KR101542072B1 - Energy Storage System with Variable Capacity and Device Comprising the Same - Google Patents

Abstract

The present invention relates to a variable capacity energy storage system and an apparatus including the variable capacity energy storage system, and more particularly, to an energy storage system including lithium secondary battery cells or unit modules capable of being charged and discharged as a unit cell, An inverter connected in parallel to the battery modules, and an external case for accommodating the battery modules therein and accommodating or mounting the inverters inside the battery module. Energy storage systems and devices incorporating them.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a variable capacity energy storage system,

The present invention relates to a variable capacity energy storage system and an apparatus including the variable capacity energy storage system, and more particularly, to an energy storage system including lithium secondary battery cells or unit modules capable of being charged and discharged as a unit cell, An inverter connected in parallel to the battery modules, and an external case for accommodating the battery modules therein and accommodating or mounting the inverters inside the battery module. Energy storage systems and devices incorporating them.

In recent years, energy storage systems (Energy Storage System) have been attracting attention in line with the expansion of new and renewable energy, especially in developed countries. Unlike existing thermal power and nuclear power generation, renewable energy such as wind power and solar power generation fluctuates very much in the amount of power that can be generated depending on the external environment such as the wind intensity and the amount of sunshine. Therefore, the energy storage system is a device that stores the generated energy and supplies it to the power system in a stable manner at the required time, and the energy storage system is emerging as an indispensable facility.

In addition, energy storage systems can save energy when power demand is low, and can improve power quality and energy use efficiency by supplying power during overload or emergency.

Examples of such energy storage systems include domestic energy storage systems, industrial or commercial medium and large energy storage systems, and large capacity energy storage systems installed in power plants and substations.

In particular, residential energy storage systems and industrial or commercial medium energy storage systems are rapidly growing in size, coupled with smart grid technology that enables suppliers and consumers to exchange information to optimize energy efficiency.

Among them, the market for existing household energy storage systems is replacing lead acid batteries with lithium secondary batteries, which have high energy density and high output power, in the configuration of battery inverters and lead acid batteries for lead acid batteries that have been used in the past. Is accelerating.

However, although the use of the energy storage system using such a lithium secondary battery is rapidly increasing, the domestic energy storage system using the lithium secondary battery is in short supply of the technology for organically increasing the capacity of the system due to the variation of the required power amount. to be.

Therefore, there is a high need for a technique capable of fundamentally solving such problems.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and the technical problems required from the past.

The inventors of the present application have conducted intensive research and various experiments, and have consequently found that two or more battery modules including a plurality of standardized small capacity unit cells are accommodated in an external case capable of variable size, It has been confirmed that the capacity of the system can be easily increased according to the required amount of power when the power source is connected, and the present invention has been accomplished.

Accordingly, the energy storage system according to the present invention is an energy storage system comprising lithium secondary battery cells or unit modules capable of being charged and discharged as a unit cell, the energy storage system comprising: at least two battery modules including one or more unit cells; An inverter connected in parallel to the battery modules, and an external case for accommodating the battery modules therein and accommodating the inverters therein or mounting the inverters to the outside.

In the conventional home energy storage system, there is a lack of technology that can facilitate expansion and reduction of capacity according to various purposes. Therefore, in order to change the capacity due to the fluctuation of the required power amount, There was a burden to occur.

Accordingly, the inventors of the present application have recognized these problems and have conducted intensive researches. After the in-depth study, the inventors of the present application stored two or more battery modules each including one or more standardized small capacity unit cells in an external case In the case of parallel connection with an inverter supporting the same voltage band as a single battery module, it is not only necessary to replace the inverter according to the change of the capacity of the system, but also the power capacity of the system can be easily increased without changing the equipment Respectively.

In one specific example, the case may be of a structure in which the size of the energy storage system is changed according to the number of the battery modules housed therein for changing the capacity of the energy storage system. In particular, The variable structure can be a structure that can be further inserted or removed.

In one specific example, the receiving part may be formed with a receiving member in the form of a bar at both ends of the inner side wall of the outer case so that the left and right ends of the battery modules can be mounted. Since the bar-shaped receiving member as described above forms a receiving portion having an open top and bottom, the air can be introduced, and the heat radiation effect of the battery module can be enhanced.

In one specific example, the end of the receiving member may have a structure in which a fastening protrusion or a fastening groove is formed to fix the battery modules so that a plurality of battery modules are not damaged by an external impact.

The outer case may be, for example, a structure for stacking in the vertical direction, a structure for mounting in the horizontal direction, or a structure for both of them.

In the case where the outer case is stacked in the vertical direction, since a plurality of battery modules can be vertically mounted on a narrow site, it is difficult to mount a battery module having a large load on the upper side, The work may not be easy, and safety may also be a problem as the height of the outer case increases. Further, in the case of a horizontal mounting structure, it can be easily installed, but there is a disadvantage that a large space may be required. Therefore, the outer case is not limited, but a structure that can be mounted in both the vertical direction and the horizontal direction is preferable.

In one specific example, the outer case may be a rack or a cabinet. The rack can be largely comprised of a frame and a plurality of shelves, the frame including a plurality of vertical columns, a cover or loop located at the top layer, a bottom layer at the bottom, And can be configured as a receiving portion.

The racks can typically be made of steel, cold rolled steel, or stainless steel, but are not limited thereto.

In one specific example, the inverter may be a battery inverter for a lead-acid battery, and the inverter may convert the direct-current voltage to an alternating-current voltage or convert the alternating-current voltage to a direct-current voltage. For example, the inverter converts an alternating current transmitted from the outside into a direct current and stores it in a battery module. When the stored electric power is used, the inverter performs a function of converting a direct current of the battery module into an alternating current.

In addition, the inverter can support a voltage range equal to the voltage range of one battery module, and more specifically, a voltage range ranging from 50 to 100V.

In one specific example, the energy storage system may further include a DC distribution box, a sensor, a circuit breaker, and a battery management system (BMS).

In one specific example, the battery module may have a capacity of 1 to 5 kWh. When the capacity of the battery module is less than 1 kWh, a plurality of small-capacity battery modules need to be assembled in order to construct an energy storage system having a required amount of power, so that more assembling members are required, and the assembling process becomes long and complicated. On the other hand, when the capacity of the battery module exceeds 5 kWh, the amount of power required for constructing the energy storage system can not be precisely adjusted, which is not preferable.

In one specific example, the rack may include at least two battery modules, and the number of battery modules that can be mounted according to the height of the rack may vary. In detail, although the number of the battery modules is not particularly limited, it is preferable that 2 to 18 batteries are electrically connected in parallel. The positive and negative terminals of the battery modules may be connected in parallel to the inverter. Therefore, it is unnecessary to replace the inverter when the battery module is added or removed.

In one specific example, the electrical connections of the battery modules and the inverter can be achieved by a wire or a bus-bar

In one specific example, the energy storage system may have a capacity of 2 to 85 kWh. When the capacity of the energy storage system is less than 2 kWh, the capacity may be insufficient to provide the amount of power required for a general household. On the other hand, when the capacity of the energy storage system exceeds 85 kWh, Which increases equipment cost and is not suitable for residential energy storage systems.

In one specific example, the lithium secondary battery cell may have a cylindrical structure, a prismatic structure, or a pouch structure, and more specifically, a battery cell of a pouch structure. The pouch-type battery cell is preferable because it can make a battery pack having a more compact structure than that of the battery pack.

The present invention also provides a device comprising the energy storage system as a power source.

The device can be used for household power supply, public utility power supply, large-sized shop power supply, emergency power supply, computer room power supply, portable power supply, medical equipment power supply, fire extinguishing equipment power supply, But the scope of application is not limited to these.

The structure and manufacturing method of such a device are well known in the art, so a detailed description thereof will be omitted herein.

As described above, the energy storage system according to the present invention provides a battery module having the same voltage band and operating voltage range supported by the battery inverter, and an external case capable of changing the size variably, It is possible to easily increase the power capacity of the battery, and since a plurality of small capacity battery modules are connected in parallel to the inverter, it is not necessary to replace the inverter according to the equipment change, .

1 is a schematic diagram illustrating an energy storage system including two battery modules in accordance with one embodiment of the present invention;
2 is a schematic diagram illustrating an energy storage system including four battery modules in accordance with one embodiment of the present invention;
3 is a schematic diagram illustrating an energy storage system including eight battery modules in accordance with one embodiment of the present invention;
4 is a front view of an energy storage system showing a structure in which two battery modules are mounted in a rack according to one embodiment of the present invention;
5 is a front view of an energy storage system showing a structure in which four battery modules are mounted in a rack according to one embodiment of the present invention;
6 is a perspective view of an energy storage system showing a structure in which four battery modules are mounted in a rack according to one embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings, but the present invention is not limited by the scope of the present invention.

1 to 3 are schematic views illustrating two or more battery modules, an electrical connection structure, and other components of an energy storage system according to an embodiment of the present invention.

In particular, FIG. 1 schematically illustrates an energy storage system 100 having two battery modules 110 embedded therein according to one embodiment of the present invention.

Referring to FIG. 1, an energy storage system 100 includes battery modules 110, an inverter 120, a DC distribution box 150, and a wire 140. The positive terminal 111 of the battery modules 110 is connected to the positive terminal 121 of the inverter 120 via the DC distribution box 150 and the negative terminal 112 of the battery modules 110 is connected to the positive terminal 121 of the inverter 120. [ Is connected to the negative terminal 122 of the inverter 120 via the DC distribution box 150 and the battery modules 110 are built in the case 130.

Electrical connection between the battery modules 110 and the DC battery module 110, the DC distribution box 150, and the inverter 120 can be easily achieved with the wire 140.

FIG. 2 schematically illustrates an energy storage system 200 in which four battery modules 210 are embedded according to an embodiment of the present invention.

Referring to FIG. 2, the energy storage system 200 includes an outer case 230 having a variable size to facilitate capacity increase, and four battery modules 210 housed in the outer case 230, The DC distribution box 250 disposed outside the outer case 230 is connected between the battery modules 210 and the inverter 220 in parallel Respectively.

The inverter 220 disposed outside the outer case 230 is a lead-acid battery inverter 220 that supports the same voltage band as the operating voltage range of one battery module 210, .

FIG. 3 schematically illustrates an energy storage system 300 in which eight battery modules 310 are embedded according to an embodiment of the present invention.

3, the energy storage system 300 includes an outer case 330 having a size larger than the case 230 of FIG. 2, and the eight battery modules 310 are connected to each other by using wires 340 The DC power distribution box 350 and the battery module 311 adjacent to the inverter 320 disposed in the lowest layer of the external case 330 are also electrically connected in parallel using the wire 340 .

In the case where the inverter 320 and the DC distribution box 350 are incorporated in the case 330 of FIG. 3, the space can be effectively utilized and the installation work can be simplified.

4 to 6 schematically show an energy storage system in which the outer case is a rack.

4 is a front view showing a structure in which two battery modules 430 are mounted on a rack 401 according to an embodiment of the present invention.

Referring to FIG. 4, a plurality of battery modules 430 are housed in a housing portion formed in the rack 401.

In Fig. 4, for convenience of explanation, one receiving portion formed inside the rack 401 is represented by a dotted line.

411 and 412 and 413 in the form of a bar are arranged at predetermined distances in the inside of the rack 401 so as to have a predetermined thickness so as to mount the left and right ends of the battery modules 430 And is provided at both ends of the side wall of the rack 401.

At the ends of the housing members 410, 411, 412, and 413, fastening protrusions 420, 421, 422, and 423 protruding in a predetermined size in the vertical direction are provided so as to accommodate and fix the battery modules 430 Respectively.

The rack 401 can easily separate the inverter 450 or the storage part of the battery modules so that the battery capacity of the system 400 can be increased or decreased. Thus, the frame 401, which can house one battery module 430, And a structure in which the set 460 can be additionally stacked between the accommodating portion of the inverter 450 and the accommodating portion of the uppermost battery module 430. Thus, the rack 401 is structured to increase or decrease the magnitude of the amount of power required accordingly.

The inverter 450 is disposed in the lowest layer of the rack 401 and is electrically connected in parallel to the battery module 430 located at the bottom of the battery modules 430.

Specifically, the positive terminal 431 of the battery module 430 is electrically connected to the positive terminal 451 of the inverter 450 using the wire 440, and the negative terminal 432 of the battery module 430 is electrically connected to the positive terminal 451 of the inverter 450. [ Is electrically connected to the negative electrode terminal 452 of the inverter 450 by a wire 440.

It goes without saying that a DC distribution box (not shown) may be installed between the lowermost battery module 430 and the inverter 450.

5 is a front view showing a structure in which four battery modules 530 are mounted on a rack 501 according to an embodiment of the present invention.

Referring to FIG. 5, the energy storage system 500 may be formed by adding two frame sets 560 in the rack 401 of FIG.

In the rack 401, four battery modules 530 are housed in respective storage portions, and one inverter 550 is accommodated in the lowest storage portion.

511, 512, 513, 514, 515, 516, 517, 518, and 519 are formed in the rack 501 at predetermined spacing distances, and the accommodating members 510, 511, 512, 513, 515, 515, 516, 517, 518, and 519 are provided with fastening protrusions 520, 521, 522, 523, and 523 projecting in a predetermined size in the vertical direction so as to receive and fix the battery modules 530, 524, 525, 526, 527, 528, and 529 are formed.

6 is a perspective view illustrating a structure in which battery modules 530 according to an embodiment of the present invention are mounted in a rack 501. FIG.

5 and 6, the rack 501 includes frames 570, 571, and 572 that are the main axes of the rack, a loop 580 that encloses the upper layer of the rack 501, and a lower base 590 And a plurality of through holes 573 are formed in some frames 570 and 572 to facilitate the heat generated in the battery module 530. [

The housing members 510 and 515 are formed in a bar shape so that the center portion 530 surrounded by the housing members 510 and 515 and the frame 572 can move air And the like.

For simplicity, the DC distribution boxes of FIGS. 4-6 are shown in simplified form in an abbreviated form.

It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (16)

1. An energy storage system comprising rechargeable lithium secondary battery cells or unit modules as unit cells,
Two or more battery modules including at least one unit cell;
An inverter connected in parallel to the battery modules; And
An external case for accommodating the battery modules therein and for accommodating or mounting the inverter therein;
And,
The outer case is configured to vary in size according to the number of battery modules housed therein.
The external case includes a housing portion in which the battery modules are housed, and the external case has a structure in which the battery modules are stacked in the vertical direction,
The external case is a rack formed of a frame and shelves. The rack includes a structure in which each storage unit can be separated so as to increase or decrease the battery capacity of the system. And a structure capable of further stacking a frame set capable of accommodating the battery module between the storage portion of the inverter and the storage portion of the uppermost battery module. The energy storage system according to claim 1, wherein the lithium secondary battery cell has a cylindrical structure, a prismatic structure, or a pouch structure. The energy storage system according to claim 1, wherein the capacity of one of the battery modules is 1 to 5 kWh. The energy storage system according to claim 1, wherein the inverter is a battery inverter for a lead-acid battery. 5. The energy storage system of claim 4, wherein the lead-acid battery inverter supports a voltage band in the range of 50 to 100V. The energy storage system according to claim 1, wherein an operating voltage range of the battery module is equal to a voltage range supported by the inverter. 2. The energy storage system of claim 1, wherein the energy storage system has a capacity of 2 to 85 kWh. The energy storage system according to claim 1, wherein 2 to 18 batteries are electrically connected in parallel. The energy storage system according to claim 8, wherein the positive terminals and the negative terminals of the battery modules are connected in parallel to the inverter. 2. The energy storage system of claim 1, wherein the electrical connections of the battery modules and the inverter are accomplished by a wire or a bus-bar. The energy storage system according to claim 1, wherein the receiving portion is formed with a fastening protrusion or a fastening groove for fixing the battery modules. delete delete delete A device as claimed in any of the preceding claims, comprising an energy storage system as a power source. 16. The system of claim 15, wherein the device is a home power supply, a public utility power supply, a large shop power supply, an emergency power supply, a computer room power supply, a portable power supply, a medical power supply, Or evacuation facility power supply.

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