Patent Description:
The present invention relates to a pouch-type battery cell including a venting member and a battery pack including the same. Specifically, the present invention relates to a pouch-type battery cell and , and a battery pack including the same, the pouch-type battery cell capable of inducing the venting of a battery cell by adding a venting member made of a shape memory alloy material on an outer surface of the pouch-type battery cell, or an inner surface of an battery pack case including the pouch-type battery cell.

As an energy source capable of repeatedly charging and discharging portable electronic products such as mobile phones, tablet PCs, and vacuum cleaners, the demand for secondary batteries is rapidly increasing. Research and development of secondary batteries for application to devices requiring high capacity and high efficiency, such as electric vehicles and power storage devices, are in progress.

In particular, among secondary batteries, lithium secondary batteries having advantages such as high energy density, high voltage, high power, and excellent life characteristics are widely used.

The lithium secondary batteries may be classified based on the shape of a case. For example, there is a cylindrical battery or a prismatic battery, each of the cylindrical battery and the prismatic battery is configured to have an electrode assembly mounted in a metal can, and there is a pouch-type battery, the pouch-type battery is configured to have an electrode assembly mounted in a pouch-type case made of an aluminum laminate sheet. The pouch-type battery has an advantage that it can freely change in shape because it can be easily curved or bent.

In general, a lithium secondary battery includes an electrode active material, a binder, and an electrolyte constituting an electrode as main components, which are electrochemically stable at operating voltages ranging from <NUM>. 5V to <NUM>. However, when the voltage of the lithium secondary battery rises above the operating voltage, the components are decomposed to generate gas, and thus the lithium secondary battery is expanded and deformed due to the generated gas. In addition, when a separator is damaged by an inorganic material included in the electrode mixture, contact between a positive electrode and a negative electrode may cause a large amount of current to flow and promote the generation of heat and gas, which may cause ignition and explosion of the secondary battery.

In order to remove the gas generated inside the battery, the cylindrical battery and the prismatic battery are provided with a safety device such as a vent in a cap assembly, while the pouch-type battery only determines venting by the sealing strength without a separate safety device. However, there is a problem that it is difficult to guide venting under desired conditions.

In this regard, Patent Document <NUM> discloses a secondary battery in which an opening communicating with an interior is formed in a battery case and a safety opening and closing portion of a shape memory alloy capable of opening and closing the opening is added.

Patent Document <NUM> uses a structure for opening and closing the opening in a pouch case of the state in which the opening was formed. However, since the safety opening and closing portion is applied to a sealing part of the pouch battery, there is a problem that a dead space occurs in the width direction of the battery cell because a structure in which the sealing part is bent is not applicable.

Patent Document <NUM> relates to a secondary battery having a form of opening through a pouch while a bentshape of shape memory alloy is being unbent when the temperature rises.

However, Patent Document <NUM> is not preferable because the shape memory alloy is located inside the pouch-type battery, and there is a problem that the shape memory alloy generates side reactions with the electrolyte and the like.

As such, in order to discharge the gas generated inside the pouch-type battery cell at a desired temperature, there is an urgent need for a technology that can set the discharge temperature of the gas and can prevent the ignition and explosion caused by the increased internal pressure of the secondary battery.

<CIT> relates to a galvanic cell having a releasable connecting area.

<CIT> relates to a secondary battery comprising a case adapted to receive an electrode assembly and a safety unit adapted to punch the case.

<CIT> relates to an electrical storage device and an electrical storage module having an internal pressure releasing mechanism.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide a pouch-type battery cell as described in the appended independent claim, which is capable of discharging gas in the battery cell at a desired temperature by applying a venting member made of a shape memory alloy on an outer surface of the pouch-type battery cell.

The subject matter of the present invention is defined in the appended claims. In accordance with the present invention, the above and other objects can be accomplished by the provision of a pouch-type battery cell as described in the appended claims. In accordance with the present disclosure, a pouch-type battery cell comprises a battery case including a metal layer and a polymer resin layer, wherein the battery case may include an electrode assembly receiving part formed on at least one of an upper case and a lower case, and a venting member disposed on an outer surface of the electrode assembly receiving part, which is an adjacent portion of a sealing part of the battery case, the venting member made of a shape memory alloy that is deformed to penetrate the battery case when the temperature of the battery cell increases.

The venting member may be formed in a straight shape at a normal temperature, and at least one end thereof may be bent when the temperature increases.

A deformed portion of the venting member may have a pointed end.

The battery case may be configured to have a structure in which the electrode assembly receiving part is formed in the upper case and the lower case, respectively; the electrode assembly may be a unidirectional electrode assembly in which electrode terminals are formed in one direction; and the venting member may be disposed on the outer surface of the electrode assembly receiving part, which is an adjacent portion of the sealing part where the electrode terminals are disposed.

The battery case may be configured to have a structure in which the electrode assembly receiving part is formed in the upper case and the lower case, respectively; the electrode assembly may be a bidirectional electrode assembly in which electrode terminals are formed in both directions; and the venting member may be disposed on an outer surface of the electrode assembly receiving part of at least one of the upper case and the lower case, which is an adjacent portion of the sealing part where the electrode terminals are disposed or an adjacent portion of the sealing part where the electrode terminals are not disposed.

The venting member may be disposed on the outer surface of the electrode assembly receiving part in a direction in which the electrode terminal is not disposed among side surfaces of the electrode assembly receiving part.

The venting member may be disposed between a bent sealing part of the battery case and a side surface of the electrode assembly receiving part facing the bent sealing part.

The present invention also provides a battery module as described in the appended claims. A battery module in accordance with the present disclosure includes a pouch-type batter cell, wherein the battery module may include the pouch-type battery cell, a housing configured to receive one or more pouch-type battery cells, and a venting member configured to discharge internal gas of the pouch-type battery cell. The venting member may be attached to a position facing the sealing part of the pouch-type battery cell, which is an inner surface of the housing.

The venting member may be attached to a position facing the sealing part in a direction in which electrode terminals of the pouch-type battery cell are disposed.

The venting member may be attached to a position facing the sealing part in a direction in which electrode terminals of the pouch-type battery cell are not disposed.

The present invention also provides a battery pack as described in the appended claims. A battery pack in accordance with the present disclosure is configured to receive the pouch-type battery cell or a battery module including the same therein, in which the battery pack may include a venting member configured to penetrate a battery case of the pouch-type battery cell by deforming its shape due to a change of temperature, the venting member being added to an end plate coupled to electrode terminals of the pouch-type battery cell or a cooling fin contacting the pouch-type battery cell.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings such that the preferred embodiments of the present invention can be easily implemented by those skilled in the art to which the present invention pertains.

In the case in which one part is said to be connected to another part in the specification, not only may the one part be directly connected to the another part, but also, the one part may be indirectly connected to the another part via a further part.

A pouch-type battery cell according to the present invention may comprise a battery case including a metal layer and a polymer resin layer, wherein the battery case may include an electrode assembly receiving part formed on at least one of an upper case and a lower case, and a venting member disposed on an outer surface of the electrode assembly receiving part, which is an adjacent portion of a sealing part of the battery case, and the venting member made of a shape memory alloy that is deformed to penetrate the battery case when the temperature of the battery cell increases.

The battery case may be configured to have a structure including an outer resin layer made of a material that is not affected by the external environment; a metal layer for preventing inflow of gas and moisture and for preventing leakage of electrolyte; and an inner resin layer for sealing the battery case.

The electrode assembly may be classified into a jelly-roll type (wound type) electrode assembly, which is configured to have a structure in which long sheet type positive electrodes and long sheet type negative electrodes are wound in the state in which separators are interposed respectively between the positive electrodes and the negative electrodes, a stacked type electrode assembly, which is configured to have a structure in which a plurality of positive electrodes cut so as to have a predetermined size and a plurality of negative electrodes cut so as to have a predetermined size are sequentially stacked in the state in which separators are interposed respectively between the positive electrodes and the negative electrodes, a stacked/folded type electrode assembly, which is configured to have a structure in which bi-cells or full cells, each of which is configured to have a structure in which predetermined numbers of positive electrodes and negative electrodes are stacked in the state in which separators are disposed respectively between the positive electrodes and the negative electrodes, are wound using a separation sheet, or a laminated/stacked type electrode assembly, which is configured to have a structure in which bi-cells or full cells are stacked and laminated in the state in which separators are disposed respectively between the bi-cells or the full cells.

The electrode assembly may be configured to have only one type of electrode assembly, or may be configured to have two or more types of electrode assemblies having different shapes.

When the electrode assemblies are configured to have two or more types of electrode assemblies, the electrode assembly receiving part may have a stepped structure in consideration of the fact that the size of the electrode assemblies may be different from each other on a plane.

The venting member may be made of a shape memory alloy, which is a metal alloy having a property of returning to its original shape before deformation when it is above the transition temperature, even if the deformation state is maintained at or below the transition temperature. The shape memory alloy may typically be made of a titanium-nickel-based alloy or a copper-zinc-aluminum-based alloy.

The venting member may be formed in a straight shape at a normal temperature, and at least one end thereof may be bent when the temperature increases. Thus, as the venting member is bent in an inward direction of the battery case, a through hole is formed in the battery case to discharge gas.

Hereinafter, a normal temperature form of a venting member is referred to as a deformed form (state), and returning to the form of the venting member before deformation above the transition temperature is referred as a recovered form (state).

In order to easily form a through hole for discharging gas, the venting member may have a pointed shape at the end of the portion to be deformed and recovered.

In this regard, <FIG> shows a perspective view of venting members before and after deformation of the venting members.

Referring to <FIG>, a venting member <NUM> has a generally thin cylindrical shape, and is deformed in a straight form at a normal temperature. However, when the venting member <NUM> is above the transition temperature, a right end of the venting member <NUM> is bent because the venting member <NUM> is recovered to the form before deformation.

The venting member <NUM> has a flat left end that does not bend above the transition temperature, while the right end of the venting member <NUM> is bent at a temperature above the transition temperature and has a pointed shape. Therefore, it is advantageous to form a through hole in the battery case.

A venting member <NUM> has a generally thin cylindrical shape, and is deformed in a straight form at a normal temperature. However, when the venting member <NUM> is above the transition temperature, both ends of the venting member <NUM> are bent in the same direction because the venting member <NUM> is recovered to the form before deformation.

The venting member <NUM> is formed in a pointed shape at the left and right ends that are bent when it is above the transition temperature.

A venting member <NUM> has a generally thin and flat rectangular pillar shape, and is deformed in a straight form at a normal temperature. However, when the venting member <NUM> is above the transition temperature, a right end of the venting member <NUM> is bent because the venting member <NUM> is recovered to the form before deformation.

The venting member <NUM> has a flat left end that does not bend above the transition temperature, while the right end of the venting member <NUM> is bent above the transition temperature and has a pointed shape. Therefore, it is advantageous to form a through hole in the battery case.

When the venting member according to the present invention becomes in a recovered form in a state where it is bent from a straight deformed form, a portion of the venting member penetrates through the battery case and is bent into the battery cell. Thus, a space for receiving the bent venting member inside the battery cell is required.

For example, when a stacked type electrode assembly is used as the electrode assembly, the space where an electrode tab and an electrode lead connecting part are positioned may be used as a space for receiving the bent venting member.

As a first embodiment according to the present invention, <FIG> shows a perspective view of a pouch-type battery cell including a unidirectional electrode assembly and an electrode assembly receiving part formed only in the upper case.

Referring to <FIG>, a pouch-type battery cell <NUM> has a structure in which a sealing part of outer edges of an upper case <NUM>, in which an electrode assembly receiving part <NUM> is formed, and a sealing part of outer edges of a lower case <NUM> of a flat shape are sealed.

The electrode assembly receiving part <NUM> is configured to receive a unidirectional electrode assembly in which a positive electrode terminal <NUM> and a negative electrode terminal <NUM> are formed in one direction. A venting member <NUM> is disposed on an outer surface of the electrode assembly receiving part <NUM>, which is an adjacent portion of a sealing part <NUM> where the positive electrode terminal <NUM> and the negative electrode terminal <NUM> are disposed.

The venting member <NUM> may have a structure of any one of the venting members shown in <FIG> and becomes a recovered form as one end or both ends of the venting member are bent toward the battery case above the transition temperature. A through hole is formed in the battery case by the venting member which is in the recovered form, and internal gas of the battery cell can be discharged through the through hole.

However, it is preferable that the end of the bent venting member <NUM> is not in contact with the electrode terminals. Therefore, when using the unidirectional electrode assembly as shown in <FIG>, the venting members <NUM> and <NUM>, which are bent such that only one end thereof becomes the recovered form, may be used and the bent end of the venting member <NUM> may be received in the internal space of the battery cell disposed between the positive electrode terminal <NUM> and the negative electrode terminal <NUM>.

As a second embodiment according to the present invention, <FIG> shows a plan view of a pouch-type battery cell including a bidirectional electrode assembly.

Referring to <FIG>, a pouch-type battery cell <NUM> is configured to have an electrode assembly receiving part <NUM> formed in an upper case <NUM>, and the electrode assembly receiving part <NUM> is configured to receive a bidirectional electrode assembly in which a positive electrode terminal <NUM> and a negative electrode terminal <NUM> protrude in opposite directions.

A lower case of the pouch-type battery cell <NUM> may be a flat shape or may have a structure in which an electrode assembly receiving part is formed.

A venting member <NUM> is disposed on an outer surface of the electrode assembly receiving part <NUM>, which is an adjacent portion of a sealing part <NUM> where the positive electrode terminal <NUM> is disposed. A venting member <NUM> is disposed on an outer surface of the electrode assembly receiving part <NUM>, which is an adjacent portion of a sealing part <NUM> where the negative electrode terminal <NUM> is disposed.

When the pouch-type battery cell includes the bidirectional electrode assembly as shown in <FIG>, it is preferable that a plurality of exhaust ports are formed so that internal gas of the battery cell can be discharged quickly. Thus, the venting members <NUM> and <NUM> may apply a recovered form such that both ends thereof are bent, as shown in the venting member <NUM> of <FIG>. The bent ends of the venting members <NUM> and <NUM> may be received in the internal space of the battery cell disposed between the positive electrode terminal <NUM> and the negative electrode terminal <NUM>.

The pouch-type battery cell <NUM> of <FIG> may have a structure in which an electrode assembly receiving part is formed in the lower case. In such case, venting members may be additionally added to each of an outer surface of the electrode assembly receiving part formed in the lower case, which is an adjacent portion to the sealing portion <NUM> where the positive electrode terminal <NUM> is disposed and an outer surface of the electrode assembly receiving part formed in the lower case, which is an adjacent portion of the sealing portion <NUM> where the negative terminal <NUM> is disposed.

When the electrode assembly receiving part is formed in each of the upper case and the lower case, the size of the electrode assembly may be increased, and thus gas generation due to internal side reactions in the battery cell may increase. Therefore, rapid exhaust can be achieved by adding the venting members to the upper case and the lower case, respectively. Moreover, when using a venting member in which both ends are deformed in a recovered form, such as the venting member <NUM> of <FIG>, it is preferable to obtain a fast exhaust effect since the number of exhaust ports is increased.

As a third embodiment according to the present invention, <FIG> shows an exploded perspective view of a pouch-type battery cell including a unidirectional electrode assembly and an electrode assembly receiving part formed in an upper case and a lower case, respectively.

Referring to <FIG>, a pouch-type battery cell <NUM> is configured to have an electrode assembly receiving part <NUM> formed in an upper case <NUM> and an electrode assembly receiving part <NUM> formed in a lower case <NUM>. The pouch-type battery cell <NUM> has a structure in which the unidirectional electrode assembly in which a positive electrode terminal <NUM> and a negative electrode terminal <NUM> protrude in the same direction is received therein.

A venting member <NUM> is disposed on an outer surface of the electrode assembly receiving part <NUM> of the upper case <NUM>, which is an adjacent portion of a sealing part <NUM> where the positive electrode terminal <NUM> and the negative electrode terminal <NUM> are disposed. A venting member <NUM> is disposed on an outer surface of the electrode assembly receiving part <NUM> of the upper case <NUM>, which is an adjacent portion of the sealing part <NUM> where the positive electrode terminal <NUM> and the negative electrode terminal <NUM> are disposed.

As the pouch-type battery cell <NUM> uses the unidirectional electrode assembly, the venting members <NUM> and <NUM>, such as the venting member <NUM> of <FIG>, use a venting member in which only one end thereof is bent in a recovered form. The ends of the bent venting members <NUM> and <NUM> may be received in the battery cell internal space disposed between the positive electrode terminal <NUM> and the negative electrode terminal <NUM>.

As in the pouch-type battery cells of <FIG>, when a venting member is disposed on an outer surface of an electrode assembly receiving part, which is an adjacent portion of a sealing part in a direction in which electrode terminals are disposed, the venting member is disposed in a deformed state at the adjacent portion of a sealing part where the electrode terminals are formed, and a bent portion of the venting member in a recovered state is received in a portion treated as dead space inside the battery cell. Thus, the problem of increasing the size of the battery cell can be prevented due to the addition of the venting member.

As a fourth embodiment according to the present invention, the venting member may be disposed on an outer surface of an electrode assembly receiving part in a direction in which electrode terminals are not disposed.

In this regard, <FIG> shows a perspective view of a pouch-type battery cell including a bidirectional electrode assembly and having an electrode assembly receiving part formed only in an upper case.

Referring to <FIG>, a pouch-type battery cell <NUM> may have an electrode assembly receiving part <NUM> formed on an upper case <NUM>, and a lower case <NUM> may be a flat shape or may have a structure in which the electrode assembly receiving part is formed.

In the pouch-type battery cell <NUM>, the electrode assembly receiving part <NUM> is configured to receive a bidirectional electrode assembly in which a positive electrode terminal <NUM> and a negative electrode terminal <NUM> protrude in opposite directions.

One or more venting members <NUM> may be disposed on outer surfaces of the electrode assembly receiving part <NUM> of the upper case <NUM>, which are adjacent portions of sealing parts <NUM> and <NUM> where the positive electrode terminal <NUM> and the negative electrode terminal <NUM> are not disposed.

On the other hand, when an electrode assembly receiving part is formed in the lower case <NUM>, a venting member may be additionally disposed on an outer surface of the electrode assembly receiving part of the lower case <NUM>, which is an adjacent portion of the sealing parts <NUM> and <NUM> where the electrode terminals are not disposed.

Moreover, in addition to the venting member <NUM> disposed adjacent to the negative terminal <NUM>, a venting member may be further added to a position adjacent to the positive electrode terminal <NUM> which is symmetrical thereto.

Unlike the venting members shown in <FIG>, the venting members <NUM> are disposed at the adjacent portions of the sealing parts where electrode terminals are not disposed, and thus it is preferable that only the ends of the venting members <NUM> in a direction close to the electrode terminals are in a recovered form. In addition, the ends of the recovered venting member may be received in the battery cell internal spaces disposed at both sides of the positive electrode terminal <NUM> and the negative electrode terminal <NUM>.

In addition, the venting members <NUM> may be disposed on outer surfaces of the electrode assembly receiving part <NUM> of the upper case <NUM>, which are adjacent portions of the sealing parts where the positive electrode terminal <NUM> and/or the negative electrode terminal <NUM> are disposed.

As a fifth embodiment according to the present invention, the venting member may be disposed between a bent sealing part of a battery case and a side surface of an electrode assembly receiving part facing the bent sealing part.

In this regard, <FIG> shows a perspective view of a pouch-type battery cell in which a sealing part is bent.

Referring to <FIG>, a pouch-type battery cell <NUM> is configured to have an electrode assembly receiving part <NUM> formed in an upper case <NUM>, and an electrode assembly receiving part <NUM> formed in a lower case <NUM>. The pouch-type battery cell <NUM> has a structure in which a unidirectional electrode assembly in which a positive electrode terminal <NUM> and a negative electrode terminal <NUM> protrude in the same direction is received therein.

The pouch-type battery cell <NUM> is in a state in which a sealing part in a direction in which the electrode terminals do not protrude is bent, and thus a venting member <NUM> is disposed between a bent sealing part <NUM> and a side surface of the electrode assembly receiving part <NUM> of the lower case <NUM>.

The venting member <NUM> has the same shape as the venting member <NUM> of <FIG>, and thus only an end in a direction in which the negative electrode terminal <NUM> is disposed is in a recovered form that can penetrate the battery case.

In addition, a venting member may be further disposed between the opposite side of the bent sealing part <NUM> and the side surface of the electrode assembly receiving part. The end of the recovered venting member <NUM> may be received in the battery cell internal space outside the positive electrode terminal <NUM> and the negative electrode terminal <NUM>.

In the case of the pouch-type battery cell <NUM>, although the venting member is not disposed at an adjacent portion of a sealing portion <NUM> in a direction in which the electrode terminals are disposed, the venting member is disposed between the bent sealing part and the side surface of the electrode assembly receiving part. Thus, it is preferable to apply a thin and flat rectangular pillar-shaped venting member <NUM> such as the venting member <NUM> of <FIG>.

The method of adding the venting member is not particularly limited as long as the venting member may be stably fixed to the outer surface of the pouch-type battery cell. For example, an adhesive material may be applied to the outer surface of the venting member to be attached, or an apparatus capable of physically mounting the venting member may be added and fixed.

Specifically, the venting member may be attached using an adhesive tape, or a groove or the like for inserting the venting member may be used by molding the pouch case. A method of attaching or physically fixing the venting member on the sealing part by using a separate member such as a clip for fitting the venting member to the pouch case or the electrode terminals may be used.

The present invention also provides a battery module including the pouch-type batter cell, wherein the battery module may include the pouch-type battery cell, a housing configured to receive one or more pouch-type battery cells, and a venting member configured to discharge gas in the pouch-type battery cell. The venting member may be attached to a position facing a sealing part of the pouch-type battery cell, which is an inner surface of the housing. In addition, it is possible to manufacture and use a housing including a structure for fitting the venting member into the inner surface of the housing or inserting the venting member to be mounted on the inner surface of the housing.

Specifically, the venting member may be attached or fixed to a position facing a sealing part in a direction in which electrode terminals of the pouch-type battery cell are disposed, or a position facing a sealing part in a direction in which electrode terminals of the pouch-type battery cell is not disposed.

In this regard, <FIG> shows an exploded view of a battery module including a pouch-type battery cell and a venting member.

Referring to <FIG>, the battery module includes a pair of housings <NUM> and <NUM> surrounding an outer surface of a pouch-type battery cell <NUM>. A venting member <NUM> is disposed at a position facing a sealing part <NUM> in a direction in which electrode terminals of the pouch-type battery cell <NUM> are not disposed, which is an inner surface of the housing <NUM>.

In addition, unlike what is shown in <FIG>, the battery module according to the present invention may have a form in which a venting member is added to an inner surface of a housing facing a sealing part <NUM> in a direction in which electrode terminals are disposed.

The vent member <NUM> may be bent toward the pouch-type battery cell <NUM> at the transition temperature to be in a recovered form, and thus, a through hole for discharging gas may be formed in the battery case by recovering the venting member.

As shown in <FIG>, since the venting member is added to a portion treated as dead space inside the battery module, which is an adjacent portion of the pouch-type battery cell, the size of the battery module may be prevented from being changed due to the addition of the venting member.

The present invention also provides a battery pack configured to receive the pouch-type battery cell or a battery module including the same therein, in which a venting member penetrating a battery case of the pouch-type battery cell by deforming its shape due to a change of temperature may be added to an end plate coupled to an electrode terminal of the pouch-type battery cell or a cooling fin contacting the pouch-type battery cell.

In addition, the venting member may be fixed by mounting a groove, a ring, a clip, or the like to an inner surface of the housing, the end plate, or the cooling fin.

As such, the venting member is not a structure added to the outer surface of the pouch-type battery cell, and may be attached to the end plate or the cooling fin located adjacent to the pouch-type battery cell. Thus, when the venting member becomes in a recovered state above the transition temperature, a through hole for discharging gas may be formed in the battery case while the venting member is being bent toward the pouch-type battery cell.

The structure of the end plate and the cooling fins is not particularly limited, and a structure that does not affect the overall size of the battery pack may be applied even if the venting member is applied to a structure that does not affect the overall size.

As such, since a venting member included in the pouch-type battery cell according to the present invention is made of a shape memory alloy, the venting member may be designed to deform its shape at a temperature requiring gas discharge of the pouch-type battery cell.

As described above, the present invention includes a venting member of the shape memory alloy material, it is possible to prevent the explosion and ignition of the battery cell by venting at a desired temperature.

Those skilled in the art to which the present invention pertains will appreciate that various applications and modifications are possible based on the above description, without departing from the scope of the present invention.

As described above, a pouch-type battery cell according to the present invention can be discharged by forming a through-hole in a battery case at a desired temperature.

In addition, by adding a venting member to the outside of the battery cell, it is possible to prevent a problem that the venting member disposed inside the battery cell causes side reactions with electrolyte and the like.

Claim 1:
A pouch-type battery cell (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>), comprising a battery case comprising a metal layer and a polymer resin layer, wherein the battery case comprising:
an electrode assembly receiving part (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) formed on at least one of an upper case (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) and a lower case (<NUM>, <NUM>,<NUM>, <NUM>), and
a venting member (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) disposed on an outer surface of the electrode assembly receiving part (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) as an adjacent portion of a sealing part (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) of the battery case,
wherein the venting member (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) is made of a shape memory alloy that is deformed in a straight form and is recovered to the form before deformation in such way that it penetrates the battery case when the temperature is above the transition temperature of the shape memory alloy;
wherein the case comprises a space for receiving the bent venting member (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>).