A battery detection method and apparatus

Abstract

The application discloses a battery detection method and device, the method comprises the following steps: determining a first loading parameter of a first pulse current; loading the first pulse current on a to-be-detected battery based on the first loading parameter, so as to obtain a first change rate of a voltage of the to-be-detected battery; and determining whether internal short circuit of the to-be-detected battery occurs based on the first change rate.

Description

Technical Field

[0001] This application relates to the field of battery technology, and to, but is not limited to, a battery testing method and apparatus. Background Technology

[0002] Macroscopically, internal short circuits (ISCs) in batteries can be divided into soft short circuits and hard short circuits. A soft short circuit (SSC) occurs when both lithium ions and electrons are transported within the battery, usually due to internal overcharging or over-discharging. Battery failure caused by a soft short circuit is unlikely to lead to catastrophic consequences, but its characteristics are extremely subtle. A hard short circuit (HSC) occurs when only electrons are transported within the battery, usually caused by external puncture, and has a higher short-circuit current density. Hard short circuits cause faster localized temperature rise in the battery, making it very prone to catastrophic consequences such as thermal runaway. Its characteristics are easily detected.

[0003] For customers using portable devices, collisions, drops, and crushes are common occurrences, which can structurally cause internal short circuits in the battery. However, these soft short circuits do not immediately lead to thermal runaway; they only occur under accumulated conditions over time. Especially given the long usage cycles of portable devices, repeated overcharging and over-discharging can also cause internal soft short circuits, increasing safety risks. In short, soft short circuits are very common in portable devices but are difficult to detect, posing a safety hazard to users. Summary of the Invention

[0004] In view of this, embodiments of this application provide a battery detection method and apparatus.

[0005] In a first aspect, embodiments of this application provide a battery detection method, the method comprising: determining a first loading parameter of a first pulse current; loading the first pulse current onto the battery under test based on the first loading parameter to obtain a first rate of change of voltage of the battery under test; and determining whether the battery under test has an internal short circuit based on the first rate of change.

[0006] Secondly, embodiments of this application provide a battery testing device, comprising: a first determining module, configured to determine a first loading parameter of a first pulse current; a first loading module, configured to load the first pulse current onto the battery under test based on the first loading parameter, thereby obtaining a first rate of change of voltage of the battery under test; and an analysis module, configured to determine whether the battery under test has experienced an internal short circuit based on the first rate of change.

[0007] In this embodiment, the first rate of change of the voltage of the battery under test is obtained by applying a first pulse current with a first loading parameter to the battery under test. This allows for the determination of an internal short circuit in the battery under test when the rate of change of the voltage changes during the amplification of leakage charge reaction. This enables a more timely, efficient, accurate, concise, and intuitive determination of whether an internal short circuit has occurred in the battery under test. Attached Figure Description

[0008] Figure 1 This is a schematic flowchart of a battery detection method according to an embodiment of this application;

[0009] Figure 2 This is a schematic diagram illustrating the relationship between battery voltage and short-circuit resistance according to an embodiment of this application;

[0010] Figure 3 This is a schematic diagram of an equivalent circuit for charging state according to an embodiment of this application;

[0011] Figure 4 This is a schematic diagram of an equivalent circuit for a discharge state according to an embodiment of this application;

[0012] Figure 5 This is a schematic diagram of a battery charge-discharge curve according to an embodiment of this application;

[0013] Figure 6 This is a schematic diagram of another battery charge-discharge curve according to an embodiment of this application;

[0014] Figure 7 This is a schematic diagram of the detection logic flow of a battery under test according to an embodiment of this application;

[0015] Figure 8 This is a schematic diagram of the composition structure of a battery detection device according to an embodiment of this application;

[0016] Figure 9 This is a schematic diagram of a hardware entity of an electronic device according to an embodiment of this application. Detailed Implementation

[0017] The technical solution of this application will be further described in detail below with reference to the accompanying drawings and embodiments.

[0018] Figure 1 This is a schematic flowchart of a battery detection method according to an embodiment of this application, as shown below. Figure 1 As shown, the method includes the following steps:

[0019] Step S102: Determine the first loading parameters of the first pulse current;

[0020] The first loading parameters may include the current intensity, current loading time, current loading frequency, and cutoff voltage of the battery under test of the first pulse current to be loaded; the current intensity may be expressed as I, and may be 0.1C (C is the charge / discharge rate), 0.3C, 0.5C, 1C, 2C, etc.; the current loading time may be expressed as t, and may be 1 second (unit: s), 10s, 1 minute (unit: min), etc.; the current loading frequency may be expressed as f; and the cutoff voltage may be expressed as U, and the cutoff voltage during charging may be 4.2 volts (unit: V), 4.3V, 4.4V, etc., and the cutoff voltage during discharging may be 3.4V, 3.2V, 3.0V, etc.

[0021] Step S104: Apply the first pulse current to the battery under test based on the first loading parameters to obtain the first rate of change of the voltage of the battery under test;

[0022] One method is to apply a first pulse current to the battery under test to perform pulse charging or pulse discharging, thereby obtaining the rate of change of the battery's voltage during charging or discharging.

[0023] Step S106: Based on the first rate of change, determine whether the battery under test has an internal short circuit.

[0024] In typical commercial portable batteries, the short-circuit resistance of a normal battery is considered infinite, while the short-circuit resistance of a failed battery is approximately 3Ω to 20Ω. This can be understood as any short circuit with a resistance higher than a certain threshold being considered a soft short circuit, and those below this threshold being considered a hard short circuit. For example... Figure 2 As shown, 21 is the voltage curve of a normal battery, 22 is the voltage curve of a short-circuited battery, 221 is the soft short-circuit stage of a short-circuited battery, and 222 is the hard short-circuit stage of a short-circuited battery. During a soft short circuit, the short-circuit resistance of the short-circuited battery is very large, which means that the voltage of the soft short-circuited battery is not much different from that of a healthy battery, making it difficult to detect whether a soft short circuit has occurred by voltage alone. During a hard short circuit, the voltage drop is very obvious, and it can be judged by any one of the short-circuit resistance, voltage, or temperature. However, at this time, there is already a risk of thermal runaway, and it is too late to issue a warning.

[0025] Therefore, early detection of internal short circuits in batteries can warn users and prevent catastrophic events.

[0026] Since a battery with an internal short circuit will generate leakage current, which will occupy the battery's charging / discharging capacity and change the rate of change of the battery's voltage, and pulse current has the effect of amplifying the leakage charge reaction, by applying a pulse current to the battery under test, the rate of change of the battery's voltage under the pulse current can be used to detect whether the battery under test has an internal short circuit.

[0027] In this embodiment, the first rate of change of the voltage of the battery under test is obtained by applying a first pulse current with a first loading parameter to the battery under test. This allows for the determination of an internal short circuit in the battery under test when the rate of change of the voltage changes during the amplification of leakage charge reaction. This enables a more timely, efficient, accurate, concise, and intuitive determination of whether an internal short circuit has occurred in the battery under test.

[0028] In some embodiments, the method further includes the steps S1011 and S1012:

[0029] Step S1011: Determine the first scenario in which the battery under test is located;

[0030] Step S1012: Determine the first loading parameter of the first pulse current based on the first scenario;

[0031] Wherein: the first scenario is associated with at least one of the following parameters:

[0032] The state of charge of the battery under test;

[0033] The charge / discharge rate of the battery under test;

[0034] The temperature of the battery to be tested.

[0035] The state of charge (SOC) can be represented as SOC, reflecting the ratio of the remaining capacity of the battery under test to its capacity in a fully charged state. The charge / discharge rate of the battery under test is numerically equal to a multiple of the battery's rated capacity, and can be represented as C, where charge / discharge rate = charge / discharge current / rated capacity. The temperature can be represented as T. Different combinations of SOC, charge / discharge rates, and temperatures can form different first scenarios. In some embodiments, the first scenario can also be related to the aging degree of the battery under test. The first loading parameter of the first pulse current applied to the battery under test can be different under different first scenarios. In each first scenario, pulse currents with different first loading parameters can be applied to a certain type of battery multiple times until a pulse current with loading parameters that can amplify the leakage charge effect to the limit without current overload is found. The loading parameter is then determined as the first loading parameter of the first pulse current for that type of battery in the first scenario.

[0036] In this embodiment of the application, by determining the first scenario of the battery under test, determining the first loading parameter of the first pulse current, and obtaining the voltage change rate of the battery under test under the corresponding first loading parameter, the first scenario, the first loading parameter, and the first change rate can be associated, and the appropriate loading parameter can be determined for different scenarios more accurately, and the voltage change rate under different loading parameters can be determined more accurately.

[0037] In some embodiments, step S1012, "determining the first loading parameter of the first pulse current based on the first scenario," may include:

[0038] Based on the first scenario, determine the current intensity and current loading time of the first pulse current, or the current intensity and the cutoff voltage of the battery under test;

[0039] Correspondingly, step S104, "applying the first pulse current to the battery under test based on the first loading parameters to obtain the first rate of change of the voltage of the battery under test," may include the following steps S1041 or S1042:

[0040] Step S1041: Obtain the first rate of change of the voltage of the battery under test based on the current intensity and the current loading time;

[0041] The current loading time can be defined as t. Within the current loading time range, the voltage change ΔV of the battery under test under the current intensity is determined. Based on the ratio of the voltage change to the current loading time, the first rate of change k of the voltage of the battery under test is obtained, i.e., k = ΔV / t.

[0042] Step S1042: Based on the current intensity and the cutoff voltage of the battery under test, obtain the first rate of change of the voltage of the battery under test.

[0043] Furthermore, a cutoff voltage V1 can be specified, and the time Δt for the battery under test to change from the initial voltage V0 to the cutoff voltage V1 under the current intensity can be determined. Based on the change in voltage from the initial voltage to the cutoff voltage V1 and the time Δt, the first rate of change of voltage k of the battery under test is obtained, i.e., k = (V1 - V0) / Δt.

[0044] It can be seen that both steps S1041 and S1042 can represent the slope of the voltage-time curve of the battery under test.

[0045] In this embodiment, the voltage change rate can be determined either by the current intensity and the current loading time, or by the current intensity and the cutoff voltage of the battery under test, thus improving the flexibility and versatility of voltage change rate determination.

[0046] In some embodiments, step S106, "determining whether the battery under test has an internal short circuit based on the first rate of change," can be implemented through the following steps S1061 and S1062:

[0047] Step S1061: Determine the target scene corresponding to the first scene;

[0048] Step S1062: Compare the first rate of change with the first target rate of change corresponding to the target scenario to determine whether the battery under test has an internal short circuit, wherein the target scenario is a preset scenario in the standard database.

[0049] The target scenario can be a preset scenario in the standard library that is consistent with the first scenario (i.e., the same or highly similar). The first target change rate can be the voltage change rate of a normal battery without an internal short circuit. Since the leakage current generated by the internal short circuit will change the voltage change rate of the battery, by comparing the first change rate of the battery under test with the first target change rate of the normal battery, it can be determined whether the battery under test has an internal short circuit.

[0050] In this embodiment of the application, by comparing the first rate of change with the first target rate of change of a normal battery in the target scenario corresponding to the standard database, it is possible to determine whether the battery under test has an internal short circuit in a more timely, accurate, efficient and convenient manner.

[0051] In some embodiments, the method further includes the following steps S1001 to S1004:

[0052] Step S1001: Determine multiple different preset scenarios;

[0053] Step S1002: Determine the second loading parameters of the second pulse current based on each of the preset scenarios;

[0054] Step S1003: Apply the second pulse current to the normal battery based on the second loading parameters to obtain the first target rate of change of the voltage of the normal battery; the normal battery is a battery that has not experienced an internal short circuit;

[0055] Step S1004: Apply the second pulse current to multiple different short-circuited batteries based on the second loading parameters to obtain the second target rate of change of voltage for each short-circuited battery; the short-circuited battery is a battery that has experienced an internal short circuit; different short-circuited batteries have different short-circuit resistances;

[0056] Wherein: the preset scenario in which the normal battery / short-circuit battery is located is associated with at least one of the following parameters: the state of charge of the normal battery / short-circuit battery; the charge / discharge rate of the normal battery / short-circuit battery; and the temperature of the normal battery / short-circuit battery.

[0057] To better understand the impact of different short-circuit conditions on the battery, the behavior of an internal short circuit can be simulated by using shunt resistors at the battery terminals. The degree of short circuit in a short-circuited battery can be quantified by the magnitude of its short-circuit resistance or voltage change rate.

[0058] From such Figure 3 The equivalent circuit for the charging state shown can be used to obtain the following formulas (1) and (2):

[0059] I total =I battery +I short ……(1);

[0060] V total =V OCV +R battery ×I battery =R short ×I short ……(2);

[0061] Among them, I total I represents the pulse current applied to the short-circuited battery during the charging phase. short This represents the short-circuit current, also known as leakage current, I. battery This indicates the current flowing to the short-circuited battery; V OCV R represents the terminal voltage of the short-circuited battery in the open-circuit state. battery R represents the internal resistance of a short-circuited battery. short This represents the resistance of the shunt at the simulated short circuit point. V total This indicates the voltage of the short-circuited battery.

[0062] By combining formulas (1) and (2), I can be eliminated. short Formula (3) can be obtained:

[0063]

[0064] At this time, the voltage V of a normal battery total-normal This can be expressed by formula (4):

[0065] V total-normal =V OCV +R battery ×I total ……(4);

[0066] Comparing and subtracting formulas (3) and (4), we can obtain the voltage difference ΔV1 between the short-circuited battery and the normal battery under the condition of applied charging current:

[0067]

[0068] From formula (5), it can be seen that when the applied current I total The larger the value, the greater the voltage difference ΔV1 between the short-circuited battery and the normal battery. In other words, the pulse current amplifies this leakage charge reaction. Furthermore, detection (V) under near-fully charged conditions (i.e., state of charge close to 100%)... OCV The larger the value, the greater the voltage difference.

[0069] Furthermore, as shown in formula (5), when the same pulse current is applied, the voltage V of the short-circuited battery is... total Less than the voltage V of a normal battery total .

[0070] Assuming the battery's internal resistance is 50 milliohms (mΩ), the battery's open-circuit voltage V OCV When the applied charging current I is 3.8V total The battery voltage V is measured after a period of time Δt, with a current of 8 amps (A). total V OCV =3.8V, I total =8A,R battery =50mΩ.

[0071] For a normal battery, R short →∞,V total-normal =V OCV +R battery ×I total =3.8 + 0.05 × 8 = 4.2V; For a short-circuited battery, R short =20Ω, That is, when the same pulse current is applied, the voltage of the short-circuited battery is less than the voltage of the normal battery.

[0072] Understandably, if an internal short circuit occurs in the battery, due to the presence of leakage current, when the same pulse current is applied during the charging phase, the total power supply not only needs to charge the battery, but also a portion of the current is diverted to the short circuit site for heat generation. This results in a smaller voltage increase (i.e., the rate of voltage change) per unit time.

[0073] like Figure 5 As shown, in a certain preset scenario, the applied second pulse current can be 0.5C. During the charging phase, solid line 501 represents the voltage curve of a normal battery, while dashed lines 502 and 503 represent the voltage curves of short-circuited batteries with different short-circuit resistances. The internal resistance of a normal battery tends towards positive infinity and can be expressed as R. short →∞, the short-circuit resistance of the short-circuit battery corresponding to dashed line 503 is less than the short-circuit resistance of the short-circuit battery corresponding to dashed line 502.

[0074] During the charging phase, the voltage of the short-circuited battery is lower than that of the normal battery. That is, the voltage curve of the short-circuited battery is below that of the normal battery. The more severe the short circuit, the lower the voltage of the short-circuited battery, that is, the lower the voltage curve is. This is manifested as a gentler slope of the voltage curve. The short-circuited battery corresponding to dashed line 503 is more severely short-circuited than the short-circuited battery corresponding to dashed line 502.

[0075] Similarly, from such Figure 4The equivalent circuit of the discharge state shown can be used to obtain the following formulas (6) and (7):

[0076] I battery =I total +I short ...(6);

[0077] V total =V OCV +R battery ×I battery =R short ×I short ……(7);

[0078] By combining formulas (6) and (7), I can be eliminated. short Formula (8) can be obtained:

[0079]

[0080] Normal battery R short →∞, at this time

[0081] V total-normal =V OCV +R battery ×I total ...(9);

[0082] Comparing and subtracting formulas (8) and (9), the voltage difference ΔV2 between the short-circuited battery and the normal battery under the condition of applied charging current can be expressed as:

[0083]

[0084] From formula (10), it can be seen that when the applied current I total The larger the voltage difference ΔV2 between the short-circuited battery and the normal battery, the greater the voltage difference. In other words, similar to the charging state, the pulse current during discharge also has the effect of amplifying this leakage charge reaction.

[0085] Furthermore, as can be seen from formula (10), if an internal short circuit occurs in the battery, the voltage V of the short-circuited battery will be... total It will be lower than the voltage V of a normal battery. total-normal .

[0086] Understandably, if an internal short circuit occurs in the battery, due to leakage current, during the discharge phase, aside from the normal power supply to the load, the leakage current will be reduced. total In addition, there is a portion of current I short The extra heat generated at the short circuit is consumed, resulting in a greater amount of charge required, a faster voltage drop, and a larger rate of change in voltage, i.e., a steeper slope.

[0087] like Figure 5As shown, during the discharge phase, solid line 504 represents the voltage curve of a normal battery, while dashed lines 505 and 506 represent the voltage curves of short-circuit batteries with different short-circuit resistances. The internal resistance of a normal battery tends towards positive infinity and can be expressed as R. short →∞, the short-circuit resistance of the short-circuit battery corresponding to dashed line 506 is less than the short-circuit resistance of the short-circuit battery corresponding to dashed line 505.

[0088] During the discharge phase, the voltage of the short-circuited battery is lower than that of the normal battery. That is, the voltage curve of the short-circuited battery is below that of the normal battery. The more severe the short circuit, the lower the voltage of the short-circuited battery, that is, the lower the voltage curve is. This is manifested as a steeper slope of the voltage curve. The short circuit of the battery corresponding to dashed line 506 is more severe than that of the battery corresponding to dashed line 505.

[0089] In summary, when the same pulse current is applied to both normal and short-circuit batteries during the charging or discharging phases, the short-circuit resistance and voltage change rate differ between the two batteries. Therefore, it is possible to pre-determine the first target voltage change rate of the normal battery under different preset scenarios with different states of charge, temperatures, and charge / discharge rates, and the second target voltage change rate of the short-circuit battery with different short-circuit resistances under different second loading parameters corresponding to different preset scenarios. This allows for the creation of a database capable of detecting early internal short-circuit resistance. Figure 6 As shown, 601, 602, and 603 can be three different preset scenarios. The second loading parameter can include current intensity and current loading time. Each preset scenario corresponds to a different current intensity and current loading time. The current intensities corresponding to the three preset scenarios are 0.3C, 0.5C, and 1C, respectively. The current loading times corresponding to the three preset scenarios are 0 to 15000 seconds, 0 to 8000 seconds, and 0 to 3000 seconds, respectively. Different preset scenarios correspond to different first target change rates of normal battery voltage and second change rates of short-circuit battery voltage with different short-circuit resistances.

[0090] When using the battery under test normally, users can periodically perform pulse current detection on the battery under test. By comparing the first rate of change of the battery under test actually detected with the first target rate of change corresponding to the target scenario, it can be determined whether the battery under test has hidden failure risk (i.e., soft short circuit).

[0091] In this embodiment, by pre-determining the second loading parameter under different preset scenarios, the second pulse current of the second loading parameter is applied to the short-circuit resistance of a normal battery and multiple different short-circuit resistances, respectively. This allows for comparison between the actual detected battery under test and the first target change rate under the target scenario corresponding to the first scenario. This enables a more timely, accurate, and efficient determination of whether the battery under test has experienced a soft short circuit, as well as the degree of the soft short circuit. Consequently, users can be alerted earlier, safety hazards can be eliminated, and the quality of portable terminal products can be improved.

[0092] In some embodiments, the first target rate of change corresponding to the target scenario includes a first target rate of change for charging at the corresponding charging state and a first target rate of change for discharging at the corresponding discharging state; step S1062, "comparing the first rate of change with the first target rate of change corresponding to the target scenario to determine whether the battery under test has an internal short circuit", may include step S10621 or step S10622:

[0093] Step S10621: If the first rate of change is less than the first target rate of change of charge, determine that the battery under test has an internal short circuit;

[0094] Among them, such as Figure 5 As shown, in the charging state, the more severe the short circuit, the flatter the voltage curve. By comparing the first rate of change of the battery under test in the first scenario with the first target charging rate of change of the normal battery in the target scenario, if the first rate of change is less than the first target charging rate of change, it can be said that the battery under test has an internal short circuit. If the first rate of change is greater than or equal to the first target charging rate of change, it can be said that the battery under test has not had an internal short circuit.

[0095] Step S10622: If the first rate of change is greater than the first target discharge rate of change, determine that the battery under test has an internal short circuit.

[0096] like Figure 5 As shown, in the discharge state, the more severe the short circuit, the steeper the voltage curve. By comparing the first rate of change of the battery under test in the first scenario with the first target discharge rate of change of the normal battery in the target scenario, if the first rate of change is greater than the first target discharge rate of change, it can be said that the battery under test has an internal short circuit. If the first rate of change is less than or equal to the first target discharge rate of change, it can be said that the battery under test has not had an internal short circuit.

[0097] In this embodiment, since the voltage change rate of the short-circuited battery and the normal battery have different trends with the degree of short circuit in the charging state and the discharging state, the first change rate is compared with the first target charging change rate of the normal battery in the charging state, and the first change rate is compared with the first target discharging change rate of the normal battery in the discharging state. This allows for a more timely, accurate, and efficient determination of whether the battery under test has an internal short circuit.

[0098] In some embodiments, the first scenario is associated with the state of charge of the battery under test, and the method further includes:

[0099] Step S1031: In the charging state, when it is determined that the state of charge of the battery under test is greater than the first threshold, the step of applying the current is executed;

[0100] Wherein, the first threshold can be between 90% and 100%, such as Figure 5 As shown, during charging, the larger the state of charge, the more significant the difference in the rate of change between a normal battery and a short-circuited battery.

[0101] Step S1032: In the discharge state, when it is determined that the state of charge of the battery under test is less than the second threshold, the step of applying the current is executed; wherein the first threshold is greater than the second threshold.

[0102] The second threshold can be between 0% and 10%, such as... Figure 5 As shown, under discharge conditions, the larger the state of charge, the more significant the difference in the rate of change between normal and short-circuit batteries.

[0103] In this embodiment, since the larger the state of charge in the charging state, the more obvious the difference in the rate of change between the normal battery and the short-circuited battery, and the smaller the state of charge in the discharging state, the more obvious the difference in the rate of change between the normal battery and the short-circuited battery, the step of applying the first pulse current can be performed when the state of charge is large in the charging state and when the state of charge is small in the discharging state, so that the detection of the battery under test can be performed more timely, efficiently and accurately.

[0104] In some embodiments, when it is determined that the battery under test has an internal short circuit, the method further includes: reducing the operating voltage range and reducing the current intensity; alerting the user to the abnormality of the battery under test on the user interface; and increasing the frequency of applying the first pulse current to the battery under test (i.e., increasing the detection frequency of the battery under test).

[0105] In this embodiment of the application, by means of reducing voltage and current, reminding users, and increasing detection frequency, early detection of internal short circuits can be achieved to warn users and thus avoid catastrophic events.

[0106] In some embodiments, the first scenario is associated with the temperature of the battery under test, and the method further includes:

[0107] Step S108: If it is determined that the battery under test has an internal short circuit, determine the corresponding short-circuit resistance based on the first rate of change.

[0108] In this scenario, the target scenario corresponds to multiple short-circuit batteries with different short-circuit resistances. Each short-circuit battery has a different second rate of change. A second target rate of change corresponding to the first rate of change can be determined. The similarity between the second target rate of change and the first rate of change is greater than a preset threshold. Figure 5 As shown, since different short-circuit resistances correspond to different second target change rates, the short-circuit resistance of the second target change rate corresponding to the first change rate can be determined as the short-circuit resistance of the first change rate, that is, the short-circuit resistance of the battery under test.

[0109] Step S110: Obtain the resistance threshold at the temperature corresponding to the first scenario;

[0110] The resistance threshold can be a resistance value that prevents charging during the charging state or a resistance value that prevents discharging during the discharging state; the resistance value that prevents charging and the resistance value that prevents discharging can be the same or different.

[0111] Step S112: If the short-circuit resistance is less than the resistance threshold, charging or discharging the battery under test is prohibited.

[0112] In this embodiment of the application, if the short-circuit resistance is less than the resistance threshold, it indicates that the short circuit of the battery under test is severe and there is a serious risk of hidden failure. In this case, charging or discharging the battery under test can be prohibited to avoid catastrophic events.

[0113] This application provides a method for diagnosing whether a battery has an internal short circuit using a pulse current probe. This method can sensitively and accurately detect short circuits in the early stage (soft short circuit stage). By estimating the short circuit resistance and leakage charge level, it can inform the user of the true state of the battery and enable timely preventive measures.

[0114] In this embodiment, leakage current generated by an internal short circuit occupies the battery's charge / discharge capacity, and this leaked charge accumulates throughout the charge / discharge cycle, making the aged battery stand in stark contrast to a new battery. When a pulsed current is used to push it to its limit, the effect of the leakage current is amplified. By performing a pulsed current limit test on the battery under different discharge / charge states, the resistance of the soft short-circuit simulation circuit can be estimated, thereby determining the internal short circuit condition of the battery.

[0115] like Figure 7 As shown, the detection logic flow of the battery under test may include the following steps:

[0116] Step S701: Battery modeling;

[0117] This allows us to obtain battery charging and discharging characteristic parameters, such as voltage, current, temperature, and capacity; and determine the magnitude of the pulse loading current.

[0118] Step S702: Pulse current loading;

[0119] Among them, it can test the rate of change of voltage over time of normal batteries under different charge / discharge rates, different states of charge, and different temperatures, as well as the rate of change of voltage over time of batteries with different short-circuit resistances under the corresponding conditions, and establish a database under different charge / discharge rates, different states of charge, and different temperatures; and update the battery charge / discharge characteristic parameters based on the data in the database.

[0120] In practical applications, consider batteries with varying degrees of internal short circuit and aging, meaning different short-circuit resistance values; different initial states of charge (SOC), ranging from 100% to 0%. During charging tests, the SOC can be set between 90% and 100%, while during discharging tests, it can be set between 0% and 10%. In these cases, the slopes of the voltage curves for normal and short-circuited batteries differ significantly. Short-circuit resistance values ​​change under different temperature conditions; specified loading currents can vary, such as 0.1C, 0.3C, 0.5C, 1C, and 2C; specified loading current durations can differ, such as 1s, 10s, and 1min; and specified cutoff voltages can differ, such as 4.2V, 4.3V, and 4.4V during charging, and 3.4V, 3.2V, and 3.0V during discharging. These combinations can form different preset scenarios and create a database.

[0121] Step S703: Determine if an internal short circuit has occurred in the battery;

[0122] Specifically, the voltage change rate of the tested battery over time can be compared with the voltage change rate of a battery under normal conditions (i.e., a normal battery) in the database to determine whether the tested battery has an internal short circuit. If the tested battery has an internal short circuit, a voltage reduction and current limiting process is performed, and the user is warned that the tested battery is abnormal.

[0123] It should be noted that, in the embodiments of this application, if the above-described battery detection method is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiments of this application, or the part that contributes to the related technology, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause an electronic device (which may be a mobile phone, tablet computer, desktop computer, personal digital assistant, navigator, digital phone, video phone, television, sensor device, etc.) to execute all or part of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, mobile hard drives, read-only memory (ROM), magnetic disks, or optical disks. Thus, the embodiments of this application are not limited to any specific hardware and software combination.

[0124] Figure 8 This is a schematic diagram of the composition structure of a battery detection device according to an embodiment of this application, as shown below. Figure 8 As shown, the device 800 includes: a first determining module 801, a first loading module 802, and an analysis module 803, wherein:

[0125] The first determining module 801 is used to determine the first loading parameters of the first pulse current;

[0126] The first loading module 802 is used to apply the first pulse current to the battery under test based on the first loading parameters to obtain the first rate of change of the voltage of the battery under test;

[0127] The analysis module 803 is used to determine whether the battery under test has an internal short circuit based on the first rate of change.

[0128] In some embodiments, the apparatus further includes: a second determining module for determining a first scenario in which the battery under test is located; and a third determining module for determining the first loading parameter of the first pulse current based on the first scenario; wherein: the first scenario is associated with at least one of the following parameters: the state of charge of the battery under test; the charge / discharge rate of the battery under test; and the temperature of the battery under test.

[0129] In some embodiments, the third determining module includes: a first determining submodule, configured to determine the current intensity and current loading time of the first pulse current, or the current intensity and the cutoff voltage of the battery under test, based on the first scenario; correspondingly, the first loading module 802 includes: a first obtaining submodule, configured to obtain a first rate of change of voltage of the battery under test based on the current intensity and the current loading time; or, a second obtaining submodule, configured to obtain a first rate of change of voltage of the battery under test based on the current intensity and the cutoff voltage of the battery under test.

[0130] In some embodiments, the analysis module 803 includes: a third determining submodule, configured to determine a target scenario corresponding to the first scenario; and a comparison submodule, configured to compare the first rate of change with a first target rate of change corresponding to the target scenario to determine whether the battery under test has an internal short circuit, wherein the target scenario is a preset scenario in a standard database.

[0131] In some embodiments, the apparatus further includes: a fourth determining module for determining a plurality of different preset scenarios; a fifth determining module for determining a second loading parameter of the second pulse current based on each preset scenario; a second loading module for loading the second pulse current onto a normal battery based on the second loading parameter to obtain a first target rate of change of the voltage of the normal battery; the normal battery being a battery that has not experienced an internal short circuit; a third loading module for loading the second pulse current onto a plurality of different short-circuited batteries based on the second loading parameter to obtain a second target rate of change of the voltage of each short-circuited battery; the short-circuited battery being a battery that has experienced an internal short circuit; different short-circuited batteries have different short-circuit resistances; wherein: the preset scenario in which the normal battery / the short-circuited battery is located is associated with at least one of the following parameters: the state of charge of the normal battery / the short-circuited battery; the charge / discharge rate of the normal battery / the short-circuited battery; the temperature of the normal battery / the short-circuited battery.

[0132] In some embodiments, the first target rate of change corresponding to the target scenario includes a first target rate of change of charge when the target charging state is corresponding to a first target rate of change of charge and a first target rate of change of discharge when the target discharging state is corresponding to a first target rate of change of charge; the comparison submodule includes: a first determining unit, configured to determine that the battery under test has an internal short circuit when the first rate of change of charge is less than the first target rate of change of charge; or, a second determining unit, configured to determine that the battery under test has an internal short circuit when the first rate of change of charge is greater than the first target rate of change of discharge.

[0133] In some embodiments, wherein the first scenario is associated with the state of charge of the battery under test, the device further includes: a sixth determining module, configured to perform the step of applying the loading current when the state of charge of the battery under test is determined to be greater than a first threshold during charging; and a seventh determining module, configured to perform the step of applying the loading current when the state of charge of the battery under test is determined to be less than a second threshold during discharging; wherein the first threshold is greater than the second threshold.

[0134] In some embodiments, the first scenario is associated with the temperature of the battery under test, and the device further includes: an eighth determining module, configured to determine a corresponding short-circuit resistance based on the first rate of change when it is determined that the battery under test has an internal short circuit; an acquiring module, configured to acquire a resistance threshold at the temperature corresponding to the first scenario; and a prohibiting module, configured to prohibit charging or discharging the battery under test when the short-circuit resistance is less than the resistance threshold.

[0135] Correspondingly, embodiments of this application provide an electronic device, Figure 9 This is a schematic diagram of a hardware entity of an electronic device according to an embodiment of this application, such as... Figure 9 As shown, the hardware entity of the electronic device 900 includes a memory 901 and a processor 902. The memory 901 stores a computer program that can run on the processor 902. When the processor 902 executes the program, it implements the steps in the battery detection method of the above embodiment.

[0136] The memory 901 is configured to store instructions and applications executable by the processor 902, and can also cache data to be processed or already processed by the processor 902 and the various modules in the device 900 (e.g., image data, audio data, voice communication data and video communication data), which can be implemented by flash memory or random access memory (RAM).

[0137] Correspondingly, embodiments of this application provide a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps in the battery detection method provided in the above embodiments.

[0138] It should be noted that the descriptions of the storage medium and device embodiments above are similar to those of the method embodiments above, and have similar beneficial effects as the device embodiments. For technical details not disclosed in the storage medium and method embodiments of this application, please refer to the descriptions of the device embodiments of this application for understanding.

[0139] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of this application. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It should be understood that in the various embodiments of this application, the sequence numbers of the above-described processes do not imply a sequential order of execution; the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application. The sequence numbers of the above-described embodiments are merely descriptive and do not represent the superiority or inferiority of the embodiments.

[0140] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0141] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods, such as: multiple units or components can be combined, or integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the various components shown or discussed can be through some interfaces, and the indirect coupling or communication connection between devices or units can be electrical, mechanical, or other forms.

[0142] The units described above as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; they may be located in one place or distributed across multiple network units; some or all of the units may be selected to achieve the purpose of this embodiment according to actual needs. Furthermore, the functional units in the embodiments of this application may all be integrated into one processing unit, or each unit may be a separate unit, or two or more units may be integrated into one unit; the integrated unit may be implemented in hardware or in a combination of hardware and software functional units.

[0143] Those skilled in the art will understand that all or part of the steps of the above method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it performs the steps of the above method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as mobile storage devices, read-only memory (ROM), magnetic disks, or optical disks. Alternatively, if the integrated units of this application are implemented as software functional modules and sold or used as independent products, they can also be stored in a computer-readable storage medium. Based on this understanding, the technical solutions of the embodiments of this application, or the parts that contribute to the related technology, can be embodied in the form of software products. These computer software products are stored in a storage medium and include several instructions to cause computer devices (which may be mobile phones, tablets, desktops, personal digital assistants, navigators, digital phones, video phones, televisions, sensing devices, etc.) to execute all or part of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as mobile storage devices, ROMs, magnetic disks, or optical disks.

[0144] The methods disclosed in the several method embodiments provided in this application can be arbitrarily combined to obtain new method embodiments without conflict. The features disclosed in the several product embodiments provided in this application can be arbitrarily combined to obtain new product embodiments without conflict. The features disclosed in the several method or device embodiments provided in this application can be arbitrarily combined to obtain new method embodiments or device embodiments without conflict.

[0145] The above description is merely an embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A battery detection method, the method comprising: Determine the primary scenario in which the battery under test is located; The first loading parameter is determined based on the first scenario; wherein, the first pulse current corresponding to the first loading parameter is a pulse current that amplifies the leakage charge effect to the limit for batteries of the same type as the battery under test in the first scenario without current overload. Based on the first loading parameters, the first pulse current is applied to the battery under test, and the first rate of change of the voltage of the battery under test is obtained. Based on the first rate of change, it is determined whether the battery under test has experienced an internal short circuit.

2. The method according to claim 1, wherein, The first scenario is associated with at least one of the following parameters: The state of charge of the battery under test; The charge / discharge rate of the battery under test; The temperature of the battery to be tested.

3. The method according to claim 1 or 2, wherein, The first loading parameter for determining the first pulse current based on the first scenario includes: Based on the first scenario, determine the current intensity and current loading time of the first pulse current, or the current intensity and the cutoff voltage of the battery under test; Correspondingly, the step of applying the first pulse current to the battery under test based on the first loading parameters to obtain the first rate of change of the voltage of the battery under test includes: The first rate of change of the voltage of the battery under test is obtained based on the current intensity and the current loading time; or the first rate of change of the voltage of the battery under test is obtained based on the current intensity and the cutoff voltage of the battery under test.

4. The method according to claim 1 or 2, wherein, The step of determining whether the battery under test has an internal short circuit based on the first rate of change includes: Determine the target scene corresponding to the first scene; The first rate of change is compared with the first target rate of change corresponding to the target scenario to determine whether the battery under test has an internal short circuit, wherein the target scenario is a preset scenario in a standard database.

5. The method according to claim 4, further comprising: Define multiple different preset scenarios; The second loading parameter of the second pulse current is determined based on each of the preset scenarios; Based on the second loading parameters, the second pulse current is applied to the normal battery to obtain the first target rate of change of the voltage of the normal battery; The normal battery is a battery that has not experienced an internal short circuit; Based on the second loading parameters, the second pulse current is applied to multiple different short-circuited batteries to obtain a second target rate of change of voltage for each short-circuited battery; the short-circuited battery is a battery that has experienced an internal short circuit; different short-circuited batteries have different short-circuit resistances; Wherein: the preset scenario in which the normal battery / short-circuit battery is located is associated with at least one of the following parameters: the state of charge of the normal battery / short-circuit battery; the charge / discharge rate of the normal battery / short-circuit battery; and the temperature of the normal battery / short-circuit battery.

6. The method according to claim 4, wherein, The first target change rate corresponding to the target scenario includes the first target charging change rate when the corresponding charging state is present and the first target discharging change rate when the corresponding discharging state is present. The step of comparing the first rate of change with the first target rate of change corresponding to the target scenario to determine whether the battery under test has an internal short circuit includes: If the first rate of change is less than the first target rate of charge change, it is determined that the battery under test has an internal short circuit. or, If the first rate of change is greater than the first target discharge rate of change, it is determined that the battery under test has an internal short circuit.

7. The method according to claim 1 or 2, further comprising: in, The first scenario is associated with the state of charge of the battery under test. When the state of charge of the battery under test is determined to be greater than the first threshold during charging, the step of applying the current is executed. When the state of charge of the battery under test is determined to be less than the second threshold during the discharge state, the step of applying the current is executed. The first threshold is greater than the second threshold.

8. The method according to claim 1 or 2, wherein, The first scenario is related to the temperature of the battery under test, and the method further includes: If it is determined that the battery under test has an internal short circuit, the corresponding short-circuit resistance is determined based on the first rate of change. Obtain the resistance threshold at the temperature corresponding to the first scenario; Charging or discharging the battery under test is prohibited if the short-circuit resistance is less than the resistance threshold.

9. A battery testing device, the device comprising: The first determination module is used to determine the first scenario in which the battery under test is located. The first loading parameter is determined based on the first scenario; wherein, the first pulse current corresponding to the first loading parameter is a pulse current that amplifies the leakage charge effect to the limit for batteries of the same type as the battery under test in the first scenario without current overload. The first loading module is used to apply the first pulse current to the battery under test based on the first loading parameters, and obtain the first rate of change of the voltage of the battery under test. An analysis module is used to determine whether the battery under test has experienced an internal short circuit based on the first rate of change.

10. An electronic device comprising a memory and a processor, the memory storing a computer program executable on the processor, characterized in that, When the processor executes the program, it implements the steps of the battery detection method according to any one of claims 1 to 8.

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