Lithium ion battery

Abstract

The utility model provides a lithium ion battery, relates to the technical field of batteries, and aims to realize the high-voltage characteristic of the lithium ion battery to a certain extent and ensure the safety of the battery. The utility model provides a lithium ion battery. The lithium ion battery comprises a shell, a cover plate and a battery cell, the shell comprises a main body part and a plurality of separation parts, the plurality of separation parts are arranged in the main body part at intervals and form a plurality of separation cavities, and the battery cells and the separation cavities are arranged in a one-to-one correspondence manner; an opening is formed in the shell, the cover plate covers the opening in a sealing mode, a through hole is formed in the position, corresponding to the partition cavity, of the cover plate, and a tab of the battery cell penetrates through the cover plate through the through hole.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a lithium-ion battery. Background Technology

[0002] With the development of new energy vehicles, the performance requirements for batteries are becoming increasingly stringent. Since a key characteristic of pure electric vehicles is their high voltage, which is susceptible to breakdown due to environmental changes or improper operation during use, leading to battery safety issues, current methods to ensure high-voltage performance primarily involve coating the inner wall of the battery casing with insulating material to achieve a certain degree of insulation between the multiple cells.

[0003] However, applying insulating coating cannot guarantee the uniformity and complete coverage of the coating, which may result in the cells not being properly separated except for the tabs.

[0004] Therefore, there is an urgent need to provide a lithium-ion battery that can, to some extent, solve the problems existing in the current technology. Utility Model Content

[0005] The purpose of this invention is to provide a lithium-ion battery that optimizes the lithium-ion battery structure to a certain extent, achieves high voltage characteristics, and ensures battery safety.

[0006] This utility model provides a lithium-ion battery, including a casing, a cover plate, and a battery cell; the casing includes a main body and multiple partitions, the multiple partitions are spaced apart in the main body and form multiple partition cavities, and the battery cell is arranged in a one-to-one correspondence with the partition cavity; the casing has an opening, the cover plate covers the opening, and the cover plate has a perforation at the position corresponding to the partition cavity, and the electrode tab of the battery cell passes through the perforation through the cover plate.

[0007] Both the cover plate and the housing are made of plastic, and the cover plate is a one-piece structure.

[0008] Specifically, the cover plate is composed of multiple slats, and each of the multiple slats is arranged in a one-to-one correspondence with the partition cavity.

[0009] Furthermore, the housing has a mating portion formed at the edge of the opening of the partition cavity, the mating portion being formed circumferentially along the opening of the partition cavity, the slat portion being able to overlap the mating portion, and the slat portion being sealed to the housing.

[0010] Furthermore, a first sealing layer is formed on the edge of the slat portion corresponding to the position of the mating portion, and the first sealing layer is disposed along the circumference of the slat portion.

[0011] The perforation includes a first perforation and a second perforation. The positive electrode tab of the battery cell passes through the slat portion through the first perforation, and the negative electrode tab of the battery cell passes through the slat portion through the second perforation. The first perforation and the second perforation in two adjacent slat portions correspond to each other, so that the positive electrode tabs of two adjacent battery cells correspond to the negative electrode tabs.

[0012] Specifically, the lithium-ion battery provided by this utility model further includes a first connecting piece and a second connecting piece. The first connecting piece is connected to the first through hole, and the second connecting piece is connected to the second through hole. One end of both the first connecting piece and the second connecting piece is located in the partition cavity, and the other end protrudes from the cover plate on the side away from the shell. The first connecting piece is connected to the positive electrode tab, and the second connecting piece is connected to the negative electrode tab. Both the first connecting piece and the second connecting piece have a flat structure.

[0013] Furthermore, the first connecting piece is made of aluminum alloy, and the second connecting piece is made of copper, copper alloy, copper-nickel alloy, or aluminum alloy.

[0014] Furthermore, a second sealing layer is formed on the outer wall surface of the first connecting piece and the second connecting piece, and the second sealing layer is connected to the strip portion.

[0015] Compared with existing technologies, the lithium-ion battery provided by this utility model has the following advantages:

[0016] The lithium-ion battery provided by this utility model includes a casing, a cover plate, and a battery cell; the casing includes a main body and multiple partitions, the multiple partitions are spaced apart in the main body and form multiple partition cavities, and the battery cell is arranged in a one-to-one correspondence with the partition cavity; the casing has an opening, the cover plate covers the opening, and the cover plate has a perforation at the position corresponding to the partition cavity, and the battery cell's tab passes through the cover plate through the perforation.

[0017] This analysis shows that by setting multiple partitions in the main body of the housing, the space inside the housing can be divided into multiple partition cavities. By setting the battery cells and partition cavities one by one, adjacent battery cells can be separated by the partitions, thereby ensuring the independence of each battery cell in the housing.

[0018] Furthermore, since this application also includes a cover plate that can cover the opening of the casing, and the cover plate has perforations at the positions corresponding to the tabs of the cells, the cover plate connected to the casing can, on the one hand, form a sealed space with the casing to achieve electrolyte filling and stable cell installation; on the other hand, by allowing the tabs of the cells to protrude through the perforations of the casing, all positions of all cells in the casing except for the tabs can be separated, thereby further improving the independence of the cells, increasing the degree of separation between cells, achieving high voltage characteristics, and improving battery safety. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the overall structure of a lithium-ion battery provided in an embodiment of the present invention;

[0021] Figure 2 This is a schematic diagram of the structure of the casing in a lithium-ion battery provided in an embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the overall structure of the cover plate in a lithium-ion battery provided in an embodiment of the present invention;

[0023] Figure 4 An exploded view of the slatted section and the explosion-proof valve in a lithium-ion battery provided in an embodiment of this utility model;

[0024] Figure 5 A schematic diagram showing the connection between the strip portion and the first connecting piece and the second connecting piece in a lithium-ion battery provided in an embodiment of this utility model;

[0025] Figure 6 This is an exploded view of the cell and slat portion in a lithium-ion battery provided in an embodiment of the present invention;

[0026] Figure 7 for Figure 6 A magnified view of a section at point A in the middle;

[0027] Figure 8 This is a schematic diagram showing the overlap between the slat portion and the casing in a lithium-ion battery provided in an embodiment of the present invention.

[0028] In the figure: 1-shell; 101-main body; 102-separation part; 1021-fitting part; 103-separation cavity; 2-cell; 201-positive electrode tab; 202-negative electrode tab; 3-cover plate; 301-slat part; 3011-first perforation; 3012-second perforation; 3013-mounting groove; 4-first connecting piece; 5-second connecting piece; 6-sealing layer; 7-explosion-proof valve. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0030] In the description of the embodiments of this application, it should be noted that the terms "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use. They are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the utility model. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0031] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0032] In the description of the embodiments of this application, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0033] As used herein, the term “and / or” includes any one of the relevant items listed and any combination of any two or more items.

[0034] For ease of description, spatial relation terms such as “above,” “upper,” “below,” and “lower” may be used herein to describe the relationship between one element and another as shown in the accompanying drawings. Such spatial relation terms are intended to include not only the orientation depicted in the drawings but also the different orientations of the device during use or operation.

[0035] The terminology used herein is for the purpose of describing various examples only and is not intended to limit this disclosure. Unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. The terms “comprising,” “including,” and “having” enumerate the stated features, quantities, operations, components, elements, and / or combinations thereof, but do not exclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof.

[0036] Variations in the shapes shown in the accompanying drawings may occur due to manufacturing techniques and / or tolerances. Therefore, the examples described herein are not limited to the specific shapes shown in the accompanying drawings, but include changes in shape that may occur during manufacturing.

[0037] The features of the examples described herein can be combined in various ways that will be apparent upon understanding the disclosure of this application. Furthermore, although the examples described herein have various constructions, other constructions are possible, as will be apparent upon understanding the disclosure of this application. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis that they can be implemented by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0038] like Figures 1-3As shown, this utility model provides a lithium-ion battery, including a casing 1, a cover plate 3, and a battery cell 2; the casing 1 includes a main body 101 and a plurality of partitions 102, the plurality of partitions 102 are spaced apart in the main body 101 and form a plurality of partition cavities 103, the battery cell 2 is arranged in a one-to-one correspondence with the partition cavities 103; the casing 1 has an opening, the cover plate 3 covers the opening, and the cover plate 3 has a perforation at the position corresponding to the partition cavity 103, the electrode tab of the battery cell 2 passes through the perforation through the cover plate 3.

[0039] Compared with existing technologies, the lithium-ion battery provided by this utility model has the following advantages:

[0040] The lithium-ion battery provided by this utility model can divide the space inside the housing 1 into multiple partition cavities 103 by providing multiple partitions 102 inside the main body 101 of the housing 1. By making the battery cell 2 correspond one-to-one with the partition cavity 103, the partitions 102 can separate adjacent battery cells 2, thereby ensuring the independence of each battery cell 2 inside the housing 1.

[0041] Furthermore, since this application also includes a cover plate 3, which can cover the opening of the housing 1, and has perforations on the cover plate 3 corresponding to the tab positions of the battery cell 2, the cover plate 3 connected to the housing 1 can, on the one hand, form a sealed space with the housing 1 to achieve electrolyte filling and stable installation of the battery cell 2; on the other hand, by allowing the tabs of the battery cell 2 to pass through the perforations of the housing 1, it can achieve separation of all positions of the battery cells 2 inside the housing 1 except for the tabs, thereby further improving the independence of the battery cell 2, increasing the degree of separation between the battery cells 2, achieving high voltage characteristics, and improving battery safety.

[0042] It should be noted that the partition 102 and the main body 101 in this application can be integrally formed, or the partition 102 and the main body 101 can be connected by welding. Furthermore, the multiple partitions 102 in this application are spaced at the same intervals and arranged parallel to each other, thereby ensuring that the dimensions of each partition cavity 103 are consistent, thus achieving stable support for the battery cell 2.

[0043] It is understood that the housing 1 with the partition cavity 103 provided in this application can also achieve further isolation between the battery cells 2 by coating an insulating layer. Preferably, the cover plate 3 and the housing 1 in this application are both made of plastic.

[0044] The plastic housing 1 and cover plate 3 not only have good insulation properties, making the separation between the battery cells 2 more thorough, but also have lower cost, simpler processing, easier connection between the cover plate 3 and housing 1, and lighter weight.

[0045] The cover plate 3 in this application can be an integral structure, which can improve the overall structural strength of the cover plate 3 to a certain extent.

[0046] It should be noted that, since electrolyte needs to be injected into the cavity after the shell 1 and cover plate 3 are sealed together in this application, the plastic in this application can be an electrolyte-resistant plastic, which can be polypropylene, polyethylene terephthalate, polyphenylene sulfide or modified polypropylene, modified polyethylene terephthalate, modified polyphenylene sulfide, etc.

[0047] Accordingly, both the shell 1 and the cover plate 3 in this application can be injection molded.

[0048] It should be further noted that the cover plate 3 in this application can also be made of modified laser-transparent plastic, thereby enabling laser welding between the cover plate 3 and the housing 1. To further improve the positioning effect of the housing 1 on the cover plate 3, a stepped portion can be formed at the edge of the housing 1, thereby forming a rectangular fixing groove for positioning the cover plate 3.

[0049] Optionally, the cover plate 3 in this application can be as follows: Figure 3 The monolithic structure shown can also be as follows: Figure 1 Combination Figure 4 The diagram shows a combination of multiple slat sections 301, with each slat section 301 corresponding to a partition cavity 103.

[0050] It is understandable that by making the cover plate 3 composed of multiple slats 301, when one or more slats 301 are damaged or the internally encapsulated battery cells 2 need to be inspected and replaced, the corresponding slats 301 can be removed individually to complete the corresponding operation without replacing or repairing the whole system. This can save on maintenance and replacement costs to a certain extent and improve work efficiency.

[0051] Optionally, such as Figure 8 As shown, in this application, the housing 1 has a mating part 1021 formed at the edge of the opening of the partition cavity 103. The mating part 1021 is formed circumferentially along the opening of the partition cavity 103. The strip part 301 can overlap the mating part 1021 and the strip part 301 is sealed to the housing 1.

[0052] In this application, the sealing connection between the slat portion 301 and the housing 1 can be achieved by welding methods such as laser welding, hot melt welding, ultrasonic welding, and chemical welding.

[0053] It is understood that, since the main body 101 in this application is provided with multiple partitions 102, and the aforementioned mating parts 1021 are formed circumferentially along the opening of the partition cavity 103, the mating parts 1021 in this application are not only formed in such... Figure 8 The end position of the partition 102 shown is also formed on the edge of the housing 1. That is, when the partition cavity 103 is located in the middle position of the housing 1, the mating part 1021 is formed on the end of the two adjacent partitions 102 and the end face of the two parallel side walls of the housing 1, thereby forming a rectangular positioning groove to position the slat part 301 located in the middle position.

[0054] When the partition cavity 103 is located at the edge of the housing 1, the mating part 1021 is formed on the end of the partition part 102 and the end face of the three side walls of the housing 1, thereby forming a rectangular positioning groove to position the strip part 301 located at the edge.

[0055] Optionally, a sealing layer is formed at the edge of the slat portion 301 corresponding to the position of the mating portion 1021 in this application, and the sealing layer is disposed along the circumference of the slat portion 301.

[0056] Since the cover plate 3 in this application needs to be sealed to the housing 1, a sealing layer formed at the edge of the strip portion 301 corresponding to the mating portion 1021 can achieve a sealed connection between the strip portion 301, the main body portion 101, and the partition portion 102.

[0057] The connecting layer in this application can be formed by a colloid or other viscous material that is easy to melt. Therefore, when it is necessary to achieve a sealed connection between the strip portion 301 and the main body portion 101 and the partition portion 102, the connecting layer can be melted by means of heat melting, thereby achieving a sealed connection between the strip portion 301 and the main body portion 101 and the partition portion 102.

[0058] Optionally, such as Figures 3-7 As shown, the perforation includes a first perforation 3011 and a second perforation 3012. The positive electrode tab 201 of the battery cell 2 passes through the strip portion 301 through the first perforation 3011, and the negative electrode tab 202 of the battery cell 2 passes through the strip portion 301 through the second perforation 3012. The first perforation 3011 and the second perforation 3012 in two adjacent strip portions 301 correspond to each other, so that the positive electrode tab 201 and the negative electrode tab 202 of two adjacent battery cells 2 correspond to each other.

[0059] Since a battery cell 2 will have a positive electrode tab 201 and a negative electrode tab 202, by forming a first through hole 3011 and a second through hole 3012 on the strip portion 301, the positive electrode tab 201 and the negative electrode tab 202 of the battery cell 2 can be accurately matched, thereby ensuring the stable installation of the battery cell 2 and the positive electrode tab 201 and the negative electrode tab 202 of the battery cell 2.

[0060] It is understandable that, since the positive electrode tab 201 and the negative electrode tab 202 in two adjacent cells 2 are connected in series, therefore, as Figure 3 As shown, when multiple strip sections 301 are installed, in two adjacent strip sections 301, the first through hole 3011 of one strip section 301 corresponds to the second through hole 3012 of the other strip section 301, and the second through hole 3012 corresponds to the first through hole 3011 of the other strip section 301. This makes the positive electrode tab 201 and negative electrode tab 202 of two adjacent cells 2 closer in position after passing through the strip section 301, thereby enabling the positive electrode tab 201 and negative electrode tab 202 to be connected in series.

[0061] It should be noted that in this application, a single partition cavity 103 can accommodate one or more battery cells 2. When there are multiple battery cells 2 in a partition cavity 103, the multiple battery cells 2 are connected in parallel. After being connected in parallel, they form a unified positive electrode tab 201 and a negative electrode tab 202 that pass through the strip section 301 and are then connected in series to form an integral lithium-ion battery.

[0062] Optionally, such as Figures 5-7 As shown, the lithium-ion battery provided by this utility model also includes a first connecting piece 4 and a second connecting piece 5. The first connecting piece 4 is connected to the first through hole 3011, and the second connecting piece 5 is connected to the second through hole 3012. One end of the first connecting piece 4 and the second connecting piece 5 are both located in the partition cavity 103, and the other end protrudes from the side of the cover plate 3 away from the shell 1. The first connecting piece 4 is connected to the positive electrode tab 201, and the second connecting piece 5 is connected to the negative electrode tab 202. The first connecting piece 4 and the second connecting piece 5 are both flat structures. The flat first connecting piece 4 and the second connecting piece 5 can be used as pole posts or as external connecting piece structures for the series and parallel connection of the battery cells 2.

[0063] Since the positive electrode tab 201 and negative electrode tab 202 of the battery cell 2 are integrated and welded together, the overall size after welding is limited. By installing the first connecting piece 4 in the first through hole 3011 and placing one end of the first connecting piece 4 in the partition cavity 103, it is easy to connect with the positive electrode tab 201. Correspondingly, by installing the second connecting piece 5 in the second through hole 3012 and placing one end of the second connecting piece 5 in the partition cavity 103, it is easy to connect with the negative electrode tab 202, thereby achieving the purpose of extending the positive electrode tab 201 and the negative electrode tab 202 outward from the strip portion 301.

[0064] It should be noted that the first connecting piece 4 and the positive electrode tab 201, as well as the second connecting piece 5 and the negative electrode tab 202 in this application, can be achieved by ultrasonic welding or laser welding.

[0065] Preferably, the first connecting piece 4 in this application is made of aluminum alloy, and the second connecting piece 5 is made of copper, copper alloy or aluminum alloy, and more preferably pure copper or copper plated with nickel, with a nickel layer thickness of 1μm-20μm.

[0066] Optionally, a sealing layer 6 is also formed on the outer wall surface of the first connecting piece 4 and the second connecting piece 5 in this application, and the sealing layer 6 is connected to the strip portion 301.

[0067] In this application, the sealing layer 6 can be a plastic layer, which is connected to the strip portion 301 by means of hot melt welding or chemical welding. Alternatively, the sealing layer 6 can be an adhesive layer, which is used to bond the strip portion 301 to the strip portion.

[0068] Since electrolyte needs to be added into the casing 1 to form a lithium-ion battery, in order to prevent electrolyte from overflowing from the positions of the first connecting piece 4 and the second connecting piece 5, i.e. the first perforation 3011 and the second perforation 3012, this application forms a sealing layer 6 on the outer wall surface of the first connecting piece 4 and the second connecting piece 5. This sealing layer 6 can achieve a sealed connection between the first connecting piece 4 and the first perforation 3011 and between the second connecting piece 5 and the second perforation 3012, thus ensuring the sealing performance and stability of the overall lithium-ion battery.

[0069] Optionally, such as Figure 4 As shown, the lithium-ion battery provided by this utility model also includes an explosion-proof valve 7. An installation groove 3013 is formed on the plate portion 301, the explosion-proof valve 7 is disposed in the installation groove 3013, and the explosion-proof valve 7 is sealed to the plate portion 301.

[0070] The mounting groove 3013 formed on the slat portion 301 provides a stable mounting position for the explosion-proof valve 7. By setting the explosion-proof valve 7, pressure can be released in time when the battery experiences thermal runaway, thus avoiding the risk of battery explosion to a certain extent.

[0071] Preferably, the explosion-proof valve 7 in this application is an explosion-proof membrane, which is made of polyolefin and can be laser welded or hot-pressed to the strip portion 301.

[0072] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A lithium-ion battery, characterized in that, Includes the casing, cover plate, and battery cell; The housing includes a main body and a plurality of partitions, the plurality of partitions being spaced apart within the main body and forming a plurality of partition cavities, and the battery cells being disposed in a one-to-one correspondence with the partition cavities; The housing has an opening, the cover plate seals the opening, and the cover plate has a perforation corresponding to the position of the partition cavity, through which the electrode of the battery cell passes.

2. The lithium-ion battery according to claim 1, characterized in that, Both the cover plate and the housing are made of plastic, and the cover plate is a one-piece structure.

3. The lithium-ion battery according to claim 1, characterized in that, The cover plate is composed of multiple slats, and each of the multiple slats is arranged in a one-to-one correspondence with the partition cavity.

4. The lithium-ion battery according to claim 3, characterized in that, The housing has a mating part formed at the edge of the opening of the partition cavity. The mating part is formed circumferentially along the opening of the partition cavity. The slat part can overlap the mating part and is sealed to the housing.

5. The lithium-ion battery according to claim 4, characterized in that, A first sealing layer is formed on the edge of the slat portion corresponding to the position of the mating portion, and the first sealing layer is disposed along the circumference of the slat portion.

6. The lithium-ion battery according to claim 3, characterized in that, The perforation includes a first perforation and a second perforation. The positive electrode tab of the battery cell passes through the slat portion through the first perforation, and the negative electrode tab of the battery cell passes through the slat portion through the second perforation. The first perforation and the second perforation in two adjacent slat portions correspond to each other, so that the positive electrode tabs of two adjacent battery cells correspond to the negative electrode tabs.

7. The lithium-ion battery according to claim 6, characterized in that, It also includes a first connecting piece and a second connecting piece. The first connecting piece is connected to the first through hole, and the second connecting piece is connected to the second through hole. One end of the first connecting piece and the second connecting piece are both located in the partition cavity, and the other end protrudes from the side of the cover plate away from the housing. The first connecting piece is connected to the positive electrode tab, and the second connecting piece is connected to the negative electrode tab. Both the first connecting piece and the second connecting piece have a flat structure.

8. The lithium-ion battery according to claim 7, characterized in that, The first connecting piece is made of aluminum alloy, and the second connecting piece is made of copper, copper alloy, copper-nickel alloy, or aluminum alloy.

9. The lithium-ion battery according to claim 7, characterized in that, A second sealing layer is also formed on the outer wall surface of the first connecting piece and the second connecting piece, and the second sealing layer is connected to the strip portion.

10. The lithium-ion battery according to claim 3, characterized in that, It also includes an explosion-proof valve, wherein an installation groove is formed on the slat portion, the explosion-proof valve is disposed in the installation groove, and the explosion-proof valve is sealed to the slat portion.

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