阅读说明：本技术 一种可折叠的电池及其制备方法 (Foldable battery and preparation method thereof ) 是由 黄涛 于 2018-08-03 设计创作，主要内容包括：本发明公开了一种可折叠电池及其制备方法,涉及锂电池领域,所述电池包括n块电池内芯,[(n-1)×2]个连接件,电解液和外壳,其中相邻两个电池内芯通过2个所述连接件连接,所述连接件将相邻两个电池内芯的正极集流体、负极集流体分别连接,其中,n≥2,且为整数。连接相邻两个电池内芯之间的连接件形成可弯折的节点,通过连接件,使电池内芯之间可以弯折、折叠,增加电池的可针对性和柔顺性,达到增加电池内芯的厚度,显著增大电池整体容量目的。本发明的电池可广泛地应用于可折叠手机、可折叠平板设备、智能手表和其他可弯曲数码设备。(The invention discloses a foldable battery and a preparation method thereof, and relates to the field of lithium batteries, wherein the battery comprises n battery cores, [ (n-1). times.2 ] connecting pieces, electrolyte and a shell, wherein two adjacent battery cores are connected through 2 connecting pieces, the connecting pieces are used for respectively connecting a positive current collector and a negative current collector of the two adjacent battery cores, wherein n is more than or equal to 2 and is an integer. The connecting pieces between the two adjacent battery inner cores are connected to form bendable nodes, so that the battery inner cores can be bent and folded through the connecting pieces, pertinence and flexibility of the battery are improved, the thickness of the battery inner cores is increased, and the purpose of obviously increasing the whole capacity of the battery is achieved. The battery of the invention can be widely applied to foldable mobile phones, foldable tablet devices, smart watches and other bendable digital devices.)

1. A foldable battery comprises n battery cores, [ (n-1) x 2] connecting pieces, electrolyte and a shell, wherein two adjacent battery cores are connected through 2 connecting pieces, the connecting pieces are used for respectively connecting a positive current collector and a negative current collector of the two adjacent battery cores, n is not less than 2 and is an integer; the connecting piece for connecting two adjacent battery cores can be bent and folded.

2. The foldable battery of claim 1, the connector being made of a flexible conductive metal.

3. The foldable battery of claim 2, the flexible conductive metal selected from one or more of aluminum, copper, nickel, gold, or platinum.

4. The foldable battery of claim 1, the connectors being parallel to and spaced apart from each other.

5. The foldable battery of claim 1, wherein the battery core is a cube made of positive electrode current collector, positive electrode material, separator, negative electrode material, and negative electrode current collector by winding, stacking, or other methods.

6. A method of making a foldable battery, comprising the steps of:

step 1, preparing a battery inner core

Preparing n battery cores by adopting a winding method, a stacking method or other methods, wherein the battery cores are cubes made of a positive current collector, a positive material, a diaphragm, a negative material and a negative current collector, and n is an integer and is more than or equal to 2;

step 2, fixed connection processing

Connecting the battery inner cores with each other through a flexible conductive metal connecting piece, wherein the positive current collectors of two adjacent battery inner cores are connected with each other through a flexible conductive metal connecting piece; the negative current collectors are connected with each other through another flexible conductive metal connecting piece;

step 3, packaging treatment

Placing the connected battery inner core into a battery shell/outer membrane; then injecting electrolyte; the battery housing/outer membrane is sealed to form a foldable battery.

7. The method according to claim 6, wherein the flexible conductive metal in step 2 is selected from one or more of aluminum, copper, nickel, gold or platinum.

8. The method according to claim 6, wherein the electrolyte in step 3 is selected from a lithium ion electrolyte or a lithium polymer electrolyte.

9. The method for preparing a battery pack according to claim 6, wherein the battery case/outer film in step 3 is an aluminum plastic film, a polyethylene film or a polypropylene film.

Technical Field

The invention relates to the technical field of lithium batteries, in particular to a foldable battery and a preparation method thereof.

Background

The lithium ion battery consists of an inner core, electrolyte and an outer package, wherein the inner core consists of a positive current collector, a negative current collector, a positive material, a negative material and a diaphragm. The electric core of the common lithium ion battery (including the lithium polymer battery) is formed by overlapping a plurality of layers of positive and negative electrodes, and when the number of the layers reaches a certain value, the flexibility and the folding cannot be realized.

Foldable devices are being studied more and more deeply by various manufacturers, wherein models of foldable flat panels, foldable mobile phones and the like are already available. Folding equipment requires that all major components be foldable, such as: display, motherboard, battery, etc. Softening; the technology of the display has been broken through, the folding of the main board can be realized by connecting two or more main boards by using a flat cable hidden at the folding position, but the foldable battery has not been researched in a breaking way. The current folding battery scheme is realized by using flexible materials and changing the anode and the cathode of the battery into flexible materials, and has the defects that the batteries have smaller electric capacity and cannot be made thick.

The popularization of wearable equipment, such as intelligent wrist-watch, if can put into the watchband with collapsible battery, can prolong intelligent wrist-watch operating time greatly. Other wearable equipment can also make the collapsible battery certain shape, puts into the casing of arbitrary shape.

Current collapsible/flexible battery research has focused on making the inner core flexible, making it a flexible battery. The flexible battery technology requires that the positive current collector, the negative current collector, the positive and negative electrode materials and the battery shell material of the battery are all flexible. The flexible battery is low in capacity, thin in thickness and high in industrialization difficulty at present.

For example, the invention patent "a foldable lithium ion battery and a manufacturing method thereof" with the publication number of CN104681857B discloses a foldable lithium ion battery, which can be folded, and the inner core of the battery is flexible and does not contain flexible nodes, but the battery of the solution can not be made very thick, so the battery capacity is relatively low.

Another example is: the invention patent application publication No. CN102024926 discloses a "foldable battery cartridge and medium or large-sized battery module", the battery having two or more batteries mounted therein, wherein the battery cartridge comprises a rotation part formed in a cartridge case having a substantially flat plate shape in the longitudinal direction of the battery cartridge and/or in the transverse direction of the battery cartridge, so that the battery cartridge can be folded at a predetermined angle in the longitudinal direction of the battery cartridge and/or in the transverse direction of the battery cartridge. Although the battery cartridge can be folded at a predetermined angle by rotating the shaft, the mechanical shaft and the battery cartridge require external auxiliary equipment, resulting in a bulky overall volume.

For another example, the utility model patent of publication No. CN204732468U discloses "a folding soft-packaged power battery group", a plurality of soft-packaged monomer electricity cores (being the battery) of this group battery, every all be equipped with two utmost point ears on the soft-packaged monomer electricity core, it is a plurality of establish ties or connect in parallel through the conductor between the soft-packaged monomer electricity core, the conductor with soft-packaged monomer electricity core between be the welding, the conductor is the conductor of soft collapsible material. Although the battery pack is a foldable battery pack formed by connecting different battery units, the method needs series-parallel combination of different batteries, and wastes the whole volume.

Alternatively, the battery core may be cut into a shape to form a Flexible battery, such as Bioinspired, Spine-Like, Flexible, Rechargeable Lithium-Ion Batteries with High energy Density, DOI: 10.1002/adma.201704947. The flexible battery is manufactured by cutting a roll core into a specific shape, and the manufacturing method needs to use a special cutting process during production, namely, the existing production process is changed, so that the battery cost is high.

The existing battery can be folded by integrally folding an inner core in the battery, the inner core cannot be thickened, and the integral capacity is lower; according to the proposal, the non-foldable inner core is connected through the flexible conductive metal, the node of the flexible conductive metal is used for realizing folding and flexibility, and finally the node is packaged into a foldable/flexible battery. The battery and the battery inner core can be made thick, and the battery capacity is obviously increased.

The inner cores of the multi-section lithium ion/lithium polymer battery are connected by using a flexible lead, and finally packaged into a battery to prepare the foldable/flexible battery.

Disclosure of Invention

The technical problem solved by the technical scheme provided by the embodiment of the invention is that the inner core of the battery is thin and is not easy to be thickened, so that the overall capacity of the battery is low.

According to an embodiment of the present invention, there is provided a foldable battery including: the battery comprises n battery cores, [ (n-1) × 2] connecting pieces, electrolyte and a shell, wherein two adjacent battery cores are connected through 2 connecting pieces, the connecting pieces are used for respectively connecting a positive current collector and a negative current collector of the two adjacent battery cores, and n is not less than 2 and is an integer; the connecting piece for connecting two adjacent battery cores can be bent and folded.

Wherein the connecting member is made of a flexible conductive metal.

In particular, the flexible conductive metal is selected from one or more of aluminum, copper, nickel, gold or platinum.

In particular, the connection is selected from a flexible conductive metal strip, sheet or foil, preferably a flexible conductive metal strip or sheet.

In particular, the connecting elements are parallel to each other and spaced apart from each other.

The battery inner core is a cube made of a positive current collector, a positive material, a diaphragm, a negative material and a negative current collector by a winding method, a stacking method or other methods.

Particularly, the battery inner core is prepared by a winding method and a stacking method.

The preparation method of the foldable battery provided by the embodiment of the invention comprises the following steps:

step 1, preparing a battery inner core

Preparing n battery cores by adopting a winding method, a stacking method or other methods, wherein the battery cores are cubes made of a positive current collector, a positive material, a diaphragm, a negative material and a negative current collector, and n is an integer and is more than or equal to 2;

step 2, fixed connection processing

Connecting the battery inner cores with each other through a flexible conductive metal connecting piece, wherein the positive current collectors of two adjacent battery inner cores are connected with each other through a flexible conductive metal connecting piece; the negative current collectors are connected with each other through another flexible conductive metal connecting piece;

step 3, packaging treatment

Placing the connected battery inner core into a battery shell/outer membrane; then injecting electrolyte; the battery housing/outer membrane is sealed to form a foldable battery.

Wherein, the battery inner core in the step 1 is prepared by adopting a stacking method and a winding method.

Wherein, in the step 2, the flexible conductive metal is selected from one or more of aluminum, copper, nickel, gold or platinum.

Particularly, the flexible conductive metal of the positive current collector connected with the battery inner core is selected from aluminum, gold or platinum; the flexible conductive metal of the negative current collector connected with the battery inner core is selected from copper, nickel, gold or platinum.

In particular, the connection is selected from a flexible conductive metal strip, sheet or foil, preferably a flexible conductive metal strip or sheet.

Particularly, if the battery inner cores are 2, connecting the positive current collector of the first battery inner core with the positive current collector of the second battery inner core through a flexible conductive metal connecting piece in the step 2; and connecting the negative current collector of the first battery inner core with the negative current collector of the second battery inner core through another flexible conductive metal connecting piece.

Particularly, if the battery cores are 3 pieces in step 2, the connection is performed according to the following steps:

2A, connecting a positive current collector of the first battery inner core with a positive current collector of the second battery inner core through a first flexible conductive metal connecting piece; connecting the negative current collector of the first battery inner core with the negative current collector of the second battery inner core through a second flexible conductive metal connecting piece;

2B, connecting the positive current collector of the second battery inner core with the positive current collector of the third battery inner core through a third flexible conductive metal connecting piece; and connecting the negative current collector of the second battery inner core with the negative current collector of the third battery inner core through a fourth flexible conductive metal connecting piece.

Particularly, if the number of the battery cores is more than 3 in the step 2, the connection is performed according to the following steps:

2A, connecting a positive current collector of the first battery inner core with a positive current collector of the second battery inner core through a first flexible conductive metal connecting piece; connecting the negative current collector of the first battery inner core with the negative current collector of the second battery inner core through a second flexible conductive metal connecting piece;

2B, connecting the positive current collector of the second battery inner core with the positive current collector of the third battery inner core through a third flexible conductive metal connecting piece; connecting the negative current collector of the second battery inner core with the negative current collector of the third battery inner core through a fourth flexible conductive metal connecting piece

And 2C, connecting the battery cores in a sequential and analogical manner until the last battery core is connected.

Wherein, the electrolyte in the step 3 is selected from lithium ion electrolyte or lithium polymer electrolyte; and 3, selecting an aluminum plastic film, a polyethylene film and a polypropylene film as the battery shell/outer film.

According to the embodiment of the invention, the foldable battery is prepared according to the method.

The technical scheme provided by the embodiment of the invention has the following beneficial effects:

1. the inner cores of the existing lithium ion/lithium polymer battery are connected by bendable conductive metal, and the bendable nodes are formed by the flexible conductive metal between the two adjacent battery inner cores which are connected, so that the non-flexible inner cores can be prepared into the foldable/flexible lithium ion/lithium polymer battery. The method can change the current battery production process less, only adds the step of connecting the inner core, and is very easy to popularize and expand the production.

2. The non-foldable inner cores are connected through the flexible conductive metal, folding and flexibility are achieved by means of the node of the flexible conductive metal, and the non-foldable inner cores are packaged into a foldable/flexible battery, so that the thickness of the battery and the thickness of the battery inner cores are increased, and the capacity of the battery is remarkably increased.

3. The foldable battery can be disassembled through digital equipment, and whether the infringement is distinguished from the appearance of the battery easily.

4. The foldable battery can be widely applied to foldable mobile phones, foldable tablet equipment, intelligent watches and other bendable digital equipment.

Drawings

FIG. 1 is a schematic diagram of two inner cores connected by a flexible conductive metal according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a foldable battery provided by an embodiment of the invention before folding, which is formed by connecting and encapsulating two inner cores through a flexible conductive metal;

fig. 3 is a schematic view of a folded foldable battery provided by an embodiment of the present invention;

FIG. 4 is a schematic diagram of a plurality of cores connected by a flexible conductive metal according to another embodiment of the present invention;

fig. 5 is a schematic view of a foldable battery provided by another embodiment of the present invention, which is formed by connecting a plurality of cores through a flexible conductive metal and then packaging;

fig. 6 is a schematic view showing how a foldable battery made of a core according to another embodiment of the present invention is folded.

Description of the reference numerals

1. A foldable battery; 2. a battery inner core; 3. a connecting member; 4. outer shell/outer membrane.

Description of the terms

Inner core: the positive electrode current collector, the positive electrode material, the diaphragm, the negative electrode material and the negative electrode current collector are made into a cube by a winding method, a stacking method or other methods.

Lithium ion/lithium polymer battery: a lithium ion battery or a lithium polymer battery.

Collapsible/flexible: collapsible or flexible.

Detailed Description

The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, and it should be understood that the preferred embodiments described below are only for the purpose of illustrating and explaining the present invention, and are not to be construed as limiting the present invention.