Patent Application
20220223947
The present invention in general relates to a high strength, light weight battery containment system and in particular to a high strength, light weight puncture resistant shield of such a containment system that provides additional protection to the containment system from road debris.
Weight savings in the automotive, transportation, aerospace, and logistics-based industries has been a major focus in order to make more fuel-efficient vehicles both for ground and air transport. In order to achieve these weight savings, light weight composite materials have been introduced to take the place of metal structural and surface body components and panels. Composite materials are materials made from two or more constituent materials with significantly different physical or chemical properties, that when combined, produce a material with characteristics different from the individual components. The individual components remain separate and distinct within the finished structure. A composite material may be preferred for reasons that include materials which are stronger, lighter, or less expensive when compared to traditional materials of steel or aluminum. Still another advantage over metals is reduced corrosion, leading to longer operational life and reduced maintenance costs.
Composites typically have two constituent materials: matrix and reinforcement. The matrix material surrounds and supports the reinforcement materials by maintaining their relative positions. The reinforcements impart their special mechanical and physical properties to enhance the matrix properties. A synergism produces material properties unavailable from the individual constituent materials, while the wide variety of matrix and strengthening materials allows the designer of the product or structure to choose an optimum combination.
The use of fiber inclusions to strengthen a matrix is well known to the art. Well established mechanisms for the strengthening of a matrix include slowing and elongating the path of crack propagation through the matrix, as well as energy distribution associated with pulling a fiber free from the surrounding matrix material. In the context of sheet molding composition (SMC) formulations, bulk molding composition (BMC) formulations, and resin transfer molding (RTM) fiber strengthening has traditionally involved usage of chopped glass fibers, while carbon fibers are known to be high strength and low weight reinforcements.
Weight savings are particularly important for electric and hybrid vehicles powered with energy cells employing battery technologies in order to achieve greater vehicle driving range per charge. However, unique problems associated with some components of electric and hybrid vehicles have hindered the ability to use composite materials for some applications on hybrid or electric vehicles. For example, batteries of electric and hybrid vehicles present unique safety considerations owing to the high voltages of the batteries, chemicals employed in the battery technologies, combustion and fire risks associated with the batteries, and potential fume encounters if the batteries are broken or damaged. Therefore, batteries of electric and hybrid vehicles generally require protective containers designed to shield batteries from forces they may otherwise experience during an impact or crash event.
Generally, such protective containers are high strength boxes formed of welded metals, which are heavy, prone to corrosion, and have been found to be water penetrable at least at the welds. Attempts have been made to form protective battery containers from composite materials to reduce the weight of such containers. However, such containers are usually joined with metal bolts, which require additional machining of through holes in the composite material of the container, which is difficult because of the high strength of the material through which the holes must be drilled, placement of the bolts in the through holes, and securing of the bolts with nuts, leading to complex manufacturing techniques, slow manufacturing throughputs, and high manufacturing costs. Additionally, the designs of typical battery containment boxes are generally focused on protecting batteries from side impact forces they may experience during an impact or crash event, while failing to provide sufficient protection of the batteries contained therein from other potential damage such as an impact or impalement of road debris during normal operating conditions.
Thus, there exists a need for a puncture resistant shield for use with a battery containment system that is light weight and resistant to corrosion, while improving the safety performance of the battery containment system by providing greater impact and impalement protection as compared to conventional vehicle components.
A puncture resistant shield is provided for use with a battery containment system of a vehicle. The puncture resistant shield includes a shield body portion configured to underlie the battery containment system, where the shield body portion has a first surface and an oppositely opposed second surface both bounded by a first end and a second end and a first side and a second side that each extend from the first end to the second end. A first ramp extends from the first end of the shield body portion at a first angle. The puncture resistant shield is configured to be attached to the battery containment system.
The present invention is further detailed with respect to the following drawings that are intended to show certain aspects of the present invention but should not be construed as a limit on the practice of the present invention.
The present invention has utility as a puncture resistant shield for use with a battery containment system that is light weight and resistant to corrosion, while improving the safety performance of the battery containment system by providing greater impact and impalement protection as compared to conventional vehicle components. The inventive puncture resistant shield also has utility in that it may be used with existing battery containment systems as an aftermarket installation to increase protection of the batteries contained therein or may be designed for use with new manufactured battery containment systems.
Battery cases and containment systems are getting bigger year by year due to the increase in amount of batteries installed. For example, the length of a typical battery case in a vehicle width direction is often 70% or more with respect to the vehicle width, and sometimes 80% or more. For this reason, when a large battery case is mounted in the lower part of the vehicle, a larger load is input to the battery case at the time of a collision rather than previous battery cases. Given the position and size of a battery case on vehicles, the batteries are susceptible to impalement from road or collision debris. Therefore, according to embodiments, the inventive penetration resistant shield is designed to be used with a battery containment case or system to provide resistance to such impalements in order to protect the batteries.
The present invention will now be described with reference to the following embodiments. As is apparent by these descriptions, this invention can be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. For example, features illustrated with respect to one embodiment can be incorporated into other embodiments, and features illustrated with respect to a particular embodiment may be deleted from the embodiment. In addition, numerous variations and additions to the embodiments suggested herein will be apparent to those skilled in the art in light of the instant disclosure, which do not depart from the instant invention. Hence, the following specification is intended to illustrate some particular embodiments of the invention, and not to exhaustively specify all permutations, combinations, and variations thereof.
It is to be understood that in instances where a range of values are provided that the range is intended to encompass not only the end point values of the range but also intermediate values of the range as explicitly being included within the range and varying by the last significant figure of the range. By way of example, a recited range of from 1 to 4 is intended to include 1-2, 1-3, 2-4, 3-4, and 1-4.
Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
Unless indicated otherwise, explicitly or by context, the following terms are used herein as set forth below. As used in the description of the invention and the appended claims, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Also as used herein, “and/or” refers to and encompasses any and all possible combinations of one or more of the associated listed items, as well as the lack of combinations when interpreted in the alternative (“or”).
Referring now to the figures, a puncture resistant shield 40 for use with a battery containment system 10 of a vehicle is shown. According to embodiments, the puncture resistant shield 40 includes a shield body portion 42 that has a first surface 44 and an oppositely opposed second surface 46 both bounded by a first end 48 and a second end 50 and a first side 52 and a second side 54 that each extend from the first end 48 to the second end 50. The puncture resistant shield 40 additionally includes a first ramp 56 extending from the first end 48 of the shield body portion 42 at a first angle α, which according to embodiments is an angle of 10 to 90 degrees. The puncture resistant shield 40 is configured to be attached to the battery containment system 10 such that the shield body portion 42 underlies the battery containment system 10.
As shown in the figures, a battery containment system 10 with which embodiments of the inventive puncture resistant shield 40 are used generally includes a tray 20 for containing a plurality of batteries 12 and a cover 30. Further details regarding features of a battery containment system 10 are described in co-pending International Patent Application No. PCT/US2020/031750, which is hereby incorporated by reference and are additionally described in part herein.
According to embodiments, the ramp 56 that extends from the first end 48 of the shield body portion 42 is integrally formed with the shield body portion 42. According to embodiments, the ramp 56 extends the entire length of the first end 48 of the shield body portion 42, and therefore the ramp 56 extends from the first end 48 of the shield body portion 42 from the first side 52 to the second side 54 of the shield body portion 42. According to embodiments, the puncture resistant shield 40 is configured to be attached to a battery containment system 10 such that first ramp 56 is positioned towards a front of the vehicle. According to embodiments, first ramp 56 is configured to be angled upwards towards said battery containment system 10 when said puncture resistant shield 40 is attached to the battery containment system 10. Such positioning and orientation of the first ramp 56 of the shield 40 allows the ramp 56 to further protect batteries 12 contained in the containment system 10 by deflecting road and crash debris that the vehicle may encounter when traveling in a forward direction. According to embodiments, the shield 40 additionally includes at least one additional ramp 56′ extending from at least one of the second end 50, the first side 52, and the second side 54 of the shield body portion 42 at a second angle β, which according to embodiments is the same angle as the first angle α.
According to certain inventive embodiments, the shield 40 is formed of reinforced sheet molding compound (SMC), a phenolic-SMC, epoxy, acrylonitrile butadiene styrene (ABS), polycarbonate, random-oriented fiber reinforced thermoplastic resin (FRTP), steel, or aluminum. Sheet molding compound (SMC) or sheet molding composite is a ready to mold fiber-reinforced polyester material primarily used in compression molding. SMC is a reinforced composite material that is manufactured by dispersing long strands (20-60 mm) of chopped glass fibers in a matrix of polyester resin. It is appreciated that fibers with long range order are also operative herein and include woven mats, continuous fibers, or sheet forms. Thermoplastic materials operative herein amenable to functioning as a fiber matrix illustratively include: poly(methyl methacrylate) (PMMA), acrylonitrile butadiene styrene (ABS), polyamides, polylactides, polybenzimidazoles, polycarbonates, polyether sulfones, polyethylene, polypropylene, polystyrene, polyvinyl chloride, or block copolymers of any one of the aforementioned constituting the majority by monomer number. Reinforcing fibers and fillers operative herein illustratively include carbon fibers, glass fibers, aramid fibers, cellulosic fibers, or a combination thereof. In some inventive embodiments, the chopped fiber is glass fiber, alone or in combination with other types of fiber or reinforcing fillers. According to embodiments, the shield 40 is formed of aramid fiber reinforced SMC, which is particularly well suited for resisting impalement by crash or road debris.
As shown in
According to embodiments, the shield 40 may have one or more coatings. The coating illustratively includes materials that impart fire resistance, are phenolic in nature, electromagnetic interference-radiofrequency interference (EMI-RFI) resistance, or a combination of such coatings. It is appreciated that coating as used in this context is intended to include separate layers of material that are applied as a sheet material to a substrate of the shield 40. That is, according to embodiments, the shield 40 is coated in a fire resistant, or a fire-retardant material. A fire-resistant material is one that is designed to resist burning and withstand heat and provide insulation to the substrate, while a fire-retardant material is designed to burn slowly and reduce the rate of flame spread. Intumescent fire-resistant materials work by expanding their volume from 15 to 30 times and generating an ash-like char layer that erodes as fire exposure continues. Expansion then occurs again with the number of times the process repeats itself dependent upon the thickness of the coating. For example, such fire resistant or fire retardant materials for coating the shield 40 include any of the following: silicone, casein or vinyl resins, aluminum trihydrate or antimony oxide, ammonium polyphosphate, pentaerythritol, melamine derivatives, boric acid (H3BO3) and borax (Na2B4O7.10H2O), disodium octaborate tetrahydrate (Na2B8O13.4H2O), dicyandiamide-formaldehyde-phosphoric acid, melamine-dicyandiamide-formaldehyde-phosphoric acid, poly(n-vinylpyrolidone), colloidal silica, magnesium hydroxide (MDH), monoammonium phosphate (MAP), aluminum hydroxide (ATH), carbonates and hydrogen carbonates, potassium carbonate, Na2WO4, Na2SnO3, Na2MoO4, ammonium polyphosphate, pentaerythritol, melamine, expandable graphite, or combinations thereof. Phenolic resins operative herein illustratively includes epoxy phenolic resins, and phenol formaldehyde resins that impart corrosion resistance and a mar resistance surface relative to the underlying substrate of the shield 40. EMI-RFI shielding coatings operative herein illustratively include nickel coated glass mat; carbon fiber matting; copper or nickel paint; various metal foils, such as aluminum, nickel, iron, copper, and alloys thereof; and or combinations thereof with the proviso that the EMI-RFI shielding is grounded so as to function as a Faraday cage. It is further appreciated that coatings in the form of sheets are readily applied as an underlying sheet below an inventive shield 40 or are included as filler in the materials that are used to form the shield 40.
According to embodiments, the puncture resistant shield 40 is configured to be attached to the battery containment system 10 using an adhesive 60 applied between the first surface 44 of the shield body portion 42 and a lower surface 22 of the battery containment system 10, which for example is the lower surface of the tray 20. According to embodiments, the puncture resistant shield 40 is configured to be attached to the battery containment system 10 by a plurality of fasteners 62, 62′ that extend through said shield body portion 42 through a plurality of through holes formed in said shield body portion 42. According to embodiments, such through holes may be formed in the material of the shield body portion 42 when the SMC material is laid up or may be formed subsequently by a drilling or stamping process. The plurality of fasteners 62 for example may include screws or bolts that are inserted through the shield body portion 42 such that the threaded end is secured within the battery containment system 10. Alternatively, the plurality of fasteners 62′ for example may include bolts that have their heads embedded in the battery containment system and their threads exposed downward for insertion through the holes 64 formed in the shield body portion 42. In such an instance, nuts 66 or other suitable securing devices are installed onto the threaded portions of the embedded bolts 62′ to secure the shield 40 to the battery containment system 10.
According to embodiments such as that shown in
As shown in
According to embodiments, the flange 32 of the cover and the shield flange 86 of the shield 40 are configured to engage one another in abutting contact such that the cover 30 and the shield 40 define a cavity 126 therebetween. The cavity 126 is configured to receive and contain the tray 20, as described above. The joiner clip 100 is configured to engage the cover flange 32 and the shield flange 86 to join the cover 30 and the shield 40 together.
According to embodiments, the cover flange 32 surrounds the perimeter of the cover 30. Similarly, according to embodiments, the shield flange 86 surrounds the perimeter of the shield 40. According to embodiments, such as those shown in
As shown in
According to embodiments, the free ends 136, 136′ of each of the jaws 134, 134′ are biased toward one another. Thus, when the joiner clip 100 is engaged with the flanges 32, 86, such that the flanges 32, 86 are positioned between the jaws 134, 134′ of the joiner clip 100, the joiner clip applies a compressive force to the cover flange 32 and the shield flange 86 to join the cover 30 and the shield 40 together. According to embodiments, the joiner clip is formed of a metal, such as spring steel, a thermoplastic, or an elastomeric material. Embodiments in which the joiner clip is formed of an elastomeric material provide the additional benefit of sealing the cover 30 and shield 40 while also joining them together. According to embodiments, the joiner clip 100 also includes at least on barb 138 positioned on an inner surface of at least one of the jaws 134, 134′. The barb or barbs 138 are configured to dig into the composite material of the flanges 32, 86 or may engage with a groove 140 formed in the flanges to prevent the joiner clip 100 from falling off of or being easily removed from the flanges 32, 86.
According to embodiments, the shield 40 also includes a barrier material 128 positioned between the cover flange 32 and the shield flange 86. According to embodiments, the barrier material 128 acts as a seal and/or a connector between the cover 30 and the shield 40 to limit movement or slippage between the cover 30 and the shield 40. According to embodiments, the barrier material 128 is any of an adhesive, a gasket, or a connector. In some embodiments, such as that shown in
Patent documents and publications mentioned in the specification are indicative of the levels of those skilled in the art to which the invention pertains. These documents and publications are incorporated herein by reference to the same extent as if each individual document or publication was specifically and individually incorporated herein by reference.
The foregoing description is illustrative of particular embodiments of the invention but is not meant to be a limitation upon the practice thereof. The following claims, including all equivalents thereof, are intended to define the scope of the invention.
This application claims priority benefit of U.S. Provisional Application Ser. No. 63/047,945 filed 3 Jul. 2020, the contents of which are hereby incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| 63047945 | Jul 2020 | US |
