Battery assembly

Abstract

The invention discloses a battery assembly. In one embodiment, a battery assembly includes a housing, a plurality of cells housed in a first interior space of the housing, and a plurality of particulate insulating materials housed in a second interior space of the housing.

Description

Technical Field

[0001] The technologies and embodiments disclosed in this application document generally relate to secondary batteries, and more specifically, to battery assemblies. Background Art

[0002] A secondary battery is a battery that can be charged and discharged multiple times. A secondary battery can be composed of battery cells or battery assemblies (e.g., battery modules, battery packs, etc.), and each battery cell or battery assembly is composed of multiple battery cells. When heat or gas is generated in one battery cell within a battery assembly, it can affect adjacent battery cells, resulting in stability problems such as accelerated heat propagation. Therefore, technologies aimed at improving the stability of battery cells and battery assemblies are needed. Summary of the Invention

[0003] The technologies disclosed herein can be implemented in some embodiments to provide a battery assembly with improved stability.

[0004] The technologies disclosed herein can be applied to green technology fields such as solar power generation and wind power generation. In addition, the technologies disclosed herein can be directly or indirectly applied to environmental protection devices such as electric vehicles and hybrid vehicles to prevent air pollution and climate change by suppressing greenhouse gas emissions.

[0005] A battery assembly according to an embodiment of the technologies disclosed herein may include: a housing; a plurality of battery cells accommodated in a first internal space of the housing; and a plurality of particle-shaped insulating materials accommodated in a second internal space of the housing. In some embodiments of the technologies disclosed herein, the term "particle-shaped insulating material" may refer to a particulate insulating material.

[0006] In one embodiment, one of the plurality of particle-shaped insulating materials may have a hardness value that is greater than or equal to a first hardness value and less than or equal to a second hardness value, and the second hardness value is higher than the first hardness value. The first hardness value may be higher than the hardness value at which the particle-shaped insulating material is damaged due to vibration.

[0007] In one embodiment, the first hardness value may be Shore hardness A5.

[0008] In one embodiment, each of the plurality of battery cells may include an electrode assembly and an exterior material that houses the electrode assembly, and the second hardness value may be lower than the hardness of the exterior material.

[0009] In one embodiment, the second hardness value may be Shore hardness A95.

[0010] In one embodiment, each of the plurality of battery cells may include: an electrode assembly; a main body configured to accommodate the electrode assembly; and a tab protruding from the main body, wherein the battery assembly may further include a bus bar disposed between the main bodies of the plurality of battery cells and the housing and electrically connected to the tab, and wherein, among the plurality of particulate insulating materials, the filling ratio of the particulate insulating material disposed between the main bodies of the plurality of battery cells and the bus bar may be higher than the filling ratio of the particulate insulating material disposed between the bus bar and the housing.

[0011] In one embodiment, the withstand voltage corresponding to the diameter of at least one of the plurality of particulate insulating materials may be higher than or equal to the first withstand voltage.

[0012] In one embodiment, each of the plurality of battery cells may include: an electrode assembly; an outer material configured to accommodate the electrode assembly; and a tab protruding from the outer material, and the first withstand voltage may be higher than a value obtained by dividing an overvoltage applied to the tab by the diameter of at least one of the plurality of particulate insulating materials.

[0013] In one embodiment, the first withstand voltage may be 1 kV / mm.

[0014] In one embodiment, the withstand voltage of the at least one particulate insulating material may be 30 kV / mm or less.

[0015] In one embodiment, the cross-sectional shape of at least one of the plurality of particulate insulating materials may be at least one of circular, oval, polygonal, or amorphous.

[0016] In one embodiment, the at least one particulate insulating material may include a core and a coating portion covering the core.

[0017] In one embodiment, each of the core and the coating portion may include at least one of an inorganic material or a foam material.

[0018] In one embodiment, one of the core and the coating portion may include a material not included in the other.

[0019] In one embodiment, at least one of the plurality of particulate insulating materials may exhibit at least one property of heat insulation and flame retardancy.

[0020] In one embodiment, the diameter of at least one of the plurality of particulate insulating materials may be 1 mm or more and 15 mm or less.

[0021] In one embodiment, each of the plurality of battery cells may include an outer material configured to house the electrode assembly; and a tab protruding from the outer material, wherein one or more of the plurality of particulate insulating materials may be disposed between the tabs of the plurality of battery cells.

[0022] In one embodiment, the battery assembly further includes: an auxiliary member disposed in a third internal space adjacent to the plurality of battery cells, wherein the volume ratio of the total volume of the plurality of particulate insulating materials to the volume of the second internal space is 25% or more and 90% or less.

[0023] In one embodiment, the housing may include an upper housing disposed on the upper side of the plurality of battery cells, wherein one or more of the plurality of particulate insulating materials may be disposed between the plurality of battery cells and the upper housing.

[0024] In some embodiments, the techniques disclosed herein may be implemented to provide a battery assembly having improved stability.

[0025] In some embodiments, the techniques disclosed herein may be implemented to provide a battery assembly having improved heat insulation.

[0026] In some embodiments, the techniques disclosed herein may be implemented to provide a battery assembly having improved electrical insulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 An exploded diagram illustrating a battery assembly based on an embodiment is shown.

[0028] Figure 2 A schematic diagram of a battery assembly with the upper housing removed based on an embodiment is shown.

[0029] Figure 3 A schematic diagram of a battery assembly including a plurality of particulate insulating materials based on an embodiment is shown.

[0030] Figure 4 A schematic diagram of a battery assembly including a plurality of particulate insulating materials based on another embodiment is shown.

[0031] Figure 5 An enlarged view of a plurality of particulate insulating materials based on an embodiment is shown.

[0032] Figure 6A diagram showing an example shape of a particulate insulating material according to an embodiment. Detailed Description

[0033] The structural or functional descriptions of the embodiments disclosed in this application document are only for the purpose of illustration to explain the embodiments of the disclosed technology, and the embodiments of the disclosed technology can be implemented in various forms in addition to the embodiments disclosed in this application document. Furthermore, the technology disclosed herein is not to be construed as limited to the embodiments described in this application document.

[0034] Figure 1 A exploded view showing a battery assembly according to an embodiment is illustrated.

[0035] Figure 2 A schematic view of a battery assembly with the upper housing removed is shown.

[0036] Figure 1 and Figure 2 are diagrams for explaining a battery assembly according to an embodiment.

[0037] Referring to Figure 1 and Figure 2 , a battery assembly 100 according to an embodiment may include a plurality of battery cells 10 and a housing 30. For example, the battery assembly 100 may correspond to various devices, such as a battery module, a battery pack, or an energy storage system (ESS).

[0038] The plurality of battery cells 10 may be accommodated in the internal space of the housing 30. Each of the plurality of battery cells 10 may be a secondary battery capable of being charged and discharged multiple times. For example, the secondary battery may be one of various types, such as a lithium-ion battery, a lithium polymer battery, a nickel-metal hydride battery, a nickel-cadmium battery, a sodium battery, or a solid-state battery.

[0039] Each of the plurality of battery cells 10 may include a main body 11 and a tab 15.

[0040] The main body 11 may include an electrode assembly and an external material. The electrode assembly may include a plurality of electrodes and an electrolyte. The electrodes may include an anode and a cathode. The anode and the cathode may be alternately stacked. The anode and the cathode may convert chemical energy into electrical energy through a redox reaction. In one embodiment, the electrode assembly may further include a separator. The separator may be disposed between the anode and the cathode such that the anode and the cathode do not contact each other. The electrolyte may be, for example, a medium for transferring ions or current between the anode and the cathode.

[0041] The external material can accommodate the electrode assembly. For example, the external material can surround the electrode assembly. In some embodiments, the space enclosed or surrounded by the external material may be referred to as the "internal space". In some embodiments, the electrode assembly can be accommodated in the internal space of the external material. In one embodiment, the external material can be a pouch film. In one example, when the electrode assembly is accommodated in the internal space of the external material, a portion of the external material can be sealed. For example, when the external material surrounds or wraps the electrode assembly, a portion of the external material may contact another portion, and the contacted area can be sealed by pressing and / or heating. In one embodiment, the pouch film can include at least one of nylon, aluminum, or chlorinated polypropylene (CPP). The above embodiments are merely examples, and the external material can have various shapes, such as a prismatic shape or a cylindrical shape, and can be implemented to include various materials, such as aluminum, alloy materials, and / or composite materials.

[0042] The tab 15 can be electrically connected to the electrode assembly. For example, the tab 15 can include an anode tab connected to the negative electrode of the electrode assembly and a cathode tab connected to the positive electrode of the electrode assembly. In one embodiment, a portion of the tab 15 can be accommodated in the internal space of the external material, and another portion can protrude from the external material. The portion of the tab 15 accommodated in the internal space of the external material can be connected to the electrode of the electrode assembly.

[0043] The tab 15 can protrude from the external material of the main body 11. For example, the tab 15 can protrude in the first horizontal direction (e.g., the Y-axis direction). In some embodiments, the first horizontal direction (e.g., the Y-axis direction), the second horizontal direction (e.g., the X-axis direction), and the height direction (e.g., the Z-axis direction) can be perpendicular to each other. However, the technology disclosed herein is not limited thereto, and the protruding direction of the tab 15 can be variously modified and implemented to be arranged in different directions, such as in the height direction (e.g., the Z-axis direction). In one embodiment, a pair of tabs 15 can protrude from the same side end of the external material respectively. In another embodiment, a pair of tabs 15 can protrude from different side ends of the external material respectively.

[0044] In one embodiment, a plurality of battery cells 10 can be stacked and disposed in the internal space. For example, a plurality of battery cells 10 can be stacked along the second horizontal direction (e.g., the X-axis direction). As another example, a plurality of battery cells 10 can be stacked along the height direction (e.g., the Z-axis direction).

[0045] The housing 30 can accommodate a plurality of battery cells 10. For example, the housing 30 can form an internal space. Here, the internal space can be a space enclosed or surrounded by the housing 30. In one embodiment, the housing 30 can include a hexahedron with an empty internal space, but is not limited thereto, and can be formed in various shapes.

[0046] In one embodiment, the housing 30 can include an upper housing 40, a lower housing 50, and side housings 60. In one embodiment, the upper housing 40, the lower housing 50, and the side housings 60 can be joined to each other using, for example, welding, bolts, etc.

[0047] The upper housing 40 can be disposed on the upper side of the plurality of battery cells 10. In some embodiments, the upper side can refer to the upper portion of the plurality of battery cells 10 in the positive height direction (e.g., +Z-axis direction). The lower housing 50 can be disposed on the lower side of the plurality of battery cells 10. In some embodiments, the lower side can refer to the lower portion of the plurality of battery cells 10 in the negative height direction (e.g., -Z-axis direction). The side housings 60 can be disposed on the left and right sides of the plurality of battery cells 10. In some embodiments, the left side can refer to the side portion of the plurality of battery cells 10 in the positive first horizontal direction (e.g., +Y-axis direction), and the right side can refer to the side portion of the plurality of battery cells 10 in the negative first horizontal direction (e.g., -Y-axis direction). In one embodiment, the battery assembly 100 can further include a bus bar 70 disposed between the side housings 60 and the plurality of battery cells 10.

[0048] In one embodiment, the lower housing 50 can include a lower plate 51 and end plates 55. The lower plate 51 can be disposed on the lower side of the plurality of battery cells 10. The lower plate 51 can support the plurality of battery cells 10. The end plates 55 can be disposed on each of the front and rear sides of the plurality of battery cells 10. In some embodiments, the front side can refer to the side portion of the plurality of battery cells 10 in the positive second horizontal direction (e.g., +X-axis direction), and the rear side can refer to the side portion of the plurality of battery cells 10 in the negative second horizontal direction (e.g., -X-axis direction). A pair of end plates 55 can apply pressure to the main body 11 of the plurality of battery cells 10 disposed therebetween. Figure 1 The lower plate 51 and the end plates 55 are shown as being manufactured as a single integrated component, but this is merely an example, and the lower plate 51 and the end plates 55 can be manufactured as separate components.

[0049] In one embodiment, the battery assembly 100 may further include auxiliary elements associated with the battery cells. In some embodiments, the term "auxiliary element" may be used to denote components, materials, and / or structures that enhance the functionality and / or structural stability of the battery cells. The auxiliary elements may be accommodated in the interior space of the housing 30. In one embodiment, the auxiliary elements may include busbars 70. The busbars 70 may electrically connect the tabs 15 of the battery cells in the plurality of battery cells 10 to another tab of another battery cell. In this case, two battery cells may be electrically connected to each other through the busbars 70. For example, the tab 15 and the busbar may be welded together while in contact, thereby allowing them to be connected together. Each of the busbars 70 and the tabs 15 may include a conductive material. The conductive material may refer to a material having an electrical conductivity higher than a reference value, such as copper, gold, or silver. In one embodiment, the auxiliary elements may include at least one of various auxiliary materials related to the functionality of the battery cells 10, such as cooling plates and thermal adhesives.

[0050] In one embodiment, the battery assembly 100 may further include a plurality of particulate insulating materials. The plurality of particulate insulating materials may be accommodated in the interior space of the housing 30.

[0051] In some embodiments, the techniques disclosed herein may be implemented to improve the stability of the battery assembly 100 and the thermal insulation and / or electrical insulation in the battery assembly 100. Hereinafter, the battery assembly 100 will be described in more detail with reference to the accompanying drawings.

[0052] Figure 3 A schematic diagram of a battery assembly 100 including a plurality of particulate insulating materials 80 based on an embodiment is shown.

[0053] Figure 4 A schematic diagram of a battery assembly 100 including a plurality of particulate insulating materials 80 based on another embodiment is shown.

[0054] Referring to Figure 1 、 Figure 3 and Figure 4 , based on an embodiment, the battery assembly 100 may include a housing 30; a plurality of battery cells 10 accommodated in a part of the interior space of the housing 30; and a plurality of particulate insulating materials 80 accommodated in another part of the interior space of the housing 30.

[0055] In one embodiment, the plurality of battery cells 10 are accommodated in a first interior space of the housing; and the plurality of particulate insulating materials are located in a second interior space of the housing.

[0056] In one embodiment, the internal space may include a first internal space, a second internal space, and a third internal space, which are not physically divided within the outer shell.

[0057] In one embodiment, the first internal space may refer to the space occupied by the plurality of battery cells 10 within the outer shell, the third internal space may refer to the space occupied by the auxiliary components, and the second internal space may refer to the space within the outer shell other than the first internal space and the third internal space.

[0058] The plurality of battery cells 10 and the plurality of particulate insulating materials 80 may be accommodated in the internal space of the outer shell 30. After the plurality of battery cells 10 are disposed in the internal space of the outer shell 30, the particulate insulating materials 80 may be disposed (or a part of the internal space may be filled). For example, the plurality of particulate insulating materials 80 may be disposed in the empty space within the internal space of the outer shell 30 other than the space occupied by the plurality of battery cells 10 (or the plurality of battery cells 10 and the auxiliary components).

[0059] In one embodiment, each of the plurality of battery cells 10 may include an outer material that houses an electrode assembly and a tab 15 protruding from the outer material, and some of the plurality of particulate insulating materials 80 may be disposed between the tabs 15 of the plurality of battery cells 10.

[0060] In one embodiment, some of the plurality of particulate insulating materials 80 may be disposed between the tabs 15 of the plurality of battery cells 10. In one example, the plurality of particulate insulating materials 80 may include particulate insulating materials disposed between the tab 15 of a battery cell 10 and the tab of another battery cell. In one embodiment, some of the plurality of particulate insulating materials 80 may be disposed between the tab 15 of a battery cell 10 and the bus bar 70.

[0061] In one embodiment, some of the plurality of particulate insulating materials 80 may be placed between the plurality of battery cells 10 and the upper outer shell 40 of the outer shell 30. In one example, the plurality of particulate insulating materials 80 may include particulate insulating materials disposed between the plurality of battery cells 10 and the upper outer shell 40.

[0062] In one embodiment, the properties of one of the plurality of particulate insulating materials 80 may include electrical insulation. In one embodiment, the properties of each of the plurality of particulate insulating materials 80 may include electrical insulation. For example, the particulate insulating material 80 may be a material having a resistivity higher than a certain threshold level or reference value. In some embodiments, the resistivity (or specific resistance) of the material may quantitatively represent its electrical insulation property, which refers to its ability to impede the flow of electric current. For example, the higher the resistivity, the better the electrical insulation, which means that the flow of electric current may be blocked more effectively. In some embodiments of the technology disclosed herein, the particulate insulating material 80 may prevent electric current from flowing from the tab 15 or the bus bar 70 to an unintended location.

[0063] In one embodiment, the properties of one of the plurality of particulate insulating materials 80 may further include at least one of heat insulation and flame retardancy. In one embodiment, the properties of each of the plurality of particulate insulating materials 80 may further include at least one of heat insulation and flame retardancy. For example, with respect to heat insulation, the particulate insulating material may be a material having a thermal conductivity lower than or equal to a reference value. In some embodiments, the thermal conductivity may quantitatively represent the heat insulation property of the material, and the heat insulation property refers to its ability to impede heat transfer. For example, the lower the thermal conductivity, the better the heat insulation, which means that heat transfer may be blocked more effectively. In some embodiments of the technology disclosed herein, heat transfer from one cell 10 to adjacent cells may be minimized by the particulate insulating material 80.

[0064] For example, with respect to flame retardancy, the particulate insulating material may be a material that releases a total heat amount lower than a specific threshold or reference value when heated for a specific time. In some embodiments, the flame retardancy may refer to the fire resistance property of the material. For example, the less total heat is released, the better the flame retardancy, which means that the material is less likely to burn. In some embodiments of the technology disclosed herein, the combustion phenomenon may be minimized by the particulate insulating material 80.

[0065] In one embodiment, the battery assembly may further include auxiliary elements for the cells 10 in a part of the internal space, and the ratio of the total volume of the plurality of particulate insulating materials 80 to the volume of the second internal space may be 25% or more and 90% or less.

[0066] In one embodiment, the auxiliary elements are accommodated in a third internal space of the housing.

[0067] In one embodiment, the battery assembly 100 may further include auxiliary elements for the battery cells. In one instance, the auxiliary elements may be accommodated in the internal space of the housing 30. In one instance, the auxiliary elements may include bus bars 70.

[0068] In one embodiment, the ratio of the total volume of the plurality of particulate insulating materials 80 to the volume corresponding to the internal space of the housing 30 excluding the plurality of battery cells 10 and the auxiliary elements may be 25% or more and 90% or less. In one embodiment, when the ratio is less than 25%, the amount of the particulate insulating materials 80 may be insufficient, making it difficult to prevent the flow of high-temperature gases and / or particles in the case of thermal runaway of the battery cells 10. Due to the flow of high-temperature gases and / or particles, heat can be easily transferred to adjacent battery cells. In one embodiment, when the ratio is greater than 90%, the weight of the battery assembly 100 increases, which may reduce the energy efficiency, especially when the battery assembly 100 is applied to a mobile device such as a vehicle due to the increased weight.

[0069] For example, the volume of the entire internal space of the housing 30, excluding the plurality of battery cells 10 and the auxiliary elements, may be a value obtained by subtracting the volumes of the plurality of battery cells 10 and the auxiliary elements accommodated in the internal space of the housing 30 from the total volume of the internal space of the housing 30. In some embodiments, the percentage value obtained by dividing the total volume of the plurality of particulate insulating materials 80 by the above value may be the above ratio.

[0070] In one embodiment, the particulate insulating materials 80 may be in a solid state. The particulate insulating materials 80 implemented based on some embodiments of the technology disclosed herein can prevent problems such as leakage through the gaps of the housing 30 that may occur when injecting a liquid filling material into the internal space of the housing 30.

[0071] The particulate insulating materials 80 implemented based on some embodiments of the technology disclosed herein can prevent problems such as gaps and uneven filling that may occur in the structure and shape of the internal space when inserting a solid-state filling member formed in an integral type into the internal space of the housing 30.

[0072] In one embodiment, referring to Figure 4 , the battery assembly 100 may further include bus bars 70 that electrically connect the plurality of battery cells 10. Each of the plurality of battery cells 10 may include a main body 11 that houses an electrode assembly and a tab 15 that protrudes from the main body 11. The bus bars 70 may be disposed between the main body 11 and the side housing 60 of the housing 30. The bus bars 70 may be electrically connected to the tabs 15.

[0073] In one embodiment, the filling rate of the granular insulating material 81 accommodated between the main body 11 and the bus bar 70 can be greater than the filling rate of the granular insulating material between the bus bar 70 and the side housing 60 of the housing 30. The filling rate can represent the proportion of the total volume of the granular insulating material occupying the space relative to the volume of the corresponding space (e.g., in %). In some embodiments, the granular insulating material 81 is disposed between the main body 11 and the bus bar 70, and the granular insulating material is not disposed between the bus bar 70 and the side housing 60 of the housing 30.

[0074] As described above, by reducing the filling rate between the bus bar 70 and the side housing 60 of the housing 30, the weight increase caused by unnecessary granular insulating material can be minimized, and the material cost can be reduced. In some embodiments, when the battery cell 10 expands due to the charge / discharge cycle of the battery cell 10, by increasing the filling rate between the main body 11 and the bus bar 70, the granular insulating material 81 can exert pressure on the main body 11, thereby achieving uniform surface pressure. This can prevent or delay venting, in which case the main body 11 may open. Therefore, the life of the battery cell 10 can be extended.

[0075] In one embodiment, the battery assembly 100 can include a shielding member covering the bus bar 70. In one embodiment, the shielding member can be disposed between the bus bar 70 and the side housing 60. In this case, it can prevent the residual gas from flowing through the space between the bus bar 70 and the side housing 60.

[0076] Figure 5 An enlarged view of a plurality of granular insulating materials based on an embodiment is shown. Figure 5 A plurality of granular insulating materials filled into the internal space of the housing are shown.

[0077] Refer to Figure 3 、 Figure 4 and Figure 5, the diameter D of at least one of the plurality of granular insulating materials 80 may be 1 mm or more and 15 mm or less. In one embodiment, the diameter D of each of the plurality of granular insulating materials 80 may be 1 mm or more and 15 mm or less. In other words, the lower limit may be 1 mm and the upper limit may be 15 mm. Since the diameter D is 1 mm or more, the granular insulating material 80 can prevent leakage or intrusion into the interior of the battery cell 10 through the gaps of the housing 30. The granular insulating material 80 may be disposed between the battery cell 10 and the bus bar 70. To this end, the diameter of the granular insulating material 80 may be less than the thickness of the battery cell 10. For example, the thickness of the battery cell 10 may be 15 mm. In this case, the diameter D of the granular insulating material 80 may be 15 mm or less. The lower limit and the upper limit of the diameter D are merely examples, and the lower limit and the upper limit of the diameter D may be modified to have various values according to the tolerance of the housing 30 or the type of the battery cell 10.

[0078] In some embodiments of the technology disclosed herein, even when the structure and shape of the interior space of the housing become complicated due to its small diameter, the granular insulating material 80 can uniformly fill the interior space while minimizing voids.

[0079] In one embodiment, the hardness of at least one of the plurality of granular insulating materials 80 is higher than or equal to a first hardness value and lower than or equal to a second hardness value higher than the first hardness value, and the first hardness value may be higher than the hardness value at which the granular insulating material 80 is damaged by vibration.

[0080] In one embodiment, the hardness of at least one of the plurality of granular insulating materials 80 may be higher than or equal to a first hardness value and less than or equal to a second hardness value. In one embodiment, the hardness of each of the plurality of granular insulating materials 80 may be higher than or equal to a first hardness value and less than or equal to a second hardness value. In some embodiments, the second hardness value may have a value higher than the first hardness value. A higher hardness value may indicate that the surface of the material is harder.

[0081] In one embodiment, the first hardness value may be higher than the hardness value at which the granular insulating material 80 is damaged by vibration. The hardness value at which the granular insulating material 80 is damaged by vibration refers to the hardness at which the granular insulating material 80 has low strength and may be damaged by vibration or impact, thereby deteriorating its performance. When the hardness of the granular insulating material 80 is lower than the first hardness value, the granular insulating material 80 may be damaged because it cannot withstand the pressure caused by the gas or particles inside the housing 30. In this case, the performance of the granular insulating material 80 (such as heat insulation) may deteriorate, and the heat transfer of the battery cell 10 may not be suppressed.

[0082] In one embodiment, each of the plurality of battery cells 10 may include an electrode assembly and an external material that houses the electrode assembly, and the second hardness value may be lower than the hardness value of the external material.

[0083] In one embodiment, the second hardness value may be lower than the hardness of the external material of the battery cell 10. When the hardness of the particulate insulating material 80 is higher than the second hardness value, the particulate insulating material 80 may damage the external material of the battery cell 10. In this case, the electrode assembly of the battery cell 10 may be damaged, resulting in thermal runaway.

[0084] In one embodiment, the first hardness value may be Shore hardness A5. In other words, the hardness of the particulate insulating material 80 may be Shore hardness A5 or higher. In one embodiment, the second hardness value may be Shore hardness A95. In other words, the hardness of the particulate insulating material 80 may be Shore hardness A95 or lower. The above Shore hardness A5 and A95 may be values based on the standardized Shore hardness test classification. In one embodiment, the Shore hardness may be measured using a Shore A type measuring device based on ASTM D2240 conditions. For example, the particulate insulating material 80 may be pressed with the hardness tester of the measuring device and left stationary for 30 seconds, and then the value displayed on the measuring device may be read to measure the hardness. However, the technology disclosed herein is not limited to the above examples, and the hardness value may be measured using various measurement methods.

[0085] In one embodiment, the withstand voltage of the diameter of one of the plurality of particulate insulating materials 80 may be higher than or equal to the first withstand voltage. The diameter of the particulate insulating material 80 may represent the thickness of the particulate insulating material 80. The withstand voltage refers to the voltage at which the electrical insulation is broken, and when the voltage applied to a sample of a specific thickness (e.g., the particulate insulating material 80) increases, an overcurrent begins to flow. In other words, a high withstand voltage may indicate excellent electrical strength as an insulating material. In one embodiment, the withstand voltage may be measured under ASTM D149 conditions. For example, the sample may be placed on a measuring device in a stable environment at 25 degrees Celsius, and the voltage may be increased at a rate of 0.5 kV / second. Then, the test may be continuously performed until an overcurrent flows through the sample, and the value at this time point may be recorded as the withstand voltage.

[0086] In one embodiment, each of the plurality of battery cells 10 may include an external material that houses the electrode assembly and a tab 15 that protrudes from the external material, and the first withstand voltage may be higher than the value obtained by dividing the overvoltage applied to the tab 15 by the diameter D of at least one of the plurality of particulate insulating materials 80.

[0087] In one embodiment, the first withstand voltage can be higher than the overvoltage applied to the tab 15 (or the bus bar 70) and the value corresponding to the diameter D. For example, the overvoltage applied to the tab 15 (or the bus bar 70) can vary according to the operating environment of the battery assembly 100. Considering the operating environment of the battery assembly 100, the first withstand voltage can be set to a value higher than the value obtained by dividing the overvoltage by the diameter D. When the withstand voltage of the granular insulating material 80 is lower than the first withstand voltage, the overvoltage may damage the electrical insulation performance of the granular insulating material 80. In this case, leakage current may flow through the granular insulating material 80, which may lead to a short circuit and thus cause a fire accident.

[0088] In one embodiment, the first withstand voltage can be 1 kV / mm. In this case, the withstand voltage of the granular insulating material 80 can be 1 kV / mm or more. At the same time, the 1 kV / mm representing the lower limit of the withstand voltage is only an example, and the lower limit can be modified to various values according to the type, quantity, voltage, etc. of the battery cell 10.

[0089] In one embodiment, the withstand voltage of the granular insulating material 80 can be lower than the second withstand voltage. In some embodiments, the second withstand voltage can be higher than the first withstand voltage. In one embodiment, the second withstand voltage can be 30 kV / mm. In this case, the withstand voltage of the granular insulating material 80 can be 30 kV / mm or less. For example, in order to ensure that the withstand voltage of the granular insulating material 80 exceeds 30 kV / mm, the cost may increase.

[0090] Figure 6 A schematic diagram showing the shape of the granular insulating material based on the embodiment is shown.

[0091] Referring to Figure 5 and Figure 6 , the cross-sectional shape of one of the granular insulating materials 80 based on the embodiment can be one of a circle 80a, an ellipse 80b, polygons 80c and 80d, and an amorphous shape 80e. The cross-sectional shape of each of the plurality of granular insulating materials 80 based on the embodiment can be one of a circle 80a, an ellipse 80b, polygons 80c and 80d, and an amorphous shape 80e. For example, the cross-sectional shape can be a planar shape (e.g., XY plane, YZ plane, etc.) obtained by cutting a part of the granular insulating material 80.

[0092] In one embodiment, the granular insulating material 80 can include core portions 81a to 81e and coating portions 83a to 83e covering the surfaces of the core portions 81a to 83e. However, the techniques disclosed herein are not limited to these examples. For example, the coating portions 83a to 83e can be omitted.

[0093] In one embodiment, the cores 81a to 81e may include at least one of an inorganic material and a foam material, and the coating portions 83a to 83e may include at least one of an inorganic material and a foam material. In one embodiment, the inorganic material may include at least one of materials such as silica gel, glass, and ceramics. In one embodiment, the foam material may include at least one of materials such as epoxy resin, urethane, polyurethane, polyolefin, urea resin, and phenolic resin.

[0094] In one example, one of the cores 81a to 81e and the coating portions 83a to 83e may include a material not included in the other. In other words, one of the cores 81a to 81e and the coating portions 83a to 83e may include a material different from the other. For example, the cores 81a to 81e may include an inorganic material, and the coating portions 83a to 83e may include a foam material. This is to supplement the insulation or hardness of the inorganic material through the coating portions 83a to 83e. As another example, the cores 81a to 81e may include a foam material, and the coating portions 83a to 83e may include an inorganic material. This is to relatively reduce the proportion of the inorganic material to reduce the overall weight. In addition, various embodiments are possible. For example, the cores 81a to 81e include an inorganic material and a foam material, and the coating portions 83a to 83e include a foam material.

[0095] The technology disclosed herein can be implemented in rechargeable secondary batteries, which are widely used in battery-powered devices or systems, including, for example, digital cameras, mobile phones, laptop computers, hybrid vehicles, electric vehicles, uninterruptible power supplies, battery energy storage power stations, and other devices including battery energy storage for solar panels, wind turbines, and other green technology generators. Specifically, the technology disclosed herein can be implemented in some embodiments to provide improved electrochemical devices, such as batteries for various power sources and power supplies, thereby alleviating climate change associated with the use of power sources and power supplies. The secondary battery based on the technology disclosed herein can be used to address various adverse effects, such as air pollution and greenhouse gas emissions, by powering electric vehicles (EVs) as an alternative to vehicles using fossil fuel-based engines and by providing a battery-based energy storage system (ESS) to store renewable energy such as solar and wind energy.

[0096] Only several embodiments and examples are described herein. Improvements and variations can be made to the disclosed embodiments and other embodiments based on the content described and illustrated in this application document.

Claims

1. A battery assembly, comprising: shell; a plurality of battery cells accommodated in the first interior space of the housing; and A plurality of granular insulating materials are contained within the second interior space of the housing.

2. The battery assembly according to claim 1, wherein: At least one of the plurality of granular insulating materials has a hardness value greater than or equal to a first hardness value and less than or equal to a second hardness value, the second hardness value being greater than the first hardness value, wherein the first hardness value is greater than a third hardness value when the granular insulating material is damaged by vibration.

3. The battery assembly of claim 2, wherein the first hardness value is Shore A5.

4. The battery assembly according to claim 2, wherein each of the plurality of battery cells comprises: Electrode assembly; and an outer material configured to receive the electrode assembly, wherein the second hardness value is lower than a hardness value of the outer material.

5. The battery assembly according to claim 2, wherein the second hardness value is Shore A 95.

6. The battery assembly according to claim 1, wherein each of the plurality of battery cells comprises: Electrode assembly; a body configured to accommodate the electrode assembly; and a tab protruding from the main body, wherein the battery assembly further comprises a bus bar disposed between the main bodies of the plurality of battery cells and the outer shell and electrically connected to the tab, wherein, among the plurality of granular insulating materials, a filling rate of the granular insulating material disposed between the main bodies of the plurality of battery cells and the bus bar is higher than a filling rate of the granular insulating material disposed between the bus bar and the outer shell.

7. The battery assembly according to claim 1, wherein: A withstand voltage corresponding to a diameter of at least one of the plurality of granular insulating materials is higher than or equal to a first withstand voltage.

8. The battery assembly according to claim 7, wherein each of the plurality of battery cells comprises: Electrode assembly; an outer material configured to house the electrode assembly; and a tab protruding from the external material, wherein the first withstand voltage is higher than a value obtained by dividing an overvoltage applied to the tab by a diameter of at least one granular insulating material among the plurality of granular insulating materials. 9 . The battery assembly according to claim 7 , wherein the first withstand voltage is 1 kV / mm. 10 . The battery assembly according to claim 9 , wherein the at least one granular insulating material has a withstand voltage of 30 kV / mm or less.

11. The battery assembly according to claim 1, wherein: A cross-sectional shape of at least one of the plurality of granular insulating materials is at least one of a circular shape, an elliptical shape, a polygonal shape, or an amorphous shape.

12. The battery assembly according to claim 11, wherein: The at least one granular insulating material includes a core portion and a coating portion, the coating portion covering the core portion. 13 . The battery assembly according to claim 12 , wherein each of the core portion and the coating portion comprises at least one of an inorganic material or a foam material. 14 . The battery assembly according to claim 13 , wherein one of the core portion and the coating portion includes a material that is not included in the other. 15 . The battery assembly according to claim 1 , wherein at least one of the plurality of granular insulating materials exhibits at least one of thermal insulation and flame retardancy. 16 . The battery assembly according to claim 1 , wherein a diameter of at least one of the plurality of granular insulating materials is 1 mm or more and 15 mm or less.

17. The battery assembly of claim 1, wherein each of the plurality of battery cells comprises an external material configured to accommodate an electrode assembly and tabs protruding from the external material, wherein one or more of the plurality of granular insulating materials are disposed between the tabs of the plurality of battery cells.

18. The battery assembly according to claim 17, further comprising: An auxiliary element is disposed in a third internal space adjacent to the plurality of battery cells, wherein a volume ratio of a total volume of the plurality of granular insulating materials to a volume of the second internal space is greater than or equal to 25% and less than or equal to 90%.

19. The battery assembly according to claim 1, wherein: The case includes an upper case disposed on an upper side of the plurality of battery cells, wherein one or more of the plurality of granular insulating materials are disposed between the plurality of battery cells and the upper case.

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