Expansion force detection device

Abstract

The utility model provides an expansive force detection device. The expansive force detection device comprises an upper flexible buffer layer, a film sensor body, a lower flexible buffer layer and an acquisition interface, the film sensor body comprises an upper silk-screen electrode layer, an upper double-faced adhesive tape bonding layer, an upper silk-screen piezoresistive sensing layer, a lower silk-screen piezoresistive sensing layer, a lower double-faced adhesive tape bonding layer and a lower silk-screen electrode layer; the acquisition interface is provided with an acquisition end and a connecting end, the acquisition end is electrically connected with the film sensor body, and the acquisition end is used for being connected with an acquisition device. The upper flexible buffer layer and the lower flexible buffer layer are arranged on the film sensor body, so that fastening force can be buffered and balanced when a battery pack is installed, and expansion force sensing points distributed in an array manner are uniformly pressed; meanwhile, due to the action of the flexible buffer layer, when the expansion position of the battery is located at the periphery of the sensing point, a changing expansion force signal can be identified, the detection capability of the thin film sensor body is improved, the density of the sensing point or the area of the sensing point can be reduced, and the manufacturing cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of battery expansion force detection, in particular to an expansion force detection device. Background Art

[0002] Lithium-ion batteries are one of the most widely used energy storage batteries, favored for their high energy density, long life, and excellent environmental performance. When used in energy storage applications, lithium-ion batteries face stress from two main sources. First, lithium-ion batteries are typically assembled into battery packs, often in series and parallel configurations. Fixings are required to apply a certain degree of pressure to the battery pack to maintain its stability. Second, during normal charge and discharge cycles, the pressure generated by battery expansion due to lithium-ion intercalation and deintercalation, as well as side reactions, leads to internal gassing and the formation of SEI films. Appropriate pressure can strengthen contact between the positive and negative electrodes and the separator, improve the charge and discharge reaction interface, and reduce internal resistance and polarization, thereby enhancing cycling stability and high-rate charge and discharge performance. However, excessive pressure can damage the pore structure of the electrode and separator, deteriorate the reaction interface, and rapidly degrade battery capacity. In severe cases, this can cause internal short circuits and create risks such as thermal runaway. Therefore, it is necessary to monitor and provide early warning of expansion forces within energy storage battery packs.

[0003] Currently, common battery pressure expansion force detection devices generally include a thin film pressure sensor and its corresponding collector. The thin film pressure sensor usually has a multi-sensing point structure distributed in an array. The pressure sensing points of different sizes and densities are designed according to the size and area of ​​the battery pack and comprehensive consideration of cost.

[0004] Existing thin-film pressure sensors are composed of upper and lower electrode layers, upper and lower sensing layers, an isolation and bonding layer, and a packaging layer. However, battery packs usually have rigid shells. During use, due to the presence of the isolation and bonding layer, a considerable fastening force is required to fasten adjacent battery packs and tightly fit them with the thin-film pressure sensor to generate a measurable signal. Excessive fastening force may cause excessive squeezing of the battery pack, leading to battery damage. At the same time, the flatness and levelness of the battery pack shell will affect the accuracy of the measurement data of the thin-film pressure sensor. Utility Model Content

[0005] Based on this, in order to solve the problems in the prior art that the tightening force is difficult to control and the accuracy of the expansion force detection is affected by the tightening process, the utility model provides an expansion force detection device, and its specific technical solution is as follows:

[0006] An expansion force detection device includes an upper flexible buffer layer, a thin film sensor body, a lower flexible buffer layer, and an acquisition interface; the thin film sensor body includes an upper silk-screened electrode layer, an upper double-sided adhesive layer, an upper silk-screened piezoresistive sensing layer, a lower silk-screened piezoresistive sensing layer, a lower double-sided adhesive layer, and a lower silk-screened electrode layer; the acquisition interface is provided with a collection end and a connection end, the collection end is electrically connected to the thin film sensor body, and the collection end is used to connect to a collector.

[0007] The above-mentioned expansion force detection device, by providing two upper and lower flexible buffer layers on the thin film sensor body, can buffer and balance the tightening force when the upper battery pack and the lower battery pack are installed, so that the expansion force sensing points distributed in the array are evenly compressed; at the same time, due to the effect of the flexible buffer layer, the changing expansion force signal can also be identified when the battery expansion position is near the sensing point, thereby increasing the detection capability of the thin film sensor body, reducing the density or area of ​​the sensing points, and thus reducing manufacturing costs; in addition, the thin film sensor body is not provided with an isolation layer, and can sense the expansion force of the battery pack under conditions ranging from small pressure to large pressure, so that different battery packs can be set with similar tightening forces by different tightening degrees.

[0008] Furthermore, the acquisition end is an FPC port.

[0009] Furthermore, the FPC port is fixed to the upper silk-screen electrode layer and / or the lower silk-screen electrode layer by welding or bonding.

[0010] Furthermore, the upper silk-screen electrode layer and / or the lower silk-screen electrode layer is provided with an FPC area for electrically connecting to the FPC port.

[0011] Furthermore, the flexible buffer layer is a sheet of elastic material.

[0012] Furthermore, the elastic material sheet is a silicone elastic sheet, an EVA sheet, a TPU sheet, a chloroprene rubber sheet or a POE sheet.

[0013] Furthermore, the thickness of the elastic material sheet is 0.1 mm to 3 mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention can be further understood from the following description in conjunction with the accompanying drawings. The components in the figures are not necessarily drawn to scale, but rather the emphasis is placed on illustrating the principles of the embodiments. In different views, the same reference numerals designate corresponding parts.

[0015] Figure 1 This is an exploded view of the structure of the expansion force detection device according to one embodiment of the present utility model;

[0016] Figure 2 It is a structural diagram of the thin film sensor body described in one embodiment of the present utility model.

[0017] Description of reference numerals:

[0018] 1. Upper battery pack; 2. Upper flexible buffer layer; 3. Thin film sensor body; 4. Lower flexible buffer layer; 5. Lower battery pack; 6. Data acquisition interface;

[0019] 301, upper screen-printed electrode layer; 302, upper double-sided adhesive layer; 303, upper screen-printed piezoresistive sensing layer; 304, lower screen-printed piezoresistive sensing layer; 305, lower double-sided adhesive layer; 306, lower screen-printed electrode layer. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with its embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not limit the scope of protection of the present invention.

[0021] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly attached to the other element or there may be an intermediate element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of this invention are intended solely for the purpose of describing specific embodiments and are not intended to limit this invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0023] The "first" and "second" in the present invention do not represent specific quantities and orders, but are only used to distinguish names.

[0024] like Figure 1 and Figure 2As shown, an expansion force detection device in one embodiment of the present invention is disposed between an upper battery pack 1 and a lower battery pack 5 and includes an upper flexible buffer layer 2, a thin film sensor body 3, a lower flexible buffer layer 4, and a collection interface 6. The thin film sensor body 3 includes an upper silk-screened electrode layer 301, an upper double-sided adhesive layer 302, an upper silk-screened piezoresistive sensing layer 303, a lower silk-screened piezoresistive sensing layer 304, a lower double-sided adhesive layer 305, and a lower silk-screened electrode layer 306. The collection interface 6 includes a collection end and a connection end. The collection end is electrically connected to the thin film sensor body 3, and the collection end is used to connect to a collector. Specifically, the collection end is electrically connected to the expansion force detection area on the thin film sensor body 3.

[0025] The above-mentioned expansion force detection device, by providing two upper and lower flexible buffer layers on the thin film sensor body 3, can buffer and balance the tightening force when the upper battery pack 1 and the lower battery pack 5 are installed, so that the expansion force sensing points distributed in the array can be evenly compressed; at the same time, due to the effect of the flexible buffer layer, the changing expansion force signal can also be identified when the battery expansion position is around the sensing point, thereby increasing the detection capability of the thin film sensor body 3, and can reduce the density of the sensing points or the area of ​​the sensing points to reduce the manufacturing cost; in addition, the thin film sensor body 3 is not provided with an isolation layer, and can sense the expansion force of the battery pack under conditions of small pressure to large pressure, so that different battery packs can be set with similar tightening forces by different tightening degrees.

[0026] In one embodiment, the acquisition terminal is an FPC port. Specifically, the FPC port is an FPC gold finger interface, an FPC male port, or an FPC female port, and a ZIF connector is used between the FPC port and the collector. This facilitates connection between the FPC gold finger interface, the FPC male port, or the FPC female port and the collector, achieving electrical connectivity and signal acquisition.

[0027] In one embodiment, the FPC port is fixed to the upper silk-screen electrode layer 301 and / or the lower silk-screen electrode layer 306 by welding or bonding.

[0028] In one embodiment, the upper silk-screen electrode layer 301 and / or the lower silk-screen electrode layer 306 are provided with an FPC area for electrical connection to the FPC port. Thus, the FPC port typically has gold fingers formed of metal conductors that align with the pins of the socket to ensure a proper electrical connection; at the same time, no additional insertion force is required when inserting or removing the FPC port.

[0029] In one embodiment, the flexible buffer layer is an elastic material sheet. Thus, the elastic material sheet can buffer and balance the fastening force when the upper battery pack 1 and the lower battery pack 5 are installed, so that the expansion force sensing points distributed in the array are evenly compressed.

[0030] In one embodiment, the elastic material sheet is a silicone elastic sheet, EVA sheet, TPU sheet, neoprene sheet, or POE sheet. Due to the flexible buffer layer, the changing expansion force signal can be detected even when the battery expansion position is near the sensing point, thereby increasing the detection capability of the thin film sensor body 3 and reducing the density or area of ​​the sensing points, thereby lowering manufacturing costs.

[0031] In one embodiment, the thickness of the elastic material sheet is 0.1 mm to 3 mm. Specifically, the thickness of the elastic material sheet is adjusted according to different needs. When the thickness of the elastic material sheet is smaller, the sensing sensitivity is better, and when the thickness of the elastic material sheet is larger, the sensing buffer is better.

[0032] The working principle is as follows: the thin film sensor body 3 is not provided with an isolation layer. Under slight pressure, the silk-screen piezoresistive sensing layer can be in contact to generate an electrical signal, thereby improving the sensitivity and accuracy of expansion force detection. It can detect the expansion force of the battery pack under slight pressure to high pressure, and different battery packs can be set with similar tightening forces by different tightening degrees. At the same time, under different expansion force states, the electrical signal is transmitted to the collector in real time through the acquisition interface 6. The collector obtains the expansion force size and position information of different positions between the upper battery pack 1 and the lower battery pack 5 through calculation, thereby detecting and issuing early warning of the expansion force between the energy storage battery packs.

[0033] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0034] The above-described embodiments merely represent several implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present utility model patent shall be determined by the appended claims.

Claims

1. An expansion force detection device, characterized in that: It includes an upper flexible buffer layer, a thin film sensor body, a lower flexible buffer layer, and an acquisition interface; The thin film sensor body comprises an upper screen-printed electrode layer, an upper double-sided adhesive layer, an upper screen-printed piezoresistive sensing layer, a lower screen-printed piezoresistive sensing layer, a lower double-sided adhesive layer and a lower screen-printed electrode layer; The acquisition interface is provided with an acquisition end and a connection end. The acquisition end is electrically connected to the thin film sensor body, and the acquisition end is used to connect to the collector.

2. An expansion force detection device according to claim 1, characterized in that: The acquisition end is an FPC port.

3. An expansion force detection device according to claim 2, characterized in that: The FPC port is fixed on the upper silk-screen electrode layer and / or the lower silk-screen electrode layer by welding or bonding.

4. An expansion force detection device according to claim 2, characterized in that: The upper silk-screen electrode layer and / or the lower silk-screen electrode layer is provided with an FPC area for electrically connecting to the FPC port.

5. The expansion force detection device according to claim 1, characterized in that: The flexible buffer layer is an elastic material sheet.

6. An expansion force detection device according to claim 5, characterized in that: The elastic material sheet is a silicone elastic sheet, an EVA sheet, a TPU sheet, a chloroprene rubber sheet or a POE sheet.

7. An expansion force detection device according to claim 6, characterized in that: The thickness of the elastic material sheet is 0.1 mm to 3 mm.

Images