Patent Application
20200001125
The present invention relates to a fire containment device for receiving and extinguishing a portable electronic device or other lithium-ion battery powered device that has caught fire.
Portable electronic devices (PEDs), such as smart phones, tablet computers, laptops, e-readers, MP3 players, and electronic toys, are powered by lithium-ion batteries. When improperly handled, manufactured or overcharged, lithium-ion batteries are subject to thermal runaway i.e. the battery spontaneously increases in temperature and begins to vent hot and toxic pressurized gases. This causes the lithium-ion fluid within the battery to ignite and reach temperatures in excess of 2,000 degrees Fahrenheit. While it is possible to extinguish the flames by applying large amounts of water, the lithium inside of the battery may react with the electrolytes and water to generate hydrogen which can accelerate the fire. Sand or other granular minerals can be applied to a lithium-ion battery fire; however, these materials are fire resistant only and do not provide fire extinguishing properties. Accordingly, application of granular minerals to a lithium battery fire is unreliable, ineffective, or impractical.
A lithium-ion battery fire occurring on an aircraft can be catastrophic for obvious reasons. The smoke and toxic vapors alone could create panic on the flight deck and in the passenger cabin. It is therefore critical to provide a means on the aircraft to safely isolate and quickly extinguish a fire of this nature. Current FAA guidelines recommend applying water to a lithium battery fire. However, a sufficient volume of water is not readily available during a flight nor can water be quickly and effectively applied to a lithium-ion battery fires. Although conventional fire extinguishers are provided on an aircraft, they have limited effectiveness against lithium-ion battery fires.
It is known to provide a bag constructed from fireproof and/or fire resistant material to receive an ignited PED and presumably prevent the fire from spreading. Some of these devices use water to cool the ignited battery or chemicals to extinguish the fire. However, none of these devices suppress the fire nor are they capable of containing the heat, smoke or toxic vapors generated when a PED has burst into flames.
A need has therefore existed for a device that allows a user to quickly isolate a PED that has caught fire, prevent the fire from spreading and absorb the smoke and toxic vapor generated during the fire.
The present invention is a device for containing a lithium-ion battery powered PED that has caught fire and extinguishing the fire, the device comprises a container or bag having an opening at one end and a flap or closure for sealing the opening, the interior of the bag includes a liner filled with free-flowing expanded glass granulate having fire extinguishing properties, the liner is compartmentalized to separately retain the free flowing granulate within defined regions and is formed from a sacrificial material that is combustible and will disintegrate when exposed to the heat of a fire whereby when a PED that has caught fire is placed into the bag, the free-flowing expanded glass granulate contained by the liner is caused to be released onto the PED to extinguish the fire and absorb the smoke and gases. In another embodiment, the container is provided as part of a kit that may include tongs, gloves and a blanket to assist a user in placing an ignited PED into the bag or container and securing it into a closed position.
Turning to
A layer 28 is disposed on top of the innermost layer 26. Layer 28 is a silica fiber mat having a high R-value. Layer 28 ensures the exterior of the container C does not overheat during a fire event. This layer is preferably ½ inch in thickness and is capable of withstanding up to 1500 degree Fahrenheit temperatures without degradation. Silica mats having a high R-value within the scope of the present invention for use as layer 28 include those commercially available for use and placement to the exterior of a kiln or similar oven. Although this layer is delicate and fragile to the touch, it is sandwiched within the layers forming the container C and it provides the greatest heat insulation to the device D.
Sandwiched between layer 28 and the outermost layer 24 is a silicone-coated fiberglass fabric 30 that is preferably heat rated for sustained 1000 degree Fahrenheit exposure. This layer is relatively fragile in and of itself but its disposition between the innermost 26 and outermost 24 layers protects it from damage and does not degrade its desired heat resistant property.
Layers 24, 26, 28 and 30, which form the container C portion of the Device D, are sewn together with temperature resistant KEVLAR thread. Exposed seams from the thread may be lined with temperature resistant webbing material such as NOMEX.
The layers forming the flap 14 are as follows. The outermost flap layer 32 is constructed from the above described NOMEX brand webbing which is a flame resistant meta-aramid fabric material. Other flame resistant webbing materials are within the scope of the present invention. Underlying and adjacent the outermost flap layer 32 is interior flap layer 34 which comprises a silicone-coated fiberglass fabric that is preferably heat rated for sustained 1000 degree Fahrenheit exposure. This layer is preferably the same materials as layer 30 noted above. Underlying the interior flap layer 34 is a second interior flap layer 36 in the form of a silica fiber mat having a high R-value. Layer 36 ensures the exterior of the container C does not overheat during a fire event. This layer is preferably ½ inch in thickness and is capable of withstanding up to 1500 degree Fahrenheit temperatures without degradation. Silica fiber mats having a high R-value within the scope of the present invention for use as layer 36 include, for example, those commercially available for use and placement to the exterior of a kiln or similar oven. Although this layer is delicate and fragile to the touch, it is sandwiched within the layers forming the overall flap. The bottom flap layer 38 is a flexible carbon and acrylic coated fiber glass fabric that sufficiently reflect any heat exiting opening 12 during a fire event and therefore prevents the exterior of the flap from overheating. Flap layers 32, 34, 36 and 38 are sewn together with temperature resistant KEVLAR thread. Exposed seams from the thread may be lined with temperature resistant webbing material such as NOMEX.
Turning to
In a preferred embodiment the liner L is constructed from a 100% polyester fabric that has been coated with a PVC resin to increase its sensitivity to heat and flame. Other flammable fabrics and materials (e.g. cotton) are within the scope of the invention.
As best shown in
For example, the tubular compartments shown in the drawings may be square shaped or zig-zag shaped rather than tubular and linear as shown. While it is preferred to provide multiple compartments within the liner L to uniformly distribute the free flowing granulate throughout interior of the container C, the invention can function without compartments. The liner can be variable in size depending upon the size of the device D. The compartments can be formed individually and then sewn together with thread to provide a liner L as generally shown in
The compartments 42 of the liner L are filled with free flowing expanded glass granules 40. The granules are relatively small, lightweight spheres of expanded (i.e. foamed) silicon dioxide glass having interior pores that provide a closed cell structure and about 70-80% air by volume. The granules readily absorb the heat and smoke and actively extinguish the fire by displacing oxygen and melting onto the ignited PED. The size of the aggregate correlates to the interior pore size and hence its relatively low density that enhances its utility as a reactive extinguisher. A commercially available expanded glass granulate suitable for use in the present invention is sold by Dennert Poraver GmbH under the EXTOVER trademark which is incorporated herein by reference.
The size of the expanded glass granulate in the present invention is preferably non-uniform and comprises a blend of different size granules. The smallest size granules have relatively greater density and a smaller pore size while the largest sized granules have the lower density and a larger pore size. In a preferred embodiment, the size of the loose fill granulate is between about 1 mm diameter to about 4 mm in diameter. A suitable composition for the granulate is a blend of 1 mm, 2 mm, 3 mm and 4 mm diameter size spheres combined in a 1:1:1:1 ratio. The preferred blend has a total air content of about 70-80% by volume and an average density of about 10 bs/ft{circumflex over ( )}3 to promote sufficient absorption of the liquid electrolyte in an ignited battery, provide enhanced insulative properties from the heat of the fire and also provide low heat transference. The intense heat generated by a lithium battery fire causes at least some of the granules to melt which encases the PED as the fire is smothered and extinguished.
The use of compartments 42 within the liner L to individually retain the free-flowing granulate serves several functions. It evenly distribute the granulate 40 throughout the liner L and maintains its shape and structure and prevent excessive accumulation of the free flowing granulate within portions of the liner L. Without the compartments the liner would be too flexible and amorphous and thus, not release the granules on a PED fire in a controlled and evenly distributed manner. Compartments that are not sufficiently heated to release granulate onto a PED fire remain unopened and provide ballast to keep the device D surrounded by the fire suppressant granulate.
In the event of a PED fire and as best shown in
As best shown in
Turning to
During a PED fire event, a user will open flap 14 to gain access to opening 12 and then place the ignited PED within the interior of device D. The covering strip 50 is removed from closure means 48 and the ends of the sleeve like extension 46 are joined together to form a seal as best shown in
The filtering device F is shown to comprise an outer perforated gasketed plate 58 and an inner gasketed plate 60 interconnected by screws 58 to provide a passageway 62 that extend from the interior of the container C to its exterior. A commercial grade organic vapor filter 64 is fitted over the inner gasketed plate 60. The filter 64 is shown adjacent the innermost layer 26 of container C and baffles 42. It is within the scope of the present invention to extend or otherwise position the filter so that it is disposed beyond baffles 42 and will lie within the most interior region of container C. As is apparent, it is within the scope of the present invention to provide other filtering devices to filter gas and smoke generated within the bag during a fire event so that it can be released from the bag.
While this invention has been described as having a preferred design, it is understood that it is capable of further modifications, uses and adaptations, both in whole and in part, while following the general principle of the invention including such departures from the present disclosure as is known or customary practice in the art to which this invention pertains, and as may be applied to the central features of this invention.
This application claims the benefit of priority from U.S. Provisional Application Ser. No. 62/691,138 filed on Jun. 28, 2018, which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62691138 | Jun 2018 | US |
