阅读说明：本技术 一种锂离子电池燃烧对环境污染的检测方法 (Method for detecting environmental pollution caused by lithium ion battery combustion ) 是由 李向梅 乔羽 高飞 杨荣杰 杨凯 王康康 于 2018-09-07 设计创作，主要内容包括：一种锂离子电池燃烧对环境污染的检测方法,该检测方法包括如下步骤：1)备电池样品；2)燃烧器中燃烧所述样品；3)分析燃烧后的气体。本发明提供的检测方法通过对锂离子电池整体燃烧及其隔膜、电解质的完全燃烧所得产物的分析,确定了锂离子电池的燃烧产物毒性,可以由局部到整体对锂离子电池的各部分燃烧产物毒性进行有效地评估,操作简便,分析全面且检测结果准确可靠。(A method for detecting environmental pollution caused by lithium ion battery combustion comprises the following steps: 1) preparing a battery sample; 2) combusting the sample in a burner; 3) the combusted gases were analyzed. The detection method provided by the invention determines the toxicity of the combustion products of the lithium ion battery by analyzing the products obtained by the integral combustion of the lithium ion battery and the complete combustion of the diaphragm and the electrolyte of the lithium ion battery, can effectively evaluate the toxicity of the combustion products of each part of the lithium ion battery from local parts to the whole parts, and has the advantages of simple and convenient operation, comprehensive analysis and accurate and reliable detection results.)

1. A method for detecting environmental pollution caused by lithium ion battery combustion is characterized by comprising the following steps:

1) preparing a battery sample;

2) combusting the sample in a burner;

3) the combusted gases were analyzed.

2. The inspection method of claim 1, wherein the burner comprises: the device comprises a base, a combustion chamber and a control chamber;

the control chamber comprises a smoke density tester, a temperature sensor, a temperature controller, an optical sensor and a control panel which are connected with the combustion chamber;

the combustion chamber comprises a box body movably connected to a front door, a sample rack, a heat radiation source and an optical assembly.

3. The inspection method of claim 2, wherein said front door is provided with a viewing window;

the box body comprises an explosion-proof membrane and a smoke outlet which are arranged at the bottom, an air outlet at the rear side of the bottom, an air inlet at the top and a sampling port;

the sample rack is provided with a sample box;

the heat radiation source is fixed on the explosion-proof membrane by a heat radiation source bracket.

4. The inspection method according to claim 2, wherein the optical module includes a light source emitting port and a light source receiving port aligned in a vertical direction;

the light source emitting port is positioned at the bottom of the test box, and a lower light window is arranged on the light source emitting port; a light-tight lower camera bellows is arranged below the lower light window, the lower camera bellows is arranged in the base, and a light source and a lens are sequentially arranged in the lower camera bellows from bottom to top;

the light source receiving port is positioned at the top of the test box, an upper light window is arranged on the light source receiving port, a lightproof upper dark box is arranged above the upper light window, and an optical filter and a photoelectric detector are arranged in the upper dark box;

and a connecting polished rod is arranged between the lower light window and the upper light window.

5. The detection method of claim 2, wherein the detection method comprises recording the irradiance at 25kw/m as indicated by the smoke density tester²The combustion chamber (2) was used to burn a monolithic battery of 75X 75mm specification at smoke densities of 1.5min and 4 min.

6. The inspection method of claim 1, wherein said burner comprises a tubular horizontal burner and a heating element;

one end of the combustion furnace is plugged with a pipe plug, the other end of the combustion furnace is provided with an air outlet pipe, and the thermocouple is arranged in the furnace in a penetrating way and extends to a constant temperature area;

both ends of the heating element are led out through the combustion furnace.

7. The method of claim 6, wherein a battery separator with an electrolyte having a mass of 1g is burned in the tubular combustion furnace preheated to 600 ℃, and the gas burned for 10min is collected with a gas bag to be measured.

8. The method of claim 7, wherein the CO and CO are detected using a non-dispersive infrared detector₂And (4) content.

9. The detection method according to claim 7, wherein the gas is introduced in accordance with gas bag-halogen tube-SO₂-HCN-pump cartridge;

airbag-NO_xThe gas pumping cylinder is sequentially connected with a gas detection pipe to detect gas composition.

10. The detection method according to claim 8 or 9, wherein the air bag comprises a bag body, a bag mouth, a sealing plug and a bag mouth cover having a tamper-proof fixing structure;

the bag mouth comprises an air hole and a bag shoulder;

the bag body is sealed on the bag shoulder;

the bag mouth cover with the anti-unsealing fixing structure is fixed on the bag mouth.

11. The detection method of claim 7, further comprising the steps of:

①, absorbing the gas burnt in the tube furnace for 20min by 10mol/L sodium hydroxide solution;

②, diluting the sodium hydroxide solution absorbed the combustion products, detecting the content of each gas by ion chromatography at 25 ℃ and recording.

Technical Field

The invention relates to the field of gas toxicity evaluation, in particular to a method for detecting environmental pollution caused by lithium ion battery combustion.

Background

With the wide use of electric automobiles, the phenomenon of frequent fire of the electric automobiles appears, and the combustion characteristics of the electric automobiles are rapid combustion, long duration, high combustion temperature, violent combustion and release of a large amount of toxic and harmful gases in the combustion process. The electric automobile is usually caused by the power battery pack, which is generally a lithium ion battery. When the organic matters in the materials for the lithium ion battery have safety accidents such as thermal runaway and the like, more toxic and harmful gases can be leaked, which can bring immeasurable harm to personnel and environment.

At present, the toxicity and content of gases generated by combustion of a lithium ion battery are not clear, but are closely related to various materials in the battery, particularly materials of a diaphragm and electrolyte, so that a comprehensive detection method for the toxicity of combustion products of the lithium ion battery is required to be provided, and further, the safety of the lithium ion battery is effectively and safely analyzed.

Disclosure of Invention

The invention aims to provide a method for detecting environmental pollution caused by lithium ion battery combustion.

In order to achieve the purpose, the invention adopts the following technical scheme:

a detection method for environmental pollution caused by lithium ion battery combustion comprises the following steps:

1) preparing a battery sample;

2) combusting the sample in a burner;

3) the combusted gases were analyzed.

Preferably, the burner includes: the device comprises a base, a combustion chamber and a control chamber;

the control chamber comprises a smoke density tester, a temperature sensor, a temperature controller, an optical sensor and a control panel which are connected with the combustion chamber;

the combustion chamber comprises a box body movably connected to a front door, a sample rack, a heat radiation source and an optical assembly.

Preferably, a visual window is arranged on the front door;

the box body comprises an explosion-proof membrane and a smoke outlet which are arranged at the bottom, an air outlet at the rear side of the bottom, an air inlet at the top and a sampling port;

the sample rack is provided with a sample box;

the heat radiation source is fixed on the explosion-proof membrane by a heat radiation source bracket.

Preferably, the optical assembly comprises a light source emitting port and a light source receiving port which are aligned in the vertical direction;

the light source emitting port is positioned at the bottom of the test box, and a lower light window is arranged on the light source emitting port; a light-tight lower camera bellows is arranged below the lower light window, the lower camera bellows is arranged in the base, and a light source and a lens are sequentially arranged in the lower camera bellows from bottom to top;

the light source receiving port is positioned at the top of the test box, an upper light window is arranged on the light source receiving port, a lightproof upper dark box is arranged above the upper light window, and an optical filter and a photoelectric detector are arranged in the upper dark box;

and a connecting polished rod is arranged between the lower light window and the upper light window.

Preferably, the detection method comprises recording the illuminance at radiation of 25kw/m indicated by the smoke density tester²In the combustion box, the whole with the combustion specification of 75 multiplied by 75mmSmoke density at 1.5min and 4min of the cell.

Preferably, the burner comprises a tubular horizontal burner and a heating element;

one end of the combustion furnace is plugged with a pipe plug, the other end of the combustion furnace is provided with an air outlet pipe, and the thermocouple is arranged in the furnace in a penetrating way and extends to a constant temperature area;

both ends of the heating element are led out through the combustion furnace.

Preferably, 1g of battery diaphragm with electrolyte is burned in the tubular combustion furnace preheated to 600 ℃, and the gas burned for 10min is collected by a gas bag to be tested.

Preferably, the CO and CO are detected using a non-dispersive infrared spectrometer₂And (4) content.

Preferably, according to airbag-halogen tube-SO₂-HCN-pump cartridge;

the air bag-NOx-air exhaust cylinder is sequentially connected with a gas detection pipe to detect gas.

If the HCN colorimetric tube is changed from yellow to pink, the measured gas is proved to contain HCN; if SO₂The color comparison tube turns from pink to yellow, which proves that the measured gas contains SO₂(ii) a If the vision of the halogen detecting tube is changed from white to light red, the detected gas is proved to contain halogen; if NO_xThe color comparison tube changes from white to light purple, which proves that the measured gas contains NO_x。

Preferably, the air bag comprises a bag body, a bag mouth, a sealing plug and a bag mouth cover with a tamper-proof fixing structure;

the bag mouth comprises an air hole and a bag shoulder;

the bag body is sealed on the bag shoulder;

the bag mouth cover with the anti-unsealing fixing structure is fixed on the bag mouth.

Preferably, the detection method further comprises the following steps:

①, absorbing the gas burnt in the tube furnace for 20min by 10mol/L sodium hydroxide solution;

②, diluting the sodium hydroxide solution absorbed the combustion products, detecting the content of each gas by ion chromatography at 25 ℃ and recording.

Preferably, the comprehensive smoke density, the content of CO, CO2 and other gases are evaluated for the pollution of the combustion of the lithium ion battery to the environment.

Compared with the closest prior art, the technical scheme provided by the invention has the following beneficial effects:

the detection method provided by the invention determines the toxicity of the combustion products of the lithium ion battery by analyzing the products obtained by the integral combustion of the lithium ion battery and the complete combustion of the diaphragm and the electrolyte of the lithium ion battery, can effectively evaluate the toxicity of the combustion products of each part of the lithium ion battery from local parts to the whole parts, and has the advantages of simple and convenient operation, comprehensive analysis and accurate and reliable detection results.

The explosion-proof membrane is arranged at the bottom of the combustion furnace and the pressure relief opening is formed in the top of the combustion furnace, so that the operation safety is improved.

The tubular horizontal combustion furnace used in the detection method provided by the invention has the advantages of small volume, low cost and quick temperature rise.

The detection method provided by the invention uses a novel air bag, is pressure-resistant and leak-free, and can more accurately detect the components and the content of the gas.

Drawings

FIG. 1 is a smoke density curve of the overall combustion of a lithium ion battery in example 1 of the present invention;

FIG. 2 is a structural view of a burner used in the present invention

FIG. 3 is a top view of a burner used in the present invention

FIG. 4 is a schematic view showing the structure of a can type burner used in the present invention

FIG. 5 is a partial cross-sectional view of an air bag used in the present invention

Wherein: the device comprises a base 1, a combustion chamber 2, a box body 3, a control chamber 4, a control panel 41, a heat radiation source 5, a radiation source support 51, a sample box 6, a sample holder 61, an optical component 7, a dark box 71, a dark box 72, a connecting polished rod 73, a front door 8, a visual window 81, a pressure relief port 9, a smoke exhaust port 10, a smoke exhaust pipeline 11, a sampling port 12, an air inlet 13, an explosion-proof membrane 14, a furnace tube 15, a hearth 16, a heating element 17, an air outlet 18, a binding post 19, a thermocouple 20, a pipe plug 21, a bag body 22, a bag mouth 23, a sealing plug 24 and a bag mouth cover 25.

Detailed Description

The technical solution of the present invention will be described in detail with reference to the accompanying drawings and specific embodiments.

The device used in the invention comprises:

1. as shown in fig. 2 to 3, the burner includes: the device comprises a base, a combustion chamber and a control chamber;

the control chamber comprises a smoke density tester, a temperature sensor, a temperature controller, an optical sensor and a control panel which are connected with the combustion chamber;

the combustion chamber comprises a box body movably connected to a front door, a sample rack, a heat radiation source and an optical assembly.

A visual window is arranged on the front door;

the anti-explosion film is arranged on the surface of the inner bottom of the box body, a smoke exhaust port connected with a smoke exhaust channel penetrating through the base is arranged at the bottom of the box body, an air outlet is formed in the bottom of the back of the box body, an air inlet is formed in the top of the box body, and a sampling port is arranged at the top of the box body;

a sample box is fixedly arranged on the sample frame;

the heat radiation source is fixed on the explosion-proof membrane by a heat radiation source bracket;

the optical assembly comprises a light source emitting port and a light source receiving port which are aligned in the vertical direction;

the light source emitting port is positioned at the bottom of the test box, and a lower light window is arranged on the light source emitting port; a light-tight lower camera bellows is arranged below the lower light window, the lower camera bellows is arranged in the base, and a light source and a lens are sequentially arranged in the lower camera bellows from bottom to top;

the light source receiving port is positioned at the top of the test box, an upper light window is arranged on the light source receiving port, a lightproof upper dark box is arranged above the upper light window, and an optical filter and a photoelectric detector are arranged in the upper dark box;

and a connecting polished rod is arranged between the lower light window and the upper light window.

2. As shown in FIG. 4, another burner of the present invention comprises a furnace chamber, a furnace tube disposed in the furnace chamber, and a heating element wound around the furnace tube;

one end of the furnace tube is plugged with a tube plug, the other end of the furnace tube is provided with an air outlet tube, and the thermocouple is arranged in the furnace tube in a penetrating way and extends to a constant temperature area of the furnace tube;

two ends of the heating element are led out from the furnace cavity through the furnace tube, and two ends of the furnace tube extend out of the furnace cavity.

3. As shown in fig. 5, the air bag used in the present invention comprises an aluminum foil bag body, a bag mouth, a sealing plug and a bag mouth cover having a tamper-proof fixing structure;

the bag mouth upper portion is the cavity that the center is equipped with the gas pocket to link to each other with the lower part cavity through the gas pocket, sets up the bag shoulder in the outside around the lower part cavity, the sealing plug of filling in the lower part cavity closely cooperates and seals the gas pocket with the lower part cavity, and the aluminium foil bag body seals connects on the bag shoulder, and the bag mouth lid that has the fixed knot of preventing unsealing constructs is fixed on the bag mouth.

Second, the embodiment of the invention: