Title of invention: Battery pack with improved safety
technical field
[One]
This application claims the benefit of priority based on Korean Patent Application No. 2020-0001345 dated January 6, 2020, and all contents disclosed in the literature of the Korean patent application are incorporated as a part of this specification.
[2]
The present invention relates to a battery pack with improved safety and a secondary battery including the same, and more particularly, to an electrode assembly, two or more sub-modules in which a plurality of unit cells including an electrode lead protruding from the electrode assembly are disposed; A pack case for accommodating the sub-module, a bus bar assembly including a bus bar for electrically connecting electrode leads of the sub-module, and a bus bar frame connected thereto, a connection bus bar for connecting between the sub-modules; Electrode leads electrically connected by the bus bar are gathered and formed, and a terminal part for connection to the connection bus bar, and the upper end and side of the connection bus bar of the terminal part, the bus bar assembly, and a part connected to the terminal part are formed. To a battery pack including a blocking structure surrounding the same, and to a secondary battery.
background
[3]
As technology development and demand for mobile devices such as cell phones, laptops, camcorders, and digital cameras increase, technologies related to rechargeable batteries that can be charged and discharged are becoming active. In addition, secondary batteries are an alternative energy source for fossil fuels that cause air pollutants, and are applied to electric vehicles (EV), hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (P-HEV), etc. The need for the development of secondary batteries is increasing day by day.
[4]
Due to the increasing demand for secondary batteries and the need for high-capacity batteries, various attempts have been made to increase the capacity of the secondary battery itself. In some cases, the capacity of one battery cell itself is increased and used, but in general, a plurality of battery cells are electrically connected and used as one battery. It is generally preferred to form a battery module in which a plurality of battery cells are electrically connected to each other in series or parallel form, and to accommodate the plurality of battery modules in a battery case and use the battery module in the form of a battery pack.
[5]
However, in the case of a high-capacity battery or battery pack, it is difficult to cool the heat in the battery compared to a single battery cell, so there is a greater risk of thermal runaway, fire, or explosion. To this end, to improve the safety of the entire battery pack, a separate alarm system is provided or a configuration capable of cooling and extinguishing is added.
[6]
As described above, the safety of the battery pack is secured by adding a separate member to the battery pack or changing the structure of the battery pack. No consideration is given to prevent the transfer of thermal runaway by preventing fire, etc. from propagating to adjacent modules.
[7]
1 shows a perspective view of a battery pack according to the prior art. In a conventional battery pack, two or more sub-modules 10 in which a plurality of unit cells are disposed, a terminal unit 20 formed by collecting electrode leads of the sub-module 10, and the terminal unit 20 are connected, and the A connection bus bar 30 for connecting the sub-modules 10 is included, and the terminal unit 20 and the connection bus bar 30 are covered with a bolt cover 40 for insulation.
[8]
This bolt cover 40 is a configuration that exists for insulation, and covers only a part of the terminal part 20 and the connection bus bar 30 connected thereto in a plate shape, or a cap that fits the terminal part 20 as shown in FIG. 1 . It exists in the form that covers the form.
[9]
However, the bolt cover 40 as described above does not protect the bus bar assembly 50 coupled with the electrode leads of the terminal part 20 and the sub-module 10 . In particular, when a fire occurs in an adjacent module like the battery pack according to the prior art as shown in FIG. 1 , through the connection part between the terminal part 20 and the connection bus bar 30 , which are relatively exposed compared to other parts, Heat is transferred and it is easy to cause a chain fire. In addition, conductive contaminants from the damaged module penetrate into the connection part of the terminal part 20 and the connection bus bar 30 to damage the sub-module 10 or cause a disconnection to cause a fire. do.
[10]
In Patent Document 1, a terminal cover is provided to protect the electrode terminal, but this is for connection with an external device. In addition, the terminal cover of Patent Document 1 is in the form of a cap that can cover only the terminal, and only has an O-ring for easy attachment and detachment, and does not have a separate structure for protecting from fire or pollutants.
[11]
In Patent Document 2, there is a terminal cover for protecting the electrode terminal, but this is a flexible material that can be elastically deformed, and is not a structure for protecting the terminal from fire or pollutants. In addition, the terminal cover is configured to protect the terminal outside the battery pack, and is not configured to protect the battery module and the connection part between the modules.
[12]
A configuration is required to prevent thermal runaway transfer of sub-modules in the battery pack and protect the battery module from the outside.
[13]
-Prior art literature-
[14]
-Patent Literature-
[15]
(Patent Document 1) Republic of Korea Patent Publication No. 2018-0058552
[16]
(Patent Document 2) Republic of Korea Patent Publication No. 2019-0088675
DETAILED DESCRIPTION OF THE INVENTION
technical challenge
[17]
In order to solve the above problems, in the present invention, the terminal portion of the sub-module and the connecting bus bar for electrically connecting the sub-modules and a blocking structure for protecting the bus bar assembly are provided to expose the exposed portion of each sub-module. It is intended to protect submodules by wrapping
[18]
In addition, the purpose of the blocking structure is to not affect an adjacent sub-module even if an abnormality occurs in a specific sub-module by configuring the blocking structure with heat-resistant and chemical-resistant materials.
[19]
Furthermore, it aims to prevent property and non-property damage by preventing a chain fire or explosion by protecting each sub-module.
means of solving the problem
[20]
A battery pack according to the present invention for solving the above problems includes: an electrode assembly, two or more sub-modules in which a plurality of unit cells including an electrode lead protruding from the electrode assembly are disposed; a pack case for accommodating the sub-module; A bus bar assembly including a bus bar for electrically connecting the electrode leads of the sub-modules and a bus bar frame connected thereto, a connecting bus bar for connecting between the sub-modules, and electrode leads electrically connected by the bus bars It may include a terminal part formed together and connected to the connection bus bar, and a blocking structure surrounding the top and side surfaces of the connection bus bar of the terminal part, the bus bar assembly, and a part connected to the terminal part.
[21]
The blocking structure may be made of an insulating material having chemical resistance and thermal insulation properties.
[22]
The insulating material may include silicate.
[23]
The insulating material may include mica or ceramic.
[24]
The blocking structure is configured in a shape corresponding to the bus bar assembly, and a terminal protruding in a shape corresponding to the upper structure located at the upper end of the bus bar assembly, the terminal part from the upper structure, and the connecting bus bar. a protective part, a side structure that further protects the other sub-module facing part of the bus bar frame, and a pollutant penetration prevention part that is located below the upper structure and protects both sides of the terminal part and the connecting bus bar can
[25]
The pollutant penetration preventing unit may be coupled to a space between the bus bar, the terminal unit, and the connection bus bar connected thereto.
[26]
The blocking structure may further include an insulating cover for protecting the blocking structure.
[27]
The heat insulating cover may include a top cover that exists above the battery pack on which the bus bar assembly and the blocking structure are present, and a side cover that exists on a part facing other sub-modules of the bus bar assembly.
[28]
The heat insulating cover may be made of a heat insulating material.
[29]
The insulating material may include silicate.
[30]
The insulating material may include mica or ceramic.
[31]
The heat insulating cover may completely cover the connection bus bar.
[32]
The heat insulating cover may further include a rear cover that exists in parallel with the side cover and protects a rear surface of the connection bus bar and the blocking structure.
[33]
The present invention also includes a device using a battery pack corresponding to any one of the above as an energy source.
[34]
The device may be any one selected from the group consisting of a mobile phone, a tablet computer, a notebook computer, a power tool, a wearable electronic device, an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, and a power storage device.
[35]
In the present invention, one or two or more non-conflicting configurations among the above configurations may be selected and combined.
Brief description of the drawing
[36]
1 is a perspective view of a battery pack according to the prior art.
[37]
2 is a perspective view of a battery pack according to a first preferred embodiment of the present invention.
[38]
3 is a perspective view of the blocking structure according to the first preferred embodiment of the present invention as viewed from the rear.
[39]
4 is a front view of a blocking structure according to a first preferred embodiment of the present invention.
[40]
5 is a side view of a blocking structure according to a first preferred embodiment of the present invention;
[41]
6 is a perspective view of a battery pack according to a second preferred embodiment of the present invention.
[42]
7 is a perspective view of an insulating cover present in a battery pack according to a third preferred embodiment of the present invention.
[43]
8 is a perspective view of a battery pack according to a third preferred embodiment of the present invention before assembly.
[44]
9 is a perspective view after the battery pack is assembled according to a third preferred embodiment of the present invention.
[45]
10 is a modified example of the third preferred embodiment of the present invention.
[46]
11 is a graph of resistance measurement of a battery pack according to a second preferred embodiment of the present invention and a comparative example.
[47]
12 is a schematic diagram illustrating the arrangement of a battery pack according to a second preferred embodiment of the present invention and sub-modules for resistance measurement of a comparative example.
Modes for carrying out the invention
[48]
In the present application, terms such as "comprises", "have" or "include" are intended to designate that the features, numbers, steps, components, parts, or combinations thereof described in the specification exist, and are intended to indicate that one or more other It should be understood that this does not preclude the possibility of addition or presence of features or numbers, steps, operations, components, parts, or combinations thereof.
[49]
In addition, the same reference numerals are used throughout the drawings for parts having similar functions and functions. Throughout the specification, when it is said that a part is connected to another part, it includes not only a case in which it is directly connected, but also a case in which it is indirectly connected with another element interposed therebetween. In addition, the inclusion of a certain component does not exclude other components unless otherwise stated, but means that other components may be further included.
[50]
Hereinafter, a battery pack including a blocking structure according to the present invention and a secondary battery including the same will be described with reference to the accompanying drawings.
[51]
2 is a perspective view of a battery pack according to a first preferred embodiment of the present invention, FIG. 3 is a perspective view of a blocking structure according to a first preferred embodiment of the present invention as viewed from the rear side, and FIG. 4 is a first preferred embodiment of the present invention. It is a front view of the blocking structure according to the embodiment, and FIG. 5 is a side view of the blocking structure according to the first preferred embodiment of the present invention.
[52]
Referring to FIG. 2 , the battery pack according to the first embodiment of the present invention has two or more sub-modules 100 in which a plurality of unit cells including an electrode assembly and an electrode lead protruding from the electrode assembly are disposed. , a bus bar assembly 500 including a pack case 600 for accommodating the sub-module, a bus bar 510 for electrically connecting electrode leads of the sub-module, and a bus bar frame 520 connected thereto , a connecting bus bar 300 for connecting between the sub-modules, a terminal part connected to the connecting bus bar, electrode leads electrically connected by the bus bar, and a bus for fixing the bus bar frame and a bar frame cover, and a blocking structure 400 surrounding the terminal unit, the bus bar assembly 500, and the top and side surfaces of the connection bus bar connected to the terminal unit.
[53]
In the sub-module 100, a plurality of unit cells including an electrode assembly and an electrode lead protruding from the electrode assembly are disposed.
[54]
The electrode assembly is a jelly-roll type electrode assembly having a structure that is wound after a separator is interposed between a long sheet-shaped positive electrode and a negative electrode, or unit cells of a structure in which a rectangular positive electrode and a negative electrode are stacked with a separator interposed therebetween A stack-type electrode assembly composed of a stack-folding-type electrode assembly in which unit cells are wound by a long separation film, or a lamination-stack-type electrode assembly in which unit cells are stacked and attached to each other with a separator interposed therebetween, etc. may be made, but is not limited thereto.
[55]
The electrode assembly as described above is built into the pack case 600 , and the pack case 600 may generally have the same material as the inner layer and the outer layer, but different materials may be used for each part. The inner layer in direct contact with the electrode assembly has insulation and electrolyte resistance, and for sealing with the outside, the sealing property, that is, the sealing portion where the inner layers are thermally bonded to each other, must have excellent thermal bonding strength. The material of the inner layer may be selected from polyolefin resins such as polypropylene, polyethylene, polyethylene acrylic acid, polybutylene, etc., polyurethane resins and polyimide resins having excellent chemical resistance and good sealing properties, but is not limited thereto, Specifically, polypropylene excellent in mechanical properties and chemical resistance such as tensile strength, rigidity, surface hardness, and impact strength may be used.
[56]
For the outer layer, a heat-resistant polymer having excellent tensile strength, moisture permeability and air permeability prevention properties may be used to secure heat resistance and chemical resistance while protecting the electrode assembly. For example, nylon or polyethylene terephthalate may be used, but these is not limited to
[57]
On the other hand, the electrode leads composed of a positive electrode lead and a negative electrode lead may have a structure in which the positive tab and the negative tab of the electrode assembly are electrically connected, respectively, and then are exposed to the outside of the pack case, and the lead is directly connected to the electrode assembly without the positive electrode tab and the negative electrode tab It may be a structure connecting the outside and the pack case, but is not limited thereto. At this time, the part where the electrode leads are gathered and exposed to the outside of the pack case is called a terminal part (not shown in FIG. 2, see FIG. 1), and such a terminal part (not shown in FIG. 2, see FIG. 1) is electrically connected to the sub-modules. It is connected to the connection bus bar 300 for connection. Since the battery cells as described above correspond to generally known configurations, a detailed description thereof will be omitted.
[58]
The sub-module 100 means that a plurality of unit cells including an electrode assembly and an electrode lead extending from the electrode assembly are stacked side by side in a horizontal or vertical direction to match the capacity or output of the battery pack.
[59]
A plurality of sub-modules 100 as described above are again arranged side by side and then accommodated in the pack case 600 .
[60]
The bus bar assembly 500 is for fixing the unit cells constituting the sub-module 100 to the pack case 600 while connecting them in series or in parallel, and includes one or more bus bar frames 520 and one or more buses. A bar 510 and a connecting bus bar 300 are included.
[61]
The positive lead or the negative lead extended from the electrode assembly of each unit cell is bent through the bus bar 510 and then fixed to the outer surface of the bus bar 510 through a known fixing method such as laser welding or resistance welding. do.
[62]
In addition, in order to connect the sub-modules 100 in series, a connection bus bar 300 bent in a predetermined shape is provided between the sub-modules 100 positioned adjacently, and, like the bus bar 510 , a known fixed The bus bars 510 are connected to each other through means.
[63]
As can be seen in FIG. 2 , the battery pack according to the present invention includes a blocking structure 400 surrounding the top and side surfaces of the terminal unit, the bus bar assembly 500 and the connecting bus bar 300 .
[64]
The blocking structure 400 is configured in a shape corresponding to the bus bar assembly as shown in FIGS. 2 to 5 , and includes an upper structure 410 positioned at an upper end of the bus bar assembly, the terminal part and the terminal part in the upper structure. The terminal protection unit 420 protruding in a shape corresponding to the connection bus bar, the side structure 430 that further protects the other sub-module facing portions of the bus bar frame 520, and the upper structure 410 are located below the , it may include a contaminant penetration prevention unit 440 protecting both sides of the terminal unit and the connection bus bar 300 .
[65]
The upper structure 410 is positioned on the upper end of the bus bar assembly 500 to protect the bus bar 510 and the bus bar frame 520 . To this end, the upper structure 410 is configured in a form in which the upper portion is formed in a plate shape to be easily combined with other components of the battery pack, such as an insulating cover or a cooling plate.
[66]
In addition, the lower portion of the upper structure 410 has a shape corresponding to the top of the bus bar 510 and the bus bar frame 520 . In addition, a separate fixing part for fixing the upper structure 410 may be present in the bus bar 510 and the bus bar frame 520 .
[67]
Since the upper structure 410 has the above-described shape, upper portions of the bus bar 510 and the bus bar frame 520 may not be exposed to the outside.
[68]
The blocking structure 400 may include a terminal protection unit 420 protruding in a shape corresponding to the terminal unit and the connection bus bar 300 . The terminal protection part 420 has a shape surrounding the terminal part and the upper end and the side surface of the connection bus bar 300 connected to the terminal part. The terminal protection part 420 protrudes in a shape corresponding to the terminal part and the connection bus bar 300 to minimize the protrusion part. This is to increase the overall capacity of the battery pack by reducing the size of the battery module.
[69]
The terminal protection part 420 is formed to surround the part connected to the terminal part and the part of the connection bus bar 300 present in the connection bus bar receiving part 12 of the cartridge 11 shown in FIG. 1 .
[70]
The side structure 430 protects the other sub-module facing portion of the bus bar frame 520 . The bus bar frame facing portion of the side structure 430 is formed in a shape corresponding to the shape of the bus bar frame 520 and the bus bar 510 . The other sub-module facing portion of the side structure 430 is preferably in the form of a plate so that other members do not engage or interfere with other members. Such a shape may vary depending on the shape of the battery pack and the battery module.
[71]
The side structure 430 may be configured to protect all or part of the bus bar 510 and the bus bar frame 520 , but may protect a portion where the bus bar 510 and the electrode lead are connected. It is preferable to have a length that can be In addition, when the bus bar and the bus bar frame are made of a plastic material that is weak to heat or chemicals, it is preferable to protect both the plastic material part of the bus bar and the bus bar frame.
[72]
The contaminant penetration prevention unit 440 protects both sides of the terminal unit and the connection bus bar 300 . The contaminant penetration prevention unit 440 protects an empty space formed in the bus bar 20 present on both sides of a coupling point between the terminal unit and the connection bus bar 30 shown in FIG. 1 .
[73]
The pollutant penetration prevention unit 440 may be coupled to a space between the bus bar, the terminal unit, and the connection bus bar connected thereto. To this end, the contaminant penetration prevention unit 440 according to the present invention may have a shape extending downward from the upper structure 410 as shown in FIG. 3 . In addition, the contaminant penetration prevention unit 440 may have a protrusion protruding toward the non-face-to-face portion of the terminal unit to fix the blocking structure 400 while preventing the contaminant penetration.
[74]
The pollutant penetration prevention part 440 may have a right-angled triangular shape in which an upper portion of the protrusion is disposed parallel to the upper structure as shown in FIG. 4 . The upper portion of the protrusion is disposed parallel to the upper structure, so that when the contaminant seeps into the interior, it moves to a portion other than the exposed portion.
[75]
The protrusion may be 0.1 times to 0.7 times the length of the contaminant penetration prevention part 440 as shown in FIG. 5 . If the length of the protrusion is too short, the contaminant penetration prevention part 440 may not be fixed and may be damaged even in a small flow. In addition, when the length of the protrusion is excessively long, the size of the pollutant penetration prevention unit 440 may become excessively large, thereby limiting the battery shape and battery size for output or capacity of the battery.
[76]
The contaminant penetration prevention part 440 may exist in a form that is not connected to the side structure 430 as shown in FIG. 5 . The blocking structure 400 is fixed to the bus bar assembly 500 by allowing the protrusion of the bus bar 510 to enter the space between the side structure 430 and the contaminant penetration prevention part 440 . because you can make it happen.
[77]
As shown in FIGS. 3 to 5 , the blocking structure 400 according to the present invention may have a fixing part 450 on each side of the lower portion of the upper structure 410 . The fixing part 450 serves to fix the blocking structure 400 to the bus bar assembly 500 or to support the blocking structure 400 .
[78]
The fixing part 450 may have a longer shape as shown in FIG. 5 , and a shorter shape as it approaches the connection bus bar 300 of the module to which it is connected. This is a structure for arranging the blocking structure 400 so that flames generated from other modules do not move.
[79]
As shown in FIG. 4 , the fixing part 450 has a shorter shape than the pollutant penetration preventing part 440 . This is because, unlike the contaminant penetration prevention part 440 , the fixing part 450 is not coupled to the recessed part of the bus bar assembly 500 and thus does not need to be deep. In addition, when the fixing part 450 is too long, the space occupied by the blocking structure 400 in the battery pack becomes too large, which is inefficient and may reduce the flame prevention effect.
[80]
The blocking structure 400 according to the present invention may include a connection bus bar accommodating part 460 for accommodating the connection bus bar 300 as shown in FIGS. 3 to 4 . The upper structure 410 surrounds the space for accommodating the connection bus bar accommodating part 460 , that is, the connection bus bar. The connecting bus bar accommodating part 460 is formed to have the same size as the connecting bus bar 300 , so that when the connecting bus bar 300 is coupled, foreign substances cannot penetrate.
[81]
The blocking structure 400 may be made of an insulating material having chemical resistance and thermal insulation properties to prevent the sub-module 100 from being damaged by fire or contamination of an adjacent sub-module. As the insulating material having chemical resistance and thermal insulation properties, any material that can be used in a battery may be used, but considering the use of a battery pack, a material that is light and does not generate toxic substances is preferable.
[82]
An example of such a material is a compound containing silicon. Examples of the silicon-containing compound include mica and ceramics. In addition, it can be used as a material of the barrier structure 400 by coating a heat-resistant polymer such as nylon or polyethylene terephthalate to prevent it from reacting with chemicals.
[83]
The blocking structure 400 may use a single material, but may use a different material according to each facing portion. As an example, a material with superior chemical resistance may be used for the sub-module facing part, and a material with superior heat resistance may be used for the sub-module facing part and the upper part of the sub-module.
[84]
In addition, the blocking structure 400 may be composed of one plate, but may be composed of two or more layers. However, it is preferable that the blocking structure 400 is a single plate so that the thickness is not excessively thick. When the blocking structure 400 is two or more plates, like a firewall, it may be configured in a form in which a honeycomb-shaped core is formed between the plates. Insulation may also be present between the plates. Examples of such insulating materials include mineral board, CFB, ceramic fiber hard board, and Super HTB.
[85]
The thickness of the blocking structure is preferably a thickness to protect the sub-module 100 from flames and contaminants. The thickness may vary depending on the thickness and capacity of the sub-module and battery pack, but is preferably 0.2 mm or more and 50 mm or less. If it is 0.2 mm or less, the sub-module 100 cannot be protected from chemicals and flames, and if it is 50 mm or more, the size of the sub-module 100 is increased to reduce the density and capacity of the battery pack.
[86]
6 is a perspective view of a battery pack according to a second preferred embodiment of the present invention.
[87]
The battery pack according to the second embodiment of the present invention may further include side protection units 700 on both side portions of the upper structure 410 of the blocking structure 400 of the battery pack according to the first embodiment.
[88]
The side protection unit 700 may be configured to protect not only the upper structure 410 but also the side surface of the contaminant penetration prevention unit 440 as shown in FIG. 6 . In addition, the side protection part 700 may be present at the upper end of the upper structure 410 as shown in FIG. 6 , or may exist under the upper structure. In addition, although it may exist as a separate member as shown in FIG. 6 , it may exist integrally with the blocking structure 400 .
[89]
The battery pack according to the present invention may further include a heat insulating cover 800 .
[90]
7 is a perspective view of a heat insulating cover 800 present in a battery pack according to a third preferred embodiment of the present invention. The heat insulating cover 800 is present to protect the blocking structure 400 . Of course, a structure for protecting a general terminal cover without the blocking structure 400 is also possible.
[91]
The heat insulating cover 800 is a top cover 810 that exists above the battery pack in which the bus bar assembly 500 and the blocking structure 400 are present, and the other sub-module facing portion of the bus bar assembly 500 . It may include a side cover 820 present in the. The heat insulating cover 800 may further include a fastening device 830 for coupling the heat insulating cover 800 to the bus bar assembly and the sub-module 100 . The fastening device 830 may be fixed to the heat insulating cover 800 by being fitted in a clip shape, or may be formed as a part of the heat insulating cover 800 .
[92]
The upper part of the top cover 810 is configured in a flat plate shape, and the lower part is configured in a shape corresponding to the coupling portion, but it is generally preferable to have a plate shape. The size of the top cover 810 is preferably a size that can cover the blocking structure. That is, the upper end of the bus bar assembly 500 may be included from the outermost side of the other module facing portion of the sub-module 100 according to the present invention, and the size may be in contact with the surface of the connection bus bar 300 . In addition, the heat insulation cover 800 according to the present invention may cover all of the connection bus bars 300 existing at the top of the sub-module 100 as shown in FIG. 10 , or may cover only a part of the connection bus bars 300 . . This helps prevent fire or heat caused by a fire back that spreads the fire to the ignition point.
[93]
The side cover 820 has the same upper portion as the upper portion of the upper cover 810 in the form of a flat plate, and the lower portion is formed in a form corresponding to the coupling portion. The size of the side cover 820 may be the same as or larger than that of the side structure 430 of the blocking structure 400 . The blocking structure 400 may be sized to protect the electrode terminals of the bus bar assembly 500 and the sub-module 100 .
[94]
The fastening device 830 is located on both sides of the heat insulating cover 800 to fix the heat insulating cover 800 to the bus bar assembly and the sub-module 100. Any position is irrelevant as long as the insulating cover 800 is positioned so as not to be separated by impact, fire, explosion, or the like.
[95]
The shape of the fastening device 830 is not limited as long as it can increase the fastening force. Both the cover 810 and the side cover 820 may be fixed to the bus bar assembly and the sub-module 100, or the side cover 820 may be fixed in addition thereto. In addition, only a certain locking part exists in the top cover, and when fixed to the side cover, there may be a fixing part in a form that cannot be detached. This is according to the gravity applied to the top cover 810 , and may vary depending on the position of the sub-module and the position of the heat insulating cover 800 .
[96]
8 is a perspective view before the battery pack according to a third preferred embodiment of the present invention is assembled, and FIG. 9 is a perspective view after the battery pack is assembled according to a third preferred embodiment of the present invention.
[97]
As can be seen in FIGS. 8 to 9 , the fastening device 830 according to the present invention may be coupled to the coupling part 530 present at the upper end of the bus bar assembly 500 . As an example of the fastening device, as shown in FIG. 9 , a side fastening device 831 for fixing the side cover 820 and an upper fastening device 832 for fixing the top cover 810 are one fastening device fixing part. 833, the side fastening device 831 and the upper fastening device 832 are coupled to the upper end or coupling portions 530 present at the upper end and side of each bus bar assembly to be fixed to the battery pack. .
[98]
Although the fastening device 830 as described above may be located on one side close to the side edge of the heat insulating cover 800, it is preferable to exist at least on both sides of the heat insulating cover 800 in order to increase the fixing force.
[99]
The heat insulating cover 800 may be coupled to the heat insulating cover coupling portion of the bus bar assembly 500 . When there is a bus bar frame cover for fixing the bus bar assembly 500, such an insulating cover coupling part may exist in the bus bar frame cover. The heat insulating cover coupling part may be configured in a shape corresponding to the fastening device 830 .
[100]
The heat insulating cover 800 may have the same shape as described above, but any shape may be used as long as it can protect the blocking structure 400 .
[101]
The heat insulating cover 800 is preferably made of a heat insulating material.
[102]
This is to block the transfer of heat due to the occurrence of a fire. In addition, the insulating material may have chemical resistance.
[103]
By using a material having chemical resistance and heat insulation for the heat insulating cover 800, the sub-module 100 is further protected by primary protection with the heat insulating cover 800 and secondary protection with the blocking structure 400. can be more protected.
[104]
Any material that can be used for the battery may be used as the insulating material, but in consideration of the use of a battery pack, a material having a certain level of strength and not generating toxic substances is preferable.
[105]
An example of such a material is a compound containing silicon. Examples of the silicon-containing compound include mica and ceramics. In addition, it can be used as a material of the heat insulating cover 800 by coating a heat-resistant polymer such as nylon or polyethylene terephthalate so as not to react with chemicals.
[106]
Looking at the third preferred embodiment of the present invention, the heat insulating cover 800 of FIG. 8 has a form in which the sub-module 100 is coupled to cover the upper end and the side portion.
[107]
Although the fastening device 830 of the heat insulating cover 800 may include a separate heat insulating cover coupling part, the space of the coupling part 530 for coupling the bus bar assembly exists in the coupling part of the bus bar assembly 500 . can also be used.
[108]
The fastening device 830 may be coupled to a space existing in the groove portion of the coupling part 530 or may be coupled to fit the space to fix the heat insulating cover 800 .
[109]
10 is a modified example of the third preferred embodiment of the present invention.
[110]
A modified example of the third embodiment according to the present invention is a form in which the heat insulation cover 800 covers all of the connection bus bars 300 existing on the sub-module 100, or only a part of the connection bus bars 300 It may take the form of a cover. As mentioned above, when a fire occurs, it has a tendency to spread while returning to the ignition source, so that the entire connection bus bar 300 is covered to protect the connection bus bar 300 to prevent the spread of fire. .
[111]
In addition, in order to prevent the spread of fire due to a backfire phenomenon, the heat insulating cover 800 according to the present invention exists in parallel with the side cover 820 , and the connection bus bar 300 and the blocking structure 400 . It may further include a rear cover 840 to protect the rear of the. The rear cover 840 may be configured to protect a portion not protected by the connection bus bar 300 as shown in FIG. 10 , or may have a long plate shape to protect the connection bus bar 300 . In addition, the rear cover 840 according to the present invention may have a structure to protect the side portion close to the rear as shown in FIG. 10 . This is a structure to prepare for the case where the direction of the fire is partially deflected and returned.
[112]
Between the terminal part and the monoframe of Example (2) to which the barrier structure and the insulating cover according to the second embodiment of the present invention are applied and Comparative Example 26, in which only the insulating cover is present without the barrier structure according to the present invention The resistance value of is shown as a graph in FIG. 11 . The sub-module used at this time was a JH4 model commercially available from LG Chem, and mica was used as the material of the blocking structure and the insulation cover according to the present invention.
[113]
After disposing the sub-modules of Example (2) and Comparative Example (26) on both sides of the trigger sub-module (#33), a fire was caused in the trigger sub-module (#33). 12 is a schematic diagram showing the arrangement of the battery pack according to the second preferred embodiment of the present invention and the sub-modules for measuring the resistance of the comparative example. In this case, the resistance value was measured by measuring the resistance value between the terminal unit and the sub-module indicated by 1 and 2 in FIG. 12 . 11, the sub-module according to the present invention in Example (2) is not affected by fire and maintains a resistance value of 5.E+03Ω or more at the lowest, but the sub-module according to the comparative example is adjacent After a fire occurs in the module, after a certain period of time (560 seconds), the fire affects the adjacent module, and it can be seen that the resistance is converging to zero. Through this, when the blocking structure according to the present invention is provided, it can be seen that a constant resistance value, that is, a state of 3000Ω or more, is maintained, so that electricity due to ignition does not flow, and through this, fire transfer due to overcurrent does not occur.
[114]
In the present invention, a connector or a fuse may exist between the modules in order to prevent the transfer of fire due to overcurrent.
[115]
It may be a device using a battery pack corresponding to any one of the above-described ones as an energy source.
[116]
The device may be any one selected from the group consisting of a mobile phone, a tablet computer, a notebook computer, a power tool, a wearable electronic device, an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, and a power storage device.
[117]
As the specific part of the present invention has been described in detail above, for those of ordinary skill in the art, these specific descriptions are only preferred embodiments, and the scope of the present invention is not limited thereby. It is obvious to those skilled in the art that various changes and modifications can be made within the scope and spirit of the present invention, and it is natural that such variations and modifications fall within the scope of the appended claims.
[118]
[119]
[120]
-Description of symbols-
[121]
10, 100: sub-module
[122]
11: Cartridge
[123]
12: connection bus bar receiving part
[124]
20: terminal part
[125]
30, 300: connecting bus bar
[126]
40: bolt cover
[127]
400: blocking structure
[128]
410: superstructure
[129]
420: terminal protection
[130]
430: side structure
[131]
440: pollutant penetration prevention unit
[132]
450: fixed part
[133]
460: connection bus bar receiving part
[134]
50, 500: bus bar assembly
[135]
510: bus bar
[136]
520: bus bar frame
[137]
530: coupling part
[138]
600: pack case
[139]
700: side protection
[140]
800: insulation cover
[141]
810: top cover
[142]
820: side cover
[143]
830: fastening device
[144]
831: side fastening device
[145]
832: upper fastening device
[146]
833: fastening device fixing part
[147]
840: back cover
Industrial Applicability
[148]
The battery pack according to the present invention includes a blocking structure enclosing the terminal unit, the bus bar assembly, and the connecting bus bar of the sub module to prevent the transfer of current from the connecting portion of the terminal unit and the connecting bus bar to other parts of the sub module. Protects the exposed part of the module to prevent continuous damage to the sub-module by adjacent sub-modules.
[149]
The blocking structure is made of chemical-resistant and heat-insulating materials to prevent contamination of the terminal part and the connecting bus bar due to contamination caused by the damage of adjacent sub-modules. In addition, when a fire occurs in an adjacent sub-module, it is possible to immediately prevent the spread of fire by using an insulating material, and to protect the sub-module by preventing a certain amount of heat. This frees up time for the fire extinguishing system within the battery pack to operate or warns the user to prevent further damage.
[150]
In addition, it is possible to improve the safety of the entire battery through a simple configuration, such as providing a contaminant penetration prevention unit on the side portion of the blocking structure, or a heat insulating cover in addition to the blocking structure.
Claims
[Claim 1]
two or more sub-modules in which a plurality of unit cells including an electrode assembly and an electrode lead protruding from the electrode assembly are disposed; a pack case for accommodating the sub-module; a bus bar assembly including a bus bar for electrically connecting the electrode leads of the sub-module and a bus bar frame connected thereto; a connection bus bar for connecting the sub-modules; a terminal unit formed by gathering electrode leads electrically connected by the bus bar and connected to the connecting bus bar; and a blocking structure surrounding an upper end and a side surface of the connection bus bar of the terminal unit, the bus bar assembly, and a portion connected to the terminal unit. A battery pack containing
[Claim 2]
The battery pack of claim 1 , wherein the blocking structure is made of an insulating material having chemical resistance and thermal insulation properties.
[Claim 3]
The battery pack of claim 3 , wherein the insulating material includes silicate.
[Claim 4]
The battery pack of claim 3 , wherein the insulating material includes mica or ceramic.
[Claim 5]
The apparatus of claim 1 , wherein the blocking structure comprises: an upper structure formed in a shape corresponding to the bus bar assembly and positioned at an upper end of the bus bar assembly; a terminal protection part protruding from the upper structure in a shape corresponding to the terminal part and the connection bus bar; a side structure that further protects another sub-module facing portion of the bus bar frame; and a contaminant ingress prevention unit located under the upper structure and protecting both sides of the terminal unit and the connecting bus bar. A battery pack containing
[Claim 6]
The battery pack of claim 5 , wherein the contaminant penetration preventing unit is coupled to a space between the bus bar, the terminal unit, and the connection bus bar connected thereto.
[Claim 7]
The battery pack of claim 1 , wherein the blocking structure further comprises a heat insulating cover for protecting the blocking structure.
[Claim 8]
8. The device of claim 7, wherein the heat insulating cover comprises: a top cover disposed above the battery pack on which the bus bar assembly and the blocking structure are present; and a side cover present in the other sub-module facing portion of the bus bar assembly. A battery pack containing
[Claim 9]
The battery pack according to claim 7, wherein the heat insulating cover is made of a heat insulating material.
[Claim 10]
The battery pack of claim 9 , wherein the insulating material includes silicate.
[Claim 11]
The battery pack of claim 10 , wherein the insulating material includes mica or ceramic.
[Claim 12]
The battery pack according to claim 8, wherein the heat insulating cover completely covers the connection bus bar.
[Claim 13]
The battery pack of claim 8 , wherein the heat insulating cover further comprises a rear cover that is parallel to the side cover and protects a rear surface of the connection bus bar and the blocking structure.
[Claim 14]
A device using the battery pack according to any one of claims 1 to 13 as an energy source.
[Claim 15]
15. The method of claim 14, wherein the device is any one selected from the group consisting of a mobile phone, a tablet computer, a notebook computer, a power tool, a wearable electronic device, an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, and a power storage device. Device, characterized in that.