Accelerating Rate Calorimeter

ARC-D50s

I. Equipment Purpose

By virtue of precise temperature tracking, this equipment prevents heat exchange between the tested sample and the environment, thereby creating an approximately adiabatic environment. It is mainly used to test and analyze the exothermic behavior of the tested samples. Utilizing the accelerating rate calorimeter (ARC), it can simulate the thermal characteristics of exothermic reactions when heat inside the battery fails to dissipate in a timely manner, making the reaction closer to the actual reaction process and thus obtaining the kinetic parameters of the apparent exothermic reaction under thermal runaway conditions.

This calorimeter is mainly used to test the thermal runaway characteristics of large-capacity batteries. In addition to thermal runaway characteristics, it can also measure other thermal properties of large-capacity batteries, such as cycle heat generation characteristics and specific heat capacity. Representative products are shown as follows, including ARC-D9, ARC-D20, ARC-D50, ARC-L120.

Besides, in order to investigate venting behaviors for the tested sample, the calorimeter is sealed in different ways, called sealed accelerating rate calorimeter (sARC). For the Type II sARC, the pressure in the sealed constant volume (CV) vessel will track that in the sealed calorimeter via gas control. The sARC not only retains the functionality of ARC but can also measure the gas venting characteristics of battery thermal runaway, such as gas amount and gas releasing rate. Representative products include sARC-D20s (Type I), sARC-D50s (Type I), and sARC-D100s (Type II).

II. Technical Specifications

2.1 Main Technical Parameters

1. Thermocouples: The calorimeter adopts N-type thermocouples, which are fire-retardant and anti-lag, with good thermoelectric stability and high-temperature oxidation resistance;

2. Calibration: The calorimeter is equipped with calibration function, which is not affected by samples and does not require per-test/repeated calibration. In addition, after calibration, a drift test shall be conducted to verify the temperature control stability of the calibration file, as well as the presence of temperature drift and false exothermic phenomena;

3. Safety protection: The equipment is equipped with a safety pressure relief device to automatically relieve pressure during battery thermal runaway and protect the calorimetric chamber body. The calorimetric chamber body shall not be exposed in the laboratory, and an explosion-proof box shall be installed externally to separate the chamber from operators.

It shall protect against potential chamber explosion and high-speed gas injection to ensure operator safety.

2.2 Main Technical Requirements for Each Sub-system

2.2.1 Main Unit of Accelerating Rate Calorimeter

1.  Equipped with a large-volume calorimeter for large-size power battery testing, tests shall be completed in an explosion-proof box, and equipped with emergency cooling and high-power exhaust systems;

2.  The entire calorimeter system shall operate inside the explosion-proof box;

3.  The explosion-proof box is equipped with an automatic air blower, fully controlled by computer;

4.  The exhaust equipment can be connected to the laboratory's exhaust system; 5. The explosion-proof box is equipped with safety interlock devices controlled by both hardware and software;

6. The explosion-proof box minimizes the potential risk of gas escaping into the laboratory; 7. The system can integrate other calorimeters without adding additional circuits, software or other components;

8. The calorimeter control system can control two or more adiabatic calorimeters with a single set of control system.

2.2.2 Calorimeter Structural Design

1. The calorimeter is made of aluminum with good thermal conductivity, and all inner walls (top, side and bottom) are 20mm thick to ensure sufficient thermal stability;

2.  The calorimeter is equipped with eight heaters, three independent adiabatic control zones, and three independent temperature-control sensors;

3.  The calorimeter chamber incorporates thermal insulation to minimize heat exchange with the external environment;

4.  The calorimeter has explosion-proof and pressure relief design, and adopts magnetic sealing to facilitate automatic pressure relief during battery thermal runaway and protect the calorimetric chamber body.

2.2.3 Battery Nail Penetration Module

1.  Mounted on the side of the calorimeter and directly connected to the inside of the calorimeter;

2.  Nail Penetration Stroke: 100mm, default;

3.  Needle diameter: 3mm;

4.  Number of needles: 10;

5.  Speed range: 1mm/sec to 100mm/sec;

6.  Maximum needle force: 675N;

7.  Fully automatic control and data collection.

2.2.4 Single-Channel Gas Collection System Module

1.  Built-in control software;
2. Built-in supporting circuit;
3. Gas cylinder with volume 300/500/1000mL and built-in control valve;
4. Automatically controlled ball valve switch; 5. Auxiliary gas pipelines, joints and fixing frames.

2.2.5 Software Unit

1.        Equipment operation and control software;

2.        Relevant software required for the workstation;

3.        Data analysis software;

4.        Lifetime free software upgrades for the instrument.

2.2.6 Compliance with Relevant Test Standards

1.        USABC SAND99-0497, July 1999: 3.2 Thermal Stability Tests

2.        SAE J2464-R2009: 4.4.2 Thermal Stability Tests

3.        FreedomCAR SAND 2005-3123: 4.1 Thermal Stability

4.        ASTM E1981-98(2004)

5.        SN/T3078.1-2012 Guidelines for the Evaluation of Thermal Stability of Chemicals - Part 1:Accelerating Rate Calorimeter Method

6.        GB/T-36276 (2023)

2.2.7 Workstation Requirements

1.        Brand: Well-known brand;

2.        CPU: No less than Intel® Xeon® Processor E5-1630 v3 (4C HT, 10MB Cache, 3.7GHz Turbo);

3.        Memory: 16GB (4×4GB) 2400MHz DDR4 RDIMM ECC;

4.        Hard Disk: 500GB 3.5-inch SATA (7,200 Rpm);

5.        Operating System: Windows 10;

6.        Specialized Software: ARC system operation software, ARC data analysis and image processing software.

2.2.8 Other Requirements

1.        The system shall reserve upgrade space for battery testing applications;

2.        Provide 12-month warranty, and lifelong supply of instrument spare parts, technical support and after-sales service.