Conversion circuit and control chip for converting secondary battery into dry battery

Abstract

The utility model discloses a kind of conversion circuit and control chip of secondary battery conversion dry battery, the conversion circuit of secondary battery conversion dry battery, including temperature detection circuit, charging current control circuit and discharge voltage control circuit;Temperature detection circuit is used to detect ambient temperature, and output temperature detection signal;Charging current control circuit is connected with external power supply, temperature detection circuit and secondary battery cell, for when secondary battery cell is in charging state, according to ambient temperature, adjust the charging current of secondary battery cell;Discharge voltage control circuit is connected with secondary battery cell, temperature detection circuit and voltage output end, for when secondary battery cell is in discharging state, according to ambient temperature, adjust the discharge voltage of secondary battery cell, according to ambient temperature, adjust charging current or discharge voltage, avoid the situation that temperature is too high and cannot normally charge and discharge, guarantee secondary battery conversion dry battery control chip safety and improve user experience.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a conversion circuit and control chip for converting a secondary battery to a dry cell battery. Background Technology

[0002] Currently, lithium-ion battery control chips generally employ multi-stage control strategies during charging and discharging. The charging stage typically includes three processes: trickle charging, constant current charging (CC), and constant voltage charging (CV). During the constant current charging stage, the high operating current causes a significant increase in chip temperature. When the chip temperature exceeds the protection threshold, the charging circuit is either directly cut off, preventing the battery from fully charging, or the original charging parameters are maintained, potentially causing thermal damage to the chip. The discharging stage primarily uses two modes: constant current discharge (CCD) and constant power discharge (CPD). Under high-current discharge conditions, chip overheating also exists. Existing protection mechanisms typically employ simple temperature-based shutdown, which can lead to sudden power outages in electrical equipment, severely impacting user experience. Utility Model Content

[0003] This utility model provides a conversion circuit and control chip for converting secondary batteries to dry batteries, in order to solve the problems of poor safety and user experience in the charging and discharging process of existing secondary battery to dry battery control chips.

[0004] A conversion circuit for converting a secondary battery to a dry cell battery includes a temperature detection circuit, a charging current control circuit, and a discharging voltage control circuit.

[0005] The temperature detection circuit is used to detect the ambient temperature and output a temperature detection signal;

[0006] The charging current control circuit is connected to the external power supply, the temperature detection circuit, and the secondary battery cell, and is used to adjust the charging current of the secondary battery cell according to the ambient temperature when the secondary battery cell is in the charging state.

[0007] The discharge voltage control circuit is connected to the secondary battery cell, the temperature detection circuit, and the voltage output terminal, and is used to adjust the discharge voltage of the secondary battery cell according to the ambient temperature when the secondary battery cell is in a discharge state.

[0008] Furthermore, the temperature detection circuit includes a thermistor and a signal acquisition circuit;

[0009] The thermistor is used to output a temperature analog signal based on the ambient temperature;

[0010] The signal acquisition circuit is connected to the thermistor, the charging current control circuit, and the discharging voltage control circuit, and is used to acquire the temperature analog signal and output the temperature detection signal.

[0011] Furthermore, the thermistor includes a thermistor transistor or a thermistor.

[0012] Furthermore, the charging current control circuit includes a first operational amplifier, a second operational amplifier, and a current adjustment circuit;

[0013] The first input terminal of the first operational amplifier is connected to the temperature detection circuit, the second input terminal of the first operational amplifier is used to connect to the first reference voltage terminal, and the output terminal of the first operational amplifier is used to output a first voltage according to the temperature detection signal and the first reference voltage provided by the first reference voltage terminal;

[0014] The first input terminal of the second operational amplifier is connected to the output terminal of the first operational amplifier, the second input terminal of the second operational amplifier is connected to the second reference voltage terminal, and the output terminal of the second operational amplifier is used to output a second voltage according to the first voltage and the second reference voltage provided by the second reference voltage terminal;

[0015] The input terminal of the current adjustment circuit is connected to the external power supply, the output terminal of the current adjustment circuit is connected to the secondary battery cell, and the control terminal of the current adjustment circuit is connected to the output terminal of the second operational amplifier, for adjusting the charging current of the secondary battery cell according to the second voltage.

[0016] Furthermore, the current adjustment circuit includes a first transistor;

[0017] The first terminal of the first transistor is connected to the external power supply, the second terminal of the first transistor is connected to the secondary battery cell, and the third terminal of the first transistor is connected to the output terminal of the second operational amplifier.

[0018] Furthermore, the first transistor is a PMOS transistor, with its first terminal being the source, its second terminal being the drain, and its third terminal being the gate.

[0019] Furthermore, the charging current control circuit also includes a third operational amplifier;

[0020] The first input terminal of the third operational amplifier is connected to the temperature detection circuit, the second input terminal of the third operational amplifier is used to connect to the third reference voltage terminal, and the output terminal of the third operational amplifier is connected to the control terminal of the current adjustment circuit, for outputting a third voltage to the control terminal of the current adjustment circuit according to the temperature detection signal and the third reference voltage provided by the third reference voltage terminal; the third reference voltage is greater than the first reference voltage.

[0021] Furthermore, the discharge voltage control circuit includes a reference selection circuit and a step-down circuit;

[0022] The reference selection circuit is connected to the temperature detection circuit and is used to select a target reference voltage corresponding to the temperature detection signal based on the temperature detection signal.

[0023] The step-down circuit is connected to the reference selection circuit, the secondary battery cell, and the voltage output terminal, and is used to output a discharge voltage corresponding to the target reference voltage according to the target reference voltage.

[0024] Furthermore, the step-down circuit is a switching step-down circuit.

[0025] A secondary battery to dry battery control chip includes the aforementioned secondary battery to dry battery conversion circuit.

[0026] This utility model provides a conversion circuit and control chip for converting a secondary battery to a dry cell battery. The conversion circuit includes a temperature detection circuit, a charging current control circuit, and a discharging voltage control circuit. The temperature detection circuit detects the ambient temperature and outputs a temperature detection signal. The charging current control circuit is connected to an external power supply, the temperature detection circuit, and the secondary battery cell. When the secondary battery cell is charging, it adjusts the charging current of the secondary battery cell according to the ambient temperature. The discharging voltage control circuit is connected to the secondary battery cell, the temperature detection circuit, and a voltage output terminal. When the secondary battery cell is discharging, it adjusts the discharging voltage of the secondary battery cell according to the ambient temperature. This allows for adjustment of the charging current or discharging voltage based on the ambient temperature, preventing situations where charging and discharging cannot proceed normally due to excessively high temperatures. This ensures the safety of the secondary battery to dry cell battery control chip while improving the user experience. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of a secondary battery to dry cell conversion circuit in one embodiment of the present invention;

[0029] Figure 2 This is another schematic diagram of the conversion circuit from secondary battery to dry cell in one embodiment of this utility model.

[0030] In the diagram: 1. Temperature detection circuit; 11. Thermistor; 12. Signal acquisition circuit; 2. Charging current control circuit; 21. First operational amplifier; 22. Second operational amplifier; 23. Current adjustment circuit; 231. First transistor; 24. Third operational amplifier; 3. Discharge voltage control circuit; 31. Reference selection circuit; 32. Buck circuit; 4. Secondary battery cell. Detailed Implementation

[0031] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present utility model.

[0032] It should be understood that this invention can be embodied in various forms and should not be construed as being limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of this invention to those skilled in the art. In the drawings, for clarity, the dimensions of layers and regions, as well as their relative dimensions, may be exaggerated. The same reference numerals denote the same elements throughout.

[0033] It should be understood that when an element or layer is referred to as "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the teachings of this utility model, the first element, component, area, layer, or portion discussed below may be referred to as the second element, component, area, layer, or portion.

[0034] Spatial relation terms such as “below,” “under,” “below,” “under,” “above,” “above,” etc., are used herein for convenience of description to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms are intended to also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, then the element or feature described as “below,” “under,” or “below” other elements or features will be oriented “above” other elements or features. Therefore, the exemplary terms “below” and “under” can include both above and below orientations. The device may be otherwise oriented (rotated 90 degrees or otherwise) and the spatial descriptive terms used herein will be interpreted accordingly.

[0035] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising” and / or “including,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0036] To fully understand this utility model, detailed structures and steps will be presented in the following description to illustrate the technical solution proposed by this utility model. Preferred embodiments of this utility model are described in detail below; however, in addition to these detailed descriptions, this utility model may have other embodiments.

[0037] This embodiment provides a secondary battery to dry cell conversion circuit, integrated into a secondary battery to dry cell control chip. The secondary battery to dry cell control chip is assembled in the secondary battery to dry cell. The secondary battery to dry cell includes the secondary battery to dry cell control chip and a secondary battery cell 4. The secondary battery cell 4 is connected to the secondary battery to dry cell control chip. For example, the secondary battery cell 4 can be a lithium-ion cell or a sodium-ion cell.

[0038] This embodiment provides a conversion circuit for converting a secondary battery to a dry cell battery, such as... Figure 1As shown, it includes a temperature detection circuit 1, a charging current control circuit 2, and a discharging voltage control circuit 3. The temperature detection circuit 1 is used to detect the ambient temperature and output a temperature detection signal. The charging current control circuit 2 is connected to the external power supply VIN, the temperature detection circuit 1, and the secondary battery cell 4. It is used to adjust the charging current of the secondary battery cell 4 according to the ambient temperature when the secondary battery cell 4 is in the charging state. The discharging voltage control circuit 3 is connected to the secondary battery cell 4, the temperature detection circuit 1, and the voltage output terminal VOUT. It is used to adjust the discharging voltage of the secondary battery cell 4 according to the ambient temperature when the secondary battery cell 4 is in the discharging state.

[0039] The ambient temperature refers to the internal ambient temperature of the secondary battery to dry cell chip. The external power source VIN includes a charger or energy storage device for charging the secondary battery cell 4.

[0040] As an example, when the secondary battery cell 4 is charging, the ambient temperature is detected by the temperature detection circuit 1, and a temperature detection signal is output. This allows the charging current control circuit 2 to adjust the charging current based on the temperature detection signal corresponding to the ambient temperature. For example, when the ambient temperature is too high, the charging current is reduced to ensure that the secondary battery to dry cell control chip is not damaged and the discharge is not interrupted, thus preventing the secondary battery to dry cell from being incompletely charged and improving the charging efficiency of the secondary battery to dry cell.

[0041] When the secondary battery cell 4 discharges, the ambient temperature is detected by the temperature detection circuit 1, and a temperature detection signal is output. This allows the discharge voltage control circuit 3 to adjust the discharge voltage according to the temperature detection signal corresponding to the ambient temperature. For example, when the ambient temperature is too high, the discharge voltage is reduced to ensure that the secondary battery to dry battery control chip is not damaged and the discharge is not stopped, thus preventing the battery from running out of power and improving the battery life when switching from secondary battery to dry battery.

[0042] In this embodiment, the secondary battery to dry cell conversion circuit includes a temperature detection circuit 1, a charging current control circuit 2, and a discharging voltage control circuit 3. The temperature detection circuit 1 is used to detect the ambient temperature and output a temperature detection signal. The charging current control circuit 2 is connected to the external power supply VIN, the temperature detection circuit 1, and the secondary battery cell 4. When the secondary battery cell 4 is in a charging state, it adjusts the charging current of the secondary battery cell 4 according to the ambient temperature. The discharging voltage control circuit 3 is connected to the secondary battery cell 4, the temperature detection circuit 1, and the voltage output terminal VOUT. When the secondary battery cell 4 is in a discharging state, it adjusts the discharging voltage of the secondary battery cell 4 according to the ambient temperature. Thus, by adjusting the charging current or discharging voltage according to the ambient temperature, the circuit avoids the situation where normal charging and discharging cannot be performed when the temperature is too high. This ensures the safety of the secondary battery to dry cell control chip while improving the user experience.

[0043] In one embodiment, such as Figure 2 As shown, the temperature detection circuit 1 includes a thermistor 11 and a signal acquisition circuit 12; the thermistor 11 is used to output a temperature analog signal according to the ambient temperature; the signal acquisition circuit 12 is connected to the thermistor 11, the charging current control circuit 2 and the discharging voltage control circuit 3, and is used to acquire the temperature analog signal and output a temperature detection signal.

[0044] Furthermore, the thermistor 11 includes a thermistor transistor or a thermistor.

[0045] Preferably, the thermistor 11 is a thermistor transistor, and exemplarily, the thermistor transistor is a MOS transistor. Understandably, the MOS transistor can be an NMOS transistor or a PMOS transistor.

[0046] For example, the thermistor is an NMOS transistor, with its drain connected to a power supply, its source grounded, and its gate connected to a bias voltage source. When the ambient temperature changes, the thermistor's threshold voltage, gate-source voltage, or drain-source voltage changes accordingly. Therefore, the corresponding ambient temperature can be determined based on the thermistor's threshold voltage, gate-source voltage, or drain-source voltage. Understandably, this temperature simulation signal includes the thermistor's threshold voltage, gate-source voltage, or drain-source voltage.

[0047] As an example, the signal acquisition circuit 12 is connected to the thermistor 11, the charging current control circuit 2, and the discharging voltage control circuit 3 to acquire a temperature analog signal and output a temperature detection signal. Understandably, the signal acquisition circuit 12 includes a voltage acquisition circuit for acquiring the threshold voltage, gate-source voltage, or drain-source voltage of the thermistor. It should be noted that this voltage acquisition circuit can employ techniques known in the art, and no limitation is made herein.

[0048] In this embodiment, the temperature detection circuit 1 includes a thermistor 11 and a signal acquisition circuit 12. The thermistor 11 is used to output a temperature analog signal according to the ambient temperature. The signal acquisition circuit 12 is connected to the thermistor 11, the charging current control circuit 2 and the discharging voltage control circuit 3, and is used to acquire the temperature analog signal and output the temperature detection signal, thus realizing the ambient temperature detection. The circuit structure is simple and the cost is low.

[0049] In one embodiment, such as Figure 2 As shown, the charging current control circuit 2 includes a first operational amplifier 21, a second operational amplifier 22, and a current adjustment circuit 23. The first input terminal of the first operational amplifier 21 is connected to the temperature detection circuit 1, the second input terminal of the first operational amplifier 21 is connected to the first reference voltage terminal Vref1, and the output terminal of the first operational amplifier 21 is used to output a first voltage based on the temperature detection signal and the first reference voltage provided by the first reference voltage terminal Vref1. The first input terminal of the second operational amplifier 22 is connected to the output terminal of the first operational amplifier 21, the second input terminal of the second operational amplifier 22 is connected to the second reference voltage terminal Vref2, and the output terminal of the second operational amplifier 22 is used to output a second voltage based on the first voltage and the second reference voltage provided by the second reference voltage terminal Vref2. The input terminal of the current adjustment circuit 23 is connected to the external power supply VIN, the output terminal of the current adjustment circuit 23 is connected to the secondary battery cell 4, and the control terminal of the current adjustment circuit 23 is connected to the output terminal of the second operational amplifier 22, used to adjust the charging current of the secondary battery cell 4 according to the second voltage.

[0050] For example, the first reference voltage can be set according to the safe ambient temperature value. For instance, if the safe ambient temperature value is X, then the corresponding first reference voltage V1 is set. When the voltage value corresponding to the temperature detection signal output by the temperature detection circuit 1 is greater than the first reference voltage V1, it indicates that the ambient temperature exceeds the safe ambient temperature value X. At this time, the first operational amplifier 21 operates in the saturation region and outputs the first voltage. Understandably, this first voltage is the positive power supply voltage of the first operational amplifier 21.

[0051] For example, the second reference voltage can be set according to the positive power supply voltage of the first operational amplifier 21. For instance, the second reference voltage V2 is less than the positive power supply voltage of the first operational amplifier 21 and greater than the negative power supply voltage of the first operational amplifier 21. Understandably, when the first voltage is the positive power supply voltage of the first operational amplifier 21, the first voltage is greater than the second reference voltage, the second operational amplifier 22 operates in the saturation region, and the output second voltage is the positive power supply voltage of the second operational amplifier 22.

[0052] Exemplarily, when the second voltage is the positive power supply voltage of the second operational amplifier 22, the current adjustment circuit 23 reduces the charging current of the secondary battery cell 4. Conversely, when the second voltage is the negative power supply voltage of the second operational amplifier 22, the current adjustment circuit 23 increases the charging current of the secondary battery cell 4.

[0053] It should be noted that the specific values of the first reference voltage and the second reference voltage can be set according to actual experience.

[0054] In one embodiment, the current adjustment circuit 23 includes a first transistor 231; a first end of the first transistor 231 is connected to an external power supply VIN, a second end of the first transistor 231 is connected to the secondary battery cell 4, and a third end of the first transistor 231 is connected to an output end of the second operational amplifier 22.

[0055] Optionally, the first transistor 231 can be a MOS transistor or a bipolar transistor. In this example, the first transistor 231 is taken as a PMOS transistor for illustration. The first end of the first transistor 231 is the source electrode, the second end of the first transistor 231 is the drain electrode, and the third end of the first transistor 231 is the gate electrode. Exemplarily, when the voltage value corresponding to the temperature detection signal is not greater than the first reference voltage V1, it indicates that the ambient temperature is lower than the safe ambient temperature value X, the second operational amplifier 22 outputs a second voltage which is the negative power supply voltage VEE of the second operational amplifier 22, and the gate-source voltage VGS1 of the first transistor 231 is the negative power supply voltage VEE - the voltage Vin of the external power supply VIN; when the voltage value corresponding to the temperature detection signal is greater than the first reference voltage V1, it indicates that the ambient temperature exceeds the safe ambient temperature value X, the second operational amplifier 22 outputs a second voltage which is the positive power supply voltage Vcc of the second operational amplifier 22, the gate-source voltage VGS2 of the first transistor 231 is the positive power supply voltage Vcc - the voltage Vin of the external power supply VIN, and the gate-source voltage of the first transistor 231 increases, so that the on-current of the first transistor 231 decreases, and thus when the ambient temperature exceeds the safe ambient temperature value X, the charging current is reduced. Among them, VGS1 < VGS2 < Vt, where Vt is the threshold voltage for the first transistor 231 to conduct.

[0056] In this embodiment, the charging current of the secondary battery cell 4 can be adjusted through the first transistor 231, and the structure is simple and the cost is low.

[0057] In one embodiment, as Figure 2As shown, the charging current control circuit 2 also includes a third operational amplifier 24; the first input terminal of the third operational amplifier 24 is connected to the temperature detection circuit 1, the second input terminal of the third operational amplifier 24 is used to connect to the third reference voltage terminal Vref3, and the output terminal of the third operational amplifier 24 is connected to the control terminal of the current adjustment circuit 23, and is used to output a third voltage to the control terminal of the current adjustment circuit 23 according to the temperature detection signal and the third reference voltage provided by the third reference voltage terminal Vref3; the third reference voltage is greater than the first reference voltage.

[0058] For example, the third reference voltage can be set according to the over-temperature protection value. For instance, if the over-temperature protection value is Y, and Y is greater than the safe ambient temperature value X, then the corresponding third reference voltage V3 is set. When the voltage value corresponding to the temperature detection signal output by the temperature detection circuit 1 is greater than the third reference voltage V3, it indicates that the ambient temperature exceeds the over-temperature protection value Y. At this time, the third operational amplifier 24 operates in the saturation region and outputs the third voltage, which is understood to be the positive power supply voltage of the third operational amplifier 24. In this embodiment, by setting the positive power supply voltage of the third operational amplifier 24 to be greater than the voltage of the external power supply VIN, the first transistor 231 in the current adjustment circuit 23 can be turned off when the ambient temperature exceeds the over-temperature protection value Y, thereby achieving over-temperature protection and improving safety.

[0059] In one embodiment, the discharge voltage control circuit 3 includes a reference selection circuit 31 and a step-down circuit 32. The reference selection circuit 31 is connected to the temperature detection circuit 1 and is used to select a target reference voltage corresponding to the temperature detection signal according to the temperature detection signal. The step-down circuit 32 is connected to the reference selection circuit 31, the secondary battery cell 4 and the voltage output terminal VOUT and is used to output a discharge voltage corresponding to the target reference voltage according to the target reference voltage.

[0060] For example, the reference selection circuit 31 selects the corresponding target reference voltage based on the voltage magnitude corresponding to the temperature detection signal. For instance, when the voltage corresponding to the temperature detection signal is higher, a lower target reference voltage is selected, thereby enabling the step-down circuit 32 to further reduce the discharge voltage as the ambient temperature rises. Due to the reduced discharge voltage, when the secondary battery to dry battery is connected to a constant power load, the discharge current is forced to increase under the premise of constant power discharge, thereby triggering closed-loop control to limit the current increase. This ensures that the secondary battery to dry battery control chip will not be damaged and will not stop discharging, thus preventing the battery from running out of power and improving the secondary battery to dry battery range.

[0061] In one embodiment, the step-down circuit 32 is a switching step-down circuit.

[0062] For example, the switching buck circuit (not shown in the figure) includes a first PMOS transistor, a first NMOS transistor, a driving circuit, a first voltage divider circuit, a first comparator, a first inductor, and a first capacitor. The source of the first PMOS transistor is connected to the secondary battery cell 4, the drain of the first PMOS transistor is connected to the drain of the first NMOS transistor and the first terminal of the first inductor, the drain of the first NMOS transistor is grounded, the first terminal of the first inductor is connected to the first terminal of the first capacitor, the second terminal of the first capacitor is grounded, and the connection node between the first inductor and the first capacitor is used to output the discharge voltage; the first terminal of the first voltage divider circuit is connected to the connection node between the first inductor and the first capacitor, the second terminal of the first voltage divider circuit is grounded, the third terminal of the first voltage divider circuit is connected to the non-inverting input terminal of the first comparator, and the inverting input terminal of the first comparator is connected to the reference selection circuit 31 to receive the target reference voltage corresponding to the temperature detection signal output by the reference selection circuit 31; the output terminal of the first comparator is connected to the driving circuit, and the driving circuit is connected to the gate of the first PMOS transistor and the gate of the first NMOS transistor respectively. For example, when the ambient temperature is lower than the safe temperature, the voltage corresponding to the temperature detection signal is Vm1, and the corresponding target reference voltage is Va. When the ambient temperature is higher than the safe temperature, the voltage corresponding to the temperature detection signal is Vm2, and the corresponding target reference voltage is Vb. Vm1 is greater than Vm2, and Va is less than Vb. Thus, when the ambient temperature rises, by selecting different target reference voltages and using the driving circuit to alternately turn on the first PMOS transistor and the first NMOS transistor, in conjunction with the first inductor and the first capacitor, the discharge voltage can be reduced.

[0063] This embodiment provides a secondary battery to dry battery control chip, including the aforementioned secondary battery to dry battery conversion circuit.

[0064] The above-described embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model, and should all be included within the protection scope of this utility model.

Claims

1. A conversion circuit for converting a secondary battery to a dry cell battery, characterized in that, Includes a temperature detection circuit, a charging current control circuit, and a discharging voltage control circuit; The temperature detection circuit is used to detect the ambient temperature and output a temperature detection signal; The charging current control circuit is connected to the external power supply, the temperature detection circuit, and the secondary battery cell, and is used to adjust the charging current of the secondary battery cell according to the ambient temperature when the secondary battery cell is in the charging state. The discharge voltage control circuit is connected to the secondary battery cell, the temperature detection circuit, and the voltage output terminal, and is used to adjust the discharge voltage of the secondary battery cell according to the ambient temperature when the secondary battery cell is in a discharge state.

2. The conversion circuit for converting a secondary battery to a dry cell battery according to claim 1, characterized in that, The temperature detection circuit includes a thermistor and a signal acquisition circuit; The thermistor is used to output a temperature analog signal based on the ambient temperature; The signal acquisition circuit is connected to the thermistor, the charging current control circuit, and the discharging voltage control circuit, and is used to acquire the temperature analog signal and output the temperature detection signal.

3. The conversion circuit for converting a secondary battery to a dry cell battery according to claim 2, characterized in that, The thermistor includes a thermistor transistor or a thermistor resistor.

4. The conversion circuit for converting a secondary battery to a dry cell battery according to claim 1, characterized in that, The charging current control circuit includes a first operational amplifier, a second operational amplifier, and a current adjustment circuit; The first input terminal of the first operational amplifier is connected to the temperature detection circuit, the second input terminal of the first operational amplifier is used to connect to the first reference voltage terminal, and the output terminal of the first operational amplifier is used to output a first voltage according to the temperature detection signal and the first reference voltage provided by the first reference voltage terminal; The first input terminal of the second operational amplifier is connected to the output terminal of the first operational amplifier, the second input terminal of the second operational amplifier is connected to the second reference voltage terminal, and the output terminal of the second operational amplifier is used to output a second voltage according to the first voltage and the second reference voltage provided by the second reference voltage terminal; The input terminal of the current adjustment circuit is connected to the external power supply, the output terminal of the current adjustment circuit is connected to the secondary battery cell, and the control terminal of the current adjustment circuit is connected to the output terminal of the second operational amplifier, for adjusting the charging current of the secondary battery cell according to the second voltage.

5. The conversion circuit for converting a secondary battery to a dry cell battery according to claim 4, characterized in that, The current adjustment circuit includes a first transistor; The first terminal of the first transistor is connected to the external power supply, the second terminal of the first transistor is connected to the secondary battery cell, and the third terminal of the first transistor is connected to the output terminal of the second operational amplifier.

6. The conversion circuit for converting a secondary battery to a dry cell battery according to claim 5, characterized in that, The first transistor is a PMOS transistor, with its first terminal being the source, its second terminal being the drain, and its third terminal being the gate.

7. The conversion circuit for converting a secondary battery to a dry cell battery according to claim 4, characterized in that, The charging current control circuit also includes a third operational amplifier; The first input terminal of the third operational amplifier is connected to the temperature detection circuit, the second input terminal of the third operational amplifier is used to connect to the third reference voltage terminal, and the output terminal of the third operational amplifier is connected to the control terminal of the current adjustment circuit, and is used to output a third voltage to the control terminal of the current adjustment circuit according to the temperature detection signal and the third reference voltage provided by the third reference voltage terminal. The third reference voltage is greater than the first reference voltage.

8. The conversion circuit for converting a secondary battery to a dry cell battery according to claim 1, characterized in that, The discharge voltage control circuit includes a reference selection circuit and a step-down circuit; The reference selection circuit is connected to the temperature detection circuit and is used to select a target reference voltage corresponding to the temperature detection signal based on the temperature detection signal. The step-down circuit is connected to the reference selection circuit, the secondary battery cell, and the voltage output terminal, and is used to output a discharge voltage corresponding to the target reference voltage according to the target reference voltage.

9. The conversion circuit for converting a secondary battery to a dry cell battery according to claim 8, characterized in that, The step-down circuit is a switching step-down circuit.

10. A secondary battery to dry battery control chip, characterized in that, It includes a conversion circuit for converting a secondary battery to a dry cell as described in any one of claims 1 to 9.

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