阅读说明：本技术 锂离子电池和相应的锂离子电池模组 (Lithium ion battery and corresponding lithium ion battery module ) 是由 刘冠伟 胡晓玮 于 2020-12-11 设计创作，主要内容包括：本发明涉及一种锂离子电池,该锂离子电池至少包括：壳体；布置在所述壳体内部的电芯,在所述电芯中设置有集流体；分别与所述集流体连接的至少一个正极耳和至少一个负极耳；其中,所述锂离子电池还设置有至少一个另外的极耳,所述另外的极耳与所述集流体连接并且配置成用于导出和/或导入热量。本发明还涉及一种相应的锂离子电池模组。能够有效地提高导热率,避免温度过高或过低的问题。(The invention relates to a lithium ion battery, which at least comprises: a housing; a cell disposed inside the housing, a current collector disposed in the cell; at least one positive tab and at least one negative tab connected to the current collector, respectively; wherein the lithium ion battery is further provided with at least one further tab, which is connected with the current collector and is configured for conducting away and/or conducting in heat. The invention also relates to a corresponding lithium ion battery module. The heat conductivity can be effectively improved, and the problem of overhigh or overlow temperature is avoided.)

1. A lithium-ion battery (10) comprising at least:

-a housing (1);

-a cell (2) arranged inside the casing (1), in which cell a current collector (3) is provided;

-at least one positive tab (4) and at least one negative tab (5) connected to said current collector (3), respectively;

wherein the lithium ion battery (10) is further provided with at least one further tab (6) which is connected to the current collector (3) and is configured for conducting away and/or conducting in heat.

2. The lithium ion battery (10) according to claim 1, wherein the further tab (6) is connected in a thermally conductive manner to a heating and/or cooling device (7).

3. The lithium ion battery (10) according to claim 1 or 2, wherein the further tab (6) is located on the same side of the lithium ion battery (10) as the positive tab (4) and/or the negative tab (5), or

The further tab (6) is located on a different side of the lithium ion battery (10) than the positive tab (4) and/or the negative tab (5).

4. The lithium ion battery (10) according to claim 1 or 2, wherein the further tab (6) is made of the same material as the positive tab (4) and/or the negative tab (5); and/or

The positive lug (4) is made of aluminum; and/or

The negative electrode tab (5) is made of nickel or copper nickel plating.

5. The lithium ion battery (10) according to claim 1 or 2, wherein the further tab (6) is connected with the current collector (3) by welding or riveting.

6. The lithium ion battery (10) according to claim 1 or 2, wherein the further tab (3) has a sealing film (9) which is bonded to the housing (1) in a sealing manner when the lithium ion battery (10) is encapsulated.

7. The lithium ion battery (10) according to claim 1 or 2, wherein the current collector (3) comprises a positive current collector (3.1) connected to the positive tab (4) and a negative current collector (3.2) connected to the negative tab (5), on which positive current collector a positive active material layer (8.1) is applied and on which negative current collector a negative active material layer (8.2) is applied, wherein,

the positive current collector (3.1) is configured as an aluminum foil, and/or

The negative current collector (3.2) is configured as a copper foil.

8. The lithium ion battery (10) according to claim 1 or 2, wherein the lithium ion battery (10) is configured as a soft pack lithium ion battery; and/or

The housing (1) is designed as an aluminum foil.

9. A lithium ion battery module (100) comprising at least one lithium ion battery (10) according to one of the preceding claims, wherein the lithium ion battery module (100) has a heating and/or cooling device (7) for connection with a further tab (6) of the lithium ion battery (10).

10. The lithium ion battery module (100) according to claim 9, wherein the lithium ion battery module (100) further has a temperature sensor (20) by means of which a temperature of the lithium ion battery (10) can be detected.

Technical Field

The present invention relates to a lithium ion battery. The invention also relates to a corresponding lithium ion battery module.

Background

Lithium ion batteries have been increasingly used as power sources to replace conventional energy sources due to their advantages of environmental protection, energy conservation, high energy density, etc., and are used in the fields of automobiles, consumer electronics, etc.

However, lithium ion batteries are very temperature sensitive, and can only be charged and discharged efficiently and maintain good performance in a suitable temperature range. For lithium ion batteries, the ideal operating temperature is typically in the range of 15 ℃ to 35 ℃. The higher temperature leads the aging speed and the thermal resistance increasing speed of the lithium ion battery to be accelerated, thereby leading the service life to be shortened, and even causing the problems of thermal runaway and the like of the battery; while lower temperatures result in decreased conductivity, decreased ionic activity and decreased battery capacity of the electrolyte of lithium ion batteries.

In order to avoid the above problems and to keep the lithium ion battery in a stable temperature range, it is common in the prior art to utilize a heat sink or heat spreader in large-area contact with the housing or aluminum plastic film of the lithium ion battery for heat exchange. However, this measure not only significantly increases the thickness of the lithium ion battery, but also fails to achieve the desired temperature control effect due to low thermal conductivity in the thickness direction. In addition, there is also a technical scheme of conducting heat by using the positive and negative electrode tabs, but this increases the design difficulty of the positive and negative electrode tabs and may adversely affect the conductivity of the positive and negative electrode tabs.

Disclosure of Invention

It is therefore an object of the present invention to provide an improved lithium ion battery which is capable of effectively increasing the thermal conductivity, avoiding the problem of too high or too low a temperature, and thus always operating in a desired temperature range. Furthermore, the lithium ion battery can be manufactured simply and cost-effectively without affecting the positive and negative electrode tabs. The invention also aims to provide a corresponding lithium ion battery module.

According to a first aspect of the present invention, there is provided a lithium ion battery comprising at least:

-a housing;

-a cell arranged inside the casing, in which cell a current collector is provided;

-at least one positive tab and at least one negative tab connected to said current collector, respectively;

wherein the lithium ion battery is further provided with at least one further tab, which is connected with the current collector and is configured for conducting away and/or conducting in heat.

In contrast to the prior art, the lithium ion battery according to the invention conducts heat inside the lithium ion battery out of the battery or into the battery in the direction of extension of the current collector by means of at least one further tab which is directly connected to the current collector. Here, due to the continuity and high thermal conductivity of the current collector of the lithium ion battery in the extending direction of the current collector, the heat exchange capacity of the lithium ion battery can be effectively improved, and the situation that the temperature is too high or too low can be avoided. In addition, the arrangement of the at least one additional tab does not affect other components of the lithium ion battery, such as the positive and negative tabs. The lithium ion battery according to the invention can therefore be produced simply and cost-effectively.

According to an exemplary embodiment of the invention, the further tab is connected in a thermally conductive manner to a heating device and/or a cooling device.

According to an exemplary embodiment of the invention, the further tab is located on the same side of the lithium ion battery as the positive tab and/or the negative tab, or the further tab is located on a different side of the lithium ion battery than the positive tab and/or the negative tab.

According to an exemplary embodiment of the invention, the further tab is made of the same material as the positive tab and/or the negative tab; and/or the positive lug is made of aluminum; and/or the negative electrode lug is made of nickel or copper nickel plating.

According to an exemplary embodiment of the invention, the further tab is connected to the current collector by welding or riveting.

According to an exemplary embodiment of the invention, the further tab has a sealing film which is bonded to the housing in a sealing manner during the encapsulation of the lithium ion battery.

According to an exemplary embodiment of the present invention, the current collector includes a positive electrode current collector connected to the positive electrode tab and a negative electrode current collector connected to the negative electrode tab, a positive electrode active material layer is disposed on the positive electrode current collector, and a negative electrode active material layer is disposed on the negative electrode current collector, wherein the positive electrode current collector is configured as an aluminum foil, and/or the negative electrode current collector is configured as a copper foil.

According to an exemplary embodiment of the invention, the lithium ion battery is configured as a soft pack lithium ion battery; and/or the housing is constructed as an aluminum plastic film.

A second aspect of the invention provides a lithium ion battery module comprising at least one lithium ion battery according to the invention, wherein the lithium ion battery module has a heating and/or cooling device for connection to a further tab of the lithium ion battery.

According to an exemplary embodiment of the invention, the lithium ion battery module further has a temperature sensor by means of which the temperature of the lithium ion battery can be detected.

Drawings

The principles, features and advantages of the present invention may be better understood by describing the invention in more detail below with reference to the accompanying drawings. The drawings comprise:

fig. 1 shows a schematic diagram of a lithium ion battery according to an exemplary embodiment of the present invention;

FIG. 2 shows a cross-sectional view of the lithium-ion battery of FIG. 1 along section line A-A;

FIG. 3 shows a schematic diagram of a lithium-ion battery according to an alternative exemplary embodiment of the present invention;

fig. 4 shows a schematic diagram of a lithium ion battery module according to an exemplary embodiment of the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings and exemplary embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the scope of the invention.

Fig. 1 shows a schematic diagram of a lithium-ion battery 10 according to an exemplary embodiment of the present invention. The lithium ion battery 10 is here configured as a soft-packed lithium ion battery, i.e. a polymer housing is provided on a liquid lithium ion battery. Of course, it is also conceivable for the lithium ion battery 10 to be designed as a metal-encased lithium ion battery, for example as a steel-encased or aluminum-encased lithium ion battery. Compared with a lithium ion battery with a metal shell, the soft package lithium ion battery has the advantages of good safety, light weight, long cycle life, flexible design and the like.

As shown in fig. 1, the lithium ion battery 10 has a case 1. The housing 1 is here configured as an aluminum foil by way of example. Inside the casing 1, a cell 2 containing an electrolyte for conducting electrons between the positive and negative electrodes of the battery, which electrolyte is composed of an organic solvent, an electrolyte (lithium salt), and an additive, for example, is arranged. The battery cell 2 also has a separator configured to separate positive and negative electrodes of the battery and prevent the positive and negative electrodes from contacting a short circuit, the separator being capable of passing electrolyte ions and being exemplarily configured as an organic solvent-resistant high-strength thinned polyolefin porous film. The diaphragm is not shown in the figures for the sake of summary.

As shown in fig. 1, a current collector 3 is further disposed in the battery cell 2, and the current collector 3 is configured to collect the current generated by the battery active material and form a large current to be output to the outside. The current collector 3 is exemplarily configured as a metal foil and separated as a positive current collector and a negative current collector by a separator, which is further illustrated in fig. 2.

As shown in fig. 1, the current collectors 3 are connected to one positive tab 4 and one negative tab 5 on both sides of the lithium ion battery 10, respectively. The positive tab 4 and the negative tab 5 extend beyond the casing 1 and function as a positive electrode and a negative electrode, respectively, of the lithium ion battery 10. Here, it is also conceivable to provide any number of positive electrode tabs or negative electrode tabs that are considered to be meaningful to those skilled in the art.

The positive electrode tab 4 is made of aluminum, for example, and a dense oxide film is formed on the aluminum surface of the positive electrode tab 4 at high positive electrode potentials and corrosion is thereby avoided.

The negative electrode tab 5 is made of nickel or copper nickel plating, by way of example, whereby a good welding effect can be advantageously achieved while maintaining a low resistance.

Illustratively, the positive tab 4 and the negative tab 5 are each fixedly connected to the current collector 3 by welding, such as ultrasonic welding, laser welding, or friction welding. Further, it is also conceivable to connect the positive and negative electrode tabs and the current collector 3 together by bolting or riveting.

The positive tab 4 and the negative tab 5 are each formed by a metal strip and a sealing film, i.e., a sealing film is applied to both sides of the metal strip of the tabs, and the sealing film is hermetically bonded to the housing 1, which is formed by an aluminum plastic film in an exemplary manner, by heating when the lithium ion battery 10 is packaged, thereby advantageously preventing electrolyte leakage and avoiding a short circuit between the metal strip of the positive tab and the housing 1, which is further illustrated in fig. 2.

As shown in fig. 1, the lithium ion battery 10 is also provided with at least one further tab 6, which is arranged on a different side of the lithium ion battery 10 with respect to the positive tab 4 and the negative tab 5 and extends beyond the housing 1. The further tab 6 is likewise connected to the current collector 3 and is configured to conduct away heat from the interior of the lithium ion battery 10 and/or to conduct external heat into the lithium ion battery 10. Due to the continuity of the current collector 3 in the direction of extension of the current collector and the high thermal conductivity, a rapid transfer of heat via the further tab 6 and the current collector 3 is possible, as a result of which the temperature of the lithium ion battery 10 can advantageously be rapidly regulated and the lithium ion battery 10 can always be operated in the desired temperature range. Furthermore, the additional tab 6 does not function as an electrode and does not adversely affect the existing positive and negative tabs 4 and 5, which reduces the design difficulty of the lithium ion battery 10 and enables standardization and cost-effective manufacturing of the lithium ion battery 10.

The further tab 6 is connected in a thermally conductive manner, for example, to a heating and/or cooling device 7. Here, the heating device and the cooling device may be configured as an integrated component, and may be configured to generate heat when the temperature is too low and to discharge heat when the temperature is too high. For example, the heating device and the cooling device may also be designed separately from one another and each be connected in a thermally conductive manner to the further tab 6. In this case, the heating and/or cooling device 7 can be assigned to the lithium ion battery 10 itself, but it is also conceivable for the heating and/or cooling device 7 to be assigned to the environment outside the lithium ion battery 10 or to the lithium ion battery module. The heating device is configured as a film heating sheet and the cooling device as a heat sink fin or a fan, for example, although other heating and cooling devices considered appropriate by those skilled in the art are also contemplated. By connecting the further tab 6 to the heating and/or cooling device 7, a more efficient introduction and/or removal of heat from the lithium ion battery 10 can be achieved.

Fig. 2 shows a cross-sectional view of the lithium ion battery 10 of fig. 1 along the section line a-a.

As shown in fig. 2, the current collector 3 comprises a positive current collector 3.1 connected to the positive tab 4 and a negative current collector 3.2 connected to the negative tab 5. Illustratively, the positive current collector 3.1 is configured as an aluminum foil, while the negative current collector 3.2 is configured as a copper foil. However, the configuration of foamed aluminum, porous aluminum layer, copper mesh, nickel foil, porous stainless steel, etc. may be considered accordingly by those skilled in the art for positive current collector 3.1 and/or negative current collector 3.2 as desired.

As shown in fig. 2, a positive electrode active material layer 8.1 is applied on both sides of the positive electrode current collector 3.1, and a negative electrode active material layer 8.2 is applied on both sides of the negative electrode current collector 3.2, wherein the positive electrode active material layer 8.1 is exemplarily composed of lithium iron phosphate, lithium cobaltate or lithium manganate, and the negative electrode active material layer 8.2 is exemplarily composed of a carbon negative electrode material, a tin-based negative electrode material or a lithium-containing transition metal nitride negative electrode material. Here, the positive electrode current collector 3.1 and the negative electrode current collector 3.2 are separated by a not-shown separator.

As shown in fig. 2, the positive electrode collector 3.1 and the negative electrode collector 3.2 are each connected to a further tab 6 in order to achieve temperature regulation. Of course, it is also conceivable for only one of the two current collectors to be connected to a further tab 6, or for both current collectors to be connected to at least one further tab 6.

The further tab 6 is made, for example, of the same material as the positive tab 4 and/or the negative tab 5, as a result of which the further tab 6 can be produced cost-effectively and the connection of the further tab 6 to the current collector 3 is simplified. Illustratively, the further tab 6 connected to the positive current collector 3.1 is made of the material of the positive tab 4, for example aluminum, while the further tab 6 connected to the negative current collector 3.2 is made of the material of the negative tab 5, for example nickel.

The further tab 6 is also connected to the current collector 3 by welding or riveting, which may be, for example, ultrasonic welding, laser welding or friction welding. This enables the additional tab 6 and the current collector 3 to be connected in the same process step in the process step of connecting the positive tab 4 and/or the negative tab 5 and the current collector 3, thereby reducing the process steps and significantly reducing the process cost.

As shown in fig. 2, the further tabs 6 each project from the housing 1. Sealing films 9 are applied to both sides of the further tab 6 at the location of contact with the housing 1, which sealing films are bonded to the housing 1 by heating during the encapsulation of the lithium ion battery 10, so that the further tab 6 is sealed and insulated from the housing 1.

Fig. 3 shows a schematic diagram of a lithium-ion battery 10 according to an alternative exemplary embodiment of the present invention.

As shown in fig. 3, positive electrode tab 4 and negative electrode tab 5 are disposed on the same side of lithium ion battery 10. It is of course also conceivable for the positive electrode tab 4 and the negative electrode tab 5 to be arranged on adjacent sides or on opposite sides of the lithium ion battery 10. It is also contemplated that any number of positive and negative lugs deemed significant by one skilled in the art may be provided as desired.

As shown in fig. 3, one additional tab 6 is provided on the same side, adjacent side, and opposite side with respect to the positive electrode tab 4 and the negative electrode tab 5, respectively. It is also contemplated that any number of additional tabs 6 deemed significant by one skilled in the art may be provided on each side of the lithium ion battery 10 as desired. In this case, the further tabs 6 can have, for example, the same or suitably modified shapes and dimensions as required.

Fig. 4 shows a schematic diagram of a lithium ion battery module 100 according to an exemplary embodiment of the present invention.

As shown in fig. 4, the lithium ion battery module 100 includes at least one, e.g., three lithium ion batteries 10, which can be connected in parallel or in series. The lithium ion battery module 100 further comprises at least one heating and/or cooling device 7, which is connected in a thermally conductive manner to the further tabs 6 of the respective lithium ion batteries 10, so that all lithium ion batteries 10 in the lithium ion battery module 100 can be thermally managed by means of the heating and/or cooling device 7.

Illustratively, the lithium ion battery module 100 also has a temperature sensor 20 configured to detect the temperature of the lithium ion battery 10. By comparing the temperature detected by the temperature sensor 20 with the preset ideal operating temperature, it can be reliably and quickly determined whether it is necessary to activate the heating means to generate heat or activate the cooling means to discharge heat. This enables the lithium ion battery 10 in the lithium ion battery module 100 to be always within the normal operating temperature range.

The preceding explanations of embodiments describe the invention only in the framework of said examples. Of course, the individual features of the embodiments can be freely combined with one another as far as technically expedient, without departing from the framework of the invention.

Other advantages and alternative embodiments of the present invention will be apparent to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, representative structures, and illustrative examples shown and described. On the contrary, various modifications and substitutions may be made by those skilled in the art without departing from the basic spirit and scope of the invention.