BATTERY MODULE, BATTERY RACK COMPRISING SAME BATTERY MODULE, AND POWER STORAGE DEVICE

A battery module includes a battery cell assembly having a plurality of battery cells stacked on each other, a pair of end plates provided at both front and rear sides of the battery cell assembly, a pair of buffer plates provided to the pair of end plates and disposed at both front and rear sides of the battery cell assembly; and at least one pressing plate provided between the pair of buffer plates and disposed between the battery cells of the battery cell assembly. The pair of buffer plates and the at least one pressing plate are configured such that front surfaces and rear surfaces thereof in a front and rear direction of the battery cell assembly have a flat shape.

TECHNICAL FIELD

The present disclosure relates to a battery module, and a battery rack and an energy storage system including the battery module.

The present application claims priority to Korean Patent Application No. 10-2020-0008780 filed on Jan. 22, 2020 in the Republic of Korea, the disclosures of which are incorporated herein by reference.

BACKGROUND ART

Secondary batteries which are highly applicable to various products and exhibit superior electrical properties such as high energy density, etc. are commonly used not only in portable devices but also in electric vehicles (EVs) or hybrid electric vehicles (HEVs) driven by electrical power sources. The secondary battery is drawing attentions as a new energy source for enhancing environment friendliness and energy efficiency in that the use of fossil fuels can be reduced greatly and no byproduct is generated during energy consumption.

Secondary batteries widely used at present include lithium ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries and the like. An operating voltage of the unit secondary battery cell, namely a unit battery cell, is about 2.5V to 4.5V. Therefore, if a higher output voltage is required, a plurality of battery cells may be connected in series to configure a battery pack. In addition, depending on the charge/discharge capacity required for the battery pack, a plurality of battery cells may be connected in parallel to configure a battery pack or a battery rack. Thus, the number of battery cells included in the battery pack or the battery rack may be variously set according to the required output voltage or the demanded charge/discharge capacity.

Meanwhile, when a plurality of battery cells are connected in series or in parallel to configure a battery pack, it is common to configure a battery module including at least one battery cell first, and then configure a battery pack or a battery rack by using at least one battery module and adding other components.

The conventional battery module is generally configured to include at least one pressing plate between battery cells in order to minimize damage to the battery module when cell swelling occurs. The at least one conventional pressing plate is generally an EPP foam-type member and includes a plurality of protruding structures having an embossing shape.

However, in the conventional battery module, when cell swelling occurs at the battery cells, pressurization deviation may be generated among the battery cells due to uneven pressurization by the pressing plate including such an embossing-type structure.

If cell swelling occurs in the conventional battery module, the structural stability of the battery module is weakened due to pressurization deviation by the pressing plate, and battery lifespan performance is also deteriorated.

Therefore, there is a need to find a way for providing a battery module capable of minimizing pressurization deviation among battery cells, enhancing structural stability and increasing battery lifespan performance when cell swelling occurs, and a battery rack and an energy storage system including the battery module.

DISCLOSURE

Technical Problem

The present disclosure is directed to providing a battery module, which may minimize pressurization deviation among battery cells, and providing a battery rack and an energy storage system including the battery module.

In addition, the present disclosure is directed to providing a battery module, which may reinforce structural stability, and providing a battery rack and an energy storage system including the battery module.

Moreover, the present disclosure is directed to providing a battery module, which may improve battery lifespan performance, and providing a battery rack and an energy storage system including the battery module.

Technical Solution

In one aspect of the present disclosure, there is provided a battery module, comprising: a battery cell assembly having a plurality of battery cells stacked on each other; a pair of end plates provided at both front and rear sides of the battery cell assembly; a pair of buffer plates provided to the pair of end plates and disposed at both front and rear sides of the battery cell assembly; and at least one pressing plate provided between the pair of buffer plates and disposed between the battery cells of the battery cell assembly, wherein the pair of buffer plates and the at least one pressing plate are configured such that front surfaces and rear surfaces thereof in a front and rear direction of the battery cell assembly have a flat shape.

The pressing plate may be provided in plural, and the plurality of pressing plates may be disposed between the battery cells, respectively, to make a surface contact with a facing battery cell.

At least one of the pair of buffer plates may be configured to make a surface contact with a facing battery cell of the battery cell assembly.

The battery module may further comprise a support plate disposed between the battery cell assembly and any one of the buffer plates.

The support plate may be configured such that a front surface and a rear surface thereof in a front and rear direction of the battery cell assembly have a flat shape.

The support plate may be configured to make a surface contact with a facing battery cell of the battery cell assembly.

The pair of buffer plates may be made of an insulating material.

The pair of buffer plates and the at least one pressing plate may be provided as expanded polypropylene members.

In addition, the present disclosure further provides a battery rack, comprising: at least one battery module according to the above embodiments; and a rack case configured to accommodate the at least one battery module.

Moreover, the present disclosure further provides an energy storage system, comprising at least one battery rack according to the above embodiments.

Advantageous Effects

According to various embodiments as above, it is possible to provide a battery rack and an energy storage system including the battery module.

In addition, according to various embodiments as above, it is possible to provide a battery module, which may reinforce structural stability, and providing a battery rack and an energy storage system including the battery module.

Moreover, according to various embodiments as above, it is possible to provide a battery module, which may improve battery lifespan performance, and providing a battery rack and an energy storage system including the battery module.

BEST MODE

The present disclosure will become more apparent by describing in detail the embodiments of the present disclosure with reference to the accompanying drawings. It should be understood that the embodiments disclosed herein are illustrative only for better understanding of the present disclosure, and that the present disclosure may be modified in various ways. In addition, for ease understanding of the present disclosure, the accompanying drawings are not drawn to real scale, but the dimensions of some components may be exaggerated.

FIG. 1is a diagram for illustrating a battery module according to an embodiment of the present disclosure,FIG. 2is a perspective view showing the battery module ofFIG. 1, from which a module case is excluded,FIG. 3is an exploded perspective view showing a main part of the battery module ofFIG. 2,FIG. 4is a diagram for illustrating a front buffer member of a buffer plate, employed at the battery module ofFIG. 3,FIG. 5is a diagram for illustrating a rear buffer member of the buffer plate, employed at the battery module ofFIG. 3,FIG. 6is a diagram for illustrating a pressing plate, employed at the battery module ofFIG. 3, andFIG. 7is a diagram for illustrating a support plate, employed at the battery module ofFIG. 3.

Referring toFIGS. 1 to 7, a battery module10may include a module case100, a battery cell assembly200, an end plate300, a buffer plate400, a pressing plate500, and a support plate600.

The module case100forms the appearance of the battery module10, and may accommodate the module case100, the battery cell assembly200, the end plate300, the buffer plate400, the pressing plate500and the support plate600, explained later.

The battery cell assembly200is accommodated in the module case100and may include a plurality of battery cells210stacked on each other. The battery cell assembly200may include the plurality of battery cells210, a plurality of cell cartridges230, and a base plate250.

The plurality of battery cells210are secondary batteries and may be provided as a pouch-type secondary battery, a rectangular secondary battery or a cylindrical secondary battery. Hereinafter, in this embodiment, it will be described that the plurality of battery cells210are provided as pouch-type secondary batteries.

The plurality of cell cartridges230may support the plurality of battery cells210. The plurality of cell cartridges230may support one or more battery cells210and may be stacked on each other along a stacking direction of the plurality of battery cells210.

The base plate250may support the plurality of cell cartridges230. To this end, the base plate250may have an area capable of supporting all of the plurality of cell cartridges230.

The end plate300may be provided in a pair. The pair of end plates300may be provided at both front and rear sides of the battery cell assembly200, respectively.

The buffer plate400may be provided in a pair. The pair of buffer plates400are provided to the pair of end plates300and may be disposed at both front and rear sides of the battery cell assembly200.

The pair of buffer plates400may be formed such that considerable areas of front surfaces and rear surfaces thereof in the stacking direction of the battery cell assembly200, namely a front and rear direction of the battery cell assembly200, have a flat shape. Here, at least one of the pair of buffer plates400may make a surface contact with a facing battery cell210of the battery cell assembly200.

The pair of buffer plates400may be made of an insulating material. The pair of buffer plates400may be provided as expanded polypropylene (EPP) members.

The pair of buffer plates400may include a front buffer member410and a rear buffer member430.

The front buffer member410may be provided to a rear surface of the end plate300disposed at the front among the pair of end plates300.

The rear buffer member430may be provided to a front surface of the end plate300disposed at the rear among the pair of end plates300. Meanwhile, the rear buffer member430may include a cable passage435through which a cable member such as an electric cable or sensing cable for connecting electric components of the battery module10may pass.

The pressing plate500is provided between the pair of buffer plates400and may be disposed between the battery cells210of the battery cell assembly200.

The pressing plate500may be formed such that considerable areas of a front surface and a rear surface thereof in the stacking direction of the battery cell assembly200, namely in the front and rear direction of the battery cell assembly200, have a flat shape.

Here, the pressing plate500may be disposed between the battery cells210, respectively, to make a surface contact with a facing battery cell210.

At least one pressing plate500or a plurality of pressing plates500may be provided. Hereinafter, in this embodiment, it will be described that the pressing plate500is provided in plural.

The plurality of pressing plates500may be made of an insulating material. The plurality of pressing plates500may be provided as expanded polypropylene (EPP) members.

The support plate600may be disposed between the battery cell assembly200and any one of the buffer plates400. Specifically, the support plate600may be disposed between the battery cell assembly200and the rear buffer member430of the buffer plate400.

The support plate600may be configured such that a front surface and a rear surface thereof in the front and rear direction of the battery cell assembly200have a flat shape. The support plate600may make a surface contact with a facing battery cell210of the battery cell assembly200.

Hereinafter, when cell swelling occurs at the battery cells210of the battery cell assembly200of the battery module10according to this embodiment, a mechanism for eliminating pressurization deviation among the battery cells210will be described in more detail.

FIGS. 8 to 13are diagrams for illustrating a mechanism for eliminating pressurization deviation among battery cells when cell swelling occurs at the battery cells of a battery cell assembly, employed at the battery module ofFIG. 1.

Referring toFIGS. 8 and 9, in the battery module10, a cell swelling phenomenon may occur at the battery cells210of the battery cell assembly200. According to the cell swelling phenomenon, cell expansion may occur in the front and rear direction of the battery cells210, which is the stacking directions of the battery cells210.

When cell swelling occurs, the plurality of pressing plates500according to this embodiment may uniformly press the facing front and rear surfaces of the battery cells210while making a surface contact with the facing battery cells210.

Referring toFIGS. 10 and 11, when the cell swelling occurs at the battery cells210of the battery cell assembly200of the battery module10, the front buffer member410of the buffer plate400may also uniformly press the facing front surface of the battery cell210while making a surface contact with the facing battery cell210.

Referring toFIGS. 12 and 13, when cell swelling occurs at the battery cells210of the battery cell assembly200of the battery module10, the rear buffer member430of the buffer plate400may uniformly press the facing rear surface of the battery cell210while making a surface contact with the facing battery cell210, together with the support plate600. In particular, the support plate600may supplement the surface contact pressing force near the cable passage435of the rear buffer member430.

As described above, in this embodiment, since the battery cells210may be pressed more effectively by means of the buffer plate400, the pressing plate500and the support plate600when cell swelling occurs at the battery cells210, the pressurization deviation among the battery cells210may be effectively minimized.

In this embodiment, since the pressurization deviation among the battery cells210is eliminated, it is possible to further enhance the structural stability of the battery module10and further improve the lifespan performance of the battery module10.

FIG. 14is a diagram for illustrating a battery rack according to an embodiment of the present disclosure.

Referring toFIG. 9, a battery rack1may include the plurality of battery modules10of the former embodiment, and a rack case50for accommodating the plurality of battery modules10.

Since the battery rack1of this embodiment includes the battery module10of the former embodiment, the battery rack1may have all advantages of the battery module10of the former embodiment.

FIG. 15is a diagram for illustrating an energy storage system according to an embodiment of the present disclosure.

Referring toFIG. 15, an energy storage system E may be used for home or industries as an energy source. The energy storage system E may include at least one battery rack1of the former embodiment, or a plurality of battery racks1in this embodiment, and a rack container C for accommodating the plurality of battery racks1.

Since the energy storage system E of this embodiment includes the battery rack1of the former embodiment, the energy storage system E may have all advantages of the battery rack1of the former embodiment.

According to various embodiments as above, it is possible to provide a battery module10, which may improve manufacture efficiency, secure product reliability and control cell swelling, and to provide a battery rack1and an energy storage system E including the battery module10.

While the embodiments of the present disclosure have been shown and described, it should be understood that the present disclosure is not limited to the specific embodiments described, and that various changes and modifications can be made within the scope of the present disclosure by those skilled in the art, and these modifications should not be understood individually from the technical ideas and views of the present disclosure.