Large lithium battery heat insulation calorimeter with weighing device

Abstract

The utility model discloses a large lithium battery heat insulation calorimeter with a weighing device. The lithium battery thermal insulation calorimeter comprises a thermal insulation calorimeter main body and a weighing sensor fixed above the thermal insulation calorimeter main body, wherein the weighing sensor is used for acquiring the mass of a lithium battery for thermal insulation test in the thermal insulation calorimeter main body. According to the utility model, the real-time mass change of the lithium battery is measured through the weighing sensor, and the research on the mass change rule of the lithium battery under the adiabatic thermal runaway condition is realized.

Description

Technical Field

[0001] The utility model relates to the technical field of battery safety testing, in particular to a lithium battery adiabatic calorimeter with a weighing device. Background Art

[0002] An adiabatic accelerating calorimeter provides an approximately adiabatic environment by precisely tracking the temperature to avoid heat exchange between the sample under test and the environment, and mainly tests and analyzes the exothermic behavior of the sample under test. A battery adiabatic calorimeter can simulate the thermal characteristics of the exothermic reaction process when the heat inside the battery cannot be dissipated in time, simulate the thermal runaway process caused by external factors, and obtain the apparent exothermic law of the battery under thermal runaway conditions.

[0003] In the existing battery adiabatic testing technology, a lithium-ion battery is fixed in an adiabatic calorimeter, and a temperature-measuring thermocouple is fixed on the surface of the battery to obtain the temperature change of the battery during the thermal runaway process. Then, to obtain the amount of heat released by the battery, it is necessary to clarify an important parameter, the specific heat capacity of the battery. However, within a certain temperature range, the average specific heat capacity of the battery is closely related to its mass. When the battery undergoes self-exothermic reaction, its mass will change. If the specific heat capacity under a fixed mass is used, the value of the heat released by the battery will be inaccurate, and it is impossible to accurately evaluate the magnitude of the battery's runaway power. The existing calorimeters cannot measure the mass change of a lithium battery during the exothermic process. Summary of the Utility Model

[0004] In order to solve the above technical problems, the utility model provides a lithium battery adiabatic calorimeter with a weighing device, which can obtain the heat released by the battery by accurately measuring the mass change of the lithium battery during the exothermic process.

[0005] The technical solution for achieving the purpose of the utility model is as follows:

[0006] The utility model includes an adiabatic calorimeter main body and a weighing sensor fixed above the adiabatic calorimeter main body. The weighing sensor is used to obtain the mass of the lithium battery undergoing adiabatic testing inside the adiabatic calorimeter main body.

[0007] Furthermore, the weighing sensor is fixed on a load-bearing bottom plate through a bracket, and the load-bearing bottom plate is fixed on an adapter plate.

[0008] Furthermore, the weighing sensor adopts a digital weighing sensor, and a hook for hanging a lithium-ion battery is provided on the digital weighing sensor.

[0009] Furthermore, the hook is connected to the lithium battery inside the adiabatic calorimeter main body through a nylon rope.

[0010] Furthermore, the adapter plate and the load-bearing plate are both provided with openings, and directly above the openings is the hook.

[0011] An important component of the present utility model is a digital load cell, which integrates analog-to-digital conversion and communication and does not require an external converter. It saves space in the equipment and control cabinet and reduces the system complexity. There are screw holes under the load cell for fixing a hook, and the hook is used to hang a lithium battery. The load cell measures gravity based on the piezoelectric effect. The change in the mass of the lithium battery will cause a change in the deformation of the load cell, and at the same time, the piezoelectric crystal of the load cell will generate charges, thus generating a voltage signal. The voltage signal is converted into a digital signal by a digital converter, so that the output of the load cell is the mass of the battery. During the weighing process, operations such as zero calibration and magnification calibration are performed to ensure the accuracy and reliability of the output mass value. The computer terminal records the battery mass value in real time. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a schematic structural diagram of the weighing device according to an embodiment of the present application;

[0013] Figure 2 is a schematic diagram of a calorimeter according to an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0014] Now, the present utility model patent will be further described in detail with reference to the drawings and embodiments. These drawings are all simplified schematic diagrams, which only illustrate the basic structure of the present utility model in a schematic manner, so they only show the components related to the present utility model.

[0015] As Figure 1 shown, an embodiment of the present application provides a weighing device for adiabatic testing of large lithium batteries. The bottom is an adapter plate 2, which is installed on a large battery adiabatic calorimeter accelerating calorimeter. Above the adapter plate is a load-bearing bottom plate 3, and a bracket 4 is installed on the load-bearing bottom plate. The bracket is used to fix a digital load cell 5.

[0016] Furthermore, the digital load cell records the change in the mass of the battery during the test through the change in deformation. In a certain embodiment, its model is selected as SLP331D.

[0017] Figure 2 Shown is a large battery adiabatic accelerating calorimeter 1, whose model is ARC Titans 1000, and the above-mentioned weighing device 6 is configured on its upper part. In order to adapt to the large battery adiabatic accelerating calorimeter 1, the opening of the adapter plate 2 is installed facing the opening of the top cover plate of the adiabatic accelerating calorimeter, the opening of the load-bearing plate 3 is installed facing the opening of the adapter plate 2, and the bracket 4 is installed at a position slightly behind and above the load-bearing plate 3 so that the position where the digital load cell 5 hangs the lithium battery is exactly at the opening of the adapter plate 2.

[0018] In one embodiment, a lithium battery is tied to the front end of the digital load cell 5 with a nylon rope, directly opposite the opening of the adapter plate 2, and then the battery is subjected to an adiabatic heating test in an adiabatic calorimeter.

[0019] The working process of the present utility model:

[0020] Start the test software of the battery adiabatic accelerating calorimeter, set parameters such as the starting temperature, heating step, waiting time, and termination temperature, and start the battery adiabatic test.

[0021] The large-scale battery adiabatic calorimeter performs heating-waiting-searching tests according to the set parameters, and records the temperature and mass changes of the battery in real time.

[0022] The data transmitted by the thermocouple is used to plot the curve of the battery's temperature and time, obtaining the time from self-heating to thermal runaway. The data transmitted by the digital load cell can be used to obtain the mass change of the lithium battery, and thus obtain an important parameter of the battery specific heat capacity.

[0023] The technical means disclosed in the solution of the present utility model are not limited to the technical means disclosed by the above technical means, but also include technical solutions composed of equivalent replacements of the above technical features. Matters not covered by the present utility model belong to the common general knowledge of those skilled in the art.

Claims

1. A large-scale lithium battery adiabatic calorimeter with a weighing device, characterized in that It includes an adiabatic calorimeter main body and a weighing sensor fixed above the adiabatic calorimeter main body, and the weighing sensor is used to obtain the mass of the lithium battery for adiabatic testing inside the adiabatic calorimeter main body.

2. The large lithium battery adiabatic calorimeter with a weighing device according to claim 1, characterized in that The weighing sensor is fixed on the load-bearing bottom plate through a bracket, and the load-bearing bottom plate is fixed on the adapter plate.

3. A large lithium battery adiabatic calorimeter with a weighing device according to claim 2, characterized in that, The weighing sensor adopted is a digital weighing sensor, and a hook for hanging the lithium-ion battery is provided on the digital weighing sensor.

4. A large lithium battery adiabatic calorimeter with a weighing device according to claim 3, characterized in that, The hook is connected to the lithium battery inside the adiabatic calorimeter main body through a nylon rope.

5. A large lithium battery adiabatic calorimeter with a weighing device according to claim 3, characterized in that, Both the adapter plate and the load-bearing bottom plate have openings, and directly above the openings is the hook.

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