Radio frequency tag chip, radio frequency read-write chip, temperature measurement system and battery system

Abstract

The invention provides a radio frequency tag chip, a radio frequency read-write chip, a temperature measurement system and a battery system. The passive radio frequency tag chip can be attached to the surface of a detection object, and comprises a temperature sensing circuit which is used for sensing the surface temperature of the detection object to obtain temperature sensing data; and the energy acquisition circuit can acquire energy from the radio-frequency electromagnetic waves so as to at least supply power to the temperature sensing circuit.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of temperature detection, and particularly relates to a radio frequency tag chip, a radio frequency read-write chip, a temperature measurement system and a battery system. BACKGROUND

[0002] In the safety detection of a battery management system (BMS), battery temperature monitoring is a key link to ensure the stable operation of a battery pack. A battery pack is composed of a large number of battery cells through series and parallel connection. If the temperature anomaly of a single battery cell is not monitored in time, it may cause thermal runaway and spread to the entire module, so it is crucial to realize accurate temperature detection at the battery cell level.

[0003] In the prior art, the battery cell and the module, and the module and the BMS host are connected through wires to transmit signals and power supply. This method has inherent defects: not only increases the weight and cost of the battery pack, but also occupies internal space, and is prone to low production and maintenance efficiency due to connector failure or complex wiring, affecting system reliability.

[0004] To solve the problem of wired connection, related wireless improvement schemes change the communication between the module and the BMS host to a wireless mode, which reduces part of the wiring harness, but the battery cell temperature detection still needs to be arranged through a wired temperature sensor, and cannot realize real wireless temperature measurement at the battery cell level. There is also a battery cell level monitoring technology that needs to use a wired auxiliary structure to realize data transmission, and the monitoring module needs to take power from the battery, which has the problems of insufficient installation flexibility and affected detection accuracy.

[0005] In summary, the prior art cannot simultaneously realize accurate temperature measurement, wireless transmission and flexible installation at the battery cell level, and there is still obvious technical improvement space. SUMMARY

[0006] The present disclosure provides a radio frequency tag chip, a radio frequency read-write chip, a temperature measurement system and a battery system.

[0007] According to one aspect of the present disclosure, the present disclosure provides a passive radio frequency tag chip capable of being attached to the surface of a detection object, comprising: a temperature sensing circuit, configured to sense the surface temperature of the detection object and obtain temperature sensing data; an energy acquisition circuit, configured to acquire energy from a radio frequency electromagnetic wave to at least power the temperature sensing circuit.

[0008] According to the passive radio frequency tag chip of at least one embodiment of the present disclosure, the passive radio frequency tag chip further comprises: a first antenna, configured to receive the radio frequency electromagnetic wave; A demodulation circuit connected with the first antenna, configured to demodulate radio frequency electromagnetic waves received by the first antenna, and demodulate control instructions carried in the radio frequency electromagnetic waves; A modulation circuit connected with the first antenna, configured to send a modulation signal containing the temperature sensing data via the first antenna.

[0009] According to the passive radio frequency tag chip of at least one embodiment of the present disclosure, the energy acquisition circuit comprises a rectifier, a limiter and a voltage stabilizer connected in sequence; the rectifier is connected with the first antenna, configured to convert radio frequency electromagnetic waves received by the first antenna into direct current electric energy; the limiter is configured to limit the voltage of the direct current electric energy to obtain a voltage signal after limiting; and the voltage stabilizer is configured to convert the voltage signal after limiting into a supply voltage.

[0010] According to the passive radio frequency tag chip of at least one embodiment of the present disclosure, the passive radio frequency tag chip further comprises a voltage reference module, a first oscillator, a power-on reset module and a digital baseband signal processing module; the voltage reference module is connected with the voltage stabilizer, configured to provide a stable reference voltage based on the supply voltage; the first oscillator is connected with the voltage reference module, configured to generate a clock signal based on the reference voltage; the power-on reset module is connected with the voltage stabilizer and the digital baseband signal processing module respectively, configured to monitor the change of the supply voltage, and when the supply voltage rises and reaches a preset working threshold, output a reset signal to the digital baseband signal processing module to reset the digital baseband signal processing module and start working; the temperature sensing circuit is connected between the voltage reference module and the digital baseband signal processing module, and the temperature sensing circuit performs temperature sensing based on the reference voltage provided by the voltage reference module, and sends the temperature sensing data to the digital baseband signal processing module; the digital baseband signal processing module encodes the temperature sensing data, and transmits the encoded temperature sensing data to the modulation circuit.

[0011] According to the passive radio frequency tag chip of at least one embodiment of the present disclosure, the temperature sensing circuit is a digital temperature sensor.

[0012] According to the passive radio frequency tag chip of at least one embodiment of the present disclosure, the rectifier comprises a single-stage alternating current rectification circuit; The single-stage alternating current rectification circuit comprises a first NMOS tube, a second NMOS tube, a first PMOS tube, a second PMOS tube, a first capacitor and a second capacitor; The drains of the two NMOS tubes are connected with each other as a common drain of NMOS tubes; and the drains of the two PMOS tubes are connected with each other as a common drain of PMOS tubes. The source of the first NMOS tube is connected with the source of the first PMOS tube as a first common source end; The source of the second NMOS tube is connected with the source of the second PMOS tube as a second common source end; The gate of the first NMOS tube is connected with the gate of the first PMOS tube as a first common gate end, and the first common gate end is connected with the second common source end; The gate of the second NMOS tube is connected with the gate of the second PMOS tube as a second common gate end, and the second common gate end is connected with the first common source end; The first capacitor is connected between the first common source end and an RFN end, and the second capacitor is connected between the second common source end and an RFP end; The RFP end is a radio frequency positive input end, used for being connected with a first output end of the first antenna to receive a radio frequency electromagnetic wave positive phase signal transmitted by the first antenna; The RFN end is a radio frequency negative input end, used for being connected with a second output end of the first antenna to receive a radio frequency electromagnetic wave negative phase signal transmitted by the first antenna; The first capacitor is used for coupling the negative phase signal received by the RFN end to the first common source end, and the second capacitor is used for coupling the positive phase signal received by the RFP end to the second common source end, so that a differential radio frequency signal enters the single-stage alternating current rectifier circuit and is converted into a direct current voltage signal through rectification.

[0013] According to at least one embodiment of the present disclosure, the rectifier includes at least one single-stage alternating current rectifier circuit; When the rectifier includes one single-stage alternating current rectifier circuit, the common drain end of the NMOS tube is grounded, and the common drain end of the PMOS tube is used as a direct current output end of the rectifier; When the rectifier includes a plurality of single-stage alternating current rectifier circuits, the plurality of single-stage alternating current rectifier circuits are connected in cascade; The cascade connection mode is as follows: For two adjacent single-stage alternating current rectifier circuits, the common drain end of the PMOS tube of a previous single-stage alternating current rectifier circuit is connected with the common drain end of the NMOS tube of a subsequent single-stage alternating current rectifier circuit; The common drain end of the NMOS tube of a first single-stage alternating current rectifier circuit in the rectifier is grounded, and the common drain end of the PMOS tube of a last single-stage alternating current rectifier circuit is used as a direct current output end of the rectifier; The direct current output end is connected with the limiter.

[0014] According to the passive radio frequency tag chip of at least one embodiment of the present disclosure, the temperature sensing circuit comprises a temperature sensing diode, a current source, a voltage follower, a ring oscillator and a counter; the current source is connected to the temperature sensing diode, for providing a bias current to the temperature sensing diode; the temperature sensing diode is used for sensing the surface temperature of the detection object and converting the temperature change into a voltage change; the voltage follower is connected to the temperature sensing diode, for tracking the voltage change on the temperature sensing diode and outputting a follow-up voltage to drive the ring oscillator; the ring oscillator is connected to the voltage follower, for converting the change of the follow-up voltage into a frequency change of a high-frequency oscillation clock signal and outputting the high-frequency oscillation clock signal; the clock signal input end of the counter is connected to the high-frequency oscillation clock signal, and the enable end of the counter is connected to the low-frequency clock signal generated by the first oscillator, so that the counter is enabled to count the high-frequency oscillation clock signal in the time period when the low-frequency clock signal is high, and a count output value is obtained, which is used as the temperature sensing data.

[0015] According to the passive radio frequency tag chip of at least one embodiment of the present disclosure, the temperature sensing circuit is connected to the voltage reference module, and the voltage reference module provides a reference voltage for the temperature sensing circuit to support the biasing of the temperature sensing diode and the tracking operation of the voltage follower; the output end of the counter is connected to the digital baseband signal processing module, for sending the count output value as temperature sensing data to the digital baseband signal processing module for encoding processing.

[0016] According to the passive radio frequency tag chip of at least one embodiment of the present disclosure, the ring oscillator comprises a plurality of inverters, and the plurality of inverters are arranged in an odd number of series; the inverter comprises an input end, an output end, a ground end and a power supply end; the power supply end of each inverter is connected to the output end of the voltage follower to receive the follow-up voltage; the ground end of each inverter is grounded; in adjacent two inverters, the output end of the former inverter is connected to the input end of the latter inverter; the input end of the first inverter is connected to the output end of the last inverter to form a closed-loop oscillation structure; the output end of the last inverter outputs the high-frequency oscillation clock signal and is connected to the clock signal input end of the counter; the ring oscillator adjusts the frequency of the high-frequency oscillation clock signal through the change of the follow-up voltage.

[0017] According to the passive radio frequency tag chip of at least one embodiment of the present disclosure, the detection object is a battery core or a single battery, and the battery core or the single battery has a battery tab; The passive radio frequency tag chip is attached close to the position of the battery tab of the battery core or the single battery; The first antenna is a coupling coil structure, and is attached to a surface of the battery cell or the single battery.

[0018] According to at least one embodiment of the present disclosure, the detection object is a battery cell or a single battery, and the battery cell or the single battery does not have a battery tab. The passive radio frequency tag chip is arranged in a middle region of the first antenna and is arranged integrally with the first antenna. The first antenna is a coupling coil structure, and is attached to a surface of the battery cell or the single battery.

[0019] According to another aspect of the present disclosure, a radio frequency read-write chip is provided, comprising: A transceiving unit is configured to transmit a radio frequency electromagnetic wave carrying an instruction and receive a return signal returned by the passive radio frequency tag chip and containing temperature sensing data. A carrier generating unit is configured to generate a radio frequency carrier. A quadrature mixing receiving unit is connected between the transceiving unit and the carrier generating unit, and is configured to perform quadrature mixing processing on the return signal and the radio frequency carrier to obtain an intermediate frequency signal. A double-path demodulation unit is connected to the quadrature mixing receiving unit, and is configured to perform double-path demodulation processing on the intermediate frequency signal to obtain a digital signal corresponding to the temperature sensing data. A digital processing unit is connected to the double-path demodulation unit, and is configured to perform decoding processing on the digital signal to obtain temperature sensing data corresponding to the digital signal. The passive radio frequency tag chip is the passive radio frequency tag chip according to any one of the embodiments of the present disclosure.

[0020] According to at least one embodiment of the present disclosure, the digital processing unit is further configured to generate a control instruction for controlling the passive radio frequency tag chip. The radio frequency read-write chip further comprises: A modulation transmitting unit is connected between the digital processing unit and the carrier generating unit, and is configured to modulate the control instruction onto the radio frequency carrier, amplify the power of the radio frequency carrier, and transmit the radio frequency carrier through the transceiving unit.

[0021] According to at least one embodiment of the present disclosure, the transceiving unit comprises a second antenna and a transceiving switch. The transceiving switch is configured to switch the working mode of the second antenna: In a transmitting mode, the modulation transmitting unit is connected to the second antenna, and in a receiving mode, the second antenna is connected to the quadrature mixing receiving unit.

[0022] According to the radio frequency read-write chip of at least one embodiment of the present disclosure, the carrier generating unit is a radio frequency carrier generator configured to generate I and Q orthogonal radio frequency carriers.

[0023] According to the radio frequency read-write chip of at least one embodiment of the present disclosure, the quadrature mixing receiving unit comprises a first mixer and a second mixer. The first mixer is connected to the I output end of the carrier generating unit and configured to mix the return signal with the I orthogonal radio frequency carrier to obtain an I intermediate frequency signal. The second mixer is connected to the Q output end of the carrier generating unit and configured to mix the return signal with the Q orthogonal radio frequency carrier to obtain a Q intermediate frequency signal.

[0024] According to the radio frequency read-write chip of at least one embodiment of the present disclosure, the dual-channel demodulation unit comprises a first demodulation path corresponding to the I intermediate frequency signal and a second demodulation path corresponding to the Q intermediate frequency signal. The two demodulation paths work in parallel and are configured to process the in-phase component and the quadrature component of the intermediate frequency signal, respectively.

[0025] According to the radio frequency read-write chip of at least one embodiment of the present disclosure, each demodulation path comprises a filtering module, an amplifying module, a gain adjusting module, and an analog-to-digital conversion module; the filtering module is configured to filter signal noise and high-frequency noise; the amplifying module is configured to enhance signal strength; the gain adjusting module is configured to dynamically adjust signal gain; and the analog-to-digital conversion module is configured to convert analog signals into digital signals.

[0026] According to the radio frequency read-write chip of at least one embodiment of the present disclosure, the filtering module comprises a band-pass filter and a low-pass filter. The band-pass filter is configured to filter signal noise, and the low-pass filter is configured to filter high-frequency noise.

[0027] According to the radio frequency read-write chip of at least one embodiment of the present disclosure, the amplifying module is an amplifier, the gain adjusting module is a variable gain amplifier, and the analog-to-digital conversion module is an analog-to-digital converter.

[0028] According to the radio frequency read-write chip of at least one embodiment of the present disclosure, the digital processing unit comprises a decoding circuit configured to decode the digital signals to analyze temperature sensing data in the return signal.

[0029] According to the radio frequency read-write chip of at least one embodiment of the present disclosure, the digital processing unit is further configured to perform round-robin read-write control on a plurality of passive radio frequency tag chips based on an anti-collision protocol and generate a control instruction for controlling the passive radio frequency tag chips.

[0030] According to yet another aspect of the present disclosure, a wireless temperature measurement system is provided, comprising: a plurality of passive radio frequency tag chips, each of which is attached to a surface of a battery cell or a battery monomer; a radio frequency read-write chip, which transmits radio frequency electromagnetic waves with the passive radio frequency tag chips wirelessly; The radio frequency electromagnetic waves emitted by the radio frequency read-write chip serve as the energy source for the passive radio frequency tag chips.

[0031] According to the wireless temperature measurement system of at least one embodiment of the present disclosure, the radio frequency read-write chip is arranged on a battery module, and the radio frequency read-write chip on the battery module is used to transmit radio frequency electromagnetic waves with the passive radio frequency tag chips on each battery cell or battery monomer in the battery module wirelessly.

[0032] According to the wireless temperature measurement system of at least one embodiment of the present disclosure, the number of radio frequency read-write chips is multiple; One radio frequency read-write chip is arranged on a battery pack, and the battery pack includes a plurality of battery modules; Each battery module is arranged with one radio frequency read-write chip; The passive radio frequency tag chips transmit radio frequency electromagnetic waves with the radio frequency read-write chips on the corresponding battery modules wirelessly, and / or the passive radio frequency tag chips transmit radio frequency electromagnetic waves with the radio frequency read-write chip on the battery pack wirelessly.

[0033] According to the wireless temperature measurement system of at least one embodiment of the present disclosure, further comprising: an analog front-end chip, which is used to detect the voltage and / or current of a plurality of series-connected battery cells in a battery module and transmit the detection results to the radio frequency read-write chip of the battery module.

[0034] According to yet another aspect of the present disclosure, a battery system is provided, comprising: a battery device, which is a battery module or a battery pack including a plurality of battery modules; and a wireless temperature measurement system of any one embodiment of the present disclosure, which is used to measure the temperature of the battery cells or battery monomers in the battery device wirelessly. BRIEF DESCRIPTION OF DRAWINGS

[0035] The accompanying drawings illustrate exemplary embodiments of the present disclosure and together with the description, explain the principles of the present disclosure, in which the drawings are included to provide further understanding of the present disclosure and are incorporated in and constitute a part of this specification.

[0036] Figure 1 is a structural schematic diagram of a passive radio frequency tag chip of one embodiment of the present disclosure.

[0037] Figure 2 is a structural schematic diagram of a passive radio frequency tag chip of another embodiment of the present disclosure.

[0038] Figure 3 is a structural schematic diagram of a passive radio frequency tag chip of another embodiment of the present disclosure.

[0039] Figure 4 is a structural schematic diagram of a rectifier of one embodiment of the present disclosure.

[0040] Figure 5 is a structural schematic diagram of a temperature sensing circuit of one embodiment of the present disclosure.

[0041] Figure 6 is a schematic diagram of a tag chip adopted by a battery core without a tab of the present disclosure.

[0042] Figure 7 is a schematic diagram of a tag chip adopted by a battery core with a tab of the present disclosure.

[0043] Figure 8 is a structural schematic diagram of a radio frequency read-write chip of one embodiment of the present disclosure.

[0044] Figure 9 is a structural schematic diagram of a radio frequency read-write chip of another embodiment of the present disclosure.

[0045] Figure 10 is a structural diagram of a radio frequency read-write chip of one preferred embodiment of the present disclosure.

[0046] Figure 11 is a structural schematic diagram of a wireless temperature measurement system of one embodiment of the present disclosure.

[0047] Figure 12 is a structural schematic diagram of a battery system of one embodiment of the present disclosure. DETAILED DESCRIPTION

[0048] The present disclosure will be described in further detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the related content, and not to limit the present disclosure. In addition, it should be noted that only parts related to the present disclosure are shown in the drawings for ease of description.

[0049] It should be noted that the embodiments in the present disclosure and the features in the embodiments can be combined with each other without conflict. The technical solutions of the present disclosure will be described in detail below with reference to the drawings and in combination with the embodiments.

[0050] Unless otherwise stated, the exemplary implementations / examples will be understood to provide exemplary features of various details that can be implemented in practice to embody the inventive concepts of the present disclosure. Accordingly, unless otherwise stated, features of the various implementations / examples can additionally be combined, separated, interchanged, and / or rearranged, without departing from the inventive concepts of the present disclosure.

[0051] The use of cross-hatching and / or shading in the drawings is generally used to indicate different regions within the same component and is not intended to indicate specific materials, material properties, dimensions, ratios, etc. Moreover, the use of same reference numerals in different figures indicates similar and / or identical components. In the drawings, the depicted exemplary embodiments can be somewhat simplified for the sake of illustration.

[0052] When a component is referred to as being “on” or “over” another component, “connected to” or “coupled to” another component, it can be directly on, directly connected to, or directly coupled to the other component, or intervening components can be present. However, when a component is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another component, there are no intervening components present. The term “connected” can refer to physical or electrical connection, with or without intervening components.

[0053] For descriptive purposes, the present disclosure can use spatial or relative terms, such as “below,” “lower,” “lowermost,” “above,” “upper,” “uppermost,” “vertical,” “horizontal,” and the like, to describe the relationship between one component and another component as the drawings can appear. Unless otherwise stated as used in the attachment, the spatial and / or relative terms are intended to encompass different orientations of the device in use, operation, and / or manufacture in addition to the orientation depicted in the drawings. For example, if the device in the drawings is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the exemplary term “below” can encompass both an orientation of above and below. Moreover, the device can be otherwise oriented (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0054] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Furthermore, to the extent that the terms "comprise," "have," "contain," and / or "include" and variations thereof are used herein, such terms are intended to be open-ended terms that also mean "consist of." Also, note that, as used herein, the terms "substantially," "approximately," and other similar terms are used as synonyms for "about," and are used to allow for a level of deviation expected to make the term "patentable" under patent law as interpreted by the United States Patent and Trademark Office. Note, however, that specific embodiments can have different tolerances depending on the implementation or exact end use of that embodiment.

[0055] Figure 1 is a structural schematic block diagram of a passive radio frequency tag chip of one embodiment of the present disclosure.

[0056] Referring to Figure 1 In some embodiments of the present disclosure, the passive radio frequency tag chip of the present disclosure, which can be attached to the surface of a detection object, comprises: a temperature sensing circuit, configured to sense the surface temperature of the detection object and obtain temperature sensing data; an energy acquisition circuit, configured to acquire energy from radio frequency electromagnetic waves to at least power the temperature sensing circuit.

[0057] Based on the passive radio frequency tag chip of the present disclosure, power is not required to be taken from the detection object, and the chip is powered passively by radio frequency electromagnetic waves, which significantly reduces the power consumption of the chip, avoids the influence of self-heating on temperature measurement accuracy, realizes accurate temperature sensing of the detection object, and is suitable for scenarios such as battery cores that have high requirements for temperature measurement accuracy.

[0058] Figure 2 is a structural schematic block diagram of a passive radio frequency tag chip of another embodiment of the present disclosure.

[0059] Referring to Figure 2 In some preferred embodiments of the present disclosure, based on Figure 1 the passive radio frequency tag chip of the present disclosure further comprises: a first antenna, configured to receive the radio frequency electromagnetic waves; a demodulation circuit, connected to the first antenna, configured to demodulate the radio frequency electromagnetic waves received by the first antenna, and demodulate the control instructions carried in the radio frequency electromagnetic waves; A modulation circuit is connected with the first antenna and sends a modulated signal containing the temperature sensing data via the first antenna.

[0060] It should be understood that in other embodiments, the first antenna can also not be part of the passive radio frequency tag chip.

[0061] The present embodiment realizes the transceiving of radio frequency signals through the first antenna, the demodulation circuit accurately analyzes the control instructions (such as the control instructions sent by the radio frequency read-write chip described below), and the modulation circuit completes the signal loading of the temperature data. The three work together to realize wireless communication, without the need for wired connection, reducing installation complexity and potential failure, and improving the layout flexibility of the chip in the battery pack.

[0062] Figure 3 is a structural schematic diagram of a passive radio frequency tag chip of still another embodiment of the present disclosure. It should be noted that, Figure 3 The structure shown is for detailed description of the passive radio frequency tag chip of the present disclosure and should not be understood as a limitation on the following technical solutions of the present disclosure.

[0063] Reference Figure 3 In the preferred embodiment of the present disclosure, the energy acquisition circuit includes a rectifier, a limiter, and a voltage stabilizer connected in sequence; The rectifier is connected with the first antenna and is used to convert the radio frequency electromagnetic waves received by the first antenna into direct current electric energy; The limiter is used to clamp and limit the voltage of the direct current electric energy to obtain a voltage signal after amplitude limiting; The voltage stabilizer is used to convert the voltage signal after amplitude limiting into a supply voltage (VDD).

[0064] In the present embodiment, the rectifier realizes the conversion of radio frequency alternating current signals into direct current electric energy, the limiter suppresses overvoltage impact, and the voltage stabilizer outputs a stable supply voltage. The three-stage circuit cooperates to ensure the stability and reliability of the chip power supply, meeting the low-power supply requirements of temperature sensing, signal processing, and other modules.

[0065] Continuing to refer to Figure 3 In the preferred embodiment of the present disclosure, the passive radio frequency tag chip described above further includes a voltage reference module, a first oscillator, a power-on reset module, and a digital baseband signal processing module.

[0066] The voltage reference module is connected with the voltage stabilizer and is used to provide a stable reference voltage based on the supply voltage (VDD); The first oscillator is connected with the voltage reference module and is used to generate a clock signal based on the reference voltage; The power-on reset module is connected with the voltage stabilizer and the digital baseband signal processing module respectively, and is used for monitoring the change of the power supply voltage (VDD), outputting a reset signal to the digital baseband signal processing module when the power supply voltage (VDD) rises and reaches a preset working threshold, so as to reset the digital baseband signal processing module and start working; The temperature sensing circuit is connected between the voltage reference module and the digital baseband signal processing module, and performs temperature sensing based on the reference voltage provided by the voltage reference module, and sends the temperature sensing data to the digital baseband signal processing module; The digital baseband signal processing module encodes the temperature sensing data, and transmits the encoded temperature sensing data to the modulation circuit.

[0067] The voltage reference module of the embodiment provides accurate reference voltage, guarantees the working accuracy of each circuit; the first oscillator generates a synchronous clock signal, realizes the cooperative work of the modules; the power-on reset module ensures the stable start of the chip; the digital baseband signal processing module completes the encoding of the temperature data, and each module forms a closed loop cooperation, which improves the accuracy and stability of the chip signal processing.

[0068] Reference Figure 3 For the temperature sensing circuit described above, the temperature sensing circuit is preferably a digital temperature sensor (i.e. Figure 3 The on-chip digital temperature sensor shown in the foregoing embodiment).

[0069] Figure 4 FIG. 1 is a structural schematic diagram of a rectifier according to an embodiment of the present disclosure.

[0070] Reference Figure 4 In some embodiments of the present disclosure, the rectifier comprises a single-stage alternating current rectification circuit. The single-stage alternating current rectification circuit comprises a first NMOS transistor, a second NMOS transistor, a first PMOS transistor, a second PMOS transistor, a first capacitor, and a second capacitor. The drains of the two NMOS transistors are connected to each other as a common drain end of the NMOS transistors; the drains of the two PMOS transistors are connected to each other as a common drain end of the PMOS transistors. The source of the first NMOS transistor is connected with the source of the first PMOS transistor as a first common source end. The source of the second NMOS transistor is connected with the source of the second PMOS transistor as a second common source end. The gate of the first NMOS transistor is connected with the gate of the first PMOS transistor as a first common gate end, and the first common gate end is connected with the second common source end. The gate of the second NMOS tube is connected with the gate of the second PMOS tube as a second common-gate end, and the second common-gate end is connected with the first common-source end; The first capacitor is connected between the first common-source end and an RFN end, and the second capacitor is connected between the second common-source end and an RFP end; The RFP end is a radio frequency positive input end, used for being connected with the first output end of the first antenna to receive a radio frequency electromagnetic wave positive phase signal transmitted by the first antenna; The RFN end is a radio frequency negative input end, used for being connected with the second output end of the first antenna to receive a radio frequency electromagnetic wave negative phase signal transmitted by the first antenna; The first capacitor is used for coupling the negative phase signal received by the RFN end to the first common-source end, and the second capacitor is used for coupling the positive phase signal received by the RFP end to the second common-source end, so that a differential radio frequency signal enters the single-stage alternating current rectifier circuit and is converted into a direct current voltage signal through rectification.

[0071] With reference to Figure 4 Preferably, the rectifier comprises at least one single-stage alternating current rectifier circuit; When the rectifier comprises one single-stage alternating current rectifier circuit, the common-drain end of the NMOS tube is grounded, and the common-drain end of the PMOS tube is used as a direct current output end (Vout) of the rectifier; When the rectifier comprises a plurality of single-stage alternating current rectifier circuits, the plurality of single-stage alternating current rectifier circuits are connected in cascade in sequence; The connection mode of the cascade connection is as follows: For two adjacent single-stage alternating current rectifier circuits, the common-drain end of the PMOS tube of the former single-stage alternating current rectifier circuit is connected with the common-drain end of the NMOS tube of the latter single-stage alternating current rectifier circuit; The common-drain end of the NMOS tube of the first single-stage alternating current rectifier circuit in the rectifier is grounded, and the common-drain end of the PMOS tube of the last single-stage alternating current rectifier circuit is used as a direct current output end (Vout) of the rectifier; The direct current output end is connected with the limiter.

[0072] The single-stage rectifier circuit of the present disclosure adopts a cross-coupled MOS tube structure to improve the conversion efficiency of radio frequency signals to direct current voltage; supports multi-stage cascade to realize output voltage superposition, can flexibly adapt to power supply requirements according to radio frequency field intensity, and ensures that the chip can obtain sufficient power under different wireless transmission distances.

[0073] Figure 5 is a structural schematic diagram of a temperature sensing circuit of an embodiment of the present disclosure.

[0074] With reference to Figure 5For the passive radio frequency tag chip of each of the above embodiments, preferably, the temperature sensing circuit comprises a temperature sensing diode, a current source, a voltage follower, a ring oscillator and a counter; The current source is connected to the temperature sensing diode for providing a bias current to the temperature sensing diode; The temperature sensing diode is used for sensing the surface temperature of the detection object and converting the temperature change into a voltage change; The voltage follower is connected to the temperature sensing diode for tracking the voltage change on the temperature sensing diode and outputting a follow-up voltage to drive the ring oscillator; The ring oscillator is connected to the voltage follower for converting the change of the follow-up voltage into the change of the frequency of a high-frequency oscillation clock signal and outputting the high-frequency oscillation clock signal; The clock signal input end of the counter is connected to the high-frequency oscillation clock signal, and the enable end of the counter is connected to the low-frequency clock signal generated by the first oscillator, so that the counter is enabled to count the high-frequency oscillation clock signal in the time period (T) when the low-frequency clock signal is high, and a count output value is obtained, which is used as the temperature sensing data.

[0075] In the embodiment, the temperature-voltage conversion is realized by the temperature sensing diode, the voltage follower guarantees the stability of signal transmission, the ring oscillator completes the voltage-frequency conversion, and the counter realizes the frequency quantization. The whole analog-digital conversion link does not need complex calibration, and the temperature sensing accuracy and low power consumption are considered, which is suitable for the working characteristics of the passive tag.

[0076] In some embodiments of the present disclosure, the temperature sensing circuit is connected to the voltage reference module, and the voltage reference module provides a reference voltage for the temperature sensing circuit to support the biasing of the temperature sensing diode and the tracking operation of the voltage follower; The output end of the counter is connected to the digital baseband signal processing module for sending the count output value as temperature sensing data to the digital baseband signal processing module for encoding processing.

[0077] The voltage reference module of the embodiment provides accurate biasing for the temperature sensing circuit, improves the linearity and stability of temperature-voltage conversion, and directly transmits the count output value to the digital baseband module, which simplifies the signal transmission path, reduces power consumption and interference, and guarantees the accuracy of temperature data.

[0078] Continuing to refer to Figure 8 In the preferred embodiment of the present disclosure, the ring oscillator of the present disclosure comprises a plurality of inverters arranged in an odd number of series; The inverter comprises an input end, an output end, a ground end and a power supply end; The power supply end of each inverter is connected with the output end of the voltage follower to receive the follow-up voltage; The ground end of each inverter is grounded; The output end of the former inverter in the adjacent two inverters is connected with the input end of the latter inverter; the input end of the first inverter is connected with the output end of the last inverter to form a closed-loop oscillation structure; The output end of the last inverter outputs the high-frequency oscillation clock signal and inputs into the clock signal input end of the counter; the ring oscillator adjusts the frequency of the high-frequency oscillation clock signal through the change of the follow-up voltage.

[0079] The odd-numbered inverters form a closed-loop oscillation structure, which is simple in structure and low in power consumption; the oscillation frequency is dynamically adjusted according to the follow-up voltage, so that the precise mapping of temperature change is realized, a stable frequency signal is provided for the quantization of the counter, and the temperature measurement accuracy is ensured.

[0080] Figure 6 and Figure 7 The label chip used for the battery core without the lug and the label chip used for the battery core with the lug are respectively shown.

[0081] Referring to Figure 7 For the passive radio frequency label chip of each embodiment described above, the detection object is a battery core or a single battery, the battery core or the single battery has a battery lug; the passive radio frequency label chip is attached close to the position of the battery lug of the battery core or the single battery; the first antenna is a coupling coil structure and is attached to the surface of the battery core or the single battery.

[0082] Referring to Figure 6 For the passive radio frequency label chip of each embodiment described above, the detection object is a battery core or a single battery, the battery core or the single battery does not have a battery lug; the passive radio frequency label chip is arranged in the middle region of the first antenna and is arranged integrally with the first antenna; the first antenna is a coupling coil structure, and the first antenna is attached to the surface of the battery core or the single battery.

[0083] The present disclosure is directed to a battery core with a lug, the chip is attached close to the lug, and the temperature measurement accuracy is improved by using the characteristic that the temperature of the lug area is representative; for a battery core without a lug, the chip and the antenna are arranged integrally, and the installation process is simplified; the coupling coil antenna is adapted to near-field wireless transmission, and the energy collection efficiency can be optimized by adjusting the number of turns or the area, and the layout requirements of battery cores of different shapes are adapted.

[0084] The present disclosure also provides a radio frequency read-write chip.

[0085] Figure 8is a structural schematic block diagram of a radio frequency read-write chip of one embodiment of the present disclosure.

[0086] Reference Figure 8 In some embodiments of the present disclosure, the radio frequency read-write chip of the present disclosure comprises: a transceiving unit for transmitting radio frequency electromagnetic waves carrying instructions and receiving a return signal containing temperature sensing data returned by a passive radio frequency tag chip; a carrier generating unit for generating a radio frequency carrier; a quadrature mixing receiving unit connected between the transceiving unit and the carrier generating unit, for quadrature mixing processing the return signal with the radio frequency carrier to obtain an intermediate frequency signal; a double path demodulation unit connected to the quadrature mixing receiving unit, for double path demodulation processing the intermediate frequency signal to obtain a digital signal corresponding to the temperature sensing data; a digital processing unit connected to the double path demodulation unit, for decoding processing the digital signal to obtain temperature sensing data corresponding to the digital signal; The passive radio frequency tag chip is any one of the passive radio frequency tag chips described above in the embodiments of the present disclosure.

[0087] Among them, the radio frequency read-write chip can serve as a concentrator of the BMS wireless temperature measurement system, integrating signal transceiving, carrier generation, mixing demodulation and data processing functions, improving the resolution accuracy of the return signal through quadrature mixing and double path demodulation, realizing accurate acquisition of passive tag temperature data, and at the same time, providing power for the tag through the radio frequency carrier, without the need for an additional power supply module.

[0088] In some other embodiments of the present disclosure, the above-mentioned transceiving unit can not be part of the radio frequency read-write chip but a separate device.

[0089] Figure 9 is a structural schematic block diagram of a radio frequency read-write chip of another embodiment of the present disclosure.

[0090] Reference Figure 9 In the preferred embodiments of the present disclosure, the digital processing unit of the present disclosure is also used to generate control instructions for controlling the passive radio frequency tag chip; Among them, the radio frequency read-write chip further comprises: a modulated transmitting unit connected between the digital processing unit and the carrier generating unit, for modulating the control instructions onto the radio frequency carrier and transmitting them through the transceiving unit after power amplification.

[0091] The modulation transmitting unit of the present disclosure loads control instructions to the radio frequency carrier, ensures signal transmission distance and penetration ability after power amplification, realizes remote control and energy supply of multiple passive tags, and completes the closed-loop interaction of "instruction issuing-data receiving" with the digital processing unit.

[0092] Figure 10 is a structure diagram of the radio frequency read-write chip of one preferred embodiment of the present disclosure.

[0093] It should be noted that, Figure 10 The circuit structure shown in the figure should not be understood as a limitation of the technical solutions of the present disclosure.

[0094] Reference Figure 10 In some embodiments of the present disclosure, the transceiving unit of the radio frequency read-write chip of the present disclosure includes a second antenna and a transceiving switch; The transceiving switch is used to switch the working mode of the second antenna: In the transmitting mode, the modulation transmitting unit is connected with the second antenna, and in the receiving mode, the second antenna is connected with the quadrature frequency mixing receiving unit.

[0095] The transceiving switch of the present disclosure realizes the quick switching of the transceiving mode of the second antenna, avoids the mutual interference of the transmitting signal and the receiving signal, improves the stability and reliability of the signal transmission, simplifies the antenna layout, and reduces the hardware complexity of the chip.

[0096] Reference Figure 10 In some embodiments of the present disclosure, the carrier generating unit of the present disclosure is a radio frequency carrier generator, which is used to generate I and Q quadrature radio frequency carriers.

[0097] Reference Figure 10 In some embodiments of the present disclosure, the quadrature frequency mixing receiving unit of the radio frequency read-write chip of the present disclosure includes a first mixer and a second mixer; The first mixer is connected with the I output end of the transceiving unit and the carrier generating unit, and is used to mix the return signal and the I quadrature radio frequency carrier to obtain the I intermediate frequency signal; The second mixer is connected with the Q output end of the transceiving unit and the carrier generating unit, and is used to mix the return signal and the Q quadrature radio frequency carrier to obtain the Q intermediate frequency signal.

[0098] The present disclosure decomposes the return signal into in-phase and quadrature components by I / Q quadrature radio frequency carrier and double mixers, completely retains the amplitude and phase information of the signal, avoids signal distortion, improves the analysis ability of weak signals, and adapts to the low amplitude characteristics of the passive tag return signal.

[0099] Reference Figure 10In the preferred embodiment of the present disclosure, the dual-channel demodulation unit of the radio frequency read-write chip of the present disclosure comprises a first demodulation path corresponding to the I-channel intermediate frequency signal and a second demodulation path corresponding to the Q-channel intermediate frequency signal. The two-channel demodulation paths work in parallel to process the in-phase component and the quadrature component of the intermediate frequency signal respectively.

[0100] The present disclosure processes the I / Q intermediate frequency signal in parallel through the dual-channel demodulation paths, realizes complete restoration of the signal, significantly improves the demodulation accuracy and anti-interference ability compared with single-channel demodulation, and guarantees accurate analysis of the temperature data in a complex battery pack environment.

[0101] With reference to the above Figure 10 Preferably, each of the demodulation paths of the radio frequency read-write chip of the present disclosure comprises a filtering module, an amplification module, a gain adjustment module, and an analog-to-digital conversion module. The filtering module is used to filter signal clutter and high-frequency noise. The amplification module is used to improve the signal strength. The gain adjustment module is used to dynamically adjust the signal gain. The analog-to-digital conversion module is used to convert the analog signal to a digital signal.

[0102] The present disclosure suppresses environmental noise through the filtering module, improves the strength of weak signals through the amplification module, adapts to the change of signal amplitude at different distances through the gain adjustment module, and completes analog-digital conversion through the analog-to-digital conversion module. The four-level processing link ensures the purity and analyzability of the intermediate frequency signal, and guarantees the accurate extraction of the temperature data.

[0103] Preferably, the filtering module comprises a band-pass filter and a low-pass filter. The band-pass filter is used to filter the clutter of the intermediate frequency signal, and the low-pass filter is used to filter the high-frequency noise of the intermediate frequency signal.

[0104] Preferably, the amplification module is an amplifier, the gain adjustment module is a variable gain amplifier (VGA), and the analog-to-digital conversion module is an analog-to-digital converter (ADC).

[0105] For the radio frequency read-write chip of each of the above embodiments, the digital processing unit comprises a decoding circuit for decoding the digital signal to analyze the temperature sensing data in the return signal.

[0106] The decoding circuit of the present disclosure adapts to the encoding format of the passive tag, quickly analyzes the temperature sensing data in the digital signal, and cooperates with the protocol processing function of the digital processing unit to realize efficient extraction of the temperature data and subsequent instruction generation.

[0107] With reference to the above Figure 10In some embodiments of the present disclosure, the modulation transmitting unit comprises a filtering unit, a mixing unit and a power amplification unit. The filtering unit is configured to filter the noise of the control instruction. The mixing unit is configured to mix the control instruction with the radio frequency carrier to generate a radio frequency signal carrying the control instruction. The power amplification unit is configured to amplify the power of the radio frequency signal.

[0108] Preferably, the filtering unit is a low-pass filter, the mixing unit is a mixer, and the power amplification unit is a power amplifier.

[0109] In some embodiments of the present disclosure, the digital processing unit is configured to perform the following operations: Figure 10 The digital processing unit of the present disclosure is further configured to perform round-robin read-write control on a plurality of passive radio frequency tag chips based on an anti-collision protocol, and generate a control instruction for controlling the passive radio frequency tag chips.

[0110] The anti-collision protocol of the present disclosure supports the differentiation and round-robin access of read-write chips to multiple tags. The target tag is selected by identifying the difference in the return characteristics (such as the return start time) of the tags. After data interaction, the tag enters a silent state to avoid signal collision caused by multiple tags responding at the same time, and to realize, for example, temperature data collection of, for example, 16 or more tags within 1s, thereby improving the detection efficiency of the system. At the same time, the anti-collision protocol supports high-temperature interruption alarm function. When the tag detects temperature anomaly, it can actively report, thereby ensuring the real-time performance of battery cell safety monitoring.

[0111] Figure 11 FIG. 1 is a schematic block diagram of a wireless temperature measurement system according to an embodiment of the present disclosure.

[0112] In some embodiments of the present disclosure, the wireless temperature measurement system of the present disclosure comprises: Figure 11 In some embodiments of the present disclosure, the wireless temperature measurement system of the present disclosure comprises: A plurality of passive radio frequency tag chips (three are exemplarily shown), each of which is attached to the surface of a battery cell or a battery monomer; A radio frequency read-write chip, which transmits radio frequency electromagnetic waves with the passive radio frequency tag chips in a wireless manner; The radio frequency electromagnetic waves emitted by the radio frequency read-write chip serve as the energy source of the passive radio frequency tag chips.

[0113] The wireless temperature measurement system of the present disclosure adopts the architecture of “multiple tags + read-write chip”. The tags are attached to the surface of each battery cell to realize cell-level temperature measurement. The read-write chip simultaneously completes the energy supply and data transmission of the tags through radio frequency electromagnetic waves, without the need for wired power supply and communication link, thereby completely solving the problems of weight, cost, space and reliability of the traditional wired solution.

[0114] In some embodiments of the present disclosure, the radio frequency read-write chip of the wireless temperature measurement system of the present disclosure is arranged on a battery module, and the radio frequency read-write chip on the battery module is used to transmit radio frequency electromagnetic waves between the passive radio frequency tag chip on each battery cell or battery monomer in the battery module through a wireless manner.

[0115] In the present embodiment, the read-write chip is arranged on the battery module, which shortens the transmission distance with the tag in the module, improves the energy transmission efficiency and data communication stability, realizes the localized collection and preliminary processing of the battery cell temperature data in the module, and reduces the system-level data transmission pressure.

[0116] In some other embodiments of the present disclosure, the number of radio frequency read-write chips of the wireless temperature measurement system is multiple; One radio frequency read-write chip is arranged on a battery pack, and the battery pack includes multiple battery modules; Each battery module is arranged with one radio frequency read-write chip; The passive radio frequency tag chip and the radio frequency read-write chip on the corresponding battery module transmit radio frequency electromagnetic waves through a wireless manner, and / or the passive radio frequency tag chip and the radio frequency read-write chip on the battery pack transmit radio frequency electromagnetic waves through a wireless manner.

[0117] The wireless temperature measurement system of the present disclosure supports multi-level read-write chip layout, the module-level read-write chip is responsible for local tag data collection, the battery pack-level read-write chip is responsible for global data aggregation and uploading, and the tag can flexibly select the communication object to adapt to the layout requirements of battery packs of different scales; The system can use low-frequency carriers such as 125KHz, 13.56MHz or 433MHz, the signal penetration ability is strong, and there is no need for bus antenna assistance, which realizes true wireless communication and reduces the risk of communication failure caused by damaged antenna.

[0118] For the wireless temperature measurement system of each of the above embodiments, further comprising: An analog front-end chip (AFE chip) is used to detect the voltage and / or current of multiple series-connected battery cells in the battery module, and transmit the detection results to the radio frequency read-write chip of the battery module.

[0119] The analog front-end chip is responsible for detecting the voltage, current and other electrical parameters of the battery cell, and the radio frequency read-write chip is responsible for collecting and wirelessly transmitting temperature data, and the two work together to realize the full-parameter monitoring of the battery cell; The detection results are uploaded through a wireless manner, only the local wired connection between the battery cell and the analog front-end chip is retained, the long-distance communication cable is saved, and the battery pack wiring is simplified.

[0120] For the wireless temperature measurement system of each of the above embodiments, the passive radio frequency tag chip is the passive radio frequency tag chip of any one of the above embodiments of the present disclosure.

[0121] For the wireless temperature measurement system of each of the above embodiments, the radio frequency read-write chip is the radio frequency read-write chip of any one of the above embodiments of the present disclosure.

[0122] The present disclosure also provides a battery system.

[0123] Figure 12 FIG. 1 is a schematic diagram of a battery system according to an embodiment of the present disclosure.

[0124] Reference Figure 12 In some embodiments of the present disclosure, the battery system of the present disclosure comprises: a battery device, which is a battery module or a battery pack comprising a plurality of battery modules; and a wireless temperature measurement system of any one of the embodiments of the present disclosure, which is used for wireless temperature measurement of a battery cell or a battery monomer in the battery device.

[0125] The battery system of the present disclosure integrates a wireless temperature measurement system, realizes accurate temperature monitoring at the battery cell level and wireless transmission of voltage and current parameters, greatly reduces wired connections, reduces the weight and cost of the battery pack, saves internal space, improves assembly and maintenance efficiency, reduces the risk of joint failure, and ensures the safety and reliability of the battery system operation.

[0126] In the description of the present disclosure, the description of the terms "one embodiment / way", "some embodiments / ways", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment / way or example are included in at least one embodiment / way or example of the present disclosure. In the present disclosure, the illustrative description of the above terms does not necessarily refer to the same embodiment / way or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments / ways or examples. In addition, the skilled in the art can combine and combine the features of different embodiments / ways or examples described in the present disclosure without contradiction.

[0127] 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 indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present disclosure, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0128] Those skilled in the art should understand that the above embodiments are only for clearly illustrating the present disclosure, and are not intended to limit the scope of the present disclosure. Based on the above disclosure, other changes or modifications can also be made by those skilled in the art, and these changes or modifications are still within the scope of the present disclosure.

Claims

1. A passive radio frequency tag chip capable of being attached to the surface of a detection object, characterized by, The temperature sensing circuit is configured to sense a surface temperature of the detection object and obtain temperature sensing data. The energy acquisition circuit is configured to acquire energy from the radio frequency electromagnetic wave to at least power the temperature sensing circuit. The passive radio frequency tag chip further comprises: a first antenna configured to receive the radio frequency electromagnetic wave; 2. The passive radio frequency tag chip of claim 1, wherein, a demodulation circuit connected to the first antenna and configured to demodulate the radio frequency electromagnetic wave received by the first antenna to demodulate a control instruction carried in the radio frequency electromagnetic wave; a modulation circuit connected to the first antenna and configured to send a modulated signal containing the temperature sensing data via the first antenna. The energy acquisition circuit comprises a rectifier, a limiter, and a voltage stabilizer connected in sequence. The rectifier is connected to the first antenna and configured to convert the radio frequency electromagnetic wave received by the first antenna into direct current energy.

3. The passive radio frequency tag chip according to claim 1 or 2, characterized in that, The limiter is configured to clamp and limit a voltage of the direct current energy to obtain a voltage signal after voltage limiting. The voltage stabilizer is configured to convert the voltage signal after voltage limiting into a supply voltage. The passive radio frequency tag chip further comprises a voltage reference module, a first oscillator, a power-on reset module, and a digital baseband signal processing module. The voltage reference module is connected to the voltage stabilizer and configured to provide a stable reference voltage based on the supply voltage.

4. The passive radio frequency tag chip of claim 3, wherein, The first oscillator is connected to the voltage reference module and configured to generate a clock signal based on the reference voltage. The power-on reset module is connected to the voltage stabilizer and the digital baseband signal processing module and configured to monitor a change in the supply voltage, output a reset signal to the digital baseband signal processing module when the supply voltage rises to a preset working threshold, reset the digital baseband signal processing module, and start working. The temperature sensing circuit is connected between the voltage reference module and the digital baseband signal processing module, performs temperature sensing based on the reference voltage provided by the voltage reference module, and sends the temperature sensing data to the digital baseband signal processing module. The digital baseband signal processing module encodes the temperature sensing data and transmits the encoded temperature sensing data to the modulation circuit. The temperature sensing circuit is a digital temperature sensor. The rectifier comprises a single-stage alternating current rectification circuit.

5. The passive radio frequency tag chip of claim 1, wherein, The single-stage alternating current rectification circuit comprises a first NMOS transistor, a second NMOS transistor, a first PMOS transistor, a second PMOS transistor, a first capacitor, and a second capacitor.

6. The passive radio frequency tag chip of claim 3, wherein, The drains of the two NMOS transistors are connected to each other as a common drain of the NMOS transistors. The source of the first NMOS transistor is connected to the source of the first PMOS transistor as a first common source. The source of the second NMOS transistor is connected to the source of the second PMOS transistor as a second common source. ​ ​ The gate of the first NMOS transistor is connected with the gate of the first PMOS transistor as a first common gate end, and the first common gate end is connected with the second common source end; The gate of the second NMOS transistor is connected with the gate of the second PMOS transistor as a second common gate end, and the second common gate end is connected with the first common source end; The first capacitor is connected between the first common source end and an RFN end, and the second capacitor is connected between the second common source end and an RFP end; The RFP end is a radio frequency positive input end, which is used for being connected with the first output end of the first antenna to receive a radio frequency electromagnetic wave positive phase signal transmitted by the first antenna; The RFN end is a radio frequency negative input end, which is used for being connected with the second output end of the first antenna to receive a radio frequency electromagnetic wave negative phase signal transmitted by the first antenna; The first capacitor is used for coupling the negative phase signal received by the RFN end to the first common source end, and the second capacitor is used for coupling the positive phase signal received by the RFP end to the second common source end, so that a differential radio frequency signal enters the single-stage alternating current rectifier circuit and is converted into a direct current voltage signal through rectification.

7. The passive radio frequency tag chip according to any one of claims 1 to 6, wherein, The rectifier comprises at least one single-stage alternating current rectifier circuit; When the rectifier comprises one single-stage alternating current rectifier circuit, the common drain end of the NMOS transistor is grounded, and the common drain end of the PMOS transistor is used as a direct current output end of the rectifier; When the rectifier comprises a plurality of single-stage alternating current rectifier circuits, the plurality of single-stage alternating current rectifier circuits are connected in cascade; The connection mode of the cascade connection is as follows: For two adjacent single-stage alternating current rectifier circuits, the common drain end of the PMOS transistor of a previous single-stage alternating current rectifier circuit is connected with the common drain end of the NMOS transistor of a subsequent single-stage alternating current rectifier circuit; The common drain end of the NMOS transistor of a first single-stage alternating current rectifier circuit in the rectifier is grounded, and the common drain end of the PMOS transistor of a last single-stage alternating current rectifier circuit is used as a direct current output end of the rectifier; The direct current output end is connected with the amplitude limiter; Optionally, the temperature sensing circuit comprises a temperature sensing diode, a current source, a voltage follower, a ring oscillator and a counter. The current source is connected with the temperature sensing diode and is used for providing a bias current for the temperature sensing diode; The temperature sensing diode is used for sensing the surface temperature of the detection object and converting the temperature change into a voltage change; The voltage follower is connected with the temperature sensing diode and is used for tracking the voltage change on the temperature sensing diode and outputting a follow-up voltage to drive the ring oscillator; The ring oscillator is connected with the voltage follower and is used for converting the change of the follow-up voltage into the frequency change of a high-frequency oscillation clock signal and outputting the high-frequency oscillation clock signal; The clock signal input end of the counter is connected with the high-frequency oscillation clock signal, and the enable end of the counter is connected with the low-frequency clock signal generated by the first oscillator, so that the counter is enabled to count the high-frequency oscillation clock signal in the time period in which the low-frequency clock signal is high, and a count output value is obtained, which is used as the temperature sensing data. Optionally, the temperature sensing circuit is connected with the voltage reference module, and the voltage reference module provides a reference voltage for the temperature sensing circuit to support biasing of the temperature sensing diode and tracking operation of the voltage follower; An output end of the counter is connected with the digital baseband signal processing module, and the counter output value is sent to the digital baseband signal processing module as temperature sensing data for encoding processing; Optionally, the ring oscillator comprises a plurality of inverters, and the plurality of inverters are arranged in an odd number of series connection; The inverter comprises an input end, an output end, a ground end and a power supply end; The power supply end of each inverter is connected with the output end of the voltage follower to receive the follow-up voltage; The ground end of each inverter is grounded. In adjacent two inverters, the output end of the former inverter is connected with the input end of the latter inverter; the input end of the first inverter is connected with the output end of the last inverter to form a closed loop oscillation structure. The output end of the last inverter outputs the high-frequency oscillation clock signal and inputs the clock signal input end of the counter; the ring oscillator adjusts the frequency of the high-frequency oscillation clock signal through the change of the follow-up voltage; Optionally, the detection object is a battery core or a single battery, and the battery core or the single battery has a battery tab; The passive radio frequency tag chip is attached close to the position of the battery tab of the battery core or the single battery; The first antenna is a coupling coil structure and is attached to the surface of the battery core or the single battery; Optionally, the detection object is a battery core or a single battery, and the battery core or the single battery does not have a battery tab; The passive radio frequency tag chip is arranged in the middle area of the first antenna and is arranged integrally with the first antenna; The first antenna is a coupling coil structure, and the first antenna is attached to the surface of the battery core or the single battery.

8. A radio frequency read / write chip, characterized by Comprise: A transceiving unit for transmitting radio frequency electromagnetic waves carrying instructions and receiving return signals containing temperature sensing data returned by the passive radio frequency tag chip; A carrier generating unit for generating a radio frequency carrier; A quadrature mixing receiving unit connected between the transceiving unit and the carrier generating unit for performing quadrature mixing processing on the return signal and the radio frequency carrier to obtain an intermediate frequency signal; A double-path demodulation unit connected with the quadrature mixing receiving unit for performing double-path demodulation processing on the intermediate frequency signal to obtain a digital signal corresponding to the temperature sensing data; A digital processing unit connected with the double-path demodulation unit for decoding the digital signal to obtain temperature sensing data corresponding to the digital signal; The passive radio frequency tag chip is any one of the passive radio frequency tag chips in claims 1 to 12; Optionally, the digital processing unit is further configured to generate a control instruction for controlling the passive radio frequency tag chip; The radio frequency read-write chip further comprises: A modulation transmitting unit connected between the digital processing unit and the carrier generating unit for modulating the control instruction onto the radio frequency carrier and transmitting the radio frequency carrier after power amplification through the transceiving unit. Optionally, the transceiving unit comprises a second antenna and a transceiving switch; the transceiving switch is configured to switch the operation mode of the second antenna: in the transmitting mode, the modulated transmitting unit is connected with the second antenna, and in the receiving mode, the second antenna is connected with the quadrature mixing receiving unit; Optionally, the carrier generating unit is a radio frequency carrier generator configured to generate I and Q quadrature radio frequency carriers; Optionally, the quadrature mixing receiving unit comprises a first mixer and a second mixer; the first mixer is connected with the I output end of the transceiving unit and the carrier generating unit, and is configured to mix the return signal with the I quadrature radio frequency carrier to obtain an I intermediate frequency signal; the second mixer is connected with the Q output end of the transceiving unit and the carrier generating unit, and is configured to mix the return signal with the Q quadrature radio frequency carrier to obtain a Q intermediate frequency signal; Optionally, the dual-channel demodulation unit comprises a first demodulation path corresponding to the I intermediate frequency signal, and a second demodulation path corresponding to the Q intermediate frequency signal; the two demodulation paths work in parallel and are configured to process the in-phase component and the quadrature component of the intermediate frequency signal respectively; Optionally, each demodulation path comprises a filtering module, an amplifying module, a gain adjusting module and an analog-to-digital conversion module; the filtering module is configured to filter signal noise and high frequency noise; the amplifying module is configured to enhance the signal strength; the gain adjusting module is configured to dynamically adjust the signal gain; the analog-to-digital conversion module is configured to convert the analog signal into a digital signal; Optionally, the filtering module comprises a band-pass filter and a low-pass filter; the band-pass filter is configured to filter the noise of the intermediate frequency signal, and the low-pass filter is configured to filter the high frequency noise of the intermediate frequency signal; Optionally, the amplifying module is an amplifier, the gain adjusting module is a variable gain amplifier, and the analog-to-digital conversion module is an analog-to-digital converter; Optionally, the digital processing unit comprises a decoding circuit configured to decode the digital signal to parse the temperature sensing data in the return signal; Optionally, the modulated transmitting unit comprises a filtering unit, a mixing unit and a power amplifying unit; the filtering unit is configured to filter the noise of the control instruction; the mixing unit is configured to mix the control instruction with the radio frequency carrier to generate a radio frequency signal carrying the control instruction; the power amplifying unit is configured to amplify the power of the radio frequency signal; Optionally, the filtering unit is a low-pass filter, the mixing unit is a mixer, and the power amplifying unit is a power amplifier; Optionally, the digital processing unit is further configured to perform round-robin read-write control on multiple passive radio frequency tag chips based on an anti-collision protocol, and generate control instructions for controlling the passive radio frequency tag chips.

9. A wireless temperature measurement system, characterized by It comprises: a plurality of passive radio frequency tag chips, each of which is attached to the surface of a battery core or a battery cell; and a radio frequency read-write chip, which transmits radio frequency electromagnetic waves with the passive radio frequency tag chip through wireless means; the radio frequency electromagnetic waves emitted by the radio frequency read-write chip serve as the energy source for the passive radio frequency tag chip; Optionally, the radio frequency read-write chip is arranged on the battery module, and the radio frequency read-write chip on the battery module is configured to perform radio frequency electromagnetic wave transmission between the passive radio frequency tag chip on each battery cell or battery monomer in the battery module through a wireless manner. Optionally, the number of the radio frequency read-write chips is multiple. One radio frequency read-write chip is arranged on the battery pack, and the battery pack includes multiple battery modules. Each battery module is arranged with one radio frequency read-write chip. The passive radio frequency tag chip and the radio frequency read-write chip on the corresponding battery module perform radio frequency electromagnetic wave transmission through a wireless manner, and / or the passive radio frequency tag chip and the radio frequency read-write chip on the battery pack perform radio frequency electromagnetic wave transmission through a wireless manner. Optionally, further comprising: an analog front-end chip configured to detect the voltage and / or current of multiple series-connected battery cells in the battery module and transmit the detection result to the radio frequency read-write chip of the battery module; Optionally, the passive radio frequency tag chip is the passive radio frequency tag chip according to any one of claims 1 to 7. And / or, the radio frequency read-write chip is the radio frequency read-write chip according to claim 8.

10. A battery system characterized by, including: a battery device, which is a battery module or a battery pack including multiple battery modules; and the wireless temperature measurement system according to claim 9 is configured to perform wireless temperature measurement on the battery cell or battery monomer in the battery device. ​

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