Battery capacity detection circuit and detection method

Abstract

The invention provides a battery capacity detection circuit and detection method. One end of a first signal link of the battery capacity detection circuit is used for being connected with a battery to be detected, and the other end is connected with a first control unit; one end of the second signal link is connected to the first signal link, and the other end is grounded; a divider resistor is arranged on the second signal link; the second control unit is configured to disconnect the second signal link before detecting the capacity of the battery to be detected; under the condition that the capacity of the battery to be detected is detected, conducting a second signal link; the first control unit is used for acquiring a first voltage signal when the second signal link is disconnected and acquiring a second voltage signal when the second signal link is connected; the first control unit is also used for obtaining the capacity of the to-be-detected battery based on the first voltage signal and the second voltage signal; the capacity of the to-be-detected battery is calculated through the first signal and the second signal, and compared with detection of a single voltage value, the detection accuracy is higher.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of battery detection, and particularly relates to a battery capacity detection circuit and a detection method. BACKGROUND

[0002] With the development of the Internet of Things, wearable devices, wireless sensor networks and portable medical devices, these battery-powered devices have increasingly high requirements for endurance and stability, and accurate detection of battery capacity has become a key to ensuring normal operation.

[0003] In related technologies, battery capacity detection is mostly performed by collecting voltage at a low current. However, some batteries have a virtual voltage and a platform voltage stage, and the voltage sampled at a low current cannot reflect the true capacity, resulting in large detection errors, especially in the later stage with less capacity, the errors are more obvious, and the accuracy requirement cannot be met. SUMMARY

[0004] The application aims to provide a battery capacity detection circuit and a detection method, and aims to solve the problem of low accuracy of the battery capacity detection circuit in the prior art.

[0005] The first aspect of the application provides a battery capacity detection circuit, which is used to detect the capacity of a battery to be detected, and comprises:

[0006] a first control unit;

[0007] a first signal link, one end of the first signal link being used to be connected with the battery to be detected, and the other end of the first signal link being connected with the first control unit;

[0008] a second signal link, one end of the second signal link being connected on the first signal link, and the other end of the second signal link being grounded; a voltage dividing resistor being arranged on the second signal link, and the second signal link having a conducting state and a disconnected state;

[0009] a second control unit, which is configured to make the second signal link in the disconnected state before detecting the capacity of the battery to be detected, and is configured to make the second signal link in the conducting state when the capacity of the battery to be detected is detected;

[0010] the first control unit is used to acquire a first voltage signal from the first signal link when the second signal link is in the disconnected state, and is used to acquire a second voltage signal from the first signal link when the second signal link is in the conducting state; and the first control unit is further used to obtain the capacity of the battery to be detected based on the first voltage signal and the second voltage signal.

[0011] In some embodiments of the present application, a power switch tube is arranged on the second signal link, the power switch tube is connected in series with the voltage dividing resistor, the power switch tube is used to control the on / off of the second signal link, and a control electrode of the power switch tube is connected to the second control unit.

[0012] In some embodiments of the present application, the power switch tube is a MOS tube or a triode.

[0013] In some embodiments of the present application, one end of the first signal link is connected to a positive electrode of the battery to be detected, and a negative electrode of the battery to be detected is grounded.

[0014] In some embodiments of the present application, the battery capacity detection circuit further comprises a power supply, and the power supply is connected to a connection point of the first signal link and the second signal link.

[0015] In some embodiments of the present application, the first control unit is configured to perform a difference operation on the first voltage signal and the second voltage signal to obtain a voltage difference, and is further configured to obtain the capacity of the battery to be detected based on the voltage difference and a capacity-voltage change table, wherein the capacity-voltage change table is used to represent the relationship between the capacity and the voltage change rate.

[0016] In some embodiments of the present application, the battery capacity detection circuit further comprises a control module, and the control module comprises the first control unit, the second control unit, and a third control unit, wherein the third control unit is configured to control the second control unit to output a control signal intermittently according to the state of the battery to be detected, and the control signal is used to control the second signal link to be in a conduction state.

[0017] In some embodiments of the present application, the first control unit and the second control unit are multiplexed.

[0018] In some embodiments of the present application, when the second signal link is in the conduction state, the battery to be detected outputs a first working current; and when the second signal link is in the off state, the battery to be detected outputs a second working current, wherein the current value of the first working current is greater than the current value of the second working current.

[0019] The second aspect of the present application further provides a battery capacity detection method, wherein the battery capacity detection method uses the battery capacity detection circuit as described above to detect the capacity of a battery to be detected.

[0020] In some embodiments of the present application, the battery capacity detection method comprises:

[0021] obtaining a capacity-voltage change table, the capacity-voltage change table being used to represent a relationship between a capacity of the battery to be detected and a change value of an output voltage of the battery to be detected;

[0022] obtaining a first voltage signal on the first signal link before the second signal link is turned on, and obtaining a second voltage signal on the first signal link after the second signal link is turned on;

[0023] calculating a voltage difference value of the first voltage signal and the second voltage signal;

[0024] determining the capacity of the battery to be detected according to the capacity-voltage change table and the voltage difference value.

[0025] In some embodiments of the present application, before the capacity-voltage change table is obtained, the following steps are further included:

[0026] obtaining a discharge time-voltage change table, the discharge time-voltage change table being used to represent a change relationship of a voltage of the battery to be detected with a discharge time;

[0027] obtaining the capacity-voltage change table based on the discharge time-voltage change table.

[0028] In some embodiments of the present application, the battery capacity detection method further includes:

[0029] obtaining a state of the battery to be detected;

[0030] controlling the second control unit to intermittently output a control signal based on the state of the battery to be detected, the control signal being used to control the second signal link to be in a turned-on state.

[0031] The application has the beneficial effects that: the battery capacity detection circuit and the detection method are used for detecting the capacity of a battery to be detected, and the battery capacity detection circuit comprises a first control unit, a first signal link, a second signal link and a second control unit; one end of the first signal link is connected with the battery to be detected, and the other end of the first signal link is connected with the first control unit; one end of the second signal link is connected on the first signal link, and the other end of the second signal link is grounded; a voltage dividing resistor is arranged on the second signal link, and the second signal link has a conduction state and a disconnection state; the second control unit is configured to make the second signal link in the disconnection state before detecting the capacity of the battery to be detected, and is configured to make the second signal link in the conduction state in the case of detecting the capacity of the battery to be detected; the first control unit is used for acquiring a first voltage signal from the first signal link in the case of the second signal link in the disconnection state, and is used for acquiring a second voltage signal from the first signal link in the case of the second signal link in the conduction state; the first control unit is further used for obtaining the capacity of the battery to be detected based on the first voltage signal and the second voltage signal; the second signal link is connected with the first signal link, the first signal and the second signal are collected in the case of the second signal link being turned on or turned off, and the capacity of the battery to be detected is calculated based on the first signal and the second signal, so that the capacity detection of the battery to be detected is realized. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 The frame structure schematic diagram of the battery capacity detection circuit is provided for an embodiment of the application.

[0033] Figure 2 The frame structure schematic diagram of the battery capacity detection circuit is provided for another embodiment of the application.

[0034] Figure 3 The circuit structure schematic diagram of the battery capacity detection circuit is provided for an embodiment of the application.

[0035] Figure 4 The capacity voltage change schematic diagram of the battery capacity detection circuit is provided for an embodiment of the application.

[0036] Figure 5 The step schematic diagram of the battery capacity detection method is provided for an embodiment of the application.

[0037] Figure 6 The step schematic diagram of the battery capacity detection method is provided for another embodiment of the application.

[0038] Specific element symbol explanation: 100 - first control unit, 200 - second control unit, 300 - first signal link, 400 - second signal link, 410 - voltage dividing resistor, 420 - power switch tube, 500 - battery to be detected, VCC - power supply, Q1 - triode. DETAILED DESCRIPTION

[0039] In order to make the technical problems to be solved by the present application, the technical solutions and beneficial effects clearer, the present application will be further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0040] It should be noted that when an element is referred to as "being disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as "being connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0041] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0042] It should be noted that, with the rapid popularization of Internet of Things (IoT), wearable devices (such as smart watches), wireless sensor networks and portable medical devices, the demand for endurance and running stability of such battery-powered electronic devices is increasingly stringent. As the core energy component, the accurate detection of the remaining capacity of the battery directly affects the use experience and functional reliability of the device - for example, smart watches need to accurately display the remaining power to avoid sudden shutdown, and medical monitoring devices need to ensure continuous operation through capacity warning. Therefore, in the field of low-power electronic devices, real-time and accurate detection of battery capacity has become a key technical requirement to ensure efficient operation of the device.

[0043] The current mainstream battery capacity detection method is based on voltage sampling under low current (usually microampere level). However, this method has significant defects: for example, in the discharge process of a common button battery such as CR2032, there is a clear "virtual voltage" stage (the voltage quickly drops from 3.3V to 3.0V in the initial stage) and a "platform voltage" stage (the voltage remains relatively stable for a long time), even if the actual capacity of the battery has decreased significantly, the sampling voltage under low current may still be maintained at a high level, resulting in a large deviation between the detection result and the true capacity. Especially in the later stage of use when the battery capacity is low, the voltage decreases rapidly with the capacity, but low current sampling is difficult to capture this subtle difference, further exacerbating the detection error, which cannot meet the accuracy requirements of the device for capacity warning.

[0044] Based on this, the battery capacity detection circuit and detection method in the related art are improved.

[0045] Please refer to Figure 1 , Figure 1 The framework structure diagram of the battery capacity detection circuit provided by the embodiment of the application is shown; the battery capacity detection circuit of the embodiment of the application is used for detecting the capacity of a battery to be detected 500, and comprises a first control unit 100, a first signal link 300, a second signal link 400 and a second control unit 200; one end of the first signal link 300 is used for being connected with the battery to be detected 500, and the other end of the first signal link 300 is connected with the first control unit 100; one end of the second signal link 400 is connected on the first signal link 300, and the other end of the second signal link 400 is grounded; a voltage dividing resistor 410 is arranged on the second signal link 400, and the second signal link 400 has a conduction state and a disconnection state; the second control unit 200 is configured to make the second signal link 400 in the disconnection state before detecting the capacity of the battery to be detected 500, and is configured to make the second signal link 400 in the conduction state when the capacity of the battery to be detected 500 is detected; the first control unit 100 is used for acquiring a first voltage signal from the first signal link 300 when the second signal link 400 is in the disconnection state, and is used for acquiring a second voltage signal from the first signal link when the second signal link is in the conduction state; and the first control unit 100 is further used for obtaining the capacity of the battery to be detected 500 based on the first voltage signal and the second voltage signal.

[0046] It needs to be explained that the first control unit 100 is a control component with signal receiving, processing and calculation functions, which can analyze and process the input electrical signal and output the result according to the preset logic, and is the core part of data processing in the circuit. The first signal link 300 is a path for transmitting electrical signals, which can stably transmit the electrical signals of the to-be-detected object to the first control unit 100, providing a physical path for signal acquisition and ensuring the integrity of the signals during transmission. The to-be-detected battery 500 is a battery that needs to be detected for capacity, which is an electrical energy storage device, and its capacity reflects the amount of stored electrical energy, which is the target object of detection. The second signal link 400 is an auxiliary signal path connected to the first signal link 300, one end of which is connected to the first signal link 300 and the other end is grounded, which can change the overall load of the circuit by state switching and assist in signal acquisition in multiple states. The voltage dividing resistor 410 is a resistor element arranged in the circuit, which shares the voltage in the circuit through its own resistance characteristics, and can adjust the voltage value of a node in the circuit to facilitate the acquisition and processing of signals by the control unit. The on state is the state of the circuit path, at this time the current can flow along the second signal link 400, so that the link participates in the circuit work and changes the load characteristics of the circuit. The off state is the state of the circuit being disconnected, at this time the current cannot flow along the second signal link 400, and the link does not participate in the circuit work, and the circuit remains in a low-load state. The second control unit 200 is a component for controlling the state of the circuit, which can switch the on and off states of the second signal link 400 according to the detection requirements to realize the conversion of the circuit working mode.

[0047] It can be understood that the second control unit 200 is configured to detect the off state of the second signal link 400 before detection and the on state of the second signal link 400 during detection. In the non-detection phase, the disconnected second signal link 400 can avoid the voltage dividing resistor 410 continuously consuming battery power, which is conducive to reducing the standby power consumption of the circuit. In the detection phase, the on second signal link 400 introduces a load through the voltage dividing resistor 410, so that the first control unit 100 can collect the real voltage of the battery under load (avoiding the influence of false voltage), which is conducive to improving the pertinence of signal acquisition. The first control unit 100 obtains the capacity of the to-be-detected battery 500 based on the first voltage signal and the second voltage signal, which can analyze the characteristics related to the capacity of the battery, such as internal resistance and discharge capacity, by comparing the voltage changes of the battery under low load and with load, and the characteristics of the voltage dividing resistor 410, which is conducive to improving the accuracy of capacity detection. The overall setting realizes state switching and double signal comparison, which not only guarantees low power consumption but also improves detection accuracy, which is conducive to adapting to the capacity detection needs of different types of batteries.

[0048] In some embodiments of the present application, please refer to Figure 2 , Figure 2A framework structure schematic diagram of the battery capacity detection circuit provided by the embodiment is shown; the power switch tube 420 is arranged on the second signal link 400 of the embodiment, the power switch tube 420 is in series with the voltage dividing resistor 410, the power switch tube 420 is used for controlling the on / off of the second signal link 400, and the control electrode of the power switch tube 420 is connected with the second control unit 200.

[0049] It needs to be explained that the power switch tube 420 is a kind of semiconductor device with switching characteristics, can realize the conduction and disconnection of the circuit through the control signal, can bear certain power, is commonly used for controlling the circuit path with large current, and is a key element for realizing state switching in the circuit.

[0050] It can be understood that the power switch tube 420 can be switched on and off quickly under the control of the second control unit 200, and then the on / off of the second signal link 400 is accurately controlled. Compared with other switching modes, the power switch tube 420 has fast response speed, can ensure that the second signal link 400 is turned on in time during detection and is disconnected quickly in the non-detection state, and reduces invalid power consumption. At the same time, the power switch tube 420 is arranged in series with the voltage dividing resistor 410, the current of the second signal link 400 can be completely cut off in the off state of the switch tube, the leakage or continuous energy consumption of the voltage dividing resistor 410 in the non-detection stage is avoided, and the standby power consumption of the circuit is further reduced.

[0051] In some embodiments of the present application, please refer to Figure 3 , Figure 3 A circuit structure schematic diagram of the battery capacity detection circuit provided by the embodiment is shown; the power switch tube 420 of the embodiment is a MOS tube or a triode Q1 (as shown in Figure 3 .

[0052] It needs to be explained that the MOS tube is a kind of semiconductor device for controlling current by using electric field effect, has the characteristics of high input resistance and low power consumption, is commonly used as a switching element in electronic circuits, and realizes the switching of on and off states by controlling the gate voltage. The triode Q1 is a kind of semiconductor device with current amplification effect, which is composed of three electrodes, can control the current between the collector and the emitter through the base current, is commonly used as a switching or amplifying element in the circuit, and can quickly respond to the control signal to realize state switching.

[0053] It can be understood that, by arranging the power switch tube 420 as a MOS tube or a triode Q1, the MOS tube has high input resistance and consumes almost no current in the off state, which is conducive to further reducing the standby power consumption when the second signal link 400 is disconnected; the triode Q1 has fast response speed, can quickly switch on and off under the control of the second control unit 200, ensures that the second signal link 400 is turned on in time during detection, and guarantees the rapid acquisition of the second voltage signal.

[0054] In some embodiments, the power switch tube 420 is an NPN triode Q1.

[0055] It should be explained that the NPN triode Q1 is a triode Q1 composed of two N-type semiconductors and one P-type semiconductor, having three electrodes of emitter, base and collector, and can make the emitter and the collector conduct by inputting a forward current to the base, and is in a cut-off state when there is no base current. It is a commonly used switching element in circuits, and has the characteristics of fast response speed and simple control mode.

[0056] It can be understood that the NPN triode Q1 can be turned on and off by inputting a control signal to the base through the second control unit 200: when the battery capacity needs to be detected, the second control unit 200 inputs a forward current to the base to make the triode Q1 conduct, the second signal link 400 forms a path, and the voltage dividing resistor 410 is connected to the circuit; when there is no need to detect, there is no current in the base, the triode Q1 is cut off, the second signal link 400 is disconnected, and the voltage dividing resistor 410 is prevented from consuming energy.

[0057] In some embodiments of the present application, please refer to Figure 3 , in this embodiment, the first signal link 300 of the embodiment is connected to the positive electrode of the battery to be detected 500, and the negative electrode of the battery to be detected 500 is grounded.

[0058] In some embodiments of the present application, please refer to Figure 3 , the battery capacity detection circuit of the embodiment further comprises a power supply VCC connected to the connection point of the first signal link 300 and the second signal link 400.

[0059] It should be explained that the power supply VCC is a device that provides working power for each functional module (such as control unit, switching element, etc.) in the circuit, can output stable voltage, and ensures that each component operates normally during detection, and is the energy source for maintaining the function of the circuit.

[0060] It can be understood that when the second signal link 400 is in a disconnected state, the first voltage signal obtained by the first control unit 100 from the first signal link 300 is pulled up in value under the action of the power supply VCC, avoiding the sampling ambiguity caused by the too small value of the battery to be detected 500 itself (such as the virtual voltage in the low-power state); when the second signal link 400 is in a conductive state, the battery voltage is pulled down by the voltage dividing resistor 410, and at this time the power supply VCC can still ensure that the second voltage signal is maintained in a value range that can be accurately sampled, avoiding the difficulty of accurate identification due to the too low voltage value after pulling down.

[0061] The setting can make the first control unit 100 (such as an ADC sampling circuit) capture the subtle changes of the voltage signal more clearly by amplifying the signal value, reduce the quantization error caused by the too small signal value (such as the reading deviation caused by insufficient sampling resolution), and improve the measurement accuracy of the first voltage signal and the second voltage signal. Meanwhile, the stable voltage provided by the power supply VCC provides energy support for the operation of the control unit and the switching element, ensures the stable operation of the circuit during the signal value adjustment process, and finally helps to improve the accuracy of the battery capacity detection by cooperating with the signal analysis of the quantization algorithm.

[0062] In some embodiments of the present application, please refer to Figure 4 , Figure 4 a capacity voltage change diagram of the battery capacity detection circuit provided by the present embodiment is shown; Figure 4 the abscissa is the discharge time, and the ordinate is the discharge voltage, Figure 4 In the example of taking a CR2032 battery as the battery to be detected 500 and R3 as the voltage dividing resistor 410, it can be seen that the CR2032 battery will have a very fast voltage drop from about 3.3V to 3.00V in the initial stage, which is usually called "virtual voltage"; then the voltage will be relatively stable at a voltage value for a long period of time, which is called "platform voltage"; finally, the voltage will gradually decrease with the decrease of the capacity (discharge time) in the later stage of use when the capacity is low, and the capacity will be consumed. The first control unit 100 of the present embodiment is configured to perform difference operation based on the first voltage signal and the second voltage signal to obtain a voltage difference, and is also configured to obtain the capacity of the battery to be detected 500 based on the voltage difference and a capacity voltage change table, and the capacity voltage change table is configured to represent the relationship between the capacity and the voltage change rate.

[0063] It can be understood that the voltage difference can effectively filter out the interference of the virtual voltage of the battery - the first voltage signal reflects the voltage without load (which may include the virtual voltage), the second voltage signal reflects the real voltage under load, and the difference between the two can more truly reflect the actual discharge characteristics of the battery, avoiding the misjudgment caused by a single voltage signal. At the same time, the capacity voltage change table pre-stores the corresponding relationship between the capacity and the voltage change rate, so that the first control unit 100 can quickly match the corresponding capacity range through the voltage difference without complex real-time calculation, simplifying the operation process and helping to reduce the power consumption of the control unit (in line with the low-power design requirement). This method based on the preset corresponding relationship can establish a clear association between the voltage difference, which is a directly measurable electrical signal, and the battery capacity, which is a target parameter, reduce the detection deviation caused by individual differences of the battery or environmental factors, and improve the stability of the capacity calculation.

[0064] In some embodiments of the present application, please continue to refer to Figure 3In this embodiment, the control module is taken as an example of a single-chip microcomputer. The battery capacity detection circuit of this embodiment further comprises a control module. The control module comprises a first control unit 100, a second control unit 200, and a third control unit. The third control unit is configured to control the second control unit 200 to intermittently output a control signal according to the state of the battery 500 to be detected. The control signal is configured to control the second signal link 400 to be in a conducting state.

[0065] It can be understood that the third control unit can dynamically adjust the output timing and frequency of the control signal according to the state of the battery (such as voltage stability, last detection result, etc.), so as to avoid meaningless frequent detection. When the state of the battery is relatively stable, the third control unit controls the second control unit 200 to reduce the output frequency of the control signal, so that the second signal link 400 is in a disconnected state for a long time, thereby reducing the battery energy consumption caused by the load access. When the state of the battery fluctuates obviously (such as voltage drop), the third control unit controls the second control unit 200 to increase the output of the control signal, so as to realize timely monitoring of the battery capacity through more frequent conducting state. This on-demand intermittent control mode can not only reduce unnecessary energy consumption while ensuring the timeliness of detection, but also meet the core demand of low-power detection, and can avoid additional damage to the battery caused by continuous detection.

[0066] In some embodiments of the present application, the first control unit 100 and the second control unit 200 are multiplexed.

[0067] In some embodiments of the present application, in the case where the second signal link 400 is in a conducting state, the battery 500 to be detected outputs a first working current; in the case where the second signal link 400 is in a disconnected state, the battery 500 to be detected outputs a second working current. The current value of the first working current is greater than that of the second working current.

[0068] It should be explained that the first working current is the current output by the battery 500 to be detected when the second signal link 400 is in a conducting state. At this time, since the second signal link 400 accesses the load (such as the voltage dividing resistor 410), the overall impedance of the circuit is reduced, so that the current output by the battery is increased, which is used to reflect the discharge characteristics of the battery under the load state.

[0069] The second working current is the current output by the battery 500 to be detected when the second signal link 400 is in a disconnected state. At this time, the circuit only maintains the basic signal acquisition requirement, the load is small, and the current output by the battery is small, so as to reduce the energy consumption in the non-detection stage.

[0070] It can be understood that, in the detection stage (the second signal link 400 is turned on), the larger first working current can simulate the discharge state of the battery under the actual load, so that the battery voltage is pulled down due to the large current and presents a characteristic related to the remaining capacity (such as the voltage difference of different capacity batteries in the document under large current), which is beneficial to the first control unit 100 to collect the second voltage signal which can truly reflect the battery capacity. In the non-detection stage (the second signal link 400 is disconnected), the smaller second working current can reduce the energy consumption of the battery, avoid the battery loss caused by continuous large current discharge, and meet the needs of low-power detection. The dynamic change of such current is linked with the on-off state of the second signal link 400, so that the battery can provide effective voltage signal under load during detection and maintain low-power state during idle, which takes into account the detection accuracy and energy saving needs.

[0071] Further, in order to better implement the battery capacity detection method in any of the above embodiments, on the basis of the above battery capacity detection method, the present embodiment also provides a battery capacity detection method, which uses the above battery capacity detection circuit to detect the capacity of the battery 500 to be detected.

[0072] In some embodiments of the present application, please refer to Figure 5 , Figure 5 The steps of the battery capacity detection method provided by the present embodiment are shown, and the battery capacity detection method of the present embodiment includes:

[0073] S100: Obtain a capacity voltage change table, which is used to represent the relationship between the capacity of the battery 500 to be detected and the change value of the output voltage of the battery 500 to be detected; Specifically, the capacity voltage change table can be a table or a curve established by experiment or statistics, which records the corresponding relationship between the output voltage change value and the capacity of the battery 500 to be detected under different remaining capacities, and provides a direct basis for inferring the capacity from the voltage signal.

[0074] S200: Obtain the first voltage signal on the first signal link 300 before the second signal link 400 is turned on, and obtain the second voltage signal on the first signal link 300 after the second signal link 400 is turned on; Specifically, a voltage dividing resistor 410 is arranged on the second signal link 400, and the discharge of the battery 500 to be detected after connecting the voltage dividing resistor 410 causes the voltage signal on the first signal link 300 to change, and the first voltage signal and the second voltage signal are the voltage signals before and after the change.

[0075] S300: Calculate the voltage difference between the first voltage signal and the second voltage signal; Specifically, different remaining capacities will result in different voltage pull-down amplitudes, and the voltage difference can capture such amplitude difference, which is beneficial to convert the abstract battery state into a quantifiable electrical signal indicator, and provides a clear quantitative basis for capacity inference.

[0076] S400: Determine the capacity of the battery 500 to be detected according to the capacity-voltage change table and the voltage difference value. Specifically, the measured voltage difference value is matched with the preset capacity-change value relationship, so that the remaining capacity of the battery can be quickly obtained without complex real-time operation.

[0077] In some embodiments of the present application, please refer to Figure 6 , Figure 6 The steps of the voltage capacity detection method provided by the present embodiment are shown in the schematic diagram, and before step S100, the following steps are further included:

[0078] S10: Obtain a discharge time-voltage change table, which is used to represent the change relationship between the voltage of the battery 500 to be detected and the discharge time; specifically, the discharge time-voltage change table is a curve diagram as shown in Figure 4 .

[0079] S20: Obtain a capacity-voltage change table based on the discharge time-voltage change table.

[0080] In some embodiments of the present application, the battery capacity detection method further includes:

[0081] Obtain the state of the battery 500 to be detected; specifically, the state of the battery 500 to be detected refers to the real-time situation of the battery 500 to be detected in the use process, including but not limited to the current voltage level, the discharge stage (such as the virtual voltage stage, the platform voltage stage, etc.), the state change trend reflected by the historical detection data, etc., which is the basis for judging whether the battery needs to be detected.

[0082] Based on the state of the battery 500 to be detected, the second control unit 200 intermittently outputs a control signal, and the control signal is used to control the second signal link 400 to be in the conduction state. Specifically, by obtaining the state of the battery, it can be accurately judged whether the battery is in the stage that needs to be detected-for example, when the battery is in the platform stage with relatively stable voltage, the detection frequency can be reduced; when the battery voltage enters the rapid decline stage, the detection frequency can be increased, so that the detection is more targeted, and meaningless frequent detection is avoided.

[0083] In the above embodiments, the description of each embodiment has its own emphasis, and the parts not described or recorded in a certain embodiment can be referred to the related description of other embodiments.

[0084] The foregoing detailed description of the application has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the application to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teachings. It is intended that the scope of the application be limited not with this detailed description, but rather by the claims appended hereto.

[0085] Also, the use of "an" or "one" to introduce "elements, " "circuits" and / or "steps" throughout the specification, including the claims, should not be interpreted as meaning that there is only one of these elements, circuits and / or steps. Further, the use of "a" or "an" when used in conjunction with the term "comprising" in the claims should not be interpreted as meaning that there is only one of the elements, circuits and / or steps that "comprise" the combination.

[0086] Similarly, it is intended that only claims that specifically recite those exact elements as "means for" performing the specified function or step be presented as being meant for 35 U.S.C. § 112, paragraph 6. Moreover, none of the claims are intended to embrace subject matter that fails to satisfy the requirements of 35 U.S.C. § 101, 102, or 103, as well as any other requirements of the patent statutes and regulations.

[0087] The embodiments described above are intended to be illustrative only and in no way limit the scope of the present application. It will thus be apparent that those skilled in the art can modify the application in view of the above descriptions without departing from the scope and spirit of the application. What is intended to be the application is limited only by the following claims - a patent issuing thereon.

Claims

1. A battery capacity detection circuit, characterized by, The battery capacity detection circuit is used for detecting the capacity of a battery to be detected, and comprises: a first control unit; a first signal link, one end of the first signal link being used for connection with the battery to be detected, and the other end of the first signal link being connected with the first control unit; a second signal link, one end of the second signal link being connected on the first signal link, and the other end of the second signal link being grounded; a voltage dividing resistor being arranged on the second signal link, the second signal link having a conducting state and a disconnected state; a second control unit, the second control unit being configured to make the second signal link in the disconnected state before detecting the capacity of the battery to be detected, and being configured to make the second signal link in the conducting state in the case of detecting the capacity of the battery to be detected; the first control unit being used for acquiring a first voltage signal from the first signal link in the case of the second signal link being in the disconnected state, and being used for acquiring a second voltage signal from the first signal link in the case of the second signal link being in the conducting state; and the first control unit being further used for obtaining the capacity of the battery to be detected based on the first voltage signal and the second voltage signal.

2. The battery capacity detection circuit according to claim 1, characterized by, a power switch tube being arranged on the second signal link, the power switch tube being connected in series with the voltage dividing resistor, and the power switch tube being used for controlling the on / off of the second signal link, a control electrode of the power switch tube being connected with the second control unit.

3. The battery capacity detection circuit according to claim 2, characterized by, The power switch tube is a MOS tube or a triode.

4. The battery capacity detection circuit according to claim 1, characterized by, One end of the first signal link is connected with a positive electrode of the battery to be detected, and a negative electrode of the battery to be detected is grounded.

5. The battery capacity detection circuit according to claim 1, wherein The battery capacity detection circuit further comprises a power supply, the power supply being connected on a connection point of the first signal link and the second signal link.

6. The battery capacity detection circuit of claim 1, wherein The first control unit is used for performing difference operation based on the first voltage signal and the second voltage signal to obtain a voltage difference, and is further used for obtaining the capacity of the battery to be detected based on the voltage difference and a capacity-voltage change table, the capacity-voltage change table being used for representing the relationship between the capacity and the voltage change rate.

7. The battery capacity detection circuit of claim 1, wherein The battery capacity detection circuit further comprises a control module, the control module comprising the first control unit, the second control unit and a third control unit, the third control unit being used for controlling the second control unit to output a control signal intermittently according to the state of the battery to be detected, the control signal being used for controlling the second signal link to be in the conducting state.

8. The battery capacity detection circuit according to any one of claims 1 to 7, characterized by The first control unit is multiplexed with the second control unit.

9. The battery capacity detection circuit according to any one of claims 1 to 7, characterized by In the case of the second signal link being in the conducting state, the battery to be detected outputs a first working current; and in the case of the second signal link being in the disconnected state, the battery to be detected outputs a second working current, the current value of the first working current being greater than the current value of the second working current.

10. A battery capacity detection method characterized by, The battery capacity detection method adopts the battery capacity detection circuit according to any one of claims 1 to 9 to detect the capacity of a battery to be detected.

11. The battery capacity detection method according to claim 10, wherein The battery capacity detection method comprises: obtaining a capacity-voltage change table, the capacity-voltage change table being used to represent a relationship between a capacity of the battery to be detected and a change value of an output voltage of the battery to be detected; obtaining a first voltage signal on the first signal link before the second signal link is turned on, and obtaining a second voltage signal on the first signal link after the second signal link is turned on; calculating a voltage difference value of the first voltage signal and the second voltage signal; determining the capacity of the battery to be detected according to the capacity-voltage change table and the voltage difference value.

12. The battery capacity detection method according to claim 11, wherein Before obtaining the capacity-voltage change table, the method further comprises: obtaining a discharge time-voltage change table, the discharge time-voltage change table being used to represent a change relationship of a voltage of the battery to be detected with a discharge time; obtaining the capacity-voltage change table based on the discharge time-voltage change table.

13. The battery capacity detection method according to claim 11, wherein The battery capacity detection method further comprises: obtaining a state of the battery to be detected; controlling the second control unit to intermittently output a control signal based on the state of the battery to be detected, the control signal being used to control the second signal link to be in a turned-on state.

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