Flexible UHF RFID tag integrated with battery unit

Abstract

The invention relates to the technical field of radio frequency antennas, and discloses a flexible UHF RFID tag integrated with a battery unit. The flexible UHF RFID tag integrated with the battery unit is integrally T-shaped, and comprises a metal patch layer which comprises a radiation patch main body, a first slotting structure and a second slotting structure, and the first slotting structure and the second slotting structure are arranged on the radiation patch main body; the first slotted structure is an L-shaped slotted structure, one end of the L-shaped slotted structure is located at the edge of the radiation patch main body, and the other end of the L-shaped slotted structure is located in the radiation patch main body; the second slotting structure is located on the inner side of the L-shaped slotting structure. A grounding layer, wherein the metal patch layer is arranged on the grounding layer; and the dielectric layer comprises a flexible substrate, a metal wire arranged in the flexible substrate and a chip. The label provided by the invention can realize sensing monitoring in an extremely narrow environment with metal on both sides. The vertical part of the chip of the T-shaped label is inserted between the two batteries, and the horizontal part of the T-shaped label is attached to the side walls of the batteries to achieve sensing detection.

Description

Technical Field

[0001] The present invention relates to the technical field of radio frequency antennas, and particularly to a flexible UHF RFID tag integrated with battery units. Background Art

[0002] In order to better manage new energy batteries, it is necessary to sense and monitor new energy batteries during operation. In order to obtain more accurate and immediate information data, it is significantly effective to place the tag chip between two adjacent batteries in the new energy battery pack. New energy batteries are commonly square aluminum shells, and two batteries in the battery pack will be adjacent and close to each other, and the gap distance in the middle is extremely small. Traditional tag antennas generally use hard materials with relatively thick thickness, and in a metal environment, anti-metal tag antennas with antenna structures such as microstrip antennas and PIFA antennas are used. However, most of these anti-metal tag antennas face a metal object on one side. Using a traditional anti-metal tag between adjacent batteries, first of all, the thickness will be a limitation, and since the chip needs to sense and monitor between two adjacent batteries, there are aluminum shell metals on both sides, which will cause the traditional anti-metal tag to be unable to sense and monitor normally. In addition, the existing tag antennas have a narrow working bandwidth and cannot monitor new energy batteries well.

[0003] Therefore, the prior art still needs to be further improved and enhanced. Summary of the Invention

[0004] In view of the above deficiencies of the prior art, the purpose of the present invention is to provide a flexible UHF RFID tag integrated with battery units. The substrate of the flexible UHF RFID tag integrated with battery units is flexible and ultra-thin, has very good bending performance, and can be placed between two adjacent batteries in the new energy battery pack. The aluminum shell of the new energy battery is wrapped with a battery blue film, which avoids direct contact between the tag and the metal aluminum surface. By placing the entire "vertical" part of the "T"-shaped tag where the chip is located between two adjacent batteries and bending at the connection of the "vertical" and "horizontal" parts, the "horizontal" part of the "T"-shaped tag is attached to the side wall of the battery, so as to be able to realize sensing and monitoring in an extremely narrow environment with metals on both sides. At the same time, the impedance matching effect between the tag antenna and the chip is good, and the tag has a relatively wide working bandwidth.

[0005] The above object of the present invention is achieved by the following technical solution: A flexible UHF RFID tag integrated with battery units, wherein the flexible UHF RFID tag integrated with battery units is in an overall "T" shape and includes:

[0006] The metal patch layer includes a radiation patch body, a first slotted structure and a second slotted structure disposed on the radiation patch body; the first slotted structure is an L-shaped slotted structure, one end of the L-shaped slotted structure is located at the edge of the radiation patch body, and the other end is located inside the radiation patch body; the second slotted structure is located inside the L-shaped slotted structure;

[0007] The ground layer, and the metal patch layer is disposed on the ground layer;

[0008] The dielectric layer includes a flexible matrix, a metal wire and a chip disposed in the flexible matrix; the metal wire is composed of a straight metal wire and a bent metal wire connected to the straight metal wire; an installation position for installing the chip is provided at one end of the straight metal wire close to the bent metal wire; one end of the dielectric layer is fixed between the ground layer and the dielectric layer, and one end of the straight metal wire is connected to the metal patch layer; the bent metal wire is away from the ground layer.

[0009] The following are the preferred technical solutions of the present invention, but do not limit the technical solutions provided by the present invention. Through the following preferred technical solutions, the objectives and beneficial effects of the present invention can be better achieved and realized.

[0010] As a preferred technical solution, for the flexible UHF RFID tag integrated with a battery unit, the flexible UHF RFID tag integrated with a battery unit further includes a third slotted structure; the third slotted structure is entirely located inside the radiation patch body and is away from the second slotted structure.

[0011] As a preferred technical solution, for the flexible UHF RFID tag integrated with a battery unit, the flexible UHF RFID tag integrated with a battery unit further includes a fourth slotted structure; the fourth slotted structure is located between the second slotted structure and the third slotted structure, and one end is located at the edge of the radiation patch body.

[0012] As a preferred technical solution, for the flexible UHF RFID tag integrated with a battery unit, the orthographic projections of the second slotted structure and the third slotted structure are rectangles.

[0013] As a preferred technical solution, for the flexible UHF RFID tag integrated with a battery unit, the area of the second slotted structure is larger than the area of the third slotted structure.

[0014] As a preferred technical solution, for the flexible UHF RFID tag integrated with a battery unit, the orthographic projection of the fourth slotted structure is a rectangle, and the area of the fourth slotted structure is smaller than the area of the third slotted structure.

[0015] As a preferred technical solution, for the flexible UHF RFID tag integrated with the battery unit, the material of the flexible substrate is polyimide.

[0016] As a preferred technical solution, for the flexible UHF RFID tag integrated with the battery unit, the bent metal wire has a "Ji" (Chinese character for "several") shaped structure.

[0017] As a preferred technical solution, for the flexible UHF RFID tag integrated with the battery unit, the thickness of the dielectric layer is less than or equal to 0.2 mm.

[0018] As a preferred technical solution, for the flexible UHF RFID tag integrated with the battery unit, the frequency band generated by the flexible UHF RFID tag integrated with the battery unit is 876 - 946 MHz.

[0019] Advantageous effects: Compared with the prior art, the tag provided by the present invention can achieve sensing and monitoring in an extremely narrow environment with metal on both sides. By inserting the "vertical stroke" of the chip in the "T" - shaped tag between two batteries and pasting the "horizontal stroke" of the "T" - shaped tag on the side wall of the battery, sensing detection is achieved. In the ultra - high frequency band, it can generate a relatively wide - bandwidth frequency band, ranging from 876 MHz to 946 MHz, which comprehensively covers the latest UHF RFID frequency band from 920 MHz to 925 MHz and has a certain amount of redundant bandwidth. This ensures the adaptability, stability, and feasibility of energy transmission during actual use. The tag has a reflection coefficient lower than - 10 dB in the frequency band from 876 MHz to 946 MHz, with the lowest reflection coefficient of - 43 dB in this frequency band and a center frequency of 920 MHz. This ensures that most of the energy and signal power of the antenna are transmitted well, and at the same time, it shows that the antenna impedance matching is good, ensuring stability during actual use. Among them, the polyimide substrate is an FPC flexible board, which has very good bending performance. At the same time, the antenna structure is a completely planar structure, which is easy to process and realize. By adjusting the size and relative position of the slotted structure, it is easy to adjust the impedance of the tag antenna and achieve good impedance matching. Description of the Drawings

[0020] Figure 1 It is a three - dimensional structure schematic diagram of a flexible UHF RFID tag integrated with a battery unit for a new - energy battery sensing system according to the present invention.

[0021] Figure 2 It is a schematic diagram of the actual application of a flexible UHF RFID tag integrated with a battery unit for a new - energy battery sensing system in a new - energy battery pack according to the present invention.

[0022] Figure 3Top - layer planar schematic diagram of a flexible UHF RFID tag integrated with battery cells for a new - energy battery sensing system according to the present invention.

[0023] Figure 4 Bottom - layer planar schematic diagram of a flexible UHF RFID tag integrated with battery cells for a new - energy battery sensing system according to the present invention.

[0024] Figure 5 Specific structural diagram of the top - layer slotted patch of a flexible UHF RFID tag integrated with battery cells for a new - energy battery sensing system according to the present invention.

[0025] Figure 6 Specific structural diagram of the top - layer feeding point of a flexible UHF RFID tag integrated with battery cells for a new - energy battery sensing system according to the present invention.

[0026] Figure 7 Simulated reflection coefficient diagram of a flexible UHF RFID tag integrated with battery cells for a new - energy battery sensing system according to the present invention from 860 MHz to 960 MHz.

[0027] Figure 8 Simulated impedance - matching diagram of a flexible UHF RFID tag integrated with battery cells for a new - energy battery sensing system according to the present invention from 860 MHz to 960 MHz. Detailed implementation manners

[0028] It should be noted that, without conflict, the embodiments and features in the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the drawings and in combination with the embodiments.

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and in no way restricts the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0030] Note that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments of the present invention. As used herein, unless the context clearly dictates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprises" and / or "comprising" are used in this specification, they specify the presence of the stated features, steps, operations, devices, components, and / or combinations thereof.

[0031] Unless otherwise specifically stated, the relative arrangements of the components and steps, numerical expressions, and values set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be clear that, for the sake of description, the dimensions of the various parts shown in the drawings are not drawn in actual proportional relationships. For technologies, methods, and devices known to those of ordinary skill in the relevant art, they may not be discussed in detail, but where appropriate, the said technologies, methods, and devices should be regarded as part of the authorized specification. In all the examples shown and discussed herein, any specific values should be construed as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that like reference numerals and letters denote like items in the following figures, and thus, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0032] For the sake of description, spatial relative terms such as "above", "over", "on the upper surface", "upper" etc. may be used herein to describe the spatial positional relationship of one device or feature to other devices or features as shown in the figures. It should be understood that the spatial relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is inverted, the device described as "above" or "over" other devices or structures will then be positioned "below" or "beneath" the other devices or structures. Thus, the exemplary term "above" can include both the orientations of "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and corresponding interpretations of the spatial relative descriptions used herein will be made.

[0033] As

[0034] As Figure 1As shown in the figure, a flexible UHF RFID tag 10 integrated with a battery unit provided by the present invention includes, from top to bottom, a top metal patch layer 100, a dielectric layer 200, and a bottom ground layer 300; the top metal patch layer 100 is based on a rectangular patch and includes a radiation patch body 101, a first "L"-shaped slot structure 103, a second rectangular slot structure 102, a third rectangular slot structure 104, a fourth rectangular slot structure 105, a straight metal wire 106, and a bent metal wire 107; the intermediate dielectric layer 200 can be a polyimide material with a thickness of 0.2 mm; the bottom metal ground layer is a rectangular patch 301 at the "horizontal bar" of the "T"-shaped tag. Among them, one end of the dielectric layer 200 is fixed between the metal patch layer 100 and the ground layer 300. The width of the L-shaped slot structure (the width of the slot) can be set according to actual needs, with a unified width, or it can be set to different widths, such as the width on one side of the L shape being greater than the width on the other side (as Figure 5 shown).

[0035] As Figure 3 shown, the basis of the metal patch layer is a rectangular patch 101, and slotting operations are performed on it; as Figure 5 shown, the side of the second rectangular slot structure 102 is the first "L"-shaped slot structure 103, which can make the antenna generate a meander structure, generate a large inductance for the antenna, and thus achieve impedance matching of the tag antenna; by adjusting the sizes of the third rectangular slot structure 104 and the fourth rectangular slot structure 105, the antenna impedance can also be adjusted within a small range. Connecting the rectangular patches is a very long straight metal wire 106, and the end is a bent metal wire 107. The bending of the metal wire can increase the antenna bandwidth to a certain extent. The specific structure diagram of the feeding point is as Figure 6 shown. There is a rectangular slit 108 near the bending point, which is the chip installation location. Then, by adjusting the position of the tag chip, the best matching frequency can be better selected. The shape of the bent metal wire can be a "ji" character shape, and the size of each segment can be adjusted according to actual needs, and no more explanations will be given here. It is easy to understand that the straight metal wire and the bent metal wire can be two independently processed components connected together, or they can be a straight line, with one end bent to form a bent metal wire and the remaining part being a straight line.

[0036] Among them, by slotting, the current distribution on the metal radiation patch is changed. The rectangular slot and the "L"-shaped slot can make the antenna form meander lines. At the same time, due to the "L"-shaped slot, the metal patch forms a coupling structure, which can generate a large inductance value for the antenna. Due to the impedance characteristics of the chip, to achieve conjugate impedance matching, the antenna must satisfy the characteristics of low resistance and high inductance. Then, by adjusting the size and position of the slot, this specific high inductance can be satisfied. The third and fourth slots can also change the current distribution and increase the current path in the same way. Here, mainly small-range adjustments are made to get closer to the conjugate impedance value. That is to say, by setting the first and second slot structures with larger sizes, conjugate impedance matching is achieved, and by setting the third and fourth slot structures with smaller sizes, the conjugate impedance is adjusted, ultimately making the inductance value generated by the antenna closer to the conjugate impedance value.

[0037] The slots opened in the present invention are rectangular slots, and other-shaped slots can also be used to make the antenna design flexible. However, the rectangular slot is the easiest to control. Mainly, adjusting the rectangular slot involves two variables, length and width, which are intuitive and easy to control. If other-shaped slots are used, there are too many variables and it is not easy to control.

[0038] As Figure 4 shown, the label is characterized in that the antenna ground layer is a rectangular metal patch 301 existing in the "horizontal bar" of the "T"-shaped label, which has its own metal floor and can effectively reduce the influence of the metal surface on it.

[0039] The size of the "horizontal bar" of the intermediate dielectric layer 200 of the label is 98 mm × 26 mm × 0.2 mm, and the size of the "vertical bar" is 91 mm × 30 mm × 0.2 mm. The material is polyimide material with a dielectric constant of 3.5 and a loss tangent value of 0.008. As Figure 2 shown, at this thickness of 0.2 mm, the "vertical bar" of the "T"-shaped label where the chip exists is entirely placed between two adjacent batteries 20, bent at the connection of the "vertical bar" and the "horizontal bar", and the "horizontal bar" of the "T"-shaped label is attached to the side wall of the battery, so as to be able to realize sensing and monitoring in an extremely narrow environment with metal on both sides.

[0040] Using the flexible UHF RFID tag integrated with the battery unit provided by the present invention, an RFID tag can be configured for each battery unit, which is a way to realize the Battery Identity Global Passport (BIGP), improve the automation level of production and recycling, provide health management data for the entire life cycle of the battery, and construct the life data portraits of battery monomers, modules, and whole packs.

[0041] As Figure 7As shown, the antenna can generate a -10dB bandwidth from 876 MHz to 946 MHz, fully covering the latest domestic UHF RFID frequency band from 920 MHz to 925 MHz, and having a certain amount of extra bandwidth, ensuring the adaptability, stability, and feasibility of energy transmission during actual use.

[0042] As Figure 7 shown, the reflection coefficient of the tag antenna within this frequency band is at least -43 dB, and the center frequency is 920 MHz, ensuring good transmission of most of the antenna's energy and signal power, and also indicating good antenna impedance matching, guaranteeing stability during actual use.

[0043] As Figure 8 shown, the impedance of the tag antenna at 920 MHz is 14 + 120i, with good conjugate impedance matching and easy to adjust.

[0044] Prepare a UHF RFID tag with the following specific dimensions:

[0045] Metal patch layer (top layer): 98 mm × 24 mm × 0.2 mm, dielectric layer (middle layer)

[0046] 91 mm × 30 mm × 0.2 mm, ground layer: 92 mm × 26 mm × 0.3 mm, the width of the L-shaped slot structure (relative to the width direction of the metal patch layer) is 22.5 mm, the length is 33 mm, the slot width in the width direction is 2 mm, the size of the second slot structure is

[0047] 27.5 mm × 14 mm, the size of the third slot structure is 16.5 mm × 7.4 mm, the size of the fourth slot structure is 4.2 mm × 2 mm, the diameter of the straight metal wire is about 1 mm, the width of the bent metal wire is about 28 mm, the width of the chip installation position is about 1.4 mm, the horizontal bending length near the chip installation position is about 6.5 mm, and the horizontal bending lengths of the other two are about 4.8 mm.

[0048] Analyze the above UHF RFID tag, and the simulation results are as follows:

[0049] 1. Within the range where the S11 coefficient is lower than -10 dB, the tag antenna can generate a relatively wide bandwidth frequency band from 876 MHz to 946 MHz. This frequency band covers the latest domestic UHF RFID frequency band from 920 MHz to 925 MHz, and has a certain amount of extra bandwidth, ensuring the adaptability, stability, and feasibility of energy transmission during actual use.

[0050] 2. The impedance of the tag antenna at 920 MHz is 14 + 120i, with good impedance matching with the chip, and the impedance is easy to adjust through the slot structure.

[0051] 3. The reflection coefficient in this frequency band is as low as -43 dB at the center frequency of 920 MHz, ensuring good transmission of most of the antenna's energy and signal power. At the same time, it also shows that the antenna has good impedance matching, ensuring stability during actual use.

[0052] It should be understood that the application of the present invention is not limited to the above examples. For those of ordinary skill in the art, improvements or transformations can be made according to the above description, and all such improvements and transformations should fall within the protection scope of the appended claims of the present invention.

Claims

1. A battery cell integrated flexible UHF RFID tag, characterized in that: The flexible UHF RFID tag integrated with the battery unit is in a T-shape as a whole, and includes: The metal patch layer comprises a radiation patch body, a first slotted structure and a second slotted structure arranged on the radiation patch body; the first slotted structure is an L-shaped slotted structure, one end of the L-shaped slotted structure is located at the edge of the radiation patch body, and the other end is located inside the radiation patch body; the second slotted structure is located inside the L-shaped slotted structure; A grounding layer, the metal patch layer is arranged on the grounding layer; The dielectric layer comprises a flexible substrate, a metal wire and a chip arranged in the flexible substrate; the metal wire consists of a straight metal wire and a curved metal wire connected to the straight metal wire; an end of the straight metal wire close to the curved metal wire is provided with a mounting position for mounting the chip; one end of the dielectric layer is fixed between the ground layer and the dielectric layer, and one end of the straight metal wire is connected to the metal patch layer; the curved metal wire is away from the ground layer.

2. The battery cell integrated flexible UHF RFID tag according to claim 1, characterized in that: The battery unit integrated flexible UHF RFID tag further includes a third slot structure; the third slot structure is entirely located in the radiation patch body and is far away from the second slot structure.

3. The battery cell integrated flexible UHF RFID tag according to claim 2, characterized in that: The battery unit integrated flexible UHF RFID tag further includes a fourth slot structure; the fourth slot structure is located between the second slot structure and the third slot structure, and one end of the fourth slot structure is located at the edge of the radiation patch body.

4. The battery cell integrated flexible UHF RFID tag according to claim 2, characterized in that: The orthographic projections of the second slotted structure and the third slotted structure are rectangles.

5. The battery cell integrated flexible UHF RFID tag according to claim 4, characterized in that: The area of ​​the second slot structure is greater than the area of ​​the third slot structure.

6. The battery cell integrated flexible UHF RFID tag according to claim 5, characterized in that: The orthographic projection of the fourth slotted structure is a rectangle, and the area of ​​the fourth slotted structure is smaller than the area of ​​the third slotted structure.

7. The battery cell integrated flexible UHF RFID tag according to claim 1, characterized in that: The material of the flexible substrate is selected from polyimide,,,.

8. The battery cell integrated flexible UHF RFID tag according to claim 1, characterized in that: The bent metal wire is in a "J"-shaped structure.

9. The battery cell integrated flexible UHF RFID tag according to claim 1, characterized in that: The thickness of the dielectric layer is less than or equal to 0.2 mm.

10. The battery cell integrated flexible UHF RFID tag according to any one of claims 1 to 9, characterized in that: The flexible UHF RFID tag integrated in the battery unit generates a frequency band of 876-946 MHz.

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