Temperature detection circuit, battery pack and power device

Abstract

The utility model provides a temperature detection circuit, a battery pack and a power plant, the temperature detection circuit is used for detecting the temperature of a battery cell, the detection circuit comprises a temperature measurement module, a signal amplification module, a rectification module, a filtering module and an acquisition module, the temperature measurement module is connected with the signal amplification module, and the signal amplification module is connected with the rectification module. The temperature measuring module can measure the temperature of the battery cell and output a temperature signal; the signal amplification module is connected with the rectification module, and the signal amplification module can receive the temperature signal and output an amplified signal; the rectifier module is connected with the signal amplification module, and the rectifier module can rectify the amplified signal and output a rectified signal; the filtering module is connected with the rectification module, and the filtering module can receive the rectification signal and output a filtering signal; the acquisition module is connected with the filtering module, and the acquisition module can receive the filtering signal and output the temperature of the battery cell. The temperature detection circuit provided by the utility model can improve the use quality of the battery pack by optimizing the circuit structure.

Description

Technical Field

[0001] The utility model relates to the technical field of battery packs, and in particular to a temperature detection circuit. The utility model also relates to a battery pack provided with the temperature detection circuit, and a power device provided with the battery pack. Background Art

[0002] With the rapid development of new energy vehicles, the battery packs of new energy vehicles are small in size and high in internal density. The power source of new energy vehicles is a large number of module batteries. The charging and discharging of new energy power batteries during driving will be affected by temperature, and temperature changes will directly lead to changes in the internal resistance of the battery and the chemical rate of the battery pack.

[0003] The performance of the battery pack will also be affected by temperature. Too high or too low temperature will not only directly affect the internal resistance characteristics of the battery and change its charging and discharging efficiency, but also accelerate the rate of chemical reactions inside the battery, which may cause structural changes in battery materials and shorten the battery life. In addition, temperature changes in the battery pack may also cause thermal runaway of the battery pack, which will affect the safety of the battery pack and is not conducive to improving the quality of the battery pack. Utility Model Content

[0004] In view of this, the present invention aims to provide a temperature detection circuit, so as to improve the use quality of a battery pack by optimizing the circuit structure.

[0005] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0006] A temperature detection circuit is used for detecting the temperature of a battery cell. The detection circuit comprises: a temperature measurement module, a signal amplification module, a rectification module, a filtering module and a collection module;

[0007] The temperature measurement module is connected to the signal amplification module, and the temperature measurement module can measure the temperature of the battery cell and output an electrical signal;

[0008] The signal amplification module is connected to the rectification module, and the signal amplification module can receive the electrical signal and output an amplified signal;

[0009] The rectifying module is connected to the signal amplifying module, and the rectifying module is capable of rectifying the amplified signal and outputting a rectified signal;

[0010] The filtering module is connected to the rectifying module, and the filtering module is capable of receiving the rectifying signal and outputting a filtering signal;

[0011] The acquisition module is connected to the filter module, and the acquisition module can receive the filter signal and output the temperature of the battery cell.

[0012] Further, the temperature measurement module includes a thermistor, a DC power supply, a first capacitor, a second capacitor and a first inductor;

[0013] The thermistor is arranged on the battery core, and a first end of the thermistor is connected to the positive electrode of the DC power supply, a second end of the thermistor is connected to the negative electrode of the DC power supply, a first end of the first capacitor is commonly connected to the positive electrode of the DC power supply, a second end of the first capacitor and a first end of the second capacitor are commonly connected to the ground, and a second end of the second capacitor is commonly connected to the negative electrode of the DC power supply. A first end of the primary coil of the first inductor is connected to the positive electrode of the DC power supply, a second end of the primary coil of the first inductor is connected to the negative electrode of the DC power supply, and a secondary coil of the first inductor is connected to the input end of the signal amplification module.

[0014] Furthermore, the signal amplification module adopts a high input impedance amplification circuit, and the secondary coil is connected to the input end of the high input impedance amplification circuit.

[0015] Further, the high input impedance amplifier circuit includes a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, a first operational amplifier and a second operational amplifier;

[0016] A first end of the first resistor is connected to a first end of the secondary coil, a second end of the first resistor is connected to an inverting input end of the first operational amplifier, a first end of the second resistor is commonly connected to the first end of the secondary coil, a second end of the second resistor is connected to an output end of the second operational amplifier, a first end of the third resistor is connected to a non-inverting input end of the first operational amplifier, a second end of the third resistor is grounded, a first end of the fourth resistor is commonly connected to the output end of the second operational amplifier, a second end of the fourth resistor is connected to an inverting input end of the second operational amplifier, a first end of the fifth resistor is connected to a reverse input end of the second operational amplifier, a second end of the fifth resistor is connected to a first end of the sixth resistor, a second end of the sixth resistor is connected to an inverting input end of the first operational amplifier, a first end of the seventh resistor is connected to the non-inverting input end of the second operational amplifier, a second end of the seventh resistor is grounded, and an output end of the first operational amplifier is connected to the rectifier module.

[0017] Further, the rectifier module includes a first rectifier diode, a second rectifier diode and an eighth resistor;

[0018] The anode of the first rectifier diode is connected to the output end of the first operational amplifier, the cathode of the first rectifier diode is connected to the input end of the filter module, the anode of the second rectifier diode is connected to the output end of the first operational amplifier, the cathode of the second rectifier diode is connected to the input end of the filter module, the first end of the eighth resistor is connected to the output end of the first operational amplifier, and the second end of the eighth resistor is connected to the input end of the filter module.

[0019] Further, the filtering module includes a ninth resistor, a tenth resistor, a third capacitor and a fourth capacitor;

[0020] The first end of the ninth resistor is connected to the output end of the rectifier module, the second end of the ninth resistor is connected to the first end of the third capacitor, the first end of the tenth resistor is connected to the second end of the ninth resistor, the second end of the tenth resistor is connected to the signal input end of the acquisition module, the second end of the third capacitor is grounded, the first end of the fourth capacitor is connected to the second end of the tenth resistor, and the second end of the fourth capacitor is connected to the ground.

[0021] Furthermore, the acquisition module includes a voltage acquisition unit, and the voltage acquisition unit can acquire the voltage signal output by the filter module.

[0022] Compared with the prior art, the utility model has the following advantages:

[0023] The temperature detection circuit described in the utility model can measure the temperature of the battery cell through the temperature measuring module and convert it into an electrical signal. After the electrical signal is amplified by the signal amplification module, it is rectified by the rectifier module, filtered by the filtering module, and the filtered signal is output. The output filtered signal is collected by the acquisition module to output the temperature of the battery cell. By measuring the temperature of the battery cell, the temperature condition in the battery pack can be monitored, which is beneficial to prevent the battery pack from being damaged due to abnormal temperature in the battery pack, which is beneficial to improve the safety of the battery pack, and thus the quality of the battery pack.

[0024] By adopting thermistors, temperature signals can be better converted into electrical signals and transmitted to the signal amplification module through inductors. The structure is simple and convenient for design implementation.

[0025] By adopting a high input impedance amplifier circuit, tiny electrical signals can be amplified, which is beneficial to the amplification of the electrical signals after the thermistor changes, so that the temperature of the battery cell can be measured more accurately, which is beneficial to the design implementation.

[0026] The amplified signal can be rectified by the rectifier module, making the output rectified signal more regular, which is conducive to design implementation.

[0027] By setting the filter module, the interference of the rectified signal can be removed, making the output filtered signal more accurate, which is conducive to the acquisition module to collect a more accurate filtered signal.

[0028] The utility model also proposes a battery pack, in which the temperature detection circuit as described above is arranged. The utility model also proposes a power device, in which the battery pack as described above is arranged.

[0029] The battery pack and the power device described in the present invention have the same beneficial effects as the temperature detection circuit described above compared to the prior art, so they will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the accompanying drawings:

[0031] Figure 1 A circuit diagram of a temperature detection circuit according to an embodiment of the present utility model;

[0032] Description of reference numerals:

[0033] 10. Temperature measurement module; 20. Signal amplification module; 30. Rectification module; 40. Filter module. DETAILED DESCRIPTION

[0034] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0035] In the description of the present invention, it should be noted that if there are terms such as "upper", "lower", "inner", "outer" and the like indicating orientation or positional relationship, they are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, if there are terms such as "first" and "second", they are also used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0036] In addition, in the description of the present invention, unless otherwise clearly defined, the terms "installation", "connection", "connection" and "connector" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood in combination with specific circumstances.

[0037] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0038] Embodiment 1

[0039] The present embodiment relates to a temperature detection circuit to improve the safety of a battery pack.

[0040] In terms of overall structure, as shown in the figure, the temperature detection circuit in this embodiment is used for detecting the temperature of the battery cell, and the detection circuit includes: a temperature measurement module 10, a signal amplification module 20, a rectification module 30, a filtering module 40 and an acquisition module.

[0041] The temperature measurement module 10 is connected to the signal amplification module 20 , and the temperature measurement module 10 can measure the temperature of the battery cell and output an electrical signal.

[0042] The signal amplifying module 20 is connected to the rectifying module 30 , and the signal amplifying module 20 can receive an electrical signal and output an amplified signal.

[0043] The rectifying module 30 is connected to the signal amplifying module 20 , and the rectifying module 30 can rectify the amplified signal and output the rectified signal.

[0044] The filter module 40 is connected to the rectifier module 30 , and the filter module 40 can receive the rectifier signal and output the filter signal.

[0045] The acquisition module is connected to the filter module 40 , and the acquisition module can receive the filter signal and output the temperature of the battery cell.

[0046] As configured above, the temperature detection circuit in this embodiment can measure the temperature of the battery cell through the temperature measuring module 10 and convert it into an electrical signal. After the electrical signal is amplified by the signal amplification module 20, it is rectified by the rectifier module 30, and then filtered by the filter module 40 to output the filtered signal. The output filtered signal is collected by the acquisition module to output the temperature of the battery cell. By measuring the temperature of the battery cell, the temperature condition inside the battery pack can be monitored, which is beneficial to prevent damage to the battery pack due to abnormal temperature inside the battery pack, and is beneficial to improving the safety of the battery pack, thereby improving the quality of the battery pack.

[0047] Specifically, in this embodiment, as an exemplary structure, in order to better measure the temperature of the battery cell, the temperature measurement module 10 of the temperature detection circuit in this embodiment includes a thermistor NTC, a DC power supply, a first capacitor C1, a second capacitor C2 and a first inductor L.

[0048] Specifically, in the present embodiment, the thermistor NTC is arranged on the battery core, and the first end of the thermistor NTC is connected to the positive electrode of the DC power supply, the second end of the thermistor NTC is connected to the negative electrode of the DC power supply, the first end of the first capacitor C1 is commonly connected to the positive electrode of the DC power supply, the second end of the first capacitor C1 and the first end of the second capacitor C2 are commonly connected to the ground, and the second end of the second capacitor C2 is commonly connected to the negative electrode of the DC power supply. The first end of the primary coil of the first inductor L is connected to the positive electrode of the DC power supply, the second end of the primary coil of the first inductor L is connected to the negative electrode of the DC power supply, and the secondary coil of the first inductor L is connected to the input end of the signal amplification module 20. By adopting the thermistor NTC, the temperature signal can be better converted into an electrical signal and transmitted to the signal amplification module 20 through the inductor. The structure is simple and convenient for design and implementation.

[0049] In order to better amplify the electrical signal of the temperature measurement module 10, the signal amplification module 20 of the temperature detection circuit in this embodiment adopts a high input impedance amplifier circuit, and the secondary coil of the first inductor L is connected to the input end of the high input impedance amplifier circuit.

[0050] Specifically, the high input impedance amplifier circuit in this embodiment includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a first operational amplifier N1 and a second operational amplifier N2.

[0051] Wherein, a first end of the first resistor R1 is connected to a first end of the secondary coil, a second end of the first resistor R1 is connected to an inverting input end of the first operational amplifier N1, a first end of the second resistor R2 is connected to the first end of the secondary coil, a second end of the second resistor R2 is connected to an output end of the second operational amplifier N2, a first end of the third resistor R3 is connected to a non-inverting input end of the first operational amplifier N1, a second end of the third resistor R3 is grounded, a first end of the fourth resistor R4 is connected to the output end of the second operational amplifier N2, a second end of the fourth resistor R4 is connected to an inverting input end of the second operational amplifier N2, a fifth resistor R5 is connected to a first end of the second resistor R6, and a fifth resistor R7 is connected to a second end of the third resistor R8. The first end is connected to the reverse input end of the second operational amplifier N2, the second end of the fifth resistor R5 is connected to the first end of the sixth resistor R6, the second end of the sixth resistor R6 is connected to the inverting input end of the first operational amplifier N1, the first end of the seventh resistor R7 is connected to the non-inverting input end of the second operational amplifier N2, the second end of the seventh resistor R7 is grounded, and the output end of the first operational amplifier N1 is connected to the rectifier module 30. By adopting a high input impedance amplifier circuit, tiny electrical signals can be amplified, which is beneficial to the amplification of the electrical signals after the thermistor NTC changes, so that the temperature of the battery cell can be measured more accurately, which is beneficial to the design implementation.

[0052] In order to better rectify the amplified signal, the rectifying module 30 of the temperature detection circuit in this embodiment includes a first rectifying diode D1 , a second rectifying diode D2 and an eighth resistor R8 .

[0053] Specifically, the anode of the first rectifier diode D1 is connected to the output end of the first operational amplifier N1, the cathode of the first rectifier diode D1 is connected to the input end of the filter module 40, the anode of the second rectifier diode D2 is connected to the output end of the first operational amplifier N1, the cathode of the second rectifier diode D2 is connected to the input end of the filter module 40, the first end of the eighth resistor R8 is connected to the output end of the first operational amplifier N1, and the second end of the eighth resistor R8 is connected to the input end of the filter module 40. The amplified signal can be rectified through the rectifier module 30, so that the output rectified signal is more regular, which is conducive to design implementation.

[0054] In order to better filter out interference waves, the filter module 40 of the temperature detection circuit in this embodiment includes a ninth resistor R9, a tenth resistor R10, a third capacitor C3 and a fourth capacitor C4.

[0055] Among them, the first end of the ninth resistor R9 is connected to the output end of the rectifier module 30, the second end of the ninth resistor R9 is connected to the first end of the third capacitor C3, the first end of the tenth resistor R10 is connected to the second end of the ninth resistor R9, the second end of the tenth resistor R10 is connected to the signal input end of the acquisition module, the second end of the third capacitor C3 is grounded, the first end of the fourth capacitor C4 is connected to the second end of the tenth resistor R10, and the second end of the fourth capacitor C4 is connected to the ground. Through the setting of the filtering module 40, the interference of the rectified signal can be removed, so that the output filtered signal is more accurate, which is conducive to the acquisition module to collect a more accurate filtered signal.

[0056] In order to better collect the filtered signal and output the temperature, the collection module of the temperature detection circuit in this embodiment includes a voltage collection unit, and the voltage collection unit can collect the voltage signal output by the filter module 40.

[0057] Specifically, the acquisition module in this embodiment can be connected to the BMS of the battery pack, and the voltage signal collected by the acquisition module can be monitored through the BMS. When the collected voltage signal reaches a preset threshold, it can be proved that the temperature of the battery cell detected by the temperature detection circuit is abnormal, so that the abnormal temperature situation can be detected in time, which is conducive to handling the abnormal temperature in the battery pack.

[0058] The temperature detection circuit in the present embodiment measures temperature through a thermistor NTC, amplifies the signal through a signal amplification module 20, rectifies the signal through a rectifier module 30, filters out interference waves in the rectified signal through a filter module 40, collects the output voltage signal through an acquisition module, and processes the temperature inside the battery pack through the BMS module of the battery pack, thereby facilitating the detection of abnormal temperature of the battery cell, helping to improve the safety of the battery pack, and being able to improve the quality of the battery pack.

[0059] Embodiment 2

[0060] This embodiment relates to a battery pack, in which the temperature detection circuit in the first embodiment is provided.

[0061] The battery pack in this embodiment can monitor the temperature of the battery cell through the setting of the temperature detection circuit in Example 1, which helps to monitor the temperature of the battery cell, so that the temperature abnormality of the battery cell can be detected in time, thereby helping to improve the safety of the battery pack.

[0062] Embodiment 3

[0063] This embodiment relates to a power device, in which the battery pack in the second embodiment is provided.

[0064] The power device in this embodiment, through the setting of the battery pack in the second embodiment, can timely detect the temperature abnormality in the battery pack, which is beneficial to the processing of the battery pack temperature abnormality, thereby facilitating the improvement of the safety of the power device.

[0065] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A temperature detection circuit for detecting the temperature of a battery cell, characterized in that: The detection circuit includes: a temperature measurement module, a signal amplification module, a rectification module, a filtering module and a collection module; The temperature measurement module is connected to the signal amplification module, and the temperature measurement module can measure the temperature of the battery cell and output an electrical signal; The signal amplification module is connected to the rectification module, and the signal amplification module can receive the electrical signal and output an amplified signal; The rectifying module is connected to the signal amplifying module, and the rectifying module is capable of rectifying the amplified signal and outputting a rectified signal; The filtering module is connected to the rectifying module, and the filtering module is capable of receiving the rectifying signal and outputting a filtering signal; The acquisition module is connected to the filter module, and the acquisition module can receive the filter signal and output the temperature of the battery cell.

2. The temperature detection circuit according to claim 1, characterized in that: The temperature measurement module includes a thermistor, a DC power supply, a first capacitor, a second capacitor and a first inductor; The thermistor is arranged on the battery core, and a first end of the thermistor is connected to the positive electrode of the DC power supply, a second end of the thermistor is connected to the negative electrode of the DC power supply, a first end of the first capacitor is commonly connected to the positive electrode of the DC power supply, a second end of the first capacitor and a first end of the second capacitor are commonly connected to the ground, and a second end of the second capacitor is commonly connected to the negative electrode of the DC power supply. A first end of the primary coil of the first inductor is connected to the positive electrode of the DC power supply, a second end of the primary coil of the first inductor is connected to the negative electrode of the DC power supply, and a secondary coil of the first inductor is connected to the input end of the signal amplification module.

3. The temperature detection circuit according to claim 2, characterized in that: The signal amplification module adopts a high input impedance amplification circuit, and the secondary coil is connected to the input end of the high input impedance amplification circuit.

4. The temperature detection circuit according to claim 3, characterized in that: The high input impedance amplifier circuit comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, a first operational amplifier and a second operational amplifier; A first end of the first resistor is connected to a first end of the secondary coil, a second end of the first resistor is connected to an inverting input end of the first operational amplifier, a first end of the second resistor is commonly connected to the first end of the secondary coil, a second end of the second resistor is connected to an output end of the second operational amplifier, a first end of the third resistor is connected to a non-inverting input end of the first operational amplifier, a second end of the third resistor is grounded, a first end of the fourth resistor is commonly connected to the output end of the second operational amplifier, a second end of the fourth resistor is connected to an inverting input end of the second operational amplifier, a first end of the fifth resistor is connected to a reverse input end of the second operational amplifier, a second end of the fifth resistor is connected to a first end of the sixth resistor, a second end of the sixth resistor is connected to an inverting input end of the first operational amplifier, a first end of the seventh resistor is connected to the non-inverting input end of the second operational amplifier, a second end of the seventh resistor is grounded, and an output end of the first operational amplifier is connected to the rectifier module.

5. The temperature detection circuit according to claim 4, characterized in that: The rectifier module includes a first rectifier diode, a second rectifier diode and an eighth resistor; The anode of the first rectifier diode is connected to the output end of the first operational amplifier, the cathode of the first rectifier diode is connected to the input end of the filter module, the anode of the second rectifier diode is connected to the output end of the first operational amplifier, the cathode of the second rectifier diode is connected to the input end of the filter module, the first end of the eighth resistor is connected to the output end of the first operational amplifier, and the second end of the eighth resistor is connected to the input end of the filter module.

6. The temperature detection circuit according to claim 5, characterized in that: The filtering module includes a ninth resistor, a tenth resistor, a third capacitor and a fourth capacitor; The first end of the ninth resistor is connected to the output end of the rectifier module, the second end of the ninth resistor is connected to the first end of the third capacitor, the first end of the tenth resistor is connected to the second end of the ninth resistor, the second end of the tenth resistor is connected to the signal input end of the acquisition module, the second end of the third capacitor is grounded, the first end of the fourth capacitor is connected to the second end of the tenth resistor, and the second end of the fourth capacitor is connected to the ground.

7. The temperature detection circuit according to claim 6, characterized in that: The acquisition module includes a voltage acquisition unit, and the voltage acquisition unit can acquire the voltage signal output by the filter module.

8. A battery pack, characterized in that: The battery pack is provided with a temperature detection circuit as described in any one of claims 1-7.

9. A power device, characterized in that: The power device is provided with a battery pack as claimed in claim 8.

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