KR102490047B1 - Home energy storage system using small redox flow battery which is convenient for installation and maintenance - Google Patents

Abstract

The present invention relates to a household energy storage system using a small redox flow battery that is easy to install and maintain, and more particularly, to a small building or home by applying a redox flow battery to replace an electric hot water facility for nighttime power It relates to a home energy storage system using a compact redox flow battery that is easy to install and maintain and can respond to various power demands.
According to the present invention, a household energy storage system using a small redox flow battery that is easy to install and maintain is a hot water tank of an electric hot water facility for late night power that stores and uses idle power in the form of thermal energy in a hot water tank at night. It can be directly used for various power demand sources such as hot water supply, lighting, air conditioning, transportation, disaster prevention, etc. in small buildings or homes by replacing redox flow batteries with electrolyzers, and distributed ESS can be utilized and built at home.

Description

Home energy storage system using small redox flow battery which is convenient for installation and maintenance}

The present invention relates to a household energy storage system using a small redox flow battery that is easy to install and maintain, and more particularly, to a small building or home by applying a redox flow battery to replace an electric hot water facility for nighttime power It relates to a home energy storage system using a compact redox flow battery that is easy to install and maintain and can respond to various power demands.

Recently, renewable energy such as solar energy or wind energy has been in the limelight as a method for suppressing greenhouse gas emissions, which is a major cause of global warming, and many studies are being conducted to commercialize and spread these.

However, such renewable energy is greatly influenced by location environment and natural conditions. Moreover, renewable energy has a disadvantage in that energy cannot be continuously and evenly supplied because output fluctuations are severe.

Therefore, in order to even out the energy output, it is important to develop a storage device that can store energy when the output is high and use the stored energy when the output is low. There is a redox flow battery and the like.

Among them, lead-acid batteries are widely used commercially compared to other batteries, but have disadvantages such as low efficiency, maintenance costs due to periodic replacement, and problems in handling industrial waste generated during battery replacement.

And, in the case of NaS battery, it has the advantage of high energy efficiency, but has the disadvantage of operating at a high temperature of 300 ° C. or more.

On the other hand, redox flow batteries have low maintenance costs, can be operated at room temperature, and have characteristics such that capacity and output can be designed independently, so a lot of research has recently been conducted as a mass storage device.

Republic of Korea Patent Publication 10-2020-0055311 Republic of Korea Patent Publication 10-2016-0059974 Republic of Korea Patent Publication 10-2015-0032354

In order to easily install and apply the redox flow battery used in industrial capacity at home, the present invention replaces electric hot water facilities for late-night power with a small redox flow battery, so that it can respond to various power demands in small buildings or homes. And to provide a home energy storage system using a compact redox flow battery that is convenient for maintenance.

In addition, the present invention replaces the hot water tank of an electric hot water facility for nighttime power with an electrolytic cell of a redox flow battery of a similar size, so that it can be immediately used for various power demand such as hot water supply, lighting, air conditioning, transportation, disaster prevention, etc. Installation and maintenance The purpose is to provide a home energy storage system using a convenient small redox flow battery.

In addition, the present invention manufactures the electrolyzer of the redox flow battery in a size that can be easily moved and installed without using separate mechanical equipment, so that it can be installed and moved freely, and there is no risk of explosion or fire. The purpose is to provide a home energy storage system using a compact redox flow battery that is easy to install and maintain.

In order to achieve the above object, a household energy storage system using a compact redox flow battery, which is easy to install and maintain, according to an embodiment of the present invention includes a distribution board through which commercial AC power is introduced into a home from a power system; a bi-directional power conversion module that is connected to the distribution board and converts AC power into DC power and outputs it, or converts DC power into AC power and outputs it; a battery unit installed in a home, charged by receiving DC power output from the power conversion module, or discharging the charged DC power to the power conversion module; a battery management module for monitoring state information of the battery unit; An energy management module for receiving state information of the battery unit, diagnosing a state of the battery unit based on the received state information, and controlling operations of the power conversion module and the battery management module, respectively, The battery unit includes a first electrolytic cell and a second electrolytic cell in which a first electrolyte solution and a second electrolyte solution are respectively stored, and at least one connected to the power conversion module and charged and discharged by an oxidation-reduction reaction between the first electrolyte solution and the second electrolyte solution. It is characterized in that it includes a stack unit including the above battery cells, and a redox flow battery including a first circulation pump and a second circulation pump respectively supplying a first electrolyte solution and a second electrolyte solution to the stack unit.

The energy management module may control the redox flow battery to be charged using commercial power in the late-night time period to which the late-night electricity rate is applied, and to discharge the redox flow battery in the non-night time period.

According to the present invention, a household energy storage system using a small redox flow battery that is easy to install and maintain is a hot water tank of an electric hot water facility for late night power that stores and uses idle power in the form of thermal energy in a hot water tank at night. By replacing the redox flow battery of the electrolytic cell, it can be immediately used for various power demand sources such as hot water supply, lighting, air conditioning, transportation, and disaster prevention in small buildings or homes.

In addition, the household energy storage system using a small redox flow battery that is easy to install and maintain according to the present invention is manufactured in a size that can be easily moved and installed without using separate mechanical equipment for the electrolyzer of the redox flow battery system Therefore, it is possible to use and build a distributed ESS at home, etc., without the risk of explosion or fire, and it is free to install and move.

In addition, the household energy storage system using a small redox flow battery that is easy to install and maintain according to the present invention responds to the demand for saving electricity rates in general households, thereby reducing power balance management that buffers and distributes late-night power from the construction of a large ESS. It is subdivided into general households and system distribution is possible.

In addition, the household energy storage system using the compact redox flow battery, which is easy to install and maintain, according to the present invention can be relatively easily achieved through a combination of existing stack units in a method of increasing output.

1 is a block diagram showing a household energy storage system using a compact redox flow battery that is easy to install and maintain according to the present invention.
Figure 2 is a perspective view showing a battery unit of a household energy storage system using a compact redox flow battery that is convenient to install and maintain according to the present invention.

Hereinafter, a household energy storage system equipped with a compact redox flow battery that is easy to install and maintain according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 to 3 show a household energy storage system equipped with a compact redox flow battery that is easy to install and maintain according to the present invention. 1 to 3, a household energy storage system equipped with a compact redox flow battery that is convenient for installation and maintenance according to the present invention includes a distribution panel 10, a power conversion module 20, and a battery unit 30 ), a battery management module 50, and an energy management module 60.

The distribution panel 10 is a part where commercial AC power is introduced into the home from the power system 7, and is connected to a distribution box, a meter 11 installed in the distribution box, a main circuit breaker connected to the meter 11, and a main circuit breaker. It is configured to include a main busbar, a plurality of sub-busbars connected to the main busbar, and a plurality of sub-wire breakers having one side connected to the sub-busbar and the other side connected to the load (L) side.

The power conversion module 20 is connected to the sub-circuit breaker of the distribution panel 10 and converts AC power supplied from commercial power into DC power and outputs it to the battery unit 30 described later, or supplied from the battery unit 30. It converts DC power into AC power and outputs it to the load (L) or commercial power system. The power conversion module 20 may include an AC/DC converter, a DC/AC inverter, and a DC/DC converter.

The battery unit 30 is installed in a certain space in the home, and is charged by receiving DC power output from the power conversion module 20, or the charged DC power is discharged to the power conversion module 20.

The battery unit 30 may include a vanadium redox flow battery 40 in which charging and discharging are performed by exchanging charges while two electrolytes containing vanadium ions flow between membranes.

The redox flow battery 40 includes a first electrolysis tank 41 and a second electrolysis tank 42, a first supply line and a second supply line, a first circulation pump 43 and a second circulation pump 44 , a stack unit 45, and a first recovery line and a second recovery line.

The first electrolytic bath 41 and the second electrolytic bath 42 are preferably manufactured in a much smaller size than the electrolyte tank of the redox flow battery 40 used for industrial purposes. For example, it is preferable that the first electrolytic tank 41 and the second electrolytic tank 42 be freely installed and moved by manufacturing them in a size corresponding to that of a hot water tank of an electric hot water facility using late-night power at home.

The first supply line has one end connected to the first electrolytic bath 41 and the other end connected to the stack unit 45 to supply the first electrolyte stored in the first electrolytic bath 41 to the stack unit 45 . A first circulation pump 43 for pumping and supplying the first electrolyte to the stack unit 45 is installed in the first supply line.

The second supply line has one end connected to the second electrolytic bath 42 and the other end connected to the stack unit 45 to supply the second electrolyte stored in the second electrolytic bath 42 to the stack unit 45 . A second circulation pump 44 for pumping and supplying the second electrolyte to the stack unit 45 is installed in the second supply line.

The stack unit 45 is connected to the power conversion module 20 and includes at least one or more battery cells in which charging and discharging are performed by a redox reaction between the first electrolyte and the second electrolyte.

The stack unit 45 includes an ion exchange membrane 45A, a first electrode plate 46, a second electrode plate 47, and a first electrode plate 46 disposed on opposite sides of the ion exchange membrane 45A, respectively. A first separator and a second separator disposed outside the second electrode plate 47, respectively, and a flow path disposed outside the first separator and the second separator and through which the first electrolyte and the second electrolyte could flow The first and second euro frames are respectively formed, the first and second collector plates are disposed outside the first and second euro frames, and the first and second collector plates are disposed outside the first and second collector plates, respectively. The first end plate 48 and the second end plate 49 may be included.

Although not shown in the drawing, each of the first separator and the second separator may include a main layer, a first cover layer, a second cover layer, and a plurality of supports.

The main layer replaces the existing graphite bulk electrode plate, and is formed of carbon felt with internal voids, has a certain thickness, and is formed in a rectangular shape.

The first cover layer is bonded by heat compression or heat to one side of the opposite sides of the main layer, and is formed of a conductive resin. The first cover layer may be formed of conductive polyethylene (PE).

The second cover layer is formed of a thermoplastic resin by being compressed or bonded by heat to the other surface of the main layer on which the first cover layer is pressed or pressed, among opposite sides of the main layer. The second cover layer may be formed of thermoplastic polyethylene (PE).

The support is buried inside the main layer between the first cover layer and the second cover layer, and a plurality of supports are buried at positions spaced apart from each other by a predetermined interval. Supports are arranged and buried in an N×M matrix pattern or zigzag pattern inside the main layer.

The support is made of polyethylene (PE) and may be formed in a polygonal column or column shape, but in this embodiment, a column shape was applied. In addition, a coating layer coated with polyether ether ketone (PEEK) is further provided on the surface of the support.

Polyether ether ketone (PEEK), which forms the coating layer formed on the surface of the support, has excellent electrical properties such as dielectric permittivity and volume resistivity at high temperatures, can be used without changing physical properties under high temperature and high pressure conditions, and can be used without general thermoplastic resin processing equipment. It is an easily processable, semi-crystalline resin that guarantees excellent stability in a wide range of inorganic and organic chemicals. In addition, it has excellent lubricity under a wide range of conditions, excellent self-lubrication even in the absence of oil and grease supply, and excellent wear resistance. In addition, injection molding, extrusion molding, and powder coating are possible, and it is very advantageous for mass production as well as various small-volume products.

The support is fixed by heat-sealing, heat-compressing, or heat-sealing the coating layers at both ends in the longitudinal direction toward both sides in the thickness direction of the main layer and at both ends of the main layer by being drawn into the first cover layer and the second cover layer at a predetermined depth, respectively. Alternatively, both ends of the support in the longitudinal direction may be fixed to the surfaces of the first cover layer and the second cover layer by thermal fusion, thermal compression, or thermal bonding.

On the other hand, a hollow part may be formed inside the support body along the longitudinal direction, and a core part may be formed by filling the inside of the hollow part with a filler made of PEEK constituting the coating layer described above. In this case, the support body is filled in the hollow part. Durability and strength can be further improved by the core part.

Such a stack unit 45 has a power withdrawal function by forming a connection portion capable of connecting a cable for power withdrawal to a separator plate, and a current collector can be omitted from a stack structure of an existing redox flow battery, and a cable A DLC-coated protective layer may be formed on the surface of the connecting portion to be connected to improve wear resistance and friction characteristics of the connecting portion.

In addition, by inserting and embedding a support for reinforcement inside the carbon felt of the separator, the resin sheet and the carbon felt are thermally compressed, and then the separator is deformed or the strength is weakened or the strength is weakened during cooling. It is easy to handle and has no deformation even during manufacturing due to its size.

In addition, the first and second separators withstand heat generated when the first and second cover layers are thermally compressed or thermally bonded to the main layer through a support having a PEEK coating layer resistant to heat, so that the main layer has a certain thickness. By reinforcing the main layer to have an advantage of manufacturing a separator having various thicknesses and areas along the length of the support.

That is, separators having different thicknesses can be manufactured using supports of different lengths, and even if the main layer is formed of carbon felt, since the support is inserted and buried inside the main layer, the main layer is reinforced by the support and maintains its shape continuously. It can be maintained as, through which the separator can be manufactured in a large area.

The battery management module 50 is for monitoring state information of the battery unit 30 and ensuring safe operation and performance, and protects the battery unit 30 from overheating or overcharging by monitoring the voltage, current, temperature, etc. of the battery unit 30 .

The energy management module 60 is responsible for the overall control of the system, and in detail, receives state information of the battery unit 30, diagnoses the state of the battery unit 30 based on the received state information, and converts power. The operation of the module 20 and the battery management module 50 are respectively controlled.

The energy management module 60 may set the maximum charge amount and maximum discharge amount of the battery unit 30 , charge time zone and discharge time zone setting, and set the operation of the power conversion module 20 .

The energy management module 60 controls the redox flow battery 40 to be charged using commercial power in the late-night time zone to which the late-night electricity rate is applied, and the redox flow battery 40 to be discharged in the non-night time zone. can

For example, from 23:00 pm to 9:00 am the next day, which is a late night time in winter, power is supplied from commercial power and supplied to the redox flow battery 40 to reduce the electrolyte and store power, and in non-night time, redox flow battery By discharging power by oxidizing the electrolyte of (40), self-stored power can be supplied to various consumers in the home without using commercial power during non-night time.

As described above, the household energy storage system using the compact redox flow battery, which is easy to install and maintain, according to the present invention stores the idle power at night in the form of thermal energy in a hot water tank and uses the hot water of the electric hot water facility for night power. By replacing the tank with an electrolytic cell of a similar size redox flow battery, it can be immediately used for various power demand sources such as hot water supply, lighting, air conditioning, transportation, and disaster prevention in small buildings or homes.

In addition, the household energy storage system using a small redox flow battery that is easy to install and maintain according to the present invention is manufactured in a size that can be easily moved and installed without using separate mechanical equipment for the electrolyzer of the redox flow battery system Therefore, it is possible to use and build a distributed ESS at home, etc., without the risk of explosion or fire, and it is free to install and move.

In addition, the household energy storage system using a small redox flow battery that is easy to install and maintain according to the present invention responds to the demand for saving electricity rates in general households, thereby reducing power balance management that buffers and distributes late-night power from the construction of a large ESS. It is subdivided into general households and system distribution is possible.

In addition, the household energy storage system using the compact redox flow battery, which is easy to install and maintain, according to the present invention can be relatively easily achieved through a combination of existing stack units in a method of increasing output.

The household energy storage system using the compact redox flow battery, which is easy to install and maintain according to the present invention described above, has been described with reference to the accompanying drawings, but this is only exemplary, and those skilled in the art Those who grow up will understand that various modifications and other equivalent embodiments are possible from this.

Therefore, the scope of true technical protection of the present invention should be determined only by the technical spirit of the appended claims.

10: distribution panel
20: power conversion module
30: battery unit
40: redox flow battery
41: first electrolysis tank
42: second electrolysis tank
43: first circulation pump
44: second circulation pump
45: stack part
50: battery management module
60: energy management module

Claims (2)

a distribution board through which commercial AC power is introduced into the home from the power system;
a bi-directional power conversion module that is connected to the distribution board and converts AC power into DC power and outputs it, or converts DC power into AC power and outputs it;
a battery unit installed in a home, charged by receiving DC power output from the power conversion module, or discharging the charged DC power to the power conversion module;
a battery management module for monitoring state information of the battery unit;
An energy management module that receives state information of the battery unit, diagnoses the state of the battery unit based on the received state information, and controls operations of the power conversion module and the battery management module, respectively.
The battery unit is connected to a first electrolytic bath and a second electrolytic bath in which a first electrolyte solution and a second electrolyte solution are stored, respectively, and the power conversion module, and is charged and discharged by an oxidation-reduction reaction between the first electrolyte solution and the second electrolyte solution. A redox flow battery including a stack unit including one or more battery cells, and a first circulation pump and a second circulation pump respectively supplying a first electrolyte solution and a second electrolyte solution to the stack unit,
The stack unit includes an ion exchange membrane, a first electrode plate and a second electrode plate respectively disposed on opposite surfaces of the ion exchange membrane, and a first separator plate disposed outside the first electrode plate and the second electrode plate, respectively. and a second separation plate, a first flow path frame and a second flow path frame disposed outside the first separation plate and the second separation plate and having flow paths through which the first electrolyte and the second electrolyte may flow, respectively; A first collector plate and a second collector plate disposed outside the first and second euroframes, respectively, and a first end plate and a second end plate disposed outside the first and second collector plates, respectively including,
Each of the first separation plate and the second separation plate includes a main layer formed of carbon felt having internal voids formed therein, and a first cover layer and a second cover respectively pressed or bonded to one surface and the other surface of the main layer facing each other. A layer and a plurality of layers embedded in the main layer between the first cover layer and the second cover layer at predetermined intervals and a support having a coating layer coated with polyether ether ketone on the surface,
The separation plate of the stack part is provided with a connection part capable of connecting a cable for power withdrawal, and a DLC-coated protective layer is formed on the surface of the connection part. energy storage system. According to claim 1,
The energy management module charges the redox flow battery using commercial power in the late-night time zone to which the late-night electricity rate is applied, and controls the redox flow battery to be discharged in the non-night time zone. Installation and A home energy storage system using a small redox flow battery that is easy to maintain.

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