Protection of electrical components in battery systems

Abstract

The present disclosure relates to materials and systems for managing thermal runaway issues in energy storage systems. Exemplary embodiments include insulated electrical connection elements that are protected from heat, gas, and / or particulate matter.

Description

[Technical field]

[0001] Claiming priority This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 338,331, filed May 4, 2022, which is incorporated by reference herein in its entirety.

[0002] The present disclosure relates generally to materials, systems, and methods for the protection of electrical connections. In particular, the present disclosure relates to materials, systems, and methods for the sealing of electrical connections (e.g., bus bars) using aerogel materials. The present disclosure further relates to battery modules or battery packs having one or more battery cells with sealed electrical connections, and systems including those battery modules or battery packs. [Background technology]

[0003] Rechargeable batteries, such as lithium-ion batteries, have found widespread applications in power drives and energy storage systems. Lithium-ion batteries (LIBs) are widely used to power portable electronic devices, such as mobile phones, tablets, laptops, power tools, and other high-current devices, such as electric vehicles, due to their high operating voltage, low memory effect, and high energy density compared to conventional batteries. However, safety is a concern for LIBs, as they are prone to catastrophic failure under "abuse conditions," such as when rechargeable batteries are overcharged (charged beyond their design voltage), overdischarged, or operated at or exposed to high temperatures and pressures. As a result, narrow operating temperature ranges and charge / discharge rates are limitations to the use of LIBs, as they can fail due to rapid self-heating or thermal runaway events when exposed to conditions outside their design window.

[0004] Thermal runaway can occur when the internal reaction rate increases to the point where more heat is generated than can be recovered, leading to further increases in both reaction rate and heat generation. During thermal runaway, high temperatures trigger a chain of exothermic reactions within the battery, which causes the temperature of the battery to rise rapidly. Often, when thermal runaway occurs in one battery cell, the generated heat rapidly heats cells adjacent to the cell that experienced thermal runaway. Each cell that adds to the thermal runaway reaction contains more energy to continue the reaction, which causes thermal runaway propagation within the battery pack and ultimately leads to a catastrophe involving fire or explosion. Rapid heat dissipation and effective blocking of the heat transfer path can be an effective countermeasure to reduce the danger caused by thermal runaway propagation.

[0005] Based on the understanding of the mechanisms that lead to thermal runaway in batteries, many approaches are being investigated with the aim of reducing safety hazards through rational design of battery components.

[0006] A typical battery system includes one or more battery modules, each of which includes multiple battery cells. A subset of the battery cells are electrically connected in parallel, and a subset are electrically connected in series by a series of current collectors (or bus bars). For example, the terminal current collectors, or bus bars, exhibit a potential difference that defines a DC bus. Switching components, fuse components, a bus bar carrying the highest voltage of the battery module, any other suitable power electronics, any other suitable components, or any combination thereof, may be located on or near the battery module(s). The bus bars are typically located on the sides (e.g., front, back, top, bottom, or any side) of the battery system to make suitable electrical connections between the components. The bus bars tend to extend over a portion of the battery module, and thus may be located over one or more battery cells (e.g., the vent end of the battery cells). When a battery cell experiences a thermal event, adjacent structures such as the bus bars may be damaged. Therefore, it may be desirable to provide protection from heat, gas, and / or particulate matter. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 illustrates a top view of a battery system, according to some exemplary embodiments. [Diagram 2] FIG. 2 illustrates a busbar, according to some example embodiments. [Diagram 3] FIG. 3 illustrates a cross-sectional view of a busbar, according to some example embodiments. [Figure 4] FIG. 4 shows an isometric view of a battery system, according to some illustrative embodiments. [Diagram 5] FIG. 5 illustrates a busbar assembly according to some example embodiments. [Figure 6] FIG. 6 illustrates a cross-sectional view of a busbar assembly according to some example embodiments. [Figure 7] FIG. 7 illustrates another busbar assembly, according to some example embodiments. [Figure 8] FIG. 8 illustrates another busbar assembly, according to some example embodiments. [Figure 9] FIG. 9 illustrates a battery system, according to some exemplary embodiments. [Figure 10] FIG. 10 illustrates another battery system, according to some exemplary embodiments. [Figure 11] FIG. 11 illustrates another battery system, according to some exemplary embodiments. [Figure 12] FIG. 12 illustrates another battery system, according to some exemplary embodiments. [Figure 13] FIG. 13 illustrates another battery system, according to some exemplary embodiments. [Figure 14] FIG. 14 illustrates another battery system, according to some exemplary embodiments. [Figure 15] FIG. 15 illustrates another battery system, according to some exemplary embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings which form a part hereof, and which show by way of illustration specific embodiments in which the disclosure may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the disclosure.

[0009] The present disclosure is directed to protecting electrical connection systems in energy storage systems. Exemplary embodiments include protecting bus bars in electrical storage systems through the use of aerogel materials.

[0010] 1 shows a schematic diagram of a typical electrical energy storage system 100 including a housing 104, battery modules 108A, 108B, 108C (collectively 108), and one or more bus bars 112. As described above, the energy storage system 100 may store and release electrical power for use in an electric vehicle or other electrically powered system.

[0011] In the electrical energy storage system 100, battery modules 108 are disposed within the housing 104. The battery modules 108 may include multiple individual cells 116 that may be electrically coupled. In one example, the cells 116 include lithium ion cells, although the disclosure is not so limited. One or more bus bars 112 of the system 100 electrically connect one or more of the battery modules 108. In some embodiments, the bus bars 112 may be elongated, conductive connectors that connect terminals from different battery modules or battery cells.

[0012] FIG. 2 illustrates a detailed view of one embodiment of a busbar 200, which includes conductors 204 and plugs 208A, 208B (collectively 208). The conductors 204 may be conductive elongated structures configured to span one or more battery modules and / or battery cells to connect corresponding terminals together. In the busbar 200 illustrated in FIG. 2, the conductors 204 are metal bars. Other implementations of the busbar 200 may have conductors 204 of different configurations, such as metal wires, conductive traces on a structural support, among others. Regardless of its configuration, the conductors 204 serve as the conductive portion of the busbar 200. In some examples, the conductors 204 of the busbar 200 may be constructed from a conductive metal, such as copper, aluminum, or a metal alloy.

[0013] The busbar 200 also includes plugs 208A, 208B connected to the conductors 204. The plugs 208A, 208B connect the busbar 200 to terminals (not shown in FIG. 2) of a battery module or battery cell. In one embodiment, the plugs 208A, 208B are configured to engage corresponding features on a module or cell in an energy storage system. One example of a corresponding feature for engaging the plugs 208A, 208B includes a slot on the module or cell. Examples of suitable materials for the busbar 200 include conductive metallic materials such as copper, aluminum, iron, or alloys thereof.

[0014] Figure 3 illustrates a cross-sectional view of the conductor 204 of the busbar 200 shown in Figure 2. As illustrated, the conductor 204 includes a conductive core 304, an insulating layer 308, and an encapsulation layer 312. The insulating layer 308 and the encapsulation layer 312, collectively referred to as a protective barrier 314, provide aspects of electrical, thermal, and mechanical protection to the conductor 204, thereby improving the overall resilience and durability of the busbar 200 in response to corresponding electrical, thermal, and / or mechanical stresses / perturbations. The materials of the conductive core 304 correspond to those already described above in the context of the conductor 204 shown in Figure 2.

[0015] 2 and 3, the protective barrier 314 at least partially covers the conductive core 304. In some embodiments, the protective barrier 314 may cover some or all of any subset of the length, width, and / or surface of the conductive core 304.

[0016] In some embodiments, the protective barrier 314 includes at least one insulating layer 308 and at least one encapsulation layer 312. As shown in FIG. 3, at least one of the insulating layers 308 is disposed between the conductive core 304 and the (outermost) encapsulation layer 312. It should be understood that different configurations of the protective barrier 314 having a greater number of one or more insulating layers 308 and / or encapsulation layers 312 are possible without departing from the concepts described herein. Additionally, different arrangements of layers may also be used to fabricate other embodiments of the protective barrier 314 without departing from the concepts described herein. Although not explicitly shown, the encapsulation layer 314 may surround at least a portion of the plug 208 (shown in FIG. 2) and some or all of the conductive core 304.

[0017] In some embodiments, the protective barrier 314 may include an aerogel material as a component within the insulating layer 308 and an encapsulation layer 312 that at least partially surrounds the insulating layer.

[0018] The insulating layer 308 may include any type of insulating layer commonly used to separate battery cells or battery modules that provides thermal insulation, electrical insulation, or both. In some embodiments, the insulating layer(s) 308 may include any one or more of a polymer-based thermal barrier (e.g., polypropylene, polyester, polyimide, and aromatic polyamide (aramid)), a phase change material, a thermal expansion material, an aerogel material, a mineral-based barrier (e.g., mica), and an inorganic thermal barrier (e.g., fiberglass-containing barrier), or a combination thereof. For example, an exemplary insulating layer may include a combination of a material, such as an aerogel material or composition, with another material, such as a mineral-based material (e.g., mica), a phase change material, or a thermal expansion material. In such examples, the aerogel material may incorporate other materials into the aerogel composition or structure. Alternatively, the aerogel material may be disposed adjacent to a layer of another material, such as a layer of aerogel composition adjacent to a layer of a mineral-based material (e.g., mica), a layer of a phase change material, or a layer of a thermal expansion material. In further embodiments, the aerogel material may be disposed between layers of a mineral-based material (eg, mica), a layer of a phase change material, or a layer of a thermally expansive material.

[0019] The insulating layer 308 may have a thermal conductivity through its thickness dimension of about 50 mW / mK or less, about 40 mW / mK or less, about 30 mW / mK or less, about 25 mW / mK or less, about 20 mW / mK or less, about 18 mW / mK or less, about 16 mW / mK or less, about 14 mW / mK or less, about 12 mW / mK or less, about 10 mW / mK or less, about 5 mW / mK or less, or a range between any two of these values, individually at 25° C. and atmospheric pressure and a mechanical load of up to about 5 MPa.

[0020] In some embodiments, the insulating layer 308 comprises an aerogel further comprising a reinforcing material. In some embodiments, the reinforcing material is a fiber selected from organic polymeric fibers, inorganic fibers, carbon-based fibers, or combinations thereof. In some embodiments, the fiber is in the form of discrete fibers, woven materials, dry-laid nonwoven materials, wet-laid nonwoven materials, needled nonwovens, batting, woven fabrics, mats, felts, and / or combinations thereof. In some embodiments, the inorganic fibers are selected from glass fibers, rock fibers, metal fibers, boron fibers, ceramic fibers, basalt fibers, or combinations thereof. In some embodiments, the reinforcing material is a foam selected from siloxanes, polyolefins, polyurethanes, phenolics, melamine, cellulose acetate, polyacrylonitrile oxide, and polystyrene. In some embodiments, the reinforcing material is selected from polymeric materials. Non-limiting examples of polymeric materials are resin, rubber, acrylic (PMMA), acrylonitrile butadiene styrene (ABS), nylon (polyamide, PA), polycarbonate (PC), polyethylene (PE), polyoxymethylene (POM), polypropylene (PP), polystyrene (PS), thermoplastic elastomer (TPE), thermoplastic polyurethane (TPU).

[0021] In one or more embodiments, the aerogel of the insulating layer 308 comprises a silica-based aerogel and / or an alumina silicate aerogel. In one or more embodiments, the aerogel of the insulating layer 308 comprises one or more additives, the additives being present at a level of at least about 5-40% by weight of the aerogel, preferably at a level of at least about 5-20% by weight of the aerogel, and more preferably at a level of at least about 10-20% by weight of the aerogel. In some embodiments, the one or more additives comprise a refractory class additive. In some embodiments, the one or more additives are selected from the group consisting of B4C, diatomaceous earth, manganese ferrite, MnO, NiO, SnO, Ag, and the like. 2 O, Bi 2 O 3In some embodiments, the one or more additives include an opacifying agent selected from TiC, WC, carbon black, titanium dioxide, iron titanium dioxide, zirconium silicate, zirconium oxide, iron (I) oxide, iron (III) oxide, manganese dioxide, iron titanium dioxide (ilmenite), chromium oxide, or mixtures thereof. In some embodiments, the one or more additives include an opacifying agent comprising silicon carbide. In some embodiments, the one or more additives include a combination of a fire-resistant class additive and an opacifying agent. In one or more embodiments, the aerogel has a density in the range of about 0.25 g / cc to about 1.0 g / cc. In some embodiments, the aerogel has a flexural modulus of about 2 MPa to about 8 MPa. In some embodiments, the aerogel has a compression set in the range of about 10% to about 25% at about 70° C. In some embodiments, the aerogel exhibits a compression resistance at 25% strain of between about 40 kPa to about 180 kPa. In one or more embodiments, the aerogel is in the form of a monolith, beads, particles, granules, powder, thin film, sheet, plaque, curved plaque, or combinations thereof.

[0022] In some embodiments, the sealing layer 312 of the protective barrier 314 may be made from a material that may protect the busbar from the external environment. For example, particulates and fluids (e.g., cooling fluids and electrolytes for batteries) may be present within the housing of the electrical energy storage system that, in the absence of the sealing layer 312, may degrade the electrical and / or thermal performance of the insulating layer 308 and / or conductive core 304. Additionally, it is preferred that the sealing layer be electrically insulating. This feature may help prevent shorting of the electrical system through the busbar.

[0023] In some embodiments, the sealing layer 312 may be made from a polymer selected from the group consisting of polyoxymethylene, acrylonitrile butadiene styrene, polyamideimide, polyamide, polycarbonate, polyester, polyetherimide, polystyrene, polysulfone, polyimide, and terephthalate.

[0024] Although the encapsulation layer 312 and the insulating layer 308 may combine to protect the busbar from damage resulting from elevated temperatures associated with thermal runaway of the battery cells, some implementations of the encapsulation layer 312 and / or the insulating layer 308 may not protect the conductive core 304 from physical impact of particulate matter from a ruptured battery cell. To improve the ability of the encapsulation layer 312 to resist mechanical damage from impacting particulates, the encapsulation layer 312 may be comprised of a hardened polymeric material. In some implementations, the hardened polymeric material may include a polymeric layer filled with a second phase known to add improved mechanical properties, thermal properties, and abrasion resistance. In one embodiment, the hardened second phase is particles of a ceramic material (e.g., silica nano / micro particles, silicate / clay nano / micro particles). In another embodiment, the hardened second phase is a barrier layer (not shown) incorporated into the polymeric material. The barrier layer may be made of a hard material that inhibits damage from particulate matter impacting the busbar at high speeds. Exemplary materials that may be used for the barrier layer include, but are not limited to, metal foil, mica, microporous silica, ceramic fibers, mineral wool, metals, carbon, conductive polymers, or combinations thereof.

[0025] In addition to the bus bars, the combination of insulating layer 308 and encapsulating layer 312 may also be used to protect other components within the battery pack, such as electrical devices and wiring, cooling tubes, battery cell or pack terminals, temperature sensors, connectors, and / or other components that are vulnerable during thermal runaway.

[0026] FIG. 4 illustrates an embodiment of an electrical energy storage system 400. In this embodiment, the electrical energy storage system 400 includes a plurality of battery cells 404. Each battery cell 404 has two terminals 408, a positive terminal and a negative terminal. In an embodiment, the battery cells 404 are connected in series with the positive or negative terminals 408 of adjacent battery cells 404 coupled together by a bus bar 412. The embodiment of the bus bar 412 illustrated in FIG. 4 may include any combination and / or subset of combinations of the features described above in the context of FIGS. 1, 2, and 3, or any features described elsewhere herein.

[0027] In some embodiments, including the embodiment shown in FIG. 4, the electrical energy storage system 400 may further include a busbar protection assembly 416. The busbar protection assembly 416 may be used to encapsulate one or more busbars. In some embodiments, one of which is shown in FIG. 6, the busbar protection assembly 416 includes a housing 604 having an interior space 606 defined by an inner surface 609 of the housing 604. The busbar protection assembly 416 may also include an insulating layer 608.

[0028] The housing 604 of the bus bar protection assembly 416 is configured and dimensioned such that the housing 609 is positionable over one or more bus bars 412, as shown in Figures 4 and 5. When positioned over the bus bars 412, the bus bars 412 are substantially encapsulated by the housing 604.

[0029] In an embodiment, the insulating layer 608 may include an aerogel material. The insulating layer 608 may conform to some or all of the inner surface of the housing 609, as shown in FIG. 6. For example, as shown in FIG. 6, the insulating layer 608 is located between one or more bus bars 412 and the inner surface 609 of the housing 604. In an embodiment, the insulating layer 608 covers at least a portion of the inner surface 609 of the housing 604.

[0030] In some embodiments, the insulating layer 608 may be made from a resilient material, alone or in combination with an aerogel material. The resilient insulating layer 608 may be compressed by the terminals 408 and by conforming the insulating layer to the shape of the terminals 408. Thus, in some embodiments, the insulating layer 608 has a thickness that allows the terminals 408 to fit within the interior space 606 of the housing 604 upon compression of the insulating layer 608. In alternative embodiments, the insulating layer 608 has a thickness that allows the battery cell terminals 408 to fit within the interior space 606 of the housing 604 without compressing the insulating layer 608.

[0031] The busbar protection assembly may be configured (having a shape and size) that allows the assembly to cover a single busbar or multiple busbars. In some embodiments, the busbar protection assembly covers all of the busbars on a surface of the battery module or battery pack.

[0032] In some embodiments, the busbar protection assembly covers the entire surface of the battery module or battery pack where the busbars are located (e.g., the top surface where the busbars are attached). When the busbar protection assembly covers the entire surface of the module / pack, the busbar protection assembly provides a cushion for the module / pack against potential mechanical shocks in addition to heat, fire, and electrical insulation functions. In this embodiment, the busbar protection assembly is slightly larger than the surface of the battery module / pack it covers, such that the surface of the module / pack with the busbars extends into the busbar protection assembly such that the busbar protection assembly surrounds a portion of the battery module / pack. The aerogel lining provides additional cushioning for the module / pack.

[0033] In some embodiments, busbars 700 and 800 may have a laminated structure, as shown in Figures 7 and 8. In the embodiment of busbar 700 shown in Figure 7, laminated busbar 700 includes one or more insulating layers 704A, 704B and one or more conductive layers 708. The one or more insulating layers preferably include an aerogel material.

[0034] The conductive layer includes two or more contacts 712A, 712B (collectively 712) that extend outwardly from the laminate structure and serve as connection areas for connecting the bus bars to terminals of adjacent battery cells or battery modules.

[0035] In the embodiment shown in FIG. 7, the insulating layers are disposed as outer layers in a laminate structure in which one or more conductive layers are sandwiched between the insulating layers.

[0036] 8, the laminated busbar 800 includes the elements discussed above in the context that the laminated busbar 800 (insulating layers 804A, 804B, conductive layer 808) may also include a barrier layer 816. The barrier layer is located under the laminated structure as shown and protects the conductive layers from damage caused by particulate matter expelled from the battery cells. Although shown as being only on the "bottom" side of the laminated structure, it should be understood that the barrier layer may be on the "top" side of the laminated structure (opposite the battery cells or battery modules) or on both sides of the laminated structure.

[0037] In the embodiment shown in FIG. 9, the bus bar system 900 includes one or more bus bars 912 that connect terminals of adjacent battery cells 902 or battery modules. A first insulating layer 904A is disposed over at least a portion of the battery cells 902 or battery modules. The first insulating layer 904A includes a plurality of openings. The openings in the first insulating layer are substantially aligned with the terminals 908 of the battery 902 such that the terminals 908 of the battery extend through the first insulating layer 904A and contact the one or more bus bars 912. In this embodiment, the first insulating layer 904A protects the bus bars 912 from heat resulting from a thermal runaway event without the need to modify commercially available bus bars.

[0038] To further protect the bus bars, a second insulating layer 904B may be located over the one or more bus bars 912. The first insulating layer 904A may be connected to the second insulating layer 904B such that the one or more bus bars 912 are substantially surrounded by the first insulating layer 904A and the second insulating layer 904B. In an embodiment, the one or more bus bars 912 contact and compress the second insulating layer 904B such that the compressed second insulating layer 904B substantially surrounds the one or more bus bars 912.

[0039] In an embodiment, the first insulating layer 904A and / or the second insulating layer 904B include one or more additional openings aligned with one or more vents present in the battery cell or battery module. The openings aligned with the vents are typically aligned over vents that are not directly under or near the busbar 912. In the case of vents located under one or more busbars 912, it is preferable to have a portion of the insulating layer covering the vent such that the insulating layer is located between the vent and the busbar.

[0040] In an embodiment, the first insulating layer 904A includes a thermally conductive element coupled to a cooling element. In an embodiment, the thermally conductive element is disposed between the first insulating layer 904A and the battery cell 902. In an embodiment, the thermally conductive element is disposed between the first insulating layer and the second insulating layer. In an embodiment, the thermally conductive element is in direct contact with the bus bar.

[0041] In the embodiment shown in FIG. 10, a U-shaped busbar 1012 is configured to electrically connect battery cells 1002 or battery modules. The U-shaped busbar 1012 includes a first conductive U-shaped portion 1012A, a second conductive U-shaped portion 1012B, and two channels 1013 that receive electrode tabs 1008 from adjacent battery cells 1002. During assembly, the second conductive U-shaped portion 1012B fits into the first conductive U-shaped portion 1012A to secure the electrode tabs 1008 in the two channels 1013. The insulating material 1004 is in contact with the first U-shaped portion 1012A and / or the second U-shaped portion 1012B. The insulating material helps protect the U-shaped busbar.

[0042] In an embodiment, the insulating material 1004 is located on the U-shaped busbar 1012. The insulating material may include a first insulating material 1004A disposed within an interior space defined by the first U-shaped busbar 1012A and a second insulating material 1004B contacting an outer surface of the second U-shaped busbar 1012B. The second insulating material 1004B extends downward to separate adjacent battery cells or battery modules. In an embodiment, the first insulating material 1004A includes a corrugated structure, the corrugated structure being located on the multiple U-shaped busbars. The insulating material in this embodiment is made of the same material used to form the insulating layer, as described herein.

[0043] An alternative embodiment is shown in Figure 11. In this embodiment, the insulating material 1104 located on the inside of the busbar 1112 extends outward from the busbar 1112 to act as isolation material between adjacent battery cells 1102.

[0044] In the embodiment shown in FIG. 12, the battery module 1200 includes a housing 1202 and a housing lid 1204 for enclosing two or more battery cells 1210. The two or more battery cells 1210 are electronically connected by a bus bar 1212. The bus bar is substantially surrounded by a first insulating layer 1206 and a second insulating layer 1208. The battery module further includes a top cover 1220 adjacent to the second insulating layer 1208. The top cover 1220 protects the housing lid 1204 from damage caused by, for example, particulate matter expelled from the battery cells 1210 during thermal runaway, thereby containing the thermal runaway within the housing 1202 and the lid 1204. In a non-limiting embodiment, the top cover 1220 is located between the second insulating layer 1208 and the housing lid 1204. In some embodiments, the top cover 1220 includes one layer having a uniform composition. In some embodiments, the top cover 1220 comprises an aerogel composition.

[0045] In the embodiment shown in FIG. 13, the battery module 1300 includes a housing 1302 and a housing lid 1304 for enclosing two or more battery cells 1310. The top cover 1320 includes an insulating layer 1322 as described with respect to FIGS. 7-11 and a rigid layer 1324 having a higher rigidity than the insulating layer 1322. In some embodiments, the insulating layer 1322 prevents heat transfer through the housing lid 1304. For example, the insulating layer 1322 prevents heat transfer to the housing lid 1304 and components (e.g., chassis) that may be on the battery module 1300. In another example, the insulating layer 1322 prevents heat loss from the battery module 1300 to a cold weather environment. In a non-limiting embodiment, the rigid layer 1324 is disposed between the insulating layer 1322 and the battery cells 1310 to protect the insulating layer 1322 from particulate matter that may be expelled from the battery cells 1310 during thermal runaway.

[0046] In an alternative embodiment shown in FIG. 14, a battery module 1400 includes a housing 1402 and a housing lid 1404 for enclosing two or more battery cells 1410. A top cover 1420 includes two rigid layers 1422, 1426 and an insulating layer 1424 disposed therebetween. The additional rigid layer 1422 between the insulating layer 1424 and the housing lid 1404 provides better protection than a single rigid layer with respect to any particulate matter that may be expelled from the battery cells 1410 during thermal runaway. In some embodiments, the top cover 1420 may include two or more insulating layers 1424 and rigid layers 1422, 1426. In some embodiments, the rigid layers 1422, 1426 may include the same material as the barrier layers shown in FIG. 8.

[0047] In some embodiments, the one or more rigid layers 1422, 1426 may be selected from aerogel (e.g., a monolithic aerogel plate), metal foil, mica, microporous silica, ceramic fiber, fiberglass, mineral wool, metal, carbon, conductive polymers, acrylate polymers, polycarbonate, polyester, styrene, vinyl PVC, cellulose acetate, nylon, phenolics, or combinations thereof.

[0048] In the embodiment shown in FIG. 15, the battery pack 1500 includes multiple battery modules 1510, similar to the modules described in FIG. 12, except that the second insulating layer 1508 extends over more than one battery module 1510. In an alternative embodiment (not shown), each battery module 1510 has a separate second insulating layer 1508. The battery pack 1500 may also include a bus bar 1512 disposed between the first insulating layer 1506 and the second insulating layer 1508 to electrically connect the battery modules 1510. The battery pack 1500 may also include a secondary bus bar 1514 disposed between the first insulating layer 1506 and the second insulating layer 1508 to laterally electrically connect the battery modules 1510. The embodiment of FIG. 15 may also include a top cover 1520, as described above in connection with the embodiments of FIGS. 12-14. The top cover 1520 may separately cover each individual battery module 1510. Alternatively, the top cover 1520 may extend over more than one battery module, as shown in FIG.

[0049] As noted above, embodiments of the first insulating layer, the second insulating layer, and the top cover can include one or more layers of an aerogel composition. Other insulating materials besides aerogel are within the scope of this disclosure.

[0050] Using an isolation barrier within a battery module or pack The insulated electrical connectors (e.g., bus bars) disclosed herein are useful for electrically connecting battery cells or battery components of any configuration of battery, such as pouch cells, cylindrical cells, prismatic cells, etc., and packs and modules incorporating or including any such cells. The electrical connectors disclosed herein are useful in rechargeable batteries, such as lithium ion batteries, solid state batteries, and any other energy storage device or technology.

[0051] Passive devices such as cooling systems may be used in conjunction with the insulating connectors of the present disclosure in a battery module or battery pack.

[0052] The insulated electrical connectors according to various embodiments of the present disclosure may be used in a battery pack including multiple battery modules or a battery module having multiple battery cells. A battery module is composed of multiple battery cells arranged in a single housing. A battery pack is composed of multiple battery modules.

[0053] The battery modules and battery packs can be used to supply electrical energy to devices or vehicles. Devices that use the battery modules or battery packs include, but are not limited to, laptop computers, PDAs, cell phones, tag scanners, audio devices, video devices, display panels, video cameras, digital cameras, desktop computers, military portable computers, military telephones, laser range finders, digital communication devices, intelligence gathering sensors, electronic integrated apparel, night vision equipment, power tools, calculators, radios, remote control devices, GPS devices, handheld and portable televisions, automobile starters, flashlights, sound devices, portable heating devices, portable vacuum cleaners, or portable medical instruments. When used in vehicles, the battery packs can be used in all-electric vehicles or hybrid vehicles.

[0054] To better illustrate the methods and apparatus disclosed herein, a non-limiting list of embodiments is now provided.

[0055] Example 1 is a busbar configured to electrically connect battery cells or battery modules including a protective barrier that at least partially encapsulates the busbar, the busbar comprising elongated conductive portions and plugs on opposing ends of the elongated conductive portions, the protective barrier including at least one insulating layer and optionally a sealing layer at least partially surrounding the insulating layer, the insulating layer being located between the busbar and the optional sealing layer.

[0056] Example 2 includes the busbar of example 1, where the protective barrier completely surrounds the elongated conductive portions.

[0057] Example 3 includes the busbar of any one of Examples 1-2, wherein the protective barrier surrounds at least a portion of the plug.

[0058] Example 4 includes the busbar of any one of Examples 1-3, wherein the insulating layer covers one side of the elongated conductive portions and the encapsulating layer completely surrounds the elongated conductive portions.

[0059] Example 5 includes the busbar of any one of Examples 1-4, wherein the insulation layer has a thermal conductivity through a thickness dimension of the insulation layer of less than about 50 mW / m·K at 25° C. and less than about 60 mW / m·K at 600° C.

[0060] Example 6 includes the bus bar of any one of Examples 1-5, wherein the insulating layer includes an aerogel material.

[0061] Example 7 includes the busbar of any one of Examples 1-6, wherein the insulating layer further includes a thermal expansion material.

[0062] Example 8 includes the busbar of any one of Examples 1-7, wherein the insulating layer includes a reinforcing material.

[0063] Example 9 includes the busbar of any one of Examples 1-8, wherein the reinforcing material is a fiber selected from an organic polymer-based fiber, an inorganic fiber, a carbon-based fiber, or a combination thereof.

[0064] Example 10 includes the busbar of any one of Examples 1-9, wherein the fibers are in the form of discrete fibers, woven materials, dry-laid nonwoven materials, wet-laid nonwoven materials, needled nonwovens, batting, woven fabrics, mats, felts, and / or combinations thereof.

[0065] Example 11 includes the busbar of any one of Examples 1-10, wherein the inorganic fibers are selected from glass fibers, rock fibers, metal fibers, boron fibers, ceramic fibers, basalt fibers, or combinations thereof.

[0066] Example 12 includes the busbar of any one of Examples 1-11, wherein the reinforcing material is a foam selected from siloxane, polyolefin, polyurethane, phenolic, melamine, cellulose acetate, and polystyrene.

[0067] Example 13 includes the busbar of any one of Examples 1-12, wherein the sealing layer includes a polymeric material.

[0068] Example 14 includes the busbar of any one of Examples 1-13, wherein the encapsulation layer includes a polymeric material and a barrier layer embedded in the polymeric material.

[0069] Example 15 includes the busbar of any one of Examples 1-14, wherein the barrier layer includes a metal foil.

[0070] Example 16 includes the busbar of any one of Examples 1-15, wherein the barrier layer includes mica.

[0071] Example 17 includes the busbar of any one of Examples 1-16, wherein the barrier layer includes microporous silica, ceramic fiber, mineral wool, metal, carbon, a conductive polymer, aerogel powder, or a combination thereof.

[0072] Example 18 is a busbar protection assembly configured to at least partially encapsulate one or more busbars, the busbar protection assembly comprising: a housing having an interior space defined by an inner surface of the housing, the housing having a shape and size such that the housing is positionable over the one or more busbars, the one or more busbars being substantially encapsulated by the housing during use; and an insulating layer located inside the housing, the insulating layer being located between the one or more busbars and the inner surface of the housing.

[0073] Example 19 includes the bus bar of example 18, wherein the insulating layer covers at least a portion of the inner surface of the housing.

[0074] Example 20 includes the busbar of any one of Examples 18-19, wherein the insulating layer has a thickness that enables the battery cell terminal to fit within the interior space of the housing without compressing the insulating layer.

[0075] Example 21 includes the busbar of any one of Examples 18-20, wherein the insulating layer has a thickness that enables the battery cell terminal to fit within the interior space of the housing when the insulating layer is compressed.

[0076] Example 22 includes the bus bar of any one of Examples 18-21, wherein the bus bar protection assembly covers a single bus bar.

[0077] Example 23 includes the bus bar of any one of Examples 18-22, wherein the bus bar protection assembly covers a plurality of bus bars.

[0078] Example 24 includes the bus bar of any one of Examples 18-23, wherein the bus bar protection assembly covers all bus bars on a surface of the battery module or battery pack.

[0079] Example 25 includes the bus bar of any one of Examples 18-24, wherein the bus bar protection assembly covers an entire surface of the battery module or battery pack, the covered surface including one or more bus bars.

[0080] Example 26 includes the busbar of any one of Examples 18-25, wherein the insulating layer provides a buffer between the housing and a battery cell terminal or battery module terminal that extends into the housing during use.

[0081] Example 27 includes the bus bar of any one of Examples 18-26, wherein the insulating layer has a thermal conductivity through a thickness dimension of the insulating layer of less than about 50 mW / m·K at 25° C. and less than about 60 mW / m·K at 600° C.

[0082] Example 28 includes the bus bar of any one of Examples 18-27, wherein the insulating layer includes an aerogel material.

[0083] Example 29 includes the bus bar of any one of Examples 18-28, wherein the insulating layer further includes a thermal expansion material.

[0084] Example 30 includes the busbar of any one of Examples 18-29, wherein the encapsulation layer includes a polymeric material.

[0085] Example 31 includes the busbar of any one of Examples 18-30, wherein the encapsulation layer includes a polymeric material and a barrier layer embedded in the polymeric material.

[0086] Example 32 includes the busbar of any one of Examples 18-31, wherein the barrier layer includes a metal foil.

[0087] Example 33 includes the bus bar of any one of Examples 18-32, wherein the barrier layer includes mica.

[0088] Example 34 includes the busbar of any one of Examples 18-33, wherein the busbar is a laminated structure including one or more insulating layers and one or more conductive layers, the conductive layers including two or more contacts that connect battery cells or battery modules during use.

[0089] Example 35 includes the busbar of any one of Examples 18-34, wherein the insulating layer is disposed as an outer layer of the laminate structure and the one or more conductive layers are sandwiched between the insulating layers.

[0090] Example 36 includes the busbar of any one of Examples 18-35, wherein the laminate structure further includes a barrier layer coupled to the insulating layer.

[0091] Example 37 includes the busbar of any one of Examples 18 to 36, wherein the laminate structure includes, in order from one side of the laminate structure to the other, a barrier layer, a first insulating layer, a conductive layer, and a second insulating layer.

[0092] Example 38 includes the bus bar of any one of Examples 18-37, wherein the insulating layer has a thermal conductivity through a thickness dimension of the insulating layer that is less than about 50 mW / m·K at 25° C. and less than about 60 mW / m·K at 600° C.

[0093] Example 39 includes the bus bar of any one of Examples 18-38, wherein the insulating layer includes an aerogel material.

[0094] Example 40 includes the bus bar of any one of Examples 18-39, wherein the insulating layer further includes a thermal expansion material.

[0095] Example 41 includes the busbar of any one of Examples 18-40, wherein the sealing layer includes a polymeric material.

[0096] Example 42 includes the busbar of any one of Examples 18-41, wherein the encapsulation layer includes a polymeric material and a barrier layer embedded in the polymeric material.

[0097] Example 43 includes the busbar of any one of Examples 18-42, wherein the barrier layer includes a metal foil.

[0098] Example 44 includes the bus bar of any one of Examples 18-43, wherein the barrier layer includes mica.

[0099] Example 45 is a busbar system connecting multiple battery cells or battery modules, the busbar system including a first insulating layer positioned over at least a portion of the battery cells or battery modules, the first insulating layer including a plurality of openings and one or more bus bars electrically connecting the one or more battery cells or battery modules, the openings in the first insulating layer being aligned with the terminals of the battery such that the terminals of the battery extend through the first insulating layer and contact the one or more bus bars.

[0100] Example 46 includes the bus bar of example 45, further including a second insulating layer overlying the one or more bus bars.

[0101] Example 47 includes the busbar of any one of Examples 45-46, wherein the first insulating layer is connected to the second insulating layer such that the one or more busbars are substantially surrounded by the first insulating layer and the second insulating layer.

[0102] Example 48 includes the bus bar of any one of examples 45-47, wherein the one or more bus bars contact and compress the second insulating layer such that the compressed second insulating layer substantially surrounds the one or more bus bars.

[0103] Example 49 includes the busbar of any one of Examples 45-48, wherein the first insulating layer and / or the second insulating layer includes one or more additional openings aligned with one or more vent holes present in the battery cell or battery module.

[0104] Example 50 includes the busbar of any one of Examples 45-49, wherein the one or more vent holes are not under the one or more busbars.

[0105] Example 51 includes the bus bar of any one of Examples 45-50, wherein at least some of the one or more vent holes are located under the one or more bus bars, and when the vent holes are located under the one or more bus bars, the first insulating layer is located between the one or more vent holes.

[0106] Example 52 includes the busbar of any one of Examples 45-51, wherein the first insulating layer includes a thermally conductive element coupled to a cooling element.

[0107] Example 53 includes the bus bar of any one of Examples 45-52, wherein the first insulating layer and / or the second insulating layer includes an aerogel material.

[0108] Example 54 is a U-shaped busbar configured to electrically connect battery cells or battery modules, the busbar comprising a first conductive U-shaped portion, a second conductive U-shaped portion, two channels for receiving electrode tabs from adjacent battery cells, the second conductive U-shaped portion fitting within the first conductive U-shaped portion to secure the electrode tabs within the two channels, and an insulating material in contact with the first U-shaped portion and / or the second U-shaped portion.

[0109] Example 55 includes the U-shaped busbar of Example 54, with the insulating material located on top of the U-shaped busbar.

[0110] Example 56 includes the U-shaped busbar of any one of Examples 54-55, wherein the insulating material includes a first insulating material disposed within an interior space defined by the U-shaped busbar and a second insulating material contacting an outer surface of the U-shaped busbar.

[0111] Example 57 includes the U-shaped busbar of any one of Examples 54-56, where the second insulating material extends downwardly to separate adjacent battery cells or battery modules.

[0112] Example 58 includes the U-shaped busbar of any one of Examples 54-57, wherein the second insulating material extends downwardly through an opening in the bottom surface of the first conductive U-shaped portion.

[0113] Example 59 includes the U-shaped busbar of any one of Examples 54-58, wherein the first insulating material includes corrugated structures, the corrugated structures being located on a plurality of the U-shaped busbar.

[0114] Example 60 includes the U-shaped busbar of any one of Examples 54-59, wherein the insulating material includes aerogel.

[0115] Example 61 includes a battery module comprising a plurality of battery cells, a housing and a housing lid that accommodate the plurality of battery cells, and an insulating layer between the housing lid and the plurality of battery cells.

[0116] Example 62 includes the battery module of example 61, wherein the insulating layer includes an aerogel.

[0117] Example 63 includes the battery module of any one of Examples 61-62, further including a barrier layer between the plurality of battery cells and the housing lid.

[0118] Example 64 includes the battery module of any one of Examples 61-63, wherein the barrier layer is between the insulating layer and the housing lid.

[0119] Example 65 includes the battery module of any one of Examples 61-64, wherein the barrier layer is selected from a material selected from metal foil, mica, microporous silica, ceramic fiber, mineral wool, metal, carbon, a conductive polymer, or a combination thereof.

[0120] Example 66 includes the battery module of any one of Examples 61-65, further including one or more busbars or busbar systems according to any one of claims 1-60.

[0121] Example 67 includes the battery module of any one of Examples 61-66, wherein the top cover is configured to withstand damage from particulate matter expelled from the battery cells.

[0122] Example 68 includes the battery module of any one of Examples 61 to 67, wherein the top cover includes a hard layer and an insulating layer.

[0123] Example 69 includes the battery module of any one of Examples 61-68, wherein the top cover includes a metal foil or mica.

[0124] Example 70 is a power system including one or more battery modules described in Example 61.

[0125] Example 71 is a device or vehicle including a battery module according to example 70.

[0126] Example 72 includes the device of Example 71, wherein the device is a laptop computer, a PDA, a mobile phone, a tag scanner, an audio device, a video device, a display panel, a video camera, a digital camera, a desktop computer, a military portable computer, a military telephone, a laser range finder, a digital communication device, an intelligence gathering sensor, electronic integrated apparel, a night vision device, a power tool, a calculator, a radio, a remote control device, a GPS device, a handheld and portable television, an automobile starter, a flashlight, an acoustic device, a portable heating device, a portable vacuum cleaner, or a portable medical instrument.

[0127] Example 73 includes the device of example 71, wherein the vehicle is an electric vehicle.

[0128] The above description is intended to be illustrative rather than limiting. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. Other embodiments may be used by those of ordinary skill in the art who have reviewed the above description. The Abstract is provided to enable the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Also, in the above Detailed Description, various features may be grouped together to streamline the disclosure. This should not be construed as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed embodiment. Accordingly, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment, and it is contemplated that such embodiments can be combined with each other in various combinations or permutations. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

[0129] Although a summary of the inventive subject matter has been described in connection with certain exemplary embodiments, various modifications and changes can be made to those embodiments without departing from the broader scope of the disclosed embodiments. Such embodiments of the inventive subject matter may be referred to herein by the term "invention" either individually or collectively, merely for convenience, without any intention to intentionally limit the scope of this application to any single disclosure or inventive concept when in fact more than one is disclosed.

[0130] The embodiments described herein are described in sufficient detail to enable those skilled in the art to practice the disclosed teachings. Other embodiments may be used and derived therefrom, such that structural and logical substitutions and changes may be made without departing from the scope of the disclosure. The detailed description is therefore not to be taken in a limiting sense, and the scope of the various embodiments is defined solely by the appended claims, along with the full scope of equivalents to which such claims are entitled.

[0131] The term "or" as used herein may be interpreted in either an inclusive or exclusive sense. Furthermore, multiple instances may be provided as a single instance for resources, operations, or structures described herein. In addition, boundaries between various resources, operations, systems, engines, and data stores are somewhat arbitrary, with particular operations being illustrated in the context of specific example configurations. Other allocations of functionality are contemplated and may fall within the scope of various embodiments of the disclosure. In general, structures and functionality presented as separate resources in an example configuration may be implemented as a combined structure or resource. Similarly, structures and functionality presented as a single resource may be implemented as a separate resource. These and other variations, modifications, additions, and improvements fall within the scope of the embodiments of the disclosure as expressed by the appended claims. The specification and drawings are therefore to be regarded in an illustrative and not a restrictive sense.

[0132] The foregoing description has been set forth in terms of specific exemplary embodiments for purposes of illustration. However, the exemplary description above is not intended to be exhaustive or to limit possible exemplary embodiments to the precise forms disclosed. Many modifications and variations are possible in light of the above teachings. The exemplary embodiments have been chosen and described in order to best explain the principles involved and their practical application, thereby enabling those skilled in the art to best utilize various exemplary embodiments with various modifications as suited to the particular use contemplated.

[0133] It should also be understood that terms such as "first", "second", etc. may be used herein to describe various elements, but these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, a first contact may be called a second contact, and similarly, a second contact may be called a first contact, without departing from the scope of the present exemplary embodiment. Although a first contact and a second contact are both contacts, they are not the same contact.

[0134] The terminology used in the description of the exemplary embodiments herein is for the purpose of describing the particular exemplary embodiment only and is not intended to be limiting. As used in the description of the exemplary embodiments and the accompanying examples, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It is also to be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. It is further to be understood that the terms "comprises" and / or "comprising", as used herein, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0135] The term "if" as used herein may be interpreted to mean "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrase "when determined" or "when [a stated condition or event] is detected" may be interpreted to mean "upon determining" or "in response to determining" or "upon detecting [a stated condition or event]" or "in response to detecting [a stated condition or event]," depending on the context.

Claims

1. A battery module, a plurality of battery cells; a housing and a housing lid that accommodate the plurality of battery cells; a laminated bus bar including an insulating layer between the housing lid and the plurality of battery cells; Equipped with The insulating layer comprises an aerogel. The battery module.

2. The battery module of claim 1 , further comprising a barrier layer between the plurality of battery cells and the housing lid.

3. The battery module of claim 2 , wherein the barrier layer is between the insulating layer and the housing lid.

4. 3. The battery module of claim 2, wherein the barrier layer is selected from a material selected from metal foil, mica, microporous silica, ceramic fiber, mineral wool, metal, carbon, conductive polymer, or a combination thereof.

5. The battery module of claim 1 , wherein the insulating layer includes a plurality of openings, the plurality of battery cells include a plurality of terminals, the plurality of terminals extending through the plurality of openings.

6. The battery module of claim 1 , wherein the insulating layer includes a plurality of openings, the plurality of battery cells include a plurality of vent holes, the openings aligned with the plurality of vent holes.

7. The battery module according to claim 1 , wherein the plurality of battery cells include a plurality of vent holes, and the insulating layer is located between the plurality of vent holes and the bus bar.

8. 8. The battery module of claim 7, wherein the insulating layer includes a plurality of openings aligned with the plurality of vent holes, the plurality of vent holes not aligned with the bus bar.

9. The battery module of claim 1 , wherein the insulating layer is a first insulating layer, and the battery module further includes a second insulating layer between the housing lid and the plurality of battery cells.

10. 10. The battery module of claim 9, wherein the battery module further includes a laminated bus bar, the laminated bus bar including the first insulating layer, the second insulating layer, and a conductive layer between the first insulating layer and the second insulating layer.

11. 11. The battery module of claim 10, wherein the plurality of battery cells include a plurality of terminals, and the conductive layer extends from the first insulating layer and the second insulating layer to connect the bus bar and the plurality of terminals.

12. 11. The battery module of claim 10, wherein the conductive layer contacts and compresses the second insulating layer, the compressed second insulating layer surrounding the conductive layer.

13. 11. The battery module of claim 10, wherein the first insulating layer is connected to the second insulating layer, and the conductive layer is surrounded by the first insulating layer and the second insulating layer.

14. The battery module of claim 2 , wherein the barrier layer is between the insulating layer and the plurality of battery cells.

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