Battery thermal characteristic measurement system

Product Name: Battery Thermal Characteristics Measurement System Product Model: Model Specification Multiple Product Applications: Suitable for measuring the total amount of heat released during combustion of battery cells; Capable of meeting various types of battery cell samples with capacities below 300Ah, such as cylindrical, soft pack, square hard shell, etc. Manufacturer's price: The model specifications and parameters vary, and the price is also different. Welcome to choose and quote!

1、 Scope of application:

Battery thermal characteristic measurement systemSuitable for measuring the total amount of heat released during combustion of battery cells; Capable of meeting various types of battery cell samples with capacities below 300Ah, such as cylindrical, soft pack, square hard shell, etc.

The design principle is based on the oxygen consumption calculated by the oxygen concentration in the combustion product airflow and the heat release rate during combustion of the products. The heat release rate of a material is also the most important parameter in its combustion performance. This device can accurately measure the heat release rate during the combustion process of materials. This instrument is convenient and accurate for testing, and is extremely important for predicting fire hazards and flame retardant prevention and control measures.

This instrument is customized for non-standard use.

2、 Reference standards:

2.1 Refer to GB/T27904-2011 "Test Method for Combustion Performance of Furniture and Components Ignited by Flames" standard;

2.2 Reference GB/T25207-2010 "Solid Room Fire Test Method for Surface Products in Fire Testing" and ISO9705.1~2:2016 standards

2.3 Refer to GB/T38031-2020 "Safety Requirements for Power Batteries for Electric Vehicles" standard;

2.4 Refer to GB31241-2014 "Safety Requirements for Lithium Batteries and Battery Packs for Portable Electronic Products";

2.5 and BYD's "Blade Battery Safety Requirements"

Designed based on the above standards.

3、 Technical analysis of battery cell combustion:

3.1 Based on the specifications of the battery cell and BYD blade battery (L905mm, H118mm, W13.5mm), the estimated total heat release is 700KW;

3.2 Collection system during battery combustion;

3.2.1 During combustion, all the smoke generated during the test period should be collected, with a sample size of 1m * 0.5m. The collection tower should be 3m * 4.5m to effectively collect all the smoke. According to section 7 of standard ISO9705.1-2016; (GB/T25207 and ISO9705500KW flue gas collection tower is 3m * 3m; The NIST 3 Megawatt Quantitative Heat Release Rate Facility in the United States has a 3MW flue gas collection tower measuring 9m * 12m;

3.2.2 Collection pipeline (i.e. measurement section): required diameter of 0.4m, length of 5m; smoke exhaust capacity greater than 3.5m3/s;

Based on the above technical requirements, our design scheme is as follows:

4、 Main features of the instrument:

4.1 The control part adopts embedded industrial computer control, and the signal collection and processing use 16 bit high-precision board, with an accuracy level of up to 1%, stable performance, and good repeatability.

4.2 Computer Control Interface: Using high-end equipment and instrument professional development software (Labview), the interface is rigorous, with a high degree of automation. All tedious programs and calculations have been integrated into the computer, with very fast response speed, easy operation, user-friendly interface, and foolproof operation.

4.3 Operating software: Windows XP operating interface, Labview style, comprehensive security mechanism. The computer outputs data such as combustion heat release rate, total heat release rate, mass loss rate, smoke release rate, flame propagation index, CO2 generation rate, smoke concentration, etc. Real time display of heat flux time curve, mass flow rate time curve, total heat release rate time curve, carbon dioxide CO2 production, carbon monoxide CO production, smoke production, and surface temperature time curve during testing.

5、 Main performance parameters:

5.1 The whole machine consists of a test stand, weighing device (mass loss), sample trigger source, exhaust ignition device, conical collector, exhaust pipe, measuring device, fan, gas analyzer, etc.

5.2 Test stand and weighing device:

5.2.1 Test stand: length 1200mm, width 500mm; see Figure 2;

5.2.2 Weighing device: with a range of 50kg and an accuracy of 1g, equipped with RS485 output interface, real-time tracking and data acquisition by computer, forming a curve of mass loss and time;

5.2.3 The weighing device is equipped with remote signal transmission function;

5.2.4 The computer receives signals from the weighing device and can monitor and draw real-time curves of quality loss;

5.2.5 The device for testing quality loss has temperature resistance function;

5.2.6 Place the battery on the weighing platform, 127mm ± 76mm above the ground;

5.2.7 The weighing platform is located directly below the geometric center of the collection hood;

5.2.8 The weighing table is 500mm * 500mm.

5.3 Sample trigger source:

5.3.1 External flame ignition trigger source: see the figure below.

5.3.1.1 The external flame ignition trigger source consists of a standard igniter and a gas supply system.

5.3.1.2 The standard igniter housing is welded with 1.0mm steel plate, with dimensions of 170 * 170 * 145mm. The housing is divided into two layers of metal mesh, filled with pebbles and sand respectively. The filling height of the lower layer of pebbles is 100mm, and the upper layer of sand is flush with the upper edge of the igniter. The particle size of sand is 2-3mm, and the particle size of goose pebbles is 4-8mm.

5.3.1.3 Gas source: composed of a bottle group of liquid propane with a purity of not less than 95%, a pressure regulator, a pressure stabilizer, a measuring device, and a gas pipeline.

5.3.2 External heating trigger: see the following figure;

5.3.2.1 Use an electric heating plate for heating and hot burning. Its surface is covered with ceramic metal;

5.3.2.2 Specification: Length 500mm, Width 350mm;

5.3.2.3 Heating power: 3kw;

5.3.2.4 Control method: Control the electric heater through a constant voltage source;

5.3.2.5 Installation position of heating trigger device: Place the heating surface of the heating device in direct contact with the surface of the battery cell.

5.3.3 Acupuncture trigger: as shown in the figure.

5.3.3.1 Composition: composed of a pressure device and a needle tip;

5.3.3.2 Needle Material: Steel;

5.3.3.3 Needle diameter: 3mm~8mm;

5.3.3.4 Needle tip shape: circular hammer shape, with an angle of 20 °~60 °;

5.3.3.5 Acupuncture speed: adjustable from 0.1mm/s to 10mm/s;

5.3.3.6 Acupuncture position and direction: Select the position and direction that can trigger thermal runaway of the battery cell, such as the direction perpendicular to the pole piece

5.3.3.7 Pressure tonnage: 2 tons;

5.3.3.8 Rotating mechanism: using servo motor+ball screw.

5.4 Exhaust ignition device:

5.4.1 The combustible gas emitted during the initial stage of thermal runaway of the tested sample shall be ignited using an external ignition device;

5.4.2 Ignition method: High voltage ignition method, remote control;

5.4.3 Ignition time: 1-10s can be set;

5.4.4 After ignition, this device automatically transfers out of the fire source.

5.5 Cone shaped collection tower: as shown in the figure.

5.5.1 Collect all the smoke generated by battery combustion;

5.5.2 Collection Tower: The bottom size is 3000 * 3000mm and the height is 1000mm. The surface between the bottom and the weighing device is 150mm. The top of the conical collector is a 900 * 900 * 900mm cube. To increase turbulence effect, two 500 * 900mm steel plates are installed in the top cube to form a flue gas homogenizer.

5.6 Smoke exhaust duct: as shown in the figure.

5.6.1 Installed at the outlet of the flue gas mixer, with an inner diameter of 400mm and a straight pipe section of 5M.

5.6.2 Equalizers should be installed at both ends of the straight pipe section to ensure even gas flow inside the pipeline.

The measurement section of the 5.6.3 system should be set at the straight section of the exhaust pipe and the location of the gas uniform mixer.

5.7 Fan:

5.7.1 The exhaust volume is 15000M3/H, which can ensure that the smoke exhaust capacity of the pipeline is greater than 3.5M3/s;

5.7.2 The exhaust volume of the fan is continuously adjustable controlled by a frequency converter;

5.7.3 Fan power: 37kw, AC380V.

5.8 Measurement section:

5.8.1 Gas volume flow measurement device: as shown in the figure.

5.8.1.1 The volumetric flow rate of gas is measured by a bidirectional probe, differential pressure transmitter, and thermocouple with a time constant not exceeding 0.1S. The bidirectional velocity probe and thermocouple should be installed at the center of the pipeline section of the smoke exhaust pipe measurement section. The structure of the bidirectional velocity probe and the differential pressure transmitter should be capacitive, with a resolution of more than ± 1% Pa, a measurement range of 0-2000Pa, and a measurement error of less than 0.5%.

5.8.1.2 The measurement accuracy of volumetric flow rate shall be higher than ± 5%, and the response time of step change (90% of flow rate from initial state to final state) shall not exceed 1 second.

5.8.2 Propane flowmeter: Used for measuring propane mass flow meter (MFC),

5.8.3 Gas Analysis: SERVOMEX 4100 Gas Purity Analyzer

5.8.3.1 Oxygen:

5.8.3.1.1 Measurement Range 0-25% O2

5.8.3.1.2 Measurement principle: Mechanical paramagnetic

5.8.3.1.3 Accuracy:<0.1% O2

5.8.3.1.4 Linearity:<0.1% O2

5.8.3.1.5 Repeatability:<0.1% of reading

5.8.3.1.6 Zero drift/h:<0.002%

5.8.3.1.7 Range drift/h:<0.002%

5.8.3.2 Carbon dioxide and carbon monoxide:

5.8.3.2.1 Measurement Range 0-10% CO2

5.8.3.2.2 Measurement Range 0-1% CO

5.8.3.2.3 Measurement principle: Relevant infrared

5.8.3.2.4 Accuracy:<1% of the measuring range

5.8.3.2.5 Linearity:<1% of the range

5.8.3.2.6 Repeatability:<1% of the range

5.8.3.2.7 Zero drift/week:<2% of the range

5.8.3.2.8 Range drift/day:<1% of reading

5.8.3.2.9 Display: LED LCD

5.8.3.2.10 Analog output: Four channel isolated 4-20mA output

5.8.3.2.11 Output Contact: Six voltage independent single contact outputs (264VAC or 30VDC/1.0A)

5.8.3.2.12 Digital Communication Protocol: RS232/RS485 Modbus

5.8.3.2.13 No flow meter, no built-in filter

5.8.3.2.14 Power supply 170-264Vac, 50Hz

5.9 Gas Sampling System

5.9.1 The gas sampling system consists of a sampling tube, two-stage filters, condenser, stainless steel conduit, sampling pump, sample gas distributor, etc.

5.9.2 The sampling tube is installed on the measuring section of the exhaust pipe, where the gas is evenly mixed. The inlet of the sampling tube is downward to avoid blockage by smoke and debris.

5.9.3 The sampling tube should be made of stainless steel. Before entering the analytical instrument, the gas should undergo secondary filtration (primary 150 µ -200 µ, secondary 3 µ), and the gas sample should be cooled to below 5 ℃. The sampling tube should be as short as possible.

5.9.4 The gas sample is sent to the analytical instrument by a sampling pump. During the sampling process, it is necessary to avoid contamination of the gas sample by oil or similar substances. The sampling pump has a capacity of 10-50L/min, and each gas analyzer consumes 1L/min. The pressure difference generated by the pump is about 10KPa.

The time interval between the gas sample passing through the exhaust pipe and entering the gas analysis instrument should not exceed 1 second.

5.10 Optical Smoke Density Device: As shown in the figure.

5.10.1 Optical Smoke Density Meter: It consists of a light source, lens, photoelectric element, etc. During the measurement process, due to the accumulation of smoke dust, the decrease in light transmittance should not exceed 5%.

5.10.2 Light source: 6V, 10W iodine tungsten lamp, with a filament working temperature of 2900 ± 100K, and a power supply accuracy of ± 2% for the light source.

5.10.3 Lens: A convex lens with a diameter of 50mm and a focal length of 60mm, resulting in a parallel beam diameter of 30MM passing through the exhaust duct.

5.10.4 Optoelectronic receiving element: Single crystal silicon optical element is used to determine smoke density through the change of received beam intensity, and the measurement accuracy of light intensity is not less than ± 5%.

5.10.5 The optical smoke density meter should be installed in a position where the smoke distribution in the exhaust duct is uniform, and the light beam can pass vertically through the exhaust duct. The installation of the optical smoke density meter should not affect speed measurement and sampling. The glass window of the optical smoke density meter should be made of quartz glass.

5.10.6 Measurement range and accuracy of optical receiver: wavelength range (350-1000) mm, adjustable gain, voltage output of 6V, linearity of controller ≥ 99.8%, instability<0.1% Light source receiving accuracy of 0.1%

5.11 Data Collection: The data collection system collects and records experimental data such as oxygen concentration, carbon monoxide concentration, carbon dioxide concentration, temperature, smoke density, heat release rate, and mass loss; The frequency of data collection and processing time is once every 3 seconds;

5.12 Image acquisition: Use a high-temperature resistant camera to take photos of the experimental process.

5.13 Combustion Heat Calibration: For the combustion heat calculated based on the mass and calorific value of propane passing through MFC, the deviation between the two is within 5% according to the principle of oxygen consumption

5.14 Use three sets of 25%, 50%, and 75% filters for automatic calibration, calculate the light intensity passing through the filter, compare the calculated value with the theoretical value of the filter, and ensure that the deviation between the two is within 5%;

5.15 Operating Interface:

6、 Equipment configuration list:

name	Specification, model/technical parameters and performance	brand	quantity
Oxygen analyzer	Concentration range: 0-25%	Import of all-in-one machines and complete machines	1 set
CO2	Measurement range: 0-10%		1 set
carbon monoxide
Photoelectric receiver	Wavelength range: 350-1100nm	Hamamatsu, Japan	1 set
Mass Flow Controller	Flow meter, range: 0~20L/min, accuracy: ± 2%	Seven Star Huachuang	1 set
Micro differential pressure sensor	Signal output: 4-20mA; or 0-5V 200PA	Foshan Haosheng	1 piece
Sampling pump	Diaphragm vacuum pump N86 KTE 6L/min	Qingdao Kedi Bo	1 piece
Smoke and dust filter	JNC QSL-15 0-0.8MPA	Jiangsu Renyi	1 piece
Moisture filter	Drying agent 3KG	Jiangsu Renyi	1 piece
Secondary filter	L=55mm， Circular, white film type, 3um	Jiangsu Renyi	1 piece
centrifugal fan	CY-100 0.045KW 2850R/MIN adjustable exhaust flow rate of 132m ³/h	Foshan Kehui	1 piece
Gear reduction synchronous motor	14W AC220-240V 60KTYZ 10r/min 50HZ/60HZ	Guangdong Zhengke	1 piece
solenoid valve	2W-025-08	AirTAC	1 piece
peristaltic pump	MODLB 220V 5 RPM/MIN	Taiwan	1 piece
module	E4AD	Mitsubishi, Japan	1 piece
pressure gauge	0-2KG	Shanghai Yate	2 of them
Solid state relay	SSR-40DA/40A	Yangming, Taiwan	1 piece
K type thermocouple	1.5MM non exposed hot node Kai installation thermocouple		4 of them
relay	14 pin 220V MY410J	Japan OMRON	7 of them
Pressure regulating valve	AR-2000	AIRTAC	1 piece
board card	USB1616m	Beikong Measurement and Control	3 pieces
Isolation transmitter	50MV-0-5V	Shanghai Kaitai	4 of them
igniter	BY-0247 220v	Guangdong Dingwei	1 set
AC contactor	3210	Shilin, Guangdong	1 piece
computer		associate	1 unit
Aluminum foil paper		Xander	1 roll
optical filter		Qiete	3 pieces
Smoke and dust filter	JNC QSL-15 0-0.8MPA	Jiangsu Renyi	1 piece