Integrated pressure-sensitive heating film

Abstract

The utility model provides a kind of integrated pressure-sensing heating film, include structure: flexible dielectric layer;The interdigitated electrode layer of attachment in the dielectric layer one side, the interdigitated electrode respectively leads out electric property, a electrode electrically grounded, another root adds voltage;The electrode array layer of attachment in the dielectric layer other side, evenly distribute in flexible dielectric layer each area and lead to port, respectively test each area and the potential difference change of ground electrode in interdigitated electrode layer;PPTC film layer is attached on the interdigitated electrode layer, and realize surface heating by the potential difference of the interdigitated electrode conduction;Heat-conducting insulating film layer is respectively attached on the PPTC film layer and the electrode array layer.The utility model compactly integrates self-limiting temperature heating function PPTC device and capacitive pressure sensor, flexible and foldable, heating function and area pressure monitoring function integration degree is high, help the safety and light weight of power battery.

Description

Technical Field

[0001] This utility model relates to the field of functional materials technology, and in particular to heating films and pressure sensors for lithium battery packs. Background Technology

[0002] The continuous improvement in the capacity and cycle performance of power batteries in the new energy vehicle industry brings significant challenges to safety performance. Safety is a crucial standard for evaluating the performance of new energy vehicles. The charging and discharging performance of lithium batteries is extremely sensitive to ambient temperature, especially in low-temperature environments. Electric vehicles powered by lithium battery packs may experience battery charging and discharging failures or extremely low charging and discharging capacities, affecting normal vehicle starting. The starting current required by a car's starter motor increases with lower temperatures; therefore, most automotive power batteries are equipped with electric heating devices as standard. Polymer-based PTC composite materials (PPTC) are composed of a polymer matrix and conductive fillers. Compared to traditional heating wires, PPTC can withstand lower temperatures, providing higher starting heating power and suitable, safer thermal characteristics, thus well meeting the temperature control requirements of automotive power batteries. Power battery modules require real-time safety status monitoring during operation and periodic checks even when not in operation. The expansion and deformation of the PACK surface are related to risk factors such as internal pressure overheating and gas expansion, and are a crucial component of safety monitoring. Sensitive detection of the distribution of pressure changes in the battery PACK requires numerous distributed sensors, significantly increasing space requirements and weight. Therefore, it is essential to optimize and comprehensively design to address these issues. Summary of the Invention

[0003] In view of the shortcomings of the prior art described above, the purpose of this utility model is to provide an integrated pressure-sensitive heating film to solve the integrated design problem of low-temperature start-up heating and thermal expansion monitoring of power battery PACK in the prior art.

[0004] To achieve the above and other related objectives, this utility model provides an integrated pressure-sensitive heating film: comprising the following structure:

[0005] 1) Flexible dielectric layer;

[0006] 2) An interdigitated electrode layer attached to one side of the dielectric layer, wherein each interdigitated electrode is electrically led out, one electrode is electrically grounded, and the other is energized;

[0007] 3) An electrode array layer attached to the other side of the dielectric layer is uniformly distributed in each region of the flexible dielectric layer and led out to the port. The potential difference between each region and the ground electrode in the interdigitated electrode layer is tested respectively.

[0008] 4) The PPTC film layer attached to the interdigitated electrode layer achieves surface heating through the potential difference of the interdigitated electrodes;

[0009] 5) Thermally conductive and insulating film layers are respectively attached to the PPTC film layer and the electrode array layer.

[0010] Optionally, the matrix material of the flexible dielectric layer is one of porous PDMS, TPU, PVDF, or P(VDF-TrFE).

[0011] Optionally, the PPTC film layer is a conductive and flame-retardant film layer with a PTC transition temperature of 60~100℃ and a flame retardant rating of V0.

[0012] Optionally, the electrodes of the interdigitated electrode layer and the electrode array layer are one of copper electrodes, aluminum electrodes, and nickel electrodes.

[0013] Optionally, the thermally conductive insulating film layer is a flexible insulating film layer with a thermal conductivity greater than 1 W / mK.

[0014] The method of using the integrated pressure-sensitive heating film of this utility model is as follows: the integrated pressure-sensitive heating film PPTC side is attached to the lithium-ion battery PACK, and heating is achieved by energizing the PPTC film layer through interdigitated electrodes. The local expansion of the PACK is monitored by real-time testing of the potential difference changes between the electrodes in each region of the electrode array layer and the ground electrode in the interdigitated electrode layer.

[0015] As described above, the integrated pressure-sensitive heating film of this utility model has the following beneficial effects: it compactly integrates a PPTC device with self-limiting temperature heating function and a capacitive pressure-sensitive device, is flexible and bendable, and can be easily applied to the surface of the battery pack. The PPTC safely heats the battery pack under low-temperature conditions, the porous composite dielectric layer forms an electret that can sensitively respond to pressure changes, and the interdigitated electrodes serve as both heating electrodes and reference electrodes for the capacitive pressure sensor. Local expansion stress is sensed through electrode alignment. The heating function and regional pressure monitoring function have a high degree of integration, which contributes to the safety and lightweighting of the power battery. Attached Figure Description

[0016] Figure 1 The diagram shown is a structural schematic of an integrated pressure-sensitive heating film according to this utility model.

[0017] Figure 2 The diagram shown is a structural schematic of an integrated pressure-sensitive heating film interdigitated electrode layer according to this utility model.

[0018] Figure 3 The diagram shown is a structural schematic of an integrated pressure-sensitive heating film electrode array layer according to this utility model.

[0019] Component designation explanation:

[0020] 1 Flexible dielectric layer

[0021] 2. Interdigitated electrode layer

[0022] 3 Electrode Array Layer

[0023] 4 PPTC film layer

[0024] 5 Thermally conductive insulating film layer Detailed Implementation

[0025] The following specific embodiments illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model.

[0026] See Figures 1-3 It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of this utility model. The illustrations only show the components related to this utility model and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0027] This embodiment provides an integrated pressure-sensitive heating film, the structure of which is as follows: Figure 1 As shown.

[0028] The system comprises a flexible dielectric layer 1, an interdigitated electrode layer 2 attached to one side of the flexible dielectric layer 1, and an electrode array layer 3 attached to the other side of the dielectric layer 1. The matrix material of the flexible dielectric layer is one of porous PDMS, TPU, PVDF, or P(VDF-TrFE). The structures of the interdigitated electrode layer 2 and the electrode array layer 3 are as follows: Figure 2 and Figure 3 As shown, the electrodes can be copper, aluminum, or nickel. The intercalation electrodes 2 are electrically connected, with one electrode electrically grounded and the other voltage-applied. The electrode array layer 2 is uniformly distributed across each region of the flexible dielectric layer 1 and leads to a port, allowing for the measurement of the potential difference between each region and the grounded electrode in the intercalation electrode layer 1. The PPTC film layer 4 is attached to the intercalation electrode layer 1, achieving surface heating through the potential difference between the intercalation electrodes. The PPTC film layer is a conductive and flame-retardant film layer with a PTC transition temperature of 60~100℃ and a flame retardant rating of V0. A thermally conductive and insulating film layer 5 is attached to both the PPTC film layer 3 and the electrode array layer 3, and is a flexible insulating film layer with a thermal conductivity greater than 1W / mK.

[0029] The method of using the integrated pressure-sensitive heating film of this utility model is as follows: the integrated pressure-sensitive heating film PPTC side is attached to the lithium-ion battery PACK, and heating is achieved by energizing the PPTC film layer through interdigitated electrodes. The local expansion of the PACK is monitored by real-time testing of the potential difference changes between the electrodes in each region of the electrode array layer and the ground electrode in the interdigitated electrode layer.

[0030] In summary, the integrated pressure-sensitive heating film and its manufacturing method of this utility model have the following beneficial effects: It compactly integrates a PPTC device with self-limiting temperature heating function and a capacitive pressure-sensitive device; it is flexible and bendable, allowing for easy application to the battery pack surface. The PPTC safely heats the battery pack under low-temperature conditions; the porous composite dielectric layer forms an electret that sensitively responds to pressure changes; the interdigitated electrodes simultaneously serve as heating electrodes and reference electrodes for the capacitive pressure sensor; and local expansion stress is sensed through electrode alignment. The high integration of heating and regional pressure monitoring functions contributes to the safety and lightweight design of power batteries. Therefore, this utility model effectively overcomes the shortcomings of existing technologies and possesses high industrial value.

[0031] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. An integrated pressure-sensitive heating film, characterized by: Includes structure: 1) Flexible dielectric layer; 2) An interdigitated electrode layer attached to one side of the dielectric layer, wherein each interdigitated electrode is electrically led out, one electrode is electrically grounded, and the other is energized; 3) An electrode array layer attached to the other side of the dielectric layer is uniformly distributed in each region of the flexible dielectric layer and led out to the port. The potential difference between each region and the ground electrode in the interdigitated electrode layer is tested respectively. 4) The PPTC film layer attached to the interdigitated electrode layer achieves surface heating through the potential difference of the interdigitated electrodes; 5) Thermally conductive insulating film layers are respectively attached to the PPTC film layer and the electrode array layer.

2. The integrated pressure-sensitive heating film according to claim 1, wherein: The matrix material of the flexible dielectric layer is one of porous PDMS, TPU, PVDF, or P(VDF-TrFE).

3. The integrated pressure-sensitive heating film of claim 1, wherein: The PPTC film layer is a conductive and flame-retardant film layer with a PTC transition temperature of 60~100℃ and a flame retardant rating of V0.

4. The integrated pressure-sensitive heating film according to claim 1, characterized in that: The electrodes of the interdigitated electrode layer and the electrode array layer are one of copper electrodes, aluminum electrodes, and nickel electrodes.

5. The integrated pressure-sensitive heating film according to claim 1, characterized in that: The thermally conductive insulating film layer is a flexible insulating film layer with a thermal conductivity greater than 1 W / mK.

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