Battery pack lower box body, battery pack and electric equipment

Abstract

The utility model relates to a battery pack lower box body, a battery pack and electric equipment, the battery pack lower box body comprises a box body bottom plate, the upper surface of the box body bottom plate is provided with a plurality of reinforcing ribs which are arranged side by side and play a supporting role, and a smoke exhaust channel I is formed between any two adjacent reinforcing ribs. According to the utility model, the reinforcing ribs for supporting the battery cells are arranged on the box body bottom plate of the lower box body of the battery pack, and bearing structures such as a plastic base and the like which are required when the traditional cylindrical battery cells are grouped are integrated with the box body bottom plate, so that the plastic base can be cancelled when the battery pack is grouped, the types of parts are reduced, the assembly procedures are reduced, the production takt is improved, and the production efficiency is improved. The assembling efficiency in the battery pack grouping process is improved; meanwhile, the plurality of reinforcing ribs form a grid structure at the bottom of the lower box body, the impact strength of the bottom of the battery pack is improved, and the wall thickness of the box body bottom plate of the lower box body can be thinner due to the grid structure at the bottom of the lower box body, so that the light weight of the battery pack is realized.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and in particular to a battery pack lower box, a battery pack and electrical equipment. Background Art

[0002] In the existing cylindrical battery cell grouping scheme, the cylindrical battery cell and the liquid cooling plate are bonded with a thermally conductive structural adhesive, and then assembled with the bottom plastic base to form a module, and then fixed with the battery pack box to form a battery PACK. The plastic base is designed with exhaust channels and ventilation holes. When thermal runaway occurs in the battery cell, exhaust is discharged through the bottom exhaust channels and ventilation holes.

[0003] However, the existing cylindrical battery cell grouping scheme has the following problems:

[0004] (1) Structural adhesive and thermal conductive structural adhesive are required to glue the battery cell to the plastic base and the liquid cooling plate respectively. The battery cell stacking process is complicated and the production efficiency is low.

[0005] (2) High-temperature erupted materials diffuse into the battery pack through the smoke exhaust channel of the plastic base, and then are discharged out of the pack through the battery pack explosion-proof valve. During this process, the high-temperature materials may cause other insulating parts in the pack to fail, causing arcing, fire and other problems;

[0006] (3) The plastic base is not fixed to the battery case, and the module is subsequently sealed in the package by foam glue, that is, there is no connection between the plastic base and the battery case. During the dynamic driving of the vehicle, the plastic base may be worn and cause mechanical strength loss. At the same time, because the strength of the plastic base itself is poor, when the battery pack is subjected to bottom support or bottom impact conditions, the plastic base cannot absorb high-intensity impact, and the external impact energy will penetrate into the bottom of the battery cell, causing short circuits and fires.

[0007] (4) The bottom plate of the lower box needs to be thickened and strengthened to support the weight of the internal battery cells, which increases the weight of the battery pack and affects the vehicle's endurance.

[0008] (5) The plastic base can melt at high temperatures. When the battery cell erupts, the plastic base melts or deforms, blocking the smoke exhaust channel, preventing high-temperature substances from being quickly discharged, and causing thermal runaway in the pack. When the battery cell experiences thermal runaway, the plastic base becomes flammable, exacerbating the fire in the battery pack. At the same time, the plastic base will age to varying degrees due to the influence of temperature and humidity. At this time, if the bottom is supported or impacted, the plastic base cannot meet the design and requirements, resulting in external energy directly invading the battery cell, causing the battery cell to short-circuit and catch fire, and causing a safety accident. Utility Model Content

[0009] Based on this, in order to address the technical problems existing in the current cylindrical battery cell grouping solutions, the purpose of the utility model is to provide a liquid cooling assembly, a liquid cooling module, a battery pack case, a battery pack and electrical equipment.

[0010] To achieve the above purpose, the utility model adopts the following technical solutions.

[0011] The utility model provides a battery pack lower box, which comprises a box bottom plate, wherein the upper surface of the box bottom plate is provided with a plurality of reinforcing ribs arranged side by side for supporting purposes, and a smoke exhaust channel is formed between any two adjacent reinforcing ribs.

[0012] The utility model arranges reinforcing ribs for supporting the battery cells on the bottom plate of the lower box of the battery pack, and integrates supporting structures such as the plastic base required for grouping traditional cylindrical battery cells with the bottom plate of the box, so that the plastic base can be eliminated when the battery pack is grouped, the types of parts and components are reduced, the assembly process is reduced, the production cycle is improved, and the assembly efficiency of the battery pack grouping process is improved; at the same time, multiple reinforcing ribs form a grid structure at the bottom of the lower box, which improves the impact strength of the bottom of the battery pack. At the same time, due to the grid structure at the bottom of the lower box, the wall thickness of the bottom plate of the lower box can be made thinner, thereby realizing lightweight battery pack, improving the energy density of the whole pack and the endurance of electrical equipment such as electric vehicles.

[0013] As a further improvement of the above-mentioned scheme of the utility model, the lower box of the battery pack also includes a box side panel arranged around the circumference of the box bottom plate, and a plurality of longitudinal beams and two cross beams arranged at both ends of the longitudinal beams are arranged at intervals on the upper surface of the box bottom plate. A plurality of longitudinal beams, cross beams and the box side panels cooperate to form a plurality of assembly grooves, and a plurality of reinforcing ribs arranged side by side are arranged at the bottom of each assembly groove.

[0014] As a further improvement of the above-mentioned scheme of the utility model, a smoke exhaust channel 2 is arranged in one of the cross beams, and a plurality of smoke exhaust holes connected with the smoke exhaust channel 2 are spaced apart on the side of the cross beam facing the longitudinal beam, and one end of the plurality of smoke exhaust channels 1 are respectively connected with the plurality of smoke exhaust holes one by one; a closed smoke exhaust channel 3 connected with the smoke exhaust channel 2 is formed on the bottom plate of the box body, and an end of the smoke exhaust channel 3 away from the smoke exhaust channel 2 is connected with the outside.

[0015] As a further improvement of the above solution of the utility model, the reinforcing ribs are in a serpentine structure, and the reinforcing ribs are integrally formed with the bottom plate of the box body or connected by welding.

[0016] The utility model provides a battery pack, which includes the battery pack lower box as mentioned above.

[0017] As a further improvement of the above scheme of the utility model, the battery pack also includes a plurality of battery modules, each battery module includes multiple rows of cylindrical battery cells, any smoke exhaust channel one corresponds to a row of cylindrical battery cells and the two reinforcing ribs forming the smoke exhaust channel one jointly support the row of cylindrical battery cells.

[0018] As a further improvement of the above solution of the utility model, the bottom of the cylindrical battery core is bonded to the two reinforcing ribs by structural adhesive.

[0019] As a further improvement of the above-mentioned scheme of the utility model, the battery pack also includes a plurality of serpentine liquid cooling plates, the bottoms of the plurality of serpentine liquid cooling plates are respectively connected to a plurality of reinforcing ribs, and a row of cylindrical battery cells are arranged between any two adjacent serpentine liquid cooling plates, and the two side surfaces of the cylindrical battery cells are respectively bonded to the two adjacent serpentine liquid cooling plates by means of a heat-conductive structural adhesive.

[0020] As a further improvement of the above scheme of the utility model, a spacer is arranged between the tops of any two adjacent reinforcing ribs, and the spacer is fitted with the tops of the two adjacent reinforcing ribs to seal the corresponding smoke exhaust channel. The spacer includes a mica sheet fitted with the bottom of a corresponding row of cylindrical battery cells and mica paper fitted under the mica sheet. Through holes matching the size of the explosion-proof valves are opened on the mica sheet at positions corresponding to the explosion-proof valves at the bottom of each cylindrical battery cell, and annular notches arranged around the through holes are formed on the mica paper at positions corresponding to each through hole.

[0021] The utility model provides an electric device, which comprises the battery pack as mentioned above.

[0022] Compared with the prior art, the utility model has the following beneficial effects:

[0023] 1. The utility model arranges reinforcing ribs for supporting the battery cells on the bottom plate of the lower box of the battery pack, and integrates supporting structures such as the plastic base required for grouping traditional cylindrical battery cells with the bottom plate of the box, so that the plastic base can be eliminated when the battery pack is grouped, which can effectively avoid a series of problems caused by the use of the plastic base, and at the same time reduce the types of parts and components, reduce the assembly process, improve the production cycle, and improve the assembly efficiency of the battery pack grouping process; at the same time, multiple reinforcing ribs form a grid structure at the bottom of the lower box, which improves the impact resistance of the bottom of the battery pack, can absorb high-intensity impact and avoid external energy intrusion, and at the same time, due to the grid structure at the bottom of the lower box, the wall thickness of the bottom plate of the lower box can be made thinner, thereby realizing lightweight battery pack, improving the energy density of the whole pack and the endurance of electrical equipment such as electric vehicles.

[0024] 2. In the utility model, a smoke exhaust channel 1 is formed between any two adjacent reinforcing ribs for discharging high-temperature substances when the battery cell erupts. The reinforcing ribs are made of metal material, which is resistant to high temperatures and non-flammable, so they are not affected by the environment, avoiding aggravated combustion when thermal runaway occurs in the battery cell.

[0025] 3. In the lower box of the battery pack of the utility model, the smoke exhaust channel 1, the smoke exhaust channel 2, the smoke exhaust channel 3 and the structure of the partition are arranged. When the battery cell has thermal runaway, the high-temperature material is directly discharged to the outside of the package through the smoke exhaust channel 1, the smoke exhaust channel 2, and the smoke exhaust channel 3. During the whole process, the high-temperature material will not affect other components in the package, which greatly reduces the risk of thermal runaway. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of the structure of a lower box of a battery pack proposed in an embodiment of the utility model;

[0027] Figure 2 for Figure 1 Another perspective of the picture;

[0028] Figure 3 for Figure 1 A top view of

[0029] Figure 4 A schematic diagram of the structure of a battery pack proposed in an embodiment of the utility model;

[0030] Figure 5 A cross-sectional view of a battery pack proposed in an embodiment of the utility model;

[0031] Figure 6 A top view of a separator in a battery pack proposed in an embodiment of the utility model;

[0032] Figure 7 A bottom view of a separator in a battery pack according to an embodiment of the present utility model.

[0033] Figure numerals: 1. Box bottom plate; 11. Reinforcing ribs; 12. Smoke exhaust channel one; 13. Longitudinal beam; 14. Cross beam; 15. Smoke exhaust hole; 16. Smoke exhaust channel three; 2. Box side panel; 3. Cylindrical battery cell; 4. Serpentine liquid cooling plate; 5. Mica sheet; 51. Through hole; 6. Mica paper; 61. Annular notch. DETAILED DESCRIPTION

[0034] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively in conjunction with specific embodiments below. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly and comprehensively understood.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0036] Reference Figure 1-Figure 3 This embodiment provides a battery pack lower box for a battery pack, which includes a box bottom plate 1 and may also include a box side plate 2 arranged around the box bottom plate 1 in a circumferential direction.

[0037] Several longitudinal beams 13 and two cross beams 14 are arranged on the upper surface of the box bottom plate 1. Several longitudinal beams 13 are arranged at intervals in the width direction of the box bottom plate 1 and the longitudinal beams 13 extend along the length direction of the box bottom plate 1. In this embodiment, the longitudinal beams 13 can be connected to the box bottom plate 1 by several screws or welding. The two cross beams 14 are arranged along the width direction of the box bottom plate 1 and the two cross beams 14 are respectively arranged at the two ends of the longitudinal beams 13. The cross beams 14 are connected to the box bottom plate 1 by welding or are integrally formed with the box bottom plate 1. A smoke exhaust channel 2 extending along its length direction is formed in one of the cross beams 14, and a plurality of smoke exhaust holes 15 connected to the smoke exhaust channel 2 are opened on the side of the cross beam 14 facing the longitudinal beam 13. The box bottom plate 1 is integrally formed with two smoke exhaust channels 3 16 on the side of the cross beam 14 away from the longitudinal beam 13. One end of the smoke exhaust channel 3 16 is connected to the smoke exhaust channel 2 and the other end thereof passes through the box side plate 2 and is connected to the outside. In this embodiment, the box bottom plate 1, the longitudinal beam 13 and the cross beam 14 are all integrally stamped and formed from aluminum profiles.

[0038] In this embodiment, a plurality of longitudinal beams 13, transverse beams 14 and the side panels 2 of the box body cooperate to form a plurality of assembly grooves, and a plurality of supporting reinforcing ribs 11 arranged side by side are provided at the bottom of each assembly groove, and the reinforcing ribs 11 are arranged along the length direction of the bottom plate 1 of the box body, and a smoke exhaust channel 12 for the discharge of high-temperature substances when the battery cell erupts is formed between any two adjacent reinforcing ribs 11, and a plurality of smoke exhaust channels 12 are respectively connected to a plurality of smoke exhaust holes 15 in a one-to-one correspondence. In this embodiment, the reinforcing ribs 11 are made of aluminum profiles and are welded to the bottom plate 1 of the box body. Of course, in other embodiments, the reinforcing ribs 11 can also be integrally formed with the bottom plate 1 of the box body. In this embodiment, the reinforcing ribs 11 are in a serpentine structure.

[0039] Reference Figure 4-5 In this embodiment, a battery pack is also provided for use in electrical equipment such as electric vehicles, including the above-mentioned battery pack lower box, and may also include a plurality of battery modules, a plurality of liquid cooling modules and a battery pack upper box (not shown).

[0040] Several liquid cooling modules are respectively arranged in several assembly grooves. Each liquid cooling module includes a plurality of serpentine liquid cooling plates 4, and the plurality of serpentine liquid cooling plates 4 are arranged side by side in the assembly groove and the bottom of the plurality of serpentine liquid cooling plates 4 are respectively bonded to the bottom of the plurality of reinforcing ribs 11 at the bottom of the assembly groove by structural adhesive. In this embodiment, the number of serpentine liquid cooling plates 4 of each liquid cooling module can be the same or different, and the number of serpentine liquid cooling plates 4 of each liquid cooling module is reasonably set according to the width of the corresponding assembly groove. In this embodiment, the serpentine structure distribution of the serpentine liquid cooling plate 4 is consistent with the serpentine structure distribution of the reinforcing rib 11 connected to it, and the thickness of the reinforcing rib 11 is greater than the thickness of the serpentine liquid cooling plate 4, thereby ensuring the connection stability between the serpentine liquid cooling plate 4 and the reinforcing rib 11, and the serpentine wave crest of the serpentine liquid cooling plate 4 is arranged relative to the serpentine wave trough of the adjacent serpentine liquid cooling plate 4, so that a cylindrical battery cell 3 can be accommodated between the serpentine wave crest of the serpentine liquid cooling plate 4 and the serpentine wave trough of the adjacent serpentine liquid cooling plate 4. In this embodiment, the liquid cooling module adopts the existing technology, and other components of the liquid cooling module, such as the liquid inlet pipe and the liquid outlet pipe for supplying cooling liquid to the serpentine liquid cooling plate 4, are not described in detail.

[0041] In this embodiment, several battery modules are respectively arranged in one-to-one correspondence with several liquid cooling modules. Each battery module includes multiple rows of cylindrical battery cells 3, and a row of cylindrical battery cells 3 is arranged between any two adjacent serpentine liquid cooling plates 4. The bottom of the cylindrical battery cell 3 is supported by two adjacent reinforcing ribs 11 and the two sides of the cylindrical battery cell 3 are respectively bonded with the two adjacent serpentine liquid cooling plates 4. Any two adjacent serpentine liquid cooling plates 4 are connected to the side of the cylindrical battery cell 3 between them through a heat-conductive structural adhesive, and the tops of any two adjacent reinforcing ribs 11 are connected to the bottom of the cylindrical battery cell 3 between them through a structural adhesive. After grouping, two adjacent rows of cylindrical battery cells 3 share a serpentine liquid cooling plate 4, and each row of cylindrical battery cells 3 is bonded with two serpentine liquid cooling plates 4 to increase the heat dissipation area of ​​the cylindrical battery cells 3.

[0042] In this embodiment, the upper battery box is arranged above the lower battery box, and the edge of the upper box is connected to the edge of the lower battery box by bolts, thereby forming a closed battery box. In this embodiment, the upper battery box also adopts the existing technology, which will not be described in detail here.

[0043] In this embodiment, in order to reduce the risk of thermal runaway of the battery pack, Figure 6 , Figure 7A spacer is arranged between the tops of any two adjacent reinforcing ribs 11, and the spacer is fitted with the tops of the two adjacent reinforcing ribs 11 to seal the corresponding smoke exhaust channel 12. The spacer includes a mica sheet 5 fitted with the bottom of a corresponding row of cylindrical battery cells 3 and a mica paper 6 fitted under the mica sheet 5. The mica sheet 5 is provided with through holes 51 that are adapted to the size of the explosion-proof valve at the positions corresponding to the explosion-proof valves at the bottom of each cylindrical battery cell 3, and the mica paper 6 is provided with annular notches 61 arranged around the through holes 51 at the positions corresponding to the through holes 51. The above-mentioned structure of the present embodiment is set up, when the cylindrical battery cell 3 has thermal runaway, the high-temperature material inside the cylindrical battery cell 3 will erupt from the explosion-proof valve at the bottom thereof. Due to the setting of the annular notch 61 of the mica paper 6, the high-temperature material will enter the corresponding through hole 51 and break through the mica paper 6, thereby entering the corresponding exhaust channel 1 12, and then enter the exhaust channel 2 from the corresponding exhaust hole 15, and finally be discharged from the exhaust channel 3 16 to the outside of the battery pack. In this process, the high-temperature material erupted from the battery cell will no longer contact other components in the pack, greatly reducing the probability of failure of other components. The above-mentioned structure of the present embodiment is set up, because the annular notch 61 is set around the through hole 51, that is, the diameter of the annular notch 61 is larger than the diameter of the through hole 51. When a cylindrical battery cell 3 has thermal runaway, after the high-temperature material enters the exhaust channel 1 12, the high-temperature material cannot reversely break through other annular notches 61 and affect other cylindrical battery cells 3, thereby avoiding the risk of mutual influence of thermal runaway between battery cells.

[0044] When the battery pack of this embodiment is grouped, the cylindrical battery cells 3 and the serpentine liquid cooling plates 4 are stacked using thermally conductive structural adhesive to form an intermediate module, structural adhesive is applied to the top of the reinforcing ribs 11, and then the intermediate module is bonded and fixed to the top of the reinforcing ribs 11, and then the battery pack is assembled on the box.

[0045] Through the above structural design, this embodiment provides reinforcing ribs 11 for supporting the battery cells on the box bottom plate 1 of the lower box of the battery pack, and integrates the supporting structures such as the plastic base required for grouping the traditional cylindrical battery cells 3 with the box bottom plate 1, so that the plastic base can be eliminated when the battery pack is grouped, reducing the types of parts and components, reducing the assembly process, improving the production cycle, and improving the assembly efficiency of the battery pack grouping process; at the same time, multiple reinforcing ribs 11 form a grid structure at the bottom of the lower box to improve the impact strength of the bottom of the battery pack. At the same time, due to the grid structure at the bottom of the lower box, the wall thickness of the box bottom plate 1 of the lower box can be thinner, thereby realizing lightweight battery pack, improving the energy density of the whole pack and the endurance of electrical equipment such as electric vehicles.

[0046] In this embodiment, a smoke exhaust channel 12 for discharging high-temperature substances when the battery cell erupts is formed between any two adjacent reinforcing ribs 11. The reinforcing ribs 11 are made of metal, which is resistant to high temperatures and non-flammable, so they are not affected by the environment, avoiding aggravated combustion when thermal runaway occurs in the battery cell.

[0047] In the present embodiment, the smoke exhaust channel 1 12, the smoke exhaust channel 2, the smoke exhaust channel 3 16 and the structure of the partition are arranged so that when thermal runaway occurs in the battery cell, the high-temperature material is directly discharged to the outside of the package through the smoke exhaust channel 1 12, the smoke exhaust channel 2, the smoke exhaust channel 3 16. During the whole process, the high-temperature material will not affect other components in the package, thereby greatly reducing the risk of thermal runaway.

[0048] It should be noted that when a component is referred to as being "mounted on" another component, it may be directly on the other component or there may be a central component. When a component is considered to be "set on" another component, it may be directly set on the other component or there may be a central component at the same time. When a component is considered to be "fixed to" another component, it may be directly fixed on the other component or there may be a central component at the same time.

[0049] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the technical field of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "or / and" used herein includes any and all combinations of one or more related listed items.

[0050] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0051] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A battery pack lower box, comprising a box bottom plate (1), characterized in that: The upper surface of the box bottom plate (1) is provided with a plurality of reinforcing ribs (11) arranged side by side for supporting purposes, and a smoke exhaust channel (12) is formed between any two adjacent reinforcing ribs (11).

2. The battery pack lower box according to claim 1, characterized in that: The battery pack lower box also includes a box side plate (2) arranged around the box bottom plate (1); a plurality of longitudinal beams (13) and two cross beams (14) arranged at both ends of the longitudinal beams (13) are arranged at intervals on the upper surface of the box bottom plate (1); a plurality of assembly grooves are formed by the cooperation of the plurality of longitudinal beams (13), the cross beams (14) and the box side plates (2); and a plurality of reinforcing ribs (11) arranged side by side are arranged at the bottom of each assembly groove.

3. The battery pack lower box according to claim 2, characterized in that: A second smoke exhaust channel is arranged in one of the cross beams (14), and a plurality of smoke exhaust holes (15) connected to the second smoke exhaust channel are arranged at intervals on one side of the cross beam (14) facing the longitudinal beam (13), and one end of the plurality of smoke exhaust channels (12) are respectively connected to the plurality of smoke exhaust holes (15) in a one-to-one correspondence; a closed smoke exhaust channel (16) connected to the second smoke exhaust channel is formed on the bottom plate (1) of the box body, and one end of the smoke exhaust channel (16) away from the second smoke exhaust channel is connected to the outside.

4. The battery pack lower box according to claim 1, characterized in that: The reinforcing rib (11) is in a serpentine structure, and the reinforcing rib (11) and the box bottom plate (1) are integrally formed or welded together.

5. A battery pack, characterized in that: It includes a battery pack lower box as described in any one of claims 1-4.

6. The battery pack according to claim 5, characterized in that: The battery pack also includes a plurality of battery modules, each of which includes a plurality of rows of cylindrical battery cells (3), and any one of the smoke exhaust channels (12) corresponds to a row of cylindrical battery cells (3), and the two reinforcing ribs (11) forming the smoke exhaust channel (12) jointly support the row of cylindrical battery cells (3).

7. The battery pack according to claim 6, characterized in that: The bottom of the cylindrical battery core (3) is bonded to the two reinforcing ribs (11) by means of structural adhesive.

8. The battery pack according to claim 6, characterized in that: The battery pack further comprises a plurality of serpentine liquid cooling plates (4), the bottoms of the plurality of serpentine liquid cooling plates (4) are respectively connected to a plurality of reinforcing ribs (11), and a row of cylindrical cells (3) is arranged between any two adjacent serpentine liquid cooling plates (4), and the two side surfaces of the cylindrical cells (3) are respectively bonded to the two adjacent serpentine liquid cooling plates (4) by means of a heat-conducting structural adhesive.

9. The battery pack according to claim 6, characterized in that: A spacer is provided between the tops of any two adjacent reinforcing ribs (11), and the spacer is bonded to the tops of the two adjacent reinforcing ribs (11) to seal the corresponding smoke exhaust channel (12). The spacer comprises a mica sheet (5) bonded to the bottom of a corresponding row of cylindrical battery cells (3) and a mica paper (6) bonded below the mica sheet (5). Through holes (51) matching the size of the explosion-proof valve are provided on the mica sheet (5) at positions corresponding to the explosion-proof valves at the bottom of each cylindrical battery cell (3), and annular notches (61) arranged around the through holes (51) are formed on the mica paper (6) at positions corresponding to each through hole (51).

10. An electrical device, characterized in that: It comprises a battery pack as claimed in any one of claims 5 to 9.

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