High precision isothermal calorimeter

Abstract

The utility model provides a kind of high-precision isothermal calorimeter, including rack, cooling plate, isothermal plate, heater, pressurizing system, vacuum insulation system and measurement and control system, a pair of isothermal plate oppositely set and form test space for placing sample to be tested between each other, a pair of isothermal plate sets cooling plate in the side away from sample to be tested, rack is formed with closed and the vacuum pump communication of vacuum insulation system's working cavity, pressurizing system can drive cooling plate to drive corresponding isothermal plate each other to pressurize sample to be tested, isothermal plate, cooling plate and sample to be tested are set in the working cavity, measurement and control system includes temperature detector for collecting isothermal plate temperature information, heater is used to heat isothermal plate.According to the utility model, cooling plate can be controlled to drive heat insulation plate to pressurize solid-state battery, and the heat production test work of solid-state battery charge-discharge is successfully completed.

Description

Technical Field

[0001] This utility model relates to the field of battery testing technology, and in particular to a high-precision isothermal calorimeter. Background Technology

[0002] Isothermal calorimeters are suitable for testing the heat release / endothermic properties of batteries during charge and discharge. The testing principle involves maintaining a constant temperature in the working chamber and on the test sample, ensuring the sample is in an isothermal state. When the sample generates heat, the heating power is adjusted in real-time to maintain a constant sample temperature, thereby obtaining the heat generation / endothermic power of the sample and measuring the heat absorbed or released under that temperature condition. Due to the interface characteristics of solid-state batteries, pressurization is required during charge and discharge. Currently, there is no technology that integrates pressurization testing and isothermal calorimetry for solid-state batteries. Utility Model Content

[0003] This invention provides a high-precision isothermal calorimeter.

[0004] Specifically, this utility model is achieved through the following technical solution:

[0005] This utility model provides a high-precision isothermal calorimeter, characterized by comprising a frame, a cooling plate, a heat spreader, a heater, a pressurization system, a vacuum insulation system, and a measurement and control system. A pair of heat spreaders are arranged opposite each other, forming a test space for placing the test sample. A cooling plate is arranged on the side of the pair of heat spreaders away from the test sample. The frame forms a closed working chamber that is connected to a vacuum pump of the vacuum insulation system. The pressurization system can drive the cooling plate to bring the corresponding heat spreaders closer together to apply pressure to the test sample. The heat spreader, the cooling plate, and the test sample are arranged in the working chamber. The measurement and control system includes a thermometer for collecting the temperature information of the heat spreader, and a heater for heating the heat spreader.

[0006] In some embodiments, a thermally conductive film is also included, which is disposed on the heat spreader near the sample to be tested.

[0007] In some embodiments, the measurement and control system further includes a rangefinder, which is used to collect expansion displacement information of the sample to be measured.

[0008] In some embodiments, the pressurization system includes a piston mechanism and a pressure plate, wherein the piston rod of the piston mechanism is connected to the pressure plate, and the pressure plate abuts against a cooling plate.

[0009] In some embodiments, a pressure sensor is disposed on the pressure plate near the test sample.

[0010] In some embodiments, a cooling channel is formed inside the cooling plate, and the cooling channel is connected to a cooling temperature control device. In some embodiments, another pair of heat-spreading plates, different from the pair of heat-spreading plates, are arranged opposite each other and form a control space between them for placing a control sample. The other pair of heat-spreading plates has a cooling plate on the side away from the control sample. The cooling plate can drive the corresponding heat-spreading plates to move closer to each other, thereby simultaneously applying pressure to the test sample and the control sample. The control sample is placed in the working chamber. The system also includes a charge / discharge device, which is electrically connected to the test sample.

[0011] In some embodiments, the pressurization system includes a pressure plate, a base plate, and a guide post. The pressure plate and the base plate are respectively disposed on the side of a pair of cooling plates away from the test sample. One end of the guide post is fixedly connected to one of the pressure plate and the base plate, and the other end of the guide post is guidedly connected to the other of the pressure plate and the base plate.

[0012] In some embodiments, the rangefinder is selected from laser displacement sensors or capacitive micro-displacement sensors.

[0013] According to an embodiment of this utility model, by connecting a pressurization system to a cooling plate, the cooling plate can be controlled to apply pressure to the solid-state battery via an insulating plate during the heat generation / absorption test of the solid-state battery under charge / discharge conditions, thus successfully completing the heat generation / absorption test of the solid-state battery during charge / discharge. Simultaneously, since the heat generation / absorption measurement accuracy requirements during the charge / discharge process of solid-state batteries are high, a vacuum pump is connected to the closed working chamber to provide a vacuum testing environment for the solid-state battery. This avoids the problem of decreased temperature measurement accuracy caused by heat leakage from the calorimeter body and the high thermal conductivity of the material, thereby meeting the accuracy requirements for the heat generation / absorption test of the solid-state battery during charge / discharge.

[0014] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0015] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0016] Figure 1 This is a schematic diagram of a high-precision isothermal calorimeter according to one embodiment of the present invention;

[0017] Figure 2 This is a schematic diagram of a high-precision isothermal calorimeter according to another embodiment of the present invention.

[0018] Figure label:

[0019] 01: Solid-state battery under test; 02: Control solid-state battery; 1: Frame; 2: Working chamber; 3: Heat spreader; 4: Cooling plate; 6: Guide post; 7: Piston mechanism; 8: Charger / discharger; 9: Coolant temperature control device; 10: Control box; 11: Host computer; 12: Heater; 13: Pressure plate; 14: Base plate. Detailed Implementation

[0020] The present invention will now be discussed with reference to several embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and thus implement the present invention, and are not intended to imply any limitation on the scope of the present invention.

[0021] As used herein, the term "comprising" and its variations are to be interpreted as open-ended terms meaning "including but not limited to"; the terms "embodiment" and "one embodiment" are to be interpreted as "at least one embodiment"; the term "another embodiment" is to be interpreted as "at least one other embodiment"; the terms "first," "second," etc., may refer to different or the same objects; the term "setup" is not limited to direct or indirect connections, nor to specific connection methods. Other explicit and implicit definitions may also be included below.

[0022] Specific numerical values ​​or ranges may be mentioned in the following description. It should be understood that these values ​​and ranges are merely exemplary and may be helpful in putting the ideas of this invention into practice. However, the description of these examples is not intended to limit the scope of this invention in any way. These values ​​or ranges may be set differently depending on the specific application scenario and requirements.

[0023] As mentioned above, existing technologies do not yet provide a combined pressure testing and isothermal calorimetry technique for solid-state batteries. The high-precision isothermal calorimeter proposed in the embodiments of this invention at least partially solves the above-mentioned problems. The following will refer to... Figure 1 and Figure 2 This describes the structure and working principle of the high-precision isothermal calorimeter according to this utility model. For example... Figure 1 and Figure 2As shown, the high-precision isothermal calorimeter of this embodiment generally includes a frame 1, a heat spreader 3, a cooling plate 4, a thermally conductive film, a heater 12, a pressurization system, a vacuum insulation system, a measurement and control system, a coolant temperature control device 9, a control box 10, a charge / discharger 8, and a host computer 11. The heat spreader 3 is used to achieve uniform temperature transfer between the heat spreader 3 and the solid-state battery. The cooling plate 4 is used to cool the heat spreader 3 to maintain a constant temperature. The thermally conductive film is used to improve the temperature transfer efficiency between the heat spreader 3 and the solid-state battery. The heater 12 heats the heat spreader 3 to increase its temperature. The pressurization system is used to control the heat spreader 3 to pressurize the solid-state battery. The charge / discharger 8 is used to charge and discharge the solid-state battery. The measurement and control system is used to collect information and control the power of the heater 12. The coolant temperature control device 9 circulates coolant to the cooling plate 4. The control box 10 is used to control the operation of the measurement and control system. The host computer 11 is connected to the control box 10 for operation.

[0024] It should be noted that the high-precision isothermal calorimeter of this utility model is applicable to test samples that are not limited to solid-state batteries. In order to clearly describe the high-precision isothermal calorimeter of this utility model, the following description will only take solid-state batteries as an example.

[0025] The frame 1 of the high-precision isothermal calorimeter of this embodiment is used to support the main functional components of the calorimeter. However, according to the concept of this embodiment, the frame 1 also forms at least a closed working chamber 2. A vacuum pump of a vacuum insulation system is connected to the wall of the working chamber 2. During the test, the vacuum pump can create a vacuum environment inside the working chamber 2. The heat generated by the solid-state battery, heater 12, and other components is efficiently insulated using the vacuum insulation principle, avoiding the problem of decreased temperature measurement accuracy caused by heat leakage from the calorimeter body and the high thermal conductivity of the materials, thereby meeting the accuracy requirements for heat generation testing of solid-state battery charging and discharging. The vacuum insulation system also includes functional components for controlling the start and stop of the vacuum pump, its speed, and monitoring the vacuum level inside the working chamber 2. The solid-state battery under test 01, the control solid-state battery 02, the cooling plate 4, the heat spreader 3, and other components are all placed inside the vacuum working chamber 2.

[0026] The working chamber 2 contains a sandwich-structured temperature transfer composite layer. The core of the sandwich structure holds the solid-state battery under test (01) and a control solid-state battery (02). From the core outwards, there are sequentially arranged a thermally conductive film, a heat spreader 3, and a cooling plate 4, all arranged in pairs. In one embodiment, only one pair of thermally conductive film, heat spreader 3, and cooling plate 4 is used to test the solid-state battery under test (01). In another embodiment, two pairs of thermally conductive film, heat spreader 3, and cooling plate 4 are used to test the solid-state battery under test (01) and the control solid-state battery (02) respectively, thereby achieving differential testing.

[0027] The pressurization system includes a piston mechanism 7, a pressure plate 13, a base plate 14, and a guide post 6. The base plate 14 is located at the bottom of the working chamber 2 and supports the bottom of the cooling plate 4 below, thereby providing stable support for the heat-conducting film, the heat-spreading plate 3, and the cooling plate 4 below. The pressure plate 13 is located on top of the cooling plate 4 above. The pressure plate 13 can be integrated with the cooling plate 4, allowing it to move up and down together with the heat-conducting film, the heat-spreading plate 3, and the cooling plate 4. Alternatively, the pressure plate 13 can be separated from the cooling plate 4. When the pressure plate 13 descends and abuts against the cooling plate 4 above, it can push the cooling plate 4, along with the heat-conducting film and the heat-spreading plate 3, to descend together. The piston rod of the piston mechanism 7 is connected to the pressure plate 13, controlling the extension of the piston rod to pressurize the solid-state battery 01 under test and the control solid-state battery 02 using a pair of heat-spreading plates 3. For example, the piston mechanism can be a cylinder or a hydraulic cylinder.

[0028] The coolant channels formed inside the cooling plate 4 are connected to the coolant temperature control device 9. For example, the coolant can be cooling water or cooling oil.

[0029] The measurement and control system includes a temperature sensor, a distance sensor, and a pressure sensor. The temperature sensor is used to collect the temperature of the heat spreader 3. For example, the temperature sensor can be placed on the surface of the heat spreader 3 or inside the heat spreader 3. The distance sensor is used to collect the expansion displacement information of the solid-state battery. For example, the distance sensor can be a laser displacement sensor or a capacitive micro-displacement sensor. The pressure sensor is used to collect the pressure values ​​applied by the pressurization system to the solid-state battery under test 01 and the reference solid-state battery 02. For example, the pressure sensor can be placed on the surface of the pressure plate near the solid-state battery side.

[0030] The heater 12 can be disposed between the cooling plate 4 and the heat spreader 3 and attached to the surface of the heat spreader 3, thereby efficiently heating the heat spreader 3. For example, the heater 12 can be attached to the surface of the heat spreader 3.

[0031] Using the high-precision isothermal calorimeter of this utility model embodiment can avoid problems such as inaccurate test accuracy and slow response caused by heat leakage and material heat absorption. It adopts a matched control solid-state battery 02 to realize differential method to synchronously eliminate test deviations, and can realize solid-state battery pressurization state test and real-time expansion test functions.

[0032] The description of the embodiments herein, including any references to directions and orientations, is for ease of description only and should not be construed as limiting the scope of protection of this utility model. The description of preferred embodiments involves combinations of features, which may exist independently or in combination; this utility model is not particularly limited to the preferred embodiments. The scope of this utility model is defined by the claims.

[0033] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A high-precision isothermal calorimeter, characterized in that, The system includes a frame, cooling plates, heat spreaders, heaters, a pressurization system, a vacuum insulation system, and a measurement and control system. A pair of heat spreaders are arranged opposite each other, forming a test space for placing the test sample. A cooling plate is arranged on the side of the heat spreaders away from the test sample. The frame forms a closed working chamber that is connected to the vacuum pump of the vacuum insulation system. The pressurization system can drive the cooling plates to bring the corresponding heat spreaders closer together to apply pressure to the test sample. The heat spreaders, cooling plates, and test sample are arranged in the working chamber. The measurement and control system includes a thermometer for collecting temperature information of the heat spreaders, and a heater for heating the heat spreaders.

2. The high-precision isothermal calorimeter according to claim 1, characterized in that, It also includes a thermally conductive film, which is placed on the heat spreader near the sample to be tested.

3. The high-precision isothermal calorimeter according to claim 1, characterized in that, The measurement and control system also includes a rangefinder, which is used to collect the expansion displacement information of the sample under test.

4. The high-precision isothermal calorimeter according to claim 1, characterized in that, The pressurization system includes a piston mechanism and a pressure plate. The piston rod of the piston mechanism is connected to the pressure plate, and the pressure plate abuts against the cooling plate.

5. The high-precision isothermal calorimeter according to claim 4, characterized in that, A pressure sensor is installed on the side of the pressure plate closest to the sample to be tested.

6. The high-precision isothermal calorimeter according to claim 1, characterized in that, The cooling plate has coolant channels inside, which are connected to the coolant temperature control device.

7. The high-precision isothermal calorimeter according to claim 1, characterized in that, Unlike the pair of heat-spreading plates mentioned above, another pair of heat-spreading plates are arranged opposite each other and form a control space for placing a control sample. The other pair of heat-spreading plates are provided with a cooling plate on the side away from the control sample. The cooling plate can drive the corresponding heat-spreading plates to move closer to each other, thereby simultaneously applying pressure to the test sample and the control sample. The control sample is placed in the working chamber. It also includes a charge / discharge device, which is electrically connected to the test sample.

8. The high-precision isothermal calorimeter according to claim 1, characterized in that, The pressurization system includes a pressure plate, a base plate, and a guide post. The pressure plate and the base plate are respectively located on the side of a pair of cooling plates away from the test sample. One end of the guide post is fixedly connected to one of the pressure plate and the base plate, and the other end of the guide post is guidedly connected to the other of the pressure plate and the base plate.

9. The high-precision isothermal calorimeter according to claim 3, characterized in that, The rangefinder uses either a laser displacement sensor or a capacitive micro-displacement sensor.

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