Ceramic thermal insulation

Abstract

A heat resistant electronic component is disclosed, comprising an electronic component covered by a layer of ceramic thermal insulation material containing lithium molybdate Li.sub.2MoO.sub.4. A process for manufacturing the heat resistant electronic component comprises obtaining ceramic thermal insulation material containing lithium molybdate Li.sub.2MoO.sub.4 in a mouldable form, optionally mixing the ceramic thermal insulation material with at least one additive, covering an electronic component with the material, shaping the material covering the electronic component into a desired form, and drying the desired form at a temperature of from 20° C. to 120° C.

Claims

1. A method of manufacturing a heat resistant electronic component comprising at least one of a battery, supercapacitor, electrolytic capacitor, light emitting diode, active component, sensor, and integrated circuit, the method comprising: obtaining lithium molybdate Li.sub.2MoO.sub.4 ceramic thermal insulation material in a mouldable form by using water and Li.sub.2MoO.sub.4 powder; optionally mixing the lithium molybdate Li.sub.2MoO.sub.4 ceramic thermal insulation material with at least one additive; covering an electronic component with the lithium molybdate Li.sub.2MoO.sub.4 ceramic thermal insulation material; shaping the material covering the electronic component into a desired form by removal of excess water present in the lithium molybdate Li.sub.2MoO.sub.4 ceramic thermal insulation material; and drying the desired form at a temperature of from 20° C. to 120° C. so that the shaped and dried form provides heat resistance to the electronic component.

2. The method according to claim 1, wherein the method is performed at a temperature of 150° C. or below.

3. The method according to claim 1, wherein the method comprises: 3D printing of the lithium molybdate Li.sub.2MoO.sub.4 ceramic thermal insulation material on top of the electronic component, molding of the lithium molybdate Li.sub.2MoO.sub.4 ceramic thermal insulation material on top of the electronic component, or pressure molding of the lithium molybdate Li.sub.2MoO.sub.4 ceramic thermal insulation material on top of the electronic component.

4. The method according to claim 1, wherein the method is performed at an atmospheric pressure.

5. The method according to claim 1, wherein the method is performed at a temperature of 20° C. to 150° C.

6. The method according to claim 1, wherein the lithium molybdate Li.sub.2MoO.sub.4 ceramic thermal insulation material is prepared at room temperature using water and Li.sub.2MoO.sub.4 powder.

7. The method according to claim 6, wherein the lithium molybdate Li.sub.2MoO.sub.4 ceramic thermal insulation material is densified by pressing and the removal of the excess water.

8. The method according to claim 1, wherein the lithium molybdate Li.sub.2MoO.sub.4 ceramic thermal insulation material is low temperature co-fired ceramic (LTCC) or ultra low temperature co-fired ceramic (ULTCC) material.

9. The method according to claim 1, wherein the lithium molybdate Li.sub.2MoO.sub.4 ceramic thermal insulation material includes one or more polymer materials mixed therewith.

10. The method according to claim 1, wherein the lithium molybdate Li.sub.2MoO.sub.4 ceramic thermal insulation material consists essentially of lithium molybdate Li.sub.2MoO.sub.4, and lacks any additives.

11. The method according to claim 1, wherein the lithium molybdate Li.sub.2MoO.sub.4 ceramic thermal insulation material that is obtained in the mouldable form is argillaceous material, paste, or slurry.

12. The method according to claim 1, wherein the lithium molybdate Li.sub.2MoO.sub.4 ceramic thermal insulation material that is obtained in the mouldable form has a viscosity suitable for moulding.

13. The method according to claim 1, wherein the electronic component is hermetically sealed by the lithium molybdate Li.sub.2MoO.sub.4 ceramic thermal insulation material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the following the invention will be described in greater detail by means of preferred embodiments with reference to the attached drawings, in which

(2) FIG. 1 illustrates exemplary heat resistant electronic components according to the invention.

DETAILED DESCRIPTION OF EMBODIMENTS

(3) The following embodiments are exemplary. Although the specification may refer to “an”, “one”, or “some” embodiment(s) in several locations, this does not necessarily mean that each such reference is to the same embodiment(s), or that the feature only applies to a single embodiment. Single features of different embodiments may also be combined to provide other embodiments. Furthermore, words “comprising”, “containing” and “including” should be understood as not limiting the described embodiments to consist of only those features that have been mentioned and such embodiments may contain also features/structures that have not been specifically mentioned.

(4) Li.sub.2MoO.sub.4 ceramics may be prepared at room-temperature based on utilization of a small amount of water with Li.sub.2MoO.sub.4 powder. The densification of the ceramic takes place by pressing and removal of excess water. Thus the shape and size of the ceramic object may be adjusted by controlling the mould dimensions and the amount of ceramic material. Post-processing may be applied at 120° C. to remove residual water from the object. However, the post-processing step is not mandatory, or the post-processing step may performed at a temperature lower than 120° C. The properties obtainable by the low temperature ceramic material may be similar to those achieved for Li.sub.2MoO.sub.4 ceramics fabricated by sintering at 540° C. An embodiment discloses thermal protection of an electronic component. An embodiment enables the manufacture of a thermally insulated electronic component. A structure is provided where the electronic component is thermally insulated against eventual heat exposure encountered during overmolding, and completely hermetically sealed (air-tight and/or gas-tight). Low temperature co-fired ceramic LTCC material, or ultra low temperature co-fired ceramic ULTCC material such as Li.sub.2MoO.sub.4, may be used as thermal insulation material for thermal protection of electronic components. A ceramic thermal insulation is provided that surrounds the electronic component. The ceramic thermal insulation material may contain lithium molybdate Li.sub.2MoO.sub.4. In addition to lithium molybdate, the thermal insulation material may contain one or more additives. The additive(s) may enhance the thermal insulation properties of the ceramic material. The additives may be in the form of particles that are mixed with the lithium molybdate. Examples of additives that may be used include polymers (such as PET or PI) or glass beads that decrease the thermal conductivity of the thermal insulation material. The additives may include air-filled polymer beads, air-filled glass beads, foaming agents, and/or porophores.

(5) In an embodiment, the ceramic thermal insulation material contains lithium molybdate Li.sub.2MoO.sub.4, but no additives or other ingredients.

(6) In an embodiment, instead of or in addition to lithium molybdate Li.sub.2MoO.sub.4, the ceramic thermal insulation material may contain NaCl, Na.sub.2Mo.sub.2O.sub.7, K.sub.2Mo.sub.2O, (LiBi).sub.0.5MoO.sub.4, KH.sub.2PO.sub.4, Li.sub.2WO.sub.4, Mg.sub.2P.sub.2O.sub.7, and/or V.sub.2O.sub.5, for example.

(7) The ceramic insulation material enables protecting the electronic component from heat/high temperatures, for example, during the manufacture of an electronic product. The ceramic insulation material has low thermal conductivity, and prevents excessive heat from reaching the electronic component, for example, during the overmolding process.

(8) Lithium molybdate Li.sub.2MoO.sub.4 may be used as a raw material to prepare the ceramic heat insulation. The raw material may be argillaceous (clayish) material, paste, slurry, or a less viscous fluid that enables forming or molding of the material according to an embodiment.

(9) An exemplary process for thermally insulating the electronic component with the ceramic thermal insulation material containing lithium molybdate, may include pressure molding (i.e. press molding), molding (i.e. slip casting), dipping, or 3D printing (three-dimensional printing).

(10) The process for the manufacture of an electronic component that is thermally insulated with the ceramic thermal insulation material containing lithium molybdate, may include pressure molding (press molding), molding (slip casting), dipping, or 3D printing (three-dimensional printing).

(11) In pressure molding, the electronic component(s) is (are) placed in a mold (die), and the mold is filled with the ceramic thermal insulation material which may be lithium molybdate in clayish form, to cover the component(s). The mold is subjected to compression, wherein most of the water present in the ceramic is removed. The molded product, i.e. the ceramic-covered electronic component is dried to remove the rest of the water. The drying may be carried out in room temperature, or the drying may be carried out at an elevated temperature to enhance the drying. The drying temperature may be 20° C. or above, preferably 50° C. to 120° C. In pressure molding, a rigid ceramic thermal insulation layer is obtainable, enabling a feasible physical strength of the component.

(12) In 3D printing, the ceramic thermal insulation material may be printed on the electronic component by using a 3D printer that is capable of 3D printing of paste-like material. Ceramic thermal insulation material is applied on the electronic component(s) layer by layer until a desired shape of the product is obtained and/or the electronic component is completely covered by the ceramic to obtain sufficient thermal insulation of the electronic component. In 3D printing, the electronic component need not be subjected to pressure. Thus, the damage possibly caused by the pressure to the electronic component is avoided in 3D printing. Also the need to prepare the mold is avoided.

(13) In molding (slip casting), the electronic component(s) is (are) placed in the mold (die), and the mold is filled with the ceramic thermal insulation material to cover the component(s). However, mild pressure conditions are applied during molding.

(14) The ceramic structure obtainable by molding or 3D printing is weaker if compared to the ceramic structure obtainable by pressure molding. However, the weaker structure of the ceramic obtainable by molding or 3D printing may mean that the ceramic layer is more porous and thus provides better thermal insulation of the electronic component.

(15) The electronic component may be partly or completely covered by the ceramic thermal insulation material, wherein the layer of the ceramic thermal insulation material on top of the component is thick enough to obtain sufficient thermal insulation of the electronic component, for example, to withstand overmolding. For example, a thickness the ceramic thermal insulation material layer covering the component may be 0.5 mm to 10 mm.

(16) An embodiment provides a ceramic thermal insulation that may be directly applied on the electronic component. In addition to thermal protection of electronic or electric components, the ceramic thermal insulation material and process may also be utilised for thermal insulation of any other smaller objects in any field of technology, such as high temperature sensors, motor drives, etc.

(17) In an embodiment, the electronic component is completely thermally protected, such that each part of the electronic component is thermally protected by the ceramic thermal insulation.

(18) In an embodiment, the electronic component is only partly thermally protected; for example, a part (parts) of the electronic component that is (are) not heat sensitive, need not be thermally protected by the ceramic thermal insulation.

(19) Examples of electronic components that may be thermally protected by the ceramic thermal insulation include batteries, supercapacitors, electrolytic capacitors, light emitting diodes (LED), active components, sensors, integrated circuits (IC), electrical interconnections. For example, the electronic component may comprise a battery and at least two electrical interconnections.

(20) Thus the heat resistant electronic component may be an integrated entity formed by the electronic component covered by the ceramic thermal insulation.

(21) Thus an embodiment discloses a heat resistant electronic component comprising an electronic component covered by a layer of ceramic thermal insulation material containing lithium molybdate Li.sub.2MoO.sub.4. The electronic component may comprise at least one of a battery, an electrical connection path, and conditioning electronics. The layer of ceramic thermal insulation material may contain at least one additive material to modify the heat conduction properties.

(22) An embodiment discloses a process for manufacturing a heat resistant electronic component, comprising obtaining ceramic thermal insulation material containing lithium molybdate Li.sub.2MoO.sub.4, in a mouldable form; optionally mixing the ceramic thermal insulation material with at least one additive; covering an electronic component with the material; shaping the material covering the electronic component into a desired form; and drying the desired form at a temperature of from 20° C. to 120° C. The process may comprise at least one of 3D printing of the material on top of the electronic component, molding of the material on top of the electronic component, and pressure molding of the material on top of the electronic component.

(23) An embodiment discloses the use of lithium molybdate Li.sub.2MoO.sub.4 for thermal insulation of an electronic component.

(24) An embodiment discloses the use of lithium molybdate Li.sub.2MoO.sub.4 for the manufacture of a heat resistant electronic component.

(25) An embodiment discloses an electronic product comprising said heat resistant electronic component.

(26) FIG. 1 illustrates exemplary heat resistant electronic components comprising an electronic component covered by a layer of ceramic thermal insulation material 1 (such as Li.sub.2MoO.sub.4). The heat resistant electronic component further comprises the electronic component 3, and at least one an electrical connection 4. The heat resistant electronic component may further comprise filler material(s) 2 (such as glass beads), an electrical connection 5 with or without electrical insulation, and/or a molded/cast case 6 (e.g, of polymer/metal).

(27) The process may be performed at a temperature of from 20° C. to 150° C.

(28) The temperature in the process for manufacturing the component does not exceed 150° C., nor does it need to exceed the boiling temperature of the solvent. No extra heating is required in the process, instead the compression may be performed at a room temperature. Optional heat treatment may be performed after the shaping and compacting of the component. The process time to prepare the component may be only 2 to 5 min.

(29) No forming of a mixture on two or more substrates and laminating the two or more substrates with a sintered inorganic compound or composite is required in the process.

(30) The process and the component are provided to enhance thermal protection of the component. No compressing is required in the process, and elevated temperature of about 20-120° C. may be used for the drying only. Optionally 3D printing, molding, or pressure molding may be utilized in the process, none of which require elevated temperature. Pressure molding is not mandatory in the process.

(31) The process may be utilized in thermal protection of an electronic product, as the components to be protected are not destroyed during the manufacture process.

(32) The process may be performed at an atmospheric pressure.

(33) No sintering of ceramic at extremely high temperatures (e.g. 1500° C.) is required in the process. No removal of organic additives by firing at high temperatures (e.g. 700° C.) is required in the process.

(34) It will be obvious to a person skilled in the art that, as the technology advances, the inventive concept can be implemented in various ways. The invention and its embodiments are not limited to the examples described above but may vary within the scope of the claims.