Patent Description:
In an ESS including a plurality of battery cells, if an abnormality such as a short circuit occurs in some battery cells, the temperature of the battery cells continuously rises. As a result, if the temperature of the battery cells exceeds a critical temperature, a thermal runaway phenomenon occurs. If a thermal runaway phenomenon occurs in some battery cells, safety issues may arise.

If a flame is generated in a battery module including the battery cell due to the thermal runaway phenomenon occurring in some battery cells, the temperature of neighboring battery modules rises rapidly, which may propagate the thermal runaway phenomenon to the entire ESS within a short time.

As a result, if the thermal runaway phenomenon occurring in some battery cells is not quickly handled, the damage caused by the thermal runaway may be expanded to the battery module, which is a battery unit with a larger capacity than the battery cell, or to a sub ESS including a plurality of battery modules. If the expansion of damage caused by the thermal runaway is not appropriately handled, this may lead to disasters such as ignition and explosion of the battery module and the sub ESS, which may cause not only property damage but also safety issues.

Therefore, when flame occurs due to thermal runaway in some battery cells inside the battery module, it is important to block the expansion of the flame generation range inside the sub ESS. In addition, if the flame is already expanded entirely inside one sub ESS, it is important to increase the efficiency of fire extinguishing and cooling so that the flame does not move to sub ESSs adjacent to the sub ESS where the flame is generated.

Further prior art is described in <CIT> and <CIT>.

The present disclosure is designed to solve the problems of the related art, and therefore the present disclosure is directed to performing proper extinguishing and cooling when the flame is expanded entirely inside one sub ESS, so that the flame does not move to sub ESSs adjacent to the sub ESS where the flame is generated.

In addition, the present disclosure is directed to performing proper extinguishing and cooling so that flame is not propagated to neighboring battery modules, when the flame is generated in some battery modules included in one sub ESS.

However, the technical object to be solved by the present disclosure is not limited to the above, and other objects not mentioned herein will be clearly understood by those skilled in the art from the following disclosure.

In one aspect of the present disclosure, there is provided an ESS (Energy Storage System), comprising: a sub ESS stack including a plurality of sub ESSs, each having a plurality of battery modules and a battery rack for accommodating the plurality of battery modules; an ESS housing configured to accommodate the plurality of sub ESSs; a sensor installed in the ESS housing to sense at least one of temperature and smoke inside the ESS housing; a first blocking sheet interposed between the sub ESSs adjacent to each other; a fire extinguishing device configured to supply a fire extinguishing agent into the ESS housing; and a cooling device configured to supply a cooling water to the first blocking sheet.

The first blocking sheet is a superabsorbent sheet.

The first blocking sheet may include a superabsorbent fiber capable of absorbing and containing <NUM> to <NUM> of cooling water per <NUM>.

The battery module may include a cell stack formed by stacking a plurality of battery cells; and a module housing configured to accommodate the cell stack.

The plurality of battery modules may be stacked up and down inside the battery rack.

The ESS may further comprise at least one second blocking sheet interposed between the battery modules adjacent to each other along an upper and lower direction inside the battery rack.

The second blocking sheet may be disposed to penetrate through the battery rack and traverse from one side of the sub ESS stack in a stacking direction to the other side thereof.

The first blocking sheet may have a first coupling slit, and the second blocking sheet may be inserted into the first coupling slit and coupled to the first blocking sheet.

The second blocking sheet may have a second coupling slit, and the first blocking sheet may be inserted into the second coupling slit and coupled to the second blocking sheet.

The second blocking sheet may be a superabsorbent sheet.

The second blocking sheet may include a superabsorbent fiber capable of absorbing and containing <NUM> to <NUM> of cooling water per <NUM>.

The superabsorbent fiber may include a superabsorbent resin containing at least one of a starch-based material, a cellulose-based material and a synthetic polymer-based material.

The ESS may further comprise a control device configured to control the operation of the fire extinguishing device and the cooling device by referring to at least one of the information about temperature and the information about smoke generation, sensed by the sensor.

According to an embodiment of the present disclosure, it is possible to perform proper extinguishing and cooling when the flame is expanded entirely inside one sub ESS, so that the flame does not move to sub ESSs adjacent to the sub ESS where the flame is generated.

In addition, according to an embodiment of the present disclosure, it is possible to perform proper extinguishing and cooling so that flame is not propagated to neighboring battery modules, when the flame is generated in some battery modules included in one sub ESS.

Therefore, the description proposed herein is just a preferable example for the purpose of illustrations only.

An ESS (Energy Storage System) according to an embodiment of the present disclosure will be described with reference to <FIG>.

First, referring to <FIG>, the ESS according to an embodiment of the present disclosure includes a plurality of sub ESSs <NUM>, an ESS housing <NUM>, a first blocking sheet <NUM>, a fire extinguishing device <NUM>, a cooling device <NUM> and a sensor <NUM>.

The sub ESS <NUM> includes a battery rack <NUM> and a plurality of battery modules <NUM> accommodated in the battery rack <NUM>. The battery rack <NUM> has open front and rear surfaces. The plurality of sub ESSs <NUM> are arranged side by side in a left and right directions so that the side surfaces of the battery racks <NUM> face each other, thereby forming one sub ESS stack.

Referring to <FIG>, the plurality of battery modules <NUM> are stacked in an upper and lower direction inside the battery rack <NUM> to form one module stack.

Referring to <FIG>, the battery module <NUM> includes a plurality of battery cells <NUM>, a bus bar frame <NUM>, a module housing <NUM>, an air inlet <NUM> and an air outlet <NUM>.

The battery cell <NUM> is provided in plural, and the plurality of battery cells <NUM> are stacked to form one cell stack. As the battery cell <NUM>, a pouch-type battery cell may be applied, as an example. The battery cell <NUM> includes a pair of electrode leads 121a, which are respectively drawn to both sides in a longitudinal direction.

The bus bar frame <NUM> is provided in a pair, and the pair of bus bar frames <NUM> cover one side and the other side of the cell stack in a width direction, respectively. The electrode lead 121a of the battery cell <NUM> is drawn out through a slit formed at the bus bar frame <NUM> and may be bent and electrically connected by the bus bar frame <NUM>.

The module housing <NUM> has a substantially rectangular parallelepiped shape and accommodates the cell stack therein. The air inlet <NUM> and the air outlet <NUM> are formed at one longitudinal side and the other longitudinal side of the module housing <NUM>.

The air inlet <NUM> is formed at one side of the cell stack in the stacking direction, namely at one longitudinal side of the battery module <NUM>, and is formed in the form of a hole through the module housing <NUM>. The air outlet <NUM> is formed at the other side of the cell stack in the stacking direction, namely at the other longitudinal side of the battery module <NUM>, and is formed in the form of a hole through the module housing <NUM>.

The air inlet <NUM> and the air outlet <NUM> are located at opposite sides diagonally along the longitudinal direction of the battery module <NUM>.

Meanwhile, an empty space is formed between the bus bar frame <NUM> and the module housing <NUM>. That is, an empty space is formed between one of six outer surfaces of the module housing <NUM>, which faces one longitudinal side and the other longitudinal side of the battery cell <NUM>, and the bus bar frame <NUM> so that air for cooling the battery cell <NUM> may flow therethrough. The empty space is formed at both sides of the battery module <NUM> in the width direction.

The air inlet <NUM> is formed at a position corresponding to the empty space formed at one side of the battery module <NUM> in the width direction, and the air outlet <NUM> is formed at a position corresponding to the empty space formed at the other side of the battery module <NUM> in the width direction.

In the battery module <NUM>, the air introduced into the battery module <NUM> through the air inlet <NUM> cools the battery cell <NUM> while moving from the empty space formed at one side of the battery module <NUM> in the width direction to the empty space formed at the other side of the battery module <NUM> in the width direction, and then is discharged through the air outlet <NUM>. That is, the battery module <NUM> corresponds to an air-cooled battery module.

Since the battery module <NUM> applied to the present disclosure has an air-cooled structure as described above, flame is likely to be ejected out of the module housing <NUM>. That is, if an abnormality occurs in some of the battery cells <NUM> included in the battery module <NUM> so that the temperature inside the battery cells <NUM> rises and thus gas is leaked out by venting, a flame may be generated. The generated flame may be ejected out of the module housing <NUM> through the air inlet <NUM> and the air outlet <NUM>, which are formed for air cooling.

Referring to <FIG>, when an abnormal temperature rise occurs and thus a flame is generated in some battery module <NUM> as described above, the first blocking sheet <NUM> prevents the flame from moving to sub ESSs <NUM> adjacent to the sub ESS <NUM> that includes the battery module <NUM> with the above problem.

To perform the above function, the first blocking sheet <NUM> is interposed between the sub ESSs <NUM> adjacent to each other. The first blocking sheet <NUM> is a super absorbent sheet. That is, the first blocking sheet <NUM> includes a super absorbent fiber, and the superabsorbent fiber may absorb and contain approximately <NUM> to <NUM> of cooling water per <NUM>. The superabsorbent fiber may include, for example, a super absorbent resin (or a super absorbent polymer) including at least one of a starch-based material, a cellulose-based material or a synthetic polymer-based material. The superabsorbent fiber is obtained by spinning a superabsorbent resin into a net form.

If a cooling water supplied from the cooling device <NUM>, the first blocking sheet <NUM> may quickly absorb the cooling water, and the first blocking sheet <NUM> absorbing the cooling water may prevent the abnormal temperature rise and/or the flame occurring in some sub ESS <NUM> from being propagated to neighboring sub ESSs <NUM>.

The first blocking sheet <NUM> preferably has an area corresponding to the side surface of the sub ESS <NUM> in order to minimize the amount of used cooling water and maximize the cooling effect and the flame expansion blocking effect. However, a longitudinal end of the first blocking sheet <NUM> may be exposed to the top of the sub ESS stack in order to quickly absorb the cooling water supplied from the cooling device <NUM>.

Referring to <FIG>, the fire extinguishing device <NUM> sprays the fire extinguishing agent into the ESS housing <NUM> when the internal temperature of the ESS housing <NUM> rises above a reference value and/or smoke is sensed, thereby preventing the occurrence of fire in advance or extinguishing the fire that has already occurred. As the fire extinguishing agent, for example, a clean fire extinguishing agent in the form of a gas such as Novec <NUM> may be applied, and also, nitrogen and solid aerosol may be applied.

The fire extinguishing device <NUM> includes a fire extinguishing agent tank <NUM> installed at an outer side of the ESS housing <NUM> to store the fire extinguishing agent and an extinguishing agent injection tube <NUM> having one side connected to the fire extinguishing agent tank <NUM> and the other side penetrating the ESS housing <NUM>.

If the internal temperature of the ESS housing <NUM> rises above the reference value and/or smoke is sensed due to fire, the cooling device <NUM> sprays the cooling water into the ESS housing <NUM> to prevent the occurrence of fire in advance or extinguish the fire that has already occurred.

More specifically, the cooling device <NUM> sprays the cooling water directly onto the first blocking sheet <NUM>. The cooling device <NUM> includes a cooling water supply tube <NUM> connected to the cooling water tank <NUM> that stores the cooling water, and a plurality of cooling water injection tubes <NUM> branched at an end of the cooling water supply tube <NUM> and disposed at a position corresponding to each first blocking sheet <NUM>.

Even though the drawing of the present disclosure illustrate only the case where the cooling water supply tube <NUM> is located at the outer side of the ESS housing <NUM> and the cooling water injection tube <NUM> passes through the ESS housing <NUM>, the present disclosure is not limited thereto. That is, it is also possible that the cooling water supply tube <NUM> passes through the ESS housing <NUM> and the cooling water injection tube <NUM> is branched from the cooling water supply tube <NUM> inside the ESS housing <NUM>.

Referring to <FIG>, the sensor <NUM> is installed inside the ESS housing <NUM> to sense at least one of temperature and smoke generation inside the ESS housing. That is, the sensor <NUM> corresponds to a temperature sensor and/or a smoke sensor.

Although not shown in the drawings, the information sensed by the sensor <NUM> and/or an alarm according to the sensed information may be displayed through a user interface disposed outside the module housing <NUM>. If a user judges through the sensed information and/or alarm that there is a risk of fire or that a fire has occurred, the user may operate the fire extinguishing device <NUM> and the cooling device <NUM> to extinguish or prevent the fire inside the ESS.

Meanwhile, referring to <FIG>, the ESS according to an embodiment of the present disclosure may further include a control device <NUM>, in addition to the above-described components. The control device <NUM> controls the operation of the fire extinguishing device <NUM> and the cooling device <NUM> by referring to the information about temperature and/or the information about smoke generation sensed by the sensor <NUM>.

That is, the control device <NUM> is an element applied to achieve automation of fire extinguishing and/or cooling by allowing the fire extinguishing device <NUM> and the cooling device <NUM> to operate without user manipulation when certain conditions are satisfied. The reference temperatures for operating the fire extinguishing device <NUM> and the cooling device <NUM> may be determined in consideration of the number of the sub ESSs <NUM>, the number of battery modules <NUM> included in the sub ESS <NUM>, the number of battery cells <NUM> included in the battery module <NUM>, the capacity of the battery cell <NUM>, and the like.

Next, an ESS according to another embodiment of the present disclosure will be described with reference to <FIG>.

The ESS according to another embodiment of the present disclosure is different from the ESS of the former embodiment only in that a second blocking sheet <NUM> is additionally applied, and other components are substantially the same. Accordingly, in describing the ESS according to another embodiment of the present disclosure, the second blocking sheet <NUM> will be described in detail, and other components already described in the former embodiment will not be described in detail again.

Referring to <FIG> and <FIG>, the second blocking sheet <NUM> is interposed between the battery modules <NUM> adjacent to each other along the upper and lower direction inside the battery rack <NUM>. The second blocking sheet <NUM> is disposed to penetrate the side surface of the battery rack <NUM> and traverse from one side of the sub ESS <NUM> in the stacking direction to the other side thereof.

One second blocking sheet <NUM> or a plurality of second blocking sheets <NUM> may be provided. If only one second blocking sheet <NUM> is provided, it is efficient that the second blocking sheet <NUM> is disposed at the center of the battery rack <NUM> along the stacking direction of the battery module <NUM>. The material of the second blocking sheet <NUM> is the same as the first blocking sheet <NUM> described above.

Referring to <FIG>, the first blocking sheet <NUM> and the second blocking sheet <NUM> may be coupled to each other by forming a first coupling slit 300a at each first blocking sheet <NUM> and inserting the second blocking sheet <NUM> into the first coupling slit 300a. In this case, the position and shape of the first coupling slit 300a formed at the first blocking sheet <NUM> correspond to a slit (not shown) formed at the side surface of the battery rack <NUM> for the passage of the second blocking sheet <NUM>.

Referring to <FIG>, the first blocking sheet <NUM> and the second blocking sheet <NUM> may be coupled to each other by forming a second coupling slit 310a at the second blocking sheet <NUM> in a number corresponding to the first blocking sheets <NUM> and inserting the first blocking sheet <NUM> into the second coupling slit 310a, unlike that shown in <FIG>.

As the first blocking sheet <NUM> and the second blocking sheet <NUM> are connected to each other in this way, the first blocking sheet <NUM> may absorb the cooling water supplied from the top of the first blocking sheet <NUM>, and the second blocking sheet <NUM> may absorb a part of the absorbed cooling water again, thereby preventing the thermal runaway phenomenon from expanding along the stacking direction of the sub ESS stacks and the stacking direction of the battery modules <NUM>.

Claim 1:
An ESS (Energy Storage System), comprising:
a sub ESS stack including a plurality of sub ESSs (<NUM>), each having a plurality of battery modules (<NUM>) and a battery rack (<NUM>) for accommodating the plurality of battery modules (<NUM>);
an ESS housing (<NUM>) configured to accommodate the plurality of sub ESSs (<NUM>);
a sensor (<NUM>) installed in the ESS housing (<NUM>) to sense at least one of temperature and smoke inside the ESS housing (<NUM>);
a fire extinguishing device (<NUM>) configured to supply a fire extinguishing agent into the ESS housing (<NUM>),
characterized by
a first blocking sheet (<NUM>) interposed between the sub ESSs (<NUM>) adjacent to each other; and
a cooling device (<NUM>) configured to supply a cooling water to the first blocking sheet (<NUM>),
wherein the first blocking sheet (<NUM>) is a superabsorbent sheet.