Battery pack and electric equipment

Abstract

The utility model relates to the technical field of new energy batteries, and discloses a battery pack and electric equipment, and the battery pack comprises a box body which is provided with an accommodating cavity; the rubber blocking strip is arranged in the containing cavity; the battery monomer comprises a shell, an anti-explosion valve and a first insulating film; the shell comprises a bottom plate and a side plate connected with the bottom plate, the bottom plate is provided with an anti-explosion hole, and the rubber blocking strip is arranged between the bottom plate and the box body; the explosion-proof valve cover seals the explosion-proof hole, the first insulating film is provided with a gas channel, the gas channel penetrates through the first insulating film in the first direction, the first insulating film wraps at least part of the bottom plate, the bottom plate is provided with an exposed part between the first insulating film and the side plate in the second direction, and the exposed part and the adhesive blocking strip are oppositely arranged in the first direction. The first insulating film performs insulation protection on the area around the explosion-proof valve, so that the electrolyte can be prevented from corroding the shell around the explosion-proof valve when the electrolyte leaks, and the insulating property of the battery monomer is improved.

Description

Technical Field

[0001] This utility model relates to the field of new energy battery technology, and in particular to a battery pack and electrical equipment. Background Technology

[0002] Lithium-ion batteries are typically equipped with explosion-proof valves. When the gas level reaches the critical explosion-proof point, the valve opens and connects to the outside environment, quickly releasing the internal pressure of the lithium-ion battery. For lithium-ion batteries, the main factors determining their safety performance are the battery's insulation protection and the timely pressure relief performance of the explosion-proof valve in the event of thermal runaway.

[0003] Currently, the explosion-proof valve of prismatic lithium batteries is usually located on the top cover or at the bottom of the casing. Lithium batteries with the terminal post on the top cover and the explosion-proof valve at the bottom of the casing offer better thermal separation, significantly improving the safety performance of the battery pack. The casing of prismatic lithium batteries uses an aluminum structure. To achieve insulation, an insulating film is usually wrapped around the casing, avoiding the explosion-proof valve area. During assembly, the lithium batteries are glued to the battery pack housing. To prevent the adhesive layer from entering the explosion-proof valve channel at the bottom of the lithium battery and affecting pressure relief performance, a sealant strip is installed on both sides of the explosion-proof valve to prevent adhesive layer from entering the valve channel.

[0004] After disassembling the battery pack, it was found that some electrolyte would still leak out of the lithium battery after thermal runaway. The electrolyte would corrode the adhesive layer and the sealing strip, affecting the sealing between the sealing strip, the casing and the battery shell. The electrolyte would then enter the area around the explosion-proof valve between the sealing strips, corroding the shell of the explosion-proof valve area and affecting the electrical safety of the lithium battery. Utility Model Content

[0005] The purpose of this invention is to provide a battery pack to solve the problem in the prior art where leakage of lithium battery electrolyte corrodes the shell of the explosion-proof valve area, affecting electrical safety; this invention also provides an electrical device using this battery pack.

[0006] To achieve the above objectives, this utility model provides a battery pack having intersecting first and second directions, the battery pack comprising:

[0007] The box body has a receiving cavity;

[0008] A rubber-blocking strip is provided in the receiving cavity;

[0009] A battery cell is disposed in the receiving cavity, and the battery cell includes a housing, an explosion-proof valve, and a first insulating membrane;

[0010] The housing includes a bottom plate and side plates connected to each other. The bottom plate is provided with an explosion-proof hole that penetrates the bottom plate along the first direction. The rubber baffle strip is disposed between the bottom plate and the housing.

[0011] The explosion-proof valve cover seals the explosion-proof hole. The first insulating film and the explosion-proof valve are arranged opposite to each other along the first direction. The first insulating film is provided with a gas channel that penetrates the first insulating film along the first direction. The first insulating film covers part of the bottom plate. Along the second direction, the bottom plate has an exposed portion between the first insulating film and the side plate. The exposed portion and the rubber-blocking strip are arranged opposite to each other along the first direction.

[0012] In some embodiments, the battery cell further includes a protective sheet disposed between the explosion-proof valve and the first insulating film, and a gap is formed between the first insulating film and the protective sheet along the first direction.

[0013] In some embodiments, along the first direction, the first insulating film, in its orthogonal projection onto the base plate, covers the protective sheet.

[0014] In some embodiments, the first insulating film is provided with grooves and / or pores, the grooves and / or pores penetrating the first insulating film along the first direction, and the grooves and / or pores forming the gas channel.

[0015] In some embodiments, the battery pack further has a third direction that intersects the first direction and the second direction in pairs, and along the third direction, there is a gap between the first insulating film and the side plate.

[0016] In some embodiments, the battery pack further has a third direction that intersects the first direction and the second direction in pairs. The side plate includes a first plate and a second plate. Two first plates are disposed opposite each other, and two second plates are disposed opposite each other. Along the second direction, there is a gap between the first insulating film and at least one second plate. Along the third direction, there is a gap between the first insulating film and at least one first plate.

[0017] In some embodiments, the battery cell further includes a second insulating film, the second insulating film including a main body and a first folded edge connected to the main body, the main body being attached to the first plate, the first folded edge being attached to the base plate, and a gap being formed between the first folded edge and the protective sheet along the third direction.

[0018] In some embodiments, the battery cell further includes a cover plate and an electrode post disposed on the cover plate. The cover plate is fixedly connected to the first plate and the second plate. The second insulating film further includes a second folded edge connected to the main body. The second folded edge is attached to the cover plate and has a gap with the electrode post along the third direction.

[0019] In some embodiments, the battery cell further includes a third insulating film and a fourth insulating film. The third insulating film includes a first flange and a second flange connected to the first flange. The first flange is attached to the second plate, and the second flange is attached to the cover plate.

[0020] The fourth insulating film includes a third flange and a fourth flange. The third flange is attached to the second plate, and the fourth flange is attached to the bottom plate. Along the first direction, there is a gap between the first flange and the third flange, and along the second direction, there is a gap between the fourth flange and the first insulating film.

[0021] The second insulating film also includes a third folded edge connected to the main body portion, the third folded edge being attached to the second plate.

[0022] This utility model also provides an electrical device, including the battery pack described in any of the above technical solutions.

[0023] Compared with the prior art, the battery pack and electrical equipment of this utility model embodiment have the following advantages: a first insulating film is covered on the bottom plate of the shell, and a baffle strip corresponds to the exposed part of the bottom plate along a first direction, so that the first insulating film is located on the side of the baffle strip closer to the explosion-proof valve. The first insulating film can provide insulation protection for the area around the explosion-proof valve, and can prevent the electrolyte from corroding the shell around the explosion-proof valve when the electrolyte leaks, thereby improving the insulation performance of the battery cell; at the same time, a gas channel is provided on the first insulating film, which also effectively connects the explosion-proof valve with the external space, ensuring that the explosion-proof valve can be opened normally when the battery cell thermally runs away. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of a single battery cell in the battery pack of this utility model;

[0025] Figure 2 yes Figure 1 A schematic diagram of the top structure of a single battery cell;

[0026] Figure 3 yes Figure 1 A schematic diagram of the structure of a single battery cell after omitting the second, third, and fourth insulating films;

[0027] Figure 4 yes Figure 1A cross-sectional view of a single battery cell;

[0028] Figure 5 yes Figure 4 An enlarged schematic diagram of cell A;

[0029] Figure 6 This is a schematic diagram of one embodiment of a battery cell of a utility model;

[0030] Figure 7 This is a schematic diagram of another embodiment of the battery cell of the utility model;

[0031] Figure 8 This is a schematic diagram of the battery pack structure of this utility model;

[0032] Figure 9 This is a schematic diagram of the assembly structure of the battery cell and the rubber strip of the battery pack of this utility model.

[0033] In the diagram, 1 is the casing, 11 is the bottom plate, 111 is the explosion-proof hole, 112 is the exposed part, 12 is the side plate, 121 is the first plate, 122 is the second plate, 2 is the explosion-proof valve, 3 is the first insulating film, 31 is the gas channel, 311 is the notch, 312 is the vent, 4 is the protective sheet, 6 is the second insulating film, 61 is the main body, 62 is the first folded edge, 63 is the second folded edge, 64 is the third folded edge, 7 is the cover plate, 8 is the terminal post, 9 is the third insulating film, 91 is the first flange, 92 is the second flange, 10 is the fourth insulating film, 101 is the third flange, 102 is the fourth flange, 20 is the sealing strip, 30 is the housing, 301 is the receiving cavity, 40 is the battery cell, Z is the first direction, Y is the second direction, and X is the third direction. Detailed Implementation

[0034] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit the scope of this utility model.

[0035] A preferred embodiment of the battery pack of this utility model is as follows: Figures 1 to 9 As shown, the battery pack includes a housing 30, a retaining strip 20, and individual battery cells 40.

[0036] The housing 30 has a receiving cavity 301, and both the sealing strip 20 and the battery cell 40 are disposed within the receiving cavity 301. The sealing strip 20 is located between the bottom of the battery cell 40 and the housing 30. At least two battery cells 40 are arranged side by side along the third direction X, and the sealing strip 20 covers a portion of the battery cell 40 along the third direction X.

[0037] The battery pack has a first direction Z, a second direction Y, and a third direction X that intersect each other. In this embodiment, the first direction Z, the second direction Y, and the third direction X are perpendicular to each other. The battery pack is square, wherein the first direction Z is the height direction of the battery pack, the second direction Y is the width direction of the battery pack, and the third direction X is the thickness direction of the battery pack.

[0038] The battery cell 40 includes a housing 1, an explosion-proof valve 2, and a first insulating membrane 3. The housing 1 includes a base plate 11 and a side plate 12 connected to the base plate 11. The side plate 12 and the base plate 11 form a battery cavity for accommodating electrode assemblies. The base plate 11 is provided with an explosion-proof hole 111, which penetrates the base plate 11 along a first direction Z and communicates with the battery cavity. The explosion-proof valve 2 is installed inside the explosion-proof hole 111 and seals the explosion-proof hole 111. In the event of thermal runaway of the battery cell 40, the explosion-proof valve 2 can promptly release pressure.

[0039] The first insulating film 3 covers at least part of the base plate 11 and is located on the side of the base plate 11 away from the receiving cavity. The first insulating film 3 is provided with a gas channel 31, which penetrates the first insulating film 3 along the first direction Z. The gas channel 31 forms a weak part of the first insulating film 3. When the battery cell 40 thermally runs away and causes the explosion-proof valve 2 to open, the first insulating film 3 can be destroyed through the gas channel 31, and the high-temperature and high-pressure substances can be released quickly to ensure the normal operation of the explosion-proof valve 2.

[0040] When the battery cell 40 is bonded and fixed to the battery pack housing 30, a retaining strip 20 is provided between the housing 30 and the battery cell 40. The retaining strip 20 is located between the bottom plate 11 of the battery cell 40 and the housing 30. The retaining strip 20 extends along the third direction X and covers the bottom plate 11 of each battery cell 40. There are two retaining strips 20, which are spaced apart along the second direction Y. In this embodiment, the first insulating film 3 is positioned on the bottom plate 11 between the two retaining strips 20 along the second direction Y. The first insulating film 3 and the retaining strips 20 can abut against each other, overlap, or have a micro-gap, which is less than or equal to 0.1 mm.

[0041] Along the second direction Y, the base plate 11 has an exposed portion 112 between the first insulating film 3 and the side plate 12, which is not covered by the first insulating film 3. The exposed portion 112 and the adhesive strip 20 are arranged opposite to each other along the first direction Z. When the battery cell 40 is glued to the battery pack housing 30, the exposed portion 112 of the base plate 11 is the area directly bonded to the adhesive layer. The aluminum shell is used to improve the bonding strength between the base plate 11 and the housing 30 without affecting the stability of the adhesive bonding between the battery cell 40 and the housing 30.

[0042] Since the exposed part 112 and the rubber strip 20 are arranged opposite each other along the first direction Z, the part of the base plate 11 near the explosion-proof valve 2 is covered by the first insulating film 3, thereby providing insulation protection for the area around the explosion-proof valve 2, preventing the electrolyte from corroding the shell 1 around the explosion-proof valve 2 due to the lack of an insulating film attached to the base plate 11, and improving the insulation performance of the battery cell 40.

[0043] The battery cell 40 of the battery pack is covered with a first insulating film 3 on the bottom plate 11 of the housing 1. The rubber strip 20 is aligned with the exposed part 112 of the bottom plate 11 along the first direction Z, so that the first insulating film 3 is located on the side of the rubber strip 20 closer to the explosion-proof valve 2. The first insulating film 3 can provide insulation protection for the area around the explosion-proof valve 2. In the event of electrolyte leakage, it can prevent the electrolyte from corroding the housing 1 around the explosion-proof valve 2 and improve the insulation performance of the battery cell 40. At the same time, a gas channel 31 is provided on the first insulating film 3. The gas channel 31 also effectively connects the explosion-proof valve 2 with the external space, ensuring that the explosion-proof valve 2 can be opened normally in the event of thermal runaway of the battery cell 40.

[0044] In some embodiments, the battery cell 40 further includes a protective sheet 4, which is disposed between the explosion-proof valve 2 and the first insulating film 3, and there is a gap between the first insulating film 3 and the protective sheet 4 along the first direction Z.

[0045] The protective plate 4 and the first insulating film 3 are both disposed on the side of the explosion-proof valve 2 closest to the housing 30, that is, the protective plate 4 and the first insulating film 3 are located outside the explosion-proof valve 2. The protective plate 4 and the first insulating film 3 are used to protect the explosion-proof valve 2 and prevent damage to it. The protective plate 4 covers the explosion-proof valve 2 and has micropores to connect the explosion-proof valve 2 with the external space. The specific structure of the protective plate 4 is prior art and will not be described again here.

[0046] The gap between the first insulating film 3 and the protective sheet 4 allows gas to flow, preventing the first insulating film 3 from clogging the small holes on the protective sheet 4. In this embodiment, the gap between the first insulating film 3 and the protective sheet 4 is greater than or equal to 0.1 mm.

[0047] In some embodiments, such as Figure 1 As shown, the battery cell 40 covers the explosion-proof valve 2 with a protective sheet 4. At this time, the first insulating film 3 is hollowed out to avoid the protective sheet 4, ensuring that the explosion-proof valve 2 can release pressure smoothly after it is opened.

[0048] In some embodiments, such as Figure 5 As shown, the battery cell 40 includes both a protective sheet 4 and a first insulating film 3, with a gap between the first insulating film 3 and the protective sheet 4 along the first direction Z.

[0049] In some embodiments, the protective sheet 4 is omitted on the battery cell 40, and the first insulating film 3 with gas passage 31 can replace the protective sheet 4 to protect the explosion-proof valve 2.

[0050] In some embodiments, along the first direction Z, the first insulating film 3 covers the protective sheet 4 in the orthogonal projection of the base plate 11.

[0051] The first insulating film 3 covers the protective sheet 4 on the base plate 11 along the first direction Z by its orthogonal projection. The area of ​​the first insulating film 3 is greater than or equal to the area of ​​the protective sheet 4. At this time, there is a gap between the edge of the first insulating film 3 and the protective sheet 4, so that the protective sheet 4 can be opened smoothly when the explosion-proof valve 2 is opened.

[0052] In some embodiments, the first insulating film 3 is provided with grooves 311 and / or pores 312, the grooves 311 and / or pores 312 penetrate the first insulating film 3 along the first direction Z, and the grooves 311 and / or pores 312 form a gas channel 31.

[0053] like Figure 6 and Figure 7 As shown, a gas channel 31 is formed on the first insulating film 3 by a through-score 311 and / or a vent 312 extending along the first direction Z. Both the through-score 311 and the vent 312 can form weak points on the first insulating film 3. While connecting the explosion-proof valve 2 to the outside world, the first insulating film 3 can be opened smoothly for pressure relief after the explosion-proof valve 2 is opened. In this embodiment, the through-score 311 is I-shaped. In other embodiments, the through-score 311 can also be radial or curved.

[0054] In some embodiments, a gap exists between the first insulating film 3 and the side plate 12 along the third direction X.

[0055] In the third direction X, there is a gap between the first insulating film 3 and the side plate 12, so that the first insulating film 3 will not adhere to the side plate 12 of the battery cell 40, and will not increase the number of insulating film layers covering the side plate 12 of the battery cell 40. This avoids increasing the size of the battery cell 40 in the third direction X due to excessive insulating film layers, which would reduce the energy density of the battery pack. At the same time, if the first insulating film 3 were to adhere to the side plate 12, it would cause uneven thickness of the battery cell 40 along the third direction X. When the battery cell 40 is squeezed, uneven force will lead to lithium plating and damage to the battery cell 40.

[0056] In some embodiments, the side plate 12 includes a first plate 121 and a second plate 122. Two first plates 121 are disposed opposite each other, and two second plates 122 are disposed opposite each other. Along the second direction Y, there is a gap between the first insulating film 3 and at least one second plate 122, and along the third direction X, there is a gap between the first insulating film 3 and at least one first plate 121.

[0057] The side plate 12 is formed by two first plates 121 and two second plates 122, making the casing 1 of the battery body 40 square, and the entire battery body 40 a square battery. The first plate 121 is the large surface of the battery cell 40. There is a gap between the first insulating film 3 and the second plate 122 along the second direction Y, and a gap between the first insulating film 3 and the first plate 121 along the third direction X, ensuring that the first insulating film 3 does not cover the first plate 121 and the second plate 122 of the battery cell 40, thus avoiding increasing the size of the battery cell 40 in the thickness and width directions.

[0058] In some embodiments, the battery cell 40 further includes a second insulating film 6, which includes a main body 61 and a first folded edge 62 connected to the main body 61. The main body 61 is attached to a first plate 121, and the first folded edge 62 is attached to a base plate 11. Along the third direction X, there is a gap between the first folded edge 62 and the protective sheet 4.

[0059] The main body 61 of the second insulating film 6 is attached to the first plate 121, and the first folded edge 62 is attached to the base plate 11, so that the second insulating film 6 covers the entire first plate 121, increasing the insulation of the shell 1. There is a gap between the first folded edge 62 and the protective sheet 4 in the third direction X, ensuring that the first folded edge 62 will not interfere with the protective sheet 4 and that the protective sheet 4 can be opened smoothly. In this embodiment, there may be a gap between the first folded edge 62 and the first insulating film 3, or they may be stacked and bonded together.

[0060] In some embodiments, the battery cell 40 further includes a cover plate 7 and an electrode post 8 disposed on the cover plate 7. The cover plate 7 is fixedly connected to the first plate 121 and the second plate 122. The second insulating film 6 further includes a second folded edge 63 connected to the main body 61. The second folded edge 63 is attached to the cover plate and has a gap with the electrode post 8 along the third direction X.

[0061] There is a gap between the second fold 63 of the second insulating film 6 and the pole post 8, which can prevent the second insulating film 6 from interfering with the pole post 8 and ensure that the equipment can be set up normally when the second insulating film 6 is attached.

[0062] In some embodiments, the battery cell 40 further includes a third insulating film 9 and a fourth insulating film 10. The third insulating film 9 includes a first flange 91 and a second flange 92 connected to the first flange 91. The first flange 91 is attached to the second plate 122, and the second flange 92 is attached to the cover plate 7. The fourth insulating film 10 includes a third flange 101 and a fourth flange 102. The third flange 101 is attached to the second plate 122, and the fourth flange 102 is attached to the bottom plate 11. Along the first direction Z, there is a gap between the first flange 91 and the third flange 101. Along the second direction Y, there is a gap between the fourth flange 102 and the first insulating film 3. The second insulating film 6 further includes a third folded edge 64 connected to the main body 61. The third folded edge 64 is attached to the second plate 122.

[0063] A third insulating film 9 and a fourth insulating film 10 are also covered on the battery cell 40. The third insulating film 9 can increase the insulation of the second plate 122 of the casing 1. There is a gap between the first flange 91 and the third flange 101 along the third direction X. The second plate 122 is exposed at this gap. The side of the battery pack can directly contact the second plate 122 when applying adhesive, which improves the bonding strength. The third folded edge 64 of the second insulating film 6 is attached to the second plate 122. There can be a gap between the third folded edge 64 and the third insulating film 9 and the fourth insulating film 10, or they can be laminated together.

[0064] A preferred embodiment of the electrical equipment of this utility model includes a battery pack. The specific structure of the battery pack is the same as that of the battery pack described in any of the above embodiments, and will not be repeated here.

[0065] In summary, this utility model embodiment provides a battery pack and electrical equipment, which has a first insulating film covering the bottom plate of the housing. The first insulating film has perforations that are opposite to the explosion-proof valve along a first direction. The first insulating film can provide insulation protection for the area around the explosion-proof valve, and can prevent the electrolyte from corroding the housing around the explosion-proof valve when the electrolyte leaks, thereby improving the insulation performance of the battery pack. At the same time, a gas channel is provided on the first insulating film, which also effectively connects the explosion-proof valve to the external space, ensuring that the explosion-proof valve can be opened normally in the event of thermal runaway of a single battery cell.

[0066] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present utility model, and these improvements and substitutions should also be considered within the protection scope of the present utility model.

Claims

1. A battery pack, characterized by, The battery pack has a first direction and a second direction intersecting each other, and comprises: a box body provided with a receiving cavity; a glue blocking strip provided in the receiving cavity; a battery monomer provided in the receiving cavity, the battery monomer comprising a shell, an explosion-proof valve and a first insulation film; the shell comprises a bottom plate and a side plate connected to each other, the bottom plate is provided with an explosion-proof hole penetrating through the bottom plate along the first direction, and the glue blocking strip is arranged between the bottom plate and the box body; the explosion-proof valve covers the explosion-proof hole, the first insulation film is arranged opposite to the explosion-proof valve along the first direction, the first insulation film is provided with a gas passage penetrating through the first insulation film along the first direction, the first insulation film covers part of the bottom plate, and along the second direction, the bottom plate has an exposed part between the first insulation film and the side plate, and the exposed part is arranged opposite to the glue blocking strip along the first direction.

2. The battery pack of claim 1, wherein, The battery monomer further comprises a protective sheet arranged between the explosion-proof valve and the first insulation film, and along the first direction, a gap is formed between the first insulation film and the protective sheet.

3. The battery pack of claim 2, wherein, Along the first direction, the first insulation film covers the protective sheet in the orthographic projection of the bottom plate.

4. The battery pack of any one of claims 1-3, wherein, The first insulation film is provided with an incision and / or a gas hole penetrating through the first insulation film along the first direction, and the incision and / or the gas hole form the gas passage.

5. The battery pack of any one of claims 1-3, wherein, The battery pack further has a third direction intersecting with the first direction and the second direction, and along the third direction, a gap is formed between the first insulation film and the side plate.

6. The battery pack of any one of claims 1-3, wherein, The battery pack further has a third direction intersecting with the first direction and the second direction, and the side plate comprises a first plate and a second plate, two first plates are arranged opposite to each other, and two second plates are arranged opposite to each other, along the second direction, a gap is formed between the first insulation film and at least one second plate, and along the third direction, a gap is formed between the first insulation film and at least one first plate.

7. The battery pack of claim 6, wherein, The battery monomer further comprises a second insulation film, the second insulation film comprises a main body part and a first folding edge connected to the main body part, the main body part is attached to the first plate, and the first folding edge is attached to the bottom plate, along the third direction, a gap is formed between the first folding edge and the protective sheet.

8. The battery pack of claim 7, wherein, The battery monomer further comprises a cover plate and a pole provided on the cover plate, the cover plate is fixedly connected with the first plate and the second plate, the second insulation film further comprises a second folding edge connected to the main body part, the second folding edge is attached to the cover plate, and along the third direction, a gap is formed between the second folding edge and the pole.

9. The battery pack of claim 8, wherein, The battery monomer further comprises a third insulation film and a fourth insulation film, the third insulation film comprises a first folding edge and a second folding edge connected to the first folding edge, the first folding edge is attached to the second plate, and the second folding edge is attached to the cover plate. The fourth insulating film includes a third flange attached to the second plate and a fourth flange attached to the bottom plate, and has a gap between the first flange and the third flange in the first direction and a gap between the fourth flange and the first insulating film in the second direction. The second insulating film further includes a third folded edge connected to the main body portion, the third folded edge being attached to the second plate.

10. An electric device, characterized by A battery pack comprising the battery pack of any one of claims 1-9.

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