CN111129367A

CN111129367A - Energy storage device and assembling method thereof

Info

Publication number: CN111129367A
Application number: CN201911403033.XA
Authority: CN
Inventors: 童焰; 陈志勇
Original assignee: Guangdong Mic Power New Energy Co Ltd
Current assignee: Guangdong Mic Power New Energy Co Ltd
Priority date: 2019-12-30
Filing date: 2019-12-30
Publication date: 2020-05-08
Also published as: WO2021135165A1

Abstract

The invention discloses an energy storage device and an assembly method of the energy storage device. The energy storage device comprises an energy conversion element and a shell; the energy conversion element has at least one electrical connection disposed on a surface thereof; the shell comprises a conductor layer and at least one insulating layer which are compounded together, a cavity is formed in the shell, the at least one insulating layer is positioned on one side of the cavity, a hollow structure is arranged on the insulating layer positioned on one side of the cavity, the conductor layer is exposed in the hollow structure to form a contact part, and the electric connection part is connected with the contact part; the shell comprises a first half shell and a second half shell which are connected together in a sealing mode, wherein at least one of the first half shell and the second half shell comprises a sunken structure and an edge part formed by outwards extending edges of the sunken structure; the hollow structure is arranged on the concave structure. The energy storage device is simple in structure and easy to realize edge sealing and bending.

Description

Energy storage device and assembling method thereof

Technical Field

The invention relates to the technical field of energy storage devices, in particular to an energy storage device and an assembly method of the energy storage device.

Background

The energy storage device includes, for example, a battery, a capacitor, and the like. Batteries are generally required to be arranged in electronic products, and the batteries are used for supplying power to realize normal use of electronic equipment. The battery used in the electronic product may be, for example, a steel-can battery or a pouch battery.

Existing pouch cells typically include a jellyroll and two half shells that snap together, the jellyroll being assembled into the space enclosed by the two half shells. Two utmost point ears of book core are outwards stretched out from the edge of two half shells and are used for carrying out the electricity and connect, and this just leads to the battery to have the comparatively difficult problem of banding buckle, leads to the packaging film damaged easily and produces the weeping phenomenon. Even the overall sealing performance of the battery may be affected, resulting in reduced waterproof and dustproof performance. If the naked electric core in the soft-packaged button battery is the coiling formula structure, utmost point ear lead-out angle is unstable, then is more difficult for carrying out the banding buckle, also is difficult to realize automated production. And the tab is bent and then subjected to heat sealing treatment, so that the sealing difficulty is increased, the space utilization rate of the battery is possibly influenced, and the energy density of the battery is reduced.

Although the assembly process of the steel-shell battery is simpler, the safety performance of the steel-shell battery is poorer. Moreover, the steel shell also has the defects of heavy weight, small distance between the positive electrode and the negative electrode and easy short circuit.

Therefore, it is necessary to provide a new technical solution to solve the above technical problems.

Disclosure of Invention

An object of the present invention is to provide a new solution for an energy storage device and a method of assembling an energy storage device.

According to a first aspect of the present invention, there is provided an energy storage device comprising:

an energy conversion element having at least one electrical connection disposed on a surface thereof; and

the shell comprises a conductor layer and at least one insulating layer which are compounded together, a cavity is formed in the shell, the at least one insulating layer is positioned on one side of the cavity, a hollow structure is arranged on the insulating layer positioned on one side of the cavity, the conductor layer is exposed in the hollow structure to form a contact part, and the electric connection part is connected with the contact part;

the shell comprises a first half shell and a second half shell which are connected together in a sealing mode, wherein at least one of the first half shell and the second half shell comprises a sunken structure and an edge part formed by outwards extending edges of the sunken structure; the hollow structure is arranged on the concave structure.

Optionally, the edge portions are welded together by heat fusion or ultrasound.

Optionally, the hollow structure is formed by a material removing treatment.

Optionally, after the first half shell and the second half shell are hermetically connected, the first half shell and the second half shell are folded up and down, and the edge part is folded towards the side wall of the shell.

Optionally, the insulating layer is made of plastic.

Optionally, the conductor layer includes an inner surface located on one side of the cavity and an outer surface opposite to the inner surface, the insulating layers are compounded on the inner surface and the outer surface, and the hollow structures are formed at corresponding positions of the two insulating layers.

Optionally, the energy conversion element comprises an energy conversion element body and the electrical connection portion mechanically connected to the energy storage element body, or the electrical connection portion is a portion of the energy storage element body extending over a surface thereof.

Optionally, the energy conversion element is a winding type bare cell or a laminated type bare cell.

Optionally, the electrical connection portion is welded to an inner surface of the contact portion;

when welding, a welding point or a welding bead passes through the contact part from the outer side of the shell; or

The welding spots or welding beads gradually spread to the periphery from the contact surface of the contact part and the electric connection part.

Optionally, the energy storage device is a pouch battery.

According to a second aspect of the present invention, there is provided an assembly method of an energy storage device, the energy storage device including:

the shell comprises a conductor layer and at least one insulating layer which are compounded together, a cavity is formed in the shell, the at least one insulating layer is positioned on one side of the cavity, a hollow structure is arranged on the insulating layer positioned on one side of the cavity, and the conductor layer is exposed in the hollow structure to form a contact part;

the assembling method comprises the following steps:

placing the energy conversion element into the cavity;

vacuumizing the shell, and pressing the contact part by using atmospheric pressure to enable the contact part to be in contact with the electric connection part; and

and closing the shell.

Optionally, the electrical connection is separated from the contact portion when the air pressure within the cavity is above atmospheric pressure.

According to one embodiment of the disclosure, in the energy storage device, the electrical connection part does not need to extend outwards from the edge of the two half shells, and the two half shells are convenient to form a good sealing connection. The hollow structure is formed by digging holes in the shell, the conductor layer of the shell is exposed from the hollow structure, so that the internal energy conversion element can be directly electrically connected with the outside through the conductor layer of the shell, the structure of the energy storage device is simplified, and the problem that the battery edge sealing and bending are difficult due to the fact that the electric connection part is led out is avoided. Meanwhile, the welding of the electric connection part on the energy conversion element can adopt a steel shell battery welding technology, the battery shell can take account of the characteristics of the soft package battery shell, and the safety and the assembly process of the battery are obviously improved. The technical task to be achieved or the technical problems to be solved by the present invention are never thought or not expected by those skilled in the art, and therefore the present invention is a new technical solution.

Other features of the present invention and advantages thereof will become apparent from the following detailed description of exemplary embodiments thereof, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention.

Fig. 1 is a perspective view of an energy storage device provided according to one embodiment of the present disclosure.

Fig. 2 is a side view of fig. 1.

Fig. 3 is a perspective view of an energy storage device provided in accordance with another embodiment of the present disclosure.

Fig. 4 is a top view of fig. 3.

Fig. 5 is an exploded view of an energy storage device provided in accordance with an embodiment of the present disclosure.

Fig. 6 is a side view of fig. 5.

Fig. 7 is a schematic structural diagram of an energy storage device provided according to an embodiment of the present disclosure.

Fig. 8 is a cross-sectional view of an energy storage device provided according to one embodiment of the present disclosure.

Description of reference numerals:

1-shell, 11-first half shell, 12-second half shell, 13-edge part, 14-conductor layer, 15-insulating layer, 2-hollow structure, 3-energy conversion element, 31-electric connection part and 32-core column.

Detailed Description

Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise.

The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate.

In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

According to one embodiment of the present disclosure, an energy storage device is provided. The energy storage device may be, for example, a battery or a capacitor. When the energy storage device is a battery, it may be a soft package battery, or a steel-shell battery, for example. The battery may be a primary battery or a secondary battery. The energy storage device provided by the embodiment of the invention can be applied to various types of electronic equipment and can be used for supplying power to the electronic equipment so as to realize normal use of the electronic equipment.

An energy storage device according to an embodiment of the present invention, as shown in fig. 1 to 8, includes an energy conversion element 3 and a housing 1. Wherein the energy conversion element 3 has at least one electrical connection 31 provided on its surface. The shell 1 comprises a conductor layer 14 and at least one insulating layer 15 which are compounded together, a cavity is formed in the shell 1, at least one insulating layer 15 is located on one side of the cavity, a hollow structure 2 is arranged on the insulating layer 15 located on one side of the cavity, the conductor layer 14 is exposed out of the hollow structure 2 to form a contact part, and the electric connection part 31 is connected with the contact part. Moreover, the housing 1 comprises a first half housing 11 and a second half housing 12 which are hermetically connected together, at least one of the first half housing 11 and the second half housing 12 comprises a concave structure and an edge part 13 which is formed by extending outwards from the edge of the concave structure; the hollow structure 2 is arranged on the concave structure.

According to the energy storage device provided by the embodiment of the invention, the electric connection part 31 on the energy conversion element 3 is not required to be led out from the edges of the first half shell 11 and the second half shell 12, so that the problem that the edge sealing and bending of the battery shell are difficult in the prior art is solved. This design also is convenient for form good sealing connection between first half casing 11 and second half casing 12, can improve whole casing 1's waterproof, dustproof performance, avoids causing harmful effects to inside energy conversion component 3. In the invention, through a special structural improvement, the housing 1 is designed to be a composite layer structure including the conductor layer 14 and the insulating layer 15, and the insulating layer 15 is provided with the hollow structure 2, so that the conductor layer 14 can be exposed in the hollow structure 2 to form a contact part, and thus, the electrical connection between the internal energy conversion element 3 and the outside can be realized through the conductor layer 14 exposed in the hollow structure 2. The energy storage device provided by the embodiment of the invention has a simpler structure, is more convenient to manufacture, and can meet good sealing requirements.

In the energy storage device provided by the embodiment of the present invention, a thermal isolation layer is further disposed between the energy conversion element 3 and the electrical connection portion 31. The heat insulating layer can play a role in insulating heat.

In an embodiment of the present invention, the exposed portion of the conductive layer 14 from the hollow structure 2, i.e. the contact portion, can be connected to the electrical connection portion 31 of the energy conversion element 3 by welding. The design of providing a thermal isolation layer between the energy conversion element 3 and the electrical connection portion 31 can effectively prevent heat generated during welding from being directly conducted to the energy conversion element 3, thereby causing damage to the energy conversion element 3. In the present embodiment, the energy storage device is, for example, a pouch battery, the energy conversion element 3 is, for example, a bare cell in the battery, and the electrical connection portion 31 is, for example, a tab or a region of the electrode sheet that is not covered with the electrode active material.

When the conductor layer 14 (contact portion) and the electrical connection portion 31 are welded, a solder joint or a weld bead penetrates the conductor layer 14 from the outside of the case 1. When welding, the welding pins are located outside the housing 1 instead of on the side of the recess structure. In this way, the housing 1 does not need to be left with a space for welding, for example, by laser welding. The beads or welds gradually diffuse inward from the outer surface of the conductor layer 14 to the electrical connection 31, where they melt and join together.

When the conductor layer 14 and the electrical connection portion 31 are welded, a solder joint or a weld bead may gradually spread from the contact surface between the conductor layer 14 and the electrical connection portion 31 to the surroundings. In this example, the welding pins are also located outside the housing 1. The soldering pins abut against the conductor layer 14. During welding, the current reaches the contact surface. Since there is a gap between the conductor layer 14 and the electrical connection portion 31 at the contact surface, a resistance can be formed. The contact surface gradually melts under the action of the current and causes the conductor layer 14 and the electrical connection 31 to be connected together.

Both of the above-described soldering methods can effectively connect the conductor layer 14 and the electrical connection portion 31.

In the invention, the welding of the electric connection part 31 on the energy conversion element 3 can adopt a steel shell battery welding technology, and the shell 1 of the battery can take account of the shell characteristics of the soft package battery, so that the battery is obviously improved in the aspects of safety and assembly process.

In another embodiment of the present invention, the conductive layer 14 of the housing 1 and the electrical connection portion 31 of the energy conversion element 3 may be in contact with each other by means of atmospheric pressure. By adopting the mode of atmospheric lamination, the conductive layer 14 can be pressed by atmospheric pressure without using a welding process, so that the conductive layer 14 and the electric connection part 31 can be tightly combined together, and the conductive layer 14 and the electric connection part 31 can realize good contact conduction.

In the energy storage device provided by the embodiment of the invention, as shown in fig. 1-3 and 5-7, the housing 1 includes a first housing half 11 and a second housing half 12, and the first housing half 11 and the second housing half 12 each have an open end. The first half-shell 11 and the second half-shell 12 may be, for example, snapped together in an open-end-to-end fashion and sealed together, with the first half-shell 11 and the second half-shell 12 together enclosing a receiving chamber. The energy conversion element 3 in the energy storage device is housed in the housing chamber. The first half shell 11 and the second half shell 12 can seal the energy conversion element 3 integrally to protect the energy conversion element 3, and can play a role in preventing water and dust.

Wherein, the energy conversion element 3 is for example a bare cell. Specifically, the energy conversion element 3 may be, but is not limited to, a bare lithium ion cell, a bare lithium metal cell, or the like, and may also be other types of bare cells known to those skilled in the art.

The housing 1 is, for example, a rectangular parallelepiped structure, a cylindrical structure, an elliptic cylindrical structure, or the like. The setting can be carried out by the person skilled in the art according to the actual need.

In the energy storage device provided by the embodiment of the invention, as shown in fig. 8, the housing 1 includes a conductor layer 14 and at least one insulating layer 15 which are compounded together. The conductor layer 14 may be made of a metal material such as an aluminum alloy material, a copper alloy material, or a stainless steel material. The insulating layer 15 is made of, for example, a plastic material. The person skilled in the art can flexibly adjust the device according to specific needs, without limitation. For example, the casing 1 is made of a metal plastic composite film.

The conductor layer 14 is typically a metal material, and can be used to improve the strength of the entire housing 1. Because the metal material surface is more compact, and the surface space is less, can play good dustproof, waterproof effect, can also effectively prevent the inside electrolyte of energy memory to ooze. Meanwhile, the conductor layer 14 has conductivity, and the electrical connection between the internal energy conversion element 3 and the outside can be realized through the conductor layer 14 without leading the electrical connection portion 31 of the energy conversion element 3 out of the case 1, which affects the sealing performance of the case 1 and causes difficulty in edge sealing and bending.

The insulating layer 15 is made of a non-conductive material, and when the insulating layer is used, an insulating film is provided between the electrical connection portion 31 of the energy conversion element 3 and the case 1, so that a short circuit phenomenon can be prevented.

In an embodiment of the invention, as shown in fig. 8, the conductor layer 14 includes an inner surface located at one side of the cavity, and an outer surface opposite to the inner surface, the insulating layers 15 are compounded on both the inner surface and the outer surface, and the hollow-out structures 2 are formed at corresponding positions of both the insulating layers 15. I.e. the conductor layer 14 is located in the middle, and insulating layers 15 are provided on both surfaces of the conductor layer 14, respectively. At this time, the hollow-out structures 2 are required to be formed on both the two insulating layers 15 to expose the conductive layer 14 to form a contact portion, so as to electrically connect the internal energy conversion element 3 with the outside through the contact portion. In this embodiment, the hollow structure 2 formed on the inner surface of the conductive layer 14 may be located right above the electrical connection portion 31 on the energy conversion element 3, for example, so as to facilitate contact and conduction with the electrical connection portion 31, and the specific position of the hollow structure 2 formed on the outer surface of the conductive layer 14 may be flexibly adjusted according to actual needs.

Optionally, the insulating layer 15 is compounded with the conductive layer 14 by injection molding or bonding, so that the conductive layer 14 and the insulating layer 15 can be well combined together.

Optionally, in the present invention, the hollow-out structure 2 is formed on the insulating layer 15 by a material removing process.

In a specific embodiment of the present invention, the housing 1 is made of a metal plastic composite film, the metal composite film is formed by punching, and then the plastic layer is subjected to a glue scraping treatment to form the hollow structure 2 at a suitable position.

In another embodiment of the present invention, the housing 1 is made of a metal plastic composite film, and a plastic layer of the metal plastic composite film may be subjected to a glue scraping process to form the hollow structure 2, and then the metal plastic composite film is subjected to a press forming process to form the housing 1.

In one embodiment of the invention, as shown in fig. 7 and 8, after the first half shell 11 and the second half shell 12 are hermetically connected, they are folded up and down, and the edge portion 13 is folded towards the side wall of the shell 1. The edge portion 13 is attached to the side wall of the housing 1. This design can be used to reduce the volume of the entire housing 1 to facilitate storage of the energy storage device. Meanwhile, the energy storage device is convenient to install in the electronic equipment, and occupied space during assembly can be reduced.

Wherein the edge portion 13 of the first half shell 11 is sealingly connected with the edge portion 13 of the second half shell 12 to form a sealing edge, a part of which is bent towards a first side of the shell and another part is bent towards a second side of the shell in a direction opposite to the first side.

For example, rather than being bent entirely to one side, a portion of the sealing edge is bent toward the first side and another portion is bent toward the second side. In this way, the resilience of the two lateral bends can be cancelled out, thus preventing the sealing edge from coming off the lateral wall of the housing 1.

Furthermore, the two-sided bending results in a larger circumferential distance of the sealing edge than the one-sided bending, and a part of the sealing edge is overlapping. In this way, the sealing edge can be uniformly applied to the outer surface of the housing 1 after bending without forming wrinkles. The surface of the energy storage device is flat.

In other examples, the sealing edge is a set distance from the outer surface of the housing 1 after bending, rather than abutting against the outer surface.

Alternatively, the edge portion 13 of the first half shell 11 and the edge portion 13 of the second half shell 12 may be welded together, for example, by heat fusion or ultrasonic welding.

The edge portions 13 of the two half shells are made of plastic. A color difference exists between the two edge portions 13. For example, the edge portion 13 of one of the half shells is made of transparent plastic, while the edge portion 13 of the other half shell is made of colored plastic, such as black plastic, green plastic or red plastic. When the design is adopted for laser welding, laser can penetrate from one side of the transparent plastic, and the plastic on the other side is opaque, so that the laser welding speed is higher.

In one embodiment of the present invention, bumps are disposed on the inner surface of the hollow structure 2 and/or the electrical connection portion 31 for contact. For example, a plurality of bumps are arranged on the inner surface of the hollow structure 2, and the plurality of bumps are distributed in a matrix. When evacuation is performed, the bumps first come into contact with the electrical connection portions 31. Due to the action of atmospheric pressure, a pit is formed in the electrical connection portion 31. The bumps and the pits are matched, so that the hollow structure 2 can be effectively prevented from moving relative to the electric connection part 31. This method is equivalent to directly contacting the hollow structure 2 with the electrical connection portion 31 of the energy conversion element 3, and the contact connection method is relatively simple. In addition, when the hollow structure 2 and the electrical connection part 31 are completely pressed, the contact area of the hollow structure 2 and the electrical connection part 31 can be increased by the salient points, and the hollow structure 2 and the electrical connection part 31 are in contact in space, not only in a plane. This makes the electrical connection of the two more stable.

The energy conversion element 3 of the present invention has a structure including: as shown in fig. 2, the energy conversion element body and the electrical connection portion 31 mechanically connected to the energy storage element body are included, or the electrical connection portion 31 is a portion of the energy storage element body extending from the surface thereof. In the present invention, the electrical connection portion 31 is electrically connected to the outside through the conductive layer 14, so that the electrical connection portion 31 does not need to be led out from the edges of the first half-shell 11 and the second half-shell 12, and the defects in the prior art are overcome.

The energy storage device provided by the invention can be a soft package battery, and can also be a steel shell battery. Energy conversion component 3 wherein is naked electric core, and it can be the naked electric core of coiling formula, also can the naked electric core of lamination formula, does not do the restriction to this. The wound bare cell, i.e., the whole sheet of electrode sheet (e.g., the electrode sheet includes a positive electrode sheet, a negative electrode sheet, and a separator between the positive electrode sheet and the negative electrode sheet) is wound into a spiral structure. Naked electric core of lamination formula is that the electrode slice is cut apart into a plurality of sheets, and a plurality of sheets are together laminated.

As shown in fig. 8, a stem 32 is further provided inside the energy conversion element 3, at least a part of the stem 32 is opposed to the electrical connection portion 31 (e.g., a tab), and the electrical connection portion 31 is compressed between the conductor layer 14 and the stem 32. The stem 32 is disposed at the middle position of the energy conversion element 3, so that the supporting force between the conductor layer 14 and the electrical connection portion 31 on the energy conversion element 3 can be further enhanced, better contact between the conductor layer and the electrical connection portion 31 can be realized, and the electrical connection portion 31 can be protected from being damaged by vertical pressure.

For example, the stem 32 is made of an insulating material, such as plastic, ceramic, or glass. The stem 32 is in the shape of a cylinder, square column, oval column, polygonal column, or the like.

For example, the energy conversion element 3 is wound around the stem 32. Electrical connection portions 31 are provided at both ends of the energy conversion element 3 in the axial direction. The two electrical connection portions 31 respectively abut against both ends of the stem 32. When vacuuming, the stem 32 can press the electrical connection portion 3 together with the conductor layer 14, so that the electrical connection portion 3 and the conductor layer 14 can be brought into good contact conduction.

While in other examples, the energy conversion element 3 is a laminated structure. The stems 32 are perpendicular to the surface of each layer. A core column 32 penetrating the layers is provided in the middle of the energy conversion element 3. The stem 32 also functions to support the electrical connection portion 31.

The energy storage device provided by the embodiment of the invention can be a soft package battery, a steel shell battery and the like. The energy storage device can be applied to various electronic equipment. For example, the electronic device may be, but is not limited to, a cell phone, a tablet, a smart watch, a laptop, a game console, an intercom, a headset, an e-book reader, and the like.

The electronic equipment comprises an electronic equipment shell and an energy storage device.

In one embodiment of the invention, a PCB is disposed within an electronic device housing. The energy storage device is arranged in the electronic shell and is electrically connected with the electric equipment in the electronic equipment through the PCB so as to supply power to the electric equipment, so that the electronic equipment can be normally used.

On the other hand, the embodiment of the invention also provides an assembling method of the energy storage device.

Wherein the energy storage device comprises an energy conversion element 3 and a housing 1. The energy conversion element 3 has at least one electrical connection 31 provided on its surface. The shell 1 comprises a conductor layer 14 and at least one insulating layer 15 which are compounded together, a cavity is formed inside the shell 1, the at least one insulating layer 15 is located on one side of the cavity, a hollow structure 2 is arranged on the insulating layer 15 located on one side of the cavity, and the conductor layer 14 is exposed out of the hollow structure 2 to form a contact part.

The assembling method of the energy storage device provided by the embodiment of the invention at least comprises the following steps:

the energy conversion element 3 is placed into the cavity.

Performing vacuum-pumping treatment on the inside of the shell 1, and pressing the contact part by using atmospheric pressure so as to make the contact part contact with the electric connection part 31 of the energy conversion element 3; and

the housing 1 is closed to form an energy storage device.

In the method for assembling the energy storage device according to the embodiment of the present invention, the cavity is evacuated, and the conductive layer 14 is pressed against the electrical connection portion 31 of the energy conversion element 3 by using atmospheric pressure. When the vacuum is pumped, the air pressure in the cavity is less than the atmospheric pressure. The local deformation of the housing 1 occurs under the effect of atmospheric pressure. The conductor layer 14 gradually approaches the electrical connection portion 31, eventually comes into contact with the electrical connection portion 31, and is closely attached together. During charging and discharging, the energy conversion element 3 is electrically connected to an external circuit through the electrical connection portion 31 and the conductor layer 14.

In the present embodiment, the conductor layer 14 is brought into contact with the electrical connection portion 31 of the energy conversion element 3 by atmospheric pressure by evacuating the cavity. Compared with the method of connecting the two by welding. In this way, the internal energy conversion element 3 is not affected by high temperatures, thereby maintaining good energy conversion performance.

In addition, when gas is present inside the cavity of the housing 1, for example, when the internal pressure is greater than the atmospheric pressure, the interior of the housing 1 gradually expands due to the internal pressure. The conductor layer 14 may gradually move away from the energy conversion element 3 until separated from the electrical connection portion 31. Thus, the conductive layer 14 and the electrical connection portion 31 are disconnected from each other, and the charging and discharging are stopped. Through the mode, the explosion of the energy storage device can be effectively avoided, and the use safety of the energy storage device is ensured.

Although some specific embodiments of the present invention have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustrative purposes only and are not intended to limit the scope of the present invention. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.

Claims

1. An energy storage device, characterized by: the method comprises the following steps:

2. The energy storage device of claim 1, wherein: the edge portions are welded together by means of hot melting or ultrasound.

3. The energy storage device of claim 1, wherein: and forming the hollow structure by a material removing treatment mode.

4. The energy storage device of claim 1, wherein: after the first half shell and the second half shell are hermetically connected, the two sides are folded up and down, and the edge part is folded towards the side wall of the shell.

5. The energy storage device of claim 1, wherein: the insulating layer is made of plastic.

6. The energy storage device of claim 1, wherein: the conductor layer comprises an inner surface and an outer surface, the inner surface is located on one side of the cavity, the outer surface is opposite to the inner surface, the insulating layers are compounded on the inner surface and the outer surface, and the hollow-out structures are formed in corresponding positions of the two insulating layers.

7. The energy storage device according to any one of claims 1 to 6, wherein: the energy conversion element comprises an energy conversion element body and the electric connection part mechanically connected with the energy storage element body, or the electric connection part is a part of the energy storage element body extending on the surface of the energy storage element body.

8. The energy storage device according to any one of claims 1 to 6, wherein: the energy conversion element is a winding type naked electric core or a laminated type naked electric core.

9. The energy storage device according to any one of claims 1 to 6, wherein: the electric connection part is welded with the inner surface of the contact part;

10. The energy storage device according to any one of claims 1 to 6, wherein: the energy storage device is a soft package battery.

11. A method of assembling an energy storage device, comprising: the energy storage device includes:

the assembling method comprises the following steps:

placing the energy conversion element into the cavity;

and closing the shell.

12. The method of assembling of claim 11, wherein: the electrical connection is separated from the contact when the air pressure within the cavity is above atmospheric pressure.