Battery life detection circuit, detection method, and electrical device

Abstract

The application relates to the technical field of batteries, in particular to a battery life detection circuit, a detection method and an electric device. The battery life is determined by calculating the actual internal resistance of the battery, so that the aging determination can be directly based on the real internal resistance of the battery, and the accuracy of the battery life detection is improved. According to the application, a plurality of detection branches are arranged, the internal resistance can be solved through a plurality of groups of voltage sampling, an additional high-precision current sampling device is not needed, and the internal resistance of the battery can be accurately calculated only by relying on voltage sampling, so that the hardware cost can be reduced to a certain extent, and the circuit structure is simplified. Meanwhile, the battery life is determined according to different states of the battery, so that the single threshold can be prevented from being misjudged under different working conditions, and the reliability of the life determination is improved. Further, the application further arranges a load switch, the rear-end load can be disconnected when the internal resistance is detected, so that the interference of the load current on the internal resistance sampling can be eliminated, and the measurement error caused by the load access can be avoided.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to a battery life detection circuit, detection method, and electrical device. Background Technology

[0002] Currently, battery-powered appliances are widely used. Batteries experience capacity degradation after multiple charge-discharge cycles, and severe degradation necessitates timely replacement. However, individual batteries vary, and user charging habits and actual equipment loads differ, resulting in inconsistent battery degradation patterns. Existing solutions often rely on the number of charge-discharge cycles to estimate battery life, but this estimation is prone to error due to the aforementioned factors, making it difficult for users to accurately determine the remaining battery life and the appropriate time for replacement. Summary of the Invention

[0003] In view of this, this application provides a battery life detection circuit and power device to solve the technical problem in the prior art that the remaining life of a battery cannot be accurately determined.

[0004] In a first aspect, this application provides a battery life detection circuit, the detection circuit comprising: Battery; A load switch, one end of which is connected to one end of the battery, and the other end of which is connected to the load; the other end of the load switch and the other end of the battery are used together to supply power to the load. The detection component includes at least two detection branches, each connected in parallel to both ends of the battery; each detection branch includes a detection switch and a detection resistor connected in series, and when the detection switch is turned on, the corresponding detection branch and the battery form a detection circuit. The control component has a sampling and detection terminal, which is connected between the detection switch and the detection resistor of the corresponding detection branch. The sampling and detection terminal is used to collect the detection voltage across the detection resistor and obtain the actual internal resistance of the battery. The control component is electrically connected to the load switch and the detection switch of each detection branch, respectively, and is used to control the on / off state of the load switch and each detection switch. If the battery is fully charged and not in operation, and the actual internal resistance is greater than the first threshold, then the battery's lifespan has expired. If the battery is in operation and its actual internal resistance is greater than the second threshold, then the battery has reached the end of its lifespan.

[0005] Beneficial Effects: Since battery life is related to the battery's actual internal resistance, this solution determines battery life by calculating the actual internal resistance. This eliminates the influence of individual battery differences, user charging habits, and load conditions, directly determining aging based on the battery's true internal resistance, thus improving the accuracy of battery life detection. Furthermore, this solution uses multiple detection branches, allowing for internal resistance calculation through multiple sets of voltage sampling. It eliminates the need for additional high-precision current sampling devices, accurately calculating the battery's internal resistance solely through voltage sampling, which can reduce hardware costs and simplify the circuit structure to some extent. Simultaneously, this solution judges lifespan based on different battery states, avoiding misjudgments due to a single threshold under different operating conditions, thus improving the reliability of lifespan determination. Further, this solution includes a load switch, which disconnects the downstream load during internal resistance detection, eliminating interference from load current on internal resistance sampling and avoiding measurement errors caused by load connection.

[0006] In one optional implementation, the detection component includes a first detection branch and a second detection branch; The first detection branch includes a first detection switch and a first detection resistor, and the second detection branch includes a second detection switch and a second detection resistor.

[0007] Beneficial effects: This embodiment uses two detection branches to complete two sets of voltage sampling, which is sufficient to complete the battery internal resistance calculation. This avoids the inability to perform internal resistance calculation with a single detection branch, and also avoids excessive circuit components and complex circuit structure due to too many detection branches. It is suitable for integration into small household appliances and other electrical appliances.

[0008] In one optional implementation, the battery voltage is E, and the actual internal resistance is r; the detection voltage collected by the sampling and detection terminal in the first detection branch is A, and the detection voltage collected in the second detection branch is B; the current flowing through the first detection branch is I1, and the current flowing through the second detection branch is I2; the resistance of the first detection resistor is T1, and the resistance of the second detection resistor is T2. The control components are configured to calculate the actual internal resistance r of the battery based on the following relationship: Equation 1: E=I1 r+A;A=I1 T1; Equation 2: E=I2 r+B;B=I2 T2; Formula 3: r=(BA) / (A / T1-B / T2).

[0009] Beneficial effects: This embodiment uses the voltage values ​​collected by two sets of detection branches and the known resistance value of the detection resistor. Therefore, the actual internal resistance of the battery can be directly calculated through this set of relationships. There is no need to add additional current sampling and battery voltage sampling components. All signal acquisition and calculation can be completed using the voltage sampling port of the control component. The actual battery internal resistance value can also be obtained, improving the accuracy of battery internal resistance calculation.

[0010] In one alternative implementation, the battery has an initial internal resistance, and the control component is preset with a first threshold and a second threshold; the first threshold is 3 times the initial internal resistance, and the second threshold is 2 times the initial internal resistance.

[0011] Beneficial effects: Since the internal resistance of a battery follows a U-shaped trend with its charge level (maximum resistance when fully charged and empty, minimum resistance between 30% and 60% charge, which is also the range where the battery operates for the longest time), this embodiment sets a higher first threshold and a lower second threshold. Furthermore, this embodiment sets thresholds based on the differences in the electrochemical characteristics of the batteries themselves, avoiding the use of a single threshold and further improving the accuracy of battery life assessment.

[0012] In one optional implementation, when the battery is fully charged and not in operation, the control component is configured to perform multiple internal resistance tests on the battery within a first preset duration, with each test lasting for the first detection duration.

[0013] Beneficial effects: This embodiment performs multiple tests within a first preset time period while the battery is fully charged and not in operation. This filters out transient interference in the circuit and avoids accidental measurement deviations during voltage sampling, thus preventing misjudgments of battery life caused by single sampling anomalies. Furthermore, when the battery is tested in the device's standby or power-off state, the sampling environment is relatively stable because the load is not running, making it suitable for obtaining the battery's true internal resistance data.

[0014] In one optional implementation, when the actual internal resistance detected when the battery is in a fully charged but not working state is greater than a first threshold, the control component obtains the actual internal resistance of the battery again after the battery has been left to stand for a second preset period of time.

[0015] Beneficial effects: When the battery is first fast charged, it is in a state of electrochemical imbalance, and the measured internal resistance is too high, which is not the actual internal resistance of the battery. Therefore, this solution will not directly assume that the battery has reached the end of its life after detecting that the internal resistance exceeds the standard. Instead, it will test the battery after it has been left to stand for a period of time and the polarization of the battery has been eliminated. This can effectively avoid the problem of the battery not aging but being wrongly judged to have reached the end of its life, and improve the accuracy of the measurement.

[0016] In one optional implementation, the first preset duration is 1 minute, and the second preset duration is between 10 minutes and 30 minutes.

[0017] Beneficial effects: In this embodiment, the first preset time is set to 1 minute. This allows for multiple measurements of the battery's internal resistance within a short period, avoiding excessively long time spans that could lead to data inaccuracies. Furthermore, this embodiment sets the resting time between 10 and 30 minutes. This time range is sufficient to eliminate the polarization effect after lithium battery charging, while avoiding wasted time due to excessive resting time. This balances measurement reliability and efficiency.

[0018] In one optional implementation, when the battery is in operation, the control component is configured to perform multiple internal resistance detections every third preset time interval to obtain multiple sets of internal resistance detection values, and take the average value of the multiple sets of internal resistance detection values ​​as the actual internal resistance of the battery.

[0019] Beneficial effects: When the battery is in a working discharge state, a dynamic electrochemical process occurs inside the battery, which can cause significant fluctuations in the measured internal resistance. Therefore, this embodiment obtains multiple sets of internal resistance values ​​through multiple rounds of testing, and then averages these values. This effectively suppresses the influence of dynamic changes during discharge, resulting in a battery internal resistance that more closely approximates the actual state and improves measurement accuracy.

[0020] In one alternative implementation, the third preset duration is 2 minutes.

[0021] Beneficial effects: In this embodiment, the third preset duration is set to 2 minutes. This time period can not only detect the change process of battery internal resistance in time, but also reduce the number of sampling and calculations of the control component, which can reduce the power consumption of the control component to a certain extent.

[0022] Secondly, this application provides a method for detecting battery life, applied to the detection circuit described in any of the above embodiments, the method comprising: S1. When testing battery life, disconnect the load switch to cut off the power supply to the load; S2. Sequentially turn on each detection branch and collect the detection voltage corresponding to the detection resistor in each detection branch through the sampling detection terminal of the control component; S3. Calculate the actual internal resistance of the battery based on each detection voltage and the corresponding detection resistor value; S4. Obtain the battery's operating status and charge status; if the battery is fully charged and not in operation, and the actual internal resistance is greater than the first threshold, then the battery life is determined to have expired; if the battery is in operation, and the actual internal resistance is greater than the second threshold, then the battery life is determined to have expired.

[0023] Thirdly, this application provides an electrical device comprising: a load and a battery life detection circuit as described in any of the above embodiments.

[0024] Beneficial effects: This solution integrates the battery life detection circuit into the electrical device, enabling devices with batteries to have built-in self-diagnosis capabilities for battery aging, eliminating the need for external testing instruments. Since the device can autonomously identify the battery's aging status, it solves the problem of users not knowing the remaining battery life or knowing when to replace it, thus improving the product's intelligence and user experience.

[0025] In one optional embodiment, the electrical device further includes: The prompt component communicates with the control component of the detection circuit. When the control component determines that the battery life has expired, it drives the prompt component to output a prompt message.

[0026] Beneficial effects: After the battery life expires, the control component drives the prompt component to output a prompt message, thereby proactively informing the user of the battery aging status and reminding the user to replace the battery in time. This avoids the problem of drastically reduced battery life and unstable power supply when the battery is severely aged, thus improving the user experience. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the battery life detection circuit in an embodiment of this application.

[0029] Explanation of reference numerals in the attached figures: 10. Battery; 20. Load switch; 30. Load; 40. Detection component; 41. First detection branch; 411. First detection switch; 412. First detection resistor; 42. Second detection branch; 421. Second detection switch; 422. Second detection resistor; 50. Control components; 60. Prompt component. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0031] In the description of this application, it should be noted that the terms "inner," "upper," "outer," "lower," "underneath," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0032] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "communication" should be interpreted broadly. For example, they can refer to fixed communication, detachable communication, or integral communication; they can refer to mechanical communication or electrical communication; they can refer to direct connection or indirect connection through an intermediate medium; they can refer to communication within two components; and they can refer to wireless communication or wired communication. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0033] With the widespread use of battery-powered electrical appliances, many products on the market now utilize batteries, especially rechargeable batteries. However, the capacity of a rechargeable battery, also known as its lifespan, gradually decreases with each charging cycle. Different batteries have different capacities and rates of degradation. Furthermore, user charging habits and the actual load on devices vary, resulting in an inconsistent degradation pattern. This leads to inconsistent capacity decay, leaving users unaware of the battery's actual remaining lifespan and thus unsure when to replace it.

[0034] Currently, the remaining lifespan of the battery is typically calculated based on the number of charges. Once the cumulative number of charges reaches the total, the user is prompted to replace the battery. For example, if the battery can only be charged 100 times, and it's charged every two days, then the user will be prompted to replace the battery after 200 days. However, each user's charging habits are different; they might charge at 80%, 50%, or 30%, which means the number of charges doesn't accurately reflect the remaining lifespan of the battery.

[0035] For example, two lithium batteries from the same batch, both rated for 500 cycles, showed noticeable aging after only 400 cycles if one was used until it reached 20% before being fully charged. The other was frequently charged as needed, maintaining a charge level of 50%. With 80% charge, the battery still performs well after 600 charges. Traditional solutions only count the number of charges, and if both batteries are scheduled for replacement at 500 charges each, one battery will prompt a replacement too late, while the other will prompt a replacement too early.

[0036] Therefore, this solution starts with the internal resistance of battery 10, calculating its actual internal resistance in real time using a circuit. Then, the magnitude of the internal resistance is used to determine whether battery 10 is aging. The following section combines... Figure 1 This describes an embodiment of the present application.

[0037] like Figure 1 As shown, according to an embodiment of this application, in one aspect, this application provides a detection circuit for the life of a battery 10, the detection circuit including a battery 10, a load switch 20, a detection branch and a control component 50.

[0038] Specifically, in this embodiment, battery 10 is a rechargeable battery 10, such as a lead-acid battery 10 or a lithium battery 10. Of course, battery 10 can also be a dry cell battery 10. This embodiment is merely an example of a specific type of battery 10, but it does not limit the scope of the embodiment. Those skilled in the art can make changes according to the actual situation, as long as the same technical effect is achieved.

[0039] Furthermore, in this embodiment, one end of the load switch 20 is connected to one end of the battery 10, and the other end of the load switch 20 is connected to the load 30. The other end of the load switch 20 and the other end of the battery 10 are used together to supply power to the load 30. Therefore, when one end of the load switch 20 is connected to the positive terminal of the battery 10, the other end of the load switch 20 is connected to the positive terminal of the load 30, and the other end of the battery 10 is the negative terminal and is connected to the corresponding negative terminal of the load 30. Similarly, when one end of the load switch 20 is connected to the negative terminal of the battery 10, the other end of the load switch 20 is connected to the negative terminal of the load 30, and the other end of the battery 10 is the positive terminal and is connected to the corresponding positive terminal of the load 30.

[0040] The load switch 20 can be a mechanical switch or an electromagnetic switch, such as a relay. Of course, this embodiment is merely an example of the type of load switch 20, and does not limit its application. Those skilled in the art can modify it according to actual circumstances, as long as the same technical effect is achieved.

[0041] In one specific embodiment, the load switch 20 can be an electromagnetic relay, and the relay coil is driven by the control component 50. When performing internal resistance detection, the control component 50 outputs a level to open the relay and cut off the power supply to the load 30. After all the detections are completed, the relay is controlled to close again to restore the normal power supply to the load 30.

[0042] When testing the actual internal resistance of battery 10, the load switch 20 needs to be disconnected. This disconnects the load 30 from the circuit, thereby eliminating the interference of the load 30 current on the internal resistance sampling and avoiding measurement errors caused by the connection of the load 30.

[0043] Furthermore, in this embodiment, the detection component 40 is provided with at least two detection branches. For example, it can have two, three, four, five, six, etc. Of course, this embodiment is merely an example of the number of detection branches, but it is not a limitation. Those skilled in the art can change it according to the actual situation, as long as the same technical effect is achieved.

[0044] Furthermore, in this embodiment, each detection branch is connected in parallel across the two ends of the battery 10. That is, one end of the detection branch is connected to the negative terminal of the battery 10, and the other end of the detection branch is connected to the positive terminal of the battery 10. Furthermore, each detection branch includes a detection switch and a detection resistor connected in series. When the detection switch is turned on, the corresponding detection branch and the battery 10 form a detection circuit. This embodiment uses the example of connecting the other end of the detection switch to the positive terminal of the battery 10 and the other end of the detection resistor to the negative terminal of the battery 10 for illustration.

[0045] The detection switch can be a mechanical switch or an electromagnetic switch, such as a relay. It can also be a switching transistor, such as a MOSFET or a triode. This embodiment is merely an example of the types of detection switches and is not intended to limit the scope. Those skilled in the art can modify it according to actual circumstances, as long as the same technical effect is achieved.

[0046] In the preferred embodiment corresponding to the attached drawings, the first detection switch 411 and the second detection switch 421 are NPN transistors, with their bases connected to different I / O ports of the control component 50. When the control component 50 outputs a high level, the transistors conduct, and the corresponding detection branch is connected; when the output is low, the transistors are cut off, and the detection branch is disconnected. The two detection branches do not conduct simultaneously, but are selected in a time-division manner. Furthermore, the first detection resistor 412 and the second detection resistor 422 can be fixed power resistors with good precision, and their resistance values ​​are matched according to the voltage of the battery 10 to prevent excessive branch current.

[0047] Furthermore, in this embodiment, the control component 50 has a sampling detection terminal, which is connected between the detection switch and the detection resistor of the corresponding detection branch. The sampling detection terminal is used to collect the detection voltage across the detection resistor and obtain the actual internal resistance of the battery 10. The control component 50 is electrically connected to the load switch 20 and the detection switches of each detection branch, respectively, and is used to control the on / off state of the load switch 20 and each detection switch.

[0048] Specifically, when the detection switch is turned on, current flows through the detection circuit, sequentially passing through the positive terminal of battery 10, the detection switch, the detection resistor, and the negative terminal of battery 10. Therefore, in the detection circuit, the internal resistance of battery 10 shares a portion of the voltage, and the detection resistor shares a portion of the voltage. Thus, the control component 50 can calculate the actual internal resistance of battery 10 by sampling the voltage division of the detection resistor.

[0049] Since the resistance value of the sensing resistor is fixed and the voltage division of the sensing resistor can be detected, only the voltage of battery 10 and the actual internal resistance of battery 10 are unknown. Therefore, the actual internal resistance of battery 10 can be obtained by calculation based on multiple sensing circuits.

[0050] Furthermore, in this embodiment, after calculating the actual internal resistance of the battery 10, it is also necessary to determine whether the battery 10 has reached the end of its lifespan, i.e., whether the battery 10 needs to be replaced, based on the actual internal resistance of the battery 10.

[0051] If battery 10 is fully charged and not in operation, and its actual internal resistance is greater than the first threshold, then battery 10 has reached the end of its lifespan and needs to be replaced; if the actual internal resistance is not greater than the first threshold, it means that battery 10 is in normal lifespan and does not need to be replaced.

[0052] If battery 10 is in operation and its actual internal resistance is greater than the second threshold, then battery 10 has reached the end of its lifespan and needs to be replaced; if the actual internal resistance is not greater than the second threshold, then battery 10 is in normal lifespan and does not need to be replaced.

[0053] This embodiment does not limit the specific values ​​of the first threshold and the second threshold. Those skilled in the art can make changes according to the actual situation, as long as the same technical effect can be achieved.

[0054] Since the lifespan of battery 10 is related to its actual internal resistance, this solution determines its lifespan by calculating the actual internal resistance. This eliminates the influence of individual differences in battery 10, user charging habits, and load 30 operating conditions, directly determining aging based on the battery 10's true internal resistance, thus improving the accuracy of battery 10 lifespan detection. Furthermore, this solution uses multiple detection branches, allowing for internal resistance calculation through multiple voltage samples. It eliminates the need for additional high-precision current sampling devices, accurately calculating the battery 10's internal resistance solely through voltage sampling, thereby reducing hardware costs and simplifying the circuit structure. Simultaneously, this solution judges lifespan based on different states of battery 10, avoiding misjudgments due to a single threshold under different operating conditions, improving the reliability of lifespan determination. Further, this solution includes a load switch 20, which disconnects the downstream load 30 during internal resistance detection, eliminating interference from the load 30's current on internal resistance sampling and avoiding measurement errors caused by the load 30's connection.

[0055] Furthermore, in an optional embodiment, the detection component 40 includes a first detection branch 41 and a second detection branch 42. The first detection branch 41 includes a first detection switch 411 and a first detection resistor 412, and the second detection branch 42 includes a second detection switch 421 and a second detection resistor 422.

[0056] This embodiment uses two detection branches to complete two sets of voltage sampling, which is sufficient to complete the internal resistance calculation of the battery. This avoids the inability to perform internal resistance calculation with a single detection branch, and also avoids excessive circuit components and complex circuit structure due to too many detection branches. It is suitable for integration into small household appliances and other electrical appliances.

[0057] As an alternative embodiment, the detection component 40 can also be configured with three or more detection branches, each with an independent detection switch and detection resistors of different resistance values. During calculation, any two sets of sampled voltages are selected to participate in the internal resistance calculation, and the remaining branches can be used for redundancy verification. When a device malfunctions in a certain branch, other branches can be switched to complete the detection, further improving the circuit's fault resistance performance.

[0058] Further, in an optional embodiment, the voltage of battery 10 is E, and the actual internal resistance is r; the detection voltage collected by the sampling detection terminal in the first detection branch 41 is A, and the detection voltage collected in the second detection branch 42 is B; the current flowing through the first detection branch 41 is I1, and the current flowing through the second detection branch 42 is I2; the resistance value of the first detection resistor 412 is T1, and the resistance value of the second detection resistor 422 is T2. Control component 50 is configured to calculate the actual internal resistance r of battery 10 according to the following relationship: Equation 1: E=I1 r+A;A=I1 T1; Equation 2: E=I2 r+B;B=I2 T2; Therefore, Equation 3 can be obtained from Equations 1 and 2; Formula 3: r=(BA) / (A / T1-B / T2); Finally, the actual internal resistance of battery 10 is calculated using Equation 3.

[0059] In this embodiment, the actual internal resistance of battery 10 can be directly calculated by using the voltage values ​​collected by two sets of detection branches and the known resistance values ​​of the detection resistors. There is no need to add additional current sampling and voltage sampling components for battery 10. All signal acquisition and calculation can be completed using the voltage sampling port of control component 50, and the true internal resistance value of battery 10 can be obtained, thus improving the accuracy of the internal resistance calculation of battery 10.

[0060] Furthermore, in an optional embodiment, the battery 10 has an initial internal resistance, and the control component 50 is preset with a first threshold and a second threshold; the first threshold is 3 times the initial internal resistance, and the second threshold is 2 times the initial internal resistance.

[0061] Since the internal resistance of battery 10 exhibits a U-shaped trend with its charge level—that is, the internal resistance is highest when fully charged and empty, and lowest when the charge level is between 30% and 60%, which is also the region where battery 10 operates for the longest time—this embodiment sets a higher first threshold and a lower second threshold. Furthermore, this embodiment sets thresholds based on the differentiated electrochemical characteristics of battery 10 itself, avoiding the use of a single threshold and further improving the accuracy of battery life assessment.

[0062] As an alternative embodiment, the first threshold and the second threshold can be stored in the memory of the control component 50; different threshold coefficients can be programmed into the device at the factory for different battery models 10 without modifying the hardware circuit. For example, for lead-acid batteries 10, a threshold multiple adapted to lead-acid batteries 10 can be configured, thereby achieving a single set of hardware compatible with multiple battery types 10.

[0063] Furthermore, in an optional embodiment, when the battery 10 is in a fully charged and non-operating state, the control component 50 is configured to perform multiple internal resistance detections on the battery 10 within a first preset duration, with each detection lasting for the first detection duration.

[0064] In this embodiment, the internal resistance of battery 10 can be continuously detected for 2 seconds within one minute. There is no special requirement for this duration; the purpose is to prevent inaccurate detection. Typically, 2 seconds is sufficient to detect the voltage values ​​across the first detection resistor 412 and the second detection resistor 422. If a control component 50 with a faster processing speed is used, 1 second is also sufficient to detect the voltage values ​​across the first detection resistor 412 and the second detection resistor 422.

[0065] In this embodiment, multiple tests are performed within a first preset time period while the battery 10 is fully charged and not in operation. This filters out transient interference in the circuit and avoids accidental measurement deviations during voltage sampling, thus preventing misjudgments of the battery 10's lifespan due to single sampling anomalies. Furthermore, when the battery 10 is tested in the device's standby or power-off state, the sampling environment is relatively stable because the load 30 is not running, making it suitable for obtaining the battery 10's true internal resistance data.

[0066] Furthermore, in an optional implementation, when the actual internal resistance of the battery 10 is detected to be greater than a first threshold while the battery 10 is in a fully charged but non-operating state, the control component 50 acquires the actual internal resistance of the battery 10 again after the battery 10 has been left to stand for a second preset period of time. If the actual internal resistance is detected to be greater than the first threshold again, it indicates that the battery 10 has reached the end of its lifespan and needs to be replaced.

[0067] After fast charging of battery 10 is completed, for example, if battery 10 is lithium-ion, the uneven distribution of lithium ions at the electrode interface will cause concentration polarization. This will result in a falsely high internal resistance reading in a short period, not necessarily due to aging of battery 10 itself. For example, after the entire device is fully charged and battery 10 reaches its full voltage, the device is in standby mode and not in operation. The control component 50 performs multiple checks within a first preset time period. If the initial internal resistance is greater than three times the initial internal resistance, no fault is reported directly; the device remains stationary for 20 minutes to eliminate polarization. After the stationary period, the load switch 20 is disconnected again, and another round of internal resistance testing is performed. If the retest result is still greater than the first threshold, battery 10 is determined to have reached the end of its lifespan, triggering the prompt component 60. If the retested internal resistance falls back below the threshold, it is determined to be a temporary high internal resistance caused by polarization, and battery 10 is considered normal; no replacement prompt is output.

[0068] Since battery 10 is in an electrochemically unbalanced state immediately after fast charging, the measured internal resistance is too high and does not reflect the true internal resistance of battery 10. Therefore, this solution does not directly assume that battery 10 has reached the end of its lifespan after detecting excessive internal resistance. Instead, it waits for battery 10 to stand for a period of time until the polarization of battery 10 is eliminated before testing. This effectively avoids the problem of battery 10 being mistakenly judged to have reached the end of its lifespan when it has not aged, thus improving the accuracy of the measurement.

[0069] Furthermore, in one optional implementation, the first preset duration is 1 minute, and the second preset duration is between 10 minutes and 30 minutes.

[0070] Of course, this embodiment is merely an example of the specific values ​​of the first preset duration and the second preset duration, but it does not limit the scope of the embodiment. Those skilled in the art can make changes according to the actual situation, as long as the same technical effect can be achieved.

[0071] In this embodiment, the first preset time is set to 1 minute. This allows for multiple measurements of the internal resistance of the battery 10 within a short period, avoiding excessively long time spans that could lead to data inaccuracies. Furthermore, this embodiment sets the resting time between 10 and 30 minutes. This time range is sufficient to eliminate the polarization effect after the lithium battery 10 is charged, while avoiding wasted time due to excessive resting time. This balances measurement reliability and efficiency.

[0072] Furthermore, in an optional embodiment, when the battery 10 is in operation, the control component 50 is configured to perform a round of multiple internal resistance detections every third preset time interval, obtaining multiple sets of internal resistance detection values, and taking the average of the multiple sets of internal resistance detection values ​​as the actual internal resistance of the battery 10. Moreover, the test duration of each round can be adjusted according to actual conditions, and the number of internal resistance detection values ​​in each round can also be adjusted.

[0073] Specifically, because the equipment is operating, the voltage of battery 10 will be lower than the initial voltage, and the detected internal resistance of battery 10 will be unstable. Since the discharge process of battery 10 is dynamic, the frequency of detecting the internal resistance of battery 10 can be, for example, testing for 2 seconds every 2 minutes, for a total of 10 tests, and then calculating the average value. That is, summing the 10 internal resistance readings and dividing by 10 gives the average value, which is taken as the actual internal resistance of battery 10. This is to prevent erroneous information caused by a single measurement deviation.

[0074] For example, when the small appliance is running, battery 10 is continuously discharging, and the current of load 30 fluctuates dynamically. Control component 50 triggers a round of detection every 2 minutes: briefly disconnecting the load switch for 2 seconds, then conducting two detection branches in a time-division manner to complete sampling and calculate a set of internal resistances; then restoring power to load 30; accumulating 10 sets of internal resistance data, removing individual extreme jump values, and taking the arithmetic mean, comparing the average value with the second threshold, which is twice the initial internal resistance; if the average value exceeds the threshold, it is determined that battery 10 is aging, and a replacement prompt is output.

[0075] When battery 10 is in a working discharge state, a dynamic electrochemical process occurs inside battery 10, which causes large fluctuations in the measured internal resistance of battery 10. Therefore, in this embodiment, multiple sets of internal resistance detection values ​​are obtained through multiple rounds of detection, and then the average value of the multiple sets of internal resistance detection values ​​is taken. This can effectively suppress the influence of dynamic changes during discharge, thereby obtaining a battery 10 internal resistance that is closer to the real state and improving the accuracy of the measurement.

[0076] Furthermore, in one alternative implementation, the third preset duration is 2 minutes.

[0077] Of course, this embodiment is merely an example of the specific value of the third preset duration, but it does not limit the scope of the embodiment. Those skilled in the art can make changes according to the actual situation, as long as the same technical effect can be achieved.

[0078] In this embodiment, the third preset duration is set to 2 minutes. This time period can not only detect the change process of the internal resistance of the battery 10 in time, but also reduce the number of sampling and calculations of the control component 50, which can reduce the power consumption of the control component 50 to a certain extent.

[0079] Secondly, this application provides a method for detecting the lifespan of a battery 10, applied to the detection circuit described in any of the above embodiments, the detection method comprising: S1. When testing the lifespan of battery 10, disconnect the load switch 20 and cut off the power supply to load 30; for details, please refer to the above embodiment, and will not be repeated here.

[0080] S2. Sequentially turn on each detection branch and collect the detection voltage corresponding to the detection resistor in each detection branch through the sampling detection terminal of the control component 50; for details, please refer to the above embodiment, and will not be repeated here.

[0081] S3. Calculate the actual internal resistance of battery 10 based on each detection voltage and the corresponding detection resistor value; see the above embodiment for details, which will not be repeated here.

[0082] S4. Obtain the operating status and power status of battery 10; if battery 10 is fully charged and not in operation, and the actual internal resistance is greater than a first threshold, then battery 10 is determined to have reached the end of its lifespan; if battery 10 is in operation, and the actual internal resistance is greater than a second threshold, then battery 10 is determined to have reached the end of its lifespan. For details, please refer to the above embodiment, which will not be repeated here.

[0083] As an extended embodiment of the method, if the battery manufacturer can provide a mapping table of different voltages, internal resistances and remaining capacity of the battery 10, and this mapping table is pre-stored in the control component 50, then after calculating the real-time internal resistance and the battery voltage E, the estimated remaining capacity of the battery 10 can be obtained by looking up the table. In addition to outputting a binary judgment of "whether it needs to be replaced", the remaining lifespan in percentage form can also be output, giving the user richer status prompts.

[0084] Thirdly, this application provides an electrical device comprising: a load 30 and a battery life detection circuit as described in any of the above embodiments.

[0085] The electrical device can be a household appliance, a testing instrument, or something similar. This embodiment is merely an example to illustrate the types of electrical devices, but it is not intended to limit the scope. Those skilled in the art can modify it according to actual circumstances, as long as the same technical effect is achieved.

[0086] This solution integrates the battery life detection circuitry into the electrical device, enabling devices equipped with the battery to have built-in self-diagnostic capabilities for battery aging, eliminating the need for external testing instruments. Since the device can autonomously identify the aging status of the battery, it solves the problem of users not knowing the remaining battery life or knowing when to replace it, thus improving product intelligence and user experience.

[0087] Furthermore, in an optional embodiment, the power device further includes a prompting component 60, which is communicatively connected to the control component 50 of the detection circuit. When the control component 50 determines that the battery 10 has reached the end of its lifespan, it drives the prompting component 60 to output a prompt message.

[0088] The prompt message can be an audio message or text. The text can be displayed on the screen of the electrical device, or it can be a light indicator. This embodiment is merely an example of the types of prompt messages and is not intended to limit the scope. Those skilled in the art can modify it according to actual circumstances, as long as the same technical effect is achieved.

[0089] In the example of a small household appliance, the prompt component 60 can be an LED indicator: a solid green light under normal conditions; a flashing red light when the battery 10 has reached the end of its lifespan; if the device has a display screen, a pop-up window will display "Battery 10 is aging, please replace battery 10 in time"; or an intermittent buzzer can be used to provide an audible reminder.

[0090] After the battery 10 reaches the end of its lifespan, the control component 50 drives the prompt component 60 to output a prompt message, thereby proactively informing the user of the aging status of the battery 10 and reminding the user to replace the battery 10 in time. This prevents the battery from being used after it has aged severely, which could lead to problems such as a sharp drop in battery life and unstable power supply, thus improving the user experience.

[0091] Although embodiments of this application have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of this application, and all such modifications and variations fall within the scope defined by the appended claims.

Claims

1. A battery life detection circuit, characterized in that, include: Battery (10); A load switch (20) is provided, one end of which is connected to one end of the battery (10), and the other end of which is connected to the load (30); the other end of the load switch (20) and the other end of the battery (10) are used together to supply power to the load (30); The detection component (40) includes at least two detection branches, each of which is connected in parallel across the two ends of the battery (10); each detection branch includes a detection switch and a detection resistor connected in series, and when the detection switch is turned on, the corresponding detection branch and the battery (10) form a detection circuit. The control component (50) has a sampling and detection terminal, which is connected between the detection switch and the detection resistor of the corresponding detection branch; the sampling and detection terminal is used to collect the detection voltage across the detection resistor and obtain the actual internal resistance of the battery (10); the control component (50) is electrically connected to the load switch (20) and the detection switch of each detection branch, respectively, and is used to control the on / off state of the load switch (20) and each detection switch; If the battery (10) is fully charged and not in operation, and the actual internal resistance is greater than the first threshold, then the lifespan of the battery (10) has expired. If the battery (10) is in operation and the actual internal resistance is greater than the second threshold, then the battery (10) has reached the end of its lifespan.

2. The detection circuit according to claim 1, characterized in that, The detection component (40) includes a first detection branch (41) and a second detection branch (42); The first detection branch (41) includes a first detection switch (411) and a first detection resistor (412), and the second detection branch (42) includes a second detection switch (421) and a second detection resistor (422).

3. The detection circuit according to claim 2, characterized in that, The voltage of the battery (10) is E, and the actual internal resistance is r; the detection voltage collected by the sampling detection terminal in the first detection branch (41) is A, and the detection voltage collected in the second detection branch (42) is B; the current flowing through the first detection branch (41) is I1, and the current flowing through the second detection branch (42) is I2; the resistance value of the first detection resistor (412) is T1, and the resistance value of the second detection resistor (422) is T2; The control component (50) is configured to calculate the actual internal resistance r of the battery (10) according to the following relationship: 1: E=I1 r+A; A=I1 T1; Equation 2: E=I2 r+B;B=I2 T2; Formula 3: r=(BA) / (A / T1-B / T2).

4. The detection circuit according to any one of claims 1 to 3, characterized in that, The battery (10) has an initial internal resistance, and the control component (50) is preset with a first threshold and a second threshold; the first threshold is 3 times the initial internal resistance, and the second threshold is 2 times the initial internal resistance.

5. The detection circuit according to claim 4, characterized in that, When the battery (10) is in a fully charged but not working state, the control component (50) is configured to perform multiple internal resistance detections on the battery (10) within a first preset time period, with each detection lasting for the first detection period.

6. The detection circuit according to claim 5, characterized in that, When the actual internal resistance of the battery (10) is detected to be greater than the first threshold when the battery (10) is in a fully charged but not working state, the control component (50) obtains the actual internal resistance of the battery (10) again after the battery (10) has been left to stand for a second preset time.

7. The detection circuit according to claim 6, characterized in that, The first preset duration is 1 minute, and the second preset duration is between 10 minutes and 30 minutes.

8. The detection circuit according to claim 4, characterized in that, When the battery (10) is in working state, the control component (50) is configured to: perform a round of multiple internal resistance detections every third preset time interval to obtain multiple sets of internal resistance detection values, and take the average value of the multiple sets of internal resistance detection values ​​as the actual internal resistance of the battery (10).

9. The detection circuit according to claim 8, characterized in that, The third preset duration is 2 minutes.

10. A method for detecting battery life, characterized in that, The detection method, applied to the detection circuit according to any one of claims 1 to 9, comprises: S1. When testing the lifespan of the battery (10), disconnect the load switch (20) and cut off the power supply to the load (30); S2. Sequentially turn on each detection branch and collect the detection voltage corresponding to the detection resistor in each detection branch through the sampling detection terminal of the control component (50); S3. Calculate the actual internal resistance of the battery (10) based on each detection voltage and the corresponding detection resistor value; S4. Obtain the working status and power status of the battery (10); if the battery (10) is fully charged and not working, and the actual internal resistance is greater than the first threshold, then the battery (10) is determined to have reached the end of its lifespan; if the battery (10) is working, and the actual internal resistance is greater than the second threshold, then the battery (10) is determined to have reached the end of its lifespan.

11. An electrical appliance, characterized in that, include: The load (30) and the detection circuit as described in any one of claims 1 to 9.

12. The electrical appliance according to claim 11, characterized in that, The electrical appliance also includes: The prompt component (60) is communicatively connected to the control component (50) of the detection circuit. When the control component (50) determines that the battery (10) has reached the end of its life, it drives the prompt component (60) to output a prompt message.

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