Sealed Protective Pouch for Lithium Battery or Small Electronic Device Including a Thermally-Responsive Automatic Fire Suppression Device

Abstract

The present invention relates to a protective sealed bag containing a heat-sensitive automatic fire extinguishing device to prevent fires that may occur due to overheating or explosion of a lithium battery or small electronic device. The bag includes a heat-sensitive fire extinguishing device (possibly an FPC circuit, capsule type, or sticker type, etc.) that operates automatically at high temperatures (approx. 120~135℃) without power supply, inside a main body composed of a heat-resistant and flame-retardant outer shell and an insulating inner shell. When a battery ignites, the bag rapidly releases an inert gas to suppress the fire. The bag includes a relief structure that withstands internal pressure and automatically opens when the pressure exceeds a certain level. It is double-layered with a zipper-lock sealing structure to accommodate the internal pressure of the bag, allowing for easy use by the user. It can be usefully employed as a portable safety device to prevent auxiliary battery fires in crowded spaces such as aircraft and public places.

Description

Technology Field

[0001] The present invention relates to a protective device for preventing fires caused by overheating and explosion of lithium batteries or small electronic devices, and in particular, to a protective sealed bag having a fire extinguishing function that automatically operates in response to high temperatures without a separate power source, including a heat-sensitive automatic fire extinguishing device, and a structure and sealing ability to relieve internal pressure that may occur during the battery explosion and fire extinguishing process. Background Technology

[0002] Lithium-ion batteries are widely used in various electronic devices, particularly portable devices such as power banks and e-cigarettes. Due to their high-density energy storage characteristics, there is a constant risk of fire and explosion caused by overheating, impact, or overcharging. In particular, enclosed spaces such as aircraft, dormitories, and indoors pose a high risk that a fire could lead to casualties and property damage.

[0003] Recently, manual methods such as attaching insulating tape to battery terminals, using terminal caps, or storing them in poly zipper bags have been used for personal portable batteries on aircraft; however, these methods have limitations as they rely entirely on the user's attention and management.

[0004] However, lithium battery explosions are difficult to predict due to various causes such as internal cell defects and thermal runaway, and there is a problem in that it is difficult to respond appropriately using existing methods that lack active fire suppression capabilities. Therefore, there is a growing need for small, user-friendly fire extinguishing devices that can automatically operate and suppress fires without an external power source. The problem to be solved

[0005] The present invention aims to solve the following problems.

[0006] A system is provided that detects fire and automatically extinguishes it without a separate power source, addressing the risk of fire and explosion in batteries.

[0007] It implements a digestion method that is harmless to the human body and environmentally friendly.

[0008] Ensures a safety design that includes airtightness to enhance firefighting efficiency and a structure for relieving internal gases generated during the firefighting process.

[0009] It features a structure suitable for multiple or single-use applications, achieving economic efficiency suitable for mass production.

[0010] It provides a structure that is easy for the general public to use and highly portable.

[0011] Implements practical and low-cost safety protection devices suitable for actual consumption environments. means of solving the problem

[0012] To solve the above problem, the present invention includes the following configuration.

[0013] The envelope of the present invention is a top-opening sealed structure configured to store batteries or to cut off oxygen and extinguish a fire, and is designed to be easy for the general public to use and portable.

[0014] The outer shell is composed of a PET + aluminum composite film (50~70㎛) with heat resistance and flame retardancy, ensuring heat dissipation, fire resistance, and durability.

[0015] The inner lining is composed of an insulating PE film (30–50 µm) and provides electrical insulation and internal protection functions.

[0016] If necessary, a buffer layer or air gap structure (1-3 mm) can be formed between the inner and outer layers.

[0017] The opening of the envelope is configured with a double-sealed structure including a slider-type zipper lock and an auxiliary sealing structure on one side to allow the user to easily insert and remove the battery, and a polyamide zipper with high heat resistance and adhesion, a slide lock type, or a PE+PET composite material may be used.

[0018] The corners of the bag are treated with a curved structure, so even if the bag expands during extinguishing, pressure is not concentrated, and it performs a buffering function that induces the dispersion of extinguishing gas.

[0019] The ends and joints of the envelope are manufactured using heat fusion or ultrasonic bonding methods and are finished with a high-strength pattern based on an average internal pressure of 0.7 bar or higher to withstand increased internal pressure.

[0020] Inside, a heat-sensitive automatic fire extinguishing device is fixedly attached to the inner lining at the top of the bag, and the operating temperature is set to approximately 120–135°C. This device is configured to operate without an external power source, and when the internal temperature reaches the set temperature, it releases a built-in fire extinguishing agent through physical rupture or a chemical reaction. The fire extinguishing device can be implemented using heat-sensitive materials or circuit-based (including FPC), includes sticker-type or capsule-type structures, and the released fire extinguishing agent is HFC-227ea, FK-5-1-12, or a functionally equivalent inert gas.

[0021] When the internal temperature reaches 120 to 135°C in the event of a battery explosion or fire, the fire extinguishing device activates within 1 second to spread extinguishing gas, and the fire can usually be extinguished within 5 to 10 seconds due to the decrease in oxygen concentration inside the sealed bag.

[0022] The internal gas diffusion scenario is as follows.

[0023] ① If the internal temperature rises due to overheating of the battery or electronic device inside the envelope,

[0024] ② The heat-sensitive fire extinguishing device automatically starts releasing extinguishing gas when it reaches the operating temperature.

[0025] ③ Fire extinguishing gas is dispersed within the enclosed internal space, and the fire is suppressed due to the decrease in oxygen concentration.

[0026] ④ When the bag expands, the outer and inner layers perform heat insulation and pressure resistance functions, and the zipper lock can minimize gas leakage.

[0027] ⑤ Residual gas remains inside, suppressing re-ignition and cooling the ignition source.

[0028] The pressure relief structure is designed with a relief structure and internal buffer located at the top or side of the bag to prevent rupture caused by bag expansion due to battery thermal runaway or gas ejection during a fire or firefighting process. The relief opens gradually when the internal pressure reference pressure (approx. 0.3 to 0.5 bar) is reached, and may be configured to selectively rupture a weakened thermal joint to maintain an internal oxygen dilution state and residual firefighting gas effect; the area may include a finishing line or linear rupture pattern and micro-venting holes designed with heat resistance and pressure resistance in mind.

[0029] If necessary, a color-changing indicator can be attached to the outside of the envelope to enable visual identification of usage status or abnormalities.

[0030] The above-mentioned envelope is defined based on structural function, and its specific size and shape can be freely modified according to the type, size, and capacity of the items to be stored. Generally, 20 to 30 percent of the space relative to the size of the items is secured to maximize the diffusion of extinguishing gas and the oxygen blocking effect. Effects of the invention

[0031] It is possible to suppress explosions and fires that may occur in small lithium batteries, such as power banks, in advance and prevent fires.

[0032] The fire extinguishing function can be automatically activated in the early stages of a fire without user intervention through the response of the heat-sensitive automatic fire extinguishing device.

[0033] It does not require an external power source, so there is no risk of failure.

[0034] It is harmless to the human body and possesses versatility, allowing it to be used even in sensitive environments such as on airplanes and in public places.

[0035] It possesses economic feasibility suitable for mass production, distribution, and public procurement due to its low-cost production structure.

[0036] It can be utilized in various fields such as public safety kits, airlines, and electronics OEMs, and possesses industrial scalability that allows for flexible application to subsequent products. Brief explanation of the drawing

[0037] FIG. 1 is a front structural diagram including an outer shell, inner shell, heat-sensitive automatic fire extinguishing device, battery location, zipper lock, and relief zone configuration. Figure 2 includes the relationship of components, placement location, joints, and relief zone configuration of the cross-sectional structural diagram. Figure 3 shows the relationship between the re-layer and components in a separated cross-sectional view and an envelope cross-sectional view. Figure 4 is an enlarged detailed view of the relief structure, showing the method of configuring the relief zone and the internal pressure flow. Figure 5 is a conceptual diagram of the operation of a heat-sensitive automatic fire extinguishing device. 6 indicates the size change and functional component change according to the amount of battery stored for Example 1 (when storing one auxiliary battery) and Example 2 (when storing three auxiliary batteries). Specific details for implementing the invention

[0038] The present invention relates to a sealed bag equipped with a heat-sensitive automatic fire extinguishing device so as to automatically suppress fires caused by overheating and explosion of lithium batteries or small electronic devices.

[0039] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention is not limited to the embodiments presented, and while the present invention is defined primarily by structural function, the specific size and shape can be freely modified according to the type, size, and capacity of the storage object through the addition, modification, deletion, or addition of components.

[0040] Figure 1 is a front structural diagram of a sealed bag equipped with a heat-sensitive automatic fire extinguishing device.

[0041] The envelope body (10) is composed of an outer shell (11) of a PET + aluminum composite film (50~70㎛) having heat resistance and flame retardancy, and an inner shell (12) of a PE film (30~50㎛) having insulation properties.

[0042] Between the inner and outer layers, a buffer layer or an air layer (18) of an air gap may optionally be included to absorb expansion when internal pressure rises and prevent the envelope from bursting.

[0043] A space (14) for storing an auxiliary battery is provided inside the envelope, and a heat-sensitive automatic fire extinguishing device (13) is attached to the top of the inner lining so as to be separated from it.

[0044] A double-structured slider-type zipper lock (15) is located at the top, allowing the user to easily open and close the bag. When sealed, it maintains low oxygen levels and minimizes the leakage of fire extinguishing gas when the fire extinguishing device is activated due to a battery explosion or fire.

[0045] The fire extinguishing device (13) automatically operates when it reaches a temperature of 120 to 135°C without external power, releases an inert gas (HFC-227ea, FK-5-1-12, etc.), and suppresses a fire in a sealed space.

[0046] Referring to the operation concept diagram of the heat-sensitive automatic fire extinguishing device in FIG. 5, ① the user opens the opening (15) of the bag, places the auxiliary battery into the bag, and seals the bag with a double zipper lock (15). ② When the internal temperature reaches 120~135℃ in the event of a battery explosion or fire, ③ the fire extinguishing device (13) attached to the inner lining (12) operates within 1 second to release inert fire extinguishing gas. This gas diffuses into the sealed space inside the bag, dilutes the oxygen concentration, and suppresses the fire. Typically, the fire can be extinguished within 5 to 10 seconds due to the reduction in oxygen concentration inside the sealed bag, and ④ the fire extinguishing gas remaining inside the bag prevents re-ignition and maintains the extinguished state.

[0047] A relief zone (16) is provided at the top corner or side of the envelope, which automatically ruptures or opens to release minimal pressure to prevent the fire extinguishing bag from bursting when the set internal pressure (e.g., 0.5 to 0.7 bar) is exceeded, thereby relieving the internal pressure. Referring to the detailed relief structure for releasing pressure when internal pressure is generated in the envelope in FIG. 4, a joint (17) is provided around the relief zone so that the relief zone does not expand due to pressure.

[0048] FIG. 2 is a cross-sectional view. The ends and joints (17) of the envelope are manufactured by heat fusion or ultrasonic bonding and are finished with a high-strength pattern based on an average internal pressure of 0.7 bar or higher to withstand an increase in internal pressure. The corners of the envelope are treated with a curved structure (19) so that pressure is not concentrated even when the envelope expands during extinguishing, and perform a buffering function that induces the dispersion of extinguishing gas.

[0049] If necessary, a color-changing indicator (20) is attached to the outside of the envelope to allow identification of whether the fire extinguishing device is operating.

[0050] The bag can be configured as single-use or reusable and is manufactured to provide 20 to 30 percent of extra space relative to the volume of the items stored inside.

[0051] In the embodiment of FIG. 6, an envelope of approximately 15 cm × 22 cm can be designed to accommodate one auxiliary battery, but the scope of the invention is not limited to a specific size and is defined by functional components.

[0052] Example 1: Capacity of approximately 1 liter, external dimensions of approximately 15 cm in width and 22 cm in height. Storage of one auxiliary battery. Fire extinguishing device (13) HFC-227ea approximately 3 g patch type attached (5×5 cm), estimated maintenance pressure 0.6~0.7 bar, estimated fire extinguishing gas release amount approximately 0.4 liters. Gas injection starts within approximately 1 second after operation, and pressure inside the bag is maintained for approximately 5 to 10 seconds. (Top of FIG. 6)

[0053] Example 2: Capacity of approximately 2.5 liters, external dimensions of width approximately 30 cm, height approximately 22 cm, and bottom width approximately 3 cm. Storage of up to 3 auxiliary batteries. The fire extinguishing device (13) has a dispersed fire extinguishing patch structure (2 to 3 arranged), a total HFC-227ea usage of approximately 6 to 9 g, and an estimated operating pressure of around 0.8 bar. Designed with 2 relief zones, including an internal buffer layer, and ensures an internal gas residence time of approximately 10 to 15 seconds. (Bottom of FIG. 6) Industrial applicability

[0054] This invention can be utilized in various environments, including for general consumers, transportation, and industrial use. It can be widely applied in diverse industrial sectors, such as the storage and transportation of lithium-ion batteries, aircraft mounting, safety kits for public distribution, components for the shipment of electronic devices, and product packages for corporate delivery. Furthermore, future applications can be expanded in various ways, such as reusability, miniaturization, embedded design, and modularity. Explanation of the symbols

[0055] 10: Protective envelope body (the main body part forming the overall envelope structure) 11: Outer shell (composed of a PET + aluminum composite film (50~70㎛) with heat resistance and flame retardancy, ensuring heat dissipation, fire resistance, and durability) 12: Inner lining (composed of a flexible PE film (30~50㎛), providing electrical insulation and internal protection) 13: Thermal extinguishing device (attached to the inner lining at the top of the bag and implemented as a thermal material or circuit-based (including FPC) that releases an embedded extinguishing agent through physical rupture or chemical reaction when it reaches a temperature of approximately 120–135°C without external power, and includes sticker-type or capsule-type structures, wherein the released extinguishing agent is HFC-227ea, FK-5-1-12, or a functionally equivalent inert gas) 14: Location of the battery compartment in the interior space (the location within the bag where the battery is inserted) 15: Ziploc (Uses a double ziplock for opening and sealing the bag opening) 16: Relief Zone (Gradually opens at a certain pressure to prevent the bag from tearing in preparation for bag expansion caused by battery thermal runaway or gas release during fire or extinguishing processes) 17: Joint (Manufactured by thermal fusion or ultrasonic bonding, and finished with a high-strength pattern based on an average internal pressure of 0.7 bar or higher to withstand increased internal pressure) 18: Buffer layer or air gap (1–3 mm can be formed between the inner and outer layers if necessary) 19: Curved edges (Designed with a curved structure to prevent pressure concentration even when the bag expands during extinguishing, and to perform a buffering function that induces the dispersion of extinguishing gas) 20: Indicator (If necessary, a color-changing indicator is attached to the outside of the envelope to allow visual identification of usage status or abnormalities)

Claims

Claim 1 A protective device for preventing fire in a lithium battery or small electronic device comprising: (a) an internal space capable of accommodating a lithium battery or small electronic device; (b) a sealed envelope body composed of an outer shell having heat resistance and flame retardancy and an inner shell having insulation; (c) a heat-sensitive automatic fire extinguishing device attached to the interior of the envelope body and releasing an inert fire extinguishing agent through physical rupture or chemical reaction in response to a temperature of approximately 120 to 135°C without external power; (d) a slider-type zipper or double sealing structure for opening and closing the envelope body; and (e) a relief structure for automatically opening or rupturing to release internal gas to the outside when the internal pressure of the envelope rises above a set level, wherein the fire extinguishing device is implemented as at least one of an FPC-based circuit, a heat-sensitive capsule, or a sticker-type fire extinguishing patch, and the released fire extinguishing agent is HFC-227ea, FK-5-1-12, or a functionally equivalent inert gas harmless to the human body, wherein the lithium battery or Sealed envelope for protecting small electronic devices. Claim 2 A protective sealed envelope according to claim 1, characterized by having a top-opening sealed structure configured to store a battery or to cut off oxygen and extinguish a fire, and being easy for the general public to use and portable. Claim 3 A protective sealed envelope according to claim 1, wherein the outer shell of the envelope is composed of a PET and aluminum laminated film, the inner shell is composed of PE or a polymer material having an electrical insulation function, and the two materials are integrated by a heat fusion or ultrasonic bonding method. Claim 4 A protective sealed envelope according to claim 1, characterized in that a cushioning layer or an air gap is installed between the outer shell and the inner shell of the envelope if necessary. Claim 5 A protective sealed envelope according to claim 1, characterized in that the corners of the envelope are treated with a curved structure to mitigate the risk of damage when internal pressure increases and to perform a cushioning function that induces the dispersion of extinguishing gas. Claim 6 A protective sealed bag according to claim 1, characterized in that a heat-sensitive fire extinguishing device is attached to the top of the inner lining of the bag and releases an inert fire extinguishing agent within a few seconds in response to a temperature of about 120 to 135°C. Claim 7 A protective sealed envelope according to claim 1, characterized in that the heat-sensitive automatic fire extinguishing device is implemented as a sticker-type, capsule-type, or multi-capsule-type structure using an FPC (flexible printed circuit board)-based sensor or a film-type thermal reaction device and can be distributed and disposed at multiple locations inside the envelope. Claim 8 A protective sealed envelope according to claim 1, wherein the relief structure is formed with a micro discharge hole or a durable pattern or linear rupture structure that selectively ruptures at a set pressure so as to automatically open when the internal temperature or pressure of the envelope exceeds a set reference value. Claim 9 A protective sealed envelope according to claim 1, characterized in that the envelope is formed to have a clearance of 20 to 30 percent relative to the volume of the object to be stored, thereby improving gas dispersion and oxygen blocking effects. Claim 10 A protective sealed envelope according to claim 1, wherein the envelope can be selectively manufactured as a single-use or multi-use envelope, and is characterized by having an indicator attached that is a status indicator or a color-changing mark to identify whether it is reusable, thereby allowing visual confirmation of whether the fire extinguishing device is operating or the time for replacement. Claim 11 A protective sealed envelope according to claim 1, characterized in that the envelope is intended to prevent the risk of lithium battery fire in public crowded spaces such as aircraft cabins, dormitories, hospitals, schools, subways, or environments for storing personal portable electronic devices.

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