Battery Module, Battery Pack, and Vehicle

Abstract

A battery module according to one embodiment of the present invention may include a plurality of battery cells; a polymer member disposed between the plurality of battery cells; and a filler disposed inside the polymer member and having an empty space inside.

Description

Technology Field

[0001] The present invention relates to a battery module, a battery pack, and an automobile, and more specifically, to a battery module with reduced manufacturing costs and improved safety against fire. Background Technology

[0002] Currently commercialized rechargeable batteries include nickel-cadmium, nickel-hydrogen, nickel-zinc, and lithium-ion batteries. Among these, lithium-ion batteries are gaining attention for their advantages, such as the ability to freely charge and discharge with almost no memory effect compared to nickel-based batteries, a very low self-discharge rate, and high energy density.

[0003] In addition, lithium secondary batteries can be classified according to the shape of the casing into cylindrical battery cells in which the electrode assembly is embedded in a metal can and pouch-type secondary batteries in which the electrode assembly is embedded in a pouch of aluminum laminate sheet.

[0004] In particular, the demand for high-capacity battery modules applied to electronic devices, automobiles, etc., has recently been increasing. Such high-capacity battery modules may be equipped with multiple battery cells, such as multiple cylindrical battery cells.

[0005] However, in such battery modules, if thermal runaway, fire, or explosion occurs in a part of a plurality of cylindrical battery cells, high-temperature heat, fragments of the electrode assembly, flames, and gases are emitted, which can raise the temperature of adjacent battery cells. Consequently, there was a problem in that thermal runaway or fire could spread to adjacent battery cells, causing a larger secondary fire or explosion, thereby exacerbating the damage.

[0006] Furthermore, the space between multiple cylindrical battery cells or between the module case and the cells is often very narrow, posing a problem of high vulnerability to heat or flame propagation between the cells. Additionally, due to such confined spaces, there were significant limitations in providing separate components to prevent heat or flame propagation. Moreover, while conventional battery modules have attempted to incorporate specific materials to prevent internal heat or flame propagation, the high cost of such materials remains a concern. Consequently, conventional battery modules have faced significant difficulties in efficiently ensuring safety against heat or fire. The problem to be solved

[0007] Accordingly, the present invention is devised to solve the above-mentioned problems and aims to provide a battery module that can efficiently ensure safety against heat, fire, etc., a battery pack including the same, and an automobile, etc.

[0008] Other objects and advantages of the present invention may be understood from the following description and will become more clearly apparent from the embodiments of the present invention. Furthermore, it will be readily apparent that the objects and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims. means of solving the problem

[0009] A battery module according to one aspect of the present invention for achieving the above-mentioned purpose may include: a plurality of battery cells; a polymer member disposed between the plurality of battery cells; and a filler disposed inside the polymer member and having an empty space inside.

[0010] In addition, the battery module may further include a case accommodating the plurality of battery cells, the polymer member, and the filler.

[0011] In addition, the polymer member may include a resin.

[0012] In addition, the polymer member may have a cured form.

[0013] In addition, the above filler may be provided in multiple quantities and dispersed within the polymer member.

[0014] In addition, the above filler may include a plastic material.

[0015] In addition, the above filler may have a spherical shape.

[0016] In addition, the diameter of the above filler may be 1 µm to 1 mm.

[0017] In addition, the above filler may include a material having elasticity.

[0018] And, a battery pack according to another aspect of the present invention for achieving the above-mentioned purpose includes a battery module according to the present invention.

[0019] In addition, an automobile according to another aspect of the present invention for achieving the above-mentioned purpose includes a battery module according to the present invention. Effects of the invention

[0020] According to one aspect of the present invention, a battery module with excellent safety and economic efficiency can be secured.

[0021] In particular, according to one embodiment of the present invention, by including a polymer member and a filler inside the module, performance such as preventing heat or flame propagation and preventing explosion can be more effectively secured.

[0022] Furthermore, the polymer component can act as a barrier to prevent the flame from spreading to adjacent battery cells in the event that any one of the multiple battery cells ignites and explodes. Accordingly, it can effectively prevent multiple battery cells from exploding in a chain reaction or the spread of fire.

[0023] In addition, according to one aspect of the present invention, such heat / flame propagation prevention performance can be secured at a relatively low cost, thereby enabling the realization of a battery module or battery pack with excellent safety and economic efficiency.

[0024] In particular, according to one embodiment of the present invention, when a silicone resin (silicone polymer) is injected into the pack as a polymer member to delay ignition or explosion of the battery cell, the amount of silicone resin can be reduced through a filler.

[0025] Accordingly, according to this aspect of the present invention, the amount of relatively expensive silicone resin can be reduced, thereby reducing manufacturing costs.

[0026] In addition, according to one aspect of the present invention, if the density of the filler is lower than that of the silicone resin, it may be advantageous for reducing the weight of the battery module. Brief explanation of the drawing

[0027] The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the detailed description of the invention provided below; therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings. FIG. 1 is a perspective view schematically showing a battery module according to one embodiment of the present invention. FIG. 2 is an exploded perspective view schematically showing the separated parts of a battery module according to one embodiment of the present invention. FIG. 3 is a diagram schematically showing the internal configuration of a battery module according to one embodiment of the present invention. FIG. 4 is a diagram schematically showing the internal configuration of a battery module according to another embodiment of the present invention. FIG. 5 is a diagram schematically showing a part of the internal configuration of a battery module according to another embodiment of the present invention. FIG. 6 is a cross-sectional view schematically showing the particle composition of a filler included in a battery module according to another embodiment of the present invention. FIG. 7 is a cross-sectional view schematically showing the particle composition of a filler included in a battery module according to another embodiment of the present invention. FIG. 8 is a cross-sectional view schematically showing the particle composition of a filler included in a battery module according to another embodiment of the present invention. FIG. 9 is a cross-sectional view schematically showing the particle composition of a filler included in a battery module according to another embodiment of the present invention. FIG. 10 is a diagram schematically showing the particle composition of a filler included in a battery module according to another embodiment of the present invention. FIG. 11 is a cross-sectional view schematically showing the particle composition of a filler included in a battery module according to another embodiment of the present invention. Specific details for implementing the invention

[0028] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, and should be interpreted in a meaning and concept consistent with the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0029] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention; thus, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

[0030] In addition, although terms indicating directions such as up, down, left, right, front, and back may be used in this specification, these terms are used merely for convenience of explanation and may vary depending on the location of the object or the position of the observer, it is obvious to those skilled in the art of this invention.

[0032] FIG. 1 is a schematic perspective view of a battery module according to an embodiment of the present invention. FIG. 2 is an exploded perspective view schematically showing some components of a battery module according to an embodiment of the present invention separated. FIG. 3 is a schematic diagram showing the internal configuration of a battery module according to an embodiment of the present invention. In particular, FIG. 3 can be described as a diagram showing the cross-sectional configuration along the line C-C' of FIG. 1. Additionally, in FIG. 2, the polymer member and the filler are shown in an excluded form for convenience of illustration.

[0033] Referring to FIGS. 1 to 3, a battery module (100) according to one embodiment of the present invention includes a plurality of battery cells (110), a module case (130), a polymer member (140), and a filler (150).

[0034] Specifically, the battery cell (110) may be a cylindrical battery cell having a cylindrical battery can. The cylindrical battery cell (110) may have electrode terminals (111, 112) located at the top and / or bottom. For example, the cylindrical battery cell (110) may have a positive terminal (111) and a negative terminal (112) at the top. Furthermore, in the case of a cylindrical battery cell, the cap assembly at the top may be the positive terminal (111), and the battery cell body, i.e., the battery can (case), may be the negative terminal (112). Additionally, the positive terminal (111) and the negative terminal (112) may be spaced apart from each other. The positive terminal (111) and the negative terminal (112) may be electrically insulated from each other.

[0035] Additionally, a battery module (100) according to one embodiment of the present invention may further include a busbar (120). The busbar (120) may include a metal material such as aluminum, copper, or nickel. The plurality of battery cells (110) may be electrically connected in series, parallel, or both series and parallel through the busbar (120). Additionally, the busbar (120) may be electrically connected to the positive terminal (111) or negative terminal (112) of the battery cell (110) through a metal wire (121). For example, one end of the metal wire (121) may be configured to contact the positive terminal of the battery cell (110), and the other end may be configured to contact the busbar (120). Alternatively, the busbar (120) may be in direct contact with the electrode terminals (111, 112) without the metal wire (121).

[0036] Since the configuration of such a battery cell (110) is widely known to those skilled in the art at the time of filing the present invention, a more detailed description is omitted in this specification. Additionally, although an example of a battery cell (110) is illustrated in FIG. 3, the battery module (100) according to the present invention is not limited to the configuration of a specific type of battery cell (110). That is, various types of battery cells (110) known at the time of filing the present invention may be employed in the battery module (100) according to the present invention.

[0037] Additionally, the module case (130) may be configured to have an internal space formed therein so that a plurality of battery cells (110) are accommodated in this internal space. For example, the module case (130) may have a box shape with an empty interior to accommodate a plurality of battery cells (110). As a more specific example, the module case (130) may be provided with an upper frame (133) and a lower frame (134). Here, the upper frame (133) may be configured to surround the upper and side portions of the plurality of battery cells (110). And, the lower frame (134) may be provided with a plurality of mounting grooves (H) configured to allow a portion of the plurality of battery cells (110) to be inserted. For example, the mounting grooves (H) of the lower frame (134) may be configured so that the lower portion is inserted relative to the center of the battery cell (110).

[0038] Furthermore, the module case (130) may be provided with a plurality of exposed openings (131) on the upper and / or lower portions. Each of the plurality of exposed openings (131) may be configured in a form in which a part of the module case (130) is perforated so that the upper portions of the plurality of battery cells (110) can be exposed to the outside. For example, as shown in FIG. 2, a plurality of exposed openings (131) may be provided on the upper surface of the upper frame (133) so that electrode terminals (111, 112) provided on the upper portions of the plurality of battery cells (110) can be exposed to the outside.

[0039] The polymer member (140) may be configured to fill at least a portion of the internal space of the module case (130). Furthermore, since a plurality of battery cells (110) are housed in the internal space of the module case (130), the polymer member (140) may be filled in at least a portion of the space other than the space occupied by the battery cells. In particular, as shown in FIG. 3, the polymer member (140) may be provided in one or more of the space between the plurality of battery cells (110) and the space between the plurality of battery cells and the inner surface of the module case (130).

[0040] The above filler material (150) may be located in at least a portion within the polymer member (140). That is, the filler material (150) may be embedded entirely within the polymer member (140) or partially exposed to the outside of the polymer member (140). Additionally, the filler material (150) may be interposed in the space between at least one of the plurality of battery cells and the inner surface of the module case together with the polymer member (140). Furthermore, the filler material (150) may be interposed in the space between the plurality of battery cells (110) together with the polymer member (140).

[0041] According to this aspect of the present invention, the presence of a polymer member (140) and a filler (150) having different physical properties or characteristics within the battery module (100) may be advantageous for ensuring various performance characteristics together. For example, the polymer member (140) may be composed of a material capable of ensuring safety against heat or fire, and the filler (150) may be composed of a material with excellent rigidity or low weight or cost. In this case, a battery module with excellent rigidity, lightness, and economic efficiency, along with safety against heat or fire, can be realized. Furthermore, the polymer member (140) can act as a barrier to prevent flames from being transmitted to adjacent battery cells (110) when one of the plurality of battery cells (110) ignites or explodes. Accordingly, it can effectively prevent the chain explosion of the plurality of battery cells (110) or the spread of fire.

[0042] The above polymer member (140) may be provided with silicone resin. According to this embodiment, it may be advantageous to ensure safety regarding heat or fire, etc., for the battery module (100). For example, if such silicone resin is located between the battery cell (110) and the module case (130), it is possible to prevent heat or fire from the battery cell (110) from spreading to the outside of the module case (130). In addition, in this case, not only is it advantageous to prevent the explosion of the battery cell (110), but even if an explosion occurs, it is possible to suppress as much as possible the scattering of fragments caused by the explosion to the outside of the battery module (100). Furthermore, if silicone resin is located between the battery cells (110), it is possible to prevent heat or fire from spreading to each other between the battery cells (110). Therefore, in this case, it is possible to prevent thermal runaway propagation, etc., from occurring inside the battery module. The silicone polymer resin may be an artificial polymer compound having a main framework formed by siloxane bonds. However, the resin used in the polymer member (140) of the present invention is not specified as any one specific type, and various types of resins known at the time of filing the present invention may be employed as the polymer member (140) of the present invention. For example, the polymer member (140) may be provided with an epoxy resin.

[0043] The polymer member (140) may have a hardened form after being filled into at least a portion of the internal space of the module case (130). In particular, the polymer member (140) may have a hardened form after being injected into the module case (130) in a fluid state, such as a liquid, gel, or sol, while the battery cell (110) is housed inside the module case (130).

[0044] For example, the polymer member (140) may be injected into the internal space of the module case (130) in the form of a liquid silicone resin and introduced into the space between the battery cells (110) and / or the space between the battery cells (110) and the module case (130). The polymer member (140) may be configured in a hardened form after a certain period of time has elapsed or through cooling. Furthermore, the polymer member (140) may have a solid state at room temperature.

[0045] The above filler (150) may have a plurality of particles. The plurality of particles of the filler (150) may be configured to be dispersed within the polymer member (140). In particular, each of the plurality of particles provided in the filler (150) may be configured in the form of a pellet. Such pellets can be manufactured by various methods, such as injection molding or powder compression. In such a configuration, one pellet can be considered as one particle. Therefore, the filler (150) may be said to have a plurality of pellets (151). These plurality of particles, i.e., pellets (151), may be mixed with the polymer member (140) in a fluid state and then injected into the module case (130). Furthermore, as the polymer member (140) in a fluid state hardens inside the module case (130), it may be configured to have a fixed position.

[0046] In particular, a plurality of pellets (151) may be injected into the internal space of the module case (130) while a plurality of battery cells (110) are accommodated therein. At this time, after the plurality of pellets (151) as the filler material (150) are injected into the internal space of the module case (130), a polymer member (140) in a fluid state may be injected into the internal space of the module case (130). Alternatively, the plurality of pellets (151) as the filler material (150) may be pre-mixed with the polymer member (140) in a fluid state to form a mixture, and then the mixture of the pellets (151) and the polymer member (140) may be injected into the internal space of the module case (130).

[0047] The above-mentioned filler particles (150), such as pellets (151), may be configured to be interposed between the module case (130) and the battery cell (110), and / or between a plurality of battery cells (110), during the process in which a polymer member (140) in a fluid state is injected into the internal space of the module case (130). To this end, the above-mentioned filler particles (150), i.e., pellets (151), may have a size or shape that can be inserted into the space between the module case (130) and the battery cell (110), and / or between a plurality of battery cells (110).

[0048] According to this embodiment of the present invention, through a filler material (150) such as pellets (151), characteristics different from those of the polymer member (140) can be easily achieved inside the battery module (100). For example, the filler material (150) may be advantageous for increasing the mechanical strength of the battery module (100). For example, when an external impact is applied to the battery module (100), the strength of the battery module (100) can be improved because a plurality of pellets (151), which have higher mechanical strength than the polymer member (140), are added inside the polymer member (140). Therefore, in this case, a plurality of battery cells (110) can be protected more effectively from external impact. Furthermore, according to this embodiment, the transmission of impact between battery cells (110) can be reduced by the plurality of pellets (151) which are the filler material (150).

[0049] In addition, the above embodiment may be advantageous for lowering the manufacturing cost of the battery module (100). In particular, when silicone resin is used as a polymer material (140) to ensure safety against heat or fire, etc., there may be a disadvantage that the price of silicone resin is high. However, according to the above embodiment, the amount of expensive material such as silicone resin can be reduced, so the manufacturing cost of the battery module (100) can be lowered.

[0050] In addition, the above embodiment configuration may be advantageous for reducing the weight of the battery module (100). For example, if the filler material (150) is composed of a material with a weight less than that of the polymer member (140), the weight of the battery module (100) can be reduced.

[0051] The above filler (150) may be a plastic material. Here, the plastic material used as the filler (150) may be adopted from various materials known at the time of filing the present invention. In particular, the above filler (150) may include polytetrafluoroethylene (PTFE). In the case of such PTFE, it may be more advantageous because it has low surface energy. In addition, polypropylene or polyethylene may also be used as the material for the above filler (150) as they are materials with low surface energy.

[0052] In this way, when using a filler (150) made of plastic with relatively low surface energy (surface tension), the influence of the viscosity of the polymer member (140) can be reduced when mixed with the polymer member (140) in a fluid state. Therefore, the filler (150) can be dispersed more easily within the polymer member (140) in a fluid state. Consequently, in this case, due to the even dispersion of the filler (150) within the polymer member (140), manufacturing efficiency can be increased, and the effect of the filler (150), such as securing mechanical strength, can be more advantageous.

[0053] In addition, the filler (150) may be provided with various other plastic materials, such as polyvinyl chloride, polystyrene, polyethylene terephthalate, etc.

[0054] Furthermore, the plastic material described above may have the advantages of being lightweight, inexpensive, and easy to mold. Therefore, according to this embodiment, it may be advantageous in terms of reducing the weight and cost of the battery module (100). In addition, the plastic material may be advantageous for ensuring thermal insulation. Therefore, heat transfer between the battery cells (110) or between the battery cells (110) and the module case (130) can be blocked more effectively.

[0055] Additionally, the filler material (150) may be a ceramic material. The ceramic material may include one or more of sand, glass, cement, clay, refractory material, abrasive material, and fine ceramic. The sand may include one or more of quartz, limestone, iron ore, magnetite, basalt, obsidian, and olivine.

[0056] In the case of ceramic materials, they may include materials that have properties resistant to heat or flame. In this case, the heat or flame blocking effect by the filler (150) can be further enhanced.

[0057] Additionally, the battery module (100) of the present invention may include a cooling member (160) for cooling a plurality of battery cells (110). As shown in FIG. 2, the cooling member (160) may be located at the bottom of the lower frame (134). For example, the cooling member (160) may be configured such that an external refrigerant is injected into it, and the refrigerant, which has been heated by absorbing heat from the battery cells (110), is discharged outward. As an example, the cooling member (160) may be provided with an aluminum alloy material having excellent thermal conductivity.

[0058] Meanwhile, the particles of the filler material (150), such as pellets (151), can be configured in various forms. For example, as shown in FIG. 3, the pellets (151) can be formed with a spherical shape. According to this embodiment, the shape of the pellets (151) is spherical, so the frictional force with the battery cell (110) can be minimized. In addition, since the pellets (151) have a spherical shape, it can be advantageous to fill the empty space between the multiple battery cells (110) evenly with high density. Furthermore, according to this embodiment of the present invention, when an external impact is applied to the battery module (100) and the pellets (151) collide with the battery cell (110), damage to the battery cell (110) caused by the collision can be minimized.

[0059] FIG. 4 is a diagram schematically illustrating the internal configuration of a battery module according to another embodiment of the present invention. For the present embodiment and other embodiments below, detailed descriptions are omitted for parts where the content described in the preceding embodiments can be applied identically or similarly, and descriptions focus on the parts where there are differences.

[0060] Referring to FIG. 4, the particles of the filler (150) may be composed of powder. In this case, the filler (150) may be said to have a plurality of powder particles (152). While the pellet (151) in the previous embodiment is said to be processed or molded into a specific shape with respect to a plastic material or ceramic material, the powder particles (152) in this embodiment may be said to be in a crushed form with respect to a plastic material or ceramic material. Here, the powder particles (152) may have a smaller size than the pellet (151). For example, the size (average particle size) of the powder particles (152) may be 1 µm to 1 mm.

[0061] These multiple powder particles (152) can be injected into the module case (130) while mixed with the polymer member (140) in a fluid state. Then, when the polymer member (140) hardens, the multiple powder particles (152) can be dispersed and positioned within the polymer member (140).

[0062] According to this embodiment of the present invention, the injection process of the polymer member (140) and / or filler (150) can be performed more easily. That is, when a mixture of a polymer member (140) in fluid form and a plurality of powder-type particles (152) is injected into the module case (130), the viscosity of the mixture to be injected can be easily controlled by the particle size of the powder-type particles (152). Accordingly, the efficiency of the injection process can be further improved, such as by allowing an operator to appropriately control the viscosity of the mixture to shorten the time required to inject it into the module case (130).

[0063] FIG. 5 is a diagram schematically showing a part of the internal configuration of a battery module according to another embodiment of the present invention.

[0064] Referring to FIG. 5, the filler (150) may comprise a plurality of particles having different sizes. For example, as shown in FIG. 5, when a plurality of pellets (151) are included inside a polymer member (140) as filler particles, some of the pellets (151) may have a relatively large size (particle diameter) and other parts may have a relatively small size (particle diameter). As a more specific example, some pellets (151) may have a particle diameter of approximately 1 mm, and other pellets (151) may have a size of approximately 0.5 mm.

[0065] In this embodiment, a plurality of particles of different sizes, i.e., pellets (151), may be located in the space between different battery cells (110). For example, among the plurality of pellets (151), the pellet (151) having a relatively smaller size may be located in the narrow space between the battery cells (110), as indicated by G1 in FIG. 5. On the other hand, the pellet (151) having a relatively larger size may be located in the space between the different battery cells (110) that is relatively wider, as indicated by G2 in FIG. 5, or in the space between the battery cells (110) and the inner surface of the module case (130).

[0066] Accordingly, according to this embodiment of the present invention, by providing a plurality of particles of different sizes as the filler (150), more filler (150) can be introduced into spaces of various sizes. In particular, spaces of various sizes may exist within the internal space of the module case (130). At this time, by introducing small-sized particles into narrow spaces, the polymer member (140) and the filler (150) can exist in an appropriate ratio so that their respective functions are sufficiently achieved. In addition, by introducing large-sized particles into wide spaces, the amount of polymer member (140) introduced can be reduced, and the viscosity of the polymer member (140) caused by the filler (150) can be prevented from becoming excessively high.

[0067] In addition, in this case, particles such as pellets (151) can be evenly dispersed within the polymer member (140) without being concentrated in one place. That is, according to this embodiment of the present invention, when a plurality of particles having at least two or more sizes are provided as the filler (150), it may be advantageous for the plurality of particles to exist in a state where they are evenly spread within the polymer member (140) without being concentrated in a specific part. Therefore, the effect of securing mechanical strength by a mixture of the polymer member (140) and a plurality of particles, such as a plurality of pellets (151), can be further enhanced. Therefore, when an external impact occurs to the battery module (100), the external impact protection effect on the battery cell (110) can be further improved due to the enhanced mechanical strength.

[0068] Additionally, the filler (150) may comprise a plurality of particles having different weights (densities). That is, the filler (150) may comprise a plurality of particle groups having different weights. For example, the filler (150) may comprise a plurality of particles having three different weights. At this time, the plurality of particles may be divided into three particle groups according to weight, which may be called the first particle group, the second particle group, and the third particle group, respectively. Here, the particles belonging to the first particle group have the largest weight, and the particles belonging to the second particle group may have a lower weight than the particles in the first particle group. And, the particles belonging to the third particle group may have a lower weight than the particles in the second particle group.

[0069] In this way, when a plurality of particles having different weights are included as the filler material (150), it may be advantageous for the filler material (150) to be more evenly dispersed inside the module case (130). For example, as in the above embodiment, when three groups of particles with different weights are included, after these particles are mixed in the polymer member (140) in a fluid state and injected into the module case (130), the three groups of particles can be dispersed in the up-and-down direction according to weight. That is, while the polymer member (140) in a fluid state has fluidity before hardening, a plurality of particles can be dispersed in the up-and-down direction inside the module case (130) according to weight. That is, the first group of particles with the heaviest weight can be located around the bottom part of the battery cell (110), and the third group of particles with the lightest weight can be located around the top part of the battery cell (110). And, the second group of particles with an intermediate weight can be located around the center part of the battery cell (110).

[0070] Meanwhile, this difference in weight may manifest as a difference in specific gravity or density. For example, the first particle group may be composed of a material with a higher specific gravity than the polymer member (140) in a fluid state. And, the third particle group may be composed of a material with a lower specific gravity than the polymer member (140) in a fluid state. Additionally, the second particle group may be composed of a material with a specific gravity similar to that of the polymer member (140) in a fluid state.

[0071] Additionally, the filler (150) may comprise a plurality of particles having different shapes (outer forms). For example, the filler (150) may include at least two of the following: square column-shaped particles, triangular column-shaped particles, spherical particles, and particles having at least one surface formed in a curved shape.

[0072] Since various shaped spaces may exist within the internal space of the module case (130), according to the above embodiment, particles having a shape suitable for the shape of each space can be introduced. Therefore, in this case, it may be advantageous for the even dispersion of particles within the module case (130).

[0073] FIG. 6 is a cross-sectional view schematically showing the particle composition of a filler included in a battery module according to another embodiment of the present invention.

[0074] Referring to FIG. 6, the particles included in the filler material (150), such as pellets (151), may have an empty space (S) formed inside. For example, the pellets (151) may have an outer wall (W) surrounding the empty space (S). And, the empty space (S) of the pellets (151) may be filled with air. At this time, when the pellets (151) are pressurized by swelling or movement of the battery cell (110), they can elastically support the battery cell (110). Furthermore, the pellets (151) may be configured such that their volume decreases or their external shape changes when compressed by the plurality of battery cells (110).

[0075] Accordingly, according to this embodiment of the present invention, through particles configured to have an empty space (S) containing only a gas such as air inside, the battery module (100) can cushion the pressure or shock applied to the battery cell (110) due to external collision or swelling of the battery cell (110).

[0076] In particular, when the outer wall (W) of a particle such as a pellet (151) is made of an elastic plastic material, the cushioning effect of the pellet (151) can be more easily secured.

[0077] FIG. 7 is a cross-sectional view schematically showing the particle composition of a filler included in a battery module according to another embodiment of the present invention.

[0078] Referring to FIG. 7, the pellet (151) as the filler (150) may be configured in a form containing a extinguishing substance inside. In particular, the filler (150) may have a plurality of pellets (151) containing a extinguishing substance. Here, the pellet (151) may have a receiving space formed therein, and a extinguishing substance (151a) may be provided in such a receiving space. In particular, the pellet (151) may be configured in the form of a capsule filled with a extinguishing substance (151a) inside. Here, the extinguishing substance (151a) may be, for example, a concentrated solution of an inorganic salt such as potassium carbonate, chemical foam, air foam, carbon dioxide, or water. In addition, various extinguishing agents in solid, liquid, or gaseous states known at the time of filing the present invention may be employed as the extinguishing substance contained in the particles of the filler (150), such as the pellet (151). In such an embodiment, the pellet (151) may be configured to melt at a predetermined temperature. For example, the pellet (151) may be configured to melt at 300 degrees Celsius or higher to discharge the extinguishing material (151a) contained in the internal receiving space to the outside.

[0079] Accordingly, according to this configuration of the present invention, the safety of the battery module (100) can be further enhanced by the pellet (151) containing the fire extinguishing substance (151a). For example, if a fire and explosion occur in some of the plurality of battery cells (110) contained in the battery module (100), the outer wall of the pellet (151) melts, and the fire extinguishing substance (151a) contained inside is discharged to the outside, thereby suppressing the fire of the battery cells (110) at an early stage and effectively blocking its spread. Accordingly, the present invention can significantly increase fire safety.

[0080] FIG. 8 is a cross-sectional view schematically showing the particle composition of a filler included in a battery module according to another embodiment of the present invention.

[0081] Referring to FIG. 8, the pellet (151) included in the filler (150) may be configured in a form containing a flame-retardant liquid. In particular, the filler (150) may have a plurality of pellets (151) containing a flame-retardant liquid. In this case, the pellet (151) may have a receiving space formed inside, and a flame-retardant liquid (151b) may be provided in such a receiving space. Furthermore, the pellet (151) may be configured in a capsule form containing the flame-retardant liquid (151b). Here, the flame-retardant liquid (151b) may be, for example, a polymer resin mixed with a flame-retardant additive. Such flame-retardant additive may be alumina trihydrate, a bromine-based flame retardant, antimony trioxide, a phosphorus-based flame retardant, etc. In addition, the polymer resin may be acrylonitrile butadiene styrene (ABS) resin, polypropylene (PP) resin, polyamide (PA) resin, or polycarbonate resin, etc.

[0082] According to this embodiment of the present invention, the safety of the battery module (100) can be improved through the pellet (151) containing the flame-retardant liquid (151b). For example, if a fire and explosion occur in some of the plurality of battery cells (110), the outer wall of the pellet (151) melts, and the flame-retardant liquid (151b) contained inside can be discharged to the outside. Therefore, in this case, the flame-retardant liquid (151b) can be supplied to the inside or outside of the battery cell (110) where the fire occurred, or the ruptured part of the battery can can be sealed. In this respect, fire safety can be greatly improved.

[0083] FIG. 9 is a cross-sectional view schematically showing the particle composition of a filler included in a battery module according to another embodiment of the present invention.

[0084] Referring to FIG. 9, a plurality of pellets (151) included in the filler (150) may be configured to have a portion of the polymer member (140) inserted therein. To this end, the pellets (151), which are particles of the filler (150), may have at least one passage (151c) formed therein. Here, the passage (151c) may be configured to penetrate from one end of the pellet (151) to the other end, as shown in FIG. 9. Alternatively, the passage (151c) may be configured to be carved from one end of the pellet (151) to a predetermined point in the center. According to this embodiment, the polymer member (140) can penetrate into the interior of the passage (151c) when it is fluid. And, subsequently, when the polymer member (140) hardens, a portion of the polymer member (140) can be configured to be inserted into the flow channel (151c) of the pellet (151).

[0085] According to this embodiment of the present invention, it may be more advantageous for the even dispersion of the pellet (151), which is the filler material (150). In particular, when the flow channel (151c) is formed in a shape that completely penetrates the interior of the pellet (151), the difference in specific gravity (weight) between the pellet (151) and the polymer member (140) can be mitigated. For example, even if the pellet (151) is made of a material with a lower specific gravity than the polymer member (140), the polymer member (140) flows into the interior of the flow channel (151c), so that the pellet (151) does not float only to the top but moves downward within the polymer member (140) in a fluid state. Therefore, in this case, the pellet (151) can be made to exist not only at the top but also at the bottom of the module case (130).

[0086] In addition, according to the above embodiment, a polymer member (140) may be present inside the pellet (151) which is the filler (150). Therefore, even if there is a part where the pellet (151) is clumped together, the characteristics of the polymer member (140) can be expressed to a certain level or higher.

[0087] FIG. 10 is a diagram schematically showing the particle composition of a filler included in a battery module according to another embodiment of the present invention.

[0088] Referring to FIG. 10, each pellet (151) included in the filler (150) may be configured in a form in which a plurality of powders (151d) are compressed and mechanically bonded together. Alternatively, a binder or the like may be additionally provided between the plurality of powders (151d) that are compressed together. Here, the powder (151d) may be a powder made of plastic material or a powder made of ceramic material. In this embodiment, the pellet (151) may be configured to decompose upon external impact. That is, since the pellet (151) is in a state in which a plurality of powders are mechanically bonded, it may have a bonding force that allows it to decompose (separate) into powder or various fragments when a large impact is applied to the battery module.

[0089] According to this embodiment of the present invention, shock can be mitigated during the process in which the pellet (151) is broken down into a form such as powder. In addition, damage to the battery cell (110) by powder or fragments generated from the breakdown of the pellet can be prevented.

[0090] FIG. 11 is a cross-sectional view schematically showing the particle composition of a filler included in a battery module according to another embodiment of the present invention.

[0091] Referring to FIG. 11, a plurality of particles, such as pellets (151), included as the filler (150) may have an outer layer (151e) and an inner layer (151f). Here, the inner layer (151f) may be configured in a porous form. Here, air may be filled in the inner layer (151f). And, the outer layer (151e) may be configured in a sealed form so that the porous inner layer (151f) is accommodated inside. That is, the pellets (151) may have an outer layer (151e) in a sealed form so that external substances do not penetrate into the interior.

[0092] For example, the inner layer (151f) of the pellet (151) may be formed in a porous form by a foaming resin. For example, the foaming resin forming the inner layer (151f) may be expandable polystyrene resin. And, the outer layer (151e) of the pellet (151) may be formed by coating the outside of the porous inner layer with a polymer resin. For example, the polymer resin forming the outer layer (151e) may be polyvinyl chloride.

[0093] According to this embodiment of the present invention, a shock-absorbing effect can be secured by the porous inner layer (151f) provided in the pellet (151). Furthermore, in the above embodiment, the outer layer (151e) is configured in a sealed form so that the polymer material (140) in a fluid state can be prevented from penetrating into the porous inner layer (151f). Therefore, in this case, the amount of polymer material (140) used can be further reduced. In addition, in this case, it may be more advantageous to reduce the weight of the filler (150).

[0094] Additionally, the filler (150) may comprise a plurality of particles configured in different shapes. In particular, various types of particles described in the preceding embodiments may be provided together as the filler (150) of the present invention.

[0095] For example, the filler (150) may have a group of pellets (151) configured in the shape shown in FIG. 6 and a group of pellets (151) configured in the shape shown in FIG. 7. Alternatively, the filler (150) may have a group of pellets (151) configured in the shape shown in FIG. 8 and a group of pellets (151) configured in the shape shown in FIG. 9. Alternatively, the filler (150) may be configured to include three or more types of pellets (151) among the pellets (151) configured in the shapes shown in FIG. 6 to FIG. 11.

[0096] According to this embodiment of the present invention, particles constituting the filler (150) can be more uniformly dispersed within the internal space of the module case (130). For example, when the pellet (151) of FIG. 6 containing air and the pellet (151) of FIG. 7 containing a fire extinguishing substance (151a) are included together as filler (150), the pellet (151) of FIG. 6 may be lighter than the pellet (151) of FIG. 7. Accordingly, the pellet (151) of FIG. 6 may be located at the top of the internal space of the module case (130), and the pellet (151) of FIG. 7 may be located at the bottom of the internal space of the module case (130).

[0097] As another example, when the pellet (151) of FIG. 8 containing a flame-retardant liquid (151b) inside and the pellet (151) of FIG. 9 having a flow channel (151c) formed together are included as a filler (150), the pellet (151) of FIG. 9 may be placed below the pellet (151) of FIG. 8.

[0098] As another example, when the pellet (151) of FIG. 10 and the pellet (151) of FIG. 11 are included together as a filler (150), the pellet (151) of FIG. 11 may be placed above the pellet (151) of FIG. 10 due to the porous inner layer (151f).

[0099] Therefore, according to such embodiments, the filler material (150) can be smoothly distributed in the vertical direction within the internal space of the module case (130).

[0100] In addition, according to the above embodiment of the present invention, various characteristics can be included in the filler (150) by means of various types of pellets (151). In particular, the various characteristics of each pellet (151) can be placed in the part where the corresponding characteristic is required.

[0101] For example, the pellet (151) of FIG. 7 or FIG. 8 may be placed in the portion (upper part in FIG. 3) where the positive terminal (111) of the battery cell (110) is located. In this case, if high-temperature gas or fire is discharged toward the positive terminal, the fire extinguishing material (151a) or flame-retardant liquid (151b) contained inside the pellet (151) can be quickly discharged. Therefore, it may be advantageous for suppressing ignition or fire, or preventing its spread.

[0102] In addition, as another pellet (151) in addition to this pellet (151), the pellet (151) of FIG. 6, FIG. 10, or FIG. 11 may be located in the central part of the body of the battery cell (110) (the central part in the Z-axis direction in FIG. 3). In this case, when swelling of the battery cell (110) or external impact occurs, the impact transmitted between the battery cells (110) or from the module case (130) to the battery cell (110) can be mitigated.

[0103] Therefore, according to this embodiment of the present invention, various pellets (151) configured in an appropriate shape according to the characteristics of each part of the battery module (100) are included as a filler (150), and the effects according to the present invention, such as the safety of the battery module (100), can be further improved.

[0104] Meanwhile, the battery pack according to the present invention may include one or more battery modules (100) according to the present invention as described above. In addition, the battery pack according to the present invention may include various components typically provided in a battery pack in addition to the battery modules (100), such as a battery management system (BMS) electrically connected to the battery modules (100). In particular, the BMS may be equipped with various circuits or components to control the charging and discharging of a plurality of battery cells (110) included in the battery modules (100).

[0105] Meanwhile, the vehicle according to the present invention may include one or more battery modules (100) according to the present invention as described above. In particular, the vehicle may be a vehicle driven by electricity, such as an electric vehicle, an electric scooter, an electric wheelchair, or an electric bike. In addition, the vehicle according to the present invention may further include various other components included in the vehicle in addition to the battery module (100), such as a vehicle body, a motor, an inverter, etc.

[0107] As described above, although the present invention has been explained by limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs. Explanation of the symbols

[0108] 100: Battery module 110: Battery cell, 111: Electrode terminal 120: Busbar, 121: Metal wire 130: Modular case, 131: Exposure opening, 133: Upper frame, 134: Lower frame, H: Seating groove 140: Polymer component 150: Filler 151: Pellet, 152: Powdered particles S: Empty space, 151a: Fire extinguishing substance, 151b: Flame-retardant liquid, 151c: Flow port 151d: Powder, 151e: Outer layer, 151f: Inner layer 160: Cooling element

Claims

Claim 1 A battery module comprising: a plurality of battery cells; a polymer member disposed between the plurality of battery cells; and a filler disposed inside the polymer member and having an empty space inside. Claim 2 A battery module according to claim 1, further comprising a case accommodating the plurality of battery cells, the polymer member, and the filler. Claim 3 In claim 1, the polymer member is a battery module comprising a resin. Claim 4 In claim 1, the polymer member is a battery module having a cured form. Claim 5 In claim 1, the battery module is provided in a plurality of fillers and dispersed within the polymer member. Claim 6 In claim 1, the filler is a battery module comprising a plastic material. Claim 7 In claim 1, the filler material is a battery module having a spherical shape. Claim 8 A battery module according to claim 1, wherein the diameter of the filler is 1 µm to 1 mm. Claim 9 In claim 1, the filler is a battery module comprising a material having elasticity. Claim 10 A battery pack comprising a battery module according to any one of claims 1 to 9. Claim 11 An automobile comprising a battery module according to any one of claims 1 to 9.

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