CN113036276B

CN113036276B - Battery pack and electric vehicle

Info

Publication number: CN113036276B
Application number: CN201911235443.8A
Authority: CN
Inventors: 张越; 周燕飞; 张中林
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2019-12-05
Filing date: 2019-12-05
Publication date: 2023-07-11
Anticipated expiration: 2039-12-05
Also published as: CN113036276A

Abstract

The application provides a battery pack and an electric vehicle. The battery pack comprises a first chamber and a second chamber, wherein the first chamber is a sealed chamber; the battery comprises a plurality of single batteries, a plurality of battery modules and a plurality of battery modules, wherein each single battery comprises a battery body and an electrode terminal which is arranged on the battery body and used for leading out current; the battery comprises a battery body and a first cavity, wherein a through hole is formed in the cavity wall of the first cavity, at least part of the electrode terminal penetrates through the through hole and is sealed in the first cavity, and the battery body is located in the second cavity. When the electrode terminal is independently sealed in the cavity, the influence of external environment on the electrode terminal can be reduced, the insulation failure of the high-voltage connecting piece caused by the entry of water vapor or dust or the leakage of the inside of the battery pack is avoided, and the electrical reliability of the battery pack is improved.

Description

Battery pack and electric vehicle

Technical Field

The application belongs to the technical field of batteries, and particularly relates to a battery pack and an electric vehicle.

Background

In the related art, in order to avoid water or dust in the air from entering the battery pack to cause internal short circuit, for the traditional battery pack design, the sealing space defined by the battery tray and the sealing cover needs to meet the sealing requirement of IP67, the battery tray also needs to meet the requirement independently, whether an aluminum profile flat welding tray, an aluminum die casting tray, a steel tray or a composite material tray, and a large-size tray needs to meet the sealing requirement, so that the manufacturing process has relatively high difficulty and high cost, and the lightweight design of the tray is limited to a certain extent.

In addition, in order to solve the heat dissipation problem of the battery pack, in the related art, an air cooling method is adopted, an exhaust fan is arranged on one side of a case, and when the temperature in the case is too high, cold air is exhausted outwards and supplemented through negative pressure, but dust and impurities are brought into the battery case when the air is taken in, so that a new pollution problem is generated. The other method can also adopt a battery box liquid cooling method, various pipelines are arranged between the battery packs or inside the battery box, cooling liquid is filled in the pipelines and is connected with a cooling system outside the battery box, and heat generated by the battery packs is taken away through circulation of the cooling liquid. But this method has a risk that the cooling liquid may leak to create safety.

No matter the battery pack is not sealed well, external water vapor automatically enters the battery pack or is cooled by air, dust and impurities are brought into the battery box while air is taken in, or cooling liquid is leaked, and in the battery pack, the electrode terminals of the single batteries are most easily affected to cause potential safety hazards.

Disclosure of Invention

In order to solve at least one problem in the prior art, the application provides a battery pack, a first chamber and a second chamber, wherein the first chamber is a sealed chamber; the battery comprises a plurality of single batteries, a plurality of battery modules and a plurality of battery modules, wherein each single battery comprises a battery body and an electrode terminal which is arranged on the battery body and used for leading out current; the battery comprises a battery body and a first cavity, wherein a through hole is formed in the cavity wall of the first cavity, at least part of the electrode terminal penetrates through the through hole and is sealed in the first cavity, and the battery body is located in the second cavity.

In some embodiments, a seal is provided between the wall of the through hole and the electrode terminal.

In some embodiments, a connector is disposed within the first chamber, the connector electrically connecting the electrode terminals.

In some embodiments, the connector is provided on a wall of the first chamber.

In some embodiments, an insulating support is further provided in the first chamber, and the connector is provided on the insulating support.

In some embodiments, the battery pack further comprises a sampling structure for monitoring a cell voltage or current signal, the sampling structure disposed in the first chamber.

In some embodiments, the battery pack includes an upper cover and a lower case connected to define a receiving space, and the second chamber is located in the receiving space.

In some embodiments, the first chamber is located in the receiving space.

In some embodiments, the accommodating space is provided with a box body with an opening and a protective cover arranged on the opening of the box body, and the box body is in sealing connection with the protective cover to define the first chamber.

In some embodiments, the through hole is provided on the cartridge.

In some embodiments, the battery pack further includes a partition dividing the receiving space into at least one second chamber.

In some embodiments, the partition divides the receiving space into a first chamber and a second chamber.

In some embodiments, the partition is internally formed with the first chamber.

In some embodiments, the partition includes first and second partitions disposed in spaced apart relation, the first chamber being located between the first and second partitions.

In some embodiments, the through hole is provided on at least one of the first baffle and the second baffle.

In some embodiments, the upper cover is at least partially hollow to form the first chamber.

In some embodiments, the lower housing is at least partially hollow to form the first chamber.

In some embodiments, the lower housing includes a bottom plate and a rim disposed about a periphery of the bottom plate, the rim being at least partially hollow to form the first chamber.

In some embodiments, the rim includes an inner rim and an outer rim that together define the first chamber.

In some embodiments, the through hole is provided on the inner rim.

In some embodiments, the single battery further comprises an explosion-proof valve located on the battery body, a plurality of first through holes are formed in the inner frame, a plurality of second through holes are formed in the outer frame, the explosion-proof valve and the first through holes are oppositely arranged and correspond to each other one by one, and plugging pieces are arranged at the second through holes.

In some embodiments, the battery pack further includes a guide cylinder for communicating the explosion-proof valve and the first via.

In some embodiments, an end of the guide cylinder extends to the second via.

In some embodiments, the battery body includes a length L, a thickness D, and a width H, and L > H > D; the electrode terminals include a first electrode terminal and a second electrode terminal, the battery body includes a first end and a second end along a length direction, the first electrode terminal is located at the first end, and the second electrode terminal is located at the second end.

In some embodiments, the bottom plate is provided with two frames opposite to each other in the length direction of the bottom plate, the first electrode terminal is sealed in the first cavity of one frame, and the second electrode terminal is sealed in the first cavity of the other frame; the length direction of the bottom plate is consistent with the length direction of the battery body.

In some embodiments, the upper cover and the lower case abut against an outer surface of the battery body to restrain expansion of the battery body.

In some embodiments, at least one of the upper cover and the lower housing is provided with a reinforcement.

In some embodiments, the battery body includes a length L, a thickness D, and a width H, and L > H > D; the plurality of unit cells are arranged along the width direction of the cell body to form a cell array; the upper cover and the lower case are disposed opposite to each other in the thickness direction of the battery body.

In some embodiments, at least one of the upper cover and the lower case is provided with a plurality of protrusions protruding to the outside of the battery pack at intervals, and an air channel is formed between the protrusions and the battery body; and at least one of the upper cover and the lower shell is also provided with an air inlet and an air outlet which are communicated with the air duct.

In some embodiments, the recess between two adjacent protrusions abuts against the outer surface of the battery body.

In some embodiments, the battery body includes a length L, a thickness D, and a width H, and L > H > D; the plurality of unit cells are arranged along the width direction of the cell body to form a cell array; the upper cover and the lower shell are oppositely arranged in the thickness direction of the battery body; the protruding parts extend along the width direction of the battery body, and the plurality of protruding parts are arranged along the length direction of the battery body.

In some embodiments, a plurality of layers of battery arrays are arranged along the thickness direction of the battery body, and two adjacent layers of battery arrays are bonded through a structural bonding piece.

In some embodiments, the length and thickness of the battery body satisfy: l is more than or equal to 400mm and less than or equal to 2500mm, and L/D is more than or equal to 10 and less than or equal to 208.

In a second aspect of the present application, there is provided an electric vehicle comprising the battery pack described above.

Compared with the prior art, the beneficial effect that this application had is: according to the battery pack, the electrode terminals of the single batteries are sealed in a single cavity, the cavity is isolated from the outside of the battery pack and other places of the battery pack, so that water vapor or dust is prevented from entering the inside of the battery pack or the internal short circuit or insulation failure of the electrode terminals caused by leakage in the battery pack is avoided, and the electrical reliability of the battery pack is improved; on the other hand, the method is equivalent to sealing in a local area of the battery pack, and the whole battery pack is not required to be sealed, so that the sealing requirement of the battery pack can be reduced, the manufacturing process of the battery pack is simplified, and the manufacturing cost of the battery pack is reduced.

Additional advantages and effects of the present application will be set forth in detail below.

Drawings

Fig. 1 is a schematic overall structure of a battery pack according to one embodiment of the present application;

fig. 2 is an exploded view of a battery pack provided in one embodiment of the present application;

FIG. 3 is a cross-sectional view of a battery pack provided in one embodiment of the present application;

FIG. 4 is an enlarged view of portion A of FIG. 3;

FIG. 5 is a top view of a battery pack provided in one embodiment of the present application;

fig. 6 is a schematic structural view of a battery pack according to another embodiment of the present application;

FIG. 7 is a top view of a battery pack provided in accordance with another embodiment of the present application;

FIG. 8 is a cell provided in one embodiment of the present application;

fig. 9 is a schematic structural view of another battery pack provided herein.

Reference numerals

100. A battery pack;

101. an upper cover; 1011. a protruding portion; 1012. a recessed portion;

102. a lower housing; 1021. an inner frame; 1022. an outer frame; 1023. a frame; 1024. a first via; 1025. a second via; 1026. a mounting groove; 1027. a guide cylinder;

103. an air duct; 1031. an air inlet; 1032. an air outlet;

104. a single battery; 1041. a battery body; 1042. an electrode terminal; 1043. an explosion-proof valve;

105. a reinforcing member;

106. a first chamber;

107. a second chamber;

108. a seal;

109. a through hole;

110. a connecting piece;

111. a structural adhesive;

112. a partition plate; 1121. a first separator; 1122. and a second separator.

Detailed Description

As shown in fig. 1-7, the present application provides a battery pack 100, including a first chamber 106 and a second chamber 107, wherein the first chamber 106 is a sealed chamber; a plurality of unit cells 104, the unit cells 104 including a cell body 1041 and an electrode terminal 1042 provided on the cell body 1041 for drawing current; the first chamber 106 has a through hole 109 formed in a wall thereof, and the electrode terminal 1042 is at least partially inserted through the through hole 109 and sealed in the first chamber 106, and the battery body 1041 is disposed in the second chamber 107.

In this application, the first chamber 106 may be plural, and when the first chamber 106 is plural, the positions of the first chambers 106 may be different, and the first chambers 106 are sealed chambers, it may be understood that the first chambers 106 are isolated from other places in the battery pack 100, and isolated from air and dust outside the battery pack 100.

The number of the second chambers 107 may be plural, and the positions of the second chambers 107 may be different, and the second chambers 107 may be sealed chambers or unsealed, which is not particularly limited in this application.

In order to facilitate that the electrode terminals 1042 can be located in the first chamber 106 entirely, the battery bodies 1041 of the plurality of unit batteries 104 may also be located in the first chamber 106 in a partial region, and when the partial region of the battery body 1041 is located in the first chamber 106, the battery bodies 1041 located in the first chamber 106 need to be sealed to ensure the sealing performance of the first chamber 106.

It should be noted that the first chamber 106 and the second chamber 107 are two completely different chambers, that is, at least a portion of the battery body 1041 and at least a portion of the electrode terminal 1042 are located in different chambers for the same single battery 104.

The sealing performance of the battery pack 100 is always an important performance, the sealing performance is poor, moisture or dust at the battery pack 100 enters the inside of the battery pack 100, which easily causes internal short circuit of the battery pack 100, and causes a safety problem, while in the inside of the battery pack 100, the electrode terminal 1042 is the place of the battery pack 100 with the highest requirement for electrical performance, and once moisture enters the inside of the battery pack 100 or leakage occurs, the electrical connection parts such as the electrode terminal 1042 are most easily affected.

The present application is based on the above technical problem, and seals the electronic terminals of the unit cells 104 in separate chambers, so as to reduce the influence of water vapor or dust outside the battery pack 100 entering the inside of the battery pack 100 or the leakage occurring inside the battery pack 100 on the electrode terminals 1042. In an extreme case, even if the second chamber 107 is waded, the electrode terminal 1042 in the first chamber 106 is not affected.

On the other hand, the present application corresponds to sealing in a partial region of the battery pack 100 (i.e., an electrode terminal that is liable to be short-circuited), and does not require special sealing properties in other regions of the battery pack 100, thereby reducing the sealing requirements of the battery pack 100, simplifying the manufacturing process of the battery pack 100, and reducing the manufacturing cost of the battery pack 100.

The walls of the first chamber 106 are provided with through holes 109, and the number of through holes 109 is not limited, and generally should be not less than the number of electrode terminals 1042.

To ensure the safety of the battery pack, the first chamber is at least partially insulated.

In order to ensure the tightness of the first chamber 106, the wall of the through hole 109 and the electrode terminal 1042 should be sealed, but the sealing manner is not limited, and in some embodiments, a sealing member 108 is provided between the wall of the through hole 109 and the electrode terminal 1042. The seal 108 may be a rubber ring, a sealant, a filler, or the like.

According to the battery pack 100 provided herein, in some embodiments, the first chamber 106 is provided with the connection member 110, and the connection member 110 is electrically connected to the electrode terminal 1042, thereby achieving electrical connection between the plurality of unit batteries 104.

The connection member 110 is used for connecting two adjacent electrode terminals 1042 (adjacent means adjacent in terms of electrical signals; for example, if A is connected in series with B, then the positive electrode terminal of A and the negative electrode terminal of B are the two adjacent electrode terminals 1042)

The unit cells 104 can be connected in series or in parallel, and if the unit cells 104 are all connected in series, two adjacent unit cells 104 are connected in series through the connecting piece 110; if the unit cells 104 are connected in parallel, two adjacent unit cells 104 are connected in parallel by a connecting member 110.

To achieve better conductivity, the material of the connection member 110 is generally metal, and in some embodiments, the connection member 110 is a copper-aluminum composite connection member, which includes a copper connection portion connected to the negative terminal and an aluminum connection portion connected to the positive terminal, where the contact position of the copper connection portion and the aluminum connection portion is easily corroded under the influence of moisture; sealing the connector 110 in the first chamber 106 can isolate the influence of air and water vapor on the connector 110, avoid insulation failure of the connector 110, and improve the electrical reliability of the battery pack 100.

In some embodiments, in order to facilitate that the position of the connection member 110 is not easy to be changed, and ensure the connection reliability of the connection member 110, the connection member 110 is provided on the cavity wall of the first chamber 106, that is, the cavity wall of the first chamber 106 may function to support and fix the connection member 110.

The manner in which the connection member 110 is disposed on the wall of the first chamber 106 is not particularly limited, as long as it can function to support and fix the connection member 110 to a certain extent. Specifically, a mounting groove 1026 may be provided on a wall of the first chamber 106, and the connecting member 110 is provided in the mounting groove 1026; or the connector 110 may be integrally formed on the wall of the first chamber 106. In some embodiments, an insulating support is provided in the first chamber 106, and the connector 110 is provided on the insulating support.

In some embodiments of the present application, the battery pack 100 further includes a sampling structure (not shown) for monitoring the voltage or current signal of the unit battery 104, and the sampling structure is disposed in the first chamber 106.

The sampling structure is used for collecting current and voltage signals of the battery pack 100, if the current and voltage signals are affected by water vapor and air, the sampling structure of the battery pack 100 is sealed in the first chamber 106, and on the premise that the battery pack 100 is partially sealed, the electrical reliability of the whole battery pack 100 can be improved.

The sampling structure may be a sampling harness or a flexible circuit board (FPC). The sampling structure is mainly used for collecting the voltage, temperature, current and other performances of the battery pack 100.

In some embodiments of the present application, as shown in fig. 2 and 3, the battery pack 100 includes an upper cover 101 and a lower case 102, and the upper cover 101 and the lower case 102 are connected to define a receiving space in which the second chamber 107 is located.

In this embodiment, the first chamber 106 is also located in the accommodation space. That is, the receiving space defined by the connection of the upper cover 101 and the lower case 102 is re-divided into different chambers, wherein one part of the chambers is used to seal the electrode terminals 1042 and the other part of the chambers is used to receive the battery body 1041. Thus, the entire accommodation space is not required to be sealed, and only the space where the electrode terminal 1042 is located is required to be sealed separately. Even if the second chamber 107 where the battery body 1041 is located leaks or enters moisture or the like, the first chamber 106 where the electrode terminal 1042 is located is not affected.

The arrangement of the first chamber 106 is not limited, and may be any arrangement as long as a sealed space is provided.

Specifically, in some embodiments of the present application, a box body (not shown in the drawing) having an opening and a protective cover disposed on the opening of the box body are disposed in the accommodating space defined by the upper cover 101 and the lower housing 102, and the box body is hermetically connected with the protective cover to define the first chamber.

That is, a sealed receiving means, i.e., the receiving means formed of the above-described case and protective cover, may be separately provided in the battery pack 100 to seal the electrode terminals 1042. This is relatively easy to implement and is relatively simple to assemble.

In some embodiments of the present application, as shown in fig. 6, 7, and 9, the battery pack 100 further includes a partition 112, and the partition 112 divides the receiving space into at least one second chamber 107. As shown in fig. 6 and 7, the partition 112 divides the accommodation space into two separate second chambers 107, whereas in fig. 9, the partition divides the accommodation space into one second chamber 107.

As shown in fig. 9, the partition 112 divides the accommodation space into a first chamber 106 and a second chamber 107.

In some embodiments, the baffle 112 is formed internally with the first chamber 106.

In this embodiment, the partition 112 may be provided on the upper cover 101 or the lower case 102, and the partition 112 may be integrally formed with the upper cover 101 or the lower case 102 or may be provided separately.

When the partition 112 is provided on the lower case 102, it can serve as a reinforcing rib of the lower case 102 at the same time; playing a role of strengthening the lower shell.

The number of the partition plates 112 may be plural or may be 1, and the present application is not limited thereto.

The first cavity 106 is formed on the partition 112, and in some embodiments, the partition 112 is hollow to form the first cavity 106, and the hollow portion inside the partition 112 is directly used as the first cavity 106, so that the internal space of the battery pack 100 can be saved, structural members can be reduced, and the space utilization rate of the battery pack 100 can be improved.

In other embodiments, the partition 112 includes a first partition 1121 and a second partition 1122 disposed in a spaced apart relationship, and the first chamber 106 is located between the first partition 1121 and the second partition 1122. The first partition 1121, the second partition 1122, part of the upper cover 101, and part of the lower housing 102 define a first chamber 106, or the first partition 1121, the second partition 1122, and part of the upper cover 101 or part of the lower housing 102 define a receiving groove with a single opening, and an end cover is additionally provided to form the first chamber 106.

Directly using the upper cover 101 or a portion of the lower case 102 as the cavity wall of the first chamber 106 can save structural members and reduce the weight of the battery pack 100.

The number of first separators 1121 may be plural, and the number of second separators 1122 may be plural.

The first separator 1121 and the second separator 1122 divide the accommodating space into a plurality of independent second chambers 107, and the electrode terminals 1042 on the battery body 1041 in two adjacent second chambers 107 may share one first chamber 106, and at this time, through holes 109 through which the power supply terminals 1042 pass are provided in both the first separator 1121 and the second separator 1122; the electrode terminals 1042 on the battery body 1041 in each of the second chambers 107 may be individually sealed in a single first chamber 106, and at this time, through holes 109 through which the electrode terminals 1042 pass may be provided on the first separator 1121 or on the second separator 1122.

Preferably, each of the first and

second separators

1121 and 1122 is provided with a through hole 109 through which the power supply terminal 1042 passes; that is, the electrode terminals 1042 on the battery body 1041 in the adjacent two second chambers 107 may share one first chamber 106, whereby the occupied space of the first chamber 106 may be reduced, providing the space utilization of the battery pack 100; and the use of the separator 112, reduces the weight of the battery pack 100, and additionally facilitates electrical connection between the cells 104.

In some embodiments of the present application, the upper cover 101 is at least partially hollow inside to constitute the first chamber 106; the upper cover 101 and the lower housing 102 are connected to define the second chamber 107.

In this embodiment, the electrode terminal 1042 is directly sealed inside the upper cover 101, that is, the hollow part inside the upper cover 101 is directly used as the first chamber 106 without additionally providing a space for sealing the electrode terminal 1042 inside the battery pack 100, so that the internal space of the battery pack 100 can be saved, structural members can be reduced, and the space utilization of the battery pack 100 can be improved.

In some embodiments of the present application, the lower housing 102 is at least partially hollow inside to form the first chamber 106, and the upper cover 101 and the lower housing 102 are connected to define the second chamber 107.

That is, the electrode terminals 1042 are sealed in the cavity inside the lower case 102 without additionally providing a space for sealing the electrode terminals 1042 in the battery pack 100, the space of the battery pack 100 can be saved, and the energy density of the battery pack 100 can be improved.

In the above embodiment, the lower case 102 includes the bottom plate and the frame 1023 provided around the bottom plate, and the cavity inside the lower case 102 is defined as the first chamber 106, and specifically, the first chamber 106 may be defined by a hollow inside the bottom plate, or the first chamber 106 may be defined by a hollow inside the frame 1023.

Specifically, the position of the first chamber 106 is determined by the orientation of the electrode terminal 1042, for example, when the electrode terminal 1042 faces the bottom plate, the bottom plate may be hollow to form the first chamber 106 for accommodating the electrode terminal 1042, and when the electrode terminal 1042 faces the frame 1023, the first chamber 106 is formed inside the frame 1023 to accommodate the electrode terminal 1042.

In some embodiments, the bezel 1023 is at least partially hollow to form the first chamber 106.

In other embodiments, as shown in fig. 2, the frame 1023 includes an inner frame 1021 and an outer frame 1022, the inner frame 1021 and the outer frame 1022 together defining the first chamber 106.

The inner surface of the inner frame 1021 facing the first chamber 106 is provided with a mounting groove 1026 for mounting the connecting member 110, a through hole 109 is provided in the mounting groove 1026, and the electrode terminals 1042 of the plurality of unit cells 104 pass through the through hole 109 and are electrically connected with the connecting member 110.

In this embodiment, the inner frame 1021 of the lower case 102 serves to support and fix the connection member 110 without providing an additional insulating bracket, so that structural members of the battery pack 100 can be saved and space of the battery pack 100 can be saved.

The outer frame 1022 is covered on the inner frame 1021 to play an insulating protection role.

The inner frame 1021 is a frame on the side closer to the battery body 1041, and the outer frame 1022 is a frame on the side farther from the battery body 1041.

To avoid electrification of the lower housing, the frame is preferably made of an insulating material.

In some embodiments of the present application, the single battery 104 further includes an explosion-proof valve 1043 located on the battery body 1041, a plurality of first through holes 1024 are provided on the inner frame 1021, a plurality of second through holes 1025 are provided on the outer frame 1022, the first through holes 1024 and the second through holes 1025 are oppositely arranged, the explosion-proof valve 1043 is oppositely arranged with the first through holes 1024 and in one-to-one correspondence, and the second through holes 1025 are provided with plugging pieces.

The number of the first vias 1024 is plural, and generally the number of the first vias is consistent with the number of the electrode terminals; the number of the second vias 1025 may be 1 or more.

The explosion-proof valve 1043 of the single battery 104 is disposed corresponding to the first via 1024, and when the gas generated by thermal runaway in the single battery 104 can be directly released to the outside of the battery pack 100 through the first via 1024 and the second via 1025, so as to avoid the gas accumulating in the battery pack 100 and causing a chain reaction.

In order to ensure the sealing performance of the first chamber 106, the explosion-proof valve 1043 and the hole wall of the first via 1024 are provided with sealing members 108, the second via 1025 is provided with a plugging member, and under the condition that the single battery 104 is normal, the second via 1025 is plugged by the plugging member, so that water vapor and dust outside the battery pack 100 cannot enter the first chamber 106 to interfere with the electrode terminal 1042; in the abnormal situation of the single battery 104, such as overcharge or occurrence of internal short circuit, a large amount of gas is instantaneously generated, the internal pressure of the single battery 104 is increased, and the explosion-proof valve 1043 is opened; gas enters the first chamber 106 through the first via 1024 and the closure at the second via 1025 opens, releasing a large amount of gas out of the battery pack 100.

The blocking piece can be a one-way valve or a high-temperature resistant film covering the second via hole.

In some embodiments, as shown in fig. 2, the battery pack 100 further includes a guide cylinder 1027, the guide cylinder 1027 being configured to communicate the explosion protection valve 1043 with the first via 1024; the gas is conveniently discharged from the explosion-proof device and then directly reaches the first through hole 1024 under the guidance of the guide cylinder 1027 to enter the first chamber 106, so that the gas is discharged out of the battery pack 100, and the gas is prevented from being diffused into the battery pack 100 from the gap between the explosion-proof valve 1043 and the first through hole 1024.

Further, the end of the guide cylinder 1027 extends to the second via 1025, that is, the guide cylinder 1027 passes through the first via 1024 to connect the explosion-proof valve 1043 and the second via 1025, thereby directly transmitting the gas discharged from the explosion-proof valve 1043 to the second via 1025, and the sealing member is easy to open, thereby directly discharging the gas to the outside of the battery pack 100, avoiding accumulation of the gas discharged from the explosion-proof valve 1043 in the first chamber 106, and reducing interference of the electrode terminal 1042 and the connection member 110.

In some embodiments of the present application, as shown in fig. 8, the battery body 1041 includes a length L, a thickness D, and a width H, L > h+.gtoreq.d, the electrode terminal 1042 includes a first electrode terminal and a second electrode terminal, the battery body 1041 includes a first end and a second end along a length direction, the first electrode terminal is located at the first end, and the second electrode terminal is located at the second end.

The first electrode terminal and the second electrode terminal, one of which is a positive electrode terminal and the other is a negative electrode terminal, and the "first" and the "second" are used only for distinguishing the electrical properties, and are not used for limiting the number, and the first electrode terminal and the second electrode terminal may be plural.

The first chamber 106 in which the first electrode terminal and the second electrode terminal are located may be different, for example, in several embodiments listed above, the first electrode terminal and the second electrode terminal may be located entirely inside the separator 112, or entirely inside the lower case 102; or the first electrode terminal 1042 is located inside the upper cover 101 and the second electrode terminal is located inside the lower case 102; or the first electrode terminal is located inside the separator 112 and the second electrode terminal is located inside the frame 1023 of the lower case 102.

The first chamber 106 in which the first electrode terminal and the second electrode terminal are located may also be the same, and if the two frames 1023 in which the first electrode terminal and the second electrode terminal are located are connected to each other, the first chamber 106 in which the first electrode terminal and the second electrode terminal are located is the same, as described below.

It should be noted that, as shown in fig. 2, the frame 1023 on the periphery of the bottom plate may be provided with two frames 1023 only in two opposite directions, or the frames 1023 may be provided around the bottom plate, as shown in fig. 6, 7 and 9 (the frames in fig. 6, 7 and 9 are not labeled).

In some embodiments of the present application, the bottom plate is provided with two frames 1023 opposite to each other in the length direction of the bottom plate, one first chamber is provided in each of the two frames 1023, the first electrode terminal corresponds to one of the frames, the second electrode terminal corresponds to the other frame, wherein the first electrode terminal is sealed in the first chamber of the frame corresponding thereto, and the second electrode terminal is sealed in the first chamber of the frame corresponding thereto; the longitudinal direction of the bottom plate coincides with the longitudinal direction of the battery body 1041.

Through this technical scheme, with first electrode terminal and second electrode terminal setting in two frames inside of relative setting simultaneously, not only can realize electrode terminal 1042 sealed function, can also play the positioning action to battery cell 104. That is, the first electrode terminal and the second electrode terminal are provided at two opposite frames 1023, and the fixing function of the unit cells 104 in the battery pack 100 can be directly achieved through the supporting function of the frames 1023 on the unit cells 104, without fixing the unit cells 104 in the battery pack 100 by additional fasteners or an adhesive technique as in the prior art; therefore, the parts of the battery pack 100 can be saved, the cost can be reduced, and the weight of the battery pack 100 can be reduced.

In some embodiments of the present application, as shown in fig. 1, 2, 3, and 5, the upper cover 101 and the lower case 102 abut against the outer surface of the battery body 1041 for restraining expansion of the battery body 1041.

By "against" is understood that the upper cover 101 and the lower housing 102 are pressed against the outer surface of the unit cell 104; the upper cover 101 and the lower case 102 apply a certain pressure to the outer surface of the unit cell 104; it can also be understood that the upper cover 101 and the lower case 102 are simply contacted with the outer surface of the battery body 1041 before the battery is not expanded, and once the unit battery 104 is expanded due to overcharge or internal short circuit, the upper cover 101 and the lower case 102 are respectively pressed against the outer surface of the battery body 1041, thereby restricting the excessive expansion of the battery body 1041, and furthermore, the upper cover 101 and the lower case 102 are simultaneously pressed against the outer surface of the unit battery 104; and also functions to fix the unit cells 104.

In this embodiment, the upper cover 101 and the lower case 102 may be in direct contact with the outer surface of the unit cell 104 or may be in indirect contact with the outer surface of the unit cell; in some embodiments, an insulating protective layer, a temperature resistant layer, or a fireproof material layer is provided between at least one of the upper cover 101 and the lower case 102 and the battery body 1041, and at least one of the upper cover 101 and the lower case 102 is in indirect contact with the outer surface of the battery body 1041.

In some embodiments of the present application, in order to further improve the restraining capability of the upper cover 101 and the lower case 102 when expanding the battery body 1041, as shown in fig. 1, 2, 3 and 5, at least one of the upper cover 101 and the lower case 102 is provided with a reinforcing member 105, and the reinforcing member 105 may improve the strength of the upper cover 101 and the lower case 102 themselves on the one hand and may also improve the expansion restraining capability of the upper cover 101 and the lower case 102 to the battery body 1041 on the other hand.

In this embodiment, the battery body 1041 includes a length L, a thickness D, and a width H, and L > H is equal to or greater than D; a plurality of unit cells 104 are arranged in the width direction of the cell body 1041 to form a cell array; the upper cover 101 and the lower case 102 are disposed opposite to each other in the thickness direction of the battery body 1041.

The two opposite surfaces of the single battery 104 in the thickness direction have larger areas, expansion is easy to occur, the upper cover 101 and the lower housing 102 respectively lean against the surface with the largest area of the battery body 1041, and the expansion constraint effect on the single battery 104 is better.

In some embodiments of the present application, as shown in fig. 1, 2, 3 and 5, in order to improve the heat dissipation capability of the entire battery pack 100, at least one of the upper cover 101 and the lower case 102 is provided with a plurality of protrusions 1011 protruding to the outside of the battery pack 100 at intervals, and an air duct 103 is formed between the protrusions 1011 and the battery body 1041; and at least one of the upper cover 101 and the lower housing 102 is further provided with an air inlet 1031 and an air outlet 1032 which are communicated with the air duct 103.

The concave portions 1012 between the adjacent two convex portions 1011 abut against the outer surface of the battery body 1041.

In this embodiment, a part of the upper cover 101 and the lower case 102 abuts against the outer surface of the battery body 1041, and the other part protrudes outward, so that a gap is formed with the outer surface of the battery body 1041, and the gap constitutes the air duct 103.

When the battery pack 100 is placed on a vehicle, the air duct 103 is preferably consistent with the running direction of the vehicle, and naturally forms convection between the air inlet 1031 and the air outlet 1032, so as to dissipate heat inside the battery pack 100.

In this embodiment, the air duct 103 may be formed only between the upper cover 101 and the battery body 1041, or the air duct 103 may be formed only between the lower case 102 and the battery body 1041; or an air duct 103 is formed between the upper cover 101 and the battery body 1041, and between the lower housing 102 and the battery body 1041; preferably, an air duct 103 is formed between the upper cover 101 and the battery body 1041, and between the lower housing 102 and the battery body 1041; accordingly, heat can be dissipated from both surfaces of the battery body 1041 at the same time, thereby improving heat dissipation efficiency.

Through the above technical scheme, the air duct 103 is formed by utilizing the gap between the upper cover 101 or the lower shell 102 and the outer surface of the battery body 1041 to realize heat dissipation of the battery pack, and an additional fan or a liquid cooling pipeline is not required to be arranged in the battery pack 100, so that the space of the battery pack 100 can be saved, and the space utilization rate of the battery pack 100 can be improved.

In this embodiment, although the air inlet 1031 and the air outlet 1032 are provided on the upper cover 101 and the bottom plate, the entire battery pack 100 is not completely sealed, since the electrode terminal 1042 is sealed in the first chamber 106 alone, even if the second chamber 107 accommodating the battery body 1041 enters moisture or dust from outside the battery pack 100, the electrode terminal 1042 is not affected, so that the terminal is less affected by external environments such as a wading short circuit, etc.

In some embodiments of the present application, the unit cells 104 include two large faces opposing in the thickness direction of the cell body 1041, the plurality of unit cells 104 are arranged in the width direction of the cell body 1041 to form a cell array and the two large faces of the cell body 1041 face the upper cover 101 and the bottom plate, respectively.

In addition, the two large faces of the battery body 1041 are respectively arranged on the upper cover 101 and the bottom plate, an air channel 103 is formed between the two large faces of the battery body 1041 and the upper cover 101 and the bottom plate, the heat dissipation area of the battery body 1041 is larger, and the heat dissipation effect is better.

The projection 1011 may extend along the longitudinal direction of the battery body 1041 or may extend along the width direction of the battery body 1041. There may be a plurality of projections 1011, and there may be a plurality of corresponding air inlets 1031 and air outlets 1032.

In order to make the temperature of the surface of the battery body 1041 relatively uniform; in some embodiments of the present application, the projections 1011 are arranged in the width direction of the battery body 1041. That is, the direction of the cooling air in the air duct 103 extends along the width direction of the battery body 1041, and since the width of the battery body 1041 is smaller, for a certain unit battery 104, the cooling path of the cooling air on the outer surface of the battery body 1041 is shorter, no obvious temperature difference is generated, the temperature of the battery is relatively uniform, and the uniformity is higher.

The temperature difference means that the temperature of the surface near the inlet 1031 is low and the temperature of the surface near the outlet 1032 is high, so that the temperature difference of the surface of the battery body 1041 is large and the internal resistance of the battery is large.

The air duct 103 may be provided with heat dissipation fins to enhance the heat exchange capability between the cooling air and the outer surface of the battery body 1041, and if necessary, a heat-conducting medium may be filled between the heat dissipation fins and the battery body 1041.

In the present application, the upper cover 101 and the lower case 102 are preferably made of thin steel plates, and are manufactured by a sheet metal and press molding process.

In some embodiments of the present application, as shown in fig. 2, a plurality of battery arrays are provided along the thickness direction of the battery body 1041, and adjacent two battery arrays are bonded by the structural adhesive 111.

The main function of the structural adhesive member 111 is to adhere two adjacent layers of battery arrays to limit the displacement of each battery array bracket and improve the shock resistance; the structural adhesive member 111 may be one of a heat-conducting adhesive, a structural adhesive or a double-sided adhesive, preferably, the structural adhesive member 111 is made of an adhesive with a heat-conducting function, and the adjacent battery array members on two sides can mutually transfer heat, so that the heat resistance of each layer from top to bottom is minimized, and the temperature consistency of the single battery 104 is improved.

In some embodiments of the present application, the length and thickness of the battery body 1041 satisfy: l is more than or equal to 400mm and less than or equal to 2500mm, and L/D is more than or equal to 10 and less than or equal to 208.

The battery body is long, so that the battery pack 100 can be reinforced, and in addition, the length and thickness of the battery body 1041 are limited to the above range, and the unit battery 104 is properly flattened, so that the air duct 103 can be more conveniently arranged, and the heat dissipation effect of the battery pack 100 is better.

In the present application, the battery body 1041 includes a length L, a thickness D, and a width H, where L > H is greater than or equal to D, and it can be understood that the unit battery is substantially rectangular or has a local special shape, but is substantially rectangular; or, some of the grooves, protrusions, chamfers, radians and curves exist, but the whole is approximately cuboid.

In a second aspect of the present application, an electric vehicle is provided that includes any of the battery packs 100 described above. With the battery pack 100 provided by the application, the safety performance of the electric vehicle is better.

In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

In the description herein, reference to the terms "embodiment," "specific embodiment," "example," and the like, means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that: many variations, modifications, and substitutions may be made to the embodiments without departing from the spirit and principles of the invention.

Claims

1. A battery pack, comprising:

a first chamber and a second chamber, the first chamber being a sealed chamber;

the battery comprises a plurality of single batteries, a plurality of battery modules and a plurality of battery modules, wherein each single battery comprises a battery body and an electrode terminal which is arranged on the battery body and used for leading out current;

a through hole is formed in the cavity wall of the first cavity, at least part of the electrode terminal penetrates through the through hole and is sealed in the first cavity, and the battery body is positioned in the second cavity;

the battery pack includes an upper cover and a lower case connected to define an accommodating space in which the second chamber is located;

the lower shell comprises a bottom plate and a frame arranged on the periphery of the bottom plate, and the frame is at least partially hollow to form the first chamber;

the frame comprises an inner frame and an outer frame, and the inner frame and the outer frame jointly define the first chamber;

the inner frame of the lower shell is used for supporting and fixing a connecting piece, and the connecting piece is used for being electrically connected with two electrode terminals of adjacent single batteries.

2. The battery pack according to claim 1, wherein a sealing member is provided between the wall of the through hole and the electrode terminal.

3. The battery pack of claim 1, wherein a connector is disposed within the first chamber, the connector electrically connecting the electrode terminals.

4. A battery pack as claimed in claim 3, wherein the connector is provided on a wall of the first chamber.

5. A battery pack as in claim 3, wherein an insulating support is further provided in the first chamber, and the connector is provided on the insulating support.

6. The battery pack of claim 1, further comprising a sampling structure for monitoring a cell voltage or current signal, the sampling structure disposed in the first chamber.

7. The battery pack of claim 1, wherein the first chamber is located in the receiving space.

8. The battery pack of claim 1, wherein the through hole is provided on the inner frame.

9. The battery pack according to claim 1, wherein the single battery further comprises an explosion-proof valve positioned on the battery body, a plurality of first through holes are formed in the inner frame, a plurality of second through holes are formed in the outer frame, the explosion-proof valve is arranged opposite to and in one-to-one correspondence with the first through holes, and plugging pieces are arranged at the second through holes.

10. The battery pack of claim 9, further comprising a guide cylinder for communicating the explosion-proof valve with the first via.

11. The battery pack of claim 10, wherein an end of the guide cylinder extends to the second via.

12. The battery pack of claim 1, wherein the battery body comprises a length L, a thickness D, and a width H, and L > H is ≡d; the electrode terminals include a first electrode terminal and a second electrode terminal, the battery body includes a first end and a second end along a length direction, the first electrode terminal is located at the first end, and the second electrode terminal is located at the second end.

13. The battery pack according to claim 12, wherein the bottom plate is provided with two frames opposite to each other in a length direction of the bottom plate, the first electrode terminal is sealed in a first chamber of one of the frames, and the second electrode terminal is sealed in a first chamber of the other frame; the length direction of the bottom plate is consistent with the length direction of the battery body.

14. The battery pack of claim 1, wherein the upper cover and the lower case abut against an outer surface of the battery body to restrain expansion of the battery body.

15. The battery pack of claim 14, wherein at least one of the upper cover and the lower case is provided with a reinforcement.

16. The battery pack of claim 14, wherein the battery body comprises a length L, a thickness D, and a width H, and L > H ≡d; the plurality of unit cells are arranged along the width direction of the cell body to form a cell array; the upper cover and the lower case are disposed opposite to each other in the thickness direction of the battery body.

17. The battery pack according to claim 1, wherein at least one of the upper cover and the lower case is provided with a plurality of protrusions protruding to the outside of the battery pack at intervals, and an air duct is formed between the protrusions and the battery body;

and at least one of the upper cover and the lower shell is also provided with an air inlet and an air outlet which are communicated with the air duct.

18. The battery pack of claim 17, wherein the recess between two adjacent protrusions abuts against the outer surface of the battery body.

19. The battery pack of claim 18, wherein the battery body comprises a length L, a thickness D, and a width H, and L > H ≡d; the plurality of unit cells are arranged along the width direction of the cell body to form a cell array; the upper cover and the lower shell are oppositely arranged in the thickness direction of the battery body;

the protruding parts extend along the width direction of the battery body, and the plurality of protruding parts are arranged along the length direction of the battery body.

20. The battery pack according to claim 13 or 16, wherein a plurality of battery arrays are provided in a thickness direction of the battery body, and adjacent two battery arrays are bonded by a structural adhesive member.

21. The battery pack of claim 12, 16 or 19, wherein the length and thickness of the battery body satisfy: l is more than or equal to 400mm and less than or equal to 2500mm, and L/D is more than or equal to 10 and less than or equal to 208.

22. An electric vehicle comprising the battery pack of any one of claims 1-21.