KR20180054482A - Battery Pack with Improved Cooling Efficiency and Durability against External Impact - Google Patents

Abstract

The present invention provides a battery pack. The battery pack includes: battery cells; first housings having an internal hollow structure so as to surround the remaining outer surfaces of the battery cells except upper and lower ends where electrode terminals are formed wherein the battery cells are independently mounted on the first housings; a bus bar assembly electrically connecting the battery cells mounted on the first housings; a second housing configured to receive both the battery cells and the bus bar assembly mounted on the first housings; and a protection circuit part for controlling the charge/discharge voltage or current of the battery pack.

Description

[0001] The present invention relates to a battery pack having improved durability and cooling efficiency against impact, and a battery pack having improved cooling efficiency and durability against external impact.

The present invention relates to a battery pack having improved durability against impact and cooling efficiency.

As technology development and demand for mobile devices increase, the demand for secondary batteries as energy sources is rapidly increasing.

The secondary battery may be used in the form of a single battery cell or in the form of a battery pack in which a plurality of battery cells are electrically connected to each other depending on the type of the external device used. For example, a small device such as a cellular phone can operate for a predetermined time with the output and the capacity of one battery cell, while a medium size device such as a notebook computer, a portable DVD, a small PC, an electric vehicle, Or large devices require the use of battery packs in terms of output and capacity issues.

The battery pack is manufactured by assembling a cooling device, various circuits, a protective case, and the like in a battery cell assembly in which a plurality of battery cells are arranged in series and / or in parallel.

When a rectangular or pouch-shaped battery cell is used as the battery cell, it is possible to easily manufacture the battery cell by connecting the electrode terminals with a connecting member such as a bus bar after stacking the large-sized battery cells facing each other. Therefore, when a three-dimensional battery pack having a hexahedral structure is manufactured, a prismatic or pouch-shaped battery cell is advantageous as a unit cell.

On the other hand, the cylindrical battery cell generally has a larger capacitance than the prismatic type and pouch type battery, but the arrangement of the cylindrical battery in the laminated structure is not easy due to the external characteristics of the cylindrical battery. However, when the shape of the battery pack as a whole is a linear or plate-like structure, there is a structural advantage over the square or pouch type.

Therefore, in the case of a notebook computer, a portable DVD, a small-sized PC, etc., a battery pack composed of a plurality of cylindrical batteries is widely used, and in particular, is widely applied as a power source for a medium or large-

1 is a schematic view of a conventional battery pack including cylindrical battery cells.

Referring to FIG. 1, the battery pack 10 has a structure in which a plurality of battery cells 1 are mounted on a bus bar assembly including a connection member 3 and a cell frame 2.

However, the battery pack 10 having such a structure includes the following technical problems.

First, since the battery cells are formed in a structure in which they are in contact with each other, since the cooling air and the surface of the battery cell can be heat-exchanged with each other, It is low point.

In the case of a battery pack, heat is inevitably generated in repeated charging and discharging processes. Such a heat rapidly induces a reaction between the electrolyte and the electrodes in the battery cell, resulting in deterioration of the cell performance, changes in battery cell volume and shape due to gas, And safety problems such as explosion can be caused.

Second, since the outer surface of the battery cells is exposed, an external impact or vibration is directly applied to each of the battery cells.

Particularly, impacts and vibrations in the state where the battery cells are in contact with each other act as a direct cause for causing deformation and breakage of the battery cell, because the battery cells contacting each other cause the external forces to transfer to each other. A broken battery cell may cause ignition and explosion, which may become another cause of safety.

Therefore, there is a high need for techniques for solving the above-described technical problems.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and the technical problems required from the past.

Specifically, it is an object of the present invention to provide a battery pack having a structure including a first housing in which battery cells are independently mounted, and a second housing that encloses the battery cells and the first housing thus mounted, And to provide a battery pack having excellent cooling efficiency while improving durability.

According to an aspect of the present invention, there is provided a battery pack,

A plurality of battery cells each having a cylindrical shape and each having an electrode terminal formed at an upper end and a lower end of the cylinder;

The first and second housings being formed in an inner hollow structure so as to enclose the remaining outer surfaces of the battery cells except the upper and lower ends where the electrode terminals are formed;

A bus bar assembly electrically connecting the battery cells mounted on the first housings;

A second housing configured to accommodate both the battery cells and the bus bar assembly mounted on the first housings; And

A protection circuit part for controlling charge / discharge voltage or current of the battery pack;

And a control unit.

That is, the battery pack according to the present invention has a structure in which the battery pack is mounted to one first housing per battery cell, and the battery cells thus mounted are double-packaged with the second housing, It is possible to prevent the battery cell from being directly applied to the cells, thereby preventing deformation and breakage of each of the battery cells, thereby further improving safety.

Particularly, the entire outer surface of the battery cell except for the electrode terminal portion is sealed from the outside by the first housing. By absorbing or relaxing the external force directly applied to the outer surface of the battery cell by the first housing, It is possible to prevent breakage and deformation of the semiconductor device.

In addition, the battery pack according to the present invention has a structure in which the battery cells are spaced apart from each other by a predetermined distance through a special structure of the first housing described below, so that the battery cells contacting with each other do not transfer external force to each other It is possible to improve the cooling efficiency by smoothly circulating the air while having improved stability against external impact.

In one specific example for this purpose, the battery pack has a connecting portion formed between adjacent first housings;

And the first housings may be connected to each other with a connection portion therebetween.

The connecting portion may be a structure in which the connecting portions are integrally formed with the first housings so as to allow the air to flow between the first housings adjacent to each other while being spaced apart from each other by a predetermined distance. So as to form air vents through which air flows.

In other words, the battery pack according to the present invention has the first housings spaced apart from each other by a predetermined distance in a state where the first housings are connected to the connecting portion, so that the air can be circulated through the spaces where the connecting portions are spaced apart, The first housings are prevented from interfering with each other, so that a direct shock applied to the battery cell when the external impact is applied can be greatly alleviated through the plurality of first housings and the connecting portions.

In the present invention, the predetermined distance set by the connecting portion may be 10% to 30% of the diameter of the battery cell.

It is difficult to expect the improvement of the cooling efficiency as intended by the present invention and the battery cells are spaced apart from each other at a distance exceeding the maximum value of the range Since it is difficult to design the battery pack with high directivity because it is mounted on the second housing, it is not preferable.

The first housing may be an integral member which itself is a unitary member.

In this structure, the first housing can be manufactured as one unit member by injection molding.

Alternatively, a structure in which two units of the members are mutually engaged to form the first housing may be included in the scope of the present invention.

In this case, the two unit members are each a hollow structure having an inner surface shape corresponding to the outer shape of the battery cell except for the electrode terminal portion, respectively; A connection part may be formed on at least one of the two unit members.

Further, the two unit members may include locking means for engaging against each other, and the locking means may be, for example, a male and female locking structure, a ring locking structure, and the like, but is not limited thereto.

In one specific example, the outer surface of the first housing may be provided with a plurality of beads in a direction corresponding to the longitudinal direction thereof.

The beads can induce a flow of air flowing along an outer surface of the first housing between electrode terminals formed at both ends of the battery cell, and heat conduction from the battery cell can be dissipated to the outside.

That is, in the present invention, the first housing is structured such that the air flows to the outer surface of the first housing, so that the cooling of the battery cell can be maximized.

In addition, the beads form an air flow inducing path for guiding a flow of air flowing along an outer surface of the first housing between electrode terminals formed at both ends of the battery cell.

To this end, the first housing may be made of a material having high thermal conductivity, and more specifically, it may be made of a thermally conductive polymer or a thermally conductive metal.

The thermally conductive polymer may be, for example, polybutylene terephthalate (PBT), polytetrafluorethylene (PTFE), polyimide, etc. In some cases, the thermally conductive polymer may be a composite in which particles such as graphite, aluminum, have.

The thermally conductive metal may be a single metal selected from aluminum, magnesium, copper, nickel, zinc, lead, and iron, or two or more kinds of alloy materials, but is not limited thereto.

The beads may be arranged along the outer diameter of the first housing with a predetermined distance apart.

Although the number of the beads is not particularly limited, for example, four beads are arranged along the outer diameter of the first housing, and the beads adjacent to each other are arranged on the outer surface of the first housing at an angle of 90 degrees. .

In this structure, a structure in which adjacent beads are formed at an angle of 45 degrees is possible, and the beads may be formed regularly in a vertical section of the first housing at left and right and up and down symmetrical positions.

Further, the beads may be heat-dissipating fins for heat-exchanging with gas refrigerant flowing between the beads under the condition that the heat of the battery cells mounted on the first housing is conducted. For this structure, May be 100% to 500% of the width.

In this structure, the heat diffusion easily progresses between the closely adjacent beads, so that the beads can function as the heat radiating fin.

Meanwhile, the second housing may include: a mounting part having one side opened to house the battery cells, the protection circuit part, and the bus bar assembly installed in the first housing; And

A cover mounted on an open side of the mounting portion to seal an open side of the mounting portion; . ≪ / RTI >

The mounting portion is formed with a slot for mounting a protection circuit to be slidably mounted on the mounting portion, and a partition for partitioning the mounting portion of the battery cell mounted on the slot and the first housing may be mounted on the mounting portion.

The partition may have a concave-convex structure including a concave portion and a convex portion on a vertical section in order to absorb the impact more flexibly with respect to an external force.

Also, due to the concavo-convex structure, the flow of air can be swirled and flow at a higher speed, and the cooling efficiency of the battery pack can be increased accordingly.

The second housing may include a first slit part formed at one side of the mounting part and having a plurality of slits for introducing air into the mounting part and discharging air to the outside;

A second slit portion formed at one side of the cover with a plurality of slits for air inflow into the cover and air exhaust to the outside; And a handle for gripping the battery pack; Further comprising:

A first air discharge path through which air is discharged to the second slit portion when air flows in the first slit portion or a second air discharge path through which air is discharged from the second slit portion when air flows in the second slit portion, Thereby forming an air discharge path.

In addition, the handle may have a hollow structure inside, and one or more holes may be formed in the outside so that the air introduced from the first slit portion or the second slit portion is discharged to the outside through the handle. .

The present invention also provides a device that uses the battery pack as a power source, such as, but not limited to, a wireless cleaner, a power tool, an electric bicycle, and an unmanned aerial vehicle.

The battery cell defined in the present invention is a lithium-ion secondary battery, a lithium-polymer secondary battery, or a lithium-ion polymer having a high energy density, a discharge voltage, polymer secondary battery, and the like.

Generally, a lithium secondary battery refers to a battery composed of a positive electrode, a negative electrode, a separation membrane, and a lithium salt-containing non-aqueous electrolyte, which are the configurations of the prior electrode assembly.

The positive electrode is prepared, for example, by coating a mixture of a positive electrode active material, a conductive material and a binder on a positive electrode current collector and / or an extended current collector, and then drying the resultant. Optionally, do.

The cathode current collector and / or the elongated current collector are generally made to have a thickness of 3 to 500 micrometers. The positive electrode current collector and the elongate current collector are not particularly limited as long as they have high conductivity without causing a chemical change in the battery, and examples thereof include stainless steel, aluminum, nickel, titanium, A surface treated with carbon, nickel, titanium, or silver on the surface of stainless steel may be used. The anode current collector and the elongate current collector may have various shapes such as a film, a sheet, a foil, a net, a porous body, a foam, a nonwoven fabric, or the like by forming fine irregularities on the surface thereof to increase the adhesive force of the cathode active material.

The cathode active material may be a layered compound such as lithium cobalt oxide (LiCoO2) or lithium nickel oxide (LiNiO2), or a compound substituted with one or more transition metals; Lithium manganese oxides such as Li1 + xMn2-xO4 (where x is 0 to 0.33), LiMnO3, LiMn2O3, LiMnO2 and the like; Lithium copper oxide (Li2CuO2); Vanadium oxides such as LiV3O8, LiFe3O4, V2O5, and Cu2V2O7; A Ni-site type lithium nickel oxide represented by the formula LiNi1-xMxO2 (where M = Co, Mn, Al, Cu, Fe, Mg, B or Ga and x = 0.01 to 0.3); Is represented by the formula LiMn2-xMxO2 wherein M = Co, Ni, Fe, Cr, Zn or Ta and x = 0.01 to 0.1 or Li2Mn3MO8 where M = Fe, Co, Ni, Lithium manganese complex oxide; LiMn2O4 in which a part of Li in the formula is substituted with an alkaline earth metal ion; Disulfide compounds; Fe2 (MoO4) 3, and the like, but the present invention is not limited thereto.

The conductive material is usually added in an amount of 1 to 30% by weight based on the total weight of the mixture including the cathode active material. Such a conductive material is not particularly limited as long as it has electrical conductivity without causing chemical changes in the battery, for example, graphite such as natural graphite or artificial graphite; Carbon black such as carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, and summer black; Conductive fibers such as carbon fiber and metal fiber; Metal powders such as carbon fluoride, aluminum, and nickel powder; Conductive whiskey such as zinc oxide and potassium titanate; Conductive metal oxides such as titanium oxide; Conductive materials such as polyphenylene derivatives and the like can be used.

The binder is a component which assists in bonding of the active material and the conductive material and bonding to the current collector, and is usually added in an amount of 1 to 30% by weight based on the total weight of the mixture containing the cathode active material. Examples of such binders include polyvinylidene fluoride, polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene , Polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene butylene rubber, fluorine rubber, various copolymers and the like.

The filler is optionally used as a component for suppressing the expansion of the anode, and is not particularly limited as long as it is a fibrous material without causing a chemical change in the battery. Examples of the filler include olefin polymers such as polyethylene and polypropylene; Fibrous materials such as glass fibers and carbon fibers are used.

The negative electrode is manufactured by applying and drying a negative electrode active material on the negative electrode current collector and / or the extended current collector, and may optionally further include the components as described above.

The cathode current collector and / or the extension current collector are generally made to a thickness of 3 to 500 micrometers. The negative electrode current collector and / or the elongated current collector are not particularly limited as long as they have electrical conductivity without causing chemical changes in the battery, and examples thereof include copper, stainless steel, aluminum, nickel, titanium, Surface treated with carbon, nickel, titanium, silver or the like on the surface of copper or stainless steel, aluminum-cadmium alloy, or the like can be used. In addition, like the positive electrode collector, fine unevenness can be formed on the surface to enhance the bonding force of the negative electrode active material, and it can be used in various forms such as films, sheets, foils, nets, porous bodies, foams and nonwoven fabrics.

Examples of the negative electrode active material include carbon such as non-graphitized carbon and graphite carbon; B, P, Si, Group 1 of the periodic table, LixFe2O3 (0? X? 1), LixWO2 (0? X? 1), SnxMe1-xMe'yOz (Me: Mn, Fe, Pb, 2 < / RTI > group III element, halogen, 0 < x < Lithium metal; Lithium alloy; Silicon-based alloys; Tin alloy; Metal oxides such as SnO, SnO2, PbO, PbO2, Pb2O3, Pb3O4, Sb2O3, Sb2O4, Sb2O5, GeO, GeO2, Bi2O3, Bi2O4, and Bi2O5; Conductive polymers such as polyacetylene; Li-Co-Ni-based materials and the like can be used.

The separation membrane is interposed between the anode and the cathode, and an insulating thin film having high ion permeability and mechanical strength is used. The pore diameter of the membrane is generally 0.01 to 10 micrometers, and the thickness is generally 5 to 300 micrometers. Such separation membranes include, for example, olefinic polymers such as polypropylene, which are chemically resistant and hydrophobic; A sheet or nonwoven fabric made of glass fiber, polyethylene or the like is used. When a solid electrolyte such as a polymer is used as an electrolyte, the solid electrolyte may also serve as a separation membrane.

The electrolytic solution may be a non-aqueous electrolytic solution containing a lithium salt, and is composed of a non-aqueous electrolytic solution and a lithium salt. As the non-aqueous electrolyte, non-aqueous organic solvents, organic solid electrolytes, inorganic solid electrolytes, and the like are used, but the present invention is not limited thereto.

Examples of the non-aqueous organic solvent include N-methyl-2-pyrrolidinone, propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, gamma -Butyrolactone, 1,2-dimethoxyethane, tetrahydroxyfuran, 2-methyltetrahydrofuran, dimethylsulfoxide, 1,3-dioxolane, formamide, dimethylformamide, dioxolane , Acetonitrile, nitromethane, methyl formate, methyl acetate, triester phosphate, trimethoxymethane, dioxolane derivatives, sulfolane, methylsulfolane, 1,3-dimethyl-2-imidazolidinone, propylene carbonate Nonionic organic solvents such as tetrahydrofuran derivatives, ethers, methyl pyrophosphate, ethyl propionate and the like can be used.

Examples of the organic solid electrolyte include a polymer electrolyte such as a polyethylene derivative, a polyethylene oxide derivative, a polypropylene oxide derivative, a phosphate ester polymer, an agitation lysine, a polyester sulfide, a polyvinyl alcohol, a polyvinylidene fluoride, Polymers containing ionic dissociation groups, and the like can be used.

Examples of the inorganic solid electrolyte include nitrides of Li such as Li3N, LiI, Li5NI2, Li3NLiI-LiOH, LiSiO4, LiSiO4-LiI-LiOH, Li2SiS3, Li4SiO4, Li4SiO4- LiI- LiOH, Li3PO4- Li2S- Halides, sulfates and the like can be used.

The lithium salt is a substance that is soluble in the non-aqueous electrolyte. For example, LiCl, LiBr, LiI, LiClO4, LiBF4, LiB10Cl10, LiPF6, LiCF3SO3, LiCF3CO2, LiAsF6, LiSbF6, LiAlCl4, CH3SO3Li, CF3SO3Li, 2NLi, chloroborane lithium, lower aliphatic carboxylic acid lithium, lithium 4-phenylborate, imide and the like can be used.

For the purpose of improving the charge-discharge characteristics and the flame retardancy, the nonaqueous electrolytic solution is preferably a solution prepared by dissolving or dispersing in a solvent such as pyridine, triethylphosphite, triethanolamine, cyclic ether, ethylenediamine, glyme, hexaphosphoric triamide, N, N-substituted imidazolidine, ethylene glycol dialkyl ether, ammonium salt, pyrrole, 2-methoxyethanol, aluminum trichloride and the like may be added have. In some cases, halogen-containing solvents such as carbon tetrachloride and ethylene trifluoride may be further added to impart nonflammability. In order to improve the high-temperature storage characteristics, carbon dioxide gas may be further added. FEC (Fluoro-Ethylene Carbonate, PRS (Propene sultone), and the like.

In one specific example, a lithium salt such as LiPF6, LiClO4, LiBF4, LiN (SO2CF3) 2 or the like is dissolved in a mixed solvent of a cyclic carbonate of EC or PC which is a high-dielectric solvent and a linear carbonate of DEC, DMC or EMC To thereby prepare a lithium salt-containing non-aqueous electrolyte.

As described above, the battery pack according to the present invention has a structure in which the battery pack is mounted on one first housing per battery cell, and the battery cells thus mounted are packaged in a second housing. It is possible to prevent the external impact from being applied directly to the battery cells, thereby preventing deformation and breakage of each of the battery cells, thereby further improving safety.

1 is a schematic view of a battery pack according to the prior art;
2 is a schematic view of a battery pack according to an embodiment of the present invention;
3 is a partial side view of a battery pack according to one embodiment of the present invention;
4 is a partial vertical sectional view of a battery pack according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings, but the present invention is not limited by the scope of the present invention.

2 is a schematic diagram of a battery pack 100 according to an embodiment of the present invention.

Referring to FIG. 2, the battery pack 100 has a cylindrical shape and includes a plurality of battery cells 101 having electrode terminals formed at the upper and lower ends of the cylinder, a battery cell 100 (not shown) The first and second housings 110 and 110 are formed to have an inner hollow structure so as to surround the remaining outer surfaces of the first and second housings 110 and 101. The first and second housings 110 and 110, A second housing 120 configured to accommodate both the battery cells 101 mounted on the first housings 110 and the bus bar assembly 130 and a bus bar assembly 130 electrically connected to the bus bar assembly 130, And a protection circuit (140) for controlling the charge / discharge voltage or current of the battery pack (100).

The battery pack 100 also has a structure in which a connection portion 102 is formed between the first housings 110 and the first housings 110 are connected to each other with the connection portion 102 interposed therebetween.

The bus bar assembly 130 connects the battery cells 101 mounted on the first housing 110 to each other so that the plurality of connecting members 131 and the connecting members 131 are inserted and mounted. And a bar plate 132, which are mounted at positions facing electrode terminal portions of the battery cells 101.

Accordingly, the battery cells 101 mounted in the second housing 120 are arranged in such a manner that all the outer surfaces of the battery cells 101 are wrapped by the first housing 110 and the bus bar assembly 130, The outer surface of the first housing 110 except for the electrode terminal is surrounded by the first housing 110 and the electrode terminal portion is in close contact with the bus bar assembly 130. As a result, a substantial impact applied to the battery cell 101 as a shock from the outside is buffered and relaxed in the second housing 120, the first housing 110, and the bus bar assembly 130 can be greatly reduced.

The connection unit 102 will be described in more detail with reference to FIG.

3 is a partial side view of a battery pack according to an embodiment of the present invention.

Referring to FIG. 3, FIG. 3- (a) is a side view in which one connection portion 102 is formed, FIG. 3 (b) is a side view in which two connection portions 102 are formed, but the shape and number are not limited thereto .

The connection unit 102 is connected to the first housings 110, which are adjacent to each other, in such a manner that they are separated from each other by a predetermined distance so as to allow air to flow therethrough.

That is, the connecting portion 102 forms a ventilation hole 103 through which the air flows by separating the first housings adjacent to each other by a predetermined distance, so that the heat generated in the battery cell 101 is transmitted to the ventilation hole 103). ≪ / RTI >

In addition, when an external impact occurs, the impact force is dispersed into the empty space of the ventilation hole 103, so that the force directly applied to the battery cell 101 can be reduced.

In one embodiment of the present invention, the first housing 110 has a structure in which two units 111 and 112 are engaged with each other. That is, the battery pack 100 according to the present invention is spaced apart from the first housings 110 by a predetermined distance in a state where the first housings 110 are connected to the connecting portion 102, So that the cooling efficiency of the battery cells 101 is high.

Here, the two-unit members 111 and 112 each have a hollow structure having an inner surface shape corresponding to the outer shape of the battery cell except for the electrode terminal portion, and at least one of the two unit members has a connection portion 102 Is formed.

On the outer surface of the first housing 110, a plurality of beads 114 are formed in a direction corresponding to the longitudinal direction thereof.

The beads 114 may form an air flow inducing path for inducing a flow of air flowing along the outer surface of the first housing 110 between the electrode terminals formed at both ends of the battery cell 101, The air flowing from the outside through the battery cells 101 flows through the battery cells 101 to discharge the heat generated in the battery cells 101 to the outside.

The second housing 120 includes the battery cells 101 mounted on the first housing 110, the protection circuit 140 and the mounting portion 121 (not shown) having one side opened to house the bus bar assembly 130 therein And a cover 122 mounted on an opening face of the mounting portion 121 so as to seal the open side face of the mounting portion 121. [

The mounting portion 121 and the cover 122 will be described in more detail with reference to FIG.

4 is a partial vertical sectional view of a battery pack according to an embodiment of the present invention.

Referring to FIG. 4, a slot 154 for mounting a protection circuit 140 is formed in the mounting portion 121 so that the protection circuit 140 is slidably mounted.

The slot 154 has a structural advantage in that it facilitates mounting and replacement of the protection circuit 140. In the present invention, a space 154 is formed between the protection circuit 140 and the second housing 120 on the slot 154. [ And it is possible to prevent the external impact from being directly applied to the protection circuit 140 through the second housing 120.

In this structure, in the battery pack 100 of the present invention, the partition 152 partitioning the slot 154 and the battery cell 101 mounted on the first housing 110 is mounted on the mounting portion 121 Lt; / RTI > structure.

The partition 152 is made of a concavo-convex structure including concave portions and convex portions in a vertical section in order to absorb the impact more flexibly with respect to external force.

The padding of such a structure may be made of a metal material having mechanical rigidity or an elastic polymer material, and may be made of the same material as that of the first housing.

The shape of the partition is not a simple plate type but has an arrangement of complementary concave portions and convex portions so as to absorb shock and vibration applied to the battery cells 101 and the protection circuit 140 while being elastically warped with respect to external force can do.

It should also be noted that it is possible to induce a vortex while inducing the flow of air through the concave and convex portions, thereby making it possible to increase the uniformity of the refrigerant and the cooling efficiency with the refrigerant at a higher flow rate.

In addition, the second housing has slits 126a formed with a plurality of slits, which are formed in the second housing to increase the cooling efficiency by forming the air flow paths.

For example, although the first slit portion 126b and the second slit portion 126c formed in two shapes are illustrated in FIG. 4, the present invention is not limited thereto. The slit portion 126b may have a plurality of slit portions, The shape of the inner slit may be variously formed.

However, for ease of explanation, a process of allowing air to flow through the first slit portion 126b and the second slit portion 126c of FIG. 4 to cool the internal battery pack will be described.

4, the second housing has a first slit part 126b formed at one side of the mounting part 121 and having a plurality of slits for inflow of air into the mounting part and air discharge to the outside, A second slit portion 126c having a plurality of slits formed therein for introducing air into the cover and discharging air to the outside, and a handle 124 for gripping the battery pack.

Accordingly, when air is introduced from the first slit part 126b, the second housing may have a first air discharge path through which air is discharged to the second slit part 126c, or a second air discharge path may be formed through the second slit part 126c A second air discharge path through which air is discharged to the first slit portion 126b may be formed.

More specifically, the air introduced from one slit part passes between the battery cells 101 separated by the connecting part 102, absorbs heat generated in the battery cells 101, .

In the above description, the air flow is described through the two configurations of the first slit portion 126b and the second slit portion 126c. However, the air flow is not limited to this, and the air flow may proceed through the plurality of slit portions, An air flow is generated and the battery cells 101 can be cooled.

In addition, the handle 124 is formed in a hollow structure, and at least one hole is perforated so that the air introduced from the first slit portion or the second slit portion is discharged to the outside through the handle, The discharge path can be formed.

In addition, since the third air discharge path can be further formed in the first air discharge path or the second air discharge path, the cooling efficiency for cooling the battery cells 101 can be increased.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

100: Battery pack
101: a plurality of battery cells
102:
103: Vents
110: first housing
111, and 112: 2 units
114: a plurality of beads
120: second housing
121:
122: cover
124: Handle
126a:
126b: first slit part
126c: a second slit part
130: bus bar assembly
131: a plurality of connecting members
132: bus bar plate
140: Protection circuit
152: partition
154: Slot

Claims (16)

A battery pack formed by a dual structure,
A plurality of battery cells each having a cylindrical shape and each having an electrode terminal formed at an upper end and a lower end of the cylinder;
The first and second housings being formed in an inner hollow structure so as to enclose the remaining outer surfaces of the battery cells except the upper and lower ends where the electrode terminals are formed;
A bus bar assembly electrically connecting the battery cells mounted on the first housings;
A second housing configured to accommodate both the battery cells and the bus bar assembly mounted on the first housings; And
A protection circuit part for controlling charge / discharge voltage or current of the battery pack;
And the battery pack (10).
The method according to claim 1,
A connecting portion is formed between adjacent first housings;
Wherein the first housings are connected to each other with a connecting portion therebetween. 3. The battery pack according to claim 2, wherein the connection part forms a vent hole through which the air flows by spacing the first housings adjacent to each other by a predetermined distance.
The battery pack according to claim 3, wherein the predetermined distance is 10% to 30% of the diameter of the battery cell.
The battery pack according to claim 2, wherein a plurality of beads are formed on the outer surface of the first housing in a direction corresponding to the longitudinal direction thereof.
6. The battery pack according to claim 5, wherein the beads form an air flow guide path for guiding a flow of air flowing along an outer surface of the first housing between electrode terminals formed at both ends of the battery cell.
The battery pack according to claim 5, wherein the beads are arranged along an outer diameter of the first housing in a state of being spaced apart by a predetermined distance.
The battery pack according to claim 7, wherein the beads are heat dissipation fins that heat exchange with gas refrigerant flowing between the beads in a state that the heat of the battery cells mounted on the first housing is conducted.
The battery pack according to claim 7, wherein the predetermined distance is 100% to 500% of the width of the bead.
3. The method of claim 2,
Two units of members are mutually engaged to form a first housing;
Wherein the two unit members are each a hollow structure having an inner surface shape corresponding to an outer shape of the battery cell except for the electrode terminal portion;
And a connection part is formed on at least one of the two unit members.
The apparatus of claim 1, wherein the second housing comprises:
A mounting portion having one side opened to receive the battery cells, the protection circuit portion, and the bus bar assembly mounted in the first housing; And
A cover mounted on an open side of the mounting portion to seal an open side of the mounting portion;
The battery pack comprising:
[12] The apparatus of claim 11, wherein the mounting portion is formed with a slot for mounting a protection circuit,
Wherein a partition for partitioning a portion where the battery cells mounted on the first housing and the slot are mounted is mounted on the mounting portion.
13. The battery pack as claimed in claim 12, wherein the partition has a concave-convex structure including a concave portion and a convex portion in a vertical cross section.
12. The apparatus of claim 11, wherein the second housing comprises:
A first slit part formed at one side of the mounting part and having a plurality of slits for inflow of air into the mounting part and air discharge to the outside;
A second slit portion formed at one side of the cover with a plurality of slits for air inflow into the cover and air exhaust to the outside; And
A handle for gripping the battery pack; Further comprising:
When air is introduced from the first slit portion, a first air discharge path through which air is discharged to the second slit portion is formed
And a second air discharge path through which air is discharged to the first slit portion when air flows in the second slit portion.
15. The handle of claim 14,
Wherein at least one of the first and second slit portions is formed with a hollow structure and at least one hole is perforated to form a third air discharge path through which the air introduced from the first slit portion or the second slit portion is discharged to the outside through the handle Battery pack.
A device using the battery pack according to any one of claims 1 to 15 as a power source.

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