A multi-layer composite planar thermal and electrical conductive structure

Abstract

The present invention discloses a multi-layer composite planar heat-conducting and electrically conductive structure, comprising: a metal conductive and heat-conducting layer and a non-metal conductive and heat-conducting layer, wherein the metal conductive and heat-conducting layer and the non-metal conductive and heat-conducting layer are alternately superimposed and distributed in sequence, the non-metal conductive and heat-conducting layer is provided with a through hole, and a conductive and heat-conducting connector penetrating the through hole is provided between the metal conductive and heat-conducting layers above and below the non-metal conductive and heat-conducting layer, and the number of the metal conductive and heat-conducting layers is at least 2 layers. Through the above manner, the multi-layer composite planar heat-conducting and electrically conductive structure described in the present invention uses the metal conductive and heat-conducting layer to clamp the non-metal conductive and heat-conducting layer, thereby avoiding damage of the non-metal conductive and heat-conducting layer during use due to brittleness, and improving the planar heat-conducting and electrically conductive effect. In particular, a through hole is designed in the non-metal conductive and heat-conducting layer, and a conductive and heat-conducting connector is used to penetrate the through hole, thereby realizing electrical connection, thermal connection and structural locking of the upper and lower metal conductive and heat-conducting layers.

Description

Technical Field

[0001] The invention relates to the field of planar heat-conducting and electrical-conducting materials, and in particular to a multi-layer composite planar heat-conducting and electrical-conducting structure. Background Art

[0002] When it comes to the selection of conductive materials for multi-power busbars, copper, aluminum and nickel materials are widely used. Copper conductors, in particular, have a large thermal conductivity, good thermal conductivity, and relatively small resistivity, resulting in less power loss. Therefore, copper conductors are given priority in busbar material selection.

[0003] In the process of grouping power batteries, a bus is needed to electrically connect the individual lithium batteries in series and parallel. The planar conductivity of the bus is related to the uniformity of the electric field of the module or battery pack. At the same time, the planar thermal conductivity of the bus also affects the thermal field uniformity of the module or battery pack. Due to the compact size of the battery pack, the thickness design of the bus is subject to certain restrictions. Therefore, the planar conductive and thermal conductive cross-sectional area of ​​the bus is also limited. When the battery is working, the current and heat flow are mostly collected on the bus and exported. Therefore, higher planar thermal conductivity and electrical conductivity requirements are put forward for the bus with limited thickness.

[0004] Ordinary buses are mostly made of single metal or composite metal structure materials, and their planar electrical and thermal conductivity is positively correlated with the planar electrical and thermal conductivity coefficient of the material under the condition of a certain electrical and thermal conductivity area. To improve the planar thermal conductivity of the bus, the planar thermal conductivity of the composite bus can be further improved by adding a non-metallic thermal and electrical conductive layer with a higher planar thermal conductivity coefficient while retaining the high planar conductivity and easy forming characteristics of the metal layer. The utility model patent with application number 201120482906.3 discloses a copper-carbon composite thermal conductive plate, which uses a carbon thermal conductive layer to improve the thermal conductivity. However, this method adds an adhesive layer in the Z-axis direction, which is an insulating material, resulting in the separation of the electrical and thermal planar conduction of the copper layer and the planar thermal conduction of the carbon layer, and the result is:

[0005] 1. The carbon layer has little contribution to the overall planar conductivity;

[0006] 2. The extremely thin adhesive layer has a unidirectional planar fastening force on the carbon layer. On the other side of the carbon layer where the adhesive layer is not applied, the carbon layer is easily broken due to bending of the material, thereby blocking the planar heat conduction channel of the carbon layer and causing a significant reduction in the planar heat conduction effect. This needs to be improved. Summary of the invention

[0007] The main technical problem solved by the present invention is to provide a multi-layer composite planar thermal and electrical conductive structure to improve the planar thermal conductivity effect and ensure the overall structural strength, easy processing and forming, and thermal and electrical conductivity stability.

[0008] In order to solve the above technical problems, a technical solution adopted by the present invention is: to provide a multi-layer composite planar thermal conductive structure, including: a metal conductive thermal conductive layer and a non-metallic conductive thermal conductive layer, the metal conductive thermal conductive layer and the non-metallic conductive thermal conductive layer are alternately stacked and distributed up and down and electrically and thermally connected up and down, the non-metallic conductive thermal conductive layer is provided with a through hole, and a conductive thermal conductive connector penetrating the through hole is provided between the metal conductive thermal conductive layer above and below the non-metallic conductive thermal conductive layer, the number of the metal conductive thermal conductive layers is at least 2, and the planar thermal conductivity of the non-metallic conductive thermal conductive layer is greater than the planar thermal conductivity of the metal conductive thermal conductive layer.

[0009] In a preferred embodiment of the present invention, the top surface and the bottom surface are respectively metal conductive and thermal conductive layers, and the metal conductive and thermal conductive layers include but are not limited to metal sheets, metal wire braided layers and metal powder pressed layers.

[0010] In a preferred embodiment of the present invention, the metal conductive and thermal conductive layer includes but is not limited to a copper metal layer, an aluminum metal layer and a nickel metal layer.

[0011] In a preferred embodiment of the present invention, the through hole array is distributed on the non-metallic thermal and electrical conductive layer.

[0012] In a preferred embodiment of the present invention, the non-metallic thermally conductive and electrically conductive layer is a single-layer or multi-layer carbon-based composite thermally conductive and electrically conductive layer, and the carbon-based composite thermally conductive and electrically conductive layer includes but is not limited to thermally conductive and electrically conductive graphite film or graphene, and the graphene sheets are grown, coated, clamped or glued between the metal conductive and thermally conductive layers.

[0013] In a preferred embodiment of the present invention, the non-metallic thermally and electrically conductive layer is surrounded by a metal edging that connects the metal electrically conductive and thermally conductive layer above and below it.

[0014] In a preferred embodiment of the present invention, the metal conductive and heat-conductive layer and the metal edging are made of the same or different thermally conductive and electrical materials.

[0015] In a preferred embodiment of the present invention, a curable conductive adhesive is provided between the metal conductive and thermal conductive layer and the non-metal conductive and thermal conductive layer to participate in thermal and electrical conduction in the plane and thickness directions.

[0016] In a preferred embodiment of the present invention, the metal conductive and thermally conductive layer, the conductive and thermally conductive connector and the non-metallic conductive and thermally conductive layer are fixed by vacuum pressing or sintering, and as a whole participate in thermal and electrical conduction in the plane and thickness directions.

[0017] In a preferred embodiment of the present invention, the electrically conductive and thermally conductive connecting member is a regular or irregular column structure.

[0018] The beneficial effects of the present invention are as follows: a multi-layer composite planar thermal conductive structure pointed out by the present invention adopts a multi-layer composite structure, and uses a metal conductive thermal conductive layer with better toughness to clamp or bond a non-metallic thermal conductive layer with a higher planar thermal conductivity coefficient to form an integrated multi-layer composite structure, which is beneficial to thinning the thickness of the non-metallic thermal conductive layer, and can avoid the non-metallic thermal conductive layer from being damaged (forming separation) during preparation or use due to brittleness, thereby causing its planar thermal conductive and conductive path to be blocked, and can also improve the overall thermal conductive and conductive effect of the composite structure in the planar direction. In particular, a through hole is designed in the non-metallic thermal conductive layer, and a conductive thermal conductive connector is used to penetrate the through hole to realize the connection between the upper and lower metal conductive thermal conductive layers, thereby realizing the electrical connection, thermal connection and structural locking of the upper and lower metal conductive thermal conductive layers, thereby improving the overall structural strength of the composite structure, avoiding deformation and delamination problems under high temperature, and having a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0020] Figure 1 It is a structural schematic diagram of a preferred embodiment of a multi-layer composite planar heat-conducting and electrical-conducting structure of the present invention;

[0021] Figure 2 yes Figure 1 A top view of the metal conductive and thermal conductive layer;

[0022] Figure 3 yes Figure 1 A top view of the non-metallic thermal and electrical conductive layer;

[0023] Figure 4 It is a structural schematic diagram of another preferred embodiment of a multi-layer composite planar heat-conducting and electrical-conducting structure of the present invention;

[0024] Figure 5 It is a structural schematic diagram of another preferred embodiment of a multi-layer composite planar thermal and electrical conductive structure of the present invention. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] See also Figure 1~Figure 5 , the embodiment of the present invention includes:

[0027] like Figure 1 The multi-layer composite planar heat-conducting and conductive structure shown includes: a metal conductive heat-conducting layer 1 and a non-metallic conductive heat-conducting and conductive layer 2, wherein the metal conductive heat-conducting layer 1 and the non-metallic conductive heat-conducting and conductive layer 2 are alternately stacked and distributed up and down, and the number of the metal conductive heat-conducting layers 1 is at least 2 layers, and the top and bottom surfaces of the multi-layer composite planar heat-conducting and conductive structure are respectively the metal conductive heat-conducting and conductive layers 1, so as to facilitate the welding of the surface of the multi-layer composite planar heat-conducting and conductive structure with the battery or other components, ensure the stability of the conductive connection, and strengthen

[0028] The metal conductive and thermally conductive layer 1 includes but is not limited to a copper metal layer, an aluminum metal layer and a nickel metal layer. Considering the thermal and electrical conductivity and cost-effectiveness, the copper conductive layer is mainly used, including a metal sheet made of pure copper or copper alloy material, a metal wire braided layer and a metal powder pressed layer. The non-metallic thermally conductive and conductive layer 2 is a single-layer or multi-layer carbon-based composite thermally conductive and conductive layer. The carbon-based composite thermally conductive and conductive layer includes but is not limited to a thermally conductive and conductive graphite film or graphene, which improves the surface thermal conductivity and uses the metal conductive and thermally conductive layer 1 with better toughness to protect the non-metallic thermally conductive and conductive layer 2. Among them, the multi-layer carbon-based composite thermally conductive and conductive layer is preferably a graphite film. Graphite film is a composite thermally conductive and heat dissipating material. It has a unique grain orientation and a lamellar structure that can adapt well to any surface and can adapt to uniform heat conduction on any surface. It generally has an ultra-high thermal conductivity in the range of 150-1500 W / mK in the plane, and as the graphite film thickens, the thermal conductivity increases in direct proportion. Unlike graphene, the increase in thermal conductivity is not obvious when the graphene is thickened.

[0029] like Figure 3 As shown, a through hole 5 is provided on the non-metallic thermally conductive layer 2, and a conductive thermally conductive connector 3 penetrating the through hole 5 is provided between the metal conductive thermally conductive layer 1 above and below the non-metallic thermally conductive layer 2. The conductive thermally conductive connector 3 is a regular or irregular columnar structure, and can be made of the same material as the metal conductive thermally conductive layer 1 to ensure the conductive effect. Of course, different metal thermally conductive materials can also be used.

[0030] An array of through holes 5 is distributed on the non-metallic thermally conductive layer 2, and the upper and lower metal thermally conductive layers 1 are tightened through the array's conductive thermal connectors 3, thereby achieving electrical connection, thermal connection and structural locking between the upper and lower metal thermally conductive layers, and clamping the non-metallic thermally conductive layer 2 by the metal thermally conductive layer 1, which has a good anti-seismic effect and improves the structural stability of the non-metallic thermally conductive layer 2.

[0031] There are two ways to connect the metal conductive and thermal conductive layer 1 and the non-metal conductive and thermal conductive layer 2:

[0032] The first type is that a conductive adhesive is provided between the metal conductive and thermal conductive layer 1 and the non-metal conductive and thermal conductive layer 2, and the metal conductive and thermal conductive layer 1 and the non-metal conductive and thermal conductive layer 2 are connected by the conductive adhesive, which is suitable for use in places where the temperature is not high, and the conductive adhesive participates in the heat and electricity conduction in the plane and thickness directions;

[0033] Second, the metal conductive and thermally conductive layer 1, the conductive and thermally conductive connector 3 and the non-metallic conductive and thermally conductive layer 2 are fixed by vacuum pressing or sintering. When the layered pressing and sintering technology is adopted, the pressing is performed through a mold, the structure is firm, and the high temperature resistance effect is good during use.

[0034] Embodiment 1:

[0035] like Figure 1~Figure 3 As shown, the metal conductive thermal conductive layer 1 is composed of two layers, and the non-metal conductive thermal conductive layer 2 is composed of one layer. Keeping the non-metal conductive thermal conductive layer 2 clamped by the metal conductive thermal conductive layer 1 is beneficial to thinning the thickness of the non-metal conductive thermal conductive layer 2, improving the thermal conductivity and structural stability, and avoiding damage of the non-metal conductive thermal conductive layer 2 during preparation and use due to its brittleness.

[0036] Embodiment 2:

[0037] like Figure 5 As shown, the metal conductive and thermal conductive layer 1 has 4 layers, and the non-metal conductive and thermal conductive layer 2 has 3 layers. Increasing the number of non-metal conductive and thermal conductive layers 2 is conducive to further reducing the thickness of each non-metal conductive and thermal conductive layer 2, making the non-metal conductive and thermal conductive layer 2 extremely thin and having a better thermal conductivity. Since the non-metal conductive and thermal conductive layer 2 has a higher planar thermal conductivity and electrical conductivity, the composite structure as a whole improves the planar thermal conductivity and electrical conductivity. Since some busbars are very thin and the longitudinal heat conduction distance is very short, the thermal conductivity coefficient has little effect on the longitudinal thermal conductivity, but the heat conduction distance in the planar direction is long and the heat conduction cross-sectional area is small. Therefore, in order to improve its planar thermal conductivity, a non-metal conductive and thermal conductive layer 2 with a higher planar thermal conductivity must be installed, and the planar thermal conductivity is improved by using multiple layers of thermally conductive and electrically conductive carbon materials.

[0038] Embodiment 3:

[0039] like Figure 4 As shown, the non-metallic thermally conductive layer 2 is surrounded by metal edging 4 that connects the metal conductive thermally conductive layer 1 above and below it. The metal conductive thermally conductive layer 1 and the metal edging 4 are made of the same or different thermally conductive materials and are fixed by vacuum crimping or sintering. The metal edging 4 is used to protect the non-metallic thermally conductive layer 2 around to improve the seismic and impact resistance.

[0040] In summary, the multi-layer composite planar thermal and electrically conductive structure pointed out in the present invention adopts multi-layer composite technology, improves the planar thermal conductivity effect through the non-metallic thermal and electrically conductive layer, and ensures the overall structural stability. The overall thermal and electrically conductive structure participates in the planar and thickness directions, has high efficiency, and is safer to use in high temperature environments.

[0041] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A multi-layer composite planar thermal and electrical conductive structure, characterized in that: include: A metal conductive and thermally conductive layer and a non-metallic conductive and thermally conductive layer, wherein the metal conductive and thermally conductive layer and the non-metallic conductive and thermally conductive layer are alternately stacked and distributed in sequence, a through hole is provided on the non-metallic conductive and thermally conductive layer, a conductive and thermally conductive connector penetrating the through hole is provided between the metal conductive and thermally conductive layer above and below the non-metallic conductive and thermally conductive layer, and electrical connection, thermal connection and structural locking of the upper and lower metal conductive and thermally conductive layers are achieved through the conductive and thermally conductive connector, the number of the metal conductive and thermally conductive layers is at least 2, the planar thermal conductivity of the non-metallic conductive and thermally conductive layer is greater than the planar thermal conductivity of the metal conductive and thermally conductive layer, and a conductive adhesive is provided between the metal conductive and thermally conductive layer and the non-metallic conductive and thermally conductive layer.

2. The multi-layer composite planar thermal and electrical conductive structure according to claim 1, characterized in that: The top surface and the bottom surface are respectively metal conductive and heat conductive layers, and the metal conductive and heat conductive layers include one or more of metal sheets, metal wire braided layers, or metal powder pressed layers.

3. The multi-layer composite planar thermal and electrical conductive structure according to claim 1, characterized in that: The metal conductive and thermal conductive layer includes one or more of a copper metal layer, an aluminum metal layer, or a nickel metal layer.

4. The multi-layer composite planar thermal and electrical conductive structure according to claim 1, characterized in that: The through hole array is distributed on the non-metallic thermal and electrical conductive layer.

5. The multi-layer composite planar thermal and electrical conductive structure according to claim 1, characterized in that: The non-metallic thermally conductive and electrically conductive layer is a single-layer or multi-layer carbon-based composite thermally conductive and electrically conductive layer, and the carbon-based composite thermally conductive and electrically conductive layer includes one or more thermally conductive and electrically conductive graphite films or graphenes.

6. The multi-layer composite planar thermal and electrical conductive structure according to claim 1, characterized in that: The non-metallic heat-conducting and electrically conductive layer is surrounded by a metal edging that connects the metal heat-conducting and electrically conductive layers above and below it.

7. The multi-layer composite planar thermal and electrical conductive structure according to claim 6, characterized in that: The metal conductive and heat conductive layer and the metal edging are made of the same or different thermal and electrical conductive materials.

8. The multi-layer composite planar thermal and electrical conductive structure according to claim 1, characterized in that: The metal conductive and heat-conductive layer, the conductive and heat-conductive connector and the non-metal conductive and heat-conductive layer are fixed by vacuum pressing or sintering.

9. The multi-layer composite planar thermal and electrical conductive structure according to claim 1, characterized in that: The electrically conductive and thermally conductive connecting member is a regular or irregular column structure.

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