Busbar frame assembly and battery module including same

Abstract

A bus bar frame assembly according to one embodiment of the present invention comprises: a bus bar connected to electrode leads of a plurality of battery cells; a printed circuit board (PCB) connected to the bus bar or the electrode leads so as to sense the voltage of the battery cells; and a bus bar frame on which the bus bar is arranged, wherein the bus bar frame includes a coupling part coupled to the bus bar, and the bus bar includes a recessed part coupled to the coupling part.

Description

Busbar frame assembly and battery module including the same

[0001] Cross-citation with related application(s)

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2024-0097118, filed July 23, 2024, the entire contents of which are incorporated herein by reference.

[0003] The present invention relates to a busbar frame assembly and a battery module including the same, and more particularly, to a busbar frame assembly and a battery module including the same, which can increase the degree of freedom in printed circuit board path design and reduce manufacturing costs.

[0004] In modern society, the widespread use of portable devices like cell phones, laptops, camcorders, and digital cameras has fueled active development of technologies related to these devices. Furthermore, rechargeable secondary batteries are increasingly being used as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (P-HEVs) to address air pollution caused by conventional gasoline-powered vehicles, further fueling the growing need for secondary battery development.

[0005] Currently commercialized secondary batteries include nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, and lithium secondary batteries. Among these, lithium secondary batteries are receiving attention for their advantages of being able to charge and discharge freely, having a very low self-discharge rate, and having a high energy density, as they have almost no memory effect compared to nickel-based secondary batteries.

[0006] These lithium secondary batteries primarily use lithium oxide and carbon materials as the positive and negative electrode active materials, respectively. The lithium secondary battery comprises an electrode assembly comprising a positive electrode plate and a negative electrode plate, each coated with the positive and negative electrode active materials, with a separator interposed between them, and a battery case that seals and houses the electrode assembly together with an electrolyte.

[0007] In general, lithium secondary batteries can be classified into can-type secondary batteries in which the electrode assembly is built into a metal can and pouch-type secondary batteries in which the electrode assembly is built into a pouch of an aluminum laminate sheet, depending on the shape of the outer packaging material.

[0008] Secondary batteries used in small devices are configured with 2-3 battery cells, but secondary batteries used in medium- to large-sized devices such as automobiles utilize battery modules in which multiple battery cells are electrically connected. These battery modules enhance capacity and output by forming a battery cell stack by connecting multiple battery cells in series or parallel. In addition, one or more battery modules may be mounted together with various control and protection systems, such as a Battery Disconnect Unit (BDU), a Battery Management System (BMS), and a cooling system, to form a battery pack.

[0009] Meanwhile, the battery pack is equipped with a bus bar connected to the battery module. A conventional bus bar is a metal member in the shape of a rod extending along the length direction, and a through hole may be formed at both ends of the bus bar for connection to the terminal bus bar of the battery module. This bus bar is a component that is responsible for the HV (High Voltage) connection in the battery pack. The HV connection refers to a connection that serves as a power source to supply power, and the bus bar is a component that guides the electrical connection of the battery module, and is typically made of a metal material with excellent electrical conductivity. For example, the bus bar may include a copper (Cu) material.

[0010] The busbars may be arranged in a busbar frame. The busbar frame is a member to prevent the electrode leads and busbars from coming into contact with other parts of the battery cell, thereby causing a short circuit, and may include an electrically insulating material.

[0011] The busbar can be secured to the busbar frame by a joint portion of the busbar frame. Conventional joints for securing the busbar protrude beyond one side of the busbar and are connected to the busbar. In this case, the protruding joint portion inevitably imposes significant restrictions on the design and layout of the welding plate and printed circuit board.

[0012] The problem to be solved by the present invention is to increase the degree of freedom in the design of a printed circuit board path, reduce the unit cost of a busbar frame assembly by unifying the shape of a welding plate, and specifically to provide a busbar frame assembly and a battery module including the same, which can reduce the possibility of defects in a printed circuit board.

[0013] However, the problems to be solved by the embodiments of the present invention are not limited to the problems described above and can be expanded in various ways within the scope of the technical ideas included in the present invention.

[0014] A busbar frame assembly according to one embodiment of the present invention comprises: a busbar connected to electrode leads of a plurality of battery cells; a printed circuit board (PCB) connected to the busbar or the electrode leads for voltage sensing of the battery cells; and a busbar frame on which the busbar is arranged; wherein the busbar frame includes a joining portion joined to the busbar, and the busbar includes a recessed portion joined to the joining portion.

[0015] The above-mentioned recessed portion may be located on one side of the bus bar.

[0016] Based on a direction perpendicular to one side of the busbar frame, the end of the joint may be lower in height than one side of the busbar where the busbar is connected to the electrode lead.

[0017] The end of the above-mentioned joint may not protrude beyond the above-mentioned surface of the bus bar.

[0018] A hook may be formed at the end of the above-mentioned joint.

[0019] The above hook can be coupled to the above recessed portion.

[0020] It may include at least one welding plate connecting the bus bar or the electrode lead and the printed circuit board.

[0021] The shapes of the above welding plates may all be the same.

[0022] At least a portion of the welding plate may be arranged to extend parallel to a portion extending from the printed circuit board toward the bus bar.

[0023] According to another embodiment of the present invention, a battery module including the busbar frame assembly is provided.

[0024] According to embodiments of the present invention, the degree of freedom in printed circuit board design can be improved, and the possibility of defects in the printed circuit board can be reduced.

[0025] The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

[0026] FIG. 1 is a perspective view showing a battery module according to one embodiment of the present invention.

[0027] FIG. 2 is a perspective view showing a busbar frame assembly included in the battery module of FIG. 1.

[0028] FIG. 3 is a plan view showing a busbar frame assembly included in the battery module of FIG. 1.

[0029] Fig. 4 is a plan view showing the busbar frame assembly of Fig. 3 viewed from a different angle.

[0030] FIG. 5 is a perspective view showing the busbar frame assembly of FIG. 2 with the printed circuit board and welding plate removed.

[0031] Figure 6 is an enlarged view showing the enlarged view of part “A” of Figure 5.

[0032] Figure 7 is a perspective view showing a bus bar according to one embodiment of the present invention.

[0033] Fig. 8 is a plan view showing the bus bar of Fig. 7.

[0034] Figure 9 is an enlarged view showing the enlarged view of part “B” of Figure 8.

[0035] Fig. 10 is a cross-sectional perspective view showing a cross-section taken along a cutting line passing through a busbar in the busbar frame assembly of Fig. 5.

[0036] Fig. 11 is a cross-sectional view showing Fig. 10 as viewed in the -X-axis direction.

[0037] Figure 12 is an enlarged view showing the enlarged view of the “C” portion of Figure 3.

[0038] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the invention. The present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0039] In order to clearly explain the present invention, parts that are not related to the description are omitted, and the same reference numerals are used for identical or similar components throughout the specification.

[0040] Furthermore, the sizes and thicknesses of each component shown in the drawings are arbitrarily indicated for convenience of explanation, and thus the present invention is not necessarily limited to the illustrated components. In the drawings, the thicknesses are enlarged to clearly represent various layers and regions. Furthermore, in the drawings, the thicknesses of some layers and regions are exaggerated for convenience of explanation.

[0041] Furthermore, when we say that a layer, membrane, region, plate, or other part is "on" or "over" another part, this includes not only cases where it is "directly on" the other part, but also cases where there are other parts in between. Conversely, when we say that a part is "directly on" another part, we mean that there are no other parts in between. Furthermore, saying that a part is "on" or "over" a reference part means that it is located above or below the reference part, and does not necessarily mean that it is located "above" or "over" the reference part in the opposite direction of gravity.

[0042] Additionally, throughout the specification, whenever a part is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise specifically stated.

[0043] Additionally, throughout the specification, when we say "in plan", we mean when the target portion is viewed from above, and when we say "in cross section", we mean when the target portion is viewed from the side in a cross-section cut vertically.

[0044] FIG. 1 is a perspective view showing a battery module (100) according to one embodiment of the present invention. FIG. 2 is a perspective view showing a busbar frame assembly (150) included in the battery module of FIG. 1. FIG. 3 is a plan view showing a busbar frame assembly (150) included in the battery module of FIG. 1. FIG. 4 is a plan view showing the busbar frame assembly (150) of FIG. 3 from a different angle. FIG. 5 is a perspective view showing the busbar frame assembly (150) of FIG. 2 with a printed circuit board and a welding plate (154) removed. FIG. 6 is an enlarged view showing an enlarged view of part “A” of FIG. 5. FIG. 7 is a perspective view showing a busbar (152) according to one embodiment of the present invention. FIG. 8 is a plan view showing the busbar (152) of FIG. 7. FIG. 9 is an enlarged view showing an enlarged view of part “B” of FIG. Fig. 10 is a cross-sectional perspective view showing a cross-section taken along a cutting line passing through a busbar (152) in the busbar frame assembly of Fig. 5. Fig. 11 is a cross-sectional view showing Fig. 10 as viewed in the -X-axis direction.

[0045] Referring to FIGS. 1 to 11, a busbar frame assembly (150) according to one embodiment of the present invention includes a busbar (152) connected to electrode leads (111) of a plurality of battery cells (110); a printed circuit board (153) connected to the busbar (152) or the electrode leads (111) for voltage sensing of the battery cells (110); and a busbar frame (151) on which the busbar (152) is arranged. The busbar frame (151) includes a coupling portion (151a) coupled to the busbar (152), and the busbar (152) includes a recessed portion (152a) coupled to the coupling portion (151a).

[0046] The battery module (100) according to the present embodiment may include a plurality of battery cells (110). The battery cell (110) according to the present embodiment may be a battery cell (110) of various shapes, for example, a pouch-shaped battery cell, a square battery cell, or a cylindrical battery cell. For example, as illustrated in FIG. 1, the battery cell (110) according to the present embodiment may be a pouch-shaped battery cell (110). Hereinafter, the pouch-shaped battery cell (110) will be described, but the battery cell according to the present embodiment is not limited thereto, and various types of battery cells may be applied.

[0047] A plurality of battery cells (110) may be provided within the battery module (100). For example, a plurality of battery cells (110) may be stacked along one direction so as to be electrically connected to each other to form a battery cell stack (120). For example, a plurality of battery cells (110) may be stacked along a direction parallel to the X-axis while standing upright. The battery cells (110) may be stacked from one side of the module frame (130) to the other side in a state where one side of the battery cells (110) is parallel to the side surfaces of the module frame (130). Accordingly, the electrode leads (111) may protrude in a direction perpendicular to the direction in which the battery cells (110) are stacked. In the battery cell (110), one electrode lead (111) may protrude toward the +Y-axis direction, and the other electrode lead (111) may protrude toward the -Y-axis direction. If the battery cell (110) has electrode leads (111) protruding in only one direction, the electrode leads (111) may protrude in the +Y-axis direction or the -Y-axis direction.

[0048] The module frame (130) may be a U-shaped frame with open top, front, and back surfaces. However, the module frame (130) is not limited thereto, and may be replaced with a frame of another shape, such as an L-shaped frame or a mono-frame that surrounds the battery cell stack (120) except for the front and back surfaces. That is, the module frame of another embodiment may be formed as an integral module frame that is not separated into a U-shaped frame and a top plate.

[0049] For example, the module frame (130) may include a bottom portion and two side portions. The two side portions may extend upward from opposite sides of the bottom portion in a direction perpendicular to one side of the bottom portion. The bottom portion and the two side portions may cover the lower surface and both side surfaces of the battery cell stack (120). One side of the battery cells (110) in the battery cell stack (120) is parallel to the side surfaces of the module frame (130), and the battery cells (110) may be stacked along a direction from one side of the module frame (130) to the other side of the module frame (130).

[0050] The top cover (140) can cover the upper portion of the battery cells (110). The battery cells (110) can be stored in a space formed by the module frame (130) and the top cover (140). The module frame (130) and the top cover (140) are joined to each other by a method such as welding at corresponding corners, so that the module frame (130) can cover the upper portion, lower portion, and both sides of the battery cell stack (120).

[0051] According to the present embodiment, the busbar frame assemblies (150) may be formed to cover the battery cell stack (120) by being positioned on the open first side (Y-axis direction of FIG. 1) and second side (-Y-axis direction of FIG. 1) of the module frame (130). In other words, the busbar frame assemblies (150) may be positioned to cover the first side and the second side in the direction in which the electrode leads (111) protrude in the battery cell stack (120). The busbar frame assemblies (150) may electrically connect the battery cells (110) included in the battery cell stack (120) in series or in parallel.

[0052] The busbar frame assembly (150) may include a busbar frame (151) on which busbars (152) are arranged. The busbar frame (151) is a member for preventing the electrode leads (111) and the busbars (152) from coming into contact with other parts of the battery cells (110) and causing a short circuit, and may include an electrically insulating material. In addition, the busbar frame assembly (150) may include at least one busbar (152) connected to the electrode leads (111). Specifically, at least one busbar (152) may be mounted on one surface of the busbar frame (151), and the other surface of the busbar frame (151) may face the battery cell stack (120). In other words, in the busbar frame (151), a portion where the busbars (152) are mounted and a portion facing the battery cell stack (120) may be located on opposite surfaces. The electrode lead (111) protruding from the battery cell (110) can pass through a slit formed in the bus bar frame (151) and then be connected to the bus bar (152).

[0053] According to the present embodiment, the electrode leads (111) connected to the electrode assembly protrude outside the pouch case, and the electrode leads (111) of each battery cell (110) can be electrically connected to each other via a bus bar (152). The bus bar (152) is configured to guide electrical connection between battery cells (110) within the battery module (100) or to guide electrical connection of the battery module (100). The bus bar (152) may be made of a metal material having excellent electrical conductivity, and is not limited in shape or material.

[0054] According to the present embodiment, the printed circuit board (153) is provided to sense voltage data or thermal data of the battery cells (110). For example, the printed circuit board (153) may be connected to the electrode leads (111) or bus bars (152) of the battery cells (110). Accordingly, the voltage data of each battery cell (110) may be sensed and transmitted to the BMS (Battery Management System). The BMS may control the operation of the battery module (100) based on the voltage data of the battery cells (110) included in the battery module (100).

[0055] The printed circuit board (153) may be a flexible printed circuit board. The printed circuit board (153) is provided to extend in the longitudinal direction of the battery cells (110) and be mounted so as to sense the battery cells (110). In particular, the printed circuit board (153), which is a flexible printed circuit board, may be bent and electrically connected to the electrode leads (111) or bus bars (152) of the battery cells (110). Accordingly, voltage data of each battery cell (110) may be sensed and transmitted to the outside.

[0056] Meanwhile, the busbar frame assembly (150) may further include a busbar frame assembly cover (160) that covers the busbar frame assembly (150). Specifically, the busbar frame assembly cover (160) may cover one surface of the busbar frame (151) on which the busbar (152) is mounted. The busbar frame assembly cover (160) may cover and insulate a plurality of busbars (152) for electrical connection of battery cells (110), terminals (not shown) of the battery module (100), and electrode leads (111) to protect them from the outside. In addition, it may prevent disassembly of the battery module (100) by unspecified persons other than the manager.

[0057] Although not shown, the busbar frame assembly cover (160) can be detachably connected to the busbar frame (151) by a hook structure. By the hook structure, the busbar frame assembly cover (160) can be fixed to the correct position of the busbar frame (151), and can be easily assembled and disassembled in a one-touch manner.

[0058] Although not shown, in order to prevent the busbar frame assembly cover (160) from moving, a rib structure of a predetermined shape may be provided on the inner wall of the busbar frame (151).

[0059] Referring again to FIGS. 7 to 11, the recessed portion (152a) according to the present embodiment may be located on one side of the bus bar (152).

[0060] Specifically, the recessed portion (152a) may be located on one side where the bus bar (152) is physically connected to the bus bar frame (151). The recessed portion (152a) may have a recessed shape on the side of the bus bar (152).

[0061] As the recessed portion (152a) is positioned on one side of the bus bar (152), the connecting portion (151a) of the bus bar frame (151) can also be positioned corresponding to one side of the bus bar (152). Through this, the connecting portion (151a) can be designed so as not to protrude beyond one side of the bus bar (152) in the -Y-axis direction of FIG. 10. As will be described later, since the connecting portion (151a) does not protrude beyond one side of the bus bar (152), the degree of freedom in designing the path of the printed circuit board (153) can be increased. In addition, since design constraints on the arrangement direction of the welding plate (154) are reduced, the degree of freedom in designing the welding plate (154) can be increased, and the unit cost of the bus bar frame assembly (150) can be reduced through component integration of the welding plate (154).

[0062] Referring again to FIGS. 6, 10, and 11, with respect to a direction perpendicular to one side of the busbar frame (151), the end of the connecting portion (151a) may be lower in height than one side of the busbar (152) where the busbar (152) is connected to the electrode lead (111). Here, one side of the busbar (152) where the busbar (152) is connected to the electrode lead (111) may be the opposite side of the side where the busbar (152) faces the busbar frame (151).

[0063] Specifically, in FIG. 11, the left side of the bus bar (152) may be a side that is joined to the electrode lead (111). The end of the connecting portion (151a) may not protrude beyond the above-mentioned side of the bus bar (152) in the -Y-axis direction of FIG. 11. Conventionally, a conventional connecting portion for fixing a bus bar protrudes beyond the above-mentioned side of the bus bar and is connected to the bus bar. In this case, the design and arrangement of the welding plate and the printed circuit board are inevitably restricted due to the protruding connecting portion. However, as in the present embodiment, since the end of the connecting portion (151a) does not protrude beyond the above-mentioned side of the bus bar (152), the degree of freedom in the path design of the printed circuit board (153) can be increased. In addition, the design constraints on the arrangement direction of the welding plate (154) can be reduced, thereby increasing the degree of freedom in designing the welding plate (154), and the unit cost of the busbar frame assembly (150) can be reduced through the unification of the parts of the welding plate (154).

[0064] Referring again to FIGS. 6, 10, and 11, the end of the connecting portion (151a) may not protrude beyond one surface of the bus bar (152).

[0065] Specifically, in Fig. 11, the end of the connecting portion (151a) may not protrude beyond one side of the bus bar (152) in the -Y-axis direction of Fig. 11. This allows for avoiding interference between the connecting portion (151a) and components corresponding to or in contact with the bus bar (152). Accordingly, events such as internal short circuits can be prevented.

[0066] Referring again to FIGS. 6, 10, and 11, a hook (151aa) may be formed at the end of the connecting portion (151a).

[0067] The connecting portion (151a) can be detachably connected to the bus bar (152) by means of a hook (151aa) formed at the end of the connecting portion (151a). By means of the hook (151aa) of the connecting portion (151a), the bus bar (152) can be fixed to the correct position of the bus bar frame (151), and can be easily assembled and disassembled in a one-touch manner.

[0068] Referring again to FIGS. 6, 10, and 11, the hook (151aa) can be coupled to the recessed portion (152a). The coupling portion (151a) can be detachably coupled to the recessed portion (152a) of the bus bar (152) by the hook (151aa) formed at the end of the coupling portion (151a). As described above, the bus bar (152) can be fixed to the correct position of the bus bar frame (151) by the hook (151aa) of the coupling portion (151a), and can be easily assembled and disassembled in a one-touch manner.

[0069] Figure 12 is an enlarged view showing the enlarged view of the “C” portion of Figure 3.

[0070] Referring to FIG. 12, the busbar frame assembly (150) according to the present embodiment may include at least one welding plate (154) connecting the busbar (152) or electrode lead (111) and the printed circuit board (153).

[0071] A welding plate (154) can be connected to a bus bar (152), and the welding plate (154) can be connected to a printed circuit board (153). As a result, the bus bar (152) and the printed circuit board (153) can be electrically connected using the welding plate (154) as a medium.

[0072] The welding plate (154) may include nickel or a nickel alloy having relatively excellent weldability. The welding plate (154) and the bus bar (152), and the welding plate (154) and the printed circuit board (153) may be structured to be joined to each other by laser welding. Generally, laser welding is welding using a high-energy laser beam, and can enable fine welding.

[0073] Referring again to FIG. 12, the shapes of the welding plates (154) may all be identical. Since the shapes of the welding plates (154) are identical, the component integration of the welding plates (154) may be possible. This may reduce the unit cost of the busbar frame assembly (150).

[0074] Referring again to FIG. 12, at least a portion of the welding plate (154) may be positioned to extend parallel to a portion extending from the printed circuit board (153) toward the bus bar (152).

[0075] Specifically, at least a portion of the welding plate (154) may be arranged to extend parallel to a portion extending from the printed circuit board (153) toward the bus bar (152), such as the welding plate (154) of FIG. 12 (in the -Z-axis direction of FIG. 12).

[0076] Another part of the welding plate (154) may be arranged to extend perpendicularly (in the -X-axis direction of FIG. 12) to the part extending from the printed circuit board (153) toward the bus bar (152), such as the welding plate (154) of FIG. 12.

[0077] As described above, since the recessed portion (152a) is located on one side of the bus bar (152) and the end of the connecting portion (151a) does not protrude beyond the one side of the bus bar (152), the design constraints on the arrangement direction of the welding plate (154) are reduced. That is, the degree of freedom in design can be increased compared to the conventional bus bar frame assembly (150) in which the connecting portion (151a) protrudes beyond one side of the bus bar (152) and is connected to the bus bar (152). The arrangement, direction, shape, etc. of the welding plate (154) can be determined depending on the arrangement of the bus bar (152), the shape of the printed circuit board (153), etc.

[0078] Referring again to FIG. 1, according to another embodiment of the present invention, a battery module (100) including a busbar frame assembly (150) is provided.

[0079] Although the application of pouch-type battery cells (110) to the battery module (100) has been described as an example, square battery cells (110) or cylindrical battery cells (110) may also be applied to the battery module (100) according to an embodiment of the present invention. In addition, although the battery module (100) in which the battery cells (110) are housed in the module frame (130) has been described as an example, a CTP (cell to pack) type battery module (100) in which a plurality of battery cells (110) are mounted in a battery pack without being housed in the module frame (130) may also be applied as an example of the present invention.

[0080] In this example, terms indicating directions such as front, back, left, right, up, and down are used, but these terms are only for convenience of explanation and may vary depending on the location of the target object or the location of the observer.

[0081] Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims also fall within the scope of the present invention.

[0082] Description of the symbol

[0083] 100: Battery module

[0084] 110: Battery cell

[0085] 120: Battery cell stack

[0086] 130: Module Frame

[0087] 150: Busbar frame assembly

[0088] 151: Busbar frame

[0089] 151a: Joint

[0090] 152: Busbar

[0091] 152a: Depression

[0092] 153: Printed circuit board

[0093] 154: Welding plate

Claims

1. A bus bar connected to the electrode leads of multiple battery cells; A printed circuit board (PCB) connected to the bus bar or the electrode lead for voltage sensing of the battery cells; and including a busbar frame in which the above busbar is arranged; The above busbar frame includes a joint that is coupled to the above busbar, A busbar frame assembly, wherein the busbar includes a recessed portion that is coupled to the coupling portion.

2. In paragraph 1, A busbar frame assembly, wherein the above-mentioned recessed portion is located on one side of the busbar.

3. In paragraph 1, A busbar frame assembly, wherein, based on a direction perpendicular to one side of the busbar frame, an end of the joint portion is lower in height than one side of the busbar where the busbar is connected to the electrode lead.

4. In paragraph 1, A busbar frame assembly in which the end of the above-mentioned joint does not protrude beyond the above-mentioned surface of the busbar.

5. In paragraph 1, A busbar frame assembly having a hook formed at the end of the above-mentioned joint.

6. In paragraph 5, A busbar frame assembly wherein the above hook is coupled to the above recessed portion.

7. In paragraph 1, A busbar frame assembly comprising at least one welding plate connecting the busbar or the electrode lead and the printed circuit board.

8. In paragraph 7, The shape of the above welding plates is all the same, busbar frame assembly.

9. In paragraph 7, A busbar frame assembly, wherein at least a portion of the welding plate is positioned to extend parallel to a portion extending from the printed circuit board toward the busbar.

10. A battery module comprising a busbar frame assembly according to paragraph 1.

Images