A method and system for detecting the energy storage performance of a battery pack

Abstract

The application relates to a storage battery pack energy storage performance detection method and system; the detection method comprises an energy storage performance detection step; the energy storage performance detection step comprises the following steps: obtaining an initial voltage value of a storage battery pack and obtaining a rated full-load voltage of the storage battery pack based on the initial voltage value; obtaining a preset number of voltage values of the storage battery pack after the storage battery pack is discharged for a first time length; setting the voltage value with the lowest value as a to-be-detected voltage value; obtaining a voltage difference value of the initial voltage value and the to-be-detected voltage value; obtaining a judgment pressure difference value based on the rated full-load voltage; judging whether the voltage difference value is greater than the judgment pressure difference value; if yes, obtaining a relative difference value of the voltage difference value and the judgment pressure difference value; and judging whether the relative difference value is greater than a first deviation value; if yes, sending a first prompt information to an intelligent terminal bound with the storage battery pack. The application has the effect of conveniently and timely understanding the condition of the storage battery pack.

Description

Technical Field

[0001] This application relates to the technical field of charging equipment, and in particular to a method and system for testing the energy storage performance of a battery pack. Background Technology

[0002] Electric bicycles are a type of transportation powered by battery packs. In recent years, they have become very popular in my country. Because electric bicycles are powered by battery packs, the battery packs need to be charged after a period of use.

[0003] To facilitate the charging of electric bicycles, charging stations have become widely available. Similar to gas pumps at gas stations, charging stations can be fixed to the ground or walls and are installed in public buildings, residential parking lots, or charging stations. Each charging station is equipped with a plug for connecting to an electric bicycle's socket.

[0004] Regarding the aforementioned technologies, the inventors discovered that when the performance of the battery pack in an electric vehicle decreases, it can easily lead to poor charging performance of the battery pack. Summary of the Invention

[0005] To facilitate timely understanding of the status of battery packs, this application provides a method and system for testing the energy storage performance of battery packs.

[0006] Firstly, the energy storage performance testing method for a battery pack provided in this application adopts the following technical solution.

[0007] A method for testing the energy storage performance of a battery pack includes an energy storage performance testing step; the energy storage performance testing step includes:

[0008] Obtain the initial voltage value of the battery pack and calculate the rated full-load voltage of the battery pack based on the initial voltage value;

[0009] After the battery pack has been discharged for a first period of time, the voltage values ​​of a preset number of batteries in the battery pack are obtained.

[0010] Set the lowest voltage value as the voltage to be detected;

[0011] The voltage difference between the initial voltage value and the voltage value to be detected is obtained.

[0012] The differential voltage value is determined based on the rated full-load voltage.

[0013] Determine whether the voltage difference is greater than the determined voltage difference value; if so, obtain the relative difference between the voltage difference and the determined voltage difference value; and,

[0014] Determine whether the relative difference is greater than the first deviation value; if it is, send a first prompt message to the smart terminal bound to the battery pack.

[0015] By adopting the above technical solution, after the connector is connected to the battery pack socket, the initial voltage value of the battery pack is collected. Based on the initial voltage value, the cloud determines the rated full-load voltage of the battery pack. The rated full-load voltage can determine the number of batteries in the battery pack, and thus the cloud can determine the voltage drop of the battery pack supplying power normally within the first time period, which is recorded as the judgment voltage difference value. The cloud compares the actual voltage drop of the battery pack with the judgment voltage difference value. When the actual voltage drop of the battery pack is greater than the judgment voltage difference value, and the relative difference between the two is greater than a first deviation value, it indicates that the energy storage performance of the battery pack has decreased. At this time, the cloud sends a first prompt message to the smart terminal bound to the battery pack, thereby reminding the user and allowing the user to understand the status of the battery pack in a timely manner.

[0016] Optionally, the smart terminal bound to the battery pack is bound by the user through scanning a code on the smart terminal.

[0017] By adopting the above technical solution, users can scan the QR code through their smart terminals to bind their identity, thereby binding the user's identity with the battery pack. Regardless of which charging station the user uses, the cloud can obtain the user's historical data and save and push all data during the usage process to the user's smart terminal.

[0018] Optionally, the detection method further includes a charging temperature monitoring step, which includes:

[0019] With the plug connected to the socket of the electric vehicle and the battery pack charging, the initial temperature of the plug is obtained, and a temperature warning value is obtained based on the initial temperature.

[0020] After a second time interval, obtain the current temperature value of the plug; and,

[0021] Determine whether the current temperature value is greater than the temperature warning value;

[0022] If the value is greater than the threshold, the charging of the battery pack is interrupted; after a second time interval, the current temperature value of the plug is retrieved again, and the relationship between the current target temperature value and the temperature warning value is reassessed.

[0023] If the value is not greater than the threshold, continue charging the battery pack; after a second time interval, re-acquire the current temperature value of the plug and re-determine the relationship between the temperature value and the temperature warning value.

[0024] By adopting the above technical solution, a temperature sensor can be installed on the plug to detect its temperature. After the user completes the energy storage performance test of the battery pack, the user can connect the charging pile plug to the socket on the electric vehicle. At this time, the charging pile charges the battery pack. The temperature sensor detects the temperature of the plug just connected to the socket and records the detected temperature as the initial temperature value. The cloud obtains a temperature warning value based on the initial temperature value. After the charging pile charges the battery pack through the plug and a second period of time has passed, the cloud obtains the current temperature value sent by the temperature sensor. The cloud compares the temperature value with the temperature warning value to determine whether the temperature value is greater than the temperature warning value. When the cloud determines that the temperature value is greater than the temperature warning value, the cloud controls the charging pile to stop charging the battery pack. This can avoid the possibility of damage to the battery pack due to excessive temperature.

[0025] Optionally, after determining that the current temperature value is not greater than the temperature warning value, the method further includes:

[0026] The temperature difference between the two is obtained based on the current temperature value and the initial temperature value;

[0027] Determine whether the temperature difference is greater than a preset difference; if it is, reduce the current used to charge the battery pack.

[0028] By adopting the above technical solution, the electric vehicle may be in motion before charging, and the battery pack is already at a high temperature due to external power supply. The cloud obtains the temperature difference between the current temperature value and the initial temperature value. If the temperature difference is greater than the preset difference, the cloud controls the charging pile to reduce the current for charging the battery pack, thereby preventing the battery pack temperature from rising continuously.

[0029] Optionally, the detection method further includes a curve matching step;

[0030] Before charging the battery pack, obtain information about the type of battery pack;

[0031] Based on the aforementioned type information, the ideal current curve and ideal voltage curve of the battery pack are obtained.

[0032] During the charging process of the battery pack, the charging current value and the charging voltage value at both ends of the battery pack are acquired in real time.

[0033] An actual current curve is constructed based on the obtained charging current value, and an actual voltage curve is constructed based on the obtained charging voltage value.

[0034] The voltage phase difference between the two is obtained based on the actual current curve and the ideal current curve, and the voltage phase difference between the two is obtained based on the actual voltage curve and the ideal voltage curve.

[0035] When the voltage phase difference is greater than a preset first phase difference, and / or the current phase difference is greater than a preset second phase difference, a second prompt message is sent to the smart terminal bound to the battery pack.

[0036] By adopting the above technical solution, the charging process of a battery pack typically includes three processes: constant current, constant voltage, and trickle charging. Different types of batteries have different charging curves. After obtaining the type information of the battery pack, the cloud obtains the ideal current curve and ideal voltage curve for that type of battery pack. The actual voltage curve is compared with the ideal voltage curve, and the actual current curve is compared with the ideal current curve. When the voltage difference between the actual voltage curve and the ideal voltage curve is greater than a preset first difference, and / or the current difference between the actual current curve and the ideal current curve is greater than a preset second difference, the cloud issues a second prompt to the smart terminal bound to the battery pack, thereby better protecting the battery.

[0037] Optionally, the detection method further includes: sending the data generated and retrieved in at least one of the energy storage performance detection step, charging temperature monitoring step, and curve matching step to a smart terminal bound to the battery pack in real time.

[0038] Optionally, the detection method further includes: comparing the current voltage difference with voltage differences in historical data;

[0039] If the difference between the current voltage difference and a certain voltage difference in historical data is greater than a preset second difference, then a third prompt message is pushed to the smart terminal bound to the battery pack.

[0040] By adopting the above technical solution, after the user scans the code to bind the device, the cloud can obtain the user's historical data based on the user's information. The cloud compares the current voltage difference with the voltage difference in the historical data. If the difference between the current voltage difference and a certain voltage difference in the historical data is greater than a preset second difference, it indicates that the voltage drop of the battery pack has increased, which may be due to the aging of the battery pack. Therefore, the cloud pushes a third prompt message to the smart terminal bound to the battery pack to remind the user.

[0041] Optionally, the voltage value of the battery pack is detected by a detection circuit on the charging pile, the detection circuit including:

[0042] MCU;

[0043] The voltage acquisition module is used to detect the voltage across the battery pack and send the detected voltage value to the MCU;

[0044] A capacitor charging and discharging module is used to store the electrical energy output from the battery pack; and,

[0045] The first switch module communicates with the MCU, and the MCU controls the opening and closing of the first switch module, thereby controlling the capacitor charging and discharging module to charge.

[0046] Secondly, the battery pack testing system provided in this application adopts the following technical solution.

[0047] A battery pack testing system, comprising:

[0048] The first acquisition module is used to acquire the initial voltage value of the battery pack and obtain the rated full-load voltage of the battery pack based on the initial voltage value;

[0049] The second acquisition module is used to acquire the voltage values ​​of a preset number of batteries after the battery pack has been discharged for a first period of time.

[0050] The voltage value setting module is used to set the lowest voltage value as the voltage value to be detected;

[0051] The difference acquisition module is used to obtain the voltage difference between the initial voltage value and the voltage value to be detected;

[0052] The differential pressure value acquisition module is used to obtain the differential pressure value based on the rated full-load voltage.

[0053] The first judgment module is used to determine whether the voltage difference is greater than the judgment voltage difference value;

[0054] A relative difference acquisition module is used to obtain the relative difference between the voltage difference and the determined voltage difference;

[0055] The second judgment module is used to determine whether the relative difference is greater than the first deviation value; and

[0056] The first prompt message sending module is used to send the first prompt message to the smart terminal bound to the battery pack. Attached Figure Description

[0057] Figure 1 This is a flowchart of one embodiment of a battery pack testing method according to this application;

[0058] Figure 2 This is a schematic diagram of the circuit structure of the detection circuit in this application;

[0059] Figure 3This is a flowchart of some steps of another embodiment of a battery pack testing method of this application;

[0060] Figure 4 This is a system block diagram of one embodiment of a battery pack testing system according to this application;

[0061] In the diagram, 1 is the voltage acquisition module; 2 is the capacitor charging and discharging module; 3 is the first switch module; 4 is the load module; 5 is the second switch module; 6 is the current detection module; 7 is the first acquisition module; 8 is the second acquisition module; 9 is the voltage value setting module; 10 is the difference acquisition module; 11 is the differential voltage value acquisition module; 12 is the first judgment module; 13 is the relative difference acquisition module; 14 is the second judgment module; and 15 is the first prompt information sending module. Detailed Implementation

[0062] To make the purpose, technical solution, and advantages of this application clearer, the following description is provided in conjunction with the appendix. Figure 1-3 The present application will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the application.

[0063] This application provides a battery pack testing method, including an energy storage performance testing step; the energy storage performance testing step includes the following steps:

[0064] Step S101: Obtain the initial voltage value of the battery pack and obtain the rated full-load voltage of the battery pack based on the initial voltage value.

[0065] Specifically, before charging the battery pack of an electric vehicle, the user can first perform an energy storage performance test on the battery pack. The initial voltage value of the battery pack can be obtained through a detection circuit installed next to the charging station. Generally, the rated voltage of a single battery is 12V. The overall voltage and capacity of the battery pack will vary depending on the number of batteries. For example, if the initial voltage value of the battery pack is detected as 46V, then the rated full-load voltage of the battery pack is 48V. When a 48V battery pack and a 60V battery pack are discharged for the same amount of time, their voltage drops will be different. Step S101 can be executed by the charging station's controller or by the cloud (cloud server). If step S101 is executed by the charging station's controller, it specifically involves the charging station's controller obtaining the initial voltage value of the battery pack and determining the rated full-load voltage of the battery pack based on this initial voltage value. If step S101 is executed by the cloud, then specifically: the charging pile sends the detected initial voltage value of the battery pack to the cloud, and after the cloud obtains the initial voltage value of the battery pack, it obtains the rated full-load voltage of the battery pack based on the initial voltage value.

[0066] Step S102: After the battery pack has been discharged for a first period of time, obtain the voltage values ​​of a preset number of batteries in the battery pack.

[0067] Specifically, the voltage of the battery pack decreases when it discharges (i.e., when the battery pack supplies power to the outside). The first duration is preset and can be one minute or any other duration. Step S102 can be that the cloud sends a control command to the detection circuit on the charging pile, which then controls the battery pack to supply power; or the controller of the charging pile controls the aforementioned detection circuit to enable the battery pack to supply power. After the first duration, the charging pile collects a preset number of voltage values ​​of the battery pack after discharge through the detection circuit.

[0068] Step S103: Set the lowest voltage value as the voltage value to be detected.

[0069] Specifically, step S103 can be that the charging pile controller sets the lowest voltage value as the voltage value to be detected based on the preset number of collected voltage values. Alternatively, step S103 can be that the charging pile uploads the preset number of voltage values ​​to the cloud, where the cloud processes the data and sets the lowest voltage value as the voltage value to be detected.

[0070] Step S104: Calculate the voltage difference between the initial voltage value and the voltage value to be detected.

[0071] Specifically, subtracting the initial voltage value from the voltage value to be detected yields the voltage difference between the two. If step S104 is executed in the charging pile's controller, then step S104 specifically involves the charging pile's controller obtaining the voltage difference between the initial voltage value and the voltage value to be detected. If step S104 is executed in the cloud, then step S104 specifically involves the cloud obtaining the voltage difference between the initial voltage value and the voltage value to be detected.

[0072] Step S105: Obtain the differential voltage value based on the rated full-load voltage.

[0073] Specifically, because battery banks are non-linear components, even with the same number of batteries, under the same power supply duration, a battery bank with reduced energy storage performance (e.g., battery aging) will experience a greater voltage drop compared to a normal battery bank. Conversely, for battery banks with the same energy storage performance, under the same power supply duration, a battery bank with more batteries will experience a smaller voltage drop compared to a battery bank with fewer batteries. Therefore, a differential voltage value is needed. This differential voltage value is obtained through prior experiments and stored in a cloud database. The differential voltage value corresponds to the rated full-load voltage. After obtaining the rated full-load voltage in the cloud, the differential voltage value is obtained by comparing it with the data in the database.

[0074] Step S106: Determine whether the voltage difference is greater than the judgment voltage difference value; if so, proceed to step S107.

[0075] Specifically, the cloud-based system determines the relationship between the obtained voltage difference and the determined voltage difference.

[0076] Step S107: Obtain the relative difference between the voltage difference and the determined voltage difference.

[0077] Step S108: Determine whether the relative difference is greater than the first deviation value; if so, proceed to step S108.

[0078] Specifically, various factors (such as ambient temperature) can interfere with the supply of power from battery banks, making it difficult for the voltage difference to perfectly match the target voltage difference. As long as the deviation between the voltage difference and the target voltage difference is within a certain range, the energy storage performance of the battery bank can be considered good. Therefore, a first deviation value is set. This first deviation value is obtained through prior experiments and stored in a cloud database. Different types of battery banks have different first deviation values; battery banks with different numbers of batteries also have different first deviation values. The cloud system determines whether the relative difference is greater than the first deviation value.

[0079] Step S109: Send the first prompt message to the smart terminal bound to the battery pack.

[0080] Specifically, if the relative difference exceeds the first deviation value, the cloud will send a first alert message to the smart terminal bound to the battery pack. This first alert message is used to notify the user that the battery pack's energy storage performance has decreased. The first alert message can be pushed from the cloud to an app on the user's smart terminal, a mini-program on the user's smart terminal, or a web link to the user's smart terminal.

[0081] As another implementation method for energy storage performance testing, the smart terminal bound to the battery pack is bound by the user through a QR code scan.

[0082] Specifically, a QR code can be affixed to the charging station. Users can scan the QR code with their smart devices to bind their identity, thereby linking the user's identity to the battery pack. Regardless of which charging station a user uses, the cloud can access the user's historical data and save and push all data from the usage process to the user's smart device.

[0083] Reference Figure 2 The voltage value of the battery pack is realized through the detection circuit on the charging pile. The detection circuit includes: MCU, voltage acquisition module 1, capacitor charging and discharging module 2 and first switch module 3.

[0084] Specifically, the MCU can be located within the charging pile's controller or can be a separate component independent of the charging pile's controller. The MCU is responsible for the logic control and data processing of the detection circuit. Voltage acquisition module 1 detects the voltage across the battery pack and sends the detected voltage value to the MCU. Capacitor charging / discharging module 2 stores the electrical energy output from the battery pack. In this embodiment, capacitor charging / discharging module 2 includes a first capacitor C1, which is connected in series with the battery pack of the electric vehicle. First switch module 3 communicates with the MCU, and the MCU controls the opening and closing of the first switch module 3. In this embodiment, the first switch module 3 includes a first wireless switch S1, which is connected in series with the first capacitor C1. The MCU controls the opening and closing of the first wireless switch S1, thereby controlling the battery pack to charge capacitor charging / discharging module 2.

[0085] When using a detection circuit to test the energy storage performance of the battery pack of an electric vehicle, the connector of this embodiment is connected to the socket of the electric vehicle, and the initial voltage value of the battery pack is detected by the voltage acquisition module 1.

[0086] Continue to refer to Figure 2 To facilitate the discharge of the capacitor charging / discharging module 2, the detection circuit also includes a load module 4 and a second switch module 5. The load module 4 is connected in parallel with the capacitor charging / discharging module 2 and is used to consume the electrical energy stored in the capacitor charging / discharging module 2. The second switch module 5 is connected to the load module 4 and communicates with the MCU, which controls the opening and closing of the second switch module 5.

[0087] In this embodiment, the load module 4 includes a first resistor R1, which is connected in parallel with the first capacitor C1. The second switch module 5 includes a second wireless switch S2, which is connected in series with the first resistor R1. When the energy storage performance of the battery pack is tested, the MCU controls the first wireless switch S1 to close and the second wireless switch S2 to open. At this time, the battery pack only charges the capacitor charging and discharging module 2. When the energy storage performance test of the battery pack is completed, the MCU controls the first wireless switch S1 to open and the second wireless switch S2 to close. The first capacitor C1 supplies power to the first resistor R1, thereby consuming the energy of the first capacitor C1. This allows the detection circuit to be reused and enables energy storage performance testing of different battery packs.

[0088] Continue to refer to Figure 2To obtain more accurate detection results, the detection circuit also includes a current detection module 6. This module detects the magnitude of the current output by the battery pack and sends the detected current value to the cloud. The current detection module 6 can be a Hall effect current sensor. The Hall effect current sensor sends the detected current value to the cloud, which plots the current value during battery pack discharge as a current curve and compares it with a pre-stored current curve. If the circuit curve differs significantly from the current curve of a normal battery pack, it indicates a performance degradation in the battery pack, thus enabling more accurate detection of whether the battery pack has reduced energy storage performance.

[0089] Reference Figure 3 As another implementation of a battery pack testing method, the testing method further includes a charging temperature monitoring step, which includes the following steps:

[0090] Step S201: When the plug is connected to the socket of the electric vehicle and the battery pack is charging, obtain the initial temperature of the plug and obtain the temperature warning value based on the initial temperature.

[0091] Specifically, when the charging pile is connected to the electric vehicle's socket and the battery pack is charging, the cloud sends an activation message to the charging pile. The charging pile then activates its indicator light based on this message. This indicator light shows the charging status of the battery pack; for example, it may be red while charging and green when fully charged. A temperature sensor can be installed on the charging pile's plug to detect its temperature. After the user completes the battery pack's energy storage performance testing, they can connect the charging pile to the electric vehicle's socket. The charging pile then charges the battery pack, and simultaneously, the cloud sends a control command to the charging pile to activate the temperature sensor. The sensor detects the temperature of the plug just connected to the socket and records the detected temperature as the initial temperature value. The charging pile sends this initial temperature value to the cloud, which then calculates a temperature warning value. This warning value is obtained by adding a fixed value to the initial temperature value. This fixed value is determined based on the battery pack's performance degradation observed during the energy storage performance testing and the battery pack's rated full-load voltage. For example, a battery pack with reduced performance is prone to increased internal resistance and heat generation during charging; when the energy storage performance of the battery pack decreases, this fixed value increases, that is, the temperature warning value increases.

[0092] Step S202: After a second time interval, obtain the current temperature value of the plug.

[0093] Specifically, after the charging pile charges the battery pack through the plug and a second time interval has elapsed, the cloud sends an activation signal to the temperature sensor again. That is, step S202 can be: after a second time interval, an activation signal is sent to the temperature sensor, the temperature sensor re-detects the temperature of the plug, and the cloud obtains the current temperature value sent by the temperature sensor.

[0094] Step S203: Determine if the current temperature value is greater than the temperature warning value; if it is, proceed to step S204. If it is not, proceed to step S205.

[0095] Specifically, the cloud compares the temperature value with the temperature warning value to determine whether the temperature value exceeds the temperature warning value.

[0096] Step S204: Interrupt the charging of the battery pack; after a second time interval, reacquire the current temperature value of the plug and re-determine the relationship between the temperature value and the temperature warning value.

[0097] Specifically, since the plug connects to the socket, and the socket connects to the battery pack, some heat from the battery is conducted to the plug. When the cloud determines that the temperature exceeds the temperature warning threshold, it controls the charging station to stop charging the battery pack. This prevents potential damage to the battery pack due to overheating and also avoids damage caused by abnormal charging. After the battery pack has been off-charge for a certain period, the cloud sends a restart command to the charging station to activate the temperature sensor. The temperature sensor then re-collects the current plug temperature and sends the value back to the cloud. The cloud then compares the current temperature value with the temperature warning threshold to determine whether to supply power to the battery pack.

[0098] Step S205: Continue charging the battery pack; after a second time interval, re-acquire the current temperature value of the plug and re-determine the relationship between the temperature value and the temperature warning value.

[0099] Specifically, if the current temperature value is not greater than the temperature warning value, the cloud-controlled charging pile continues to charge the battery pack. After a second interval, the temperature of the plug is retrieved again and compared with the temperature warning value to determine whether to continue charging the battery pack.

[0100] As another implementation method for battery pack testing, after determining that the temperature value is not greater than the temperature warning value, it also includes:

[0101] The temperature difference between the two is obtained based on the current temperature value and the initial temperature value;

[0102] Determine if the temperature difference is greater than a preset value; if it is, reduce the current used to charge the battery pack.

[0103] Specifically, before charging, the electric vehicle may be in motion, and the battery pack, due to supplying power to external sources, will already be at a high temperature. The cloud-based system calculates the temperature difference between the current and initial temperatures. If this temperature difference exceeds a preset threshold, while the current temperature may not cause battery pack failure, it could potentially reduce battery pack lifespan. If the battery pack continues to be charged at the original current, there is a high probability that the battery pack temperature will rise further. In this embodiment, the cloud-based system controls the charging station to reduce the current used to charge the battery pack, thereby preventing the battery pack temperature from continuously rising.

[0104] As another implementation of a battery pack testing method, the testing method further includes a curve matching step. The curve matching step includes:

[0105] Before charging the battery pack, obtain information about the type of battery pack.

[0106] Based on the type information, the ideal current curve and ideal voltage curve of the battery pack are obtained;

[0107] During the charging process of the battery pack, the charging current value and the charging voltage value at both ends of the battery pack are acquired in real time.

[0108] The actual current curve is constructed based on the obtained charging current value, and the actual voltage curve is constructed based on the obtained charging voltage value.

[0109] The voltage phase difference between the two is obtained based on the actual current curve and the ideal current curve, and the voltage phase difference between the two is obtained based on the actual voltage curve and the ideal voltage curve.

[0110] When the voltage phase difference is greater than the preset first phase difference, and / or the current phase difference is greater than the preset second phase difference, a second prompt message is sent to the smart terminal bound to the battery pack.

[0111] Specifically, users can input the battery pack type information via a button on the charging station. This button can be a physical button on the charging station or a virtual button. Battery pack types include lead-acid batteries and lithium iron phosphate batteries, among others. Generally, the charging process for a battery pack includes three stages: constant current, constant voltage, and trickle charging. Different types of batteries have different ideal charging curves. After obtaining the battery pack type information from the cloud, the ideal current curve and ideal voltage curve for that type of battery pack are obtained. These ideal current and voltage curves can be pre-stored in the cloud. The ideal current and voltage curves are obtained by processing the charging current and voltage curves of several normal battery packs during charging. This processing method can either remove curves with large deviations and then average the remaining curves, or select one of several curves with a high degree of overlap as the ideal charging curve.

[0112] The cloud compares the actual voltage curve with the ideal voltage curve and the actual current curve with the ideal current curve. When the voltage difference between the actual voltage curve and the ideal voltage curve is greater than the preset first difference, and / or the current difference between the actual current curve and the ideal current curve is greater than the preset second difference, the cloud sends a second prompt message to the smart terminal bound to the battery pack, thereby better protecting the battery.

[0113] As another implementation of a battery pack testing method, the testing method further includes sending the data generated and retrieved in at least one of the energy storage performance testing step, charging temperature monitoring step, and curve matching step to the cloud and / or the user's smart terminal.

[0114] Specifically, the data generated and retrieved in the energy storage performance testing step mainly includes the initial voltage value, the voltage value to be tested, the judgment voltage difference value, the relative difference between the voltage difference and the judgment voltage difference value, and the first warning information. The data generated and retrieved in the charging temperature monitoring step mainly includes the initial temperature value, temperature warning value, temperature value, and temperature difference. The data generated in the curve matching step mainly includes the actual voltage curve, actual current curve, ideal current curve, and ideal voltage curve. After these data are generated and retrieved, the cloud classifies and packages them. During the data generation process, the cloud can also push this data to the user's smart terminal in real time, allowing the user to instantly view various data related to the battery pack charging. The cloud can also store this data according to user information in a timely manner. Users can also retrieve various data stored in the cloud to view historical data, facilitating understanding of changes in the battery pack's data. The user's smart terminal includes, but is not limited to, smartphones, tablets, and smartwatches. Users can also instantly and intuitively view various data of the battery pack through an app or mini-program on their smart terminal.

[0115] As another implementation of a battery pack testing method, the testing method further includes: comparing the current voltage difference with the voltage difference in historical data;

[0116] If the difference between the current voltage difference and a certain voltage difference in historical data is greater than a preset second difference, then a third prompt message will be pushed to the smart terminal bound to the battery pack.

[0117] Specifically, after a user scans the code to bind their account, the cloud can obtain the user's historical data based on the user's information. The cloud compares the current voltage difference with the voltage difference in the historical data. If the difference between the current voltage difference and a certain voltage difference in the historical data is greater than a preset second difference, it indicates that the voltage drop of the battery pack has increased significantly, which may be due to the aging of the battery pack. Therefore, the cloud pushes a third prompt message to the smart terminal bound to the battery pack to remind the user.

[0118] This application also provides a battery pack testing system, including:

[0119] The first acquisition module 7 is used to acquire the initial voltage value of the battery pack and obtain the rated full-load voltage of the battery pack based on the initial voltage value.

[0120] The second acquisition module 8 is used to acquire the voltage values ​​of a preset number of batteries after the battery pack has been discharged for a first period of time.

[0121] The voltage value setting module 9 is used to set the lowest voltage value as the voltage value to be detected;

[0122] The difference acquisition module 10 is used to obtain the voltage difference between the initial voltage value and the voltage value to be detected.

[0123] The differential pressure value acquisition module 11 is used to obtain the differential pressure value based on the rated full-load voltage.

[0124] The first judgment module 12 is used to determine whether the voltage difference is greater than the judgment voltage difference value;

[0125] The relative difference acquisition module 13 is used to obtain the relative difference between the voltage difference and the determined voltage difference;

[0126] The second judgment module 14 is used to determine whether the relative difference is greater than the first deviation value; and

[0127] The first prompt message sending module 15 is used to send the first prompt message to the smart terminal bound to the battery pack.

[0128] The above are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Any feature disclosed in this specification (including the abstract and drawings) may be replaced by other equivalent or similar features unless specifically stated otherwise. That is, unless specifically stated otherwise, each feature is only one example of a series of equivalent or similar features.

Claims

1. A method for testing a battery pack, characterized in that, Includes energy storage performance testing steps; The energy storage performance testing steps include: Obtain the initial voltage value of the battery pack and calculate the rated full-load voltage of the battery pack based on the initial voltage value; After the battery pack has been discharged for a first period of time, the voltage values ​​of a preset number of batteries in the battery pack are obtained. Set the lowest voltage value as the voltage to be detected; The voltage difference between the initial voltage value and the voltage value to be detected is obtained. The differential voltage value is determined based on the rated full-load voltage. Determine whether the voltage difference is greater than the determined voltage difference value; if so, obtain the relative difference between the voltage difference and the determined voltage difference value; and, Determine whether the relative difference is greater than a first deviation value; if it is, send a first prompt message to the smart terminal bound to the battery pack; wherein, the first prompt message is used to prompt the user that the battery pack has reduced energy storage performance; The detection method further includes a charging temperature monitoring step, which includes: With the plug connected to the electric vehicle's socket and the battery pack charging, the initial temperature of the plug is obtained, and a temperature warning value is obtained based on the initial temperature. The temperature warning value is obtained by adding a fixed value to the initial temperature value. The fixed value is determined based on the performance degradation of the battery pack and the rated full-load voltage of the battery pack obtained in the energy storage performance testing step. When the energy storage performance of the battery pack decreases, the fixed value increases. After a second time interval, obtain the current temperature value of the plug; and, Determine whether the current temperature value is greater than the temperature warning value; If the temperature is greater than the warning value, the charging of the battery pack is interrupted; after a second time interval, the current temperature value of the plug is retrieved again, and it is re-determined whether the current temperature value is greater than the temperature warning value. If the value is not greater than the specified value, continue charging the battery pack; after a second time interval, re-acquire the current temperature value of the plug and re-determine the relationship between the temperature value and the temperature warning value. After determining that the current temperature value is not greater than the temperature warning value, the method further includes: The temperature difference between the two is obtained based on the current temperature value and the initial temperature value; Determine whether the temperature difference is greater than a preset difference; if it is, reduce the charging current for the battery pack. The detection method further includes a curve matching step; the curve matching step includes: Before charging the battery pack, obtain information about the type of battery pack; Based on the aforementioned type information, the ideal current curve and ideal voltage curve of the battery pack are obtained; wherein, the charging process of the battery pack includes three processes: constant current, constant voltage, and trickle charging, and the ideal charging curves are different for different types of battery packs; During the charging process of the battery pack, the charging current value and the charging voltage value at both ends of the battery pack are acquired in real time. An actual current curve is constructed based on the obtained charging current value, and an actual voltage curve is constructed based on the obtained charging voltage value. The current phase difference between the two is obtained based on the actual current curve and the ideal current curve, and the voltage phase difference between the two is obtained based on the actual voltage curve and the ideal voltage curve. When the voltage phase difference is greater than a preset first phase difference, and / or the current phase difference is greater than a preset second phase difference, a second prompt message is sent to the smart terminal bound to the battery pack.

2. The battery pack testing method according to claim 1, characterized in that, The smart terminal that is bound to the battery pack is bound by the user through scanning a code on the smart terminal.

3. The battery pack testing method according to claim 1, characterized in that, The detection method further includes: sending the data generated and called in at least one of the energy storage performance detection step, charging temperature monitoring step and curve matching step to the smart terminal bound to the battery pack in real time.

4. The battery pack testing method according to claim 1, characterized in that, The detection method further includes: comparing the current voltage difference with the voltage difference in historical data; If the difference between the current voltage difference and a certain voltage difference in historical data is greater than a preset second difference, then a third prompt message is pushed to the smart terminal bound to the battery pack.

5. The battery pack testing method according to claim 1, characterized in that: The voltage value of the battery pack is detected by a detection circuit on the charging station, which includes: MCU; The voltage acquisition module (1) is used to detect the voltage across the battery pack and send the detected voltage value to the MCU; A capacitor charging and discharging module (2) is used to store the electrical energy output by the battery pack; and, The first switch module (3) communicates with the MCU, and the MCU controls the opening and closing of the first switch module (3) to control the capacitor charging and discharging module (2) to charge.

6. A battery pack testing system, used to execute the battery pack testing method according to any one of claims 1 to 5, characterized in that, include: The first acquisition module (7) is used to acquire the initial voltage value of the battery pack and obtain the rated full-load voltage of the battery pack based on the initial voltage value; The second acquisition module (8) is used to acquire the voltage values ​​of a preset number of batteries after the battery pack has been discharged and a first time has elapsed. The voltage value setting module (9) is used to set the lowest voltage value as the voltage value to be detected; The difference acquisition module (10) is used to obtain the voltage difference between the initial voltage value and the voltage value to be detected; The differential pressure value acquisition module (11) is used to obtain the differential pressure value based on the rated full-load voltage. The first judgment module (12) is used to determine whether the voltage difference is greater than the judgment voltage difference value; The relative difference acquisition module (13) is used to obtain the relative difference between the voltage difference and the determination voltage difference when the voltage difference is greater than the determination voltage difference value; The second judgment module (14) is used to determine whether the relative difference is greater than the first deviation value; as well as, The first prompt message sending module (15) is used to send a first prompt message to the smart terminal bound to the battery pack when the relative difference is greater than the first deviation value; wherein, the first prompt message is used to prompt the user that the energy storage performance of the battery pack has decreased; It also includes a charging temperature monitoring module, which is configured as follows: With the plug connected to the electric vehicle's socket and the battery pack charging, the initial temperature of the plug is obtained, and a temperature warning value is obtained based on the initial temperature. The temperature warning value is obtained by adding a fixed value to the initial temperature value. The fixed value is determined based on the performance degradation of the battery pack and the rated full-load voltage of the battery pack obtained in the energy storage performance testing step. When the energy storage performance of the battery pack decreases, the fixed value increases. After a second time interval, obtain the current temperature value of the plug; and, Determine whether the current temperature value is greater than the temperature warning value; If the temperature is greater than the warning value, the charging of the battery pack is interrupted; after a second time interval, the current temperature value of the plug is retrieved again, and it is re-determined whether the current temperature value is greater than the temperature warning value. If the value is not greater than the specified value, continue charging the battery pack; after a second time interval, re-acquire the current temperature value of the plug and re-determine the relationship between the temperature value and the temperature warning value. After determining that the current temperature value is not greater than the temperature warning value, the method further includes: The temperature difference between the two is obtained based on the current temperature value and the initial temperature value; Determine whether the temperature difference is greater than a preset difference; if it is, reduce the charging current for the battery pack. It also includes a curve matching module, which is configured as follows: Before charging the battery pack, obtain information about the type of battery pack; Based on the aforementioned type information, the ideal current curve and ideal voltage curve of the battery pack are obtained; wherein, the charging process of the battery pack includes three processes: constant current, constant voltage, and trickle charging, and the ideal charging curves are different for different types of battery packs; During the charging process of the battery pack, the charging current value and the charging voltage value at both ends of the battery pack are acquired in real time. An actual current curve is constructed based on the obtained charging current value, and an actual voltage curve is constructed based on the obtained charging voltage value. The current phase difference between the two is obtained based on the actual current curve and the ideal current curve, and the voltage phase difference between the two is obtained based on the actual voltage curve and the ideal voltage curve. When the voltage phase difference is greater than a preset first phase difference, and / or the current phase difference is greater than a preset second phase difference, a second prompt message is sent to the smart terminal bound to the battery pack.

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