WO2021217968A1 - Folding battery pack and vehicle - Google Patents

Abstract

Provided in the present disclosure are a folding battery pack and a vehicle. The folding battery pack comprises: a soft package battery cell laminated body, wherein the soft package battery cell laminated body comprises a plurality of layers of soft package battery cells, each layer of the soft package battery cell comprises a plurality of battery cell units, each battery cell unit has a positive piece, a positive tab, a negative piece, a negative tab, the battery cell units are connected in series, two adjacent layers of soft package battery cells have one bending portion, and the bending portion is formed by bending a connection portion of the two adjacent layers of soft package battery cell units; and a buffer foam provided between the two adjacent layers of soft package battery cells.

Description

Folding battery pack and vehicle

Priority information

This disclosure requests the priority of the Chinese patent application filed with the State Intellectual Property Office of China on April 30, 2020, with the patent application numbers 202010366224.X, 202020715584.1, and the application titled "Folding Battery Pack and Vehicle", and its entire contents Incorporated in this disclosure by reference.

Technical field

The present disclosure relates to the field of new energy vehicles. Specifically, the present disclosure relates to folding battery packs and vehicles.

Background technique

With the continuous popularization of new energy vehicles, the requirements for the use of power batteries in new energy vehicles have become higher and higher. In particular, users’ requirements for the continued mileage of new energy vehicles continue to increase. For common new energy vehicles, the power battery pack exceeds 1m in both the length and width directions; and currently on the market, the length of the battery module is generally around 0.3m. Therefore, at least three or even more battery modules need to be installed in the power battery pack.

To set up multiple battery modules, it is necessary to add a fixing structure to each battery module, and the assembly is complicated. At the same time, the power connection between two adjacent battery modules needs to be done through the power connector of the external device. There are many battery module installation structures, which not only increase the cost, but also increase the overall weight; at the same time, within the volume of a single module, the installation structure occupies more internal space, causing the power battery module and the overall capacity of the battery pack to decrease. The more battery modules are installed, the more space is wasted. In addition, because multiple external power connectors need to be provided for power connection, internal resistance and cost increase, and internal consumption and cost of the power battery pack in use are increased.

In summary, the existing battery packs for new energy vehicles still need to be improved.

Public content

The present disclosure aims to solve one of the technical problems in the related art at least to a certain extent. To this end, one object of the present disclosure is to propose a folding battery pack and a vehicle. The foldable battery pack is made by folding a plurality of series-connected soft-pack batteries, has fewer connection accessories, is convenient to assemble, and has better performance.

In one aspect of the present disclosure, the present disclosure proposes a folding battery pack. According to an embodiment of the present disclosure, the foldable battery pack includes: a soft-pack battery cell laminate, the soft-pack battery cell stack includes a multi-layer soft-pack battery cell, and each layer of the soft-pack battery cell includes a plurality of battery cells. The battery cell has a positive electrode sheet, a positive electrode lug, a negative electrode sheet, and a negative electrode lug, and each of the battery cells is connected in series; wherein two adjacent layers of the soft-covered battery core have a bending part , The bending part is formed by bending the connection parts of two adjacent battery cell monomers; buffer foam, the buffer foam is arranged between two adjacent layers of the soft-packed battery cells.

In the foldable battery pack according to the embodiment of the present disclosure, a plurality of battery cells are connected in series, and the connection part of the two battery cells is bent to form a soft-packed battery cell stack structure; by arranging buffer foam, It can not only provide a fixed pre-tightening force for the initial assembly of the battery pack, but also absorb the expansion force of the cell in the later stage of the battery pack. Therefore, the foldable battery pack has fewer connection accessories and is convenient to assemble, and can be directly assembled in series when the battery cells are offline. The foldable battery pack can reduce the series and parallel copper bars between the stacks and the external installation structure, reduce module group accessories, reduce cost and weight, improve space utilization, and can accommodate more pole groups in the battery pack. Improve the mileage of the vehicle. At the same time, the foldable battery pack reduces the use of external power connectors between modules, avoids bolt connections between modules, does not need to consider the connection stability and reliability of power connectors, reduces the internal resistance of the connection, and thus reduces the power battery The internal friction of the package in use.

In addition, the foldable battery pack according to the above-mentioned embodiments of the present disclosure may also have the following additional technical features:

In some embodiments of the present disclosure, the total thickness of the buffer foam is 5-20% of the total thickness of the soft-packed cell laminate.

In some embodiments of the present disclosure, a structural glue is provided between the buffer foam and the cell monomer in the soft-packed cell.

In some embodiments of the present disclosure, the thickness of the structural adhesive is 0.05 to 0.2 mm.

In some embodiments of the present disclosure, the strength of the structural adhesive is not less than 0.1 MPa.

In some embodiments of the present disclosure, each of the battery cells is connected in series by laser welding, ultrasonic welding or riveting.

In some embodiments of the present disclosure, the length of the folded battery pack is not less than 600 mm.

In some embodiments of the present disclosure, the foldable battery pack further includes: fixing plates, which are arranged on both sides of the foldable battery pack, and are respectively installed on the first layer of soft pack batteries and the last layer of soft packs On the outside of the battery core, the buffer foam is arranged between the fixed plate and the soft-packed battery core.

In some embodiments of the present disclosure, a plurality of fixing holes are distributed on the side surface.

In another aspect of the present disclosure, the present disclosure proposes a vehicle. According to an embodiment of the present disclosure, the vehicle includes the folding battery pack of the above-mentioned embodiment. Therefore, the vehicle has all the features and advantages described above for the folding battery pack, which will not be repeated here. In general, the vehicle has better reliability and cruising range.

The additional aspects and advantages of the present disclosure will be partly given in the following description, and part of them will become obvious from the following description, or be understood through the practice of the present disclosure.

Description of the drawings

The above and/or additional aspects and advantages of the present disclosure will become obvious and easy to understand from the description of the embodiments in conjunction with the following drawings, in which:

Fig. 1 is a schematic structural diagram of a folding battery pack according to an embodiment of the present disclosure;

Fig. 2 is a schematic structural diagram of a buffer foam in a folded battery pack according to an embodiment of the present disclosure;

3 is a schematic diagram of the structure of a battery cell in a folding battery pack according to an embodiment of the present disclosure;

4 is a schematic structural diagram of a plurality of battery cells connected in series in a folded battery pack according to an embodiment of the present disclosure;

FIG. 5 is a schematic structural diagram of a plurality of battery cells connected in series in a folded battery pack according to an embodiment of the present disclosure;

Figure 6 is a cross-sectional view of the A-A plane in Figure 5;

FIG. 7 is a schematic structural diagram of a plurality of battery cells connected in series and a folding tooling in a folding battery pack according to an embodiment of the present disclosure;

FIG. 8 is a schematic structural diagram of a folding battery pack according to an embodiment of the present disclosure;

Fig. 9 is a schematic structural diagram of a fixing plate in a foldable battery pack according to an embodiment of the present disclosure.

Detailed ways

The embodiments of the present disclosure are described in detail below. Examples of the embodiments are shown in the accompanying drawings, in which the same or similar reference numerals denote the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the drawings are exemplary, and are intended to explain the present disclosure, but should not be construed as limiting the present disclosure.

In the description of the present disclosure, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", " The orientation or positional relationship indicated by “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, and “outer” are based on the orientation shown in the drawings The or positional relationship is only for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present disclosure.

In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present disclosure, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

In the present disclosure, unless otherwise clearly defined and defined, terms such as "installation", "connected", "connected", and "fixed" shall be understood in a broad sense. For example, it may be a fixed connection or a detachable connection. Or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, it can be the internal communication of two components or the interaction relationship between two components, unless otherwise clear limited. For those of ordinary skill in the art, the specific meaning of the above-mentioned terms in the present disclosure can be understood according to specific circumstances.

In the present disclosure, unless otherwise clearly defined and defined, the first feature “on” or “under” the second feature may be in direct contact with the first and second features, or the first and second features may be indirectly through an intermediary. touch. Moreover, the "above", "above" and "above" of the first feature on the second feature may mean that the first feature is directly above or diagonally above the second feature, or it simply means that the level of the first feature is higher than the second feature. The “below”, “below” and “below” of the second feature of the first feature may be that the first feature is directly below or obliquely below the second feature, or it simply means that the level of the first feature is smaller than the second feature.

In one aspect of the present disclosure, the present disclosure proposes a folding battery pack. 1 to 5, according to an embodiment of the present disclosure, the foldable battery pack includes: a soft-packed battery cell stack, the soft-packed battery cell stack includes multiple layers of soft-packed batteries, and each layer of soft-packed batteries includes multiple Each battery cell 100 has a positive electrode sheet, a positive electrode lug 110, a negative electrode sheet and a negative electrode lug 120, and each battery cell 100 is connected in series; wherein, two adjacent layers of soft-packed batteries have a curved The bending part 200 is formed by bending the connecting part of two adjacent battery cells 100. Buffer foam, the buffer foam is arranged between two adjacent layers of soft-packed batteries.

In the foldable battery pack according to the embodiment of the present disclosure, a plurality of battery cells are connected in series, and the connection part of the two battery cells is bent to form a soft-packed battery cell stack structure; by arranging buffer foam, It can not only provide a fixed pre-tightening force for the initial assembly of the battery pack, but also absorb the expansion force of the cell in the later stage of the battery pack. Therefore, the foldable battery pack has fewer connection accessories and is convenient to assemble, and can be directly assembled in series when the battery cells are offline. The foldable battery pack can reduce the series and parallel copper bars between the stacks and the external installation structure, reduce module group accessories, reduce cost and weight, improve space utilization, and can accommodate more pole groups in the battery pack. Improve the mileage of the vehicle. At the same time, the foldable battery pack reduces the use of external power connectors between modules, avoids bolt connections between modules, does not need to consider the connection stability and reliability of power connectors, reduces the internal resistance of the connection, and thus reduces the power battery The internal friction of the package in use.

Hereinafter, the foldable battery pack according to the embodiment of the present disclosure will be further described in detail with reference to FIGS. 1-9.

Fig. 1 shows a schematic structural diagram of a folding battery pack according to an embodiment of the present disclosure. In the foldable battery pack, each layer of soft-packed battery cells includes three battery cells 100. In each layer of soft-packed battery cells, the positive electrode ears and the negative electrode ears of two adjacent battery cell units 100 are connected, thereby connecting each battery cell unit 100 in series. Fig. 2 shows a schematic structural diagram of a buffer foam in a folded battery pack according to an embodiment of the present disclosure. The buffer foam is arranged between two adjacent layers of soft battery cells. In addition, it should be noted that FIG. 1 does not show the buffer foam provided between the two layers of soft-packed batteries.

According to some embodiments of the present disclosure, the total thickness of the above-mentioned buffer foam may be 5-20% of the total thickness of the soft-packed cell laminate. Therefore, suitable buffering can be provided for the battery pack without excessively increasing the volume of the battery pack.

According to some embodiments of the present disclosure, a structural glue is provided between the buffer foam and the cell monomer in the soft-packed cell. As a result, the structural stability between two adjacent layers of soft-covered cells can be further improved. In addition, the two adjacent layers of soft-packed cells are bonded by structural glue, which will not cause excessive influence on the volume of the battery pack.

According to some embodiments of the present disclosure, the thickness of the aforementioned structural adhesive may be 0.05 to 0.2 mm, for example, 0.05 mm, 0.1 mm, 0.15 mm, 0.2 mm, and so on. As a result, the structural stability between two adjacent layers of soft-covered cells can be further improved.

According to some embodiments of the present disclosure, the strength of the aforementioned structural adhesive is not less than 0.1 MPa, for example, it may be 0.1 MPa, 0.2 MPa, 0.5 MPa, 1 MPa, 2 MPa, and the like.

In the foldable battery pack of the present disclosure, the battery cell can be a soft-packed battery cell commonly used in the art. Referring to FIG. 3, the battery cell 100 includes a positive electrode sheet, a positive electrode lug 110, a negative electrode sheet, and a negative electrode lug 120. The battery cell is also wrapped with a packaging structure, such as aluminum plastic film.

The structural schematic diagrams of a plurality of battery cells 100 connected in series that are not folded are shown in Figs. 4-6. As shown in Figs. 4-6, the positive ears and the negative ears of two adjacent battery cells 100 are connected to achieve series connection. Further, according to actual needs, the junction of the positive electrode ear and the negative electrode ear of two adjacent battery cells can be bent to complete the stacking. Specifically, referring to FIG. 7, the bending operation can be completed by the upper tool 310 and the lower tool 320.

According to some embodiments of the present disclosure, the individual battery cells are connected in series by laser welding, ultrasonic welding or riveting. The positive and negative electrode tabs of the two battery cells are connected by the above-mentioned connection method, and the joint part obtained by the connection is easy to bend.

According to some embodiments of the present disclosure, the length of the folded battery pack of the present disclosure is not less than 600 mm. The folding battery pack of the present disclosure is formed by connecting and folding a plurality of battery cells, and the specific folding position is selected according to actual needs, so that the length of the folding battery pack can be easily adjusted. By designing the length of the folding battery pack to be no less than 600mm, it can meet the adaptation requirements of common new energy vehicle battery packs.

Referring to FIG. 8, according to some embodiments of the present disclosure, the folding battery pack of the present disclosure may further include: a fixing plate 400. The fixing plate 400 is arranged on both sides of the folded battery pack, and is respectively installed on the outer side of the first layer of soft-packed batteries and the last layer of soft-packed batteries, and buffer foam is arranged between the fixing plate 400 and the soft-packed batteries. Specifically, the fixing plate 400 may be bonded to the buffer foam by using structural glue, and at the same time, the buffer foam and the inner soft-packed battery cell are also bonded by structural glue. As a result, the fixing plate can be used to fix the multilayer soft-packed battery cell, which further improves the structural stability of the multilayer soft-packed battery core.

Referring to FIG. 9, according to some embodiments of the present disclosure, a plurality of fixing holes 410 are distributed on the side of the fixing plate 400. The fixing hole 410 can be used to install and fix the foldable battery pack in the battery system.

In summary, the folding battery pack according to the embodiments of the present disclosure has at least one of the following advantages:

1. The internal connection of the foldable battery pack has no additional conductive structures such as copper bars or aluminum bars, which has low cost and fast connection;

2. The batteries in the folding battery pack can be welded directly with the assembly line after the battery production workshop is off the assembly line. After welding, bend at different positions of the batteries according to the system requirements to achieve stacking and high assembly efficiency;

3. Direct connection between the tabs, reducing connection accessories, reducing costs, and increasing connection reliability;

4. Compared with the traditional battery module in which each module requires four bolts to fix and connect, the number of fixing bolts and the number of fixing bolts for each module is reduced, and the production efficiency is greatly improved;

5. Compared with the traditional battery module that requires four bolts to fix, the folding battery pack with the same number of cells does not need to reserve space for installation, module expansion, and external connection, which can greatly improve the folding battery in the battery pack. Volume utilization in the system.

In another aspect of the present disclosure, the present disclosure proposes a vehicle. According to an embodiment of the present disclosure, the vehicle includes the folding battery pack of the above-mentioned embodiment. Therefore, the vehicle has all the features and advantages described above for the folding battery pack, which will not be repeated here. In general, the vehicle has better reliability and cruising range.

In the description of this specification, descriptions with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean specific features described in conjunction with the embodiment or example , Structures, materials, or characteristics are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine the different embodiments or examples and the features of the different embodiments or examples described in this specification without contradicting each other.

Although the embodiments of the present disclosure have been shown and described above, it can be understood that the above-mentioned embodiments are exemplary and should not be construed as limiting the present disclosure. Those of ordinary skill in the art can comment on the foregoing within the scope of the present disclosure. The embodiment undergoes changes, modifications, substitutions, and modifications.

Claims (10)

1. A folding battery pack, which includes:

   A soft-pack battery cell stack, the soft-pack battery cell stack includes a multi-layer soft-pack battery core, each layer of the soft-pack battery cell includes a plurality of battery cell monomers, and the battery cell monomer has a positive electrode sheet and a positive electrode. The ears, the negative electrode sheet, and the negative electrode ear are connected in series between each of the battery cells; wherein the two adjacent layers of the soft-packed battery cores have a bending part, and the bending part is formed by two adjacent ones. The connection part of the battery cell is bent;

   Buffer foam, the buffer foam is arranged between two adjacent layers of the soft-packed battery cores.
2. The foldable battery pack according to claim 1, wherein the total thickness of the buffer foam is 5-20% of the total thickness of the soft-packed cell laminate.
3. The foldable battery pack according to claim 1 or 2, wherein a structural glue is provided between the buffer foam and the battery cell in the soft-packed battery cell.
4. The foldable battery pack according to any one of claims 1 to 3, wherein the thickness of the structural adhesive is 0.05 to 0.2 mm.
5. The foldable battery pack according to any one of claims 1 to 4, wherein the strength of the structural glue is not less than 0.1 MPa.
6. The foldable battery pack according to any one of claims 1 to 5, wherein each of the battery cells are connected in series by laser welding, ultrasonic welding or riveting.
7. The folded battery pack according to any one of claims 1 to 6, wherein the length of the folded battery pack is not less than 600 mm.
8. The foldable battery pack according to any one of claims 1 to 7, further comprising:

   The fixing plate is arranged on both sides of the folding battery pack and is respectively installed on the outer side of the first layer of soft-packed batteries and the last layer of soft-packed batteries, between the fixing plate and the soft-packed batteries The buffer foam is provided.
9. The foldable battery pack according to claim 8, wherein a plurality of fixing holes are distributed on the side surface.
10. A vehicle comprising: the foldable battery pack according to any one of claims 1-9.

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