CN210073924U

CN210073924U - Battery packaging film and soft package battery

Info

Publication number: CN210073924U
Application number: CN201921327104.8U
Authority: CN
Inventors: 邹十美; 钟宽; 李影; 谷建行; 魏文飞; 吴西燚; 孔雪
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2019-08-15
Filing date: 2019-08-15
Publication date: 2020-02-14
Anticipated expiration: 2029-08-15

Abstract

The utility model relates to a battery packaging film and laminate polymer battery, battery packaging film are including at least one deck function rete and at least one deck buffer layer of range upon range of setting, and the buffer layer is used for absorbing the mechanical force. Above-mentioned battery packaging film, when laminate polymer battery received external impact force, the buffer layer can play the cushioning effect and avoid electric core to receive the injury in order to protect, also can effectively improve laminate polymer battery's anti extrusion performance simultaneously, reduces laminate polymer battery and falls or vibrate the probability of back damage.

Description

Battery packaging film and soft package battery

Technical Field

The utility model relates to a battery technology field especially relates to a battery packaging film and laminate polymer battery.

Background

Lithium batteries are widely used in various devices due to their high energy density, high operating voltage, no memory effect, long cycle life, and the like. The soft package battery serving as one type of lithium battery has the characteristics of light weight, high safety, high energy density, small internal resistance and the like, so that the soft package battery is widely applied to various devices.

The soft package battery usually adopts the plastic-aluminum complex film as external packaging material with the encapsulation electric core, but soft package battery takes place the phenomenon of burning on fire very easily when receiving external force and assaulting. Particularly, at present, the thickness of the soft package battery is thinner and thinner along with the improvement of the cell energy density, so that the impact resistance is weaker and weaker. Therefore, how to improve the impact resistance of the soft package battery becomes a problem to be solved urgently in the field.

SUMMERY OF THE UTILITY MODEL

In view of this, it is necessary to provide a battery packaging film and a pouch battery in order to solve the problem that the pouch battery is weak in impact resistance.

A battery packaging film comprises at least one functional film layer and at least one buffer layer which are arranged in a stacked mode, wherein the buffer layer is used for absorbing mechanical force.

Above-mentioned battery packaging film, when laminate polymer battery received external impact force, the buffer layer can play the cushioning effect and avoid electric core to receive the injury in order to protect, also can effectively improve laminate polymer battery's anti extrusion performance simultaneously, reduces laminate polymer battery and falls or vibrate the probability of back damage.

In one embodiment, each of the buffer layers can be reversibly deformed by a mechanical force to absorb the mechanical force.

In one embodiment, each of the buffer layers includes a plurality of buffer units for absorbing mechanical force, and the plurality of buffer units are arranged along a plane parallel to the functional film layer.

In one embodiment, a plurality of the buffer units are arranged in an array, and adjacent buffer units are connected with each other.

In one embodiment, each buffer unit comprises a buffer shell and a buffer medium filled in the buffer shell.

In one embodiment, the buffer medium is in a gas state, a liquid state, a gas-liquid mixed state or a solid-liquid mixed state.

In one embodiment, the buffer layer is formed of a material that does not undergo a side reaction with the electrolyte.

In one embodiment, the battery packaging film comprises three functional film layers which are stacked, the three functional film layers are respectively a protective layer, a waterproof layer and an encapsulation layer, and at least one buffer layer is arranged at least one of the positions between the protective layer and the waterproof layer, between the waterproof layer and the encapsulation layer and on one side of the encapsulation layer far away from the waterproof layer.

In one embodiment, the functional film layer has a main accommodating area and a sealing area surrounding the periphery of the main accommodating area, and the buffer layer is located in the main accommodating area.

The utility model provides a laminate polymer battery which characterized in that, includes foretell battery packaging film, laminate polymer battery includes electric core, battery packaging film cladding in outside the electric core.

In one embodiment, the thickness of the buffer layer of the battery packaging film is 0.1% -5% of the thickness of a soft package battery.

Drawings

Fig. 1 is a schematic structural diagram of a pouch battery according to an embodiment of the present invention;

fig. 2 is a cross-sectional view of a battery packaging film according to an embodiment of the present invention;

fig. 3 is a cross-sectional view of a battery packaging film according to another embodiment of the present invention;

fig. 4 is a cross-sectional view of a battery packaging film according to yet another embodiment of the present invention;

fig. 5 is a cross-sectional view of a battery packaging film according to yet another embodiment of the present invention;

fig. 6 is a cross-sectional view of a battery packaging film according to yet another embodiment of the present invention;

fig. 7 is a sectional view of a battery packaging film according to yet another embodiment of the present invention;

fig. 8 is a sectional view of a battery packaging film according to yet another embodiment of the present invention;

fig. 9 is a sectional view of a battery packaging film according to still another embodiment of the present invention.

Detailed Description

In order to facilitate understanding of the present invention, the present invention will be described more fully hereinafter with reference to the accompanying drawings. The preferred embodiments of the present invention are shown in the drawings. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

As shown in fig. 1, in the embodiment of the present invention, the pouch battery 100 includes a battery cell 40 and a battery packaging film 20 coated outside the battery cell 40 to encapsulate the battery cell 40.

As shown in fig. 2, the battery packaging film 20 includes at least one functional film layer and at least one buffer layer 27, which are stacked, the functional film layer is used to form a main structure of the battery packaging film 20, and the buffer layer 27 can be restored to deform under the action of a mechanical force to absorb the mechanical force.

So, when laminate polymer battery 100 received external impact force, buffer layer 27 can play the cushioning effect and avoid electric core 40 to receive the injury in order to protect, also can effectively improve laminate polymer battery 100's anti extrusion performance simultaneously, reduces laminate polymer battery 100 and falls or vibrates the probability of back damage.

Specifically, the battery packaging film 20 includes three functional film layers stacked together, which are a protective layer 21, a waterproof layer 23, and an encapsulation layer 25. When the battery packaging film 20 covers the battery core 40, the packaging layer 25 is located on the side of the battery packaging film 20 facing the battery core 40, and the protective layer 21 is located on the outermost side of the battery packaging film 20.

The protective layer 21 is made of a material such as nylon, and is used to keep the outer shape of the battery packaging film 20 from being deformed. The waterproof layer 23 is made of metal aluminum, and the metal aluminum reacts with oxygen in the air at room temperature to form a dense oxide film, so that moisture can be prevented from permeating into the battery cell 40. The packaging layer 25 is formed by polypropylene, polyethylene, polyvinylidene fluoride and other materials which do not generate side reaction with the electrolyte, and the packaging layer 25 can be melted and bonded at the high temperature of the end socket, so that the battery cell 40 is packaged. It can be understood that the number of layers of the functional film layer is not limited, and the materials of different functional film layers can be set according to the requirement.

As shown in fig. 2-4, in some embodiments, the battery packaging film 20 includes a buffer layer 27, and the buffer layer 27 may be located between the protective layer 21 and the waterproof layer 23 (as shown in fig. 2), between the waterproof layer 23 and the encapsulation layer 25 (as shown in fig. 3), or on the side of the encapsulation layer 25 away from the waterproof layer 23 (as shown in fig. 4). Thus, the buffer layer 27 can be located on one side of different functional films as required, and the buffer layers 27 located at different positions can play the same buffering and protecting functions. When the battery cell 40 covered with the battery packaging film 20 swells, the buffer layer 27 can buffer the pressure from the battery cell 40 and maintain the external shape of the pouch battery 100.

As shown in fig. 5-7, in some embodiments, the battery packaging film 20 includes a plurality of buffer layers 27 stacked in sequence, and the plurality of buffer layers 27 may be located between the protective layer 21 and the waterproof layer 23 (as shown in fig. 5), between the waterproof layer 23 and the encapsulation layer 25 (as shown in fig. 6), or on a side of the encapsulation layer 25 away from the waterproof layer 23 (as shown in fig. 7). The multi-layer buffer layer 27 may provide a better buffering effect than the single-layer buffer layer 27.

In other embodiments, as shown in fig. 8 and 9, the battery packaging film 20 includes a plurality of buffer layers 27 separately disposed, and each buffer layer 27 is disposed on one side of a different functional film layer, or on one side of a certain functional film layer. As shown in fig. 8, in one embodiment, the battery packaging film 20 includes three buffer layers 27, wherein one buffer layer 27 is disposed between the protection layer 21 and the waterproof layer 23, one buffer layer 27 is disposed between the waterproof layer 23 and the encapsulation layer 25, and one buffer layer 27 is disposed on a side of the encapsulation layer 25 away from the waterproof layer 23. In another embodiment, as shown in fig. 9, the battery packaging film 20 includes two buffer layers 27, and the two buffer layers 27 are respectively disposed between the protective layer 21 and the waterproof layer 23, between the waterproof layer 23 and the encapsulation layer 25, and/or at two positions on a side of the encapsulation layer 25 away from the waterproof layer 23. Thus, the multi-layer buffer layer 27 forms multi-level buffering, and further improves the buffering performance of the soft package battery 100.

It is understood that the number and stacking manner of the buffer layers 27 are not limited to the above, and different arrangement manners may be provided as needed to meet different buffer requirements.

Referring back to fig. 2, each of the buffer layers 27 includes a plurality of buffer units 272 for absorbing mechanical force, the plurality of buffer units 272 are arranged in a planar array parallel to the functional film, and the adjacent buffer units 272 are connected to each other. The shape of each buffer unit 272 may be regular or irregular, such as a sphere, an ellipsoid, a column, etc., as required.

In this manner, the plurality of buffer units 272, which are independent of each other, are connected to each other to form a buffer layer 27, thereby providing the buffer layer 27 with higher structural stability. It is to be understood that the number of the buffer units 272 in each layer of the buffer layer 27 is not limited, and in some embodiments, there may be only one buffer unit 272 in each layer of the buffer units 272.

Further, the buffer unit 272 includes a buffer housing and a buffer medium filled in the buffer housing, and the buffer medium is in a gas state, a liquid state, or a gas-liquid mixed state, so that the buffer medium can be restored to deform under the action of an external impact force to absorb the action of the impact force. Specifically, the buffer medium may be air, nitrogen, argon, or other gas that does not react with the electrolyte, or may be formed of a material that does not react with the electrolyte and is in a liquid state, a gas-liquid mixed state, a solid-liquid mixed state, or other state. It will be appreciated that in some embodiments, buffer layer 27 is a unitary solid structure formed from a solid material that is elastically deformable by an external force.

In some embodiments, the outer diameter of each buffer unit 272 is 1-20mm, and the thickness of all buffer layers 27 is 0.1% -5% of the total thickness of the pouch battery 100. In this way, the buffer layer 27 can play a certain buffering role and simultaneously can not cause the thickness of the soft package battery 100 to be too thick. It is understood that the size of the buffer unit 272 and the thickness of the buffer layer 27 are not limited, and may be set according to different requirements.

In some embodiments, the battery packaging film 20 has a main receiving area for receiving the battery cell 40 and a sealing area surrounding the outer periphery of the main receiving area, and the sealing area can be sealed under heat and pressure of the sealing head. The buffer layer 27 is located only within the primary containment area to facilitate encapsulation of the cells 40. Specifically, in some embodiments, the edge of the cushioning layer 27 coincides with the edge of the main containment area.

Above-mentioned battery packaging film 20 and laminate polymer battery 100 absorb the outside effort that laminate polymer battery 100 received through buffer layer 27, have effectively improved laminate polymer battery 100's shock resistance, anti extrusion performance, have increased laminate polymer battery 100 and have received the security performance when falling, shaking. Moreover, the buffer layer 27 can also buffer the pressure from the inside of the battery cell 40, and stabilize the complete shape of the soft package battery 100.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A battery packaging film, characterized in that it comprises at least one functional film layer and at least one buffer layer (27) arranged in a stack, said buffer layer (27) being adapted to absorb mechanical forces.

2. The battery packaging film of claim 1, wherein each of the buffer layers (27) is reversibly deformable under mechanical force to absorb mechanical force.

3. The battery packaging film according to claim 1, wherein each of the buffer layers (27) comprises a plurality of buffer units (272) for absorbing mechanical force, the plurality of buffer units (272) being arranged along a plane parallel to the functional film layer.

4. The battery packaging film according to claim 3, wherein a plurality of the buffer units (272) are arranged in an array, and adjacent buffer units (272) are connected to each other.

5. The battery packaging film according to claim 3, wherein each of the buffer units (272) comprises a buffer housing and a buffer medium filled in the buffer housing.

6. The battery packaging film according to claim 5, wherein the buffer medium is in a gaseous state, a liquid state, a gas-liquid mixed state, or a solid-liquid mixed state.

7. The battery packaging film according to claim 1, wherein the buffer layer (27) is formed of a material that does not undergo a side reaction with an electrolyte.

8. The battery packaging film according to claim 1, wherein the battery packaging film comprises three functional film layers which are stacked, each functional film layer comprises a protective layer (21), a waterproof layer (23) and an encapsulation layer (25), and at least one buffer layer (27) is arranged at least one of the positions between the protective layer (21) and the waterproof layer (23), between the waterproof layer (23) and the encapsulation layer (25) and on the side of the encapsulation layer (25) far away from the waterproof layer (23).

9. The battery packaging film of claim 1, wherein the functional film layer has a main receiving area and a seal area surrounding the outer periphery of the main receiving area, and the buffer layer (27) is located in the main receiving area.

10. A pouch battery, characterized by comprising the battery packaging film according to any one of claims 1-9, wherein the pouch battery comprises a battery cell (40), and the battery packaging film is coated outside the battery cell (40).

11. The pouch cell according to claim 10, wherein the buffer layer (27) of the cell packaging film has a thickness of 0.1-5% of the thickness of the pouch cell.