Acrylate filled flame-retardant battery and manufacturing method thereof

Abstract

The invention discloses an acrylic ester filled flame-retardant battery and a manufacturing method thereof. 30-45 parts of acrylic ester, 20-40 parts of ethyl acetate, 10-15 parts of vinyl phosphate, 3-5 parts of sodium sulfamate and 1-3 parts of sodium p-styrenesulfonate are dehydrated and purified to prepare a flame-retardant mixing agent; the preparation method comprises the following steps: adding the raw materials into a mixing reaction kettle in a low-humidity environment at room temperature, mixing, stirring for 2 hours, filling into a sealing barrel, extruding out with inert gas when in use, injecting into a soft package battery which absorbs electrolyte after liquid injection, sealing, putting the battery into a cabinet, and carrying out formation in a hot-pressing formation cabinet, the surface of the battery is filled with the flame-retardant mixing agent, and the flame-retardant mixing agent is melted at high temperature and extruded and flattened by a pressure formation plate, so that a complete flame-retardant covering battery cell is formed in the battery. The surface of the roll core is filled with the acrylate flame retardant, so that the battery is prevented from detonation due to large-area combustion and too high temperature, and the purpose of reducing the combustion risk is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of lithium battery cores, in particular to an acrylate-filled flame-retardant battery and a manufacturing method thereof. Background Art

[0002] Lithium batteries are usually composed of positive / negative electrode materials, electrolytes, diaphragms, and outer shells. The diaphragm prevents the positive / negative electrodes from short-circuiting in the battery, and provides an electrical channel for ion transport during the charging and discharging process. In the event of an accident, the diaphragm and electrolyte in the battery are the main flammable substances, and the performance of the diaphragm has an important impact on the safety of lithium batteries. At present, the main diaphragm material is polyolefin material, which has the defect of poor flame retardancy. Lithium battery cells may inevitably burn when the battery is short-circuited or charged. In order to reduce the risk of combustion, it is usually necessary to consider whether the materials used can reduce the combustion value in battery design. Flame retardant materials are generally added to the electrolyte, but the flame retardant effect is not ideal. Summary of the invention

[0003] The purpose of the present invention is to address the deficiencies in the prior art and provide an acrylate-filled flame-retardant battery and a method for manufacturing the same. By filling the surface of the winding core with an acrylate flame retardant, the battery is prevented from burning over a large area and from exploding due to excessive temperature, thereby achieving the purpose of reducing the risk of combustion.

[0004] The present invention is achieved through the following technical solutions:

[0005] An acrylate-filled flame-retardant battery, comprising the following flame-retardant materials:

[0006]

[0007]

[0008] As a further improvement of the technical solution of the invention, a method for preparing an acrylate-filled flame-retardant battery is provided: 30-45 parts of acrylate, 20-40 parts of ethyl acetate, 10-15 parts of vinyl phosphate, 3-5 parts of sodium aminosulfonate and 1-3 parts of sodium p-styrene sulfonate are dehydrated and purified to prepare a flame-retardant mixture, which is added to a mixing reactor in a low-humidity environment at room temperature and mixed, stirred for 2 hours, and put into a sealed barrel. When used, it is squeezed out with an inert gas and injected into the inside of a soft-pack battery that has been filled with liquid and placed to absorb the electrolyte. After sealing, the battery is placed in a hot pressing cabinet for formation, and the flame-retardant mixture is filled into the battery surface, and is flattened by high-temperature melting and pressure-forming plate extrusion, so that a complete flame retardant-covered battery cell is formed inside the battery.

[0009] As a further improvement of the technical solution of the invention, acrylate, ethyl acetate, vinyl phosphate, sodium aminosulfonate and sodium p-styrenesulfonate are mixed in a low humidity environment, stirred for 2 hours, tested for moisture, and then packed into a sealed barrel for standby use.

[0010] As a further improvement of the technical solution of the invention, the inert gas is injected into the barrel to extrude the flame retardant. The inert gas also needs to be free of moisture and high-purity inert gas is used to prevent the introduction of other heterogeneous reactants.

[0011] As a further improvement of the technical solution of the invention, the flame retardant mixture is injected into the interior of the soft-pack battery that absorbs the electrolyte. The main purpose is not to affect the absorption of the electrolyte. After the flame retardant is injected, the adhesion effect of the flame retardant can be exerted and filled on the surface of the core. The flame retardant mixture is filled between the battery outer sealing packaging material and the core.

[0012] As a further improvement of the technical solution of the invention, after the flame retardant mixture is filled into the battery surface, it melts evenly under the heating of the pressure forming plate and adheres evenly to the surface of the battery core to complete the flat coverage. After the battery cools down, it gradually becomes viscous to isolate the core from the air.

[0013] As a further improvement of the technical solution of the invention, after the battery is pressure-formed, a complete flame retardant is formed to cover the battery cell. The flame retardant inside the battery cell blocks the air, which can effectively reduce combustion and form a safer battery.

[0014] In summary, the present invention has the following beneficial effects:

[0015] The present invention fills the surface of the winding core with an acrylic flame retardant to prevent the battery from burning over a large area and exploding due to excessive temperature, thereby achieving the purpose of reducing the risk of combustion. DETAILED DESCRIPTION

[0016] The present invention will be described in detail below in conjunction with specific embodiments. The illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention.

[0017] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, upper end, lower end, top, bottom...) are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0018] In the present invention, unless otherwise clearly defined and limited, the term "connection" should be understood in a broad sense, for example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0019] In addition, in the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features; in addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0020] An acrylate-filled flame-retardant battery, comprising the following flame-retardant materials:

[0021]

[0022] Specifically, in the present embodiment, a method for preparing an acrylate-filled flame-retardant battery is provided: 30-45 parts of acrylate, 20-40 parts of ethyl acetate, 10-15 parts of vinyl phosphate, 3-5 parts of sodium sulfamate and 1-3 parts of sodium p-styrene sulfonate are dehydrated and purified to prepare a flame retardant mixture, which is added to a mixing reactor in a low humidity environment at room temperature and mixed, stirred for 2 hours, and put into a sealed barrel. When it is used, it is squeezed out with an inert gas and injected into the inside of a soft-pack battery that has been filled with liquid and placed to absorb the electrolyte. After sealing, the battery is placed in a hot pressing forming cabinet (90°C) for formation, and the flame retardant mixture is filled into the battery surface, and is flattened by high-temperature melting and pressure forming plate extrusion, so that a complete flame retardant-covered battery cell is formed inside the battery.

[0023] Specifically, in this embodiment, acrylate, ethyl acetate, vinyl phosphate, sodium aminosulfonate and sodium p-styrenesulfonate are mixed in a low humidity environment, stirred for 2 hours, and after testing the moisture content, they are put into a sealed barrel for standby use.

[0024] Specifically, in the present embodiment, the inert gas is injected into the barrel to extrude the flame retardant. The inert gas also needs to be free of moisture and high-purity inert gas is used to prevent the introduction of other heterogeneous reactants.

[0025] Specifically, in this embodiment, the flame retardant mixture is injected into the interior of the soft-pack battery that absorbs the electrolyte. The main purpose is not to affect the absorption of the electrolyte. After the flame retardant is injected, the adhesion effect of the flame retardant can be exerted and filled on the surface of the core. The flame retardant mixture is filled between the battery outer sealing packaging material and the core.

[0026] Specifically, in this embodiment, after the flame retardant mixture is filled into the battery surface, it melts evenly under the heating of the pressure forming plate and adheres evenly to the surface of the battery core to complete the flat coverage. After the battery cools down, it gradually becomes viscous to isolate the core from the air.

[0027] Specifically, in the embodiment, after the battery is pressure-formed, a complete flame retardant-covered battery cell is formed. The flame retardant inside the battery cell blocks the air, which can effectively reduce combustion and form a safer battery.

[0028] Example:

[0029]

[0030] Example 1

[0031] 35 parts of acrylate, 12 parts of vinyl phosphate, 3 parts of sodium aminosulfonate and 3 parts of sodium p-styrenesulfonate are added to 40 parts of ethyl acetate after dehydration, stirred in a vacuum stirring kettle for 2 hours to mix evenly, and put into a sealed barrel in a low humidity environment at room temperature for standby use to obtain a battery flame retardant. After the battery is injected with liquid, it is placed aside to fully absorb the electrolyte, and then the battery is placed in a dry environment, a notch is cut in the sealing bag, and the flame retardant is injected and sealed. After being placed aside for stability, the battery is placed in a hot pressing cabinet for hot pressing, so that as the temperature rises, the flame retardant is fully and evenly attached to the surface of the battery core. After the formation is completed, the battery is degassed and sealed after cooling. After completing other processes, a flame-retardant battery filled with acrylate can be formed.

[0032] Example 2

[0033] 32 parts of acrylate, 13 parts of vinyl phosphate, 4 parts of sodium aminosulfonate and 2 parts of sodium p-styrenesulfonate are added to 30 parts of ethyl acetate after dehydration, stirred in a vacuum stirring kettle for 2 hours to mix evenly, and put into a sealed barrel in a low humidity environment at room temperature for standby use to obtain a battery flame retardant. After the battery is injected with liquid, it is placed aside to fully absorb the electrolyte, and then the battery is placed in a dry environment, a notch is cut in the sealing bag, and the flame retardant is injected and sealed. After being placed aside for stability, the battery is placed in a hot pressing cabinet for hot pressing, so that as the temperature rises, the flame retardant is fully and evenly attached to the surface of the battery core. After the formation is completed, the battery is degassed and sealed after cooling. After completing other processes, a flame-retardant battery filled with acrylate can be formed.

[0034] Example 3

[0035] 30 parts of acrylate, 15 parts of vinyl phosphate, 5 parts of sodium aminosulfonate and 1 part of sodium p-styrenesulfonate are added to 20 parts of ethyl acetate after dehydration, stirred in a vacuum stirring kettle for 2 hours to mix evenly, and put into a sealed barrel in a low humidity environment at room temperature for standby use to obtain a battery flame retardant. After the battery is filled with liquid, it is placed aside to fully absorb the electrolyte, and then the battery is placed in a dry environment, a notch is cut in the sealing bag, and the flame retardant is injected and sealed. After being placed aside for stability, the battery is placed in a hot pressing cabinet for hot pressing, so that as the temperature rises, the flame retardant is fully and evenly attached to the surface of the battery core. After the formation is completed, the battery is degassed and sealed after cooling. After completing other processes, a flame-retardant battery filled with acrylate can be formed.

[0036] Comparative Example

[0037] Example 4

[0038] 30 parts of acrylate and 15 parts of vinyl phosphate are added to 20 parts of ethyl acetate after dehydration, and stirred in a vacuum stirring kettle for 2 hours to mix evenly, and then put into a sealed barrel in a low humidity environment at room temperature for standby use to obtain a battery flame retardant. After the battery is injected with liquid, it is set aside to fully absorb the electrolyte, and then the battery is placed in a dry environment, a notch is cut in the sealing bag, and the flame retardant is injected and sealed. After being set aside for stability, the battery is placed in a hot pressing cabinet for hot pressing, so that as the temperature rises, the flame retardant is fully and evenly attached to the surface of the battery core. After the formation is completed, the battery is degassed and sealed after cooling. After completing other processes, a battery with acrylate and no additives can be formed.

[0039] Experimental testing and verification

[0040] The battery prepared above was subjected to high temperature (55°C thermal short circuit test). After the battery was fully charged and placed in a test box at a constant temperature of 55°C for 30 minutes, the battery was short-circuited to 0 voltage (<0.5V, i.e. cut off), tested and observed, and the maximum temperature of the battery surface was tested.

[0041] Example Test Results Maximum temperature result Remark Example 1 Smoke, no burning 98℃ OK Example 2 Smoke, no burning 93℃ OK Example 3 Smoke, no burning 87℃ OK Comparative Example 4 smoke, 118℃ NG The effect is not significant No Addition Example There is open flame 138℃ NG

[0042] From the above examples, it can be seen that the batteries of Examples 1, 2 and 3 have significantly improved ignition points, with lower temperatures, while the comparative example has some improvement, but the temperature is higher, while the non-additive example has no significant improvement, short circuits occur at high temperatures, and there is a fire phenomenon, which does not meet safety requirements.

[0043] In summary, the present invention fills the surface of the winding core with an acrylic flame retardant to prevent the battery from burning over a large area and exploding due to excessive temperature, thereby achieving the purpose of reducing the risk of combustion.

[0044] The technical solutions provided by the embodiments of the present invention are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the embodiments of the present invention. The description of the above embodiments is only applicable to help understand the principles of the embodiments of the present invention. At the same time, for those skilled in the art, according to the embodiments of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. An acrylate-filled flame-retardant battery, characterized in that: Includes the following flame retardant materials:

2. A method for making an acrylic ester-filled flame-retardant battery, characterized in that: 30-45 parts of acrylate, 20-40 parts of ethyl acetate, 10-15 parts of vinyl phosphate, 3-5 parts of sodium aminosulfonate and 1-3 parts of sodium p-styrene sulfonate are dehydrated and purified to prepare a flame retardant mixture, which is added to a mixing reactor at room temperature and low humidity and mixed, stirred for 2 hours, and put into a sealed barrel. When used, it is squeezed out with an inert gas and injected into the inside of a soft-pack battery that has been placed to absorb the electrolyte after liquid injection. After sealing, the battery is placed in a hot pressing cabinet for formation, and the flame retardant mixture is filled into the battery surface, which is melted at high temperature and squeezed flat on a pressure forming plate to form a complete flame retardant-covered battery cell inside the battery.

3. The method for manufacturing an acrylic acid ester filled flame retardant battery according to claim 2, characterized in that: Mix acrylate, ethyl acetate, vinyl phosphate, sodium aminosulfonate and sodium p-styrenesulfonate in a low humidity environment, stir for 2 hours, test the moisture content, and then put them into a sealed barrel for later use.

4. The method for manufacturing an acrylic acid ester filled flame retardant battery according to claim 2, characterized in that: The inert gas is injected into the barrel to extrude the flame retardant. The inert gas also needs to be free of moisture and high-purity inert gas is used to prevent the introduction of other heterogeneous reactants.

5. The method for manufacturing an acrylic ester-filled flame-retardant battery according to claim 2, characterized in that: The flame retardant mixture is injected into the interior of the soft-pack battery that absorbs the electrolyte. The main purpose is not to affect the absorption of the electrolyte. After the flame retardant is injected, the adhesion effect of the flame retardant can be exerted and filled on the surface of the core. The flame retardant mixture is filled between the battery outer sealing packaging material and the core.

6. The method for manufacturing an acrylic acid ester filled flame retardant battery according to claim 2, characterized in that: After the flame retardant mixture is filled into the battery surface, it melts evenly under the heating of the pressure forming plate and adheres evenly to the surface of the battery core to complete the flat coverage. After the battery cools down, it gradually becomes viscous to isolate the core from the air.

7. The method for manufacturing an acrylic acid ester filled flame retardant battery according to claim 2, characterized in that: After the battery is pressure-formed, a complete flame retardant is formed to cover the battery core. The flame retardant inside the battery core blocks the air, which can effectively reduce combustion and form a safer battery.

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