Patent Description:
Secondary batteries that are easy to apply according to product groups and have electrical characteristics such as high energy density are commonly applied to not only portable devices, but also electric vehicles (EVs) or hybrid electric vehicles (HEVs) driven by electric drive sources, and electric storage devices. The secondary batteries are attracting attention as a new energy source for improving eco-friendliness and energy efficiency in that they do not generate any by-products from the use of energy as well as the primary advantage of dramatically reducing the use of fossil fuels.

A battery pack applied to an electric vehicle or the like has a structure in which a plurality of cell assemblies having a plurality of unit cells are connected in series to obtain a high output. In addition, the unit cell may be repeatedly charged and discharged by an electric chemical reaction between components, including positive and negative electrode current collectors, a separator, an active material, an electrolyte, and the like.

Meanwhile, as the need for a large-capacity structure, including its use as an energy storage source, increases recently, the demand for a battery pack having a multi-module structure in which a plurality of battery modules, each having a plurality of secondary batteries connected in series and/or parallel, are grouped is increasing.

It is important that the battery pack with a multi-module structure applied to an electric vehicle is designed to have as high energy density per unit volume as possible because of the restriction on an installation space inside the vehicle and to easily dissipate the heat generated by the intensively arranged battery modules most of all. Among various methods of dissipating heat generated from the battery module, an indirect water cooling method as disclosed in <CIT> or <CIT> is widely used.

Seeing the cooling configuration of the indirect water-cooled battery pack according to the prior art, a heatsink is coupled to an upper surface of a tray forming a bottom surface of a pack case, a thermal pad is interposed on the heatsink, and then a battery module is mounted on the thermal pad so that the heat of the battery module is dissipated to the outside through the thermal pad and the heatsink.

However, the battery pack according to the prior art as disclosed in <CIT> or <CIT> may not be easily assembled since the number of components and fixing structures required to fix the heatsink to the upper surface of the tray increases and the layout of an inlet hose and an outlet hose for supplying a coolant to the heatsink is difficult.

In addition, even if the heatsink is fixed to the tray with a rivet or the like, the entire lower surface of the heatsink is not completely adhered to the upper surface of the tray, so a gap exists therebetween. For this reason, if an external shock is applied to the tray so that the tray vibrates, the heatsink may be damaged. As this situation continues, a crack may occur in the heatsink, resulting in coolant leakage.

Accordingly, there is a demand for the development of a battery pack having a new cooling configuration that may supplement the problems of the water-cooled battery pack according to the prior art.

Further prior art is described in <CIT> and <CIT>.

The present disclosure is designed to solve the problems of the related art, and therefore the present disclosure is directed to providing a battery pack capable of reducing the number of cooling components included in a pack housing and simplifying the assembly process by using an efficient the cooling path configuration.

In addition, the present disclosure aims is directed to integrating a cooling path configuration having an easy layout and excellent durability into the pack housing stably.

According to the herein claimed invention, there is provided a battery pack, comprising: battery modules provided with a heatsink; a pack housing including a floor panel having an upper surface on which the battery modules are placed and a lower surface in which coolant channels for supplying and discharging a coolant to/from the heatsink of the battery modules are provided, and a base plate disposed below the floor panel in a layered form; and a coolant supply pipe configured to selectively communicate with the coolant channels and be coupled to an upper surface of the floor panel and disposed along a right side line of the floor panel; and a coolant discharge pipe configured to selectively communicate with the coolant channels and be coupled to the upper surface of the floor panel and disposed along a left side line of the floor panel, wherein the coolant channels have a lower end fixedly coupled to the base plate, and wherein the coolant channels are provided in a rectangular tube shape to extend from the right side line to the left side line, and the lower end of the coolant channel in a rectangular tube shape is joined to the base plate by friction stir welding.

The floor panel may further include a support member formed on the lower surface of the floor panel to protrude as much as a thickness of the coolant channel.

The support member may have a longitudinal section of a '<NUM>' shape to extend from the right side line to the left side line.

The heatsink may is configured as a bottom plate of the battery module.

The coolant channels may include a first coolant channel configured to introduce a coolant into any one battery module and a second coolant channel configured to discharge a coolant from the any one battery module, and the first coolant channel and the second coolant channel may be provided in a plurality of pairs, and the plurality of pairs of first coolant channels and second coolant channels may be arranged at predetermined pattern intervals along a front and rear direction of the pack housing.

The interval between the first coolant channel and the second coolant channel provided in a pair may be smaller than a width of the battery module.

In a central area of the floor panel, two injection ports may be provided for one first coolant channel and two discharge ports are provided for one second coolant channel.

The battery modules may be arranged such that two battery modules face each other, respectively, and two battery modules facing each other may be configured such that a coolant is supplied thereto through one of the two injection ports, respectively, and a coolant is discharged therefrom through one of the two discharge ports, respectively.

The pack housing may further include a front frame forming a front wall, a rear frame forming a rear wall, a right side frame forming a right wall and a left side frame forming a left wall, which are vertically coupled to the floor panel, respectively.

The right side frame may include a first pipe protection membrane configured to cover the coolant supply pipe, and the left side frame may include a second pipe protection membrane configured to cover the coolant discharge pipe.

The first pipe protection membrane may include a first horizontal plate disposed on the coolant supply pipe and a first vertical plate bent at one end of the first horizontal plate to extend downward so that an end line of the first vertical plate is welded to the floor panel, and the second pipe protection membrane may include a second horizontal plate disposed on the coolant discharge pipe and a second vertical plate formed at one end of the second horizontal plate to extend downward so that an end line of the second vertical plate is welded to the floor panel.

At least one side of the battery modules may be fastened to the first horizontal plate or the second horizontal plate by a bolt.

The floor panel, the front frame, the rear frame, the right side frame and the left side frame may be an aluminum extrusion structure, respectively.

Meanwhile, in another aspect of the present disclosure, there may be provided a vehicle, comprising the battery pack described above.

According to an embodiment of the present disclosure, it is possible to provide a battery pack capable of reducing the number of cooling components included in the pack housing and simplifying the assembly process by using an efficient cooling path configuration.

More specifically, since the battery pack of the present disclosure includes battery modules integrated with a heatsink such as a cooling plate and a pack housing having coolant channels for supplying or discharging a coolant to/from the battery modules, the number of components of a cooling device or the number of components for fixing them to be installed inside the pack housing is reduced, thereby greatly simplifying the assembly process, compared to the prior art.

In addition, in the battery pack of the present disclosure, since the coolant channels are connected to the base plate and the cooling path structure is designed stably, the reliability of the cooling function may be maintained against shock or vibration.

Other effects of the present disclosure may be understood by the following description and will be more clearly understood by the embodiments of the present disclosure.

<FIG> is a schematic perspective view showing a battery pack according to an embodiment of the present disclosure, <FIG> is an exploded perspective view schematically showing the battery pack of <FIG>, and <FIG> is a perspective view showing a pack housing in which battery modules of <FIG> are placed.

Referring to these drawings, a battery pack <NUM> according to an embodiment of the present disclosure includes a plurality of battery modules <NUM>, an electric component assembly <NUM>, a pack housing <NUM> and a pack cover <NUM>.

The battery module <NUM> may include a cell assembly (not shown) formed by stacking a plurality of battery cells (not shown), a module case <NUM> for accommodating the cell assembly, and a heatsink <NUM> (see <FIG>).

For example, a pouch-type secondary battery may be employed as the battery cell, and the pouch-type secondary batteries may be configured to be erected vertically such that their wide surfaces are oriented upward and downward, and the pouch-type secondary batteries may be stacked in one direction to form a cell assembly.

The module case <NUM> may be configured in a rectangular box shape to surround the outside of the cell assembly so that the cell assembly may be held therein. In order to sufficiently protect the cell assembly from swelling of the pouch-type secondary battery and external impact, it may be preferable that the module case <NUM> is made of a metal material with high mechanical rigidity.

The heatsink <NUM> (see <FIG>) refers to an object that absorbs heat from another object by thermal contact and dissipates the heat, and may be provided in the form of a plate-shaped body having a channel therein. The heatsink <NUM> may be mounted under a bottom plate, which is a part of the module case <NUM>, or may be provided to serve as a bottom plate of the module case <NUM> by itself to be integrated with the battery module <NUM>.

When the battery module <NUM> is placed on an upper surface of a floor panel <NUM>, explained later, the heatsink <NUM> may have an entrance vertically connected to any one coolant channels 313A, 313B and an exit connected vertically to the other coolant channel 313A, 313B.

As will be described in detail later, a coolant may absorb heat from the battery cells while circulating along the channel formed inside the heatsink <NUM> through the entrance of the heatsink <NUM> in the any one coolant channels 313A, 313B, and discharge the heat out of the heatsink <NUM> through the exit of the heatsink <NUM> along the other coolant channels 313A, 313B.

Meanwhile, in order to increase the capacity and output of the battery pack <NUM>, a large number of battery modules <NUM> are required, and accordingly, the number of parts such as inter-bus bars for wiring between the battery modules <NUM>, harness cables for transmitting voltage data and temperature data of each battery module <NUM> to a BMS (Battery Management System), connectors, or the like increases.

The battery pack <NUM> of this embodiment adopts a large-capacity battery module <NUM> whose size is <NUM> to <NUM> times larger than an existing general battery module <NUM>, and compared with the conventional battery pack having the same capacity and output, the total number of battery modules <NUM> mounted in the pack housing <NUM> is small. In other words, by increasing the capacity of the battery module <NUM> so that a smaller number of large-capacity battery modules <NUM> are mounted in the pack housing <NUM>, the number of parts such as inter-bus bars, harness cables and connectors may be reduced.

In addition, in the battery pack <NUM> of the present disclosure in which large-capacity battery modules <NUM> are mounted, the space occupancy purely occupied by battery cells may be further increased than the space occupancy occupied by the module cases <NUM> and its accessories inside the pack housing <NUM>, compared to a conventional battery pack <NUM> in which general battery modules <NUM> are mounted, and thus there is an advantage in that the energy density per unit volume may be significantly improved.

For reference, the high-capacity battery module <NUM> of this embodiment may include approximately <NUM> long cells per unit. For reference, the existing battery module <NUM> to which pouch-type secondary batteries are applied has a width (in a stacking direction of the pouch cells) of about <NUM> to <NUM>, but the large-capacity battery module <NUM> according to this embodiment has a width of about <NUM>.

The electric component assembly <NUM> may include a relay device, a current sensor, a fuse, a BMS, a MSD (Manual Service Disconnector), and the like. The relay device is a switching component that selectively opens and closes a charging/discharging path through which a current flows, and may block the flow of a charging/discharging current when an abnormal situation occurs in the battery pack <NUM>. The BMS refers to a battery management system that overall controls the charging/discharging operation of the battery modules <NUM>, and may be regarded as a component commonly included in the battery pack <NUM>. In addition, the MSD (Manual Service Disconnector) is a system to selectively cut off the power of a high-voltage battery by a physical method, and when necessary, the MSD disconnects a service plug to cut off the power.

The electric component assembly <NUM> as above may be packaged so as not to be exposed to the outside by the pack housing <NUM> and the pack cover <NUM> together with the battery modules <NUM>.

The pack housing <NUM> provides a space to accommodate the battery modules <NUM> and the electric component assembly <NUM> therein, and may be regarded as a structure including a bracket <NUM> or mounting structures <NUM>, <NUM> to be coupled to a vehicle body.

The pack housing <NUM> provides a mechanical support to the battery modules <NUM> and the electric component assembly <NUM> and protects them from external shocks, so the pack housing <NUM> is preferably made of a metal material with high rigidity.

Specifically, as shown in <FIG> and <FIG>, the pack housing <NUM> according to this embodiment may include a lower frame <NUM> provided in a wide plate shape on which the battery modules <NUM> may be placed, as well as a front frame <NUM>, a rear frame <NUM>, a right side frame <NUM> and a left side frame <NUM> vertically coupled along an edge of the lower frame <NUM> to form walls, and cross beams <NUM> coupled to both ends of the right side frame <NUM> and the left side frame <NUM>.

The lower frame <NUM>, the front frame <NUM>, the rear frame <NUM>, the right side frame <NUM>, the left side frame <NUM> and the cross beam <NUM> are an aluminum extrusion structure, respectively, and the pack housing <NUM> may be made by welding and bolting the frames.

For example, the frames are manufactured by extruding aluminum with empty spaces and ribs mixed therein, and the frames are welded to form the pack housing <NUM>, thereby reducing the weight of the pack housing <NUM> and maintaining the mechanical rigidity at a reliable level or higher.

Meanwhile, the coolant channels 313A, 313B are integrated in the lower frame <NUM> that constitutes the pack housing <NUM> of the present disclosure. Hereinafter, the configuration of the lower frame <NUM> will be described in detail.

The lower frame <NUM> according to the present disclosure may be provided in a double-layer structure including a floor panel <NUM> and a base plate <NUM>. For example, the base plate <NUM> is formed below the floor panel <NUM> in a layered form, and the floor panel <NUM> and the base plate <NUM> may be provided to have the same area.

As shown in <FIG> and <FIG>, the floor panel <NUM> includes an upper surface on which the battery modules <NUM> may be placed, coolant channels 313A, 313B for supplying or discharging a coolant to/from the heatsink <NUM> of the battery modules <NUM>, and a lower surface on which a support member <NUM> is formed to maintain an interlayer interval with the base plate <NUM>.

The upper surface of the floor panel <NUM> is formed with a flat and wide surface so that the plurality of battery modules <NUM> may be arranged in a matrix on the same plane, and the lower surface of the floor panel <NUM> may be configured such that the coolant channels 313A, 313B and the support members <NUM> protrude in a tube or bar shape to form a convex pattern.

The coolant channels 313A, 313B are provided in a rectangular tube shape extending from a right side line to a left side line (in the Y-axis direction) of the floor panel. The coolant channels 313A, 313B serve as passages for guiding the flow of coolant from the left side to the right side of the floor panel or from the right side to the left side of the floor panel.

In addition, the coolant channels 313A, 313B are configured such that their lower ends are fixedly coupled to the base plate <NUM>. Referring to <FIG>, in this embodiment, the bottom surfaces of the coolant channels 313A, 313B are provided in a rectangular tube shape and the base plate <NUM> are placed to be overlapped and then joined to each other by friction stir welding W.

For example, even if there is a slight gap between the coolant channels 313A, 313B and the base plate <NUM>, there is a risk that the coolant channels 313A, 313B may be continuously hit and damaged when the base plate <NUM> vibrates. Accordingly, in the present disclosure, in order to prevent this situation, the coolant channels 313A, 313B and the base plate <NUM> are joined so that the coolant channels 313A, 313B are not hit when the base plate <NUM> vibrates.

For reference, the floor panel <NUM> including the coolant channels 313A, 313B may be easily divided into <NUM> parts for easy aluminum extrusion, and the base plate <NUM> corresponding to a bottom end of the pack housing <NUM> may be made of a steel plate to maximize rigidity.

In general, different kinds of metals such as aluminum and steel are difficult to attach to each other and are often joined using a rivet. However, the joined surface without a rivet may float, resulting in incomplete contact. In order to solve the problem of the rivet method, in this embodiment, friction stir welding is used such that the coolant channels 313A, 313B are completely joined to the base plate <NUM> along an extension direction thereof.

In other words, after the lower surfaces of the coolant channels 313A, 313B are overlapped with the base plate <NUM>, the base plate <NUM> may be pressed, rotated and pressurized by pushing a tool such that the coolant channels 313A, 313B and the base plate <NUM> are joined. That is, by the pressure exceeding a certain limit, the base plate <NUM> and the lower surfaces of the coolant channels 313A, 313B are transformed like a liquid from a solid state so that the two metals are attached to each other.

The friction stir welding does not require a separate welding material and is very eco-friendly because harmful rays and harmful gases are not generated.

The support member <NUM> has a longitudinal section of a '<NUM>' shape to extend from the right side line to the left side line in parallel with the coolant channels 313A, 313B, and friction stir welding may also be applied to the base plate <NUM> like the coolant channels 313A, 313B. In this way, the floor panel <NUM> and the base plate <NUM> may be fixedly coupled firmly to form the lower frame <NUM>.

Referring to <FIG> along with <FIG> and <FIG>, the battery pack <NUM> according to the present disclosure further includes a coolant supply pipe <NUM> for supplying a coolant to the coolant channels 313A, 313B, and a coolant discharge pipe <NUM> for discharging a coolant from the coolant channels 313A, 313B.

The coolant supply pipe <NUM> may be coupled to the upper surface of the floor panel <NUM> and may be arranged along the right side line of the floor panel <NUM>. In addition, an inlet port <NUM> of the coolant supply pipe <NUM> may be exposed out of the pack housing <NUM> through the front frame <NUM>, and a coolant is injected into the inlet port <NUM> of the coolant supply pipe <NUM> from the outside to flow into the pack housing <NUM>.

The coolant supply pipe <NUM> may be covered by the right side frame <NUM> while the right side frame <NUM> is being coupled to the floor panel <NUM>. To this end, the right side frame <NUM> may include a first pipe protection membrane <NUM> provided to cover the coolant supply pipe <NUM>. Referring to <FIG>, the first pipe protection membrane <NUM> may include a first horizontal plate 341a disposed on the coolant supply pipe <NUM> and a first vertical plate 341b bent at one end of the first horizontal plate 341a to extend downward so that an end line thereof is coupled to the floor panel <NUM>.

The first pipe protection membrane <NUM> may be configured such that the first horizontal plate 341a and the first vertical plate 341b are elongated along the right side line of the floor panel <NUM> to cover the entire coolant supply pipe <NUM>. In addition, the end line of the first vertical plate 341b is welded to the floor panel <NUM>, so that, even when a coolant leaks from the coolant supply pipe <NUM>, the coolant does not flow out to the upper surface of the floor panel <NUM>, thereby preventing a short circuit accident.

Also, the first horizontal plate 341a may be used as a place for fixing the battery module <NUM>. For example, as shown in <FIG>, the battery module <NUM> may include a fastening block <NUM> configured to protrude from the module casing and provided so that a bolt B is inserted therein in a vertical direction. The fastening block <NUM> may be provided at a height capable of being placed on the upper surface of the first horizontal plate 341a inside the battery module <NUM>. The battery modules <NUM> may be fixed to the right side frame <NUM> by fastening the bolt B to the fastening block <NUM> placed on the first horizontal plate 341a.

The coolant discharge pipe <NUM> may be coupled to the upper surface of the floor panel <NUM> and may be provided to be disposed along the left side line of the floor panel <NUM>.

An outlet port <NUM> of the coolant discharge pipe <NUM> may be provided to be exposed out of the pack housing <NUM> through the front frame <NUM>. The coolant inside the pack housing <NUM> may exit to the outside toward the front frame <NUM> through the outlet port <NUM> of the coolant discharge pipe <NUM>.

Similar to the coolant supply pipe <NUM> described above, the coolant discharge pipe <NUM> may be covered by the left side frame <NUM> not to be exposed to the outside while the left side frame <NUM> is being coupled to the floor panel <NUM>.

To this end, the left side frame <NUM> may include a second pipe protection membrane <NUM> provided to cover the coolant discharge pipe <NUM>. The second pipe protection membrane <NUM> may include a second horizontal plate 351a disposed on the coolant discharge pipe <NUM> and a second vertical plate 351b bent at one end of the second horizontal plate 351a to extend downward so that an end line thereof is welded to the floor panel <NUM>.

That is, the second pipe protection membrane <NUM> may be provided symmetrically with the first pipe protection membrane <NUM> described above, and plays a role of protecting the coolant discharge pipe <NUM> from external impact and preventing a short circuit accident by blocking a coolant not to flow out the upper surface of the floor panel <NUM> even if the coolant leaks.

In addition, the second horizontal plate 351a may be bolted to the fastening block <NUM> of the battery module <NUM>, similar to the first horizontal plate 341a described above, to fix the battery module <NUM>.

Hereinafter, the cooling path structure of the battery pack <NUM> according to the present disclosure will be described in more detail with reference to <FIG> and <FIG> and <FIG> again.

The coolant channels 313A, 313B may be disposed to be spaced apart from each other in the following pattern along the front and rear direction (X-axis direction) of the pack housing <NUM>.

Referring to <FIG> and <FIG>, the coolant channels 313A, 313B may be classified into a first coolant channel 313A, which is the coolant channel 313A, 313B for introducing a coolant into any one battery module <NUM>, and a second coolant channel 313B, which is the coolant channel 313A, 313B for discharging a coolant from the any one battery module <NUM>. The first coolant channel 313A and the second coolant channel 313B may be provided in a plurality of pairs. The interval between the pair of the first coolant channel 313A and the second coolant channel 313B may be determined to be smaller than the width of the battery module <NUM>. In this embodiment, three pairs of coolant channels 313A, 313B are provided at the lower surface of floor panel <NUM> in the above-described pattern.

The coolant supply pipe <NUM> and the coolant discharge pipe <NUM> are connected to selectively communicate with the coolant channels 313A, 313B.

More specifically, the coolant supply pipe <NUM> is connected to communicate with the first coolant channels 313A, and the coolant discharge pipe <NUM> is connected to communicate with the second coolant channels 313B.

At this time, the coolant supply pipe <NUM> and the first coolant channel 313A may be connected by a pipe connector <NUM>, respectively. For example, as shown in <FIG>, a hole may be provided in a vertical direction at a right edge of the first coolant channel 313A, and a pipe connector <NUM> may be interposed between the hole and the coolant supply pipe <NUM>. The coolant discharge pipe <NUM> may be connected to communicate only with the second coolant channels 313B in the same way as the coolant supply pipe <NUM>.

According to this configuration, the coolant flowing in the coolant supply pipe <NUM> may move only to the first coolant channels 313A, and the coolant flowing in the second coolant channel 313B may move only to the coolant discharge pipe <NUM>.

Referring to <FIG> and <FIG>, in a central area of the floor panel <NUM>, two injection ports P1 may be provided for one first coolant channel 313A, and two discharge ports P2 may be provided for one second coolant channel 313B.

The injection port P1 has a hole shape communicating vertically with the inner space of the first coolant channel 313A, and a sealing material may be provided around the hole. One of the two injection ports P1 may be positioned at a right side with respect to a (virtual) center line in the front and rear direction of the floor panel <NUM> and the other one may be positioned on a left side.

The discharge port P2 may be provided in the same structure as the injection port P1 to communicate with the inner space of the second coolant channel 313B in a vertical direction. Therefore, the injection port P1 and the discharge port P2 are alternately provided along the front and rear direction (X-axis direction) of the floor panel <NUM>.

That is, in this embodiment, six injection ports P1 and six discharge ports P2 are provided at the upper surface of the floor panel <NUM>, and two injection ports P1 and two discharge ports P2 are alternately provided in the front and rear direction (X- axis direction), repeatedly.

In addition, six battery modules <NUM> according to this embodiment (see <FIG>) are provided in total, and they are arranged in two rows and three columns such that every two battery modules <NUM> face each other based on the center line of the floor panel <NUM>.

The bottom surface of each battery module <NUM> includes a heatsink <NUM>, the heatsink <NUM> may have an entrance and an exit (not shown) spaced apart from each other in the width direction of the battery module <NUM> so as to be vertically inserted into the injection port P1 and the discharge port P2 of the floor panel <NUM>.

Each of two battery modules 100A, 100B arranged to face each other may receive a coolant through one of two injection ports P1 communicating with the same first coolant channel 313A and discharge a coolant through one of two discharge ports P2 communicating with the same second coolant channel 313B.

In other words, as shown in <FIG>, the coolant flowing through the coolant supply pipe <NUM> may be branched into three first coolant channels 313A and introduced into the heatsink <NUM> of the battery module <NUM> through the injection port P1. In addition, the coolant absorbing heat from the heatsink may be discharged to the second coolant channel 313B through the discharge port P2.

That is, the six battery modules <NUM> are placed on the floor panel <NUM> such that the entrance and exit (not shown) of each heatsink <NUM> are connected to the injection port P1 and the discharge port P2 of the floor panel <NUM>. Accordingly, for all of the six battery modules, the battery cells accommodated therein may be cooled by a coolant flowing in the order of the coolant supply pipe <NUM> → the first coolant channel 313A → each battery module <NUM> → the second coolant channel 313B → the coolant discharge pipe <NUM>.

As described above, in the battery pack <NUM> of the present disclosure, the coolant channels 313A, 313B, the injection port P1 and the discharge port P2 capable of supplying a coolant to the battery modules <NUM> or discharging a coolant from the battery modules <NUM> are integrated at the floor panel <NUM>, and the heatsink <NUM> is integrated with the battery module <NUM>. The battery pack <NUM> of the present disclosure configured as above has no other cooling parts that should be fixed or installed in the pack housing <NUM>, except for the coolant supply pipe <NUM> and the coolant discharge pipe <NUM>, so the assembly process of the battery pack <NUM> may be significantly simplified compared to the prior art.

In addition, the coolant supply pipe <NUM> and the coolant discharge pipe <NUM> are covered and protected by the right side frame <NUM> and the left side frame <NUM>, respectively, and the coolant channels 313A, 313B are joined to the base plate <NUM> by friction stir welding, so the cooling path may be maintained stably against shock or vibration.

Meanwhile, the battery pack <NUM> according to the present disclosure may be included as a power energy source of a vehicle such as an electric vehicle or a hybrid electric vehicle. That is, the vehicle according to the present disclosure may include the battery pack <NUM> described above.

Claim 1:
A battery pack (<NUM>), comprising:
battery modules (<NUM>) provided with a heatsink (<NUM>);
a pack housing (<NUM>) including a floor panel (<NUM>) having an upper surface on which the battery modules (<NUM>) are placed and a lower surface in which coolant channels (313A, 313B) for supplying and discharging a coolant to/from the heatsink (<NUM>) of the battery modules (<NUM>) are provided, and a base plate (<NUM>) disposed below the floor panel (<NUM>) in a layered form; and
a coolant supply pipe (<NUM>) configured to selectively communicate with the coolant channels (313A, 313B) and be coupled to an upper surface of the floor panel (<NUM>) and disposed along a right side line of the floor panel (<NUM>); and
a coolant discharge pipe (<NUM>) configured to selectively communicate with the coolant channels (313A, 313B) and be coupled to the upper surface of the floor panel (<NUM>) and disposed along a left side line of the floor panel (<NUM>),
wherein the coolant channels (313A, 313B) have a lower end fixedly coupled to the base plate (<NUM>), characterized in that
the coolant channels (313A, 313B) are provided in a rectangular tube shape to extend from the right side line to the left side line, and the lower end of the coolant channel (313A, 313B) in a rectangular tube shape is joined to the base plate (<NUM>) by friction stir welding.