Patent Description:
Meanwhile, when a plurality of battery cells are connected in series or in parallel to configure a battery pack, it is common to configure a battery module including at least one battery cell first, and then configure a battery pack or a battery rack by using at least one battery module and adding other components. The battery pack is generally provided as an energy source of an electric vehicle or the like, and recently, as an energy source for home or industrial use, an energy storage system including a plurality of battery racks is attracting attention.

In the case of a conventional energy storage system, particularly in the case of an energy storage system including a high-temperature battery cell having a management temperature of about <NUM> to <NUM>, it is necessary to construct a suitable thermal management system in a high-temperature region.

In the case of a conventional energy storage system including room-temperature battery cells with a management temperature of about <NUM> to <NUM>, the temperature of a battery cell or an area around the battery cell is managed by using air conditioning equipment for heating and cooling, for example an air conditioner.

However, by using the conventional thermal management system of the energy storage system including room-temperature battery cells, it is difficult to manage an energy storage system including a high-temperature battery cell.

Therefore, even in an energy storage system including high-temperature battery cells, it is required to find a way to more effectively manage the temperature of the battery cell or the area around the battery cell.

<CIT> concerns a system for managing the temperature of a battery. The system includes a battery configured for storing electrical energy and a water-cooling system including a flow path through which cooling water flows. The battery is provided on the flow path. The water-cooling system further comprises a reservoir tank for storing cooling water. In the water-cooling system, cooling water is circulated on the path. A water pump is provided between the reservoir tank and the battery for circulating cooling water on the path.

<CIT> concerns a heat pump system for a vehicle. The heat pump system includes a battery cooling line that is connected with a battery module and in which coolant moves; a chiller that is connected with the battery cooling line through a first connection line to adjust a temperature of coolant by selectively exchanging a heat of a refrigerant and coolant injected therein and that is connected with a refrigerant line of an air-conditioner device through a second connection line; an electric unit device cooler including a radiator and a first water pump that are connected through a cooling line to circulate coolant for cooling a motor and an electronic unit and that is selectively connectable with the battery cooling line and the first connection line through a first valve; and a bypass line selectively connecting the second connection line and the refrigerant line through a second valve provided in the refrigerant line.

<CIT> concerns a battery system, battery module, and method for cooling the battery module.

The present disclosure is designed to solve the problems of the related art, and therefore the present disclosure is directed to providing an energy storage system, which may more efficiently manage the temperature of a battery cell or an area around the battery cell.

In addition, the present disclosure is also directed to providing an energy storage system, which may maintain an appropriate temperature of the battery cell according to the management temperature of the battery cell.

In one aspect of the present invention, there is provided an energy storage system as defined in claim <NUM>, comprising: a battery rack including at least one battery cell and having a cooling channel for cooling the at least one battery cell; a coolant tank spaced apart from the battery rack by a predetermined distance and having a predetermined coolant; a pipe unit configured to connect the coolant tank and the battery rack and configured to circulate the coolant between the battery rack and the coolant tank; and a pump unit connected to the pipe unit, disposed between the coolant tank and the battery rack, and configured to adjust the supply of the coolant to the battery rack.

The energy storage system further comprises a diverging valve connected to the pipe unit, a first heat exchanger disposed between the battery rack and the diverging valve; and a second heat exchanger spaced apart from the first heat exchanger by a predetermined distance and disposed between the diverging valve and the coolant tank. The energy storage system is configured to perform additional cooling through the second heat exchanger by controlling the diverging valve according to the temperature of the coolant that has passed through the battery rack and the first heat exchanger.

The battery rack may include an inlet port into which the coolant is introduced, the inlet port being configured to communicate with the cooling channel; and an outlet port spaced apart from the inlet port by a predetermined distance and configured to communicate with the cooling channel, the coolant tank may include a coolant outlet port configured to discharge the coolant toward the battery rack; and at least one coolant inlet port spaced apart from the coolant outlet port and configured such that the coolant discharged from the battery rack is introduced thereto, and the pump unit may be disposed between the inlet port of the battery rack and the coolant outlet port of the coolant tank.

The energy storage system may further comprise an opening/closing valve connected to the pipe unit and provided between the pump unit and the coolant outlet port of the coolant tank.

The energy storage system may further comprise the diverging valve provided between the at least one heat exchange unit and the coolant tank.

The energy storage system may further comprise at least one fan unit configured to cool the at least one heat exchange unit.

The battery rack may include at least one rack temperature sensor configured to detect a temperature of the at least one battery cell.

The battery rack may include a fire sensor configured to detect a fire of the at least one battery cell.

The coolant tank may include a heater unit configured to raise a temperature of the coolant.

According to various embodiments as above, it is possible to provide an energy storage system, which may more efficiently manage the temperature of a battery cell or an area around the battery cell.

In addition, according to various embodiments as above, it is possible to provide an energy storage system, which may maintain an appropriate temperature of the battery cell according to the management temperature of the battery cell.

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

Referring to <FIG>, the energy storage system <NUM> includes a battery rack <NUM>, a coolant tank <NUM>, a pipe unit <NUM>, and a pump unit <NUM>.

The battery rack <NUM> includes at least one battery cell <NUM> (see <FIG>), and includes a cooling channel <NUM> (see <FIG>) for cooling the at least one battery cell <NUM>.

Hereinafter, the battery rack <NUM> will be described in more detail with reference to <FIG>.

<FIG> is a diagram for illustrating a battery rack of the energy storage system according to an embodiment of the present disclosure.

Referring to <FIG>, the battery rack <NUM> may include a battery cell <NUM>, a rack case <NUM>, a cooling channel <NUM>, a rack temperature sensor <NUM>, a fire sensor <NUM>, and a control unit <NUM>.

The battery cell <NUM> is a secondary battery, and may be provided as a pouch-type secondary battery, a rectangular secondary battery, or a cylindrical secondary battery. Hereinafter, in this embodiment, the battery cell <NUM> will be described as a pouch-type secondary battery.

At least one battery cell <NUM> or a plurality of battery cells <NUM> may be provided. Hereinafter, in this embodiment, it will be described that a plurality of battery cells <NUM> are provided.

The plurality of battery cells <NUM> may be provided as high-temperature battery cells. The high-temperature battery cell generally has a management temperature of <NUM> to <NUM>, which may mean optimal battery cells in terms of battery performance and lifespan in a high-temperature region to which the management temperature belongs. If the battery rack <NUM> includes a plurality of battery cells <NUM>, the battery rack <NUM> may be used, for example, in a tropical climate region.

The rack case <NUM> may accommodate the plurality of battery cells <NUM>, the cooling channel <NUM>, the rack temperature sensor <NUM>, the fire sensor <NUM>, the control unit, and various electrical components of the battery rack <NUM>.

To this end, the rack case <NUM> may have an accommodation space capable of accommodating the plurality of battery cells <NUM>, the cooling channel <NUM>, the rack temperature sensor <NUM>, the fire sensor <NUM>, the control unit, and various electrical components of the battery rack <NUM>.

The rack case <NUM> may include a case body <NUM>, an inlet port <NUM>, and an outlet port <NUM>.

The case body <NUM> may have an inner space of a predetermined size so that the accommodation space may be provided. The plurality of battery cells <NUM>, the cooling channel <NUM>, the rack temperature sensor <NUM>, the fire sensor <NUM>, the control unit, and various electric components of the battery rack <NUM> may be accommodated in the case body <NUM>.

A coolant <NUM> of the coolant tank <NUM>, explained later, is introduced through the inlet port <NUM>, and the inlet port <NUM> may be formed at one side of the case body <NUM>. The inlet port <NUM> may communicate with the cooling channel <NUM>, explained later.

The outlet port <NUM> is formed at the other side of the case body <NUM>, and may be disposed to be spaced apart from the inlet port <NUM> by a predetermined distance. The outlet port <NUM> communicates with the cooling channel <NUM>, explained later, and the coolant <NUM> that has passed through the cooling channel <NUM>, explained later, may be discharged out of the case body <NUM> through the outlet port <NUM>.

The cooling channel <NUM> is provided to the case body <NUM>, and may communicate with the inlet port <NUM> and the outlet port <NUM>. The cooling channel <NUM> may cool the plurality of battery cells <NUM>. For this, the coolant <NUM>, explained later, may pass through the cooling channel <NUM>.

The rack temperature sensor <NUM> is provided inside the case body <NUM>, and may detect or measure a temperature of at least one of the plurality of battery cells <NUM> in the case body <NUM>.

The fire sensor <NUM> is provided inside the case body <NUM>, and may detect an abnormal condition or the like of the plurality of battery cells <NUM> in the case body <NUM>. For example, when a fire situation in the plurality of battery cells <NUM> occurs, the fire sensor <NUM> may detect a fire in the at least one or more plurality of battery cells <NUM>. Specifically, the fire sensor <NUM> may detect a flame or smoke generated at the battery cells <NUM>.

The control unit <NUM> is for managing and controlling the battery rack <NUM>, and may be electrically connected to the plurality of battery cells <NUM>, the rack temperature sensor <NUM>, and the fire sensor <NUM>.

The control unit <NUM> may be provided to be electrically connected to the coolant tank <NUM>, the pump unit <NUM>, a heat exchange unit <NUM>, a diverging valve <NUM>, a fan unit <NUM>, and a temperature sensor <NUM>, explained later, provided outside the battery rack <NUM>.

The detailed operation of the control unit <NUM> will be described in more detail below.

The coolant tank <NUM> is spaced apart from the battery rack <NUM> by a predetermined distance, and has a predetermined coolant <NUM>.

Hereinafter, the coolant tank <NUM> will be described in more detail with reference to <FIG> and <FIG>.

<FIG> and <FIG> are diagrams for illustrating a coolant tank according to various embodiments of the energy storage system according to an embodiment of the present disclosure.

Referring to <FIG>, the coolant tank <NUM> may include a tank body <NUM>, a coolant <NUM>, a coolant outlet port <NUM>, and a coolant inlet port <NUM>.

The tank body <NUM> may accommodate the coolant <NUM>. For this, an accommodation space capable of accommodating the coolant <NUM> may be provided in the tank body <NUM>.

The coolant <NUM> may be provided as a cooling fluid capable of cooling the plurality of battery cells <NUM> of the battery rack <NUM>. In this embodiment, it will be described that the coolant <NUM> is water.

The coolant outlet port <NUM> is for discharging the coolant <NUM> toward the battery rack <NUM>, and may be provided to the tank body <NUM> to communicate with the inner space of the tank body <NUM>.

The coolant outlet port <NUM> communicates with a first pipe <NUM> of the pipe unit <NUM>, explained later, and may discharge the coolant <NUM> inside the tank body <NUM> toward the first pipe <NUM> of the pipe unit <NUM>, explained later.

The coolant inlet port <NUM> is spaced apart from the coolant outlet port <NUM>, and the coolant <NUM> discharged from the battery rack <NUM> may be introduced through the coolant inlet port <NUM>. The coolant inlet port <NUM> may be provided to the tank body <NUM> to communicate with the inner space of the tank body <NUM>.

The coolant inlet port <NUM> may include a first inlet port <NUM> and a second inlet port <NUM>.

The first inlet port <NUM> may be provided to the tank body <NUM> to communicate with a third pipe <NUM> of the pipe unit <NUM>, explained later, and communicate with the inner space of the tank body <NUM>. The first inlet port <NUM> may guide the coolant <NUM> sent from the third pipe <NUM> side of the pipe unit <NUM>, explained later, into the tank body <NUM>.

The second inlet port <NUM> may be provided to the tank body <NUM> to communicate with a fourth pipe <NUM> of a pipe unit <NUM>, explained, and communicate with the inner space of the tank body <NUM>. The second inlet port <NUM> may guide the coolant <NUM> sent from the fourth pipe <NUM> of the pipe unit <NUM>, explained later, into the tank body <NUM>.

Referring to <FIG>, the coolant tank <NUM> may further include a heater unit <NUM>.

The heater unit <NUM> is mounted to the tank body <NUM> of the coolant tank <NUM>, and may heat the coolant <NUM> inside the tank body <NUM> to raise the temperature of the coolant <NUM>. Meanwhile, a third temperature sensor <NUM> of the temperature sensor unit <NUM>, explained later, for detecting or measuring the temperature of the coolant <NUM> inside the tank body <NUM> may be provided inside the tank body <NUM> of the coolant tank <NUM>.

The operation of the heater unit <NUM> will be described in more detail with reference to of <FIG>.

Referring to <FIG> again, the pipe unit <NUM> is for circulating the coolant <NUM> between the battery rack <NUM> and the coolant tank <NUM>, and connects the coolant tank <NUM> and the battery rack <NUM>.

The pipe unit <NUM> may include a first pipe <NUM>, a second pipe <NUM>, a third pipe <NUM>, and a fourth pipe <NUM>.

The first pipe <NUM> may connect the battery rack <NUM> and the coolant tank <NUM>. The pump unit <NUM> and an opening/closing valve <NUM>, explained later, may be connected to the first pipe <NUM>.

The second pipe <NUM> may connect the battery rack <NUM> and a first heat exchanger <NUM> of the heat exchange unit <NUM>, explained later.

The third pipe <NUM> may connect the first heat exchanger <NUM> of the heat exchange unit <NUM>, explained later, and the coolant tank <NUM>. Specifically, the third pipe <NUM> may be connected to the first inlet port <NUM> of the coolant inlet port <NUM> of the coolant tank <NUM>. A diverging valve <NUM>, explained later, and the first temperature sensor <NUM> of the temperature sensor unit <NUM>, explained later, may be connected to the third pipe <NUM>.

The fourth pipe <NUM> may connect the diverging valve <NUM>, explained later, and the coolant tank <NUM>. Specifically, the fourth pipe <NUM> may be connected to the second inlet port <NUM> of the coolant inlet port <NUM> of the coolant tank <NUM>. A second heat exchanger <NUM> of the heat exchange unit <NUM>, explained later, and a second temperature sensor <NUM> of the temperature sensor unit <NUM>, explained later, may be connected to the fourth pipe <NUM>.

The pump unit <NUM> is to control the supply of the coolant <NUM> toward the battery rack <NUM>, is connected to the pipe unit <NUM>, and is disposed between the coolant tank <NUM> and the battery rack <NUM>.

The pump unit <NUM> may be disposed between the inlet port <NUM> of the battery rack <NUM> and the coolant outlet port <NUM> of the coolant tank <NUM>.

More specifically, the pump unit <NUM> is connected to the first pipe <NUM> of the pipe unit <NUM>, and may be disposed between the opening/closing valve <NUM> and the battery rack <NUM>.

Meanwhile, the energy storage system <NUM> may further include an opening/closing valve <NUM>, a heat exchange unit <NUM>, and a diverging valve <NUM>.

The opening/closing valve <NUM> may decide whether to supply the coolant <NUM> of the coolant tank <NUM> to the battery rack <NUM> or stop the supply of the coolant <NUM> to the battery rack <NUM> through manual or automatic turning-on/off operation by user manipulation or the like.

The opening/closing valve <NUM> is connected to the pipe unit <NUM>, and may be provided between the pump unit <NUM> and the coolant outlet port <NUM> of the coolant tank <NUM>.

The heat exchange unit <NUM> is to manage the temperature of the coolant <NUM> that has passed through the battery rack <NUM>, and may be disposed between the outlet port <NUM> of the battery rack <NUM> and the at least one coolant inlet port <NUM> of the coolant tank <NUM>. The heat exchange unit <NUM> may be provided by at least one or in plurality. Hereinafter, in this embodiment, it will be described that the heat exchange unit <NUM> is provided in plurality.

The plurality of heat exchange units <NUM> includes a first heat exchanger <NUM> and a second heat exchanger <NUM>.

The first heat exchanger <NUM> is disposed between the battery rack <NUM> and the diverging valve <NUM>. Specifically, the first heat exchanger <NUM> may guide the cooling of the coolant <NUM> delivered through the second pipe <NUM> of the pipe unit <NUM>. This first heat exchanger <NUM> may be provided as a radiator.

The second heat exchanger <NUM> is spaced apart from the first heat exchanger <NUM> by a predetermined distance, and is disposed between the diverging valve <NUM> and the coolant tank <NUM>. Specifically, the second heat exchanger <NUM> may guide the cooling of the coolant <NUM> delivered through the fourth pipe <NUM> of the pipe unit <NUM>. This second heat exchanger <NUM> may be provided as a radiator.

The diverging valve <NUM> is connected to the pipe unit <NUM>, and may be provided between the at least one heat exchange unit <NUM> and the coolant tank <NUM>.

The diverging valve <NUM> will be described in more detail with reference to <FIG> below.

<FIG> is a diagram for illustrating a diverging valve of the energy storage system according to an embodiment of the present disclosure.

Referring to <FIG>, the diverging valve <NUM> may include an inlet portion <NUM>, an outlet portion <NUM>, and a second diverging portion <NUM>.

The inlet portion <NUM> may be provided at one side of the diverging valve <NUM>. The coolant <NUM> (see <FIG>) that has passed through the first heat exchanger <NUM> (see <FIG>) of the heat exchange unit <NUM> (see <FIG>) may be introduced into the inlet portion <NUM>.

The outlet portion <NUM> operates to be opened and closed, and may send the coolant <NUM> (see <FIG>) introduced from the inlet portion <NUM> to the third pipe <NUM> of the pipe unit <NUM> (see <FIG>). The coolant <NUM> (see <FIG>) discharged through the outlet portion <NUM> may be re-introduced into the coolant tank <NUM> through the third pipe <NUM>.

The diverging portion <NUM> may be opened and closed, and may be provided between the inlet portion <NUM> and the outlet portion <NUM>. The diverging portion <NUM> may send the coolant <NUM> (see <FIG>) introduced from the inlet portion <NUM> to the fourth pipe <NUM> of the pipe unit <NUM> (see <FIG>). The coolant (<NUM>, see <FIG>) discharged through the diverging portion <NUM> may be re-introduced into the coolant tank <NUM> through the fourth pipe <NUM>.

Referring to <FIG> again, the energy storage system <NUM> may further include a fan unit <NUM> and a temperature sensor <NUM>.

The fan unit <NUM> is for cooling the at least one heat exchange unit <NUM> and may be provided in a number corresponding to the number of the at least one heat exchange unit <NUM>.

The fan unit <NUM> may include a first blowing fan <NUM> and a second blowing fan <NUM>.

The first blowing fan <NUM> may be disposed near the first heat exchanger <NUM> of the heat exchange unit <NUM>. The first blowing fan <NUM> may include a cooling fan. The first blowing fan <NUM> may send out a cooling air to the first heat exchanger <NUM>, and may appropriately change the cooling capacity as needed by adjusting the rotation speed (RPM) of the cooling fan.

The second blowing fan <NUM> may be disposed near the second heat exchanger <NUM> of the heat exchange unit <NUM>. The second blowing fan <NUM> may include a cooling fan. The first blowing fan <NUM> may send out a cooling air to the second heat exchanger <NUM>, and may appropriately change the cooling capacity as needed by adjusting the rotation speed (RPM) of the cooling fan.

The temperature sensor unit <NUM> is for measuring or sensing temperature, and may be provided at a specific point or a specific component of the energy storage system <NUM>.

The temperature sensor unit <NUM> may be provided by at least one or in plurality. Hereinafter, in this embodiment, it will be described that the temperature sensor <NUM> is provided in plurality.

The plurality of temperature sensor units <NUM> may include a first temperature sensor <NUM>, a second temperature sensor <NUM>, and a third temperature sensor <NUM>.

The first temperature sensor <NUM> is provided in the third pipe <NUM> of the pipe unit <NUM>, and may be disposed between the first heat exchanger <NUM> of the heat exchange unit <NUM> and the diverging valve <NUM>. The first temperature sensor <NUM> may detect or measure the temperature of the coolant <NUM> that has passed the first heat exchanger <NUM> of the heat exchange unit <NUM>.

The second temperature sensor <NUM> is provided in the fourth pipe <NUM> of the pipe unit <NUM>, and may be disposed between the second heat exchanger <NUM> of the heat exchange unit <NUM> and the coolant tank <NUM>. The second temperature sensor <NUM> may detect or measure the temperature of the coolant <NUM> that has passed through the second heat exchanger <NUM> of the heat exchange unit <NUM>.

The third temperature sensor <NUM> may be provided inside the tank body <NUM> of the coolant tank <NUM>. The third temperature sensor <NUM> may sense or measure the temperature of the coolant <NUM> in the tank body <NUM>.

Hereinafter, the cooling mechanism of the energy storage system <NUM> according to this embodiment will be described in more detail.

<FIG> and <FIG> are diagrams for illustrating a cooling mechanism of the energy storage system according to an embodiment of the present disclosure.

Referring to <FIG>, the control unit <NUM> of the battery rack <NUM> of the energy storage system <NUM> may control the temperature of the plurality of battery cells <NUM> of the battery rack <NUM> to be maintained in a preset temperature range.

The control unit <NUM> may control the opening/closing valve <NUM> to move the coolant <NUM> of the coolant tank <NUM> to the battery rack <NUM>. When the opening/closing valve <NUM> is opened, the coolant <NUM>, C1 may move from the coolant tank <NUM> to the battery rack <NUM>. Here, the control unit <NUM> may control the pump unit <NUM> to control the supply amount or supply speed of the coolant <NUM>, C1.

The coolant <NUM>, C1 may be guided to exit the coolant tank <NUM> and pass the cooling channel <NUM> of the battery rack <NUM> through the first pipe <NUM> of the pipe unit <NUM> to cool the plurality of battery cells <NUM> in the battery rack <NUM>, or to maintain the temperature of the plurality of battery cells <NUM> at a preset temperature.

The control unit <NUM> may adjust the supply amount, the supply rate, or the like of the coolant <NUM> passing through the cooling channel <NUM>, through the temperature information obtained through the rack temperature sensor <NUM>, so that the battery cells <NUM> may be maintained in a preset temperature range.

For example, the control unit <NUM> may increase the supply amount or the supply rate of the coolant <NUM> passing through the cooling channel <NUM> when the battery cells <NUM> are overheated.

In addition, if an abnormal situation such as a flame situation of the battery cells <NUM> occurs, when a flame or smoke is detected from the fire sensor <NUM>, the control unit <NUM> may increase the supply amount or the supply rate of the coolant <NUM> passing through the cooling channel <NUM> further.

The coolant <NUM>, C2 that have passed through the cooling channel <NUM> of the battery rack <NUM> may move to the first heat exchanger <NUM> of the heat exchange unit <NUM> through the second pipe <NUM> of the pipe unit <NUM>. Here, the coolant <NUM>, C2 after passing through the cooling channel <NUM> of the battery rack <NUM> may have a higher temperature than the coolant <NUM>, C1 before passing through the cooling channel <NUM>.

The control unit <NUM> may drive the first blowing fan <NUM> of the fan unit <NUM> to lower the temperature of the coolant <NUM>, C2 that have passed through the cooling channel <NUM> of the battery rack <NUM>, when the coolant <NUM>, C2 passes through the first heat exchanger <NUM> of the heat exchange unit <NUM>.

Here, the first blowing fan <NUM> of the fan unit <NUM> may be electrically connected to the control unit <NUM>, the rack temperature sensor <NUM>, and the temperature sensor unit <NUM>. The control unit <NUM> may adjust the cooling amount of the coolant <NUM>, C2 by changing the fan rotation amount of the first blowing fan <NUM> according to the temperature information of the rack temperature sensor <NUM> and the temperature sensor unit <NUM>.

If the coolant <NUM>, C3 that has passed the first heat exchanger <NUM> is lower than a preset temperature, the control unit <NUM> may open the inlet portion <NUM> and the outlet portion <NUM> of the diverging valve <NUM> and close the diverging portion <NUM> of the diverging valve <NUM>.

Accordingly, the coolant <NUM>, C3 that have passed through the first heat exchanger <NUM> may be re-introduced into the coolant tank <NUM> through the inlet portion <NUM> and the outlet portion <NUM> of the diverging valve <NUM>. Here, the coolant <NUM>, C3 after passing through the first heat exchanger <NUM> may have a lower temperature than the coolant <NUM>, C2 before passing through the first heat exchanger <NUM>.

The coolant <NUM> re-introduced into the coolant tank <NUM> may circulate along the pipe unit <NUM> according to the control of the control unit <NUM> or the like until the temperature of the battery cells <NUM> in the battery rack <NUM> meets a preset temperature range.

Meanwhile, in the energy storage system <NUM>, the coolant <NUM>, C3 that has passed the first heat exchanger <NUM> may be higher than the preset temperature.

Referring to <FIG>, when the coolant <NUM>, C3 that has passed through the first heat exchanger <NUM> is higher than the preset temperature, the control unit <NUM> may open the inlet portion <NUM> and the diverging portion <NUM> of the diverging valve <NUM> and close the outlet portion <NUM> of the diverging valve <NUM> through the first temperature sensor <NUM>.

Accordingly, the coolant <NUM>, C3 that has passed through the first heat exchanger <NUM> may pass through the second heat exchanger <NUM> of the heat exchange unit <NUM> via the inlet portion <NUM> and the diverging portion <NUM> of the diverging valve <NUM>.

The control unit <NUM> may drive the second blowing fan <NUM> of the fan unit <NUM> to lower the temperature of the coolant <NUM>, C4 emitting from the diverging portion <NUM> of the diverging valve <NUM>, when the coolant <NUM>, C4 passes through the second heat exchanger <NUM> of the heat exchange unit <NUM>.

Here, the second blowing fan <NUM> of the fan unit <NUM> may be electrically connected to the control unit <NUM>, the rack temperature sensor <NUM>, and the temperature sensor unit <NUM>. The control unit <NUM> may change the fan rotation amount of the second blowing fan <NUM>, like the first blowing fan <NUM>, according to the temperature information of the rack temperature sensor <NUM> and the temperature sensor unit <NUM> to adjust the cooling amount of the coolant <NUM>, C4.

As such, in this embodiment, when the coolant <NUM>, C3 that has passed through the first heat exchanger <NUM> is higher than the preset temperature, in the energy storage system <NUM>, the coolant <NUM>, C3 may be diverged to the second heat exchanger <NUM> through the diverging portion <NUM> of the diverging valve <NUM> to additionally cool the coolant <NUM>, C4 or additionally control the temperature of the coolant <NUM>, C4 through the second heat exchanger <NUM> and the second blowing fan <NUM>.

The coolant <NUM> and C4 that have passed through the second heat exchanger <NUM> may be re-introduced into the coolant tank <NUM> through the fourth pipe <NUM> of the pipe unit <NUM>. Here, the coolant <NUM>, C4 passing through the second heat exchanger <NUM> may have a lower temperature than the coolant <NUM>, C3 passing through the first heat exchanger <NUM>.

The coolant <NUM> re-introduced into the coolant tank <NUM> may circulate along the pipe unit <NUM> according to the control of the control unit <NUM> until the temperature of the battery cells <NUM> in the battery rack <NUM> meets the preset temperature range.

As such, the energy storage system <NUM> according to this embodiment in accordance with the claimed invention appropriately performs additional cooling through the second heat exchanger <NUM> by controlling the diverging valve <NUM> according to the temperature of the coolant <NUM> that has passed through the battery rack <NUM> and the first heat exchanger <NUM>.

That is, if the temperature of the coolant <NUM> is sufficiently lower than the preset temperature range, the coolant <NUM> is directly moved to the coolant tank <NUM> without passing through the second heat exchanger <NUM>, and only when the temperature of the coolant <NUM> is higher than the preset temperature range, additional cooling may be performed through the second heat exchanger <NUM>.

Accordingly, in this embodiment, through the diverging valve <NUM>, the second heat exchanger <NUM> and the second blowing fan <NUM> are selectively driven, so that the efficiency of the entire cooling system may be significantly increased.

Hereinafter, the flow chart about the cooling mechanism according to the flow of the coolant <NUM> after passing through the first heat exchanger <NUM> of the energy storage system <NUM> according to this embodiment will be described.

<FIG> is a flowchart for illustrating the cooling mechanism of the energy storage system according to an embodiment of the present disclosure.

Referring to <FIG>, first, a coolant may be cooled through the first heat exchanger (S10). Thereafter, the control unit may compare the temperature of the coolant measured through the first temperature sensor with a preset coolant temperature (S20). If the temperature of the coolant measured through the first temperature sensor is lower than the preset coolant temperature, the control unit may open the outlet portion of the diverging valve (S21).

Accordingly, the coolant may flow to the third pipe of the pipe unit (S23) and may be introduced into the coolant tank (S30).

If the temperature of the coolant measured through the first temperature sensor is equal to or higher than the preset coolant temperature, the control unit may open the diverging portion of the diverging valve (S25).

Accordingly, the coolant may flow to the fourth pipe of the pipe unit (S27), may be further cooled through the second heat exchanger (S29), and then may be introduced into the coolant tank (S30).

As such, the energy storage system <NUM> according to this embodiment may perform selective additional cooling of the coolant <NUM> according to the temperature of the coolant <NUM>, through the diverging valve <NUM> and the second heat exchanger <NUM>, and thus it is possible to maximize cooling efficiency or temperature management efficiency.

<FIG> is a diagram for illustrating a coolant tank heating mechanism of the energy storage system according to an embodiment of the present disclosure.

Referring to <FIG>, in the case of the coolant <NUM> inside the coolant tank <NUM>, when the outside temperature is low, such as in winter, the coolant <NUM> inside the tank body <NUM> of the coolant tank <NUM> may be supercooled or frozen.

At this time, the control unit <NUM> (see <FIG>) operates the heater unit <NUM> when the temperature of the coolant <NUM> inside the tank body <NUM> of the coolant tank <NUM> measured through the third temperature sensor <NUM> is lower than the preset temperature. The heater unit <NUM> may heat the coolant <NUM> inside the tank body <NUM> of the coolant tank <NUM> until it reaches the preset temperature.

On the other hand, the control unit <NUM> (see <FIG>) may operate the opening/closing valve <NUM>, the pump unit <NUM>, or the like to circulate the coolant heated to the predetermined temperature when the outdoor temperature such as in winter is low as described above. According to the circulation of the coolant heated to the predetermined temperature, freezing or the like of the pipe unit <NUM> may be prevented.

According to various embodiments as described above, it is possible to provide the energy storage system <NUM> capable of more efficiently managing the temperature of the battery cell <NUM> or the area surrounding the battery cell <NUM>.

In addition, according to various embodiments as described above, it is possible to provide an energy storage system <NUM> capable of maintaining an appropriate temperature of the battery cell <NUM> according to the management temperature of the battery cell <NUM>.

Claim 1:
An energy storage system (<NUM>), comprising:
a battery rack (<NUM>) including at least one battery cell (<NUM>) and having a cooling channel (<NUM>) for cooling the at least one battery cell (<NUM>);
a coolant tank (<NUM>) spaced apart from the battery rack (<NUM>) by a predetermined distance and having a predetermined coolant (<NUM>);
a pipe unit (<NUM>) configured to connect the coolant tank (<NUM>) and the battery rack (<NUM>) and configured to circulate the coolant (<NUM>) between the battery rack (<NUM>) and the coolant tank (<NUM>); and
a pump unit (<NUM>) connected to the pipe unit (<NUM>), disposed between the coolant tank (<NUM>) and the battery rack (<NUM>), and configured to adjust the supply of the coolant (<NUM>) to the battery rack (<NUM>),
wherein the energy storage system (<NUM>) further comprises:
a diverging valve (<NUM>) connected to the pipe unit (<NUM>),
a first heat exchanger (<NUM>) disposed between the battery rack (<NUM>) and the diverging valve (<NUM>); and
a second heat exchanger (<NUM>) spaced apart from the first heat exchanger (<NUM>) by a predetermined distance and disposed between the diverging valve (<NUM>) and the coolant tank (<NUM>),
characterized in that the energy storage system (<NUM>) is configured to perform additional cooling through the second heat exchanger (<NUM>) by controlling the diverging valve (<NUM>) according to the temperature of the coolant (<NUM>) that has passed through the battery rack (<NUM>) and the first heat exchanger (<NUM>).