Patent Description:
Currently, commercially available secondary batteries include nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, lithium secondary batteries and the like, and among them, lithium secondary batteries have little or no memory effect, and thus they are gaining more attention than nickel-based secondary batteries for their advantages that recharging may be done whenever it is convenient, the self-discharge rate is very low and the energy density is high.

A lithium secondary battery primarily uses lithium-based oxide and a carbon material as a positive electrode active material and a negative electrode active material respectively. The lithium secondary battery includes an electrode assembly including a positive electrode plate and a negative electrode plate coated with the positive electrode active material and the negative electrode active material respectively with a separator interposed between the positive electrode plate and the negative electrode plate, and a packaging or a battery pouch case in which the electrode assembly is hermetically received together with an electrolyte solution.

Recently, secondary batteries are widely used in not only small devices such as portable electronic devices, but also medium- and large-scale devices such as vehicles and energy storage systems. For use in medium- and large-scale device applications, many secondary batteries are electrically connected to increase the capacity and output. In particular, pouch-type secondary batteries are widely used in medium- and large-scale devices due to their easy-to-stack advantage.

More recently, with the use as a source of energy and the growing need for large-capacity structures, there is an increasing demand for a battery rack including a plurality of battery packs, each including a plurality of secondary batteries electrically connected in series and/or in parallel, a battery module in which the plurality of secondary batteries is received, and a battery management system (BMS).

The battery rack typically includes a metal rack case to protect the plurality of battery packs from external impacts or receive and store the battery packs. Recently, with the increasing demand for high capacity battery racks, the demand for battery racks including a plurality of battery packs is increasing.

However, when thermal runaway occurs in a secondary battery of any one of the plurality of battery packs in the battery rack and the secondary battery burns or explodes, a larger explosion may occur due to the transfer of heat or flames to adjacent secondary batteries, so there have been many attempts to prevent the subsequent fires or explosions.

Accordingly, there is a need for quick and complete fire extinguishing technology to rapidly handle thermal runaway when it occurs in a secondary battery within the battery rack.

When a fire or thermal runaway occurs in any of the plurality of battery packs, the fire has been suppressed by feeding the fire extinguishing liquid to the battery pack in which the fire or thermal runaway occurred, but the fire extinguishing liquid is fed to a battery pack in which the fire did not occur and thus the corresponding battery pack is contaminated with the fire extinguishing liquid and cannot be re-used.

Further prior art is described in <CIT>, <CIT>, <CIT> (forming the basis for the preamble of claim <NUM>) , and <CIT>.

The present disclosure is designed to solve the above-described problem, and therefore the present disclosure is directed to providing a battery rack for effectively preventing the spread of a fire or heat and re-using an undamaged battery pack when the fire or thermal runaway occurs while in use.

These and other objects and advantages of the present disclosure may be understood by the following description, and will be apparent from the embodiments of the present disclosure.

To achieve the above-described object, a battery rack according to the present disclosure includes a plurality of battery packs vertically arranged, each battery pack including a plurality of secondary batteries stacked in a direction, and a pack housing having an internal space to receive the plurality of secondary batteries and having a feed port for supplying a fire extinguishing liquid from a fire extinguishing liquid tank to said battery pack when an internal temperature in said battery pack equals or rises above a predetermined temperature, and a rack case having a receiving space to receive the plurality of battery packs, and including a plurality of rack plates, each having a mounting surface on which the battery pack is mounted, the mounting surface sloping at a predetermined angle with declining height as it goes in the sloping direction, and an extension portion having an end in the sloping direction extending further outward than the lower battery pack.

The rack case may include a front frame disposed at a front end of the plurality of battery packs and including a post configured to support the ground, a rear frame disposed at a rear end of the plurality of battery packs and including a post configured to support the ground, and a fixing bracket coupled to the rack plate and coupled to the post of each of the front frame and the rear frame at a predetermined angle with declining height as it goes in the sloping direction.

The extended end of the extension portion of the lower rack plate among the plurality of rack plates may be disposed at a more inward position than an end of the extension portion of the upper rack plate.

The end in the sloping direction of the lower battery pack among the plurality of battery packs may be disposed at a more inward position than an end of the upper battery pack.

The rack plate may include a stopper to keep the mounted battery pack from moving in the any one direction.

The battery pack may further include a cover having an end in the sloping direction extending further outward than said battery pack to allow the fire extinguishing liquid falling from the upper rack plate to flow outward.

The rack plate may have a guide groove to guide the movement of the fire extinguishing liquid moving out of the pack housing.

The rack plate may include a discharge portion configured to receive the fire extinguishing liquid falling from the upper battery pack and flow it out.

The battery rack may include an absorption member between the secondary batteries in the battery pack to absorb the fire extinguishing liquid.

To achieve the above-described object, an energy storage system according to the present disclosure includes at least one battery rack.

The solution of claim <NUM> prevents the fire extinguishing liquid supplied to the specific battery pack among the plurality of battery packs from flowing into the lower battery pack when thermal runaway or a fire occurs in the specific battery pack. Accordingly, it is possible to solve the problem caused by the supply of the fire extinguishing liquid that is to say, the remaining battery pack except the battery pack in which thermal runaway or a fire occurred is wetted with the fire extinguishing liquid and cannot be re-used.

According to the solution of claim <NUM>, when the fire extinguishing liquid is supplied, the fire extinguishing liquid moving out of the pack housing is discharged through the extension portion, and in this instance, since the extended length of the extension portion disposed at the lower position is shorter than that of the extension portion disposed at the higher position, the lower battery pack may avoid contamination by the fire extinguishing liquid falling in the direction of gravity from the extension portion disposed at the higher position.

According to the solution of claim <NUM>, when the fire extinguishing liquid is supplied to the battery pack, the fire extinguishing liquid moving out of the pack housing does not flow to the lower battery pack and may vertically fall by the gravity. That is, the battery pack may avoid contamination by the fire extinguishing liquid falling in the direction of gravity from the extension portion disposed at the higher position.

The solution of claim <NUM> enables to control the movement of the fire extinguishing liquid to a specific location of the rack plate, and to prevent the fire extinguishing liquid from being fed into the lower battery pack due to the unexpected flow of the fire extinguishing liquid. Accordingly, it is possible to prevent the battery pack in which thermal runaway or a fire did not occur from being contaminated with the fire extinguishing liquid. The present disclosure can re-use the battery pack in which thermal runaway or a fire did not occur.

The accompanying drawings illustrate preferred embodiments of the present disclosure, and together with the following detailed description, serve to provide a further understanding of the technical aspects of the present disclosure. However, the present disclosure should not be construed as being limited to the drawings.

Therefore, the embodiments described herein and illustrations shown in the drawings are just a most preferred embodiment of the present disclosure, but not intended to fully describe the technical aspects of the present disclosure.

<FIG> is a schematic perspective view of a battery rack according to an embodiment of the present disclosure. <FIG> is a schematic rear perspective view of a battery pack of the battery rack according to an embodiment of the present disclosure. <FIG> is a schematic perspective view of a cell assembly of the battery pack of the battery rack according to an embodiment of the present disclosure. For reference, the positive and negative X-axis directions in <FIG> may be right and left directions. The positive and negative Z-axis directions in <FIG> may be up and down directions. The positive and negative Y-axis directions in <FIG> may be rear and front directions.

Referring to <FIG>, the battery rack <NUM> of the present disclosure includes a plurality of battery packs <NUM> vertically arranged and a rack case <NUM>.

Specifically, each battery pack <NUM> may include a plurality of secondary batteries <NUM> stacked in a direction. The secondary battery <NUM> may be a pouch-type secondary battery <NUM>.

In particular, the pouch-type secondary battery <NUM> may include an electrode assembly (not shown), an electrolyte solution (not shown) and a pouch <NUM>.

Each secondary battery <NUM> may stand in a direction that is approximately perpendicular to the ground with two wide surfaces disposed in the front-rear direction and sealing portions disposed in the up, down, left and right directions when viewed from the direction F (shown in <FIG>). In other words, each secondary battery <NUM> may stand upright in the vertical direction. Unless otherwise specified herein, the up, down, front, rear, left, and right directions are defined when viewed from the direction F.

Here, the pouch may have a concave receiving portion. The electrode assembly and the electrolyte solution may be received in the receiving portion. Each pouch may include an outer insulating layer, a metal layer and an inner adhesive layer, and the inner adhesive layers adhere to each other at the edges of the pouch to form the sealing portions. A terrace portion may be formed at each of the left and right ends at which a positive electrode lead <NUM> and a negative electrode lead <NUM> of the secondary battery <NUM> are formed.

The electrode assembly may be an assembly of an electrode plate coated with an electrode active material and a separator, and may include at least one positive electrode plate and at least one negative electrode plate with the separator interposed between. The positive electrode plate of the electrode assembly may have a positive electrode tab, and at least one positive electrode tab may be connected to the positive electrode lead <NUM>.

Here, the positive electrode lead <NUM> may have one end connected to the positive electrode tab and the other end exposed through the pouch, and the exposed portion may act as an electrode terminal of the secondary battery <NUM>, for example, a positive electrode terminal of the secondary battery <NUM>.

The negative electrode plate of the electrode assembly may have a negative electrode tab, and at least one negative electrode tab may be connected to the negative electrode lead <NUM>. The negative electrode lead <NUM> may have one end connected to the negative electrode tab and the other end exposed through the pouch, and the exposed portion may act as an electrode terminal of the secondary battery <NUM>, for example, a negative electrode terminal of the secondary battery <NUM>.

As shown in <FIG>, when viewed from the direction F, the positive electrode lead <NUM> and the negative electrode lead <NUM> may be formed at the left and right ends with respect to the center of the secondary battery <NUM>. That is, the positive electrode lead <NUM> may be provided at one end (the left end) with respect to the center of the secondary battery <NUM>. The negative electrode lead <NUM> may be provided at the other end (the right end) with respect to the center of the secondary battery <NUM>.

For example, as shown in <FIG>, each secondary battery <NUM> of the cell assembly <NUM> may have the positive electrode lead <NUM> and the negative electrode lead <NUM> extending in the left-right direction.

Here, the terms representing the directions such as front, rear, left, right, up, and down may change depending on the position of the observer or the placement of the stated elements. However, in the specification, for convenience of description, the front, rear, left, right, up, and down directions are defined when viewed from the direction F.

According to this configuration of the present disclosure, it is possible to increase the area of the electrode lead in one secondary battery <NUM> without interruption between the positive electrode lead <NUM> and the negative electrode lead <NUM>.

The positive electrode lead <NUM> and the negative electrode lead <NUM> may be formed in a plate shape. In particular, the positive electrode lead <NUM> and the negative electrode lead <NUM> may extend in the horizontal direction (X direction) with the wide surfaces standing upright in the front-rear direction.

Here, the 'horizontal direction' refers to a direction parallel to the ground when the battery pack <NUM> is placed on the ground, and may be referred to as at least one direction on a plane perpendicular to the vertical direction.

However, the battery pack <NUM> according to the present disclosure is not limited to the above-described pouch-type secondary battery <NUM> and may use various types of secondary batteries <NUM> known at the time of filing the application.

The at least two cell assemblies <NUM> may be arranged in the front-rear direction (Y-axis direction).

The battery pack <NUM> may include a busbar assembly <NUM> including at least one busbar <NUM> configured to electrically connect the plurality of secondary batteries <NUM> and a busbar frame <NUM>. Specifically, the busbar <NUM> may have an electrically conductive metal, for example, copper, aluminum and nickel. The busbar frame <NUM> may have a plastic material with low electrical conductivity.

The pack housing <NUM> may have an internal space to receive the cell assembly <NUM> therein. Specifically, when viewed from the direction F of <FIG>, the pack housing <NUM> may include a top cover <NUM>, a base plate <NUM>, a front cover <NUM> and a rear cover <NUM>.

Specifically, the base plate <NUM> may have a larger area than the size of the lower surface of the at least two cell assemblies <NUM> to mount the at least two cell assemblies <NUM> thereon. The base plate <NUM> may be in the shape of a plate that extends in the horizontal direction.

The top cover <NUM> may include an upper wall <NUM> and a side wall <NUM> extending downward from the upper wall <NUM>. The upper wall <NUM> may be in the shape of a plate that extends in the horizontal direction to cover the top of the cell assembly <NUM>. The side wall <NUM> may be in the shape of a plate that extends downward from the left and right ends of the upper wall <NUM> to cover the left and right sides of the cell assembly <NUM>.

The side wall <NUM> may be coupled to a portion of the base plate <NUM>. For example, as shown in <FIG>, the top cover <NUM> may include the upper wall <NUM> in the shape of a plate that extends in the front-rear direction and the left-right direction. The top cover <NUM> may include two side walls <NUM> extending downward from the left and right ends of the upper wall <NUM>. The lower end of each of the two side walls <NUM> may be coupled to the left and right ends of the base plate <NUM>. In this instance, the coupling method may be male-female coupling or weld coupling.

The front cover <NUM> may be configured to cover the front side of the plurality of secondary batteries <NUM>. For example, the front cover <NUM> may be in the shape of a plate having a larger size than the size of the front side of the plurality of secondary batteries <NUM>. The plate may stand in the vertical direction.

The rear cover <NUM> may be configured to cover the rear side of the cell assembly <NUM>. For example, the rear cover <NUM> may be in the shape of a plate having a larger size than the size of the rear side of the plurality of secondary batteries <NUM>.

The pack housing <NUM> may have an internal space to receive the plurality of secondary batteries <NUM>, and may be supplied with a fire extinguishing liquid when the internal temperature equals or rises above a predetermined temperature. Here, the predetermined temperature may be <NUM> or above.

Specifically, the rear cover <NUM> disposed at the rear side of each of the at least two battery packs <NUM> may include a feed port <NUM> through which the fire extinguishing liquid is fed. The feed port <NUM> may be in communication with a refrigerant movement path <NUM>. That is, the feed port <NUM> may be in communication with the refrigerant movement path <NUM> disposed on the left and right sides of the cell assembly <NUM>.

The pack housing <NUM> may receive the cell assembly <NUM> inside, and have an opening <NUM> to through which the outdoor air enters and exits the pack housing <NUM>. For example, as shown in <FIG>, the opening <NUM> may include an inlet <NUM> and an outlet <NUM>. Each of the inlet <NUM> and the outlet <NUM> may be formed in a portion of the pack housing <NUM>. The inlet <NUM> may be configured to allow the outdoor air to be fed into the pack housing <NUM>. The outlet <NUM> may be formed in a portion of the pack housing <NUM> and configured to allow the fed air to exit.

Referring back to <FIG>, the battery rack <NUM> may include a fire extinguishing liquid tank <NUM>, a pipe <NUM> and a fire extinguishing valve <NUM>.

To begin with, the fire extinguishing liquid tank <NUM> may store the fire extinguishing liquid (not shown) therein. For example, the fire extinguishing liquid may be an inorganic salt enriched solution such as potassium carbonate, a chemical foam, an air foam, carbon dioxide or water. The fire extinguishing liquid tank <NUM> may store compressed gas therein to spray the fire extinguishing liquid with proper pressure or move the fire extinguishing liquid along the pipe <NUM>.

For example, the capacity of the fire extinguishing liquid tank <NUM> may be <NUM>, the compressed gas may be <NUM> bar nitrogen, and the fire extinguishing liquid may be <NUM> of water. Here, in case that water is used as the fire extinguishing liquid, water has a cooling and fire extinguishing effect and a heat shielding effect when sprayed into the battery pack <NUM>, so especially when high temperature gas and flames are generated due to thermal runaway, it is effective in preventing thermal propagation. Accordingly, it is possible to effectively prevent the propagation of fires or thermal runaway between the plurality of battery packs <NUM>.

The pipe <NUM> may be connected to supply the fire extinguishing liquid from the fire extinguishing liquid tank <NUM> to each of the at least two battery packs <NUM>. For example, the pipe <NUM> may include a material having resistance to corrosion by water. For example, the pipe <NUM> may include stainless steel. One end of the pipe <NUM> may be connected to an outlet (<NUM> in <FIG>) of the fire extinguishing liquid tank <NUM>. The other end of the pipe <NUM> may be connected to the feed port <NUM> of the pack housing <NUM>.

When gas (air) in the battery pack <NUM> rises above the predetermined temperature, the fire extinguishing valve <NUM> may be configured to supply the fire extinguishing liquid from the fire extinguishing liquid tank <NUM> into the battery pack <NUM>. That is, the fire extinguishing valve <NUM> may be an active valve having an open outlet through which the fire extinguishing liquid is fed into the battery pack <NUM> at the predetermined temperature or above. The active valve may be, for example, a control valve, a pneumatic valve and a solenoid valve with remote control.

<FIG> is a schematic rear perspective view of the internal components of the rack case of the battery rack according to an embodiment of the present disclosure. <FIG> is a schematic diagram of the components of the battery rack according to a first embodiment of the present disclosure.

Referring to <FIG> and <FIG> together with <FIG>, the rack case <NUM> may have a receiving space having two open sides to receive and store each of the plurality of battery packs <NUM>. The plurality of battery packs <NUM> may be vertically arranged in the rack case <NUM>. The plurality of battery packs <NUM> may be vertically arranged in the rack case <NUM>, spaced a predetermined distance apart from one another.

The rack case <NUM> includes a rack plate <NUM> on which the battery pack <NUM> is mounted. Specifically, the rack plate <NUM> includes a mounting surface 312a and an extension portion 312b. More specifically, the mounting surface 312a may have an area that is equivalent to or larger than the lower surface of the battery pack <NUM>. The mounting surface 312a slopes at a predetermined angle relative to a horizontal line P1 such that the height declines as it goes in the sloping direction. That is, the rack plate <NUM> is fixed to other components of the rack case <NUM> with the declining height of the mounting surface 312a as it goes in the sloping direction. For example, as shown in <FIG>, the rack plate <NUM> may be fixed to each of a front frame <NUM> and a rear frame <NUM> of the rack case <NUM> such that the height of the mounting surface 312a declines as it goes rearward. For example, the rack plate <NUM> may slope at <NUM>° to <NUM>° with respect to the horizon.

The extension portion 312b of the upper rack plate <NUM> has an end in the sloping direction extending further outward than the lower battery pack <NUM>. For example, the rack plate <NUM> may include the extension portion 312b at the rear end. For example, the rack plate <NUM> may be configured to allow the fire extinguishing liquid M1 to flow along the slope of the mounting surface 312a and out of the extension portion 312b in the sloping direction.

According to this configuration of the present disclosure, the present disclosure includes the rack case <NUM> having the receiving space to receive the plurality of battery packs <NUM>, and including the plurality of rack plates <NUM> including the mounting surface 312a on which the battery pack <NUM> is mounted, the mounting surface sloping at a predetermined angle with the declining height as it goes in the sloping direction, and the extension portion 312b having an end in the sloping direction extending further outward than the lower battery pack <NUM>, thereby preventing the fire extinguishing liquid M1 supplied to the specific battery pack <NUM> among the plurality of battery packs from flowing into the lower battery pack <NUM> when thermal runaway or a fire occurs in the specific battery pack <NUM>. Accordingly, it is possible to solve the problem caused by the supply of the fire extinguishing liquid M1, that is to say, the remaining battery pack <NUM> except the battery pack <NUM> in which thermal runaway or a fire occurred is wetted with the fire extinguishing liquid M1 and cannot be re-used.

Referring back to <FIG>, the rack case <NUM> may include the front frame <NUM>, the rear frame <NUM> and a fixing bracket <NUM>. The front frame <NUM> may be disposed at the front end of the plurality of battery packs <NUM>. The front frame <NUM> may include a post 314p configured to support the ground.

The rear frame <NUM> may be disposed at the rear end of the plurality of battery packs <NUM>. The rear frame <NUM> may include a post 316p configured to support the ground.

The fixing bracket <NUM> may be coupled to the rack plate <NUM>. That is, the rack plate <NUM> may be coupled to the bottom of the fixing bracket <NUM>. For example, the rack plate <NUM> and the fixing bracket <NUM> may be weld-coupled to each other. The fixing bracket <NUM> may be in the shape of a plate that is bent at approximately <NUM>° in the letter 'L' shape. The fixing bracket <NUM> may extend in the front-rear direction. The front and rear ends of the fixing bracket <NUM> may be bolt-coupled to the front frame <NUM> and the rear frame <NUM> respectively.

The fixing bracket <NUM> may be coupled to the posts 314p, 316p of the front frame <NUM> and the rear frame <NUM>. In this instance, the fixing bracket <NUM> may be fixed to the posts 314p, 316p of the front frame <NUM> and the rear frame <NUM> at a predetermined angle with the declining height as it goes in the sloping direction. For example, as shown in <FIG>, the front end of the fixing bracket <NUM> coupled to the front frame <NUM> may be coupled to the higher location than the rear end of the fixing bracket <NUM> coupled to the rear frame <NUM>.

<FIG> is a schematic diagram of the components of a battery rack according to a second embodiment of the present disclosure.

Referring to <FIG> together with <FIG> and <FIG>, in the battery rack according to another embodiment of the present disclosure, the extended end of the extension portion 312b2 of the lower rack plate 312A among the plurality of rack plates 312A may be disposed on the more inward position than the end of the extension portion 312b1 of the upper rack plate 312A. For example, as shown in <FIG>, the rack plate 312A disposed at the lower location of the rack case <NUM> among the rack plates 312A vertically arranged may have the extension portion 312b1 extending rearward (Y-axis direction) that is shorter than the extension portion 312b2 of the upper rack plate 312A. Accordingly, the extended end of the extension portion 312b2 of the lower rack plate 312A may be disposed on the more inward position than the end of the extension portion 312b1 of the upper rack plate 312A.

The rack case <NUM> may have the extended length of the extension portion of the rack plate 312A that gradually becomes shorter as it goes downward with respect to the extension portion of the rack plate 312A having the topmost battery pack <NUM> mounted thereon. That is, the extended length of the extension portion of the topmost rack plate 312A may be longest, and the extended length of the extension portion of the bottommost rack plate 312A may be shortest.

According to this configuration of the present disclosure, the extended end of the extension portion 312b2 of the lower rack plate 312A among the plurality of rack plates 312A is disposed on the more inward position than the end of the extension portion 312b1 of the upper rack plate 312A, so when the fire extinguishing liquid is supplied, the fire extinguishing liquid moving out of the pack housing <NUM> flows along the slope of the mounting surface 312a of the rack plate 312A and is discharged in the sloping direction through the extension portion 312b1, and in this instance, since the extended length of the extension portion 312b2 disposed at the lower position is shorter than that of the extension portion 312b1 disposed at the higher position, the lower battery pack <NUM> may avoid contamination by the fire extinguishing liquid falling in the direction of gravity from the extension portion 312b1 disposed at the higher position.

<FIG> is a schematic diagram of the components of a battery rack according to a third embodiment of the present disclosure.

Referring to <FIG> together with <FIG> and <FIG>, a plurality of battery packs 200B1, 200B2 and a plurality of rack plates 312B1, 312B2 provided in the battery rack of the third embodiment of the present disclosure may have different positions. The plurality of rack plates 312B1, 312B2 provided in the battery rack of the third embodiment may have the same extended length as opposed to the rack plates 312A of the second embodiment of <FIG>.

Specifically, among the plurality of battery packs 200B1, 200B2, the end in the sloping direction of the lower battery pack 200B2 may be disposed on the more inward position than the end of the upper battery pack 200B1. That is, the extended lengths of the extension portions 312b of the rack plates <NUM> provided in the battery rack of the third embodiment may be the same, but the rack plate <NUM> disposed higher may be spaced a predetermined distance apart toward the front than the lower rack plate <NUM>.

For example, as shown in <FIG>, among the plurality of battery packs <NUM> vertically arranged, the battery pack 200B1 may be disposed at the more front position than the lower battery pack 200B2. That is, the battery rack <NUM> of the present disclosure may have the receiving location of the battery pack <NUM> of the rack case <NUM> disposed at the more front position as the battery pack <NUM> is disposed at the lower position. The location of the extension portion 312b of the rack plate <NUM> may be gradually extended forward as it goes downward.

According to this configuration of the present disclosure, among the plurality of battery packs <NUM>, the end in the sloping direction of the lower battery pack <NUM> is disposed on the more inward position than the end of the upper battery pack <NUM>, so when the fire extinguishing liquid is supplied to the battery pack <NUM>, the fire extinguishing liquid moving out of the pack housing <NUM> does not flow to the lower battery pack <NUM> and may vertically fall by the gravity. That is, the battery pack <NUM> may avoid contamination by the fire extinguishing liquid falling in the direction of gravity from the extension portion 312b disposed at the higher position.

<FIG> is a schematic diagram of the components of a battery rack according to a fourth embodiment of the present disclosure.

Referring to <FIG> together with <FIG> and <FIG>, the battery rack according to the fourth embodiment of the present disclosure may have a stopper 312c to keep the mounted battery pack <NUM> from moving in the sloping direction. For example, the stopper 312c may extend upward from the mounting surface 312a of the rack plate <NUM>. The stopper 312c may be in the shape of a plate that stands upright to support the rear side of the pack housing <NUM> forwards.

According to this configuration of the present disclosure, the rack plate <NUM> includes the stopper 312c to keep the mounted battery pack <NUM> from moving in the sloping direction, thereby preventing the battery pack <NUM> from moving in the sloping direction along the slope of the mounting surface 312a of the rack plate <NUM> and out of the rack case <NUM>. Accordingly, it is possible to increase the safety of the battery rack <NUM> of the present disclosure.

<FIG> is a schematic diagram of the components of a battery rack according to a fifth embodiment of the present disclosure.

Referring to <FIG> together with <FIG> and <FIG>, when comparing the battery rack according to the fifth embodiment of the present disclosure with the battery rack <NUM> according to the first embodiment, the battery pack <NUM> may further include a cover <NUM> on the pack housing <NUM>. The cover <NUM> may be configured to allow the fire extinguishing liquid falling from the upper rack plate <NUM> to flow outward.

The cover <NUM> may be in the shape of a plate having the similar width to the rack plate <NUM>. The cover <NUM> may extend outward from the end of the battery pack <NUM>. For example, as shown in <FIG>, the cover <NUM> extending rearward from the rear end of the battery pack <NUM> may be provided at the rear end of the battery pack <NUM>.

According to this configuration of the present disclosure, the battery rack according to the fifth embodiment of the present disclosure includes the cover <NUM> extending outward from the end of the battery pack <NUM> to allow the fire extinguishing liquid falling from the rack plate <NUM> to flow outward, thereby shielding the fire extinguishing liquid falling from the upper rack plate <NUM>, and preventing the battery pack <NUM> in which thermal runaway or a fire did not occur from being contaminated with the fire extinguishing liquid. Accordingly, it is possible to re-use the battery pack <NUM> in which thermal runaway or a fire did not occur.

<FIG> is a schematic rear perspective view of the components of a battery rack according to a sixth embodiment of the present disclosure.

Referring to <FIG> together with <FIG> and <FIG>, when compared with the battery rack of the first embodiment of <FIG>, the battery rack according to the sixth embodiment of the present disclosure may further include a guide groove <NUM> recessed inward in the rack plate 312C. Specifically, the guide groove <NUM> may be a groove which linearly extends along the mounting surface 312a of the rack plate 312C. When the fire extinguishing liquid is supplied in the event of thermal runaway or a fire in the battery pack <NUM>, the fire extinguishing liquid moving out of the pack housing <NUM> may be allowed to move along the guide groove <NUM> of the rack plate 312C. For example, as shown in <FIG>, the rack plate 312C may be configured such that the fire extinguishing liquid moving out of the pack housing <NUM> moves to the extension portion 312b along the guide groove <NUM> and is discharged through the rear end of the rack plate 312C.

According to this configuration of the present disclosure, the rack plate 312C includes the guide groove <NUM> configured to guide the movement of the fire extinguishing liquid moving out of the pack housing <NUM>, thereby controlling the movement of the fire extinguishing liquid to a specific location of the rack plate 312C, and preventing the fire extinguishing liquid from being fed into the lower battery pack <NUM> due to the unexpected flow of the fire extinguishing liquid. Accordingly, it is possible to prevent the battery pack <NUM> in which thermal runaway or a fire did not occur from being contaminated with the fire extinguishing liquid. The present disclosure can re-use the battery pack <NUM> in which thermal runaway or a fire did not occur.

Referring back to <FIG>, when compared with the battery rack <NUM> of the first embodiment, the battery rack <NUM> according to the sixth embodiment of the present disclosure may include a discharge portion 312p configured to discharge the fire extinguishing liquid falling from the upper battery pack <NUM>. For example, the discharge portion 312p may be in the shape of a conduit having an open top, extending in the upward diagonal direction. When the fire extinguishing liquid falls from the upper rack plate 312C under gravity, the discharge portion 312p may guide the falling fire extinguishing liquid to flow out to one side.

For example, as shown in <FIG>, after the fire extinguishing liquid moving along the guide groove <NUM> formed in the upper rack plate 312C falls from the rear end of the rack plate 312C under gravity, at least a portion of the fire extinguishing liquid may be received in the discharge portion 312p of the lower rack plate 312C, and the received fire extinguishing liquid may move back to the right end along the conduit shape of the discharge portion 312p and may be discharged.

According to this configuration of the present disclosure, the rack plate 312C includes the discharge portion 312p configured to receive the fire extinguishing liquid falling from the upper battery pack <NUM> and flow it out, thereby preventing the lower battery pack <NUM> in which thermal runaway or a fire did not occur from being contaminated with the fire extinguishing liquid. Accordingly, it is possible to re-use the battery pack <NUM> in which thermal runaway or a fire did not occur.

<FIG> is a schematic diagram of the components of a battery rack according to a seventh embodiment of the present disclosure.

Referring to <FIG> together with <FIG> and <FIG>, when compared with the battery rack <NUM> of the first embodiment, the battery rack according to the seventh embodiment of the present disclosure may further include an absorption member <NUM> in the pack housing <NUM> of the battery pack 200D. The absorption member <NUM> may be configured to absorb the fire extinguishing liquid (M1 in <FIG>). The absorption member <NUM> may be a sponge. Alternatively, the absorption member <NUM> may include a super absorbent fiber formed by spinning super absorbent resin into a mesh shape. Here, the super absorbent resin may be configured to absorb the fire extinguishing liquid (water) that is heavier by about <NUM> to <NUM>,<NUM> times than its weight. For example, the super absorbent resin may be a super absorbent resin product from LG Chem. For example, the absorption member <NUM> may be made by simultaneously polymerizing acrylic acid and methyl acrylate as raw materials in water, extracting the resulting polymer and spinning into the shape of a mesh.

The absorption member <NUM> may be interposed between the secondary batteries <NUM> disposed in the opposite direction to the sloping direction among the plurality of secondary batteries <NUM>. For example, as shown in <FIG>, when the rack plate <NUM> slopes rearward (Y-axis direction), the fire extinguishing liquid in the pack housing <NUM> may fill the pack housing <NUM> from the rear part.

Since the battery pack 200D is placed in a rearward incline, the level of the fire extinguishing liquid at the front location in the pack housing <NUM> may be lower than that of the rear location in the pack housing <NUM>. Accordingly, the use of the absorption member <NUM> makes it easy to sufficiently supply the fire extinguishing liquid between the plurality of secondary batteries <NUM>, thereby effectively achieving the cooling or heat shielding of the secondary battery <NUM> disposed at the front location in the pack housing <NUM>.

According to this configuration of the present disclosure, the battery pack 200D may include the absorption member <NUM> between the secondary batteries <NUM> disposed in the opposite direction to the sloping direction among the plurality of secondary batteries <NUM> to absorb the fire extinguishing liquid, thereby distributing the fire extinguishing liquid in the pack housing <NUM> although the battery pack 200D is inclined. Accordingly, when thermal runaway or a fire occurs in the secondary battery <NUM> disposed in the opposite direction to the sloping direction in the pack housing <NUM>, it is possible to effectively suppress the fire or thermal runaway through heat shielding by supplying the fire extinguishing liquid.

<FIG> is a schematic front view of an energy storage system according to an embodiment of the present disclosure.

Referring to <FIG> together with <FIG>, the battery rack <NUM> may further include other components such as a Battery Management System (BMS) <NUM> inside or outside of the rack case <NUM>.

The energy storage system <NUM> according to an embodiment of the present disclosure may include at least two battery racks <NUM>. The at least two battery racks <NUM> may be arranged in a direction. For example, as shown in <FIG>, the energy storage system <NUM> may include three battery racks <NUM> arranged in a direction, each battery rack <NUM> including a rack case <NUM>. Additionally, the energy storage system <NUM> may include a separate BMS <NUM> to control the charge/discharge of each of the three battery racks <NUM>. The energy storage system <NUM> may include a coupling member configured to couple adjacent rack cases <NUM>.

The terms indicating directions as used herein such as upper, lower, left, right, front and rear are used for convenience of description only, and it is obvious to those skilled in the art that the term may change depending on the position of the stated element or an observer.

Claim 1:
A battery rack (<NUM>), comprising:
a plurality of battery packs (<NUM>) vertically arranged, each battery pack (<NUM>) including a plurality of secondary batteries (<NUM>) stacked in a direction, and a pack housing (<NUM>) having an internal space to receive the plurality of secondary batteries (<NUM>) and having a feed port (<NUM>) for supplying a fire extinguishing liquid from a fire extinguishing liquid tank (<NUM>) to said battery pack (<NUM>) when an internal temperature in said battery pack (<NUM>) equals or rises above a predetermined temperature; and
a rack case (<NUM>) having a receiving space to receive the plurality of battery packs (<NUM>),
characterised in that said rack case (<NUM>) includes in said receiving space a plurality of rack plates (<NUM>), each having a mounting surface (312a) on which the battery pack (<NUM>) is mounted, the mounting surface (312a) sloping at a predetermined angle with declining height as it goes in the sloping direction, and an extension portion (312b) having an end in the sloping direction extending further outward than the lower battery pack (<NUM>).