Lower cover plate for single battery, shell component and single battery

Abstract

The utility model belongs to the field of batteries, and particularly relates to a lower cover plate for a single battery, a shell component and the single battery. The lower cover plate comprises a lower cover plate main body and a sealing mechanism arranged on the lower cover plate main body; a sunken part which is sunken towards the inner cavity of the single battery is arranged in a partial region of the lower cover plate main body; the sealing mechanism is arranged in the sunken part. When the single battery is placed, the non-concave area serves as the supporting part of the single battery, the concave part and the sealing mechanism located in the concave part have a certain distance from the placing area, the non-concave flatness is not affected, and then it can be ensured that the single battery is stably placed.

Description

Technical Field

[0001] The utility model belongs to the field of batteries, and in particular relates to a lower cover plate for a single cell battery, a shell component and a single cell battery. Background Art

[0002] Currently, many single cells are connected in parallel or in series on the market to form large-capacity batteries (also called battery modules or battery packs).

[0003] However, the individual cells in existing large-capacity batteries are different from each other. Due to the existence of the barrel effect, they are often affected by the cell with the worst performance, which greatly limits the capacity limit and cycle times of the entire large-capacity battery. Therefore, how to improve the uniformity of each cell in a large-capacity battery has become the focus and difficulty of research in this field.

[0004] In order to solve the above problems, Chinese patent CN220324596U discloses a large-capacity battery, the structure of which is as follows Figure 1 As shown, this type of large-capacity battery includes a housing 01 and multiple single cells 001, and the multiple single cells 001 are connected in parallel in sequence and arranged in the inner cavity of the housing 01; the housing 01 is provided with a shared chamber (the shared chamber described here is an electrolyte shared chamber 02 and / or a gas shared chamber 03), and the shared chamber is connected to the inner cavity of each single cell. The electrolyte and / or gas in the inner cavity of each single cell are connected through the electrolyte shared chamber and / or the gas shared chamber, respectively, so that the electrolyte and / or gas of all single cells are in the same system, reducing the differences between the single cells, and improving the consistency between the single cells to a certain extent, thereby improving the cycle life of the large-capacity battery to a certain extent.

[0005] Usually, the package can be opened by opening a sealing mechanism fixed at a weak area of ​​the single battery shell or sealed at an opening position, thereby achieving communication between the shared chamber and the inner cavities of all single batteries.

[0006] Specifically, the sealing mechanism disclosed in Chinese patent CN220324512U can be used, and its structure is as follows: Figure 2 As shown, the packing opening device is used to penetrate the traction ring 32 of the sealing mechanism, and the packing opening device is pushed to separate the sealing mechanism from the weak portion 31 of the single battery; the sealing mechanism disclosed in Chinese patent CN219658820U can also be used, and its structure is as shown in Figure 3 As shown, such a sealing mechanism includes a sealing sheet that can dissolve in electrolyte, and the surface of the dissolving sheet facing the inner cavity of the single battery housing is coated with a metal coating that is insoluble in electrolyte. The sealing mechanism can be separated from the single battery by external electrolyte (electrolyte outside the single battery).

[0007] By adopting the above sealing mechanism and the corresponding unpacking method, the shared chamber can be connected with the inner chambers of all the single cells smoothly. Figure 2 and Figure 3 It can be seen that the sealing mechanisms in the above patents all protrude from the lower cover plate of the single cell, which will cause the single cell with such sealing mechanism to be unable to be placed stably, making it difficult to store or transport. Utility Model Content

[0008] The utility model aims to provide a lower cover plate for a single cell, a shell component and a single cell, which overcomes the technical problem that the single cell cannot be placed stably because the sealing mechanism protrudes from the lower cover plate of the single cell.

[0009] The technical solution of the utility model is to provide a lower cover plate for a single cell battery, comprising a lower cover plate body and a sealing mechanism arranged on the lower cover plate body; the special feature is that a part of the lower cover plate body is provided with a recessed portion recessed into the inner cavity of the single cell battery, and the sealing mechanism is arranged in the recessed portion.

[0010] The utility model provides a recessed portion in a partial area of ​​the lower cover plate and fixes the sealing mechanism in the recessed portion. When placing a single battery, the non-recessed area serves as a supporting portion for the single battery. That is, when the single battery is placed, only the non-recessed area is in contact with the placement area (the placement area here is the placement area of ​​the single battery), and the recessed portion and the sealing mechanism located in the recessed portion are both at a certain distance from the placement area, so as not to affect the flatness of the non-recessed area, thereby ensuring that the single battery is placed stably.

[0011] Furthermore, the utility model can adopt at least the following three solutions to set a recessed portion on a partial area of ​​the lower cover:

[0012] Solution 1: Use a conventional flat lower cover body, set an annular boss on the lower cover body, the annular boss protrudes away from the inner cavity of the single cell, and the area enclosed by the annular boss is used as the recessed portion. That is, in this solution, the annular boss is used as a non-recessed area, which is in contact with the placement area, to ensure that the single cell is placed stably.

[0013] In this solution, the annular boss is arranged along the four edges of the lower cover body, which can maximize the contact area between the non-recessed area and the placement area, further improving the stability of the single battery when placed. The above-mentioned annular boss can be an integral part with the lower cover body. A notch can also be provided on the annular boss at a position opposite to the sealing mechanism, and the package opening device cooperates with the sealing mechanism through the notch to achieve package opening.

[0014] Solution 2: This solution also uses a conventional flat lower cover body, and a blind hole recessed into the inner cavity of the single battery is provided in a part of the lower cover body as the recessed portion. In this solution, the area of ​​the lower cover body without the blind hole is used as the single battery support portion, which can ensure that the single battery is placed stably. Compared with Solution 1, this solution requires a thicker lower cover body.

[0015] Solution 3: Different from the above two solutions, in this solution, the main body of the lower cover is a curved plate, and part of the lower cover main body is recessed into the inner cavity of the single battery to form the recessed portion. That is, in this solution, the non-recessed area of ​​the curved plate is used as the single battery support portion, which is in contact with the placement area, and can ensure that the single battery is placed stably.

[0016] On the other hand, the utility model further provides a shell component, characterized in that it includes a cylinder and a lower cover plate fixed to any open end of the cylinder, wherein the lower cover plate is the above-mentioned lower cover plate for the single cell.

[0017] In a third aspect, the utility model further provides a single cell battery, characterized in that it comprises the above-mentioned shell component.

[0018] The beneficial effects of the utility model are:

[0019] The utility model provides a recessed portion in a partial area of ​​the lower cover plate and fixes the sealing mechanism in the recessed portion. When placing a single battery, the non-recessed area serves as a supporting portion for the single battery. That is, when the single battery is placed, only the non-recessed area is in contact with the placement area (the placement area here is the placement area of ​​the single battery), and the recessed portion and the sealing mechanism located in the recessed portion are both at a certain distance from the placement area, so as not to affect the flatness of the non-recessed area, thereby ensuring that the single battery is placed stably. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of a local explosion structure of a large-capacity battery in the background technology;

[0021] Figure 2 It is a structural schematic diagram of a single battery in the background technology;

[0022] Figure 3 is a schematic structural diagram of another single battery in the background technology;

[0023] Figure 4 This is a schematic structural diagram of a lower cover plate for a single cell in Example 1;

[0024] Figure 5 It is a schematic diagram of another structure of a lower cover plate for a single cell;

[0025] Figure 6 It is a schematic diagram of the structure of the third type of lower cover plate for a single cell;

[0026] Figure 7 is a schematic structural diagram of the shell component in Example 1;

[0027] Figure 8 The structure of the single cell in Example 1 is shown in FIG. Figure 1 ;

[0028] Fig. 9 The structure of the single cell in Example 1 is shown in FIG. Figure 2 ;

[0029] Fig.10 This is a schematic structural diagram of a lower cover plate for a single cell in Example 2;

[0030] Fig.11 is a schematic structural diagram of a shell component in Example 2;

[0031] Fig.12 The structure of the single cell in Example 2 is shown in FIG. Figure 1 ;

[0032] Fig.13 The structure of the single cell in Example 2 is shown in FIG. Figure 2 ;

[0033] Fig.14 This is a schematic structural diagram of a lower cover plate for a single cell in Example 3;

[0034] Fig.15 is a schematic structural diagram of a shell component in Example 3;

[0035] Fig.16 The structure of the single cell in Example 3 is shown in FIG. Figure 1 ;

[0036] Fig.17 The structure of the single cell in Example 3 is shown in FIG. Figure 2 .

[0037] The accompanying drawings in the figure are marked as follows:

[0038] 001, single cell; 01, outer shell; 02, electrolyte shared chamber; 03, gas shared chamber;

[0039] 2. Lower cover plate; 3. Sealing mechanism; 31. Weak part; 32. Traction ring; 5. Protrusion; 51. Notch; 6. Recessed part; 7. Cylinder; 8. Non-recessed area; 9. Support rib plate. DETAILED DESCRIPTION

[0040] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the utility model, but not all of them. Based on the embodiments of the utility model, all other embodiments obtained by ordinary persons in the field without creative work should fall within the scope of protection of the utility model.

[0041] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0042] In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "top, bottom" etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0043] The utility model discloses a lower cover plate for a single cell battery, comprising a lower cover plate body and a sealing mechanism arranged on the lower cover plate body; different from the lower cover plate for a single cell battery disclosed in the background technology, the utility model is provided with a recessed portion recessed into the inner cavity of the single cell battery in a partial area of ​​the lower cover plate body, and the sealing mechanism is arranged in the recessed portion.

[0044] It should be noted here that:

[0045] 1. The single cell battery described here is a square shell battery, including an upper cover plate, a lower cover plate, a cylinder, a battery cell assembly and an electrolyte; the upper cover plate or the lower cover plate and the cylinder can be integrally formed. The upper cover plate, the cylinder and the lower cover plate constitute the shell of the single cell battery, and the battery cell assembly and the electrolyte are located in the shell of the single cell battery.

[0046] 2. In the present utility model, the above-mentioned battery cell assembly can be referred to as an electrode assembly, which is composed of a positive electrode, a separator, and a negative electrode arranged in sequence and assembled by a lamination or winding process. It should be emphasized that the above-mentioned battery cell assembly can also be a commercially available square shell battery with a through hole in the shell. If the battery cell assembly is a commercially available square shell battery with a through hole in the shell, the above-mentioned sealing mechanism needs to correspond to the through hole, and when the sealing mechanism is opened, the opening formed on the shell should be connected with the through hole in the shell.

[0047] 3. The above-mentioned lower cover body part area can be located in the central area of ​​the lower cover body, and can also be located in any area other than the central area; in addition, the lower cover body part area can be a continuous area, and can also be a plurality of discontinuous areas; when the lower cover body part area is a continuous area, at least one recessed portion can be set on the continuous area; when the lower cover body part area is a plurality of discontinuous areas, a recessed portion can be set in each area.

[0048] 4. The above-mentioned "a recessed portion recessed into the inner cavity of the single battery cell is provided in a partial area of ​​the lower cover body" can be achieved through a variety of solutions. For example, protrusions can be provided on the flat lower cover body. Relative to the protrusions, the area between the protrusions can be regarded as the recessed portion; the lower cover body can also be directly designed as a curved plate recessed into the inner cavity of the single battery cell, for example, it can be an arc-shaped plate, etc.; in addition, blind holes can be directly dug on the flat lower cover body to form the recessed portion. Compared with other solutions, this solution requires the lower cover body to have a thicker thickness.

[0049] 5. The above-mentioned “the sealing mechanism is disposed in the recessed portion” means that all parts of the sealing mechanism are located in the recessed portion; if the length direction of the single cell is defined as the x direction, the width direction of the single cell is defined as the y direction, and the height direction of the single cell is defined as the z direction, then on the yz plane, the orthographic projection of the lower cover body should completely cover the orthographic projection of the sealing mechanism.

[0050] The utility model also discloses a shell component, which comprises a cylinder and the above-mentioned lower cover plate for the single battery.

[0051] The utility model also discloses a single cell having the above-mentioned shell member. The utility model sets a recessed portion in a part of the lower cover plate and fixes the sealing mechanism in the recessed portion. When the single cell is placed, the non-recessed area serves as a supporting portion of the single cell, that is, when the single cell is placed, only the non-recessed area is in contact with the placement area (the placement area here is the placement area of ​​the single cell), and the recessed portion and the sealing mechanism in the recessed portion are at a certain distance from the placement area, which does not affect the flatness of the non-recessed portion, thereby ensuring that the single cell is placed stably.

[0052] The single cell provided by the utility model is mainly used to construct a large-capacity battery, such as the large-capacity battery described in the background technology Chinese patent CN220324596U, and can also be used to construct a large-capacity battery disclosed in Chinese patents CN117477063A, CN117477186A, and CN115275453A.

[0053] Such a large-capacity battery comprises at least a plurality of single cells and at least one electrolyte sharing chamber;

[0054] The electrolyte shared chamber described here is the electrolyte shared chamber described in CN220324596U, the first hollow component described in CN117477186A, and the electrolyte shared channel described in CN115275453A.

[0055] After the large-capacity battery is initially constructed, the sealing mechanism is opened using an external electrolyte (which can be understood as the electrolyte in the electrolyte sharing chamber) or a package opening device, and an opening is formed in the lower cover body. The electrolytes in the inner cavities of each single cell are connected through the electrolyte sharing chamber, so that the electrolytes of all single cells are in the same system, reducing the differences between the electrolytes of each single cell, improving the consistency between the single cells to a certain extent, and thus improving the cycle life of the large-capacity battery to a certain extent.

[0056] It should be noted that if the sealing mechanism disclosed in Chinese patent CN220324512U or a sealing mechanism similar thereto with a traction part or a traction ring is used, when using it to construct a large-capacity battery, it is necessary to stretch the traction part or the traction ring so that the traction part or the traction ring exposes the recessed part, so as to cooperate with the package opening device to open the package. A notch can also be opened in the non-recessed area corresponding to the traction part or the traction ring, so that the package opening device cooperates with the traction part or the traction ring through the notch to open the package.

[0057] The lower cover plate with different recessed parts, the corresponding shell member and the single battery are described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0058] Example 1

[0059] like Figure 4 As shown in FIG. 1 , it is a schematic structural diagram of the lower cover plate 2 for the single cell in this embodiment. As can be seen from the figure, this embodiment uses a flat lower cover plate body, on which a protrusion 5 protruding away from the inner cavity of the single cell is provided, and the lower cover plate body area without the protrusion 5 is regarded as a recessed portion 6, and the sealing mechanism 3 is fixed in the recessed portion 6. The protrusion 5 is used as a single cell supporting portion and is in contact with the placement area, so that the single cell can be placed stably.

[0060] The protrusions 5 may be at least two long strip-shaped supporting ribs 9 provided on the lower cover body. Preferably, the two long strip-shaped supporting ribs 9 are symmetrical with respect to the sealing mechanism 3. Figure 5 The protrusion 5 can also be an annular boss, and the area enclosed by the annular boss is used as the recessed portion 6, as shown in FIG. Figure 4 and Figure 6 shown.

[0061] In order to further improve the support stability of the single battery, Figure 4It can be seen that in this embodiment, an annular boss is arranged along the four edges of the flat lower cover body (the annular boss has the largest contact area with the placement area), and the sealing mechanism 3 is located in the area enclosed by the annular boss. In order to ensure that the sealing mechanism 3 does not expose the area enclosed by the annular boss, this embodiment limits the size of the annular boss in the z direction. In the z direction, the size of the annular boss is greater than the maximum size of the sealing mechanism 3.

[0062] It should be noted that the dimension of the annular boss in the z direction should not be too large, as long as it is slightly larger than the maximum dimension of the sealing mechanism 3, so as to avoid the dimension being too large, which will lead to the entire single cell being too large, thereby affecting the energy density after it is assembled into an energy storage device.

[0063] In this embodiment, the annular boss and the lower cover plate body are an integral part and can be integrally formed by a die-casting process.

[0064] In other embodiments, the annular boss and the lower cover body may be separate parts, and the annular boss and the lower cover body may be fixed to the lower cover body by welding.

[0065] like Figure 7 As shown, a shell structure having the above-mentioned lower cover plate 2 for a single cell includes a cylinder 7 and the lower cover plate 2 fixed to any open end of the cylinder 7 .

[0066] like Figure 8 As shown, a single cell having the above-mentioned shell structure is used. When the single cell leaves the factory, is stored or transported, the protrusion 5 is used as a supporting portion for the single cell. Since the sealing mechanism 3 is located in the recessed portion 6, the lower end surface of the entire protrusion 5 is located in the same plane, so that the single cell can be placed stably.

[0067] by Fig. 9 For example, it should be noted that if the sealing mechanism disclosed in Chinese patent CN220324512U or a similar sealing mechanism with a traction part or a traction ring is used, when using it to build a large-capacity battery, it is necessary to stretch the traction part or the traction ring so that the traction part or the traction ring exposes the recessed part, so as to cooperate with the opening device to achieve opening the package.

[0068] Or you can also use Fig. 9 In the manner shown, a notch 51 is provided in the area of ​​the protrusion 5 corresponding to the traction portion or the traction ring 32, so that the packing opening device can cooperate with the traction portion or the traction ring through the notch (at this time, the corresponding traction ring 32 should be flipped up in the direction away from the weak portion 31 to facilitate cooperation with the packing opening device, but in the z direction, the overall size of the sealing mechanism is still smaller than the size of the protrusion 5, thereby still being able to achieve stable placement of the single battery) to achieve packing opening.

[0069] Example 2

[0070] like Fig.10 , which is a schematic diagram of the structure of the lower cover plate 2 for a single cell in this embodiment. Different from the embodiment 1, this embodiment has a blind hole in the main part of the lower cover plate as the recessed part 6, and the sealing mechanism 3 is fixed in the recessed part 6. In this embodiment, the main part of the lower cover plate without the blind hole is regarded as a single cell supporting part, which is in contact with the placement area, and can ensure that the single cell is placed stably.

[0071] The present embodiment does not specifically limit the shape of the blind hole, as long as its inner cavity can accommodate the sealing mechanism 3. For example, it can be Fig.10 The straight blind hole shown can also be used Fig.13 As shown, the hemispherical blind hole (the inner wall of the blind hole is a smooth hemispherical surface).

[0072] In order to ensure that the sealing mechanism 3 does not expose the blind hole, the embodiment limits the size of the blind hole in the z direction (the depth of the blind hole). In the z direction, the size of the blind hole is larger than the maximum size of the sealing mechanism 3 .

[0073] It should be noted that the size of the blind hole in the z direction should not be too large, as long as it is slightly larger than the maximum size of the sealing mechanism 3, so as to avoid excessive size, which will lead to a thicker thickness of the entire lower cover 2, and then lead to excessive size of the single battery, which will affect the energy density after it is assembled into an energy storage device.

[0074] like Fig.11 As shown, a shell structure having the above-mentioned lower cover plate 2 for a single cell includes a cylinder 7 and the lower cover plate 2 fixed to any open end of the cylinder 7 .

[0075] like Fig.12 As shown, a single cell having the above-mentioned shell structure is provided. During the process of leaving the factory, storage or transportation of the single cell, the main body area of ​​the lower cover plate without a blind hole is used as a supporting part of the single cell. Since the sealing mechanism 3 is located in the blind hole, the entire main body area of ​​the lower cover plate without a blind hole is located in the same plane, so that the single cell can be placed stably.

[0076] It should be noted that if the sealing mechanism disclosed in Chinese patent CN220324512U or a similar sealing mechanism with a traction part or a traction ring is used, when using it to build a large-capacity battery, it is necessary to stretch the traction part or the traction ring so that the traction part or the traction ring exposes the blind hole, so as to cooperate with the opening device to achieve opening.

[0077] Example 3

[0078] like Fig.14As shown, it is a schematic diagram of the structure of the lower cover plate 2 for the single cell battery of this embodiment. Different from the above-mentioned embodiment, this embodiment uses a curved plate as the main body of the lower cover plate, and a part of the curved plate is recessed into the inner cavity of the single cell. The recessed portion is regarded as a recessed portion 6, and the sealing mechanism 3 is fixed in the recessed portion 6. The remaining area (non-recessed area 8) except the recessed area is used as a single cell support portion, which is in contact with the placement area, thereby ensuring that the single cell is placed stably.

[0079] The curved panel can be made of a variety of structures. In order to simplify the structure, this embodiment uses the following Fig.14 The arc-shaped plate shown; the sealing mechanism 3 is fixed at the center position of the arc-shaped plate.

[0080] In order to ensure that the sealing mechanism 3 does not expose the recessed portion 6 , the embodiment limits the size of the curved plate in the z direction. In the z direction, the recessed depth of the recessed portion 6 should be greater than the maximum size of the sealing mechanism 3 .

[0081] It should also be noted that the depth of the concave arc plate should not be too large, as long as it is slightly larger than the maximum dimension of the sealing mechanism in the 3z direction, to avoid excessive size, which will lead to excessive size of the entire single battery, thereby affecting the energy density after it is assembled into an energy storage device.

[0082] like Fig.15 As shown, the shell component of this embodiment has the above-mentioned lower cover plate 2, including a cylinder 7 and a lower cover plate 2 fixed to any open end of the cylinder 7. In order to cooperate with the lower cover plate 2, the open end of the cylinder 7 should have a curvature.

[0083] like Fig.16 As shown, the single cell of this embodiment has the above-mentioned shell structure. When the single cell is shipped out of the factory, stored or transported, the non-recessed area 8 of the arc plate is used as the single cell support portion. Since the sealing mechanism 3 is located in the recessed portion 6 of the arc plate, the single cell can be placed stably.

[0084] It should be noted that if the sealing mechanism disclosed in Chinese patent CN220324512U or a sealing mechanism similar to it with a traction part or a traction ring is used, when using it to construct a large-capacity battery, it is necessary to stretch the traction part or the traction ring so that the traction part or the traction ring exposes the concave part or the concave part. Fig.17 As shown, the traction ring 32 is flipped up in the direction away from the weak portion 31 (in the z direction, the traction ring 32 does not expose the recessed portion and the single battery can still be placed stably) to facilitate cooperation with the packing opening device to open the packing.

Claims

1. A lower cover plate for a single cell, comprising a lower cover plate body and a sealing mechanism arranged on the lower cover plate body; characterized in that: A recessed portion recessed toward the inner cavity of the single battery is provided in a part of the main body of the lower cover plate, and a sealing mechanism is arranged in the recessed portion.

2. The lower cover plate for a single cell according to claim 1, characterized in that: The lower cover body is in the shape of a flat plate, and a protrusion is arranged on the lower cover body, the protrusion protrudes away from the inner cavity of the single battery, and the area of ​​the lower cover body without the protrusion is used as the recessed part.

3. The lower cover plate for a single cell according to claim 2, characterized in that: The protrusion is an annular boss, and the area enclosed by the annular boss is used as the recessed portion. The annular boss is arranged along the edges of the four sides of the lower cover plate body.

4. The lower cover plate for a single cell according to claim 3, characterized in that: The annular boss and the lower cover plate body are an integral part.

5. The lower cover plate for a single cell according to claim 3, characterized in that: A notch is provided on the annular boss at a position opposite to the sealing mechanism.

6. The lower cover plate for a single cell according to claim 1, characterized in that: The lower cover plate body is in the shape of a flat plate, and a blind hole recessed into the inner cavity of the single battery is provided in a partial area of ​​the lower cover plate body as the recessed portion.

7. The lower cover plate for a single cell according to claim 1, characterized in that: The main body of the lower cover plate is a curved plate, and a part of the main body of the lower cover plate is recessed toward the inner cavity of the single battery to form the recessed portion.

8. The lower cover plate for a single cell according to claim 7, characterized in that: The sealing mechanism is arranged at the center of the curved plate.

9. A housing component, characterized in that: It comprises a cylinder and a lower cover plate fixed to any open end of the cylinder, wherein the lower cover plate is the lower cover plate for a single cell according to any one of claims 1 to 8.

10. A single cell battery, characterized in that: Includes the shell component described in claim 9.

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