Battery pack and electric device

Abstract

The application provides a battery pack and a power utilization equipment, and relates to the technical field of power batteries. A switching bridge structure is connected between two battery cells to make the two battery cells conductive, and one end of one battery cell away from the switching bridge structure forms a positive pole column assembly, and one end of the other battery cell away from the switching bridge structure forms a negative pole column assembly. The switching bridge structure is arranged between the two battery cells, so that the two battery cells can be made conductive, and since at least part of the structure of the switching bridge structure is exposed outside the battery cells, the two battery cells can be used as a structural member to bear load after being integrated into one whole, the structural strength is improved, and the consistency of stress is ensured when the product is subjected to force impact, so that the safety of the product is improved.

Description

Technical Field

[0001] This application relates to the field of power battery technology, and more specifically, to a battery pack and electrical equipment. Background Technology

[0002] A typical battery consists of assembling multiple cells into a battery module, and then integrating multiple battery modules into a battery pack, i.e., cell-battery module-battery pack. CTP (Cell to Pack) technology, on the other hand, refers to directly integrating cells into a battery pack, eliminating the intermediate step of assembling cells into battery modules.

[0003] For CTP battery packs, it is often necessary to add horizontal and vertical beams inside the box to strengthen the structural strength of the battery pack. However, considering the issue of space utilization, some adopt a large battery pack approach instead of the previous multiple small battery pack approach. That is, the side plates between multiple small battery packs are removed, and multiple stacked cells are tightened together by using tie rods or cable ties to form a large battery pack.

[0004] While this tightening method ensures that multiple cells remain secure, it only provides tightening in one direction and cannot buffer forces in specific areas. This leads to uneven stress on the cells during battery pack use, causing localized deformation and increasing the safety risks associated with battery use. Summary of the Invention

[0005] The purpose of this application is to provide a battery pack and electrical device that can improve the overall structural strength of the battery pack while ensuring the consistency of stress, thereby improving the safety of the product.

[0006] To achieve the above objectives, this application adopts the following technical solution: In a first aspect, this application provides a bridge structure that connects two battery cells to enable the two battery cells to conduct electricity, wherein one of the battery cells forms a positive terminal assembly at the end away from the bridge structure, and the other battery cell forms a negative terminal assembly at the end away from the bridge structure.

[0007] In the above implementation process, a transition bridge structure is set between the two battery cells, which enables the two battery cells to conduct electricity. Since at least a part of the structure of the transition bridge structure is exposed to the outside of the battery cells, the two battery cells can be integrated as a whole and can serve as a structural component to bear loads, thereby improving their structural strength. Furthermore, it ensures the consistency of force when subjected to impact, thereby improving the safety of the product.

[0008] In some embodiments, the adapter bridge structure includes a connecting bridge, a conductive block, and an insulating sheet. The connecting bridge is provided with a mounting groove. At least a portion of the conductive block is disposed in the mounting groove, and both ends of the conductive block are respectively connected to the battery cell. The insulating sheet is sleeved on the conductive block and is located on the left and right sides of the connecting bridge.

[0009] In the above process, the conductive block is placed in the mounting groove of the connecting bridge and welded to the two battery cells respectively to achieve the conduction of the two battery cells. The insulating sheet is sleeved on the conductive block and located on the left and right sides of the connecting bridge to achieve the insulation of the overall structure and ensure non-conductivity. Furthermore, by setting the transition bridge structure, the connection strength between the two battery cells can be improved to ensure the consistency of the stress.

[0010] In some embodiments, the connecting bridge is provided with an inlet hole and an outlet hole, the inlet hole and the outlet hole are connected, and the outlet hole is located on the left and right sides of the connecting bridge, so that when electrolyte is introduced through the inlet hole, the electrolyte can enter the interior of the two cells through the outlet hole respectively.

[0011] In the above process, the connecting bridge is provided with interconnected inlet and outlet ports, so that when two cells are connected through the adapter bridge structure, electrolyte can be injected into the two cells through the inlet and outlet ports, thereby realizing the normal charging and discharging of the cells.

[0012] In some embodiments, the outer edge of the connecting bridge is provided with a protrusion, such that when at least a portion of the connecting bridge is disposed inside the battery cell, the left and right sides of the protrusion respectively fit against the outer side of the battery cell. By providing a protrusion on the connecting bridge, when the adapter bridge structure is welded to the battery cell, the protrusion can fit against and be fixed to the battery cell, which can enhance the strength between the battery cells, make full use of the small-sized battery cells, and achieve high compatibility.

[0013] In some embodiments, the protrusion is provided with the electrolyte inlet hole. This facilitates the addition of electrolyte to the battery cell during the assembly process between the battery cell and the adapter bridge structure, thereby improving work efficiency.

[0014] In some embodiments, the insulating sheet is provided with clearance holes that are aligned one-to-one with the liquid outlet holes, so that when the liquid outlet holes output the electrolyte, the electrolyte can pass through the clearance holes and enter the interior of the battery cell.

[0015] In some embodiments, the adapter bridge structure further includes a snap-fit ​​element, the conductive block being provided with a snap-fit ​​groove adapted to the snap-fit ​​element, and the snap-fit ​​element being disposed on the side of the insulating sheet away from the connecting bridge.

[0016] In the above process, the snap-fit ​​component is located on the side of the insulating sheet away from the connecting bridge. After the snap-fit ​​component is adapted to the snap-fit ​​groove, the conductive block, the connector and the insulating sheet can be formed into a whole, ensuring the stability of the adapter bridge structure and thus improving the safety of the product.

[0017] In some embodiments, the snap-fit ​​member is configured as an opening, and an extension is provided at the opening of the snap-fit ​​member, with at least a portion of the extension disposed within the snap-fit ​​groove. The snap-fit ​​member snaps onto the conductive block through its opening, facilitating the connection and disassembly of the snap-fit ​​member and the conductive block, ensuring connection stability while improving its working efficiency.

[0018] Secondly, this application also provides a battery pack, comprising: a plurality of battery cells, wherein at least two of the battery cells are distributed in a left-right direction; and a bridge structure as described in any of the preceding claims, wherein the bridge structure is disposed between two of the battery cells distributed in the left-right direction, and the bridge structure is welded to the tabs of the battery cells.

[0019] In the above implementation process, a transition bridge structure is set between two cells distributed along the left and right sides. When the two cells and the transition bridge structure form a whole, and are assembled into a battery pack, the structure can form a structural component and have a certain load-bearing strength, thereby improving the safety of the product.

[0020] In some embodiments, the battery cell includes a housing, terminals, and a winding, the winding being disposed in the inner cavity of the housing, and the winding having a first tab and a second tab, one of the first tab or the second tab being configured to be welded to the adapter bridge, and the other being configured to be welded to the terminal to form a positive terminal assembly or a negative terminal assembly.

[0021] Thirdly, this application also provides an electrical device including a battery pack as described in any of the above claims.

[0022] Since the electrical equipment provided in the third aspect of this application includes the battery pack described in the second aspect of the technical solution, it has all the technical effects of the above-described embodiments, which will not be repeated here.

[0023] Other features and advantages of this application will be set forth in the following description and will be apparent in part from the description or may be learned by practicing embodiments of this application. The objectives and other advantages of this application may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For users of ordinary skills in the art, other related drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the connection between a bridge structure and a battery cell, as disclosed in an embodiment of this application.

[0026] Figure 2 yes Figure 1 A sectional view.

[0027] Figure 3 yes Figure 2 A magnified view of a portion of the image.

[0028] Figure 4 This is an exploded view of a bridge structure and a battery cell disclosed in an embodiment of this application.

[0029] Figure 5 This is an exploded schematic diagram of a transition bridge structure disclosed in an embodiment of this application.

[0030] Figure 6 This is a front view of a transition bridge structure disclosed in an embodiment of this application.

[0031] Figure 7 yes Figure 6 A sectional view.

[0032] Figure Labels 100. Adapter bridge structure; 101. Connecting bridge; 1011. Liquid inlet; 1012. Liquid outlet; 1013. Protrusion; 102. Conductive block; 1021. Snap-fit ​​groove; 103. Insulating sheet; 1031. Clearance hole; 104. Snap-fit ​​component; 1041. Extension; 200. Battery cell; 201. Housing; 202. Electrode roll; 203. Positive electrode assembly; 204. Negative electrode assembly; 205. First electrode tab; 206. Second electrode tab. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by users of ordinary skill in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0035] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0036] In the description of this application, it should be noted that the terms "upper", "lower", "left", "right", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the product of this application is usually placed in when in use. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0037] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0038] Example Currently, the battery pack system is the "heart" of electric vehicles, and the CTP module is the core electrical energy component of the battery pack system. The main function of the CTP module is to protect the battery cells and output power energy.

[0039] For CTP battery packs, existing battery packs often have crossbeams and longitudinal beams in the middle to strengthen the structural strength of the battery pack. However, with the improvement of battery pack utilization, it is now desirable to reduce the number of crossbeams and longitudinal beams in the battery pack so that more cells can be placed. If the crossbeams and longitudinal beams are eliminated, there will be a problem of insufficient strength. Therefore, it is desirable for the cells to also bear part of the structural components to increase the overall structural strength.

[0040] In view of this, such as Figures 1-4As shown, in a first aspect, this application provides a transition bridge structure 100, which is connected between two battery cells 200 to enable the two battery cells 200 to conduct electricity, wherein one of the battery cells 200 forms a positive terminal assembly 203 at the end away from the transition bridge structure 100, and the other battery cell 200 forms a negative terminal assembly 204 at the end away from the transition bridge structure 100.

[0041] For example, a portion of the adapter bridge structure 100 is disposed inside the battery cell 200. The adapter bridge structure 100 and the battery cell 200 can be fixed by welding. The outer surface of the adapter structure can be flush with the outer surface of the housing 201 of the battery cell 200. Welding is then performed along the flush position to achieve fixation and increase the connection strength between the two battery cells 200. The adapter bridge structure 100 is disposed between two adjacent battery cells 200 to form a positive terminal assembly 203 and a negative terminal assembly 204, which can be used to connect with the wire harness isolation plate assembly to realize the charging and discharging of the battery cell 200.

[0042] In the above implementation process, a transition bridge structure 100 is provided between the two battery cells 200. This enables the two battery cells 200 to conduct electricity. Since at least a part of the structure of the transition bridge structure 100 is exposed outside the battery cells 200, the two battery cells 200 can be integrated as a whole and can serve as a structural component to bear loads, thereby improving their structural strength. Furthermore, it ensures the consistency of force distribution when subjected to impact, thus improving the safety of the product.

[0043] like Figure 5 As shown, the transition bridge structure 100 includes a connecting bridge 101, a conductive block 102, and an insulating sheet 103. The connecting bridge 101 is provided with a mounting groove. At least a portion of the conductive block 102 is disposed within the mounting groove, and both ends of the conductive block 102 are respectively connected to the battery cell 200. The insulating sheet 103 is sleeved on the conductive block 102 and located on the left and right sides of the connecting bridge 101. It can be understood that in order to ensure good insulation of the transition bridge structure 100, the surface of the connecting bridge 101 can be insulated. The insulation method can be to spray an insulating layer on its surface or to cover its surface with insulating material, etc. Because the connecting bridge 101 is insulated, both the connecting bridge 101 and the insulating sheet 103 are in an insulated state when they are sleeved on the conductive block 102.

[0044] In the above implementation process, the conductive block 102 is set in the mounting groove of the connecting bridge 101 and is welded to the two battery cells 200 respectively to realize the conduction of the two battery cells 200. The insulating sheet 103 is sleeved on the conductive block 102 and is located on the left and right sides of the connecting bridge 101, which can realize the insulation of the overall structure and ensure non-conductivity. Furthermore, by setting the transition bridge structure 100, the connection strength between the two battery cells 200 can be realized, ensuring the consistency of the force.

[0045] like Figures 5-7 As shown, the connecting bridge 101 is provided with an inlet hole 1011 and an outlet hole 1012. The inlet hole 1011 and the outlet hole 1012 are connected. The outlet holes 1012 are located on the left and right sides of the connecting bridge 101, so that when electrolyte is input through the inlet hole 1011, the electrolyte can enter the interior of the two battery cells 200 through the outlet holes 1012 respectively. For example, the connecting bridge 101 is provided with a pipe, and the inlet hole 1011 is connected to the outlet hole 1012 through the pipe. There are two outlet holes 1012, so that one outlet hole 1012 is connected to the battery cell 200 on the left and the other outlet hole 1012 is connected to the battery cell 200 on the right. The position of the inlet hole 1011 and the position and size of the outlet hole 1012 are not specifically limited and can be set according to the actual situation.

[0046] In the above implementation process, the connecting bridge 101 is provided with an inlet hole 1011 and an outlet hole 1012 that are interconnected, so that when the two cells 200 are connected through the adapter bridge structure 100, electrolyte can be injected into the two cells 200 through the inlet hole 1011 and the outlet hole 1012, thereby realizing the normal charging and discharging of the cells 200.

[0047] like Figure 3 or Figure 5 As shown, the outer edge of the connecting bridge 101 is provided with a protrusion 1013, so that when at least a portion of the structure of the connecting bridge 101 is disposed inside the battery cell 200, the left and right sides of the protrusion 1013 are respectively attached to the outer side of the battery cell 200. For example, the protrusion 1013 is located in the middle of the connecting bridge 101 to form a stepped shape, so that when the transition bridge structure 100 is welded to the battery cell 200, a portion of the structure of the connecting bridge 101 is located inside the battery cell 200, and the sidewall of the protrusion 1013 is attached to the end of the battery cell 200. By providing the protrusion 1013 on the connecting bridge 101, when the transition bridge structure 100 is welded to the battery cell 200, the protrusion 1013 can be attached to and fixed to the battery cell 200, which can enhance the strength between the battery cells 200, make full use of the small-sized battery cell 200, and has high compatibility.

[0048] In some embodiments, the protrusion 1013 is provided with the liquid inlet hole 1011. This facilitates the addition of electrolyte to the battery cell 200 during the assembly process between the battery cell 200 and the adapter bridge structure 100, thereby improving work efficiency.

[0049] Please refer to again Figure 5 The insulating sheet 103 is provided with clearance holes 1031 that are aligned one-to-one with the liquid outlet holes 1012, so that when the liquid outlet holes 1012 output the electrolyte, the electrolyte can pass through the clearance holes 1031 and enter the interior of the battery cell 200.

[0050] In some embodiments, the adapter bridge structure 100 further includes a snap-fit ​​member 104, which includes, but is not limited to, a snap-fit ​​pin. The conductive block 102 is provided with a snap-fit ​​groove 1021 adapted to the snap-fit ​​member 104. The snap-fit ​​member 104 is disposed on the side of the insulating sheet 103 away from the connecting bridge 101. Through the snap-fit ​​member 104, the insulating sheet 103 and the connecting bridge 101 can be fixed at the middle position of the conductive block 102.

[0051] In the above implementation process, the snap-fit ​​component 104 is disposed on the side of the insulating sheet 103 away from the connecting bridge 101, so that after the snap-fit ​​component 104 is adapted to the snap-fit ​​groove 1021, the conductive block 102, the connector and the insulating sheet 103 can be formed into a whole, ensuring the stability of the adapter bridge structure 100 and thus improving the safety of the product.

[0052] In some embodiments, the snap-fit ​​member 104 is configured as an opening, and an extension 1041 is provided at the opening of the snap-fit ​​member 104. At least a portion of the extension 1041 is structurally disposed within the snap-fit ​​groove 1021. The snap-fit ​​member 104 snaps onto the conductive block 102 through its opening, which facilitates the connection and disassembly of the snap-fit ​​member 104 and the conductive block 102, ensuring connection stability while improving its working efficiency.

[0053] Secondly, this application also provides a battery pack, comprising: a plurality of battery cells 200, wherein at least two of the battery cells 200 are distributed in a left-right direction; and a transition bridge structure 100 as described above, wherein the transition bridge structure 100 is disposed between two of the battery cells 200 distributed in the left-right direction, and the transition bridge is welded to the tabs of the battery cells 200.

[0054] For example, a transition bridge structure 100 is provided between two battery cells 200 distributed along the left-right direction, such that one end of the battery cell 200 on the left is used to form a positive terminal assembly 203, and the other end is used to weld to the conductive block 102 of the transition bridge structure 100; one end of the battery cell 200 on the right is used to form a negative terminal assembly 204, and the other end is used to weld to the conductive block 102 of the transition bridge structure 100, thereby fixing the two battery cells 200 and improving the strength of the overall structure.

[0055] It is understood that the number of the transition bridge structure 100 can be set according to the number of the battery cells 200. For example, when there are two battery cells 200 distributed in the left and right direction, there can be one transition bridge structure 100; when there are three battery cells 200 distributed in the left and right direction, there can be two transition bridges 100, and so on. This will not be elaborated on here.

[0056] It should be noted that the processing flow of the battery cell 200 and the transition bridge structure 100 is as follows: For the battery cell 200 on the left: firstly, the electrode roll 202 of the battery cell 200 is placed inside the housing 201 of the battery cell 200; then, the negative electrode tab (first tab 205) of the battery cell 200 is welded to the conductive block 102 of the transition bridge structure 100; subsequently, the housing 201 is welded to the connecting bridge 101 of the transition bridge structure 100; and the positive electrode tab (second tab 206) of the battery cell 200 is welded to the terminal to form the positive terminal assembly 203, thus completing the assembly of the battery cell 200 on the left; wherein the battery cell 200 on the right is connected to the transition bridge structure... The assembly principle of structure 100 is the same as that of the battery cell 200 on the left. The negative electrode tab (first tab 205) of the battery cell 200 on the right is welded to the negative electrode to form a negative electrode assembly. Finally, the electrolyte is injected through the liquid inlet 1011 of the transition bridge structure 100. The electrolyte flows into the interior of the battery cells 200 on both sides from the liquid outlet 1012. After the electrolyte is injected, the liquid inlet 1011 is sealed to complete the connection between the battery cell 200 and the transition bridge structure 100. It can be understood that all processes that are welded to the shell 201 of the battery cell 200 are required to achieve a sealing effect to ensure that the electrolyte does not flow out.

[0057] In the above implementation process, a transition bridge structure 100 is provided between two cells 200 distributed along the left and right sides, so that when the two cells 200 and the transition bridge structure 100 form a whole, the structure can form a structural component and have a certain load-bearing strength when assembled into a battery pack, thus improving the safety of the product.

[0058] In some embodiments, the battery cell 200 includes a housing 201, a terminal post, and a terminal roll 202. The terminal roll 202 is disposed in the inner cavity of the housing 201, and the terminal roll 202 is provided with a first tab 205 and a second tab 206. One of the first tab 205 or the second tab 206 is configured to be welded to the adapter bridge, and the other is configured to be welded to the terminal post to form a positive terminal post assembly 203 or a negative terminal post assembly 204.

[0059] Thirdly, this application also provides an electrical device, including the battery pack described above. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Among them, electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc., and spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0060] When the electrical equipment is a vehicle, the vehicle can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery pack is installed inside the vehicle, and the battery pack can be located at the bottom, front, or rear of the vehicle. The battery pack can be used to power the vehicle; for example, it can serve as the vehicle's operating power source. The vehicle may also include a controller and a motor. The controller is used to control the battery pack to power the motor, for example, to meet the power needs of starting, navigation, and driving the vehicle.

[0061] In some embodiments of this application, the battery pack can not only serve as the operating power source for the vehicle, but also as the driving power source for the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0062] Since the electrical equipment provided in the third aspect of this application includes the battery pack described in the second aspect of the technical solution, it has all the technical effects of the above-described embodiments, which will not be repeated here.

[0063] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery pack, characterized in that, include: A plurality of battery cells, wherein at least two of the battery cells are distributed along a left-right direction; A bridge structure is provided, which is connected between two battery cells and is welded to the tabs of the battery cells to enable the two battery cells to conduct electricity. One of the battery cells forms a positive terminal assembly at the end away from the bridge structure, and the other battery cell forms a negative terminal assembly at the end away from the bridge structure. The adapter bridge structure includes a connecting bridge, a conductive block, an insulating sheet, and a snap-fit ​​component. The connecting bridge is provided with a mounting groove. At least a portion of the conductive block is disposed in the mounting groove, and both ends of the conductive block are respectively connected to the battery cell. The insulating sheet is sleeved on the conductive block and is located on the left and right sides of the connecting bridge. The conductive block is provided with a snap-fit ​​groove adapted to the snap-fit ​​component, and the snap-fit ​​component is disposed on the side of the insulating sheet away from the connecting bridge. The outer surface of the adapter bridge structure is flush with the outer surface of the battery cell's casing, and they are welded together at the same level.

2. The battery pack according to claim 1, characterized in that, The connecting bridge is provided with an inlet and an outlet, which are connected to each other. The outlet is located on the left and right sides of the connecting bridge so that when electrolyte is introduced through the inlet, the electrolyte can enter the interior of the two cells through the outlet.

3. The battery pack according to claim 2, characterized in that, The outer edge of the connecting bridge is provided with a protrusion, so that when at least a portion of the structure of the connecting bridge is disposed inside the battery cell, the left and right sides of the protrusion are respectively attached to the outer side of the battery cell.

4. The battery pack according to claim 3, characterized in that, The protrusion is provided with the liquid inlet hole.

5. The battery pack according to claim 2, characterized in that, The insulating sheet is provided with clearance holes that are aligned one-to-one with the liquid outlet holes, so that when the liquid outlet holes output the electrolyte, the electrolyte can pass through the clearance holes and enter the interior of the battery cell.

6. The battery pack according to claim 1, characterized in that, The snap-fit ​​component is configured as an opening, and an extension is provided at the opening of the snap-fit ​​component, with at least a portion of the extension being configured within the snap-fit ​​groove.

7. The battery pack according to claim 6, characterized in that, The battery cell includes a housing, terminals, and a winding. The winding is disposed in the inner cavity of the housing and has a first tab and a second tab. One of the first tab or the second tab is configured to be welded to the transition bridge structure, and the other is configured to be welded to the terminal to form a positive terminal assembly or a negative terminal assembly.

8. An electrical appliance, characterized in that, Includes the battery pack as described in any one of claims 1-7.

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