Patent Description:
Recently, secondary batteries are widely used not only in small devices such as portable electronic devices but also in middle-sized or large-sized devices such as electric vehicles and energy storage devices (ESS). When used in the electric vehicle, for example, a large number of secondary batteries are electrically connected to form a battery module, and a plurality of battery modules are connected to configure a battery pack, in order to increase energy capacity and output. An example of battery module is disclosed in <CIT>.

The housing of various electric components inside the battery module/pack mainly uses injection molding. The injection-molded product is made of plastic, and resin serving as a material for injection molding is melted under high heat and then put into a mold to complete the product. <CIT> discloses a method for manufacturing molded article.

The injection molding process essentially has a disadvantage of causing deformation of the product during the cooling process after injection as the high-temperature resin contacts an external ambient temperature. This deformation deteriorates dimensional reliability of the product and weakens mechanical strength of the injection-molded product. Therefore, there is a need to reduce the deformation amount during the cooling process and to secure the strength and reliability of the electric component housing after injection.

Meanwhile, the battery module may include various electric components for controlling charging and discharging of battery cells, such as a BMS, a relay, a current sensor, and a fuse. The electric component housing integrally houses the various electric components. However, in line with the trend of miniaturization of the battery module/pack, the size of the electric component housing is also being reduced. Therefore, there is a need to increase the space utilization of the electric component housing by minimizing the space occupied by cables or bus bars in the electric component housing.

The present disclosure is directed to providing a system comprising an electric component housing with high mechanical rigidity and deformation prevention after injection molding.

The present disclosure is also directed to providing an electric component housing with space freedom and convenient electric component packaging by integrating bus bars or the like to the housing.

Other objects and advantages of the present disclosure will be described below, and will be appreciated by embodiments of the present disclosure. In addition, the objects and advantages of the present disclosure can be realized by components defined in the claims and a combination thereof.

In one aspect of the present disclosure, there is provided a system according to claim <NUM>.

The housing body may be made of a plastic material, and the housing body may be prepared by insert injection molding together with the metal support structure.

The metal support structure may be embedded inside at least one of the bottom portion and the wall portion.

The metal support structure may include at least one bus bar, the bus bar may include terminal portions having a fastening hole and corresponding to both end portions and a connection portion configured to form a current path between the terminal portions, the terminal portions of the bus bar may be exposed to an inner space of the housing body, and the connection portion of the bus bar may be embedded inside at least one of the bottom portion and the wall portion.

The electric component housing may further comprise a terminal support provided to a corner area of the bottom portion and having a box shape, one of the terminal portions of the bus bar may be disposed at an upper surface of the terminal support, and the other of the terminal portions of the bus bar may be disposed to stand upright from the bottom portion.

The housing body may have a plurality of heat dissipation holes formed by cutting a part of the bottom portion so that at least a part of the connection portion of the bus bar is exposed out of the housing body.

The metal support structure may include at least one horizontal frame configured to extend in a horizontal direction of the bottom portion and at least one vertical frame configured to extend in a vertical direction of the bottom portion.

The housing body may further include a flange portion configured to protrude out of the wall portion from the bottom portion, and the vertical frame may have a bushing hole formed at an end thereof so that a bolt passes therethrough, and the bushing hole is located inside the flange portion.

In another aspect of the present disclosure, there is also provided a battery module, comprising the electric component housing described above.

In still another aspect of the present disclosure, there is also provided a method of manufacturing a system system as defined in any one of claim <NUM> to <NUM> comprising an electric component housing of a battery module, which accommodates electric components, the method comprising: a housing injection molding step of performing insert injection molding such that a metal support structure is embedded in a housing body.

The metal support structure may include at least one bus bar, the bus bar may include terminal portions having a fastening hole and corresponding to both end portions and a connection portion configured to form a current path between the terminal portions, the terminal portions of the bus bar may be exposed to an inner space of the housing body, and the connection portion of the bus bar may be embedded inside at least one of a bottom portion and a wall portion of the housing body.

According to an embodiment of the present disclosure, since the metal support structure may act as a skeleton of the housing body, it is possible to provide an electric component housing having high mechanical rigidity and deformation prevention after injection molding.

According to another embodiment of the present disclosure, since the bus bar or the like are manufactured in an integrated structure with the housing body, it is possible to provide an electric component housing that is convenient for electric component packaging.

In addition, in the electric component housing according to the present disclosure, since only the terminal portion of the bus bar is exposed out of the housing body and the remaining portion of the bus bar plays a role of the metal support structure, there is no need to coat the bus bar for insulation.

The effects of the present disclosure are not limited to the above, and effects not mentioned herein may be clearly understood from the present specification and the accompanying drawings by those skilled in the art.

The embodiments disclosed herein are provided for more perfect explanation of the present disclosure, and thus the shape, size and the like of components may be exaggerated, omitted or simplified in the drawings for better understanding. Thus, the size and ratio of components in the drawings do not wholly reflect the actual size and ratio.

An electric component housing, which will be described below, is used to accommodate and protect various electric components inside a battery module or a battery pack. That is, the electric component housing mentioned in this embodiment may be included as a component of a battery module or a battery pack. Of course, the electric component housing according to the present disclosure does not necessarily have to be used only as a component of a battery module or battery pack. For example, the electric component housing may be applied as an electric component housing for an energy storage system and other electric devices.

<FIG> is a schematic perspective view showing an electric component housing according to an embodiment of the present disclosure, and <FIG> is a diagram showing a state where electric components are accommodated in the electric component housing of <FIG>.

Referring to these drawings, an electric component housing <NUM> according to an embodiment of the present disclosure includes a housing body <NUM> forming an appearance, and a metal support structure <NUM> embedded in the housing body <NUM>.

The housing body <NUM> includes a bottom portion <NUM> and a wall portion <NUM>.

The bottom portion <NUM> is a portion that forms a bottom surface of the housing body <NUM> and may be provided in a substantially rectangular plate shape with a predetermined thickness. Electric components are fixedly installed at a predetermined position on the bottom portion <NUM>. The electric components are, a main relay 20a, a current sensor 20b, a precharge relay 20c, a register 20d, and their combinations.

The wall portion <NUM> is a portion that forms walls along a peripheral edge of the bottom portion <NUM> and may be integrally formed with the bottom portion <NUM>. The electric components are arranged in the space of the bottom portion <NUM> surrounded by the wall portion <NUM>. The housing body <NUM> may be fixedly installed at one side inside a battery module or a battery pack in a state where the space is shielded by a cover or is opened.

The metal support structure <NUM> is a component that acts as the skeleton of the housing body <NUM> inside the housing body <NUM>. For example, the housing body <NUM> may be manufactured by insert injection molding in which the metal support structure <NUM> is put into an injection mold and resin serving as a raw material for injection is injected thereto. As will be described later, the metal support structure <NUM> may be embedded in at least one of the bottom portion <NUM> and the wall portion <NUM> of the housing body <NUM>, and there is no particular limitation as long as it is a metal with mechanical rigidity such as stainless steel, copper, and aluminum alloy.

The metal support structure <NUM> has a relatively smaller thermal deformation coefficient than an injection-molded plastic product. In other words, since the metal support structure <NUM> has much better thermal durability than plastic, deformation hardly occurs even after injection. Since the metal support structure <NUM> is integrated into the injection-molded product, the amount of shrinkage of the injection-molded product may be reduced immediately after injection.

Therefore, the electric component housing <NUM> according to the present disclosure including the metal support structure <NUM> has an advantage of better dimensional accuracy and higher mechanical strength in comparison to a general injection-molded plastic product.

Meanwhile, the metal support structure <NUM> according to this embodiment may include at least one bus bar <NUM>, a horizontal frame <NUM>, and a vertical frame <NUM>.

The bus bar <NUM> is a metal plate with certain thickness, width and length, and is a member that forms a large current path of the battery module/pack. The bus bar <NUM> may be provided to form various paths by bending or twisting to connect specific devices or terminals.

In the present disclosure, the bus bar <NUM> is used as one of the metal support structures <NUM>. In other words, in the present disclosure, a significant part of the bus bar <NUM> is embedded into the electric component housing <NUM> and thus is utilized to reinforce the mechanical strength, and the insulation and space freedom in the electric component housing <NUM> may be improved.

The bus bar <NUM> includes both terminal portions <NUM>, <NUM> and a connection portion <NUM> defining a current path between the both terminal portions <NUM>, <NUM>. The terminal portions <NUM>, <NUM> have fastening holes and are bolted to terminals of external devices or electric components to make electrical connection and mechanical fixation. The connection portion <NUM> may extend as a predetermined path between both terminal portions <NUM>, <NUM> to form various current paths.

Specifically, referring to <FIG> together, the bus bar <NUM> may be used as a part of the metal support structure <NUM> in the form that the terminal portions of the bus bar <NUM> are exposed to the inner space of the bottom portion <NUM> and the connection portion <NUM> of the bus bar <NUM> is embedded in at least one of the bottom portion <NUM> and the wall portion <NUM>.

A box-shaped terminal support <NUM> may be further provided at a corner area of the bottom portion <NUM>. The terminal support <NUM> is a structure that supports the terminal portion <NUM> of the bus bar <NUM> at a certain height from the bottom portion <NUM> and provides a place for embedding a part of the connection portion <NUM> therein.

One terminal portion <NUM> of the bus bar <NUM> may be placed horizontally on the upper surface of the terminal support <NUM>, and the other terminal portion <NUM> may be disposed to stand upright from the bottom portion <NUM> at a position spaced apart from the one terminal portion <NUM> by a predetermined distance. Hereinafter, one terminal portion will be referred to as a first terminal portion <NUM> and the other terminal portion will be referred to as a second terminal portion <NUM>.

Although not shown for convenience of drawing, the first terminal portion <NUM> may contact one end of another bus bar or one end of a cable connected to one of electrode terminals of a cell assembly, and may be fixed by being fastened with a bolt. At this time, an outer portion of the corner area of the housing body <NUM> where the terminal support <NUM> is provided may have a concave shape so that the bolt may pass through the terminal support <NUM> and be easily fastened to the fastening hole of the first terminal portion <NUM>.

In addition, the second terminal portion <NUM> may contact one of electrode terminals of the main relay 20a located in the space inside the bottom portion <NUM>. The electrode terminal of the main relay 20a may include a bolt that may be inserted into the fastening hole of the second terminal portion <NUM> and a metal plate corresponding to the second terminal portion <NUM>.

The connection portion <NUM> is bent at least once and may extend from the first terminal portion <NUM> to the second terminal portion <NUM> through the inside of the terminal support <NUM> and the inside of the bottom portion <NUM>.

In the conventional bus bar <NUM>, the connection portion <NUM> is generally coated with an insulating tube for insulation and is disposed inside the electric component housing <NUM> to be exposed to the outside. However, in the present disclosure, the connection portion <NUM> is embedded in the housing body <NUM> to serve as a part of the metal support structure <NUM>, so it is possible to exclude coatings such as insulating tubes. In particular, the rigid bus bar with a complicated path is difficult to be coat by inserting into an insulating tube or the like, and the insulating tube itself is also expensive. In this respect, the present disclosure is advantageous not only in enhancing the mechanical strength of the electric component housing <NUM>, but also in manufacturing the bus bar <NUM> and reducing cost.

In this embodiment, one of the two bus bars <NUM> is used to form a current path between a positive electrode terminal of the cell assembly and a positive electrode terminal of the relay device, and the other bus bar <NUM> is used to form a current path between a negative electrode terminal of the cell assembly and a negative electrode terminal of the relay device. Although not shown, in addition to the relay device, an additional bus bar <NUM> may be further embedded in the electric component housing <NUM> in a similar manner for electrical connection of a current sensor, a precharge relay or the like.

If the intensity of the current flowing through the bus bar <NUM> is very large, heat may be generated, so the bus bar <NUM> for high voltage/high current needs to be cooled to maintain the temperature properly.

To this end, the housing body <NUM> according to this embodiment may further include a plurality of heat dissipation holes <NUM> formed by cutting a part of the bottom portion <NUM> so that at least a part of the connection portion <NUM> of the bus bar <NUM> is exposed out of the housing body <NUM>.

That is, as shown in <FIG>, the heat dissipation holes <NUM> are provided at a rear surface of the bottom portion <NUM> in which the connection portion <NUM> of the bus bar <NUM> is embedded, among the bottom portion <NUM> of the housing body <NUM>. The heat dissipation holes <NUM> may be formed, for example, in a grating structure. Therefore, according to this embodiment, the heat generated from the bus bar <NUM> may be dissipated toward the bottom of the housing body <NUM> through the heat dissipation holes <NUM>. In order to more actively cool the bus bar <NUM>, a small fan may be mounted under the heat dissipation holes <NUM> to air-cool the bus bar <NUM>.

Meanwhile, the metal support structure <NUM> according to an embodiment of the present disclosure further includes a plurality of horizontal frames <NUM> and vertical frames <NUM>. It may be desirable to evenly arrange the horizontal frames <NUM> and the vertical frames <NUM> within the area range of the bottom portion <NUM> so as to reduce the deformation of the bottom portion <NUM> as much as possible. To this end, referring to <FIG> and <FIG> together, the horizontal frames <NUM> are elongated along a horizontal direction (X-axis direction) of the bottom portion <NUM> and are disposed to be spaced apart from each other by a predetermined distance, and the vertical frames <NUM> may also be elongated along a vertical direction (Y-axis direction) of the bottom portion <NUM> and are disposed to be spaced apart from each other by a predetermined distance.

The assembly tolerance is generated larger when the bottom portion <NUM> forming the bottom surface of the electric component housing <NUM> is contracted and twisted, rather than when the wall portion <NUM> of the electric component housing <NUM> is contracted and twisted, so this embodiment focuses on preventing the deformation of the bottom portion <NUM> by embedding the metal support structure <NUM> in the bottom portion <NUM>. However, unlike in this embodiment, it is also possible to further embed the horizontal frame <NUM> or the vertical frame <NUM> in the wall portion <NUM> additionally as desired.

The housing body <NUM> may further include a flange portion <NUM> configured to protrude out of the wall portion <NUM> from the bottom portion <NUM>. The flange portion <NUM> may be used as a bolt fastening place when fixing the electric component housing <NUM> to, for example, a tray of the battery module or the battery pack.

Four flange portions <NUM> may be provided in total by providing two flange portions to each of both sides of the housing body <NUM> in the vertical direction (Y-axis direction). In addition, both ends of the vertical frame <NUM> may be located inside the flange portion <NUM>. A bushing hole <NUM> through which a bolt may pass may be provided at the end of the vertical frame <NUM>. In other words, the bushing hole <NUM> may be in a metal tube shape that is formed at the end of the vertical frame <NUM>.

In the present disclosure, since the bushing hole <NUM> of the vertical frame <NUM> is located inside the flange portion <NUM>, it is possible to prevent deformation of the housing body <NUM> after injection and reinforce the mechanical strength of the flange portion <NUM>. Therefore, even if the flange portion <NUM> is strongly coupled to another structure using bolts in the future, the flange portion <NUM> may not be easily broken or damaged. This may be an advantage in stably installing the electric component housing <NUM> to the tray of the battery module or the battery pack.

Next, a method of manufacturing the electric component housing <NUM> according to the present disclosure will be briefly described as follows.

The method of manufacturing the electric component housing <NUM> includes a housing injection molding step of performing insert injection molding to make the housing body <NUM> such that the metal support structure <NUM> is embedded therein.

First, a step of designing the housing body <NUM> including the bottom portion <NUM> and the wall portion <NUM> according to various conditions such as the number and shape of electric components to be mounted and the path of the bus bar <NUM> for connect the electric components, and a step of preparing the metal support structure <NUM> to be embedded in the housing body <NUM> are performed.

Next, a housing injection molding step of performing insert injection molding such that the metal support structure <NUM> is embedded in housing body <NUM> is performed.

The housing injection molding step may be carried out by firstly putting the metal support structure <NUM> into an injection mold and injecting a plastic resin into the injection mold. At this time, the plastic resin may be any resin as long as it has certain durability and electrical insulation.

As described above, the metal support structure <NUM> may employ all of the bus bar <NUM>, the horizontal frame <NUM>, and the vertical frame <NUM>.

In the case of the bus bar <NUM>, the connection portion <NUM> is entirely embedded inside at least one of the bottom portion <NUM> and the wall portion <NUM>, except for the terminal portion of the bus bar <NUM>. Also, all of the horizontal frame <NUM> and the vertical frame <NUM> are elongated along the horizontal and vertical directions of the bottom portion <NUM> and are embedded to be evenly distributed over the area of the bottom portion <NUM>.

Next, the housing body <NUM> is cooled and solidified while maintaining the pressure in the injection mold. At this time, as described above, since the metal support structure <NUM> is evenly embedded in the housing body <NUM>, the change in dimensions of the injection-molded product may be minimized. Subsequently, the electric component housing <NUM> hardened inside the injection mold is taken out, thereby completing the manufacturing process.

As described above, in the electric component housing <NUM> according to the present disclosure, since the metal support structure <NUM> is included in the housing body <NUM>, the dimensional accuracy and mechanical strength of the housing body <NUM> may be improved after injection molding.

In addition, since the bus bar <NUM> is included in an integral structure with the housing body <NUM> as a part of the metal support structure <NUM>, there is no need to separately coat the bus bar <NUM> with an insulating tube or the like and the space freedom is increased, so the electric components may be packaged very efficiently. By using the electric component housing <NUM>, it may be very advantageous to simplify the overall assembly process of the battery module or the battery pack.

Meanwhile, the battery module according to the present disclosure may be configured to include the electric component housing described above, and the battery pack may be configured to include at least one battery module.

The battery pack may be applied to vehicles such as an electric vehicle or a hybrid electric vehicle. Also, the battery pack may be applied to energy storage systems or other IT products.

Claim 1:
A system comprising an electric component housing (<NUM>) of a battery module and electric components,
wherein,
the electric components are accommodated in the electric component housing (<NUM>) , and
the electric component housing (<NUM>) comprising:
a housing body (<NUM>) forming an appearance of the electric component housing (<NUM>); and
a metal support structure (<NUM>) embedded inside the housing body (<NUM>),
wherein the housing body (<NUM>) includes a bottom portion (<NUM>) and a wall portion (<NUM>),
wherein the bottom portion (<NUM>) is a portion that forms a bottom surface of the housing body (<NUM>) and the wall portion (<NUM>) is a portion that forms walls along a peripheral edge of the bottom portion (<NUM>),
wherein the electric components are fixedly installed at a predetermined position on the bottom portion (<NUM>), and
wherein the electric components are chosen among a main relay (20a), a current sensor (20b), a precharge relay (20c), a register (20d).