be wired or wireless), and may use the Internet, a wide area network, a local area network, a metropolitan area network, etc.

[0220] Bus 302 may be an ISA bus, a PCI bus, or an EISA bus. The bus may be divided into an address bus, a data bus, a control bus, and the like. Memory 301 is used to store programs, and processor 300 executes the programs upon receiving execution instructions. The method for testing battery self-discharge disclosed in any of the aforementioned embodiments of the present application may be applied to or implemented by processor 300.

[0221] The processor 300 may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above method can be completed by an integrated logic circuit of hardware in the processor 300 or instructions in the form of software. The above-mentioned processor 300 can be a general-purpose processor, including a processor (Central Processing Unit, referred to as CPU), a network processor (Network Processor, referred to as NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), an off-the-shelf programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. The various methods, steps and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed.

[0222] The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in the embodiments of the present application can be directly implemented and executed by a hardware decoding processor, or by a combination of hardware and software modules in the decoding processor. The software module can be located in a storage medium well-known in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, etc. The storage medium is located in memory 301, and processor 300 reads the information in memory 301 and, in conjunction with its hardware, completes the steps of the above method.

[0223] The electronic device provided in the embodiment of the present application and the method for testing battery self-discharge provided in the embodiment of the present application are based on the same inventive concept and have the same beneficial effects as the methods adopted, operated or implemented therein.

[0224] The above description of the various embodiments tends to emphasize the differences between the various embodiments. The same or similar aspects can be referenced with each other and will not be repeated herein for the sake of brevity.

[0225] An embodiment of the present application also provides a computer-readable storage medium corresponding to the method for testing battery self-discharge provided in the aforementioned embodiment. Please refer to Figure 6, which shows that the computer-readable storage medium is a program product 40, on which a computer program (i.e., program product) is stored. When the computer program is run by the processor, it will execute the method for testing battery self-discharge provided in any of the aforementioned embodiments.

[0226] It should be noted that examples of the computer-readable storage medium may also include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other optical or magnetic storage media, which are not listed here one by one.

[0227] The computer-readable storage medium provided in the above-mentioned embodiment of the present application and the method for testing battery self-discharge provided in the embodiment of the present application are based on the same inventive concept and have the same beneficial effects as the method adopted, run or implemented by the application program stored therein.

[0228] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A method for testing battery self-discharge, wherein: include: Based on the electrical parameters of the battery to be tested, calculate the external resistance value and external duration; Performing a parallel operation of the external connection time length on the battery to be tested, wherein the parallel operation is used to connect the battery to be tested in parallel with an external resistor of the external resistance value; A voltage drop of the battery to be tested obtained by the parallel operation is determined, and a self-discharge result of the battery to be tested is calculated based on the voltage drop.

2. The method of claim 1, wherein: The step of calculating the external resistance value based on the electrical parameters of the battery to be tested includes: Determining an external resistance limit value based on a self-discharge rate limit value of the battery to be tested; A target resistance value that is smaller than the external resistance limit value is used as the external resistance value.

3. The method of claim 2, wherein: The step of determining the external resistance limit value based on the self-discharge rate limit value of the battery to be tested includes: Based on the self-discharge rate limit value of the battery to be tested and the battery capacity, a self-discharge current limit value of the battery to be tested is calculated; and a first open circuit voltage value of the battery to be tested is obtained; The external resistance limit value is calculated based on the self-discharge current limit value and the first open circuit voltage value.

4. The method of claim 1, wherein: The method further comprises: Calculating a parallel resistance value corresponding to the parallel operation based on the external resistance value and the internal resistance of the battery to be tested; Calculate the ratio of the preset voltage change to the parallel resistance value, and use the ratio as the sample self-discharge current of the battery to be tested; the preset voltage change is the value that the voltage measurement module can measure. Minimum voltage change; Determine the sample power change of the battery to be tested when the sample voltage change reaches the preset voltage change; The external connection time length is calculated based on the sample power change and the sample self-discharge current.

5. The method of claim 4, wherein: The determining, when the sample voltage variation reaches the preset voltage variation, the sample power variation of the battery to be tested comprises: Obtaining a preset numerical correlation relationship between a change in charge and a change in voltage of the battery to be tested; Based on the sample voltage variation, the sample power variation of the battery to be tested is obtained by querying from the numerical association relationship.

6. The method according to any one of claims 1 to 3, wherein: The performing the parallel operation of the battery to be tested for the external connection time period includes: Obtaining a test instruction for performing self-discharge processing on the battery to be tested, and determining a preset temperature and humidity environment based on the battery material and current electrical performance indicators of the battery to be tested; Under the preset temperature and humidity environment, the batteries to be tested are subjected to a parallel operation for the external connection time.

7. The method according to any one of claims 1 to 3, wherein: The determining the voltage drop of the battery to be tested obtained by the parallel operation includes: Acquiring a first open circuit voltage value of the battery to be tested before the parallel operation is performed; and acquiring a second open circuit voltage value of the battery to be tested after the parallel operation is performed; A voltage drop of the battery to be tested is obtained based on the first open circuit voltage value and the second open circuit voltage value.

8. The method according to any one of claims 1 to 3, wherein: The step of calculating the self-discharge result of the battery to be tested based on the voltage drop includes: Based on the voltage drop and the external resistance, a self-discharge result of the battery to be tested is calculated.

9. A system for testing battery self-discharge, wherein: A method for testing battery self-discharge according to any one of claims 1 to 8, wherein the system comprises a voltage measurement module, a parallel resistance module, a battery access device, and a processing device; The voltage measurement module is connected to the processing device; The battery access device is used to connect the battery to be tested, and is used to connect with the voltage measurement module to form a voltage measurement loop in a first state, and to connect with the parallel resistance module to form a self-discharge loop in a second state.

10. The system of claim 9, wherein: The parallel resistance module includes at least one parallel branch; The parallel branch includes a first external port, a second external port and at least one resistor, one end of a circuit formed by the at least one resistor is connected to the first external port, and the other end of the circuit is connected to the second external port; The first external ports of the parallel branches are independent of each other, and the second external ports of the parallel branches are independent of each other; The first external connection port and the second external connection port are respectively used to connect to the positive terminal and the negative terminal of the battery access device.

11. The system according to claim 9 or 10, wherein: The voltage measurement module includes a code scanning element, a measuring element, a first port and a second port; The code scanning element and the measuring element are connected in parallel between the first port and the second port, and the first port and the second port are used to connect the positive terminal and the negative terminal of the battery access device respectively; The code scanning component and the measuring component are both connected to the processing device.

12. The system according to any one of claims 9 to 11, wherein: The battery access device includes a first switch, a second switch, a positive electrode connection terminal and a negative electrode connection terminal; The positive electrode connection terminal and the negative electrode connection terminal are used to connect the positive electrode and the negative electrode of the battery to be tested respectively; One end of the first switch is connected to the positive electrode connection terminal, and the other end of the first switch is used to switch the connection between the positive terminal of the voltage measurement module or the positive terminal of the parallel resistance module; One end of the second switch is connected to the negative electrode connection terminal, and the other end of the second switch is used to switch the connection between the negative terminal of the voltage measurement module or the negative terminal of the parallel resistance module.

13. The system according to any one of claims 9 to 12, wherein: The system also includes a conveying mechanism; The battery access device is arranged on the conveying mechanism, and the conveying mechanism is connected to the processing device; The processing device is used to control the transmission mechanism to drive the battery access device to move toward the voltage measurement module in the first state, and to control the transmission mechanism to drive the battery access device to move toward the parallel resistance module in the second state.

14. The system according to any one of claims 9 to 13, wherein: The conveying mechanism comprises a support and a conveyor belt; The bracket is arranged between the voltage measurement module and the parallel resistance module; The battery access device is slidably connected to the bracket, and the conveyor belt is fixedly connected to the battery access device; The processing device is used to control the conveyor belt to drive the battery access device to move on the bracket.

15. A device for testing battery self-discharge, wherein: include: A calculation module is configured to calculate an external resistance value and an external duration based on electrical parameters of the battery to be tested; a processing module configured to perform a parallel operation of the external connection time length on the battery to be tested, wherein the parallel operation is used to connect the battery to be tested in parallel with an external resistor of the external resistance value; The determination module is configured to determine a voltage drop of the battery to be tested obtained by the parallel operation, and calculate a self-discharge result of the battery to be tested based on the voltage drop.

16. An electronic device, wherein: include: A memory for storing executable instructions; as well as, A processor is used to execute the executable instructions to complete the operation of any method described in claims 1-8.

17. A computer-readable storage medium for storing computer-readable instructions, wherein: The instructions are used to execute the operations of the method described in any one of claims 1-8.

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