Battery assembly

Abstract

A battery assembly according to the present disclosure includes: a plurality of battery cells each including a body portion that stores and supplies electric energy and a tab portion that protrudes to an outer side of the body portion so as to electrically connect the body portion and the outside, and stacked in one direction; an accommodating case accommodating the plurality of battery cells therein; a bus bar assembly located inside the accommodating case and including a through hole formed in one surface, the tab portion being inserted into the through hole so as to electrically connect at least parts of the plurality of battery cells to each other; and a cylindrical flame retardant portion located between the body portion and the bus bar assembly in an insertion space formed by the tab portions of two adjacent battery cells among the plurality of battery cells.

Description

Technical Field

[0001] The present disclosure relates to a battery assembly. Background Art

[0002] A secondary battery stores electrical energy as chemical energy and can be reused through multiple charging and discharging cycles. Due to its economic and environmentally friendly characteristics, secondary batteries are widely used in the entire industry. In particular, lithium secondary batteries among secondary batteries are widely used in the entire industry including portable devices that require high-density energy.

[0003] The operating principle of a lithium secondary battery is an electrochemical oxidation-reduction reaction. That is, its principle is to generate electricity through the movement of lithium ions, and to charge through the reverse process. In a lithium secondary battery, the phenomenon of lithium ions escaping from the anode and passing through the electrolyte and separator to move to the cathode is called discharging. Then, the reverse process of this phenomenon is called charging.

[0004] During charging and discharging of a secondary battery, a large amount of heat can be generated. When the heat generated inside cannot be quickly suppressed, the fire can spread to adjacent battery cells, causing huge losses. Therefore, one of the main problems is to quickly suppress the heat generated inside the secondary battery and prevent the spread of fire.

[0005] For high-capacity and high-power characteristics, multiple secondary batteries can be combined to form a battery module or a battery pack. At this time, due to a fire occurring in any one of the multiple secondary batteries, the battery module or battery pack may be burned. Therefore, it is necessary to prevent such a danger. Summary of the Invention

[0006] The problem that the present disclosure wants to solve is to delay the spread of fire to adjacent battery cells, thereby improving the stability of the battery assembly.

[0007] In addition, the present disclosure can be widely applied in green technology fields such as electric vehicles, battery charging stations, solar power generation, and wind power generation that use batteries in addition.

[0008] In addition, the present disclosure can be applied in eco-friendly electric vehicles, hybrid vehicles, etc. that are used to suppress air pollution and greenhouse gas emissions to prevent climate change.

[0009] The battery assembly of the present disclosure includes: a plurality of battery cells, each including a body portion and a tab portion, and stacked along a direction, the body portion storing and supplying electric energy, the tab portion protruding outward from the body portion to electrically connect the body portion and the outside; a housing case that houses the plurality of battery cells therein; a bus bar assembly located inside the housing case, including a through hole formed on one surface, the tab portion being inserted into the through hole to electrically connect at least a part of the plurality of battery cells to each other; and a cylindrical flame retardant portion located in an insertion space formed between the tab portions of two adjacent battery cells among the plurality of battery cells between the body portion and the bus bar assembly.

[0010] Optionally, the housing case includes: a housing main body that supports the plurality of battery cells; and a housing cover that is coupled to the housing main body and covers the plurality of battery cells, the flame retardant portion being located on the housing main body.

[0011] Optionally, the flame retardant portion may be in contact with the housing main body.

[0012] Optionally, along the height direction formed perpendicular to the protruding direction of the tab portion and the stacking direction in which the plurality of battery cells are stacked, the length of the flame retardant portion may be equal to or less than the length of the body portion.

[0013] Optionally, along the height direction formed perpendicular to the protruding direction of the tab portion and the stacking direction in which the plurality of battery cells are stacked, the length of the flame retardant portion may be 80% or more of the length of the body portion.

[0014] Optionally, along the stacking direction in which the plurality of battery cells are stacked, the length of the flame retardant portion is equal to or less than the interval between the tab portions provided in each of two adjacent battery cells among the plurality of battery cells.

[0015] Optionally, the flame retardant portion includes a head portion formed at one end, a bottom portion formed at the other end opposite to the one end, and a main body portion connecting the head portion and the bottom portion, the head portion and the bottom portion having a shape in which the cross-sectional area decreases along the direction from the main body portion toward their respective outermost sides.

[0016] Optionally, each of the head portion and the bottom portion includes a flat surface formed perpendicular to the extending direction of the main body portion.

[0017] Optionally, each of the head portion and the bottom portion has a conical shape in which one end including a vertex is cut off.

[0018] Optionally, the head portion has the same shape as the bottom portion.

[0019] Optionally, the outer side surface of the main body portion is formed as a curved surface.

[0020] Optionally, the main body portion is cylindrical.

[0021] Optionally, the flame retardant portion includes a material having a flame retardant rating of V0 or higher according to the UL94 standard.

[0022] Optionally, the flame retardant portion includes flame retardant polyurethane.

[0023] According to an embodiment of the present disclosure, it is possible to delay the spread of fire to adjacent battery cells, thereby improving the stability of the battery assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a diagram showing a battery cell according to an embodiment of the present disclosure.

[0025] Figure 2 is a diagram showing a battery assembly according to an embodiment of the present disclosure.

[0026] Figure 3 and Figure 4 is a diagram showing a cross-section of a battery assembly according to an embodiment of the present disclosure.

[0027] Figure 5 is a diagram showing a battery cell and a flame retardant portion according to an embodiment of the present disclosure.

[0028] Figure 6 is a diagram showing a flame retardant portion according to an embodiment of the present disclosure.

[0029] Figure 7 is a diagram showing a head according to an embodiment of the present disclosure.

[0030] Reference Signs: 100: Battery assembly, 110: Battery cell, 120: Accommodating housing, 130: Bus bar assembly, 140: Flame retardant portion, 150: End cover, 160: Insertion space, 170: Blocking portion. DETAILED DESCRIPTION

[0031] Hereinafter, the present disclosure will be described in detail with reference to the drawings. However, it is merely an example, and the present disclosure is not limited to the specific embodiments described by way of example.

[0032] The specific terms used in this specification are only for convenience of description and are not used to limit the embodiments of the examples.

[0033] For example, expressions such as "same" and "identical" not only represent strictly the same state, but also represent a state in which there are tolerances or differences in the degree of obtaining the same function.

[0034] For example, expressions indicating relative or absolute configurations such as "a certain direction", "along a certain direction", "parallel", "perpendicular", "centered on", "concentric", or "coaxial" not only represent such configurations in the strict sense but also represent states of relative displacement in terms of angles or distances with tolerances or achieving the same functional degree.

[0035] To illustrate the present disclosure, it is described based on a three-dimensional rectangular coordinate system formed by an X-axis, a Y-axis, and a Z-axis that are perpendicular to each other. Each axis direction (X-axis direction, Y-axis direction, Z-axis direction) represents the two side directions in which each axis extends.

[0036] The X-direction, Y-direction, and Z-direction mentioned below are described for clearly understanding the present disclosure, and it should be clear that each direction can also be defined differently depending on the reference point.

[0037] The expressions such as "first", "second", "third", etc. used before the components mentioned below are only for avoiding the mixing of the components being referred to and have nothing to do with the order, importance, or master-slave relationship between the components. For example, an invention that includes only the second component without the first component can also be implemented.

[0038] When not clearly stated in the context, the singular expressions used in this specification include the plural expressions.

[0039] Figure 1 FIG. is a view showing a battery cell 110 according to an embodiment of the present disclosure, Figure 2 FIG. is a view showing a battery assembly 100 according to an embodiment of the present disclosure.

[0040] The battery cell 110 described in this specification may include a secondary battery that can charge and discharge electrical energy and can be reused. As an example, it may refer to a lithium secondary battery or a lithium-ion battery, but is not limited thereto. As another example, it may refer to a all-solid-state battery.

[0041] The battery cell 110 may be divided into a pouch-type secondary battery, a prismatic secondary battery, or a cylindrical secondary battery according to its shape. In this specification, for convenience of description, a pouch-type secondary battery is shown as an example, but is not limited thereto.

[0042] Reference Figure 1 , the battery cell 110 may include a body portion 111 and a tab portion 112. The body portion 111 may store and supply electrical energy. The body portion 111 may include a positive electrode and a negative electrode. As an example, the body portion 111 may include an electrode assembly formed by laminating a positive electrode and a negative electrode.

[0043] The positive electrode may include a positive electrode active material, and the negative electrode may include a negative electrode active material. The positive electrode active material may be a material capable of intercalating and deintercalating lithium ions, and the negative electrode active material may be a material capable of adsorbing or deintercalating lithium ions.

[0044] The tab portion 112 may protrude outward from the main body portion 111. The tab portion 112 may be connected to each of the positive electrode and the negative electrode, so as to protrude outward from the main body portion 111. The tab portion 112 may include a positive electrode tab 112a connected to the positive electrode and a negative electrode tab 112b connected to the negative electrode.

[0045] In an embodiment, the positive electrode tab 112a and the negative electrode tab 112b may protrude in opposite directions from each other. For example, referring to Figure 1 , the positive electrode tab 112a may protrude along the +X direction, and the negative electrode tab 112b may protrude along the -X direction.

[0046] The tab portion 112 may electrically connect the main body portion 111 to the outside. The tab portion 112 may be connected to each of the positive electrode and the negative electrode of the main body portion 111, so as to supply the electric energy stored in the main body portion 111 to the outside.

[0047] On the one hand, the battery assembly 100 described in this specification refers to combining one or more battery cells 110 and placing them in a housing to protect the battery cells 110 from external impacts, heat, vibrations, etc. and having high power and high capacity characteristics. For example, the battery assembly 100 may refer to a battery module or a battery pack. In this specification, for the convenience of description, the battery module is described as an example of the battery assembly 100.

[0048] Referring to Figure 2 , the battery assembly 100 of the present disclosure may include a plurality of battery cells 110 and a housing 120 that houses the battery cells 110 therein. This is to protect the battery cells 110 from external foreign objects or impacts and assemble the battery cells 110 into a single unit.

[0049] The housing 120 may include: a housing main body 121 that houses a plurality of battery cells 110; and a housing cover 122 that is coupled to the housing main body 121 to form a space for housing a plurality of battery cells 110 together with the housing main body 121.

[0050] The housing main body 121 may include an opening 1211 that opens upward, and a plurality of battery cells 110 are housed through the opening 1211. The housing cover 122 may be coupled to the housing main body 121 to close the opening 1211.

[0051] The battery assembly 100 may further include end covers 150. The end covers 150 may be coupled to both sides of the accommodation body 121 to form the sides of the accommodation space. For example, the end covers 150 may be coupled to the accommodation body 121 along the X direction.

[0052] Finally, the battery assembly 100 may form a hexahedron through the accommodation housing 120 and the end covers 150. With this structure, the battery cells 110 located inside can be effectively protected from external impacts.

[0053] The battery assembly 100 of the present disclosure may further include a busbar assembly 130. The busbar assembly 130 (Busbar assembly) may be located inside the accommodation housing 120 and includes a perforation 1311 formed on one side ( Figure 3 ), and the pole ear portion 112 is inserted into the perforation 1311. The busbar assembly 130 may electrically connect at least a part of the plurality of battery cells 110 to each other.

[0054] The busbar assembly 130 may include a busbar plate 131 (Busbar plate) and a busbar 132 (Busbar). The busbar plate 131 may extend along the direction of stacking the plurality of battery cells 110. The plurality of battery cells 110 may be arranged with their wide faces facing each other to improve the effectiveness of stacking. For example, referring to Figure 2 , the plurality of battery cells 110 may be stacked along the Y direction.

[0055] The busbar plate 131 may be arranged to face the pole ear portions 112 provided in each of the plurality of battery cells 110. Finally, the busbar plate 131 may be arranged to face the pole ear portions 112 and have a quadrilateral shape extending along the stacking direction of the battery cells 110. There may be a plurality of busbar plates 131.

[0056] The busbar plate 131 may include a perforation 1311 for inserting the pole ear portion 112. The perforation 1311 may have a slot shape with one side open, but is not limited thereto. The pole ear portion 112 may be inserted through the perforation 1311 to connect the plurality of battery cells 110 and the busbar plate 131.

[0057] The busbar 132 may be coupled to one side of the busbar plate 131. In an embodiment, the busbar plate 131 may include a first side facing the pole ear portions 112 of the plurality of battery cells 110 and a second side opposite to the first side. The busbar 132 may be provided on the second side of the busbar plate 131.

[0058] The busbar 132 may include an insertion hole 1321 ( Figure 3). The tab portion 112 can be inserted into the insertion hole 1321. Thereby, the tab portion 112 and the bus bar 132 can be electrically connected. The insertion hole 1321 can be provided at a position corresponding to the perforation 1311 along the insertion direction of the tab portion 112. This is to enable the tab portion 112 to be inserted into the bus bar 132 after being inserted into the bus bar plate 131. Finally, the tab portions 112 can be inserted into the bus bar plate 131 and the bus bar 132 respectively.

[0059] The bus bar assembly 130 can include at least one bus bar 132. Thereby, a plurality of battery cells 110 can be electrically connected in series or in parallel.

[0060] The battery assembly 100 of the present disclosure can include a flame retardant portion 140. The flame retardant portion 140 can be located in the insertion space 160 formed by the tab portions 112 of two adjacent battery cells 110 among the plurality of battery cells 110 between the body portion 111 and the bus bar assembly 130. The flame retardant portion 140 can be cylindrical, so as to occupy most of the area of the insertion space 160.

[0061] Reference Figure 2 , the flame retardant portion 140 can be located between the bus bar plate 131 and the body portion 111. In addition, the flame retardant portion 140 can be located between the tab portions 112 of any one battery cell 110 and the adjacent other battery cell 110 among the plurality of battery cells 110. That is, the flame retardant portion 140 can occupy the insertion space 160 formed between the tab portions 112 of two adjacent battery cells 110.

[0062] When a fire occurs in a certain battery cell 110, the fire can quickly spread to the adjacent battery cell 110. In particular, the fire can spread through the hollow space inside the battery assembly 100. To prevent this phenomenon, it is necessary to fill the hollow space inside the battery assembly 100 with a flame retardant material. The present disclosure uses the flame retardant portion 140 to fill the insertion space 160, which is the hollow space inside the battery assembly 100, thereby preventing the spread of fire.

[0063] Figure 3 and Figure 4 are diagrams showing cross-sections of the battery assembly 100 according to embodiments of the present disclosure.

[0064] Specifically, Figure 3 and Figure 4 are diagrams showing the situation where the tab portion 112 of the battery cell 110 of the present disclosure is inserted into the bus bar assembly 130. The tab portion 112 can be inserted into the perforation 1311 and the insertion hole 1321, so as to be connected to the bus bar assembly 130. At this time, an insertion space can be formed by the tab portions 112, the body portion 111, and the bus bar assembly 130 of two adjacent battery cells 110. ReferenceFigure 3 , multiple insertion spaces 160 can be formed.

[0065] The flame retardant part 140 can be located in the insertion space 160. The flame retardant part 140 can occupy the area of the insertion space 160 to prevent the spread of fire. The flame retardant part 140 can block the route of fire spread. The flame retardant part 140 can be cylindrical.

[0066] The flame retardant part 140 can be formed in a shape corresponding to the insertion space 160 of the accommodation body 121. In an embodiment, the flame retardant part 140 can be in contact with at least one of the tab part 112, the body part 111, and the bus bar assembly 130.

[0067] Reference Figure 4 , the flame retardant part 140 can be located on the accommodation body 121. The flame retardant part 140 can be fixed on the accommodation body 121, but is not limited thereto. The flame retardant part 140 can be in contact with the accommodation body 121.

[0068] On the one hand, the battery assembly 100 of the present disclosure can further include a blocking part 170. The blocking part 170 can be located between the plurality of battery cells 110. The blocking part 170 can be stacked with the plurality of battery cells 110 along the stacking direction of the plurality of battery cells 110. Reference Figure 3 , the blocking part 170 can be located between two adjacent battery cells 110. The blocking part 170 can be formed of a flame retardant material to prevent the spread of fire.

[0069] Figure 5 is a diagram showing the battery cell 110 and the flame retardant part 140 according to an embodiment of the present disclosure.

[0070] The flame retardant part 140 can be cylindrical. The flame retardant part 140 can extend along the height direction formed perpendicular to the protruding direction of the tab part 112 and the stacking direction of the plurality of battery cells 110. Reference Figure 5 , the height direction refers to the Z direction. That is, the flame retardant part 140 can extend along the Z direction to occupy the insertion space 160 inside the battery assembly 100.

[0071] The length L1 of the flame retardant part 140 can be less than or equal to the length L3 of the body part 111 along the height direction. When the length L1 of the flame retardant part 140 is set to be greater than or equal to the length L3 of the body part 111 along the height direction, the flame retardant part 140 can protrude outward from the body part 111. As a result, the convenience of assembly may be reduced, and it is difficult to effectively use the space. Therefore, the flame retardant part 140 can preferably be set to be less than or equal to the length of the body part 111.

[0072] The length of the flame retardant portion 140 may be 80% or more of the length of the main body portion 111 in the height direction. When the length of the flame retardant portion 140 is less than 80% of the length of the main body portion 111, the fire still spreads to the remaining space of the insertion space 160, so that the spread of the fire may not be prevented.

[0073] Along the stacking direction in which a plurality of battery cells are stacked, the length L2 of the flame retardant portion may be equal to or less than the interval L4 between the tab portions provided in each of two adjacent battery cells among the plurality of battery cells.

[0074] Reference Figure 5 , the battery cells 110 are stacked in the Y direction, so the stacking direction refers to the Y direction. As described above, only when the length of the flame retardant portion 140 in the Y direction is set to be equal to or less than the interval between the tab portions, can the flame retardant portion 140 be stably located in the insertion space 160.

[0075] On the one hand, preferably, the length of the flame retardant portion 140 in the Y direction may be set to be more than half of the interval between the tab portions. With this shape, the flame retardant portion 140 can occupy most of the space of the insertion space 160, and the spread of the fire can be postponed.

[0076] Finally, the flame retardant portion 140 may preferably be formed in a shape for occupying most of the area of the insertion space 160, whereby the route of the spread of the fire can be physically blocked.

[0077] In order to minimize the damage caused by the flame retardant portion 140, the flame retardant portion 140 may preferably have a smooth and flat surface. For example, the flame retardant portion 140 may preferably not include angular edges such as those of a rectangular parallelepiped.

[0078] Figure 6 is a diagram showing the flame retardant portion 140 according to an embodiment of the present disclosure, Figure 7 is a diagram showing the head according to an embodiment of the present disclosure.

[0079] Reference Figure 6 , the flame retardant portion 140 may include a head 141, a main body portion 142, and a bottom portion 143. It may be that the head 141 is formed at one end of the flame retardant portion 140, and the bottom portion 143 is formed at the other end of the flame retardant portion 140 opposite to the one end. The main body portion 142 may connect the head 141 and the bottom portion 143.

[0080] Refer to again Figures 3 to 5 , optionally, the bottom portion 143 faces the accommodating body 121, and the head 141 faces the accommodating cover 122. In addition, the main body portion 142 may extend in the Z direction as the height direction, so that the shape of the flame retardant portion 140 corresponds to the shape of the insertion space 160.

[0081] On the one hand, the cross-sectional areas of the head 141 and the bottom 143 can decrease along the direction from the main body 142 towards their respective outermost sides. For example, referring to Figure 6 , the direction from the main body 142 towards the outermost side of the head 141 refers to the +Z direction. Additionally, this can refer to the direction from the main body 142 towards the head 141.

[0082] The cross-sectional area of the head 141 can decrease along the +Z direction. The cross-sectional area of the head 141 refers to the area of the virtual cross-section obtained by cutting the head 141 along the direction perpendicular to the direction from the main body 142 towards the outermost side of the head 141. In other words, the cross-sectional area of the head 141 refers to the area of the virtual cross-section obtained by cutting the head 141 along the XY plane.

[0083] The head 141 can include a first cross-section 145 relatively close to the main body 142 and a second cross-section 146 relatively close to the outermost side. At this time, the cross-sectional area of the first cross-section 145 can be larger than the cross-sectional area of the second cross-section 146. With this structure, the side surface of the head 141 can be smoothly formed, and the damage to the battery module 100 caused by the flame retardant part 140 can be minimized.

[0084] Referring to the foregoing, the cross-sectional area of the bottom 143 can decrease along the -Z direction. The cross-sectional area of the bottom 143 refers to the area of the virtual cross-section obtained by cutting the bottom 143 along the direction perpendicular to the direction from the main body 142 towards the outermost side of the bottom 143.

[0085] The head 141 and the bottom 143 can each include a flat surface formed perpendicular to the direction in which the main body 142 extends. This is to minimize the damage to the battery module 100 and enable the flame retardant part 140 to stably hold its position in the battery module 100.

[0086] Referring to Figure 6 , the main body 142 can extend along the Z direction, and the XY plane can be formed perpendicular to the Z direction. The head 141 can include a surface parallel to the XY plane. Additionally, the bottom 143 can also include a surface parallel to the XY plane.

[0087] In an embodiment, the head 141 and the bottom 143 can have a conical shape with one end including a vertex being cut. The head 141 and the bottom 143 can each have a plurality of conical shapes with one end including a vertex being cut. The plurality of cones can be such that the bottoms and the edges form different angles with each other.

[0088] Figure 7 The head is illustrated and the head 141 is described, however, this description can also be applicable to the bottom 143. Specifically, the head 141 and the bottom 143 are shapes that are upside down along the Z direction. Therefore, when applying the description related to the head to the bottom, it is only necessary to apply the description of the head in the opposite direction in the Z direction.

[0089] Reference Figure 7 , the head 141 may include a first head 200 and a second head 210. Similarly, the bottom 143 may include a first bottom (not shown) and a second bottom (not shown).

[0090] Each of the first head 200 and the second head 210 may be in a conical shape with one end including a vertex being cut. The first head 200 may include a first lower surface 201 and a first upper surface 211 located on the upper side of the first lower surface 201 along the Z direction. The first lower surface 201 and the first upper surface 211 may be arranged in parallel.

[0091] The first head 200 may include a first side surface 202 connecting the first lower surface 201 and the first upper surface 211. The second head 210 may include a second lower surface 211 and a second upper surface 221 located on the upper side of the second lower surface 211 along the Z direction. The second head may include a second side surface 212 connecting the second lower surface 211 and the second upper surface 221.

[0092] The first head 200 and the second head 210 may be connected to each other to form. Thus, the first head and the second head may share a cross-section 211. Optionally, the cross-section 211 forms the first upper surface 211 of the first head 200 and forms the second lower surface 211 of the second head 210. That is, the first upper surface 211 and the second lower surface 211 may represent the same surface.

[0093] The angle A1 formed by the first lower surface 201 and the first side surface 202 may be formed to be greater than the angle A2 formed by the second lower surface 211 and the second side surface 212. In other words, based on the XY plane, the first side surface may be formed to be steeper than the second side surface. The inclination is gradually formed slowly toward the outermost side along the Z direction, so that the side surface of the head can be formed without edges and corners, and damage caused by the conflict between the head and adjacent components can be minimized.

[0094] In an embodiment, the cross-section obtained by orthographically projecting the second lower surface 211 onto the XY plane may be located within the first lower surface 201. Additionally, the area of the second lower surface 211 may be formed to be smaller than the area of the first lower surface 201. Thus, the inclination can be slowly formed toward the outermost side along the Z direction to form a stable structure.

[0095] In an embodiment, the head 141 and the bottom 143 may be such that their side surfaces are formed as curved surfaces, and each includes flat surfaces 1411 and 1431 provided.

[0096] The flame retardant part 140 can be symmetrical with respect to a virtual plane parallel to the XY plane. In other words, the bottom 143 and the head 141 can be symmetrically formed. Thus, it can be arranged such that the bottom 143 faces the accommodation cover 122 and the head 141 faces the accommodation body 121. By symmetrically arranging the bottom 143 and the head 141, the assembly effectiveness of the battery assembly 100 can be improved. When distinguishing between the bottom 143 and the head 141, the bottom 143 to be inserted faces the accommodation body 121.

[0097] Conversely, when the bottom 143 and the head 141 are symmetrically arranged, there is no need to distinguish between the bottom 143 and the head 141, and the flame retardant part 140 can be inserted into the insertion space 160 as long as it is inserted.

[0098] In addition, the flame retardant part 140 can preferably have a shape that is symmetrical with respect to a virtual plane parallel to the XZ plane and can preferably have a shape that is symmetrical with respect to a virtual plane parallel to the YZ plane.

[0099] The outer side surface of the main body part 142 can be formed as a curved surface. As described above, this is to minimize the damage to the battery assembly 100 caused by the flame retardant part 140. When the main body part 142 has angular edges, the assembly may be damaged through the edges. When the main body part 142 is formed as a curved surface, the pressure applied to adjacent components is dispersed, thereby minimizing the damage caused by the conflict with the flame retardant part 140.

[0100] As an example, the main body part 142 can be formed of a cylinder. Ultimately, the flame retardant part 140 can have the head 141 and the bottom 143 located at both ends of the main body part 142 formed of a cylinder, respectively.

[0101] The flame retardant part 140 can include a fire-resistant and flame-retardant material to minimize the spread of fire. The flame retardant part 140 can include a material whose flame retardant rating is V-0 or above according to the UL94 standard. The UL94 standard classifies the flame retardant rating through a test for evaluating the flame retardancy of plastics. The flame retardant rating can be classified into HB, V2, V1, V0, and 5V. The material with a V2 rating has the lowest flame retardancy and is prone to burning, while the material with a 5V rating has the highest flame retardancy and is not prone to burning.

[0102] The flame retardant part 140 of the present disclosure may include materials above V0 rating. The flame retardant part 140 may include flame retardant materials classified into V0 rating and 5V rating. For example, the flame retardant part 140 may include at least one of flame retardant polyurethane, silica gel, modified polyphenylene oxide (MPPO), polypropylene, polyoxymethylene (acetal), polyamide 6, polyamide 6-6, and polycarbonate.

[0103] The content described above is only an example of applying the principles of the present disclosure, and other structures may also be included without departing from the scope of the present invention.

Claims

1. A battery assembly, comprising: A plurality of battery cells, each including a body portion and a tab portion, and stacked along a direction, the body portion storing and supplying electric energy, and the tab portion protruding outward from the body portion to electrically connect the body portion and the outside; A housing case that houses the plurality of battery cells therein; A bus bar assembly located inside the housing case, including a perforation formed on one surface, and the tab portion is inserted into the perforation to electrically connect at least a part of the plurality of battery cells to each other; And A cylindrical flame retardant portion located in an insertion space formed by the tab portions of two adjacent battery cells among the plurality of battery cells between the body portion and the bus bar assembly.

2. The battery assembly according to claim 1, wherein The housing case includes: A housing main body that supports the plurality of battery cells; and A housing cover that is combined with the housing main body and covers the plurality of battery cells, The flame retardant portion is located on the housing main body.

3. The battery assembly according to claim 2, wherein The flame retardant portion is in contact with the housing main body.

4. The battery assembly according to any one of claims 1 to 3, wherein Along a height direction formed perpendicular to the protruding direction of the tab portion and the stacking direction in which the plurality of battery cells are stacked, the length of the flame retardant portion is equal to or less than the length of the body portion.

5. The battery assembly according to any one of claims 1 to 3, wherein Along a height direction formed perpendicular to the protruding direction of the tab portion and the stacking direction in which the plurality of battery cells are stacked, the length of the flame retardant portion is 80% or more of the length of the body portion.

6. The battery assembly according to any one of claims 1 to 3, wherein Along the stacking direction in which the plurality of battery cells are stacked, the length of the flame retardant portion is equal to or less than the interval between the tab portions respectively provided in two adjacent battery cells among the plurality of battery cells.

7. The battery assembly according to any one of claims 1 to 3, wherein The flame retardant portion includes a head formed at one end, a bottom formed at the other end opposite to the one end, and a body portion connecting the head and the bottom, The head and the bottom have a shape in which the cross-sectional area decreases along a direction from the body portion toward their outermost sides.

8. The battery assembly according to claim 7, wherein The head and the bottom each include a flat surface formed perpendicular to the extending direction of the body portion.

9. The battery assembly according to claim 7, wherein The head and the bottom each have a conical shape in which one end including a vertex is cut.

10. The battery assembly according to claim 7, wherein The head has the same shape as the bottom.

11. The battery assembly according to claim 7, wherein The outer side surface of the body portion is formed as a curved surface.

12. The battery assembly according to claim 11, wherein The body portion is formed in a cylindrical shape.

13. The battery assembly according to claim 1, wherein The flame retardant part includes materials with a flame retardant rating of V0 or above according to the UL94 standard.

14. The battery assembly according to claim 13, wherein the flame retardant part includes flame retardant polyurethane.

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