KR20210029121A - Energy Storage Module - Google Patents

Abstract

The present invention relates to an energy storage module capable of reducing a fire risk of battery cells and improving safety by minimizing a fire spreading between adjacent battery cells when a fire occurs. As an example, disclosed is an energy storage module which includes: a plurality of battery cells arranged in a longitudinal direction so that long side surfaces thereof face each other; a plurality of insulating spacers interposed between the long side surfaces of the plurality of battery cells; a cover plate having an accommodating space therein and accommodating the plurality of battery cells and the plurality of insulating spacers; a top plate having a duct coupled to an upper portion of the cover plate and formed at positions corresponding to vents of the plurality of battery cells, and having a chemical hole formed at positions corresponding to the insulating spacers; a top cover coupled to an upper portion of the top plate and having a discharge hole at a position corresponding to the duct; and an extinguisher sheet located between the top cover and the top plate and configured to emit a fire extinguishing agent at a preset temperature or above, wherein the insulating spacers include: a first sheet having flame retardancy or nonflammability; and second sheets having heat insulating properties which are attached to both surfaces of the first sheet through an adhesive member, respectively.

Description

Energy Storage Module

The present invention relates to an energy storage module capable of improving stability.

The energy storage module is connected to renewable energy and power systems such as solar cells, and is configured to store power when the power demand of the load is low, and then use the stored power when the power demand of the load is large. It refers to a device including a large number of battery cells composed of.

Typically, a plurality of battery cells are accommodated in a plurality of trays, a plurality of trays are stored in a rack, and a plurality of racks are stored in a container box.

Meanwhile, a fire has recently occurred in an energy storage module, and due to the nature of the energy storage module, when a fire occurs, there is a problem that it is not easy to extinguish. Since the energy storage module is composed of a plurality of battery cells, it is common to have a high capacity and high output, and accordingly, a technology for enhancing safety is being studied.

The present invention provides an energy storage module capable of improving stability by reducing the risk of fire of a battery cell and minimizing the transition between battery cells in the event of a fire.

The energy storage module according to various embodiments of the present invention includes a plurality of battery cells arranged along a length direction so that their long sides face each other, a plurality of insulating spacers interposed between the long sides of the plurality of battery cells, and A cover plate having an accommodation space and accommodating the plurality of battery cells and the plurality of insulating spacers, a duct coupled to an upper portion of the cover plate and formed at a position corresponding to a vent of the plurality of battery cells, the An upper plate having a chemical solution hole formed at a position corresponding to the insulating spacer, an upper cover coupled to an upper portion of the upper plate and including a discharge hole at a position corresponding to the duct, and located between the upper cover and the upper plate, It includes a fire extinguishing sheet for spraying a fire extinguishing agent at a predetermined temperature or higher, wherein the insulating spacer includes a first sheet having flame retardancy or non-flammability, and a second sheet having heat insulating properties on both sides of the first sheet through an adhesive member. Can be.

The first sheet may be ceramic paper, and the second sheet may be MICA.

The first sheet may be a ceramic fiber containing an alkaline earth metal.

The plurality of battery cells may be spaced apart from each other by a first separation distance between opposite long side surfaces, and a thickness of the insulating spacer may be less than 50% of the first separation distance.

The fire extinguishing agent sprayed from the fire extinguishing sheet may be applied to a space spaced apart from the insulating spacer and the battery cell through the chemical solution hole, so that it may contact the long side surface of the battery cell.

The insulating spacer has a size in the width direction smaller than twice the size in the height direction, and the first sheet and the second sheet may include a sheet portion having both ends of the first sheet and the second sheet adhered by an adhesive member.

The insulating spacer may further include an edge portion of a plastic material formed by insert injection so as to surround the edge of the sheet portion.

The width of the edge portion may be any one of 3mm to 6mm.

One side of the insulating spacer may face a long side of one battery cell, and the other side may face a long side of another battery cell.

The first sheet and the second sheet may have a central portion spaced apart from each other, and an air flow path capable of air movement may be provided.

The insulating spacer has a size in the width direction greater than twice the size in the height direction,

A predetermined region of the first sheet and the second sheet may be adhered from upper and lower ends by an adhesive member.

The insulating spacer may have one side facing the long side surfaces of the two battery cells and the other side facing the long side surfaces of the other two battery cells.

The battery cell may include a negative electrode including a negative current collector, a negative active material layer disposed on the negative current collector, and a negative functional layer disposed on the negative active material layer; And a positive electrode including a positive electrode current collector and a positive electrode active material layer positioned on the positive electrode current collector, wherein the negative electrode functional layer includes plate-shaped polyethylene particles, and the positive electrode active material layer includes cobalt, manganese, nickel, and these A first positive electrode active material including at least one of a composite oxide of a metal and lithium selected from a combination of, and a second positive electrode active material including a compound represented by the following Formula 1 may be included.

[Formula 1]

Li _a Fe ₁ - _x M _x PO ₄

In Formula 1, 0.90 ≤ a ≤ 1.8, 0 ≤ x ≤ 0.7, M is Mg, Co, Ni or

It may be a combination of these.

The average particle size (D50) of the plate-shaped polyethylene particles may be 1 μm to 8 μm.

The average particle size (D50) of the plate-shaped polyethylene particles may be 1 μm to 8 μm.

The plate-shaped polyethylene particles may have a thickness of 0.2 µm to 4 µm.

The first positive electrode active material and the second positive electrode active material may be included in a weight ratio of 97:3 to 80:20.

The energy storage module according to the present invention primarily suppresses ignition by allowing a shutdown function inside the battery cell through the material of the negative electrode and the positive electrode active material, and when a vent operates or ignition occurs in the battery cell, extinguishing and Cooling can be performed quickly to prevent heat from spreading to adjacent battery cells.

1 is a perspective view of an energy storage module according to an embodiment of the present invention.
FIG. 2 is an enlarged view of part A of FIG. 1.
3 is an exploded perspective view of an energy storage module according to an embodiment of the present invention.
4 is an exploded perspective view illustrating a position at which a fire extinguishing sheet is coupled to a top cover of an energy storage module according to an embodiment of the present invention from a bottom surface.
5 is a perspective view illustrating a state in which a battery cell and an insulating spacer are disposed on a lower plate in an energy storage module according to an embodiment of the present invention.
6A is a partial diagram illustrating a state in which an energy storage module according to an embodiment of the present invention is coupled to a rack.
6B and 6C are diagrams illustrating an internal gas movement path of a battery cell through a duct of an energy storage module according to an embodiment of the present invention.
7 is a perspective view showing a state in which the fire extinguishing sheet is coupled to the upper plate of the energy storage module according to an embodiment of the present invention.
8 is an enlarged view of part B of FIG. 7.
9A and 9B are conceptual diagrams illustrating a state in which a fire extinguishing sheet operates in an energy storage module according to an embodiment of the present invention.
10 is a cross-sectional view taken along line 10-10 of FIG. 1.
11 is a perspective view illustrating an insulating spacer in an energy storage module according to an embodiment of the present invention.
12A and 12B are exploded perspective views illustrating an exemplary configuration of a sheet portion of an insulating spacer in an energy storage module according to an embodiment of the present invention.
13 is a cross-sectional view taken along line 13-13 after the sheet portion of FIG. 12A is coupled.
14 is an enlarged view of part C of FIG. 10.
15 is a perspective view of an energy storage module according to another embodiment of the present invention.
16 is a bottom perspective view of an energy storage module according to another embodiment of the present invention.
17 is a cross-sectional view taken along line 17-17 of FIG. 15.
18 is a perspective view illustrating a state in which a battery cell and an insulating spacer are disposed on a cover plate in an energy storage module according to another embodiment of the present invention.
19A and 19B are perspective and exploded perspective views showing the configuration of an insulating spacer in an energy storage module according to another embodiment of the present invention.
20 is a cross-sectional perspective view taken along line 20-20 of FIG. 15.
21A and 21B are perspective and cross-sectional views of a battery cell used in an energy storage module according to an embodiment of the present invention.
22 is an SEM photograph of spherical polyethylene particles in an aqueous dispersion state.
23 is a SEM photograph of polyethylene particles according to an embodiment.
24 is a SEM photograph of an electrode composition according to an embodiment.
25 is a graph analyzing the particle size distribution of plate-shaped polyethylene particles included in the electrode compositions according to Examples 1 to 3.
26 is a graph evaluating the rate of increase in resistance of an electrode plate according to temperature.
27 is a graph evaluating capacity retention for 150 cycles of a rechargeable lithium battery according to an embodiment.
28 is a schematic diagram of a coin symmetric battery manufactured to evaluate the increase rate of the resistance of the electrode plate.
29 is an SEM photograph showing a cross section of a surface of a negative electrode during shutdown of a lithium secondary battery not including a positive electrode according to an exemplary embodiment.
30 is a SEM photograph showing a cross-section of a surface of a negative electrode during shutdown of a lithium secondary battery including a negative electrode including a negative electrode functional layer and a positive electrode at the same time, according to an exemplary embodiment.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The embodiments of the present invention are provided to more completely describe the present invention to those of ordinary skill in the art, and the following examples may be modified in various other forms, and the scope of the present invention is as follows. It is not limited to the examples. Rather, these embodiments are provided to make the present disclosure more faithful and complete, and to fully convey the spirit of the present invention to those skilled in the art.

In addition, in the following drawings, the thickness or size of each layer is exaggerated for convenience and clarity of description, and the same reference numerals refer to the same elements in the drawings. As used herein, the term “and/or” includes any and all combinations of one or more of the corresponding listed items. In addition, in the present specification, "connected" means not only the case where the A member and the B member are directly connected, but also the case where the member A and the member B are indirectly connected by interposing the member C between the member A and the member B. do.

The terms used in this specification are used to describe specific embodiments, and are not intended to limit the present invention. As used herein, the singular form may include the plural form unless the context clearly indicates another case. Also, as used herein, “comprise” and/or “comprising” specify the presence of the mentioned shapes, numbers, steps, actions, members, elements and/or groups thereof. And does not exclude the presence or addition of one or more other shapes, numbers, actions, members, elements and/or groups.

In this specification, terms such as first and second are used to describe various members, parts, regions, layers and/or parts, but these members, parts, regions, layers and/or parts are limited by these terms. It is self-evident that it should not be. These terms are only used to distinguish one member, part, region, layer or portion from another region, layer or portion. Accordingly, the first member, part, region, layer or part to be described below may refer to the second member, part, region, layer or part without departing from the teachings of the present invention.

Terms relating to space such as “beneath”, “below”, “lower”, “above”, and “upper” are used in conjunction with an element or feature shown in the drawing. It is used for easy understanding of other elements or features. Terms related to these spaces are for easy understanding of the present invention according to various process conditions or use conditions of the present invention, and are not intended to limit the present invention. For example, if an element or feature in a figure is flipped over, an element described as “lower” or “below” becomes “top” or “above”. Thus, "below" is a concept encompassing "top" or "bottom".

Hereinafter, a configuration of a secondary battery according to an embodiment of the present invention will be described.

1 is a perspective view of an energy storage module according to an embodiment of the present invention. FIG. 2 is an enlarged view of part A of FIG. 1. 3 is an exploded perspective view of an energy storage module according to an embodiment of the present invention. 4 is an exploded perspective view illustrating a position at which a fire extinguishing sheet is coupled to a top cover of an energy storage module according to an embodiment of the present invention from a bottom surface. 5 is a perspective view illustrating a state in which a battery cell and an insulating spacer are disposed on a lower plate in an energy storage module according to an embodiment of the present invention.

First, referring to FIGS. 1 to 5, the energy storage module 100 according to an embodiment of the present invention includes a cover member 110, a battery cell 120, an insulating spacer 130, an upper plate 140, It may include a configuration of the fire extinguishing sheet 150 and the upper cover 160.

First, the cover member 110 provides a space for accommodating the battery cell 120 and the insulating spacer 130 therein. The cover member 110 includes a lower plate 111, an end plate 112, and a side plate 113, and may have a space in which the battery cell 120 and the insulating spacer 130 are disposed. In addition, the cover member 110 may fix the positions of the battery cells 120 and the insulating spacers 130 and protect the battery cells 120 from external impacts.

The battery cells 120 may be disposed alternately with the insulating spacer 130 on the upper surface of the lower plate 111 of the cover member 110. Specifically, a plurality of battery cells 120 are arranged in two rows along the upper surface of the lower plate 111 so that their long sides face each other, and an insulating spacer 130 may be positioned between the long sides of the battery cells 120. I can.

In the battery cell 120, the electrode assembly may be accommodated in the case 121, and the electrode assembly is in a state in which a separator is positioned between a positive electrode plate and a negative electrode plate coated with an active material on a coating portion, for example, It can be constructed in a way that is wound, stacked or laminated. In addition, the cap plate 124 may seal the upper portion of the case 121. In addition, a vent 124a formed to have a thinner thickness compared to other regions may be formed at approximately the center of the cap plate 124. In addition, in the battery cell 120, regions of the positive plate and the negative plate to which the active material is not applied, for example, electrode terminals 122 and 123 electrically connected to the uncoated portion may be exposed above the cap plate 124. Here, the electrode terminals 122 and 123 may be referred to as a first electrode terminal 122 and a second electrode terminal 123, respectively, and may be a negative electrode and a positive electrode terminal, respectively. Of course, on the contrary, the first electrode terminal 122 and the second electrode terminal 123 may be positive and negative terminals, respectively. Meanwhile, through the composition of the active material of the battery cell 120, ignition can be reduced to increase stability, and the composition of such an active material will be described later.

The insulating spacer 130 is interposed between the battery cells 120 to prevent the battery cells 120 from contacting each other, thereby maintaining electrical independence. In addition, by maintaining a predetermined distance between the insulating spacer 130 and the battery cell 120, a passage for external air or a passage for moving the extinguishing chemical solution may be provided so that the battery cell 120 is cooled. Such an insulating spacer 130 may be used by mixing a flame-retardant or non-flammable sheet to prevent flame from spreading and an insulating sheet to prevent heat from spreading when a fire occurs in the battery cell 120, such an insulating spacer The configuration of (130) will be described later.

The upper plate 140 may be coupled to the upper portion of the cover member 110. The upper plate 140 may be coupled to the cover member 110 while covering the upper portion of the battery cell 120. In addition, the first electrode terminal 122 and the second electrode terminal 123 of the battery cell 120 are exposed above the upper plate 140, and the bus bar 145 is coupled to each terminal, so that the battery cell 120 can be connected in series, parallel, or serial-parallel form.

Meanwhile, the upper plate 140 includes a duct 141 corresponding to the vents 124a formed on the upper surfaces of the plurality of battery cells 120. A plurality of ducts 141 may be arranged in one direction, for example, along a length direction. Accordingly, the gas discharged by operating the vent 124a of the battery cell 120 may move upward along the duct 141 of the upper plate 140. The specific structure and operation of the duct 141 will be described later.

The fire extinguishing sheet 150 is located between the upper plate 140 and the upper cover 160. The fire extinguishing sheet 150 may be formed as at least one member extending along one direction of the upper plate 140, for example, a length direction. In addition, the fire extinguishing sheet 150 may be provided with an open hole 151 penetrating between the upper surface and the lower surface at a position corresponding to the duct 141 of the upper plate 140. Accordingly, the fire extinguishing sheet 150 may be positioned so that the open hole 151 matches the duct 141 of the upper plate 140. In addition, the fire extinguishing sheet 150 may be coupled to the lower surface 160b of the upper cover 160. As the fire extinguishing sheet 150 is coupled to the lower portion of the upper cover 160, the fire extinguishing sheet 150 may be located above the upper plate 140. The configuration and operation of the fire extinguishing sheet 150 will be described later.

The upper cover 160 is coupled to the upper portion of the upper plate 140. The upper cover 160 may cover the upper plate 140 and the bus bar 145. In addition, the upper cover 160 may also cover the fire extinguishing sheet 150 coupled to the lower surface 160b, thereby protecting them from an impact applied from the upper surface 160a of the upper cover 160. In addition, the upper cover 160 may include a discharge hole 161. In addition, the upper cover 160 may further include a protrusion 162 spaced apart from the outer periphery of the discharge hole 161 and protruding downward. The open hole 151 of the fire extinguishing sheet 150 may be coupled to the outside of the protrusion 162, and the duct 141 may be coupled to the inner side of the protrusion 162. The discharge hole 161 may be formed by arranging a plurality of discharge holes 161 along one direction, for example, a length direction of the upper cover 160. In addition, the discharge hole 161 may be formed at a position corresponding to the duct 141 of the upper plate 140. In addition, the discharge hole 161 may also be provided in the form of a hole penetrating between the upper surface and the lower surface so as to be spaced apart from each other like the duct 141. Accordingly, the gas discharged by operating the vent 124a of the battery cell 120 may be discharged to the outside along the duct 141 of the upper plate 140 and the discharge hole 161 of the upper cover 160. have. In addition, the upper cover 160 may prevent a user from contacting with the internal structure of the upper cover 160 to promote safety.

Hereinafter, the duct 141 of the upper plate 140 in the energy storage module according to an embodiment of the present invention will be described in more detail.

6A is a partial diagram illustrating a state in which an energy storage module according to an embodiment of the present invention is coupled to a rack. 6B and 6C are diagrams illustrating an internal gas movement path of a battery cell through a duct of an energy storage module according to an embodiment of the present invention. Here, FIG. 6B is an enlarged cross-sectional view taken along line A-A of FIG. 2, and FIG. 6C is an enlarged cross-sectional view taken along line B-B of FIG. 2.

First, referring to FIG. 6A, a plurality of energy storage modules 100 according to an exemplary embodiment of the present invention may be accommodated in a plurality of shelves 12 of the rack 10, respectively. The energy storage modules 100 may be provided in different numbers according to the required capacity, and may be mounted and fixed on the rack 10. Here, the rack 10 may include a frame 11 forming an overall appearance and a shelf 12 supporting the lower portions of the plurality of energy storage modules 100 by different layers within the frame 11. At this time, the lower surface of one energy storage module 100 may contact the upper surface of the shelf 12, and the lower surface of the other shelf 12 may be positioned at a predetermined interval on the upper surface. In Figure 6a, two shelves 12 are provided in the frame 11, and two energy storage modules 100 are shown to be seated on each shelf 12, but limiting the contents of the present invention by the number no.

In addition, as described above, the duct 141 formed on the upper plate 140 corresponds to the vent 124a of the battery cell 120, and referring to FIGS. 6B and 6C, the vent 124a is operated. The discharged gas moves upward along the duct 141 as indicated by an arrow. In addition, the upper plate 140 may be discharged to the outside through the discharge hole 161 of the upper cover 160 located above the duct 141 when the vent 124a of the battery cell 120 operates. . At this time, by the shelf 12 of the rack 10 accommodating another energy storage module 100 on the top of the upper surface 160a of the upper cover 160, gas is the upper surface 160a of the upper cover 160 ) And the shelf. In this case, the upper surface 160a of the upper cover 160 may be spaced apart from the lower surface of the shelf 12 by a first distance. Here, the first interval may be any one of 3mm to 7mm. When the first interval is 3mm or more, it is easy to discharge heat generated by the energy storage module 100 to the outside. In addition, when the first interval is 7 mm or less, it is easy to form a high-temperature inert gas atmosphere as follows.

On the other hand, the gas discharged from the battery cell 120 through the vent 124a mainly generates an electrolyte vapor component gas having a relatively low temperature of about 170°C, and gradually, a relatively high temperature around 400°C. An inert gas having a is generated. In addition, for a gas having a relatively low temperature, the upper plate 140 made of heat-resistant plastic and the upper cover 160 may be maintained without melting. Meanwhile, when the separator melts as the internal temperature of the battery cell 120 increases, a high-temperature inert gas may be generated together with a flame. As described above, the inert gas at this time fills the space between the upper surface 160a of the upper cover 160 and the shelf 12 to form an atmosphere, thereby preventing the introduction of oxygen. In addition, the inert gas may remain filled in the inner space of the duct 141.

Such an inert gas may serve to block the flame generated from the battery cell 120 from being transmitted to the neighboring battery cell 120 or transmitted to the other energy storage module 100. In addition, in the case of the fire extinguishing sheet 150 located under the upper cover 160, it is operated by a high-temperature inert gas, and may serve to inject a fire extinguishing agent as will be described later.

Hereinafter, the configuration and operation of the fire extinguishing sheet 150 in the energy storage module 100 according to an embodiment of the present invention will be described.

7 is a perspective view showing a state in which the fire extinguishing sheet is coupled to the upper plate of the energy storage module according to an embodiment of the present invention. 8 is an enlarged view of part B of FIG. 7. 9A and 9B are conceptual diagrams illustrating a state in which a fire extinguishing sheet operates in an energy storage module according to an embodiment of the present invention.

First, referring to FIGS. 7 and 8, the fire extinguishing sheet 150 may be positioned between the upper plate 140 and the upper cover 160, as described above. As shown in FIG. 7, the fire extinguishing sheet 150 may have an open hole 151 coupled to the duct 141 of the upper plate 140. In addition, accordingly, the fire extinguishing sheet 150 does not affect the movement of gas through the duct 141.

In addition, referring to FIGS. 8A and 8B, the fire extinguishing sheet 150 may operate in response to heat when a gas, specifically, a relatively high temperature, for example, an inert gas of about 400° C. is generated. At this time, the fire extinguishing agent constituting the fire extinguishing sheet 150 is injected from the fire extinguishing sheet 150 by the hot gas. In addition, since the upper part of the fire extinguishing sheet 150 is blocked by the upper cover 160, the fire extinguishing agent may be sprayed with a directionality toward the lower surface of the upper cover 160. In addition, the fire extinguishing agent may reach the insulating spacer 130 under the upper plate 140 through an open hole 143 formed at the front and rear ends of the duct 141 of the upper plate 140. In addition, the duct 141 is further formed with a chemical solution guide protrusion 142 about the periphery of the open hole 143, so that the movement of the fire extinguishing agent may be additionally guided. On the other hand, as will be described later, the extinguishing agent reaching the insulating spacer 130 may move along the surface of the insulating spacer 130, and accordingly, the extinguishing of the battery cell 120 having ignition is as well as the battery cell 120. Cooling of can be performed.

In addition, the fire extinguishing sheet 150 may have a sheet form in which a capsule-type fire extinguishing agent is accommodated in the exterior material. Here, the fire extinguishing sheet 150 is, as described above, when the temperature of the gas passing through the duct 141 of the upper plate 140 reaches a relatively high temperature of about 400°C, the capsule and the exterior material are opened to Fire extinguishing agents can be sprayed.

Hereinafter, the structure and operation of the battery cell 120 and the insulating spacer 130 in the energy storage module according to an embodiment of the present invention will be described.

10 is a cross-sectional view taken along line C-C of FIG. 1. 11 is a perspective view illustrating an insulating spacer in an energy storage module according to an embodiment of the present invention. 12A and 12B are exploded perspective views illustrating an exemplary configuration of a sheet portion of an insulating spacer in an energy storage module according to an embodiment of the present invention. 13 is a cross-sectional view taken along line D-D after the sheet portion of FIG. 12A is coupled. 14 is an enlarged view of part C of FIG. 10.

The battery cells 120 may be disposed alternately with the insulating spacer 130 on the upper surface of the lower plate 111 of the cover member 110. In this case, the long side surface of the battery cell 120 may face each other while being spaced apart from the long side surface of the adjacent battery cell 120 by a predetermined distance, and an insulating spacer 130 may be interposed therebetween. Here, the first separation distance, which is the separation distance between the long side surfaces of the two battery cells 120, may be any one of 4mm to 6mm. Here, when the first separation distance is less than 4 mm, it is not easy to form an air layer between the insulating spacer 130 and the battery cell 120, and cooling performance may be deteriorated. In addition, when the first separation distance exceeds 6 mm, it may unnecessarily increase the size of the energy storage module 100.

The insulating spacer 130 prevents the battery cells 120 from contacting each other between the battery cells 120, thereby maintaining electrical independence. Such an insulating spacer 130 may have a planar size corresponding to a planar size of a long side of one battery cell 120. That is, the insulating spacer 130 may have one side facing the long side of one battery cell 120 and the other side facing the long side of another battery cell 120.

In addition, the insulating spacer 130 and the long side surface of the battery cell 120 may be spaced apart by a second separation distance, which is a predetermined distance, to form an external air passage. Here, by the external air passage, the battery cell 120 may be cooled by external air.

The insulating spacer 130 may include a sheet portion 131 and an edge portion 132. When a fire occurs in the battery cell 120, the sheet portion 131 may be used by mixing a sheet having flame retardancy or non-flammability to prevent the fire from spreading and an insulating sheet to prevent heat from spreading. In more detail, the sheet portion 131 includes a first sheet 131a having heat insulating properties, and two second sheets having flame retardancy or non-flammability attached to both sides of the first sheet 131a through an adhesive member 131c, respectively. It may include a sheet (131b). In this way, the sheet portion 131 may increase not only flame retardancy and non-flammability, but also heat insulation effect by stacking the first sheet 131a and the second sheet 131b in multiple layers. That is, when the temperature of the battery cell 120 is increased and a flame is generated through the sheet portion 131 in which a plurality of sheets are stacked, the insulating spacer 130 transmits heat or flame to the adjacent battery cell 120. It can be prevented from being transmitted.

Such an insulating spacer 130 may be used by mixing a flame-retardant or non-flammable sheet to prevent flame from spreading and an insulating sheet to prevent heat from spreading when a fire occurs in the battery cell 120, such an insulating spacer The configuration of (130) will be described later.

Here, the first sheet 131a and the second sheet 131b may have the same size. If the thickness of the insulating spacer 130 does not exceed 50% of the first separation distance, it may be easier to move the extinguishing agent to be described later. For example, when the first separation distance is 6mm, the thickness of the insulating spacer 130 is preferably not more than 3mm, and when the first separation distance is 4mm, it is preferable not to exceed 2mm. For example, the first sheet 131a may be any one of 1mm to 1.4mm. In addition, the second sheet 131b may be any one of 0.1mm to 0.2mm. In addition, the adhesive member 131c may be 0.1mm.

For example, ceramic paper may be used for the first sheet 131a, and mica may be used for the second sheet 131b. In addition, the first sheet 131a may further include an airgel, and when the airgel is included, a large air layer may be secured, thereby improving thermal insulation performance. In addition, the first sheet 131a may be a ceramic paper of a refractory insulating material including fibers. In addition, the first sheet (131a) is a ceramic fiber ceramic paper containing an alkaline earth metal (Bio-soluble fiber ceramic paper), it may be an environmentally friendly high-temperature fire-resistant insulating material harmless to the human body.

In addition, the seat portion 131 may include the configuration shown in FIG. 12A or 12B.

The adhesive member 131c is interposed between the second sheet 131b so as to have a predetermined width from both ends of the first sheet 131a, as shown in FIGS. 12A and 13. It is possible to attach between the sheets (131b). In addition, the adhesive member 131c may have the same length as the length direction of the first sheet 131a and the second sheet 131b. That is, both end portions x1 of the first sheet 131a may be adhered to both end portions x1 of the second sheet 131b by the adhesive member 131c.

The adhesive member 131c may have a width of 10 mm to 20 mmm. Here, if the width of the adhesive member 131c is less than 10mm, adhesion between the first sheet 131a and the second sheet 131b may not be easy, and if it exceeds 20mm, the probability of ignition by the adhesive member increases. Can be.

In addition, the adhesive member 131c may use any one of an adhesive having various adhesive components such as a general double-sided tape and an adhesive, and the component of the adhesive member 131c is not limited in the present invention.

Since the adhesive member 131c attaches only both end portions x1 of the sheet portion 131, the central portion x2 between the first sheet 131a and the second sheet 131b may be spaced apart from each other. Accordingly, an air passage 131d may be formed between the first sheet 131a and the second sheet 131b. In addition, when the battery cell 120 swells due to swelling, the seat portion 131 may reduce the compression rate due to the air flow path 131d of the central portion x2.

In addition, as shown in FIG. 12B, the sheet portion 131 has an adhesive member 131c formed in a predetermined area from the upper and lower ends of the first sheet 131a, so that the first sheet 131a and the second sheet 131b Can be attached between. In addition, the adhesive member 131c may have the same width as the width direction of the first sheet 131a and the second sheet 131b. That is, the upper and lower ends of the first sheet 131a may be adhered to the upper and lower ends of the second sheet 131b by the adhesive member 131c.

If the size of the sheet part 131 in the width direction is less than twice the size in the height direction, as shown in FIG. 12A, adhesive members 131c may be attached to both ends, but the size in the width direction is the size in the height direction. When the adhesive member (131c) is attached to both ends when it is twice as large as compared to, since the adhesive area is reduced compared to the area of the sheet portion, the adhesive performance may be deteriorated.

Accordingly, when the size of the sheet portion 131 is twice or more than the size in the height direction, the sheet portion 131 may be attached to the upper and lower ends with the adhesive member 131c to increase the bonding area, thereby improving adhesion performance. The configuration of the sheet portion 131 may be the same as the sheet portion 131 shown in FIGS. 12A and 13 except for the attachment position of the adhesive member 131c.

However, when the upper and lower ends of the sheet part 131 are attached by the adhesive member 131c, the adhesion performance is improved, so it is not necessary to form a separate edge part 132.

In addition, in the case of the edge portion 132, it may be formed along the edge of the sheet portion 131. The rim portion 132 may be formed of a plastic material, and is coupled to the rim of the sheet portion 131 through double injection, thereby fixing the shape of the sheet portion 131. For example, the rim portion 132 may be made of conventional polyethylene or polypropylene. Preferably, the width of the edge portion 132 may have a width of 3mm to 6mm. Here, when the width of the edge portion 132 is less than 3mm, it may not be easy to fix the seat portion 131, and when it exceeds 6mm, the combustion probability of the edge portion 132 made of plastic may increase.

Meanwhile, as mentioned above, when the extinguishing chemical is applied from the upper portion of the insulating spacer 130, it may move downward along the surface of the sheet portion 131. Therefore, the extinguishing chemical liquid comes into contact with the case 121 of the battery cell 120, and thus, the extinguishing of the battery cell 120 as well as the cooling function can be performed. Hereinafter, the movement of the digestive liquid will be described in more detail.

As shown in FIG. 14, open holes 143 may be further formed in the upper plate 140 at positions corresponding to the insulating spacers 130. Accordingly, the extinguishing chemical liquid generated in the extinguishing sheet 150 may pass through the upper plate 140 through the open hole 143 of the upper plate 140 and reach the insulating spacer 130. In addition, the extinguishing chemical liquid moves along the surface of the insulating spacer 130, and thus faces the case 121 of the battery cell 120, thereby extinguishing and cooling the battery cell 120. In this case, since the extinguishing chemical liquid is sprayed from the extinguishing sheet 150 corresponding to the temperature of the battery cells 120 or higher than the standard, the extinguishing chemical liquid may be sprayed from the top of the battery cell 120 whose temperature is increased. In addition, since the extinguishing chemical liquid is located along the surface of the insulating spacer 130 located before and after the corresponding battery cell 120, the extinguishing and cooling of the corresponding battery cell 120 can be performed together.

Hereinafter, a configuration of an energy storage module according to another embodiment of the present invention will be described.

15 is a perspective view of an energy storage module according to another embodiment of the present invention. 16 is a bottom perspective view of an energy storage module according to another embodiment of the present invention. 17 is a cross-sectional view taken along line E-E in FIG. 15. 18 is a perspective view illustrating a state in which a battery cell and an insulating spacer are disposed on a cover member in an energy storage module according to another embodiment of the present invention.

15 to 18, the energy storage module 200 according to another embodiment of the present invention includes a cover member 210, a battery cell 120, an insulating spacer 230, an upper plate 240, and a fire extinguishing sheet. A configuration of 250 and an upper cover 260 may be included.

Here, the configuration of the cover member 210, the upper plate 240, the fire extinguishing sheet 250, and the upper cover 260 may be formed similar to the energy storage module 100 according to the above-described embodiment. In addition, the configuration of the battery cell 120 may be the same as the energy storage module 100 according to the above-described embodiment. Hereinafter, among the energy storage modules 200, a configuration different from that of the energy storage module 100 will be mainly described.

First, the cover member 210 includes a lower plate 211, an end plate 212, and a side plate 213, through which a space in which the battery cells 120 and the insulating spacers 230 are alternately disposed is provided. Can be equipped. In addition, the cover member 210 may fix the positions of the battery cells 120 and the insulating spacers 230 and protect the battery cells 120 from external impacts. In addition, the lower plate 211 may be further provided with a through hole 211a for discharging the extinguishing chemical solution of the extinguishing sheet 250 and discharging the air that has moved along the outer surface of the insulating spacer 230. The through hole 211a may be located at a position corresponding to the insulating spacer 230.

The insulating spacer 230 is interposed between the battery cells 120 to prevent the battery cells 120 from contacting each other, thereby maintaining electrical independence. The insulating spacer 230 may have a planar size that covers both long side surfaces of the two battery cells 120 whose short sides face each other. That is, one insulating spacer 230 may be interposed between four battery cells 120 disposed so that their long sides face each other. In addition, a predetermined gap is maintained between the insulating spacer 230 and the battery cell 120 to provide a passage for external air or a passage for moving the extinguishing chemical solution so that the battery cell 120 is cooled. Such an insulating spacer 230 may be used by mixing a flame-retardant or non-flammable sheet to prevent flame from spreading and an insulating sheet to prevent heat from spreading when a fire occurs in the battery cell 120, such an insulating spacer The configuration of 230 will be described later.

The upper plate 240 may be coupled to the upper portion of the cover member 210. The upper plate 240 may be coupled to the cover member 210 while covering the upper portion of the battery cell 120.

Meanwhile, the upper plate 240 includes a duct 241 corresponding to the vents 124a formed on the upper surfaces of the plurality of battery cells 120. A plurality of such ducts 241 may be arranged along one direction, for example, a length direction. Accordingly, the gas discharged by operating the vent 124a of the battery cell 120 may move upward along the duct 241 of the upper plate 240. The specific structure and operation of the duct 241 will be described later.

The fire extinguishing sheet 250 is located between the upper plate 240 and the upper cover 260. The fire extinguishing sheet 250 may be mounted on both sides of the duct 241 of the upper plate 240 in the shape of a flat sheet extending along the longitudinal direction and on the lower surface 260b of the upper cover 260. Here, the longitudinal direction may be a direction in which the plurality of ducts 241 of the upper plate 240 extend.

The upper cover 260 is coupled to the upper portion of the upper plate 240. The upper cover 260 may cover the upper plate 240 and the fire extinguishing sheet 250 to protect them from an impact applied from the upper surface 260a of the upper cover 260. In addition, the upper cover 260 may include a discharge hole 261. In addition, the upper cover 260 may further include a protrusion 262 spaced apart from the outer periphery of the discharge hole 261 and protruding downward. The duct 241 may be coupled to the inside of the protrusion 262 of the protrusion 262. The discharge holes 261 may be formed by arranging a plurality of discharge holes 261 along one direction, for example, a length direction of the upper cover 260. In addition, the discharge hole 261 may be formed at a position corresponding to the duct 241 of the upper plate 240. In addition, the discharge hole 261 may also be provided in the form of a hole penetrating between the upper surface and the lower surface so as to be spaced apart from each other like the duct 241. Accordingly, the gas discharged by operating the vent 124a of the battery cell 120 may be discharged to the outside along the duct 241 of the upper plate 240 and the discharge hole 261 of the upper cover 260. have.

In addition, the upper cover 160 may be further provided with a through hole 263 for discharging the extinguishing chemical solution of the extinguishing sheet 250 and discharging the air that has moved along the outer surface of the insulating spacer 230. The through hole 263 may be located at a position corresponding to the insulating spacer 230.

In addition, in the longitudinal direction in which the discharge hole 261 is formed in the upper cover 260, the corresponding region may have a recess 265 having a lower height than other regions. Through this configuration, the gas discharged through the duct 241 and the discharge hole 261 may be collected in the concave portion 265. On the other hand, it is possible to discharge the gas generated in the battery cell early by allowing the collected gas to be discharged to the outside through a separate fan or suction structure.

Hereinafter, the structure and operation of the battery cell 120 and the insulating spacer 130 in the energy storage module according to another embodiment of the present invention will be described.

19A and 19B are perspective and exploded perspective views showing the configuration of an insulating spacer in an energy storage module according to another embodiment of the present invention. 20 is a cross-sectional perspective view taken along line F-F of FIG. 15.

The battery cells 120 may be disposed alternately with the insulating spacer 230 on the upper surface of the lower plate 211 of the cover member 210. In this case, the insulating spacer 230 may have a planar size that covers both long side surfaces of the two battery cells 120 whose short sides are opposite to each other. Here, one insulating spacer 230 may cover both long side surfaces of the two battery cells 120, and the other side may also cover both long side surfaces of the two battery cells 120. That is, the insulating spacer 230 may be interposed between four battery cells 120 disposed so that their long sides face each other.

In addition, the long side surfaces of the battery cells 120 may be spaced apart from the long side surfaces of the battery cells 120 facing each other by a predetermined distance, and an insulating spacer 230 may be interposed therebetween.

Here, the first separation distance, which is the separation distance between the long side surfaces of the battery cells 120 facing each other, may be any one of 3.5mm to 4.5mm. Here, when the first separation distance is less than 3.5 mmm, it is not easy to form an air layer between the insulating spacer 230 and the battery cell 120, and cooling performance may be deteriorated. In addition, when the first separation distance exceeds 4.5mm, it may unnecessarily increase the size of the energy storage module 200.

The insulating spacer 230 prevents the battery cells 120 from contacting each other between the battery cells 120, thereby maintaining electrical independence. In addition, the insulating spacer 230 and the long side surface of the battery cell 120 may be spaced apart by a predetermined distance to form an external air passage. Here, the battery cell 120 may allow the external air passage to be cooled by movable external air.

The insulating spacer 230 may be formed only as a sheet without a separate edge portion configuration. When a fire occurs in the battery cell 120, the insulating spacer 230 may be used by mixing a sheet having flame retardancy or non-combustibility to prevent the fire from spreading and an insulating sheet to prevent heat from spreading. In more detail, the sheet portion 231 includes a first sheet 231a having heat insulating properties and two second sheets having flame retardancy or non-flammability attached to both sides of the first sheet 231a through an adhesive member 231c, respectively. It may include a sheet (231b). Here, the first sheet 231a and the second sheet 231b may have the same size. If the thickness of the insulating spacer 230 does not exceed 50% of the first separation distance, it may be easy to move the extinguishing agent to be described later.

The first sheet 231a is interposed between the second sheets 231b so as to have a predetermined length from the upper and lower ends of the first sheet 231a, so that between the first sheet 231a and the second sheet 231b may be attached. In addition, the adhesive member 231c may have the same width as the width direction of the first sheet 231a and the second sheet 231b. That is, the upper and lower ends of the first sheet 231a may be adhered to the upper and lower ends of the second sheet 231b by the adhesive member 231c.

Here, when the size of the sheet part 231 is two or more times larger than the size in the height direction, the sheet part 231 may be attached to the upper and lower ends with an adhesive member 231c to improve adhesion performance. That is, when the size of the sheet part 231 is twice or more than the size in the height direction, as shown in FIG. 12A, the sheet part 231 is adhered to both ends of the sheet part 131 with adhesive members 131c. Performance may be degraded. The configuration of the insulating spacer 230 may be the same as that of the sheet portion 231 shown in FIG. 12B.

Meanwhile, as mentioned above, when the extinguishing chemical liquid is applied from the upper portion of the insulating spacer 230, it may move downward along the surface of the sheet portion 231. Therefore, the extinguishing chemical liquid comes into contact with the case 121 of the battery cell 120, and thus, the extinguishing of the battery cell 120 as well as the cooling function can be performed. Hereinafter, the movement of the extinguishing chemical and cooling through air will be described in more detail.

As shown in FIG. 20, open holes 243 may be further formed in the upper plate 240 at positions corresponding to the insulating spacers 230. Accordingly, the extinguishing chemical liquid generated in the extinguishing sheet 250 may pass through the upper plate 240 through the open hole 243 of the upper plate 240 and reach the insulating spacer 230. In addition, the extinguishing chemical liquid moves along the surface of the insulating spacer 230 and thus faces the case 121 of the battery cell 120, thereby extinguishing and cooling the battery cell 120. In this case, since the extinguishing chemical liquid is sprayed from the extinguishing sheet 250 corresponding to the temperature of the battery cells 120 or higher than the reference, the extinguishing chemical may be sprayed from the top of the battery cell 120 whose temperature is increased. In addition, since the extinguishing chemical liquid is located along the surface of the insulating spacer 230 located before and after the corresponding battery cell 120, the extinguishing and cooling of the corresponding battery cell 120 can be performed together.

In addition, the upper cover 260 may further include a through hole 263 penetrating between the upper surface and the lower surface at a position corresponding to the open hole 243 of the upper plate 240. That is, the through hole 263 may be provided at a position corresponding to the insulating spacer 230.

In addition, a through hole 211a may be further provided in the lower plate 211 of the cover member 210 at a position corresponding to the insulating spacer 230. That is, the air introduced through the through hole 263 of the upper cover 260 and the open hole 243 of the upper plate 240 moves along the spaced space between the insulating spacer 230 and the battery cell 120 Thus, it may be discharged through the through hole 211a of the lower plate 211. Of course, air can move vice versa. As described above, a flow path for air is formed through the through holes 211a and 263 and the open holes 243, so that cooling efficiency may be improved.

Hereinafter, the composition of the active material of the battery cell 120 used in the energy storage module 100 according to an embodiment of the present invention and the energy storage module 200 according to another embodiment will be described in more detail.

21A and 21B are perspective and cross-sectional views of a battery cell used in an energy storage module according to an embodiment of the present invention.

21A and 21B, the battery cell 120 has a shape in which the electrode assembly 125 is accommodated in the case 121 and the cap plate 124 covers the upper portion of the case 121. In addition, a vent 124a formed to have a thinner thickness compared to other regions may be formed at approximately the center of the cap plate 124. It has been described above that the duct 141 of the upper plate 140 is disposed corresponding to the upper portion of the vent 124a.

In addition, the electrode assembly 125 may be electrically connected to the first electrode terminal 122 and the second electrode terminal 123 on the cap plate 124 through a pair of current collectors 126. Hereinafter, for convenience, the first electrode terminal 122 is described as a negative terminal and the second electrode terminal 123 is described as a positive terminal, but the polarity may be reversed.

The electrode assembly 125 may include a cathode 125a, an anode 125b disposed opposite to the cathode 125a, and a separator 125c disposed between the cathode 125a and the anode 125b, and an electrolyte solution It may be accommodated in the case 121 together with (not shown).

Here, the negative electrode 125a may include a negative electrode current collector, a negative electrode active material layer disposed on the negative electrode current collector, and a negative functional layer disposed on the negative electrode active material layer.

When the negative electrode functional layer including the plate-shaped polyethylene particles is provided, the reaction rate according to the temperature is increased under the same reaction conditions as compared to the case where the spherical polyethylene particles are included, so that the stability improvement effect of the lithium secondary battery may be further improved.

In the case of plate-shaped polyethylene particles before melting, the area covering the pores is located in a thinner and wider shape than the spherical polyethylene particles before melting. When the polyethylene particles melt at a certain temperature or higher to close the ion passage, since the plate-shaped polyethylene particles are larger than the electrode plate area where the spherical polyethylene particles are melted and closed, there is an advantage in that the reaction speed is fast.

That is, when the battery is thermally runaway, the polyethylene particles included in the negative electrode functional layer are melted to close the ion passage, thereby limiting the movement of ions to express a shutdown function, thereby preventing an additional electrochemical reaction.

For example, as shown in FIG. 24, since the plate-shaped polyethylene particles according to an embodiment are located in a thin and wide shape above the pores in the negative electrode functional layer composition, they melt more rapidly during thermal runaway due to thermal/physical shock, thereby allowing the passage of ions. It is excellent in the effect of suppressing.

In general, polyethylene is HDPE (High density polyethylene, density: 0.94 g/cc to 0.965 g/cc), MDPE (Medium density polyethylene, density: 0.925 g/cc to 0.94 g/cc), LDPE (Low density polyethylene), depending on the density. , Density: 0.91 g/cc to 0.925 g/cc), VLDPE (Very low density polyethylene, density: 0.85 g/cc to 0.91 g/cc), etc.

The plate-shaped polyethylene particles may be used alone or in combination of two or more polyethylene polymers such as HDPE, MDPE, and LDPE.

The average particle size (D50) of the plate-shaped polyethylene particles included in the negative functional layer positioned on the negative active material layer may be 1 µm to 8 µm, and specifically 2 µm to 6 µm.

Unless otherwise defined herein, the average particle size (D50) can be measured by a method well known to those skilled in the art, for example, measured with a particle size analyzer, or a TEM photograph or a SEM photograph. It can also be measured from Another method is to measure using a measuring device using dynamic light-scattering, perform data analysis, count the number of particles for each particle size range, and calculate the D50 value from this. Can be easily obtained.

Meanwhile, the ratio of the long axis length to the short axis length of the plate-shaped polyethylene particles may be 1 to 5, specifically 1.1 to 4.5, and, for example, 1.2 to 3.5.

In addition, the thickness of the plate-shaped polyethylene particles may be 0.2um to 4um, specifically, 0.3um to 2.5um, for example, 0.3um to 1.5um.

The polyethylene particles according to the present invention are plate-shaped, as shown in FIG. 23, and have a specific shape different from the spherical polyethylene particles in the aqueous dispersion state shown in FIG. 22, which are general polyethylene particles, and the average particle size of the plate-shaped polyethylene is (D50 ) Can be defined.

The negative electrode functional layer may further include inorganic particles and a binder.

The plate-shaped polyethylene particles and the inorganic particles: the binder may be included in a weight ratio of 80:20 to 99:1, and specifically, may be included in a weight ratio of 85:15 to 97:3.

The plate-shaped polyethylene particles and the inorganic particles: the binder may be included in a weight ratio of 80:20 to 99:1, and specifically, may be included in a weight ratio of 85:15 to 97:3.

When the content of the plate-shaped polyethylene particles and the inorganic particles is within the above range, life characteristics and output characteristics of the battery can be secured.

The inorganic particles are, for example, Al ₂ O ₃ , SiO ₂ , TiO ₂ , SnO ₂ , CeO ₂ , MgO, NiO, CaO, GaO, ZnO, ZrO ₂ , Y ₂ O ₃ , SrTiO ₃ , BaTiO ₃ , Mg (OH) ₂ , boehmite, or a combination thereof may be included, but is not limited thereto. In addition, in addition to the inorganic particles, organic particles including an acrylic compound, an imide compound, an amide compound, or a combination thereof may be further included, but the present invention is not limited thereto.

The inorganic particles may be spherical, plate, cubic, or amorphous. The average particle diameter of the inorganic particles may be about 1 nm to 2500 nm, within the above range, 100 nm to 2000 nm, or 200 nm to 1000 nm, for example, about 300 nm to 800 nm. The average particle diameter of the inorganic particles may be a particle size (D50) at 50% by volume in a cumulative size-distribution curve.

The thickness of the negative electrode functional layer may be 1 µm to 10 µm, and specifically 3 µm to 10 µm.

The ratio of the negative active material layer thickness to the negative functional layer thickness may be 50:1 to 10:1, specifically 30:1 to 10:1.

When the thickness of the negative electrode functional layer is within the above range, thermal stability may be remarkably improved while maintaining excellent lifespan characteristics.

In particular, when the ratio of the thickness of the negative electrode functional layer is within the above range, it is possible to improve thermal safety while minimizing the decrease in energy density.

The negative electrode current collector may be selected from the group consisting of a copper foil, a nickel foil, a stainless steel foil, a titanium foil, a nickel foam, a copper foam, a polymer substrate coated with a conductive metal, and a combination thereof. .

As the negative active material, a material capable of reversibly intercalating/deintercalating lithium ions, a lithium metal, an alloy of lithium metal, a material capable of doping and undoping lithium, or a transition metal oxide may be used.

As a material capable of reversibly intercalating/deintercalating lithium ions, for example, a carbon material, that is, a carbon-based negative active material generally used in lithium secondary batteries may be mentioned. As a representative example of the carbon-based negative active material, crystalline carbon, amorphous carbon, or these may be used together. Examples of the crystalline carbon include graphite such as amorphous, plate-shaped, flake, spherical or fibrous natural graphite or artificial graphite, and examples of the amorphous carbon include soft carbon or hard carbon. carbon), mesophase pitch carbide, and fired coke.

The lithium metal alloy is a group consisting of lithium and Na, K, Rb, Cs, Fr, Be, Mg, Ca, Sr, Si, Sb, Pb, In, Zn, Ba, Ra, Ge, Al and Sn An alloy of a metal selected from may be used.

The lithium-doped and undoped materials include silicon-based materials such as Si, SiOx (0<x<2), and Si-Q alloys (where Q is an alkali metal, alkaline earth metal, group 13 element, group 14 element) , Group 15 element, Group 16 element, transition metal, rare earth element, and an element selected from the group consisting of a combination thereof, and not Si), Si-carbon composite, Sn, SnO2, Sn-R (where R is an alkali metal , Alkaline earth metal, group 13 element, group 14 element, group 15 element, group 16 element, transition metal, rare earth element and combinations thereof, and not Sn), Sn-carbon complex, etc. Alternatively, at least one of these and SiO2 may be mixed and used. The elements Q and R include Mg, Ca, Sr, Ba, Ra, Sc, Y, Ti, Zr, Hf, Rf, V, Nb, Ta, Db, Cr, Mo, W, Sg, Tc, Re, Bh, Fe, Pb, Ru, Os, Hs, Rh, Ir, Pd, Pt, Cu, Ag, Au, Zn, Cd, B, Al, Ga, Sn, In, Ge, P, As, Sb, Bi, S, What is selected from the group consisting of Se, Te, Po, and combinations thereof may be used.

Lithium titanium oxide may be used as the transition metal oxide.

The content of the negative active material in the negative active material layer may be 95% to 99% by weight based on the total weight of the negative active material layer.

The negative active material layer may optionally further include a negative conductive material and a negative binder.

The contents of the negative electrode conductive material and the negative electrode binder may be 1% to 5% by weight, respectively, based on the total weight of the negative electrode active material layer.

The negative electrode conductive material is used to impart conductivity to the negative electrode, and in the configured battery, any material may be used as long as it does not cause chemical change and is an electronic conductive material, such as natural graphite, artificial graphite, carbon black, acetylene black, Carbon-based materials such as ketjen black and carbon fiber; Metal-based materials such as metal powders such as copper, nickel, aluminum, and silver, or metal fibers; Conductive polymers such as polyphenylene derivatives; Alternatively, a conductive material containing a mixture thereof may be used.

The negative electrode binder serves to attach the negative active material particles well to each other and also to the negative active material to the current collector. As the negative electrode binder, a water-insoluble binder, a water-soluble binder, an amphoteric binder (aqueous/water-insoluble binder), or a combination thereof may be used.

As the water-insoluble binder, polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, polymer containing ethylene oxide, polyvinylpyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride , Polyethylene, polypropylene, polyamideimide, polyimide, or combinations thereof.

Examples of the water-soluble binder include styrene-butadiene rubber, acrylated styrene-butadiene rubber, polyvinyl alcohol, sodium polyacrylate, propylene and C2-C8 olefin copolymer, (meth)acrylic acid and (meth)acrylate alkyl ester. Copolymers or combinations thereof.

Examples of the amphoteric binder include acrylated styrene rubber.

When a water-soluble binder is used as the negative electrode binder, a cellulose-based compound capable of imparting viscosity may be further included as a thickener. As the cellulose-based compound, one or more types of carboxymethyl cellulose, hydroxypropylmethyl cellulose, methyl cellulose, or alkali metal salts thereof may be mixed and used. Na, K or Li may be used as the alkali metal. The content of the thickener may be 0.1 parts by weight to 3 parts by weight based on 100 parts by weight of the negative active material.

The positive electrode of the lithium secondary battery according to an embodiment of the present invention includes a first positive electrode active material including at least one of a composite oxide of lithium and a metal selected from cobalt, manganese, nickel, and combinations thereof, and the following Formula 1 A positive electrode active material layer including a second positive electrode active material containing the compound represented by may be provided.

A lithium secondary battery according to an embodiment of the present invention simultaneously includes a negative electrode functional layer disposed on a negative electrode and a positive electrode active material layer including the first positive electrode active material and the second positive electrode active material. It has the effect of lowering the rate of ascent and helping to completely close the passage of ions by melting the plate-shaped polyethylene particles. In the case of a secondary battery in which the positive electrode is not combined according to an embodiment, the ion passage cannot be completely closed when heat rises due to thermal/physical shock (FIG. 29), but according to an embodiment, a negative electrode functional layer is included. In the case of a secondary battery including a negative electrode and a positive electrode at the same time, when heat increases due to thermal/physical shock, the ion passage can be relatively completely closed, thereby maximizing safety (FIG. 30).

Meanwhile, the positive electrode 125b may include a positive electrode current collector and a positive electrode active material layer positioned on the positive electrode current collector.

The positive electrode active material layer includes a first positive electrode active material containing at least one of a complex oxide of lithium and a metal selected from cobalt, manganese, nickel, and combinations thereof, and a second positive electrode active material containing a compound represented by the following formula (1). It may include a positive electrode active material.

In addition, the positive electrode active material layer may further include a positive electrode functional layer positioned on the positive electrode active material layer.

The first positive electrode active material may be at least one of a composite oxide of lithium and a metal selected from cobalt, manganese, nickel, and combinations thereof.

A specific example of the first positive electrode active material may be a compound represented by any one of the following formulas.

Li _a A _1-b X _b D ₂ (0.90≦a≦1.8, 0≦b≦0.5); Li _a A _1-b X _b O _2-c D _c (0.90 <a <1.8, 0 <b <0.5, 0 <c <0.05); Li _a E _1-b X _b O _2-c D _c (0≦b≦0.5, 0≦c≦0.05); Li _a E _2-b X _b O _4-c D _c (0≦b≦0.5, 0≦c≦0.05); Li _a Ni _1-bc Co _b X _c D _α (0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.5, 0 <α ≤ 2); Li _a Ni _1-bc Co _b X _c O _2-α T _α (0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 <α <2); Li _a Ni _1-bc Co _b X _c O _2-α T ₂ (0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 <α <2); Li _a Ni _1-bc Mn _b X _c D _α (0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 <α ≤ 2); Li _a Ni _1-bc Mn _b X _c O _2-α T _α (0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 <α <2); Li _a Ni _1-bc Mn _b X _c O _{2 -α} T ₂ (0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 <α <2); Li _a Ni _b E _c G _d O ₂ (0.90≦a≦1.8, 0≦b≦0.9, 0≦c≦0.5, 0.001≦d≦0.1); Li _a Ni _b Co _c Mn _d G _e O ₂ (0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.9, 0 ≤ c ≤ 0.5, 0 ≤ d ≤ 0.5, 0.001 ≤ e ≤ 0.1); Li _a NiG _b O ₂ (0.90≦a≦1.8, 0.001≦b≦0.1); Li _a CoG _b O ₂ (0.90≦a≦1.8, 0.001≦b≦0.1); Li _a Mn _1-b G _b O ₂ (0.90≦a≦1.8, 0.001≦b≦0.1); Li _a Mn ₂ G _b O ₄ (0.90≦a≦1.8, 0.001≦b≦0.1); Li _a Mn _1-g G _g PO ₄ (0.90≦a≦1.8, 0≦g≦0.5); QO ₂ ; QS ₂ ; LiQS ₂ ; V ₂ O ₅ ; LiV ₂ O ₅ ; LiZO ₂ ; LiNiVO ₄ ; Li _(3-f) J ₂ (PO ₄ ) ₃ (0≦f≦2); Li _(3-f) Fe ₂ (PO ₄ ) ₃ (0≦f≦2); Li _a FePO ₄ (0.90 ≤ a ≤ 1.8)

In the above formula, A is selected from the group consisting of Ni, Co, Mn, and combinations thereof; X is selected from the group consisting of Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements, and combinations thereof; D is selected from the group consisting of O, F, S, P, and combinations thereof; E is selected from the group consisting of Co, Mn, and combinations thereof; T is selected from the group consisting of F, S, P, and combinations thereof; G is selected from the group consisting of Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, and combinations thereof; Q is selected from the group consisting of Ti, Mo, Mn, and combinations thereof; Z is selected from the group consisting of Cr, V, Fe, Sc, Y, and combinations thereof; J is selected from the group consisting of V, Cr, Mn, Co, Ni, Cu, and combinations thereof.

Of course, one having a coating layer on the surface of the compound may be used, or a mixture of the compound and a compound having a coating layer may be used. The coating layer contains at least one coating element compound selected from the group consisting of oxides of coating elements, hydroxides of coating elements, oxyhydroxides of coating elements, oxycarbonates of coating elements, and hydroxycarbonates of coating elements. I can. The compound constituting these coating layers may be amorphous or crystalline. As a coating element included in the coating layer, Mg, Al, Co, K, Na, Ca, Si, Ti, V, Sn, Ge, Ga, B, As, Zr, or a mixture thereof may be used. The coating layer formation process may be any coating method as long as the compound can be coated by a method that does not adversely affect the physical properties of the positive electrode active material by using these elements (e.g., spray coating, dipping method, etc.). Since the content can be well understood by those engaged in the relevant field, detailed description will be omitted.

In one embodiment, the first positive electrode active material and the second positive electrode active material may be included in a weight ratio of 97:3 to 80:20, for example, in a weight ratio of 95:5 to 85:15.

The content of the first positive electrode active material is 70% to 99% by weight, more specifically, 85% to 99% by weight, 87% to 95% by weight, or 90% to 98% by weight based on the total amount of the positive electrode active material layer. I can. When the content of the first positive active material satisfies the above range, it is possible to improve safety without reducing the capacity.

The second positive electrode active material may include, _{for example, LiFePO 4.}

The content of the second positive electrode active material is 1% to 15% by weight, more specifically, 2% to 15% by weight, 2% to 12% by weight, or 2% to 10% by weight based on the total amount of the positive electrode active material layer. Can be When the content of the second positive electrode active material satisfies the above range, safety may be improved without reducing the capacity.

Aluminum, nickel, or the like may be used as the positive electrode current collector, but is not limited thereto.

The positive electrode active material layer may optionally further include a positive electrode conductive material and a positive electrode binder.

The contents of the positive electrode conductive material and the positive electrode binder may be 1% to 5% by weight, respectively, based on the total weight of the positive electrode active material layer.

The positive electrode conductive material is used to impart conductivity to the positive electrode, and the type of the positive electrode conductive material is the same as that of the aforementioned negative electrode conductive material.

The positive electrode binder attaches the positive electrode active material particles well to each other and also serves to attach the positive electrode active material well to the current collector, and representative examples thereof include polyvinyl alcohol, carboxymethylcellulose, hydroxypropylcellulose, diacetylcellulose, and poly(polyvinylcellulose). Vinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, polymer containing ethylene oxide, polyvinylpyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, styrene -Butadiene rubber, acrylated styrene-butadiene rubber, epoxy resin, nylon, etc. may be used, but the present invention is not limited thereto.

The electrolyte solution contains a non-aqueous organic solvent and a lithium salt.

The non-aqueous organic solvent serves as a medium through which ions involved in the electrochemical reaction of the battery can move. As the non-aqueous organic solvent, a carbonate-based, ester-based, ether-based, ketone-based, alcohol-based, or aprotic solvent may be used. As the carbonate-based solvent, dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), methylpropyl carbonate (MPC), ethylpropyl carbonate (EPC), methyl ethyl carbonate (MEC), ethylene carbonate ( EC), propylene carbonate (PC), butylene carbonate (BC), and the like may be used, and as the ester solvent, methyl acetate, ethyl acetate, n-propyl acetate, dimethyl acetate, methyl propionate, ethyl propionate , γ-butyrolactone, decanolide, valerolactone, mevalonolactone, caprolactone, and the like may be used. Dibutyl ether, tetraglyme, diglyme, dimethoxyethane, 2-methyltetrahydrofuran, tetrahydrofuran, etc. may be used as the ether solvent, and cyclohexanone may be used as the ketone solvent. have. In addition, ethyl alcohol, isopropyl alcohol, etc. may be used as the alcohol-based solvent, and R-CN (R is a linear, branched, or cyclic hydrocarbon group having 2 to 20 carbon atoms) as the aprotic solvent. , A double bonded aromatic ring or an ether bond), such as nitriles, amides such as dimethylformamide, dioxolanes such as 1,3-dioxolane, sulfolanes, and the like may be used. .

The non-aqueous organic solvent can be used alone or in combination of one or more, and the mixing ratio in the case of using one or more mixtures can be appropriately adjusted according to the desired battery performance, which will be widely understood by those in the field. I can.

In addition, in the case of a carbonate-based solvent, it is preferable to use a mixture of a cyclic carbonate and a chain carbonate. In this case, when the cyclic carbonate and the chain carbonate are mixed in a volume ratio of 1:1 to 1:9, the electrolyte may exhibit excellent performance.

In addition, in the case of a carbonate-based solvent, it is preferable to use a mixture of a cyclic carbonate and a chain carbonate. In this case, when the cyclic carbonate and the chain carbonate are mixed in a volume ratio of 1:1 to 1:9, the electrolyte may exhibit excellent performance.

As the aromatic hydrocarbon-based organic solvent, an aromatic hydrocarbon-based compound represented by the following formula (2) may be used.

[Formula 2]

In Formula 2, R ₁ to R ₆ are the same as or different from each other and are selected from the group consisting of hydrogen, halogen, an alkyl group having 1 to 10 carbon atoms, a haloalkyl group, and combinations thereof.

Specific examples of the aromatic hydrocarbon-based organic solvent include benzene, fluorobenzene, 1,2-difluorobenzene, 1,3-difluorobenzene, 1,4-difluorobenzene, 1,2,3-trifluoro Lobenzene, 1,2,4-trifluorobenzene, chlorobenzene, 1,2-dichlorobenzene, 1,3-dichlorobenzene, 1,4-dichlorobenzene, 1,2,3-trichlorobenzene, 1, 2,4-trichlorobenzene, iodobenzene, 1,2-diiodobenzene, 1,3-diaiodobenzene, 1,4-diaiodobenzene, 1,2,3-triiodobenzene, 1,2 ,4-triiodobenzene, toluene, fluorotoluene, 2,3-difluorotoluene, 2,4-difluorotoluene, 2,5-difluorotoluene, 2,3,4-trifluoro Toluene, 2,3,5-trifluorotoluene, chlorotoluene, 2,3-dichlorotoluene, 2,4-dichlorotoluene, 2,5-dichlorotoluene, 2,3,4-trichlorotoluene, 2,3 ,5-trichlorotoluene, iodotoluene, 2,3-diaiodotoluene, 2,4-diaiodotoluene, 2,5-diaiodotoluene, 2,3,4-triiodotoluene, 2,3, It is selected from the group consisting of 5-triiodotoluene, xylene, and combinations thereof.

The non-aqueous electrolyte may further include vinylene carbonate or an ethylene carbonate-based compound represented by the following Formula 3 in order to improve battery life.

[Formula 3]

In Formula 3, R ₇ and R ₈ are the same as or different from each other, and are selected from the group consisting of hydrogen, a halogen group, a cyano group (CN), a nitro group (NO ₂ ), and a fluorinated alkyl group having 1 to 5 carbon atoms, wherein At least one of R ₇ and R ₈ is selected from the group consisting of a halogen group, a cyano group (CN), a nitro group (NO ₂ ) and a fluorinated alkyl group having 1 to 5 carbon atoms, provided that both _{R 7} and R _{8 are hydrogen} no.

Representative examples of ethylene carbonate-based compounds include difluoro ethylene carbonate, chloroethylene carbonate, dichloroethylene carbonate, bromoethylene carbonate, dibromoethylene carbonate, nitroethylene carbonate, cyanoethylene carbonate or fluoroethylene carbonate. have. In the case of further use of such a life-improving additive, the amount of the additive may be appropriately adjusted.

Lithium salt is a material that is dissolved in an organic solvent and acts as a source of lithium ions in the battery, enabling basic lithium secondary battery operation, and promoting the movement of lithium ions between the positive electrode and the negative electrode. Representative examples of such lithium salts are LiPF ₆ , LiBF ₄ , LiSbF ₆ , LiAsF ₆ , LiN(SO ₂ C ₂ F ₅ ) ₂ , Li(CF ₃ SO ₂ ) ₂ N, LiN(SO ₃ C ₂ F ₅ ) ₂ , LiC ₄ F ₉ SO ₃ , LiClO ₄ , LiAlO ₂ , LiAlCl ₄ , LiN(C _x F _2x+1 SO ₂ )(C _y F _2y+1 SO ₂ ) (where x and y are natural numbers), LiCl, LiI and LiB(C ₂ O ₄ ) ₂ (lithium bis(oxalato) borate; LiBOB) contains one or more selected from the group consisting of as a supporting electrolytic salt. Concentration of lithium salt It is recommended to use within the range of 0.1 to 2.0 M. When the concentration of the lithium salt is included in the above range, the electrolyte has an appropriate conductivity and viscosity, so that excellent electrolyte performance can be exhibited, and lithium ions can move effectively.

Meanwhile, as described above, a separator 125c may be disposed between the anode 125a and the cathode 125b. The separator 125c may be selected from, for example, glass fiber, polyester, polyethylene, polypropylene, polytetrafluoroethylene, or a combination thereof, and may be in the form of a nonwoven fabric or a woven fabric.

For example, a polyolefin-based polymer separator such as polyethylene, polypropylene, etc. may be mainly used for a lithium secondary battery, and a separator coated with a composition containing a ceramic component or a polymer material may be used to secure heat resistance or mechanical strength. It can be used in a single-layer or multi-layer structure.

Hereinafter, aspects of the present invention described above through examples will be described in more detail. However, the following examples are for illustrative purposes only and do not limit the scope of the present invention.

(Manufacture of lithium secondary battery)

Example 1: A battery LCO/LFP containing plate-shaped 2 μm PE particles was mixed in a weight ratio of 9:1 to 95% by weight of a positive electrode active material, 3% by weight of a polyvinylidene fluoride binder, and 2% by weight of a Ketjen Black conductive material. -Methylpyrrolidone was mixed in a solvent to prepare a positive electrode active material slurry. The positive electrode active material slurry was coated on both surfaces of an aluminum current collector, dried, and rolled to prepare a positive electrode having a positive electrode active material layer formed thereon.

98% by weight of graphite, 0.8% by weight of carboxymethyl cellulose, and 1.2% by weight of styrene-butadiene rubber were mixed in pure water to prepare a negative active material slurry. The negative active material slurry was coated on both sides of a copper current collector, dried, and rolled to prepare a negative electrode having a negative active material layer formed thereon.

Plate-shaped 2㎛ PE particles (long axis length / short axis length = about 2, thickness = about 0.6㎛) 48% by weight, alumina (average particle diameter (D50) = 0.7㎛) 47% by weight and acrylated styrene rubber binder 5% by weight % Was mixed with an alcohol-based solvent to prepare a PE/alumina slurry.

The PE/alumina slurry was coated on both sides, dried, and rolled on the surface of the negative electrode to prepare a negative electrode having a coating layer including plate-shaped PE particles.

The positive electrode, the separator composed of the PE/PP multilayer substrate, and the negative electrode having a coating layer including the plate-shaped PE particles were sequentially stacked to prepare an electrode assembly having the structure as shown in FIG.

Example 2: A battery containing plate-shaped 4 μm PE particles

A secondary battery was manufactured in the same manner as in Example 1, except that a negative electrode was prepared using 4 μm plate-shaped PE particles (long axis length/short axis length= about 2.4, thickness= about 0.6 μm).

Example 3: A battery containing plate-shaped 6 μm PE particles

A secondary battery was manufactured in the same manner as in Example 1, except that a negative electrode was manufactured using 6 μm plate-shaped PE particles (long axis length/short axis length= about 2.4, thickness= about 0.6 μm).

Comparative Example: Battery Containing Spherical PE Particles

A secondary battery was manufactured in the same manner as in Example 1, except that a negative electrode was prepared using a dispersion obtained by dispersing 4 μm spherical PE particles in an alcohol-based solvent instead of plate-shaped 2 μm PE particles.

(Evaluation example)

1. Evaluation of the increase rate of the resistance of the electrode plate

A negative electrode having a coating layer including the plate-shaped PE particles according to Example 1, a separator composed of a PE/PP multilayer substrate, and a negative electrode having a coating layer including the plate-shaped PE particles according to Example 1 are sequentially stacked, and 1M LiBF ₄ A coin symmetric battery as shown in FIG. 28 was manufactured by injecting an electrolyte solution dissolved in propylene carbonate.

28 is a schematic diagram of a coin symmetric battery manufactured to evaluate the increase rate of the resistance of the electrode plate.

After mounting the prepared coin symmetric battery with a temperature sensor and a resistance meter, the evaluation is started by putting it in a temperature variable chamber. 26 shows the results of evaluating the rate of increase in resistance of the electrode plate according to the temperature by measuring the temperature and resistance change of the coin-symmetric battery while increasing the temperature at a rate of 10°C/min.

26 is a graph evaluating the rate of increase in resistance of an electrode plate according to temperature.

Referring to FIG. 26, it can be seen that at a high temperature of 120° C. or higher, the increase rate of the electrode plate resistance of the examples compared to the comparative example is significantly increased.

From this, in the case of the battery including the electrode composition according to an embodiment, it can be expected that the shut-down function will be expressed early by effectively suppressing the passage of ions during thermal runaway due to thermal/physical shock.

2. Evaluation of cycle life characteristics

The lithium secondary battery prepared in Examples 1 to 3 was charged at a rate of 4.4V at 0.5C/0.5C and then discharged until it reached 3.0V, and the cell capacity reduction rate was measured after completion of 150 cycles, and the results are shown in FIG. I got it. In the 51 cycle and 101 cycle, the recovery capacity was evaluated by charging 4.4V at a rate of 0.2C/0.2C and discharging 3.0V.

27 is a graph evaluating capacity retention rates for 150 cycles of lithium secondary batteries according to Examples 1 to 3;

Referring to FIG. 27, it can be seen that even after 150 cycles, the capacity retention rate is excellent.

As a result, the rechargeable lithium battery according to an exemplary embodiment can effectively express a shutdown function while maintaining excellent battery characteristics.

What has been described above is only one embodiment for implementing the secondary battery according to the present invention, and the present invention is not limited to the above embodiment, and departs from the gist of the present invention as claimed in the following claims. Without it, anyone of ordinary skill in the field to which the present invention pertains will have the technical spirit of the present invention to the extent that various modifications can be implemented.

100, 200; Energy storage modules 110 and 210; Cover plate
120; Battery cell 230; Insulation spacer
131; Seat portion 132; Border
140, 240; Top plates 141, 241; duct
143, 243; Chemical hole 150, 250; Fire extinguishing sheet
160, 260; Top cover

Claims (17)

A plurality of battery cells arranged along the length direction such that the long sides face each other;
A plurality of insulating spacers interposed between long side surfaces of the plurality of battery cells;
A cover plate having an accommodation space therein and accommodating the plurality of battery cells and the plurality of insulating spacers;
A duct coupled to an upper portion of the cover plate and formed at positions corresponding to vents of the plurality of battery cells, and an upper plate having a chemical solution hole formed at a position corresponding to the insulating spacer;
An upper cover coupled to an upper portion of the upper plate and including a discharge hole at a position corresponding to the duct; And
It is located between the upper cover and the upper plate, and comprises a fire extinguishing sheet for spraying a fire extinguishing agent at a predetermined temperature or higher,
The insulating spacer is an energy storage module, characterized in that a first sheet having flame retardancy or non-flammability and a second sheet having heat insulating properties are attached to both surfaces of the first sheet through an adhesive member, respectively. The method of claim 1,
The first sheet is a ceramic paper, and the second sheet is an energy storage module, characterized in that the MICA. The method of claim 2,
The first sheet is an energy storage module, characterized in that the ceramic fiber containing an alkaline earth metal. The method of claim 1,
The plurality of battery cells are spaced apart from each other by a first separation distance between opposite long sides,
The energy storage module, characterized in that the thickness of the insulating spacer is less than 50% of the first separation distance. The method of claim 1,
The energy storage module, wherein the extinguishing agent sprayed from the extinguishing sheet is applied to a space spaced apart from the insulating spacer and the battery cell through the chemical solution hole, and contacts the long side surface of the battery cell. The method of claim 1,
The insulating spacer has a size in the width direction smaller than twice the size in the height direction,
The energy storage module, wherein the first sheet and the second sheet include a sheet portion having both end portions bonded to each other by an adhesive member. The method of claim 6,
The insulating spacer further comprises an edge portion of a plastic material formed by insert injection so as to surround the edge of the seat portion. The method of claim 7,
The width of the edge portion is an energy storage module, characterized in that any one of 3mm to 6mm. The method of claim 6,
The insulating spacer is an energy storage module, wherein one side faces a long side surface of one battery cell, and the other side faces a long side surface of another battery cell. The method of claim 6,
The first sheet and the second sheet are spaced apart from each other at a central portion, the energy storage module, characterized in that provided with an air passage through which air can be moved. The method of claim 1,
The insulating spacer has a size in the width direction greater than twice the size in the height direction,
An energy storage module, wherein a predetermined region of the first sheet and the second sheet is adhered from upper and lower ends by an adhesive member. The method of claim 10,
The insulating spacer is an energy storage module, characterized in that one side faces the long side faces of the two battery cells, and the other face faces the long side faces of the other two battery cells. The method of claim 1,
The battery cell is
A negative electrode including a negative electrode current collector, a negative electrode active material layer disposed on the negative electrode current collector, and a negative functional layer disposed on the negative electrode active material layer; And
A positive electrode current collector, and a positive electrode including a positive electrode active material layer positioned on the positive electrode current collector,
The negative electrode functional layer includes plate-shaped polyethylene particles,
The positive electrode active material layer includes a first positive electrode active material containing at least one of a composite oxide of lithium and a metal selected from cobalt, manganese, nickel, and combinations thereof, and a first positive electrode active material containing a compound represented by the following formula (1). 2 Energy storage module including a positive electrode active material.
[Formula 1]
Li _a Fe ₁ - _x M _x PO ₄
In Formula 1, 0.90 ≤ a ≤ 1.8, 0 ≤ x ≤ 0.7, M is Mg, Co, Ni or
A combination of these. The method of claim 11,
The energy storage module having an average particle size (D50) of 1 μm to 8 μm of the plate-shaped polyethylene particles. The method of claim 13,
The energy storage module having an average particle size (D50) of 1 μm to 8 μm of the plate-shaped polyethylene particles. The method of claim 13,
The thickness of the plate-shaped polyethylene particles is 0.2 ㎛ to 4 ㎛ energy storage module. The method of claim 13,
The energy storage module wherein the first positive electrode active material and the second positive electrode active material are included in a weight ratio of 97:3 to 80:20.

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