WO-2026091001-A1 - ELECTROCHEMICAL DEVICE AND PREPARATION METHOD THEREFOR, AND ELECTRONIC DEVICE

Abstract

An electrochemical device and a preparation method therefor, and an electronic device. The electrochemical device comprises a pouch, an electrode assembly and a conductive plate. The pouch comprises a main body portion and a sealing portion, and the electrode assembly is provided in the main body portion. The main body portion comprises a first end wall and a second end wall arranged opposite each other, and a first side wall and a second side wall arranged opposite each other. The sealing portion comprises a first sealing portion and a second sealing portion, wherein the first sealing portion is connected to the first end wall; the conductive plate extends out of the pouch from the first sealing portion; the second sealing portion is connected to the first side wall and disposed opposite the first side wall; the first sealing portion and the second sealing portion intersect within a connection region; the connection region is folded N times towards the first end wall to form a folded-corner structure; the folded-corner structure comprises N folded-corner portions; an N-th folded-corner portion is formed by folding the connection region for an N-th time towards the first end wall along an N-th folded-corner line; and the included angle between the N-th folded-corner line and the direction in which the conductive plate extends out of the pouch is α, where 15°≤α≤75°.

Inventors

• FANG, Dekai

Assignees

• 东莞新能源科技有限公司
• 宁德新能源科技有限公司

Dates

Publication Date

20260507

Application Date

20241031

Claims (20)

1. An electrochemical device includes a packaging bag, an electrode assembly, and a conductive plate. The packaging bag includes a main body and a sealing part. The electrode assembly is disposed within the main body, and the conductive plate is electrically connected to the electrode assembly. The conductive plate extends out of the packaging bag along a first direction, the thickness direction of the electrode assembly is a second direction, and the direction perpendicular to the first and second directions is a third direction. The main body includes a first end wall and a second end wall disposed opposite to each other in the first direction, and the main body also includes a first side wall and a second side wall disposed opposite to each other in the third direction; wherein... The sealing part includes a first sealing part and a second sealing part. The first sealing part is connected to the first end wall, and the conductive plate extends out of the packaging bag from the first sealing part. The second sealing part is connected to the first side wall, and the second sealing part and the first side wall are arranged opposite each other in the third direction. The first sealing part and the second sealing part intersect in the connecting area. The connecting area is folded N times toward the first end wall to form a folded structure, where N is an integer greater than or equal to 2. The folded structure includes N folded parts. The Nth folded part is formed by folding the connecting area along the Nth folded line toward the first end wall for the Nth time. The angle between the Nth folded line and the first direction is α, where 15°≤α≤75°.
2. The electrochemical device of claim 1, wherein the packaging bag includes a first encapsulation film and a second encapsulation film disposed opposite to each other in the second direction, the first encapsulation film including a first encapsulation layer, and the second encapsulation film including a second encapsulation layer; the first sealing portion includes a sealing region and a transition region, the transition region connecting the sealing region and the main body portion respectively in the first direction, the first encapsulation layer and the second encapsulation layer being bonded together in the sealing region, and the first encapsulation layer and the second encapsulation layer being separated in the transition region; The width of the sealing area in the first direction is 1.0 mm to 2.0 mm, and the width of the transition area in the first direction is 0.3 mm to 1.0 mm.
3. The electrochemical device of claim 2, wherein N = 2, the folded structure includes a first folded portion and a second folded portion, the first folded portion is formed by folding the connecting area along the first folded line toward the first end wall for the first time, and the second folded portion is formed by folding the connecting area along the second folded line toward the first end wall for the second time; when viewed from the second direction, the first folded portion and the second folded portion overlap.
4. The electrochemical device of claim 3, wherein the first bend line and the second bend line intersect at a first intersection point, and when viewed from the second direction, the first intersection point overlaps with the transition region.
5. The electrochemical device as described in claim 3, wherein 45°≤α≤75°, the first fold line and the second fold line intersect at a first intersection point, and when viewed from the second direction, the first intersection point overlaps with the sealing area.
6. The electrochemical device as described in any one of claims 3 to 5, wherein the first bend line comprises a first segment and a second segment connected together, the first segment being disposed on the first bend portion, and the second segment and the second bend... The corner line is set on the second corner portion.
7. The electrochemical device according to any one of claims 3 to 6, wherein, viewed from the third direction, the second sealing portion includes a first edge and a second edge disposed opposite to each other in the second direction, the second edge connecting to the first sidewall; the first segment intersects the first edge at a second intersection point, and viewed from the second direction, the first intersection point and the second intersection point do not coincide.
8. The electrochemical device of claim 6, wherein, when viewed from the second direction, the angle between the first segment and the first direction is β, where 0° < β ≤ 15°.
9. The electrochemical device of claim 5, wherein the first sealing portion includes a first region and a connecting region connected to each other, the first region connecting a portion of the first end wall, the connecting region including a first partition and a second partition connected to each other, the second partition connecting another portion of the first end wall and the first region respectively, the first sealing portion and the second sealing portion intersecting at the first partition; the first angle portion including a portion of the second partition.
10. The electrochemical device of claim 9, wherein the sealing region includes a third edge and a fourth edge disposed opposite to each other in the first direction; in the first region, the third edge is closer to the transition region than the fourth edge; and in the first direction, the distance between the first intersection point and the third edge in the first region is L, where L>0.3mm.
11. The electrochemical device according to any one of claims 3 to 10, wherein the electrochemical device further includes a first adhesive member, the first adhesive member being respectively bonded to the first bend portion and the second bend portion.
12. The electrochemical device of claim 2, wherein N = 3, the folding structure includes a first folding portion, a second folding portion, and a third folding portion, wherein the first folding portion is formed by folding the connecting area along the first folding line toward the first end wall for the first time, the second folding portion is formed by folding the connecting area along the second folding line toward the first end wall for the second time, and the third folding portion is formed by folding the connecting area along the third folding line toward the first end wall for the third time; when viewed from the second direction, the first folding portion, the second folding portion, and the third folding portion overlap in pairs.
13. The electrochemical device of claim 12, wherein the first bend line comprises a first segment and a second segment connected together, the first segment being disposed on the first bend portion; the second bend line comprises a third segment and a fourth segment connected together, the second segment and the third segment being disposed on the second bend portion, and the fourth segment and the third bend line being disposed on the third bend portion.
14. The electrochemical device as claimed in claim 12 or 13, wherein the third fold line intersects the second fold line at a third intersection point, and in the first direction, the distance between the third intersection point and the first end wall is greater than the distance between the first intersection point and the first end wall; and when viewed from the second direction, the third intersection point overlaps with the sealing area.
15. The electrochemical device of claim 12, wherein the first bend line comprises a first segment and a second segment connected together, the first segment comprises a first sub-segment and a second segment connected together, and the second sub-segment connects to the second... A bend line, wherein the first segment is disposed on the first bend portion, and the second segment, the second bend line, and the third bend line are disposed on the third bend portion.
16. The electrochemical device of claim 15, wherein the third fold line intersects the first segment at a third intersection point, and in the first direction, the third intersection point is located between the first intersection point and the first end wall; when viewed from the second direction, the third intersection point overlaps with the sealing area or the transition area.
17. The electrochemical device according to any one of claims 1 to 16, wherein the electrochemical device further includes a circuit board, the circuit board being electrically connected to the conductive plate; the first sealing portion and the first end wall together form an accommodating space, and the circuit board is disposed within the accommodating space.
18. An electronic device includes a battery compartment, wherein the electronic device further includes an electrochemical device as described in any one of claims 1 to 17, the electrochemical device being disposed within the battery compartment.
19. The electronic device of claim 18, wherein the battery compartment is at least partially arc-shaped.
20. A method for preparing an electrochemical device according to any one of claims 1 to 17, wherein the preparation method comprises the following steps: The electrode assembly is prepared and electrically connected to the conductive plate; The electrode assembly with the conductive plate is placed into the packaging bag and sealed to form the sealing part, and the conductive plate extends out of the packaging bag from the first sealing part; The sealing portion is folded so that it is positioned opposite the first sidewall in the third direction to form the second sealing portion; The connecting area is folded N times toward the first end wall to form the angled structure.

Description

Electrochemical devices and their preparation methods, electronic devices Technical Field This application relates to the field of energy storage technology, and in particular to an electrochemical device and its preparation method, as well as an electronic device having the electrochemical device. Background Technology Electrochemical devices (such as batteries) are widely used in electronic mobile devices, power tools, and electric vehicles. During the fabrication of electrochemical devices, the upper and lower encapsulation films are heat-sealed using a sealing head to form a seal, thereby encapsulating the electrode components within the housing. However, this sealing process can affect the energy density of the electrochemical device. Summary of the Invention Given the shortcomings of existing technologies, it is necessary to propose an electrochemical device that can improve energy density and its preparation method. Additionally, it is necessary to provide an electronic device having the electrochemical device. This application provides an electrochemical device, including a packaging bag, an electrode assembly, and a conductive plate. The packaging bag includes a main body and a sealing portion, with the electrode assembly disposed within the main body. The conductive plate is electrically connected to the electrode assembly. The conductive plate extends out of the packaging bag along a first direction, the thickness direction of the electrode assembly is a second direction, and a direction perpendicular to the first and second directions is a third direction. The main body includes a first end wall and a second end wall disposed opposite each other in the first direction, and also includes a first side wall and a second side wall disposed opposite each other in the third direction. The sealing portion includes a first sealing portion and a second sealing portion, the first sealing portion being connected to the first end wall, and the conductive plate extending out of the packaging bag from the first sealing portion. The second sealing portion is connected to the first side wall, and the second sealing portion and the first side wall are disposed opposite each other in the third direction. The first sealing portion and the second sealing portion intersect within a connection area. The connection area is folded N times toward the first end wall to form a folded structure, where N is an integer greater than or equal to 2. The folded structure includes N folded portions, the Nth folded portion being formed by folding the connection area along the Nth fold line toward the first end wall for the Nth time. The angle between the Nth bend line and the first direction is α, where 15°≤α≤75°. This application reduces the space occupied by the connecting area towards the first end wall by N folds, and sets an angle α between the fold line of the last fold and the first direction. This not only reduces the size of the first sealing part in the third direction and the size of the second sealing part in the first direction, thereby reducing the space occupied by the connecting area and increasing the energy density of the electrochemical device, but also allows the shape of the electrochemical device to better match the actual shape of the battery compartment of the electronic device, reducing the impact of a battery compartment with a specific shape on the energy density of the electrochemical device. Furthermore, by setting a lower limit value for the angle α, the energy density can be increased while making it easy to implement multiple folds, thereby improving production efficiency; by setting an upper limit value for the angle α, the energy density of the conductive plate on the Nth fold is reduced. The risk of bending during the second fold is reduced, which not only facilitates the electrical connection between the conductive plate and external components, but also reduces the risk of the electrochemical device failing due to the conductive plate breaking after bending. It also reduces the risk of electrochemical corrosion caused by the bent conductive plate puncturing the packaging bag and the electrolyte in the electrolyte coming into contact with the metal layer of the packaging bag, thus improving the reliability of the electrochemical device. Based on the first aspect, in some possible implementations, the packaging bag includes a first encapsulation film and a second encapsulation film disposed opposite each other in a second direction. The first encapsulation film includes a first encapsulation layer, and the second encapsulation film includes a second encapsulation layer. The first sealing portion includes a sealing region and a transition region, the transition region connecting the sealing region and the main body portion respectively in the first direction. The first encapsulation layer and the second encapsulation layer are bonded together in the sealing region, and the first encapsulation laye