Secondary battery module

Abstract

To provide a secondary battery module that can prevent corrosion of a secondary battery cell by blocking the inflow of moisture from the outside.SOLUTION: A secondary battery module according to an embodiment of the present invention includes a plurality of cylindrical cells, a cell holder supporting the plurality of cylindrical cells, and a first case housing the plurality of cylindrical cells and the cell holder and having one open side, in which a potting material is applied to upper surfaces of the plurality of cylindrical cells and at least a portion of a surface of the cell holder to seal the plurality of cylindrical cells and the cell holder.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a secondary battery module, and more particularly, to a secondary battery module in which a potting member is applied to seal a plurality of cylindrical cells and a cell holder.

Background Art

[0002] Unlike a primary battery that cannot be charged, a secondary battery is a battery that can be charged and discharged. Low-capacity secondary batteries are used in portable small electronic devices such as smartphones, feature phones, laptop computers, digital cameras, and camcorders, and high-capacity secondary batteries are widely used as power sources for motor drives such as hybrid vehicles and electric vehicles and as batteries for power storage. Such secondary batteries include an electrode assembly composed of a positive electrode and a negative electrode, a case for housing the same, and electrode terminals connected to the electrode assembly.

[0003] When using a secondary battery, there is a risk of corrosion in the secondary battery cell due to factors such as long-term use, exposure to a high-temperature / high-humidity environment, temperature changes, and dew condensation. However, in the case of existing secondary battery modules, since the structure does not completely block the inflow of moisture from the external case, it is difficult to prevent corrosion of the secondary battery cell, and thus there is a problem of reducing long-term reliability. Therefore, a design of a secondary battery module for solving such problems is required.

[0004] The aforementioned information disclosed in the background art of such an invention is only for improving the understanding of the background of the present invention, and thus may include information that does not constitute the prior art.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The present disclosure relates to a secondary battery module in which a potting member is applied to the upper surfaces of a plurality of cylindrical cells and at least a part of the surface of a cell holder in order to solve the above problems.

[0007] However, the technical problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned should be clearly understood by those skilled in the art from the description of the invention described below.

Means for Solving the Problems

[0008] In a secondary battery module according to an embodiment of the present invention for solving the above technical problems, the secondary battery module includes a plurality of cylindrical cells, a cell holder that supports the plurality of cylindrical cells, and a first case that houses the plurality of cylindrical cells and the cell holder and has one surface open, and a potting member is applied to the upper surfaces of the plurality of cylindrical cells and at least a part of the surface of the cell holder so as to seal the plurality of cylindrical cells and the cell holder.

[0009] A secondary battery pack including the secondary battery module according to an embodiment of the present invention for solving the above technical problems is provided.

[0010] A vehicle including the secondary battery module according to an embodiment of the present invention for solving the above technical problems is provided.

Advantages of the Invention

[0011] According to various embodiments of the present disclosure, the height of the side surface of the lower case is formed such that the upper surface of the cylindrical cell is positioned lower than the height of the side surface of the lower case of the secondary battery module, so that the cylindrical cell can be accommodated in the lower case, and when the potting member is applied to the upper surface of the cylindrical cell, it is possible to prevent the potting member from overflowing from the lower case. In addition, it is also possible to guide an appropriate application amount by using the side surface of the lower case. Further, even with only the lower case of the secondary battery module, the cylindrical cell can be sealed using the potting member.

[0012] According to various embodiments of the present disclosure, the cylindrical cell is connected by wire bonding via a busbar and a wire, so that, unlike the case where the cylindrical cell is joined by resistance welding or laser welding, the cylindrical cell is not damaged. In addition, it is easy to secure the vent space of the cylindrical cell, and when ignition or heat generation occurs, the bonding wire serves as a fuse, so that heat propagation can be suppressed.

[0013] The cylindrical cell is coated using a material containing at least one of nickel (Ni) or tin (Sn), thereby preventing corrosion of the cylindrical cell.

[0014] The potting member injected / applied to the application surface may contain a heat insulating material. Thereby, even if one cylindrical cell catches fire, it is possible to prevent the fire from spreading to adjacent cylindrical cells.

[0015] When the potting member is applied, the potting member can also be applied to wire bonding, thereby preventing corrosion of the bonding wire as well.

[0016] Thereby, even without performing the tubing process on the cylindrical cell, corrosion of the cylindrical cell can be effectively prevented, thereby simplifying the process and reducing the cost associated with performing the tubing process.

[0017] As a result, the lower case and the cell holder are joined by the first uneven portion of the lower case and the second uneven portion of the cell holder, so that the lower case and the cell holder are firmly joined, and at the same time, the potting member seals more firmly.

[0018] However, the effects obtained by the present invention are not limited to the above-described effects, etc., and other technical effects, etc. not mentioned should be clearly understood by those skilled in the art from the description of the invention described below.

[0019] The following drawings, etc. attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention described later, serve to further understand the technical idea of the present invention. Therefore, the present invention should not be construed as being limited only to the matters described in such drawings.

Brief Description of the Drawings

[0020]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Modes for Carrying Out the Invention

[0021] <Summary of the Invention> In one embodiment of the present disclosure, a plurality of openings are formed in the cell holder such that at least a part of the upper surfaces of the plurality of cylindrical cells housed in the first case is exposed, and the potting member is applied to the plurality of openings to seal a gap between the plurality of cylindrical cells and the cell holder.

[0022] In one embodiment of the present disclosure, the potting member seals a gap between the first case and the cell holder.

[0023] In one embodiment of the present disclosure, the potting member is made of a heat insulating material.

[0024] In one embodiment of the present disclosure, the upper surfaces of the plurality of cylindrical cells are positioned lower than the height of the side surface of the first case.

[0025] In one embodiment of the present disclosure, a first uneven portion is formed on the side surface of the first case, a second uneven portion is formed on a portion of the cell holder that contacts the side surface of the first case, and the first case and the cell holder are coupled by the first uneven portion of the first case and the second uneven portion of the cell holder.

[0026] In one embodiment of the present disclosure, the first uneven portion includes a first recess and a first protrusion extending from the first recess, the second uneven portion includes a second recess and a second protrusion extending from the second recess, the first recess and the second protrusion are fitted together, and the first protrusion and the second recess are fitted together.

[0027] In one embodiment of the present disclosure, the first protrusion is formed so as to face parallel to the side surface of the first case, and the second protrusion is fitted to the first recess in a direction parallel to the first protrusion.

[0028] In one embodiment of the present disclosure, the secondary battery module further includes a battery management system (BMS), and the battery management system and the plurality of cylindrical cells are connected by wire bonding.

[0029] In one embodiment of the present disclosure, at least a part of the wire bonding is located inside the applied potting member.

[0030] In one embodiment of the present disclosure, the secondary battery module further includes a bus bar electrically connected to the plurality of cylindrical cells, and the plurality of cylindrical cells are connected to the bus bar by wire bonding.

[0031] In one embodiment of the present disclosure, the cell holder includes a guide portion for guiding the bus bar.

[0032] In one embodiment of the present disclosure, the wire bonding is located inside the applied potting member.

[0033] In one embodiment of the present disclosure, a cell support portion for supporting the plurality of cylindrical cells is formed on the bottom surface inside the first case.

[0034] In one embodiment of the present disclosure, the cell support portion includes a plurality of grooves for accommodating and supporting at least a part of the plurality of cylindrical cells, and at least a part of the plurality of cylindrical cells includes the lower surface of each of the plurality of cylindrical cells.

[0035] In one embodiment of the present disclosure, the cell holder includes a plurality of fixing portions for fixing the plurality of cylindrical cells, and the arrangement of the plurality of grooves corresponds to the arrangement of the plurality of fixing portions.

[0036] In one embodiment of the present disclosure, the secondary battery module further includes a second case that seals the open surface of the first case by being coupled to the first case.

[0037] In one embodiment of the present disclosure, each of the plurality of cylindrical cells is coated using a material containing at least one of nickel (Ni) or tin (Sn).

[0038] <Detailed Description of the Invention> Hereinafter, based on the accompanying drawings, preferred embodiments of the present disclosure will be described in detail. First, the terms and words used in this specification and the claims should not be construed as being limited to their ordinary and dictionary meanings. In accordance with the principle that the inventor can appropriately define the concept of the terms in order to best explain his invention, they must be construed in a meaning and concept consistent with the technical idea of the present invention. Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are only some preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention. At the time of this application, there may be various equivalents and modifications that can replace these.

[0039] Also, as used in this specification, "comprise", "include" and / or "comprising", "including" identify the presence of the recited shape, number, step, operation, member, element and / or group, and do not exclude the presence or addition of one or more other shapes, numbers, operations, members, elements and / or groups. Also, when describing embodiments of the present invention, "can be" and "can be" can include "one or more embodiments of the present invention".

[0040] Also, to assist in understanding the invention, the accompanying drawings are not shown at actual scale, and the dimensions of some components can be shown exaggerated. Also, in different embodiments, the same reference numerals are assigned to the same components.

[0041] A reference that two comparison targets are "identical" means "substantially identical". Therefore, being substantially identical can include cases with a deviation regarded as a low level in the art, for example, a deviation within 5%. Also, in a given region, that a certain parameter is uniform can mean being uniform from an average perspective.

[0042] The terms such as first, second, etc. are used to describe various components, but of course these components etc. are not limited by these terms. These terms etc. are only used to distinguish one component from another component, and of course, unless otherwise stated, the first component can be the second component.

[0043] Throughout the specification, unless otherwise stated, each component can be singular or plural.

[0044] That any configuration is arranged "above (or below)" a component or "on (or under)" a component means that not only is any configuration arranged in contact with the upper surface (or lower surface) of the component, but other configurations can also be interposed between the component and any configuration arranged above (or below) the component.

[0045] Also, when a certain component is described as being "coupled", "connected", or "joined" to another component, it should be understood that these components etc. can be directly coupled or connected to each other, but other components can also "intervene" between the components, or each component can be "coupled", "connected", or "joined" to another component through other components.

[0046] Also, when a certain part is said to be electrically coupled to another part, this includes not only the case of being directly coupled, but also the case of being coupled with other elements sandwiched in between.

[0047] Throughout the specification, when "A and / or B" is used, this means A, B, or A and B, unless otherwise stated. That is, "and / or" includes all combinations or any combination of the listed multiple items. When "C to D" is used, this means C or more and D or less, unless otherwise stated.

[0048] In the present disclosure, when a component is described as "contacting", "abutting", or "fitting" with another component, or in a similar meaning, it should be understood that a gap may exist in part or in whole of the region where the components are adjacent to each other.

[0049] FIG. 1 is a diagram showing an example of a secondary battery module 100 according to an embodiment of the present disclosure. The secondary battery module 100 can include a case 110, 120 that houses a plurality of secondary battery cells (e.g., cylindrical cells) and a plurality of secondary battery cells.

[0050] The secondary battery cells included in the secondary battery module 100 generate a large amount of heat during charging / discharging. The generated heat is accumulated in the secondary battery cells and accelerates the deterioration of the secondary battery cells. Therefore, the secondary battery pack including the secondary battery module 100 further includes a cooling member to suppress the deterioration of the secondary battery cells. The cooling member is provided at the lower part of the accommodation space including the secondary battery cells, but is not limited thereto, and may be provided at the upper part or the side surface according to the secondary battery pack.

[0051] Exhaust gas in the secondary battery cell generated under abnormal operating conditions known as thermal runaway or thermal event in each secondary battery cell can be discharged to the outside of the secondary battery cell. The secondary battery pack or the secondary battery module 100 can include an exhaust port or the like for discharging the exhaust gas in order to suppress damage to the secondary battery pack or the module 100 caused by the exhaust gas.

[0052] A secondary battery pack (or secondary battery module 100) can include a secondary battery and a battery management system (BMS) for managing the secondary battery. The secondary battery management device can include a detection device, a balancing device, and a control device. The secondary battery module 100 can include a plurality of cells connected in series or parallel to each other. The secondary battery modules 100 can be connected in series or parallel to each other.

[0053] The detection device can sense the state of the secondary battery (such as voltage, current, temperature, etc.) and detect state information indicating the state of the secondary battery. The detection device can detect the voltage of each cell or each secondary battery module 100 constituting the secondary battery. The detection device can also detect the current flowing through each secondary battery module 100 constituting the secondary battery module or the secondary battery pack. The detection device can also detect the temperature of the cell and / or module 100 at at least one point of the secondary battery and / or the ambient temperature.

[0054] The balancing device can perform a balancing operation on the secondary battery modules 100 and / or cell groups constituting the secondary battery. The control device can receive state information (such as voltage, current, temperature, etc.) of the secondary battery module 100 from the detection device. Based on the state information received from the detection device, the control device can monitor and calculate the state (such as voltage, current, temperature, SOC (State Of Charge), SOH (State Of Health), etc.) of the secondary battery module 100. Also, based on the state monitoring result, the control device can perform control functions (such as temperature control, balance control, charge and discharge control, etc.), protection functions (such as over-discharge prevention, over-charge prevention, over-current prevention, short circuit, digestion functions, etc.), etc. Also, the control device can perform a function of wired or wireless communication with external devices (such as a host controller, a vehicle, a charger, a PCS, etc.) of the secondary battery pack.

[0055] The control device can also control the charge and discharge operation and the protection operation of the secondary battery. For this purpose, the control device can include a charge and discharge control unit, a balance control unit, and a protection unit.

[0056] The battery management system is a system that monitors the state of the secondary battery and performs functions of diagnosis and control, communication, and protection. It can calculate the charge and discharge state, calculate the life or state of health (SOH) of the secondary battery, cut off the power of the secondary battery (relay control) when necessary, perform thermal management (such as cooling and heating) control, perform a high-voltage interlock function, and detect or calculate the insulation and short-circuit states.

[0057] The relay can be a mechanical contact that is turned on and off by the magnetic force of a coil, or a semiconductor switch such as a MOSFET (Metal Oxide Semiconductor Field Effect Transistor).

[0058] Relay control is a function of cutting off the power supply from the secondary battery when problems occur in the vehicle and the secondary battery system. It can include one or more relays and a pre-charge relay at each of the positive terminal and the negative terminal.

[0059] Pre-charge control has a risk of generating an inrush current in the high-voltage capacitor on the input side of the inverter when connecting the load of the secondary battery. Therefore, in order to prevent the generation of the inrush current, when starting the vehicle, the pre-charge relay can be operated before connecting the main relay to connect to the pre-charge resistor.

[0060] High-voltage interlock is a circuit that senses using a small signal to confirm whether all high-voltage components are connected in all automotive systems. If an open occurs at even one location on all loops, it can have a function of forcibly opening the relay.

[0061] FIG. 2 is an exploded perspective view of a secondary battery module 100 according to an embodiment of the present disclosure. The secondary battery module 100 may include, but is not limited to, a cylindrical cell 140, a first case 110 positioned below the cylindrical cell 140, a second case 120 positioned above the cylindrical cell 140 and coupled to the first case 110, a cell monitoring unit 130, a cell holder 150 for supporting the cylindrical cell, and a busbar 160.

[0062] The cylindrical cell 140 may refer to a plurality of cylindrical cells included in the secondary battery module 100 unless otherwise limited, and the detailed structure of the cylindrical cell 140 will be described in detail with reference to FIG. 3 later.

[0063] The first case 110 has one open side and can accommodate the cylindrical cell 140, the cell holder 150, and the busbar 160. In one embodiment, when the cylindrical cell 140 and the first case 110 are coupled, the cylindrical cell 140 and the first case 110 can be manufactured such that the upper surface of the cylindrical cell 140 is positioned lower than the height of the side surface of the first case 110. Thereby, the cylindrical cell 140 can be accommodated in the first case 110, and the cylindrical cell 140 can be blocked from the outside and sealed by a potting member described later with reference to FIG. 4. Additionally, the first case 110 can accommodate at least a part of the wire 154.

[0064] A cell support portion for supporting the cylindrical cell 140 can be formed on the bottom surface inside the first case 110. Specifically, the cell support portion may include a groove 112 that accommodates and supports at least a part of the cylindrical cell 140. For example, the groove 112 can accommodate and support a part of the cylindrical cell 140 including the lower surface of the cylindrical cell 140.

[0065] The second case 120 is coupled to the first case 110 and can seal the open side of the first case 110. Thereby, corrosion of the cylindrical cell 140 can be prevented by blocking the cylindrical cell 140 accommodated in the first case 110 from external air, moisture, etc.

[0066] The cell monitoring unit 130 can sense the state (voltage, current, temperature, etc.) of the secondary battery and detect state information indicating the state of the secondary battery. The cell monitoring unit 130 can detect the voltage of each cell or each secondary battery module constituting the secondary battery. The cell monitoring unit 130 can also detect the current flowing through the secondary battery module. The cell monitoring unit 130 can also detect the temperature of the cell and / or module and / or the ambient temperature at at least one point of the secondary battery.

[0067] Additionally, the cell monitoring unit 130 can perform a balancing operation of the secondary battery modules and / or cell groups constituting the secondary battery.

[0068] The cell holder 150 can support the cylindrical cell 140. Specifically, the cell holder 150 can support the upper part (+z direction) of each of the cylindrical cells 140.

[0069] An opening 152 can be formed in the cell holder 150 so that at least a part of the upper surface of the cylindrical cell 140 housed in the first case 110 is exposed. As will be described later with reference to FIG. 6 and the like, by applying a potting member to the opening 152, the gap between the cylindrical cell 140 and the cell holder 150 can be sealed.

[0070] The cell holder 150 includes a fixing part for fixing the cylindrical cell 140, and the arrangement of the grooves 112 can correspond to the arrangement of the fixing part. Thereby, the cylindrical cell 140 can be supported in the vertical direction (z direction) by the grooves 112 and the fixing part of the cell holder 150.

[0071] The bus bar 160 can be located above the cell holder 150, and the cell holder 150 can include a guide part for guiding the bus bar 160. The bus bar 160 can connect the cylindrical cells 140 in series and / or in parallel with each other.

[0072] The bus bar 160 can be electrically connected to the cylindrical cell 140. For example, the cylindrical cell 140 can be connected to the bus bar 160 by wire bonding via a wire 154. This way, unlike the case of joining the cylindrical cell 140 by resistance welding or laser welding, the cylindrical cell 140 is not damaged. Also, it is easy to secure the vent space of the cylindrical cell 140, and when ignition or heat generation occurs, the bonding wire can act as a fuse to suppress the propagation of heat.

[0073] FIG. 3 is a diagram showing an example of the cylindrical cell 140 according to an embodiment of the present disclosure. As shown in FIG. 3, the cylindrical cell 140 according to various embodiments of the present invention can include a cylindrical can 142, an electrode assembly, and a cap assembly 149. Also, the cylindrical cell 140 can further include a center pin, if necessary. Also, in the cylindrical cell 140 according to an embodiment of the present invention, since the cap assembly 149 also performs a current interruption operation, it can also be referred to as a current interrupt device, if necessary.

[0074] The cylindrical can 142 can include a substantially circular bottom surface portion and a cylindrical side wall extending upward from around the bottom surface portion with a certain length. During the manufacturing process of the secondary battery, the upper part of the cylindrical can 142 is open. Therefore, during the assembly process of the secondary battery, the electrode assembly and the center pin can be inserted into the cylindrical can 142 together with the electrolytic solution. The cylindrical can 142 can be manufactured, for example, from steel, stainless steel, aluminum, an aluminum alloy, or an equivalent thereof, but is not limited thereto.

[0075] Also, the cylindrical can 142 can include a beading part 144 that is recessed inward at its lower part around the cap assembly 149 and a crimping part 146 that is bent inward at its upper part so that the cap assembly 149 does not deviate to the outside.

[0076] The electrode assembly can be housed inside the cylindrical can 142. The electrode assembly includes a negative electrode plate in which a negative electrode active material (e.g., graphite or carbon) is coated on a negative electrode current collector plate, a positive electrode plate in which a positive electrode active material (e.g., transition metal oxide (such as LiCoO2, LiNiO2, LiMn2O4)) is coated on a positive electrode current collector plate, and a separator located between the negative electrode plate and the positive electrode plate to prevent short circuits and allow only the movement of lithium ions. Further, the negative electrode plate, the positive electrode plate, and the separator are wound in a substantially cylindrical shape. Here, for example, the negative electrode current collector plate can be made of copper (Cu) foil, the positive electrode current collector plate can be made of aluminum (Al) foil, and the separator can be made of polyethylene (PE) or polypropylene (PP), but it is not limited thereto.

[0077] Also, a negative electrode tab protruding downward with a certain length can be welded to the negative electrode plate, and a positive electrode tab protruding upward with a certain length can be welded to the positive electrode plate, but the opposite is also possible. Together, for example, the negative electrode tab can be made of copper (Cu) or nickel (Ni), and the positive electrode tab can be made of aluminum (Al), but it is not limited thereto.

[0078] Also, the negative electrode tab of the electrode assembly can be welded to the bottom of the cylindrical can 142. Thus, the cylindrical can 142 can operate as a negative electrode. Of course, conversely, the positive electrode tab can be welded to the bottom of the cylindrical can 142, and in such a case, the cylindrical can 142 can operate as a positive electrode.

[0079] Together, a first insulating plate coupled to the cylindrical can 142 and having a first hole formed in the center and a second hole formed outside thereof can be interposed between the electrode assembly and the bottom. Such a first insulating plate serves to prevent the electrode assembly from coming into electrical contact with the bottom of the cylindrical can 142. In particular, the first insulating plate serves to prevent the positive electrode plate from coming into electrical contact with the bottom in the electrode assembly. Here, the first hole serves to allow gas to quickly move upward through the center pin if a large amount of gas is generated due to an abnormality in the secondary battery, and the second hole serves to allow the negative electrode tab to penetrate and be welded to the bottom.

[0080] Further, a second insulating plate coupled to the cylindrical can 142 and having a first hole formed at the center and a plurality of second holes formed outside thereof may be interposed between the electrode assembly and the cap assembly 149. Such a second insulating plate serves to prevent the electrode assembly from being in electrical contact with the cap assembly 149. In particular, the second insulating plate serves to prevent the negative electrode plate from being in electrical contact with the cap assembly 149 in the electrode assembly. Here, the first hole serves to allow gas to quickly move to the cap assembly 149 if a large amount of gas is generated due to an abnormality of the secondary battery, and the second holes serve to allow the positive electrode tab to penetrate and be welded to the cap assembly 149. Also, the remaining second holes serve to allow the electrolyte to quickly flow into the electrode assembly during the electrolyte injection process.

[0081] Together, the diameters of the first holes of the first insulating plate and the second insulating plate are formed to be smaller than the diameter of the center pin, so that the center pin is prevented from being in electrical contact with the bottom of the cylindrical can 142 or the cap assembly 149 due to an external impact.

[0082] The center pin has a hollow circular pipe shape and can be coupled to the approximate center of the electrode assembly. Such a center pin can be made of, for example, steel, stainless steel, aluminum, aluminum alloy, or polybutylene terephthalate, but is not limited thereto. Such a center pin serves to suppress deformation of the electrode assembly during charging and discharging of the secondary battery and serves as a gas movement passage inside the secondary battery. Of course, such a center pin can be omitted depending on the case.

[0083] The cap assembly 149 may include a top plate 148, a middle plate, an insulating plate, and a bottom plate.

[0084] The middle plate is located below the top plate 148 and can have a substantially flat form.

[0085] The insulating plate can be formed in a circular ring shape with a certain width when viewed from below. Also, such an insulating plate serves to insulate the middle plate and the bottom plate from each other. The insulating plate is, for example, interposed between the middle plate and the bottom plate and ultrasonic welding is performed, but it is not limited thereto.

[0086] The cylindrical cell 140 can be coated using a material containing at least one of nickel (Ni) or tin (Sn). Thereby, corrosion of the cylindrical cell 140 can be prevented. Without being limited thereto, the cylindrical cell 140 can be coated using polymer materials such as PVDF (Polyvinylidene fluoride), PET (Polyethylene terephthalate), PTFE (Polytetrafluoroethylene), rubber materials, ceramic materials such as aluminum oxide and titanium oxide, and the like.

[0087] FIG. 4 is a diagram showing an example in which a potting member according to an embodiment of the present disclosure is applied using an application device 400.

[0088] The potting member can be injected / applied to the application surface 420 where at least a part of the upper surface of the cylindrical cell and the surface of the cell holder are exposed to the outside. The application surface 420 is shown as flat, but this is an omission of the detailed structure for the sake of convenience of explanation. The application device 400 is shown as injecting / applying the potting member in a direction perpendicular to the application surface 420, but it is not limited thereto.

[0089] The potting member applied by the coating device 400 can be made of epoxy resin, silicon material, polyurethanes, acrylic resin, or a combination thereof, etc., but is not limited thereto. In one embodiment, the potting member injected / applied to the coating surface 420 can include a heat insulating material. Thereby, even if one cylindrical cell catches fire, it can be prevented from spreading the fire to adjacent cylindrical cells. Additionally or alternatively, the potting member can include a flame retardant material.

[0090] By injecting / applying the potting member to the coating surface 420 by the coating device 400, the cylindrical cell 140 and the cell holder 150 can be blocked from the outside and sealed. The potting member can be injected / applied up to the height of the lower case 410 at most. The lower case 410 can guide the injection amount of the potting member.

[0091] FIG. 5 is a diagram showing an example in which a potting member 540 according to an embodiment of the present disclosure is applied. The cylindrical cell 520 can be supported by the groove 512 of the lower case 510 and the cell holder 530 constituting the secondary battery module, and the potting member 540 can be applied to seal the cylindrical cell 520 and the cell holder 530. In one embodiment, the potting member 540 can be applied to the upper surface of the cylindrical cell 520 and at least a part of the surface of the cell holder 530. The potting member 540 can be applied in parallel to the open surface on the open surface of the lower case 510.

[0092] As shown in the figure, the upper surface of the cylindrical cell 520 (and / or the cell holder 530) may be positioned lower than the height of the side surface of the lower case 510. Thereby, when applying the potting member 540 to the upper surface of the cylindrical cell 520, it is possible to prevent the potting member 540 from overflowing from the lower case 510, and at the same time, it is possible to guide an appropriate application amount using the side surface of the lower case 510. Also, even with only the lower case 510 of the secondary battery module, the cylindrical cell 520 can be sealed using the potting member 540.

[0093] Thereby, even if the tubing process is not performed on the cylindrical cell 520, corrosion of the cylindrical cell 520 can be effectively prevented, so that the process can be simplified and at the same time, the cost associated with performing the tubing process can be reduced. However, this does not exclude the performance of the tubing process, and by additionally performing the tubing process, corrosion of the cylindrical cell 520 can be more effectively prevented. Additionally, when an upper case (not shown) of the secondary battery module is further coupled, the cylindrical cell 520 can be sealed more firmly.

[0094] The cylindrical cell 520 can be electrically connected to a bus bar (not shown), and the cylindrical cell 520 can be connected to the bus bar by wire bonding. Also, the cylindrical cell 520 can be connected to a Battery Management System (BMS) 550 by wire bonding.

[0095] At least a part of the wire bonding connected to the bus bar and / or the wire bonding connected to the battery management system 550 may be located inside the potting member 540. That is, when the potting member 540 is applied, the potting member 540 can also be applied to the wire bonding, thereby preventing corrosion of the bonding wire as well.

[0096] FIG. 6 is a diagram showing an example in which the cylindrical cell 520 is sealed by the potting member 540 according to an embodiment of the present disclosure. In FIGS. 6 and 7, the gaps shown between the cylindrical cell 520 and the cell holder 530 and between the lower case 510 and the cell holder 530 may be somewhat exaggerated for the purpose of facilitating understanding of the invention, and the gaps exist only in a part of the region where the components are adjacent to each other, and FIGS. 6 and 7 should be understood as showing cross-sections of the regions where the gaps exist.

[0097] An opening 532 is formed in the cell holder 530 so that at least a part of the upper surface of the cylindrical cell 520 is exposed, and the potting member 540 can be applied to the opening 532 formed in the cell holder 530. Since the potting member 540 can be liquid before curing, the applied potting member 540 can flow into the gap between the cylindrical cell 520 and the cell holder 530 and then cure to seal the gap between the cylindrical cell 520 and the cell holder 530.

[0098] Also, the potting member 540 can seal the gap between the lower case 510 and the cell holder 530. The potting member 540 is applied between the side surface of the lower case 510 and the cell holder 530, and the potting member 540 can flow into the gap between the lower case 510 and the cell holder 530 and then cure to seal the gap between the lower case 510 and the cell holder 530.

[0099] Thereby, the potting member 540 can seal the cylindrical cell 520 and the cell holder 530 on the open surface of the lower case 510.

[0100] FIG. 7 is a diagram showing an example in which a cell holder 530 according to an embodiment of the present disclosure is coupled to a lower case 510. In one embodiment, a first concavo-convex portion is formed on a side surface of the lower case 510, and a second concavo-convex portion is formed on a portion of the cell holder 530 that contacts the side surface of the lower case 510. The lower case 510 and the cell holder 530 can be coupled by the first concavo-convex portion of the lower case 510 and the second concavo-convex portion of the cell holder 530.

[0101] For example, the first concavo-convex portion includes a first concave portion 516 and a first protruding portion 514 extending from the first concave portion 516. The first protruding portion 514 can be formed so as to face parallel to the side surface 518 of the lower case 510.

[0102] Similarly, the second concavo-convex portion can include a second concave portion 536 and a second protruding portion 534 extending from the second concave portion 536. The first concave portion 516 and the second protruding portion 534 are fitted, and the first protruding portion 514 and the second concave portion 536 are fitted. The second protruding portion 534 is fitted into the first concave portion in a direction parallel to the first protruding portion 514. Thereafter, a potting member 540 can be applied to the upper surface of the cylindrical cell 520 and at least a part of the surface of the cell holder 530.

[0103] Thereby, the lower case 510 and the cell holder 530 are coupled by the first concavo-convex portion of the lower case 510 and the second concavo-convex portion of the cell holder 530, so that the lower case 510 and the cell holder 530 are more firmly coupled, and at the same time, the sealing by the potting member 540 is more firmly performed.

[0104] The concavo-convex structure of the lower case 510 and the cell holder 530 is not limited to this, and any structure that can couple the lower case 510 and the cell holder 530 may be used.

[0105] FIG. 8 is a schematic side view of a vehicle 800 according to an embodiment of the present disclosure. FIG. 8 shows a vehicle body and vehicle parts including a secondary battery pack 830 according to a preferred embodiment of the present disclosure. The secondary battery pack 830 can include a secondary battery module according to the present disclosure (for example, the secondary battery module 100 in FIGS. 1 and 2).

[0106] In FIG. 8, the secondary battery pack 830 can include a secondary battery pack cover 834 that is part of the vehicle underbody 820 and a pack frame 835 disposed below the vehicle underbody 820. The pack frame 835 and the secondary battery pack cover 834 can be a structure integrally formed with the bottom 810 of the vehicle.

[0107] The vehicle underbody 820 separates the interior and exterior of the vehicle, and the pack frame 835 can be disposed outside the vehicle.

[0108] The vehicle 800 can be configured by coupling additional parts such as a hood in front of the vehicle and fenders located in front and rear of the vehicle to the vehicle body.

[0109] The vehicle 800 can further include the bottom 810 of the vehicle and the secondary battery pack cover 834, which are parts of the vehicle body including the secondary battery pack 830 having the pack frame 835.

[0110] As described above, the present invention has been described with reference to limited embodiments and drawings, but is not limited thereto. Of course, various modifications and variations can be made by those having ordinary knowledge in the technical field to which the present invention pertains within the equivalent scope of the technical idea and claims of the present invention.

Description of Reference Numerals

[0111] 100 Secondary battery module 110 First case 120 Second case 130 Cell monitoring unit 140 Cylindrical cell 142 Cylindrical can 144 Beading part 146 Gripping part 148 Top plate 149 Cap assembly 150 Cell holder 152 Opening 154 Wire 160 Bus bar

Claims

1. In a secondary battery module, a plurality of cylindrical cells; a cell holder for supporting the plurality of cylindrical cells; a first case that houses the plurality of cylindrical cells and the cell holder and has one side open; comprising A secondary battery module, wherein a potting member is applied to the upper surfaces of the plurality of cylindrical cells and at least a part of the surface of the cell holder so as to seal the plurality of cylindrical cells and the cell holder.

2. The cell holder is formed with a plurality of openings so that at least a part of the upper surfaces of the plurality of cylindrical cells housed in the first case is exposed, The potting member is applied to the plurality of openings to seal a gap between the plurality of cylindrical cells and the cell holder. The secondary battery module according to claim 1.

3. The potting member seals a gap between the first case and the cell holder. The secondary battery module according to claim 1.

4. The potting member is made of a heat insulating material. The secondary battery module according to claim 1.

5. The upper surfaces of the plurality of cylindrical cells are positioned lower than the height of the side surface of the first case. The secondary battery module according to claim 1.

6. A first uneven portion is formed on the side surface of the first case, A second uneven portion is formed on a portion of the cell holder that contacts the side surface of the first case, The first case and the cell holder are coupled by the first uneven portion of the first case and the second uneven portion of the cell holder. The secondary battery module according to claim 1.

7. The first uneven portion includes a first recess and a first protrusion extending from the first recess, The second uneven portion includes a second recess and a second protrusion extending from the second recess, The first recess and the second protrusion are fitted, and the first protrusion and the second recess are fitted. The secondary battery module according to claim 6.

8. The first protrusion is formed so as to face parallel to the side surface of the first case, The second protrusion is fitted to the first recess in a direction parallel to the first protrusion. The secondary battery module according to claim 7.

9. The secondary battery module further includes a battery management system, The secondary battery module according to claim 1, wherein the battery management system and the plurality of cylindrical cells are connected by wire bonding.

10. The secondary battery module according to claim 9, wherein at least a part of the wire bonding is located inside the applied potting member.

11. The secondary battery module further includes a bus bar electrically connected to the plurality of cylindrical cells, The secondary battery module according to claim 1, wherein the plurality of cylindrical cells are connected to the bus bar by wire bonding.

12. The secondary battery module according to claim 11, wherein the cell holder includes a guide portion for guiding the bus bar.

13. The secondary battery module according to claim 12, wherein the wire bonding is located inside the applied potting member.

14. The secondary battery module according to claim 1, wherein a cell support portion for supporting the plurality of cylindrical cells is formed on the bottom surface inside the first case.

15. The cell support portion includes a plurality of grooves for accommodating and supporting at least a part of the plurality of cylindrical cells, The secondary battery module according to claim 14, wherein at least a part of the plurality of cylindrical cells includes the lower surface of each of the plurality of cylindrical cells.

16. The cell holder includes a plurality of fixing portions for fixing the plurality of cylindrical cells, The secondary battery module according to claim 15, wherein the arrangement of the plurality of grooves corresponds to the arrangement of the plurality of fixing portions.

17. The secondary battery module according to claim 1, further includes a second case that seals the opened surface of the first case when combined with the first case.

18. Each of the plurality of cylindrical cells is coated using a material containing at least one of nickel (Ni) or tin (Sn). The secondary battery module according to claim 1.

19. A secondary battery pack including the secondary battery module according to claim 1.

20. A vehicle including the secondary battery module according to claim 1.

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