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CN-122016925-A - Heat conduction coefficient measuring method and device for heat insulation material

CN122016925ACN 122016925 ACN122016925 ACN 122016925ACN-122016925-A

Abstract

The invention relates to the technical field of batteries, and particularly discloses a method and a device for measuring heat conductivity coefficient of a heat insulation material. The method comprises the steps of placing a heating plate between a first heat sink plate and a second heat sink plate which are oppositely arranged, respectively placing a material sheet to be tested and an incompressible contrast material sheet with known heat conductivity on two sides of the heating plate, applying pressure to enable all parts to be closely attached, measuring the thickness of the material sheet to be tested, heating through the heating plate, respectively collecting the temperature of one side, far away from the material sheet to be tested, of the heating plate, between the heating plate and the material sheet to be tested, between the material sheet to be tested and the first heat sink plate, between the heating plate and the contrast material sheet, between the contrast material sheet and the second heat sink plate, and on one side, far away from the contrast material sheet, of the second heat sink plate, collecting the ambient temperature, and calculating the heat conductivity of the material sheet to be tested according to a formula. According to the invention, the heat conductivity coefficient can be rapidly calculated by a double-path comparison measurement mode without waiting for steady-state heat transfer, and the test period is greatly shortened.

Inventors

  • YANG JUANJUAN

Assignees

  • 上海国轩新能源有限公司

Dates

Publication Date
20260512
Application Date
20260330

Claims (10)

  1. 1. The method for measuring the heat conductivity coefficient of the heat insulation material is characterized by comprising the following steps of: Placing a heating plate between the heat sink plate I and the heat sink plate II which are oppositely arranged, and then respectively placing a material sheet to be tested and a comparison material sheet at two sides of the heating plate, applying pressure to tightly adhere all the components and measuring the thickness delta 2 of the material sheet to be tested, wherein the comparison material sheet is incompressible and has a known heat conductivity coefficient lambda 1 ; Heating a material sheet to be detected and a contrast material sheet through the heating plate, collecting the temperature T 11 between the heating plate and the contrast material sheet, the temperature T 12 between the contrast material sheet and the second heat sink plate and the temperature T 13 on one side of the second heat sink plate far away from the contrast material sheet, collecting the temperature T 21 between the heating plate and the material sheet to be detected, the temperature T 22 between the material sheet to be detected and the second heat sink plate and the temperature T 23 on one side of the first heat sink plate far away from the material sheet to be detected, and collecting the environmental temperature T amb ; the thermal conductivity lambda x of the sheet of material to be measured is calculated according to the following formula: where δ 1 is the thickness of the contrast material sheet.
  2. 2. The method for measuring thermal conductivity of heat insulating material according to claim 1, wherein the first heat sink plate and the second heat sink plate are the same in size and material, and both sides of the first heat sink plate and the second heat sink plate are smooth and flat.
  3. 3. The method for measuring the thermal conductivity of the heat insulating material according to claim 2, wherein the size of the material sheet to be measured and the size of the contrast material sheet are the same, and the contrast material sheet is an aluminum sheet, a stainless steel sheet, a mica sheet or a nano sheet.
  4. 4. The method for measuring the thermal conductivity of a heat insulating material according to claim 2, wherein the sheet of material to be measured, the sheet of contrast material, the first heat sink plate and the second heat sink plate are square structures with the same size, the sheet of material to be measured is completely attached to the first heat sink plate, and the sheet of contrast material is completely attached to the second heat sink plate.
  5. 5. The method for measuring the thermal conductivity of a thermal insulation material according to claim 1, wherein the sheet of material to be measured and the sheet of contrast material are kept in a vertical state during the heating process.
  6. 6. A heat-insulating material heat conductivity coefficient measuring device is characterized by comprising a support, a heating plate, a first heat sink plate, a second heat sink plate, an adjusting piece, a temperature collecting piece, a material piece to be measured and a comparison material piece which is of known heat conductivity coefficient and incompressible, wherein the first heat sink plate is arranged on the support through the adjusting piece, the second heat sink plate and the first heat sink plate are oppositely arranged and fixed on the support, the heating plate is arranged between the first heat sink plate and the second heat sink plate, the material piece to be measured is arranged between the heating plate and the first heat sink plate, the comparison material piece is arranged between the heating plate and the second heat sink plate, the heat sink plate is driven to move towards the second heat sink plate through the adjusting piece so as to enable all parts to be closely attached, and the temperature collecting piece is used for collecting the temperature T 11 between the heating plate and the comparison material piece, the temperature T 12 between the comparison material piece and the second heat sink plate, the temperature T 13 on one side of the heat sink plate away from the comparison material piece, the temperature T 21 between the heating plate and the material piece to be measured, the temperature 22 between the material piece to be measured and the first heat sink plate, the temperature T 23 on one side of the material piece away from the material piece to be measured, and the temperature T amb .
  7. 7. The heat insulation material heat conductivity measuring device according to claim 6, wherein the first heat sink plate and the second heat sink plate are vertically and oppositely arranged, the adjusting piece comprises a screw rod and a connecting plate, the screw rod is horizontally arranged and is in threaded fit connection with the support, one end of the screw rod is in rotary fit connection with the connecting plate, the other end of the screw rod is connected with the rotating wheel, a plurality of horizontally arranged mounting rods are arranged on the connecting plate, the first heat sink plate is fixed on the plurality of mounting rods, the length of the mounting rods is not smaller than the height of the first heat sink plate, and the second heat sink plate is mounted on the support through a plurality of horizontally arranged fixing rods, and the length of the fixing rods is not smaller than the height of the second heat sink plate.
  8. 8. The heat insulation material heat conductivity measuring device according to claim 6, wherein the temperature collecting piece comprises a first thermocouple, a second thermocouple, a third thermocouple, a fourth thermocouple, a fifth thermocouple and a sixth thermocouple, wherein the first and second sides of the first and second heat sink plates are respectively provided with a first mounting groove and a second mounting groove, the first and second thermocouples are respectively arranged in the first and second mounting grooves, the first and second sides of the first and second heat sink plates, which are far away from each other, are respectively provided with a third and fourth mounting groove, the third and fourth thermocouples are respectively arranged in the third and fourth mounting grooves, the side of the heating plate facing the first heat sink plate is provided with a fifth mounting groove and the fifth thermocouple is arranged in the third mounting groove, the side of the heating plate facing the second heat sink plate is provided with a sixth mounting groove and the sixth thermocouple is arranged in the fourth mounting groove.
  9. 9. The device for measuring the thermal conductivity of a heat insulating material according to claim 6, wherein the heating plate comprises an aluminum plate and a heating pipe embedded in the aluminum plate, the aluminum plate has a square structure, and two side surfaces of the aluminum plate are smooth and flat.
  10. 10. The heat-insulating material heat conductivity measuring device according to claim 6, wherein the first heat sink plate, the second heat sink plate, the material sheet to be measured and the contrast material sheet are square structures with the same size, the two opposite sides of the first heat sink plate and the two opposite sides of the first heat sink plate are smooth and flat, the material sheet to be measured is completely attached to the first heat sink plate, the contrast material sheet is completely attached to the second heat sink plate, and the contrast material sheet is an aluminum sheet, a stainless steel sheet, a mica sheet or a nano sheet.

Description

Heat conduction coefficient measuring method and device for heat insulation material Technical Field The invention relates to the technical field of batteries, in particular to a method and a device for measuring heat conductivity coefficient of a heat insulation material. Background In the design and development of new energy battery packs, the suppression of thermal runaway spread is one of the core safety indexes. In order to prevent the single battery from spreading to adjacent batteries or modules after thermal runaway, efficient heat insulation materials are arranged among batteries, between modules and between the modules and the box body. The thermal conductivity of the thermal insulation material directly determines the thermal insulation performance, so in practical engineering, a material with a lower thermal conductivity is generally preferred. At present, the test of the heat conductivity coefficient mainly depends on a heat conductivity coefficient tester based on a steady state method principle, and the heat conductivity coefficient of the material is obtained by measuring the temperature difference or heat flow of the front surface and the rear surface of the heat conducting material based on the heat conductivity law of Fourier. In order to ensure the accuracy and reliability of the measured value, heat preservation and heat protection treatment needs to be carried out on the test materials of the test system in other directions except for the heat conduction direction, so that the mass heat capacity of the test system is larger, the time constant of the test system is increased, the time for reaching a steady state is longer, the test time is prolonged, and the time for the test system to reach the steady state is about three hours. In practical engineering, commonly used heat insulation materials include aerogel, silicon foam, nano-plate, etc., wherein aerogel and silicon foam are widely used due to their compressible properties. However, such compressible materials are often inevitably compressed during the grouping of the battery modules or the battery packs due to factors such as assembly tolerances, structural constraints, and processes. Research shows that the heat conductivity coefficients of materials before and after compression have obvious difference, so that a series of problems occur in practical engineering, such as a contrary result of actual heat insulation effect when the nominal values of the heat conductivity coefficients of different materials are similar, whether the heat conductivity coefficients of materials provided by suppliers are consistent with the nominal values of specifications of products of the materials is difficult to verify, and the change rule of the heat conductivity coefficients of compressible materials under any compression multiplying power is not clear, so that a quick and effective test means is lacked. Disclosure of Invention Based on the above, the invention aims to provide a method and a device for measuring the heat conductivity coefficient of a heat insulating material, which simplify the structure of a test system, do not need to set heat protection for the test system, enable the test system to reach a steady state for about half an hour, improve the test efficiency and quickly measure the heat conductivity coefficients of various incompressible materials and the heat conductivity coefficients of compressible materials under different compression ratios. In order to achieve the above purpose, the present invention adopts the following technical scheme: The invention provides a heat conduction coefficient measuring method of a heat insulation material, which comprises the following steps: Placing a heating plate between the heat sink plate I and the heat sink plate II which are oppositely arranged, and then respectively placing a material sheet to be tested and a comparison material sheet at two sides of the heating plate, applying pressure to tightly adhere all the components and measuring the thickness delta 2 of the material sheet to be tested, wherein the comparison material sheet is incompressible and has a known heat conductivity coefficient lambda 1; Heating a material sheet to be detected and a contrast material sheet through the heating plate, collecting the temperature T 11 between the heating plate and the contrast material sheet, the temperature T 12 between the contrast material sheet and the second heat sink plate and the temperature T 13 on one side of the second heat sink plate far away from the contrast material sheet, collecting the temperature T 21 between the heating plate and the material sheet to be detected, the temperature T 22 between the material sheet to be detected and the second heat sink plate and the temperature T 23 on one side of the first heat sink plate far away from the material sheet to be detected, and collecting the environmental temperature T amb; the thermal conductivity lambda x of the sheet of mate