Patent Description:
Rechargeable batteries having high application characteristics and electrical characteristics such as high energy density according to their products are widely applied to battery vehicles, hybrid vehicles, and electric power storage devices driven by electric driving sources, as well as portable devices. These rechargeable batteries are attracting attention as new energy sources for improving environmental friendliness and energy efficiency in that they do not generate any by-products of energy use, as well as their primary merit that they can drastically reduce the use of fossil fuels.

The commercially available secondary batteries include a nickel cadmium battery, a nickel hydrogen battery, a nickel zinc battery, and a lithium secondary battery, and the lithium secondary battery among them scarcely generates a memory effect compared to the nickel-based secondary battery so it is freely charged and discharged, a self-discharge rate is very low, and an energy density is high.

In general, the lithium secondary battery may be classified into a cylindrical or square-type secondary battery of which the electrode assembly is installed in a metal can, and a pouch-type secondary battery of which the electrode assembly is installed in a pouch of an aluminum laminate sheet, depending on a shape of the exterior material.

Recently, as needs for a large-capacity secondary battery structure increase in addition to the use as an energy storing source of the secondary battery, needs for the battery packs in a medium to large module structure in which battery modules in which a plurality of secondary batteries are coupled in series or in parallel are gathered are increasing. Capacity and outputs of the battery modules are improved by coupling a plurality of battery cells in series or in parallel and configuring a battery cell stacked body. Further, a plurality of battery modules may configure a battery pack when installed together with various control and protection systems such as a battery management system (BMS) or a cooling system.

Particularly, the battery pack has a structure in which a plurality of battery modules are combined, so when some of the battery modules receive an overvoltage or an overcurrent or they are overheated, safety and operation efficiency of the battery pack may be problematic. Particularly, while the capacity of the battery pack is in the increasing trend to improve mileage and energy inside the pack is accordingly increasing, there is a need to design a structure satisfying reinforcing safety standards and obtaining safety of vehicles and drivers. For this purpose, the need for acquiring a structure for preventing an internal thermal runaway in advance, and minimizing corresponding damages when the thermal runaway is generated, is particularly on the rise.

Examples of background art can be found in <CIT>, <CIT>, and <CIT>.

The present invention has been made in an effort to provide a battery pack for delaying a heat propagation phenomenon between battery modules, and a device including the same.

The technical problem to be solved of the present invention is not limited to the above-described problem, and problems not mentioned will be clearly understood by a person of ordinary skill in the art from the present specification and the accompanying drawings.

The invention as defined in the independent claim <NUM> provides a battery pack including: a pack frame; a plurality of first battery modules installed on an upper portion of the pack frame; a plurality of second battery modules installed on a lower portion of the pack frame; and a heat insulating member disposed near a lateral side of the first battery module disposed on an outermost side of the plurality of first battery modules.

The battery pack may further include a side plate disposed near a lateral side of the first battery module disposed on an outermost side of the plurality of first battery modules, wherein the heat insulating member may be attached to the side plate.

The battery pack may further include a horizontal plate disposed between a lower portion of the first battery modules and an upper portion of the second battery modules.

A gas fluid portion may be disposed on an upper portion of the pack frame, and the gas fluid portion may be disposed between the side plate and the horizontal plate.

A gas outlet is formed on an upper side of the pack frame.

The gas outlet may be a gas valve penetrating toward an inside of the pack frame from an upper side of the pack frame.

The first battery module disposed on the outermost side of the first battery modules may be disposed near the gas outlet.

The heat insulating member is disposed on a lateral side disposed near the gas outlet from among lateral sides of the first battery module disposed on the outermost side of the plurality of first battery modules.

A gas fluid portion is disposed on an upper portion of the pack frame, and the gas outlet may be disposed on the gas fluid portion.

The gas fluid portion may be disposed between the heat insulating member and a lateral side of the pack frame.

The number of the second battery modules included in the plurality of second battery modules may be greater than the number of the first battery modules included in the plurality of first battery modules.

The gas fluid portion may be disposed on at least some second battery modules from among the second battery modules.

Another embodiment of the present invention provides a device including the above-described battery pack
According to the embodiments, the battery pack according to the present invention and the device including the same may delay the heat propagation phenomenon between the battery modules in the pack frame because the heat insulating member is attached to the lateral side of the battery module positioned on the outermost side of the plurality of battery modules installed on the upper portion of the pack frame.

The effects of the object of the present invention are not limited to the above-described effects, and effects not mentioned will be clearly understood by a person of ordinary skill in the art from the present specification and the accompanying drawings.

The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown.

In order to clearly describe the present invention, parts that are irrelevant to the description are omitted, and identical or similar constituent elements throughout the specification are denoted by the same reference numerals.

The size and thickness of each element are arbitrarily illustrated for ease of description, and the present disclosure is not necessarily limited to those illustrated in the drawings. The thicknesses of layers, films, panels, regions, etc., are enlarged for clarity. The thicknesses of some layers and regions are exaggerated.

Unless explicitly described to the contrary, the word "comprise" and variations such as "comprises" or "comprising" will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.

The phrase "in a plan view" or "on a plane" means viewing a target portion from the top, and the phrase "in a cross-sectional view" or "on a cross-section" means viewing a cross-section formed by vertically cutting a target portion from the side.

A battery pack according to an embodiment of the present invention will now be described. However, one cross-section of the battery pack will be a reference to be described, but is not limited thereto, and the entire battery pack may be described with the same or similar contents.

<FIG> shows a perspective view of a battery pack an embodiment of the present invention. <FIG> shows an exploded perspective view of a battery pack of <FIG>.

Referring to <FIG> and <FIG>, the battery pack <NUM> according to an embodiment of the present invention includes: pack frames <NUM> and <NUM>; a plurality of first battery modules <NUM> mounted on upper portions of the pack frames <NUM> and <NUM>; and a plurality of second battery modules <NUM> mounted on lower portions of the pack frames <NUM> and <NUM>.

Here, the pack frames <NUM> and <NUM> may include an upper case <NUM> and a lower case <NUM> for receiving a plurality of first battery modules <NUM> and a plurality of second battery modules <NUM>. For example, the upper case <NUM> and the lower case <NUM> may be fastened to each other by a bolt and nut combination.

Further, a lowest end of a plurality of first battery modules <NUM> may be positioned to be higher than a highest end of the second battery modules <NUM>. For example, a plurality of first battery modules <NUM> and a plurality of second battery modules <NUM> may form a layered structure. In other words, a plurality of first battery modules <NUM> may be positioned on an upper layer, and a plurality of the second battery modules <NUM> may be positioned on a lower layer.

Further, the number of the second battery modules <NUM> included in a plurality of second battery modules <NUM> may be greater than the number of the first battery modules <NUM> included in a plurality of first battery modules <NUM>. For example, as shown in <FIG>, two first battery modules <NUM> may be positioned on the upper layer, and four second battery modules <NUM> may be positioned on the lower layer.

Accordingly, regarding the battery pack <NUM> according to the present embodiment, as a plurality of battery modules <NUM> and <NUM> are disposed in a layered structure, the battery modules <NUM> and <NUM> installed in the battery pack <NUM> may be disposed in a more compact way.

A horizontal plate <NUM> positioned between the lower portion of a plurality of first battery modules <NUM> and the upper portion of a plurality of second battery modules <NUM> may be further included. In other words, the horizontal plate <NUM> is provided between a plurality of first battery modules <NUM> positioned on the upper layer and a plurality of second battery modules <NUM> positioned on the lower layer, so a plurality of first battery modules <NUM> and a plurality of second battery modules <NUM> may be distinguished as a layered structure.

Accordingly, the battery pack <NUM> according to the present embodiment includes the horizontal plate <NUM> between a plurality of first battery modules <NUM> and a plurality of second battery modules <NUM> in the pack frames <NUM> and <NUM>, thereby separating a space of the upper layer and the lower layer, and additionally obtaining durability of the battery pack <NUM>. It may physically protect the battery modules <NUM> and <NUM> and other electronic units from external impacts.

Regarding the battery pack <NUM>, a side plate <NUM> may be closely positioned on a lateral side of the first battery module <NUM> positioned on an outermost side of the plurality of first battery modules <NUM>. In other words, the side plate <NUM> may contact the lateral side of the first battery module <NUM> positioned on the outermost side of the plurality of first battery modules <NUM>. For example, the side plate <NUM> may be combined, engaged, or attached to the lateral side of the first battery module <NUM> positioned on the outermost side of the plurality of first battery modules <NUM>.

Here, that which is positioned on the outermost side in the pack frames <NUM> and <NUM> may signify the first battery module <NUM> positioned on the outermost side when a plurality of first battery modules <NUM> are disposed in parallel to each other in the pack frames <NUM> and <NUM>.

The lateral side of the first battery module <NUM> positioned on the outermost side of the plurality of first battery modules <NUM> may be exposed in the pack frames <NUM> and <NUM>. However, in the present embodiment, the side plate <NUM> may be positioned on the lateral side of the first battery module <NUM> positioned on the outermost side of the plurality of first battery modules <NUM> to physically protect the first battery module <NUM> positioned on the outermost side from external impacts.

Regarding the battery pack <NUM>, a heat insulating member <NUM> may be positioned near the lateral side of the first battery module <NUM> positioned on the outermost side of the plurality of first battery modules <NUM>. In detail, the heat insulating member <NUM> may be attached to the side plate <NUM>. The heat insulating member <NUM> may extend along an external side of the side plate <NUM>.

For example, the heat insulating member <NUM> may be made of a material such as super wool. However, without being limited thereto, any types of heat insulating materials are usable.

Accordingly, in the present embodiment, when the heat and the high-temperature gas are generated in the pack frames <NUM> and <NUM>, influences caused by the heat and the high-temperature gas in the pack frames <NUM> and <NUM> for the first battery module <NUM> positioned on the outermost side of the plurality of first battery modules <NUM> may be minimized by the heat insulating member <NUM> attached to the side plate <NUM>.

Further, a gas outlet <NUM> may be formed on upper sides of the pack frames <NUM> and <NUM>. In detail, the gas outlet <NUM> may be formed on the upper side of the upper case <NUM> in the pack frames <NUM> and <NUM>.

For example, the gas outlet <NUM> may be a gas valve penetrating toward insides of the pack frames <NUM> and <NUM> from the upper sides of the pack frames <NUM> and <NUM>. For another example, the gas outlet <NUM> may be a gas valve penetrating toward the inside of the lower case <NUM> from the upper side of the upper case <NUM>. However, a shape of the gas outlet <NUM> is not limited to the valve shape, and any shapes for discharging the gas in the pack frames <NUM> and <NUM> are allowable.

Accordingly, in the present embodiment, when heat and high-temperature gas are generated in the pack frames <NUM> and <NUM>, the heat and high-temperature gas in the pack frames <NUM> and <NUM> may be discharged through the gas outlet <NUM>.

Further, a gas fluid portion <NUM> may be positioned on the upper portions of the pack frames <NUM> and <NUM>. In detail, the gas fluid portion <NUM> may be positioned on the upper portions of the pack frames <NUM> and <NUM>, and the gas fluid portion may be positioned between the side plate <NUM> and the horizontal plate <NUM>.

Further, the gas fluid portion <NUM> may be positioned on at least some second battery modules <NUM> from among a plurality of second battery modules <NUM> installed on the lower layer. In other words, the gas fluid portion <NUM> may signify a space in which a plurality of first battery modules <NUM> installed on the upper layers of the pack frames <NUM> and <NUM> are not positioned.

When an ignition event is generated by some battery modules <NUM> and <NUM>, heat and high-temperature gas may be generated in the pack frames <NUM> and <NUM>. Here, regarding the battery pack <NUM> according to the present embodiment, the gas fluid portion <NUM> may be positioned on the upper portions of the pack frames <NUM> and <NUM> to receive the heat and the high-temperature gas by the gas fluid portion <NUM>. Hence, the gas fluid portion <NUM> may delay discharging of the heat and high-temperature gas in the pack frames <NUM> and <NUM> to the outside.

Further, the gas outlet <NUM> may be positioned on the gas fluid portion <NUM>. That is, when an ignition event is generated by some battery modules <NUM> and <NUM>, the heat and the high-temperature gas may move to the gas fluid portion <NUM> in the pack frames <NUM> and <NUM>, and the heat and the high-temperature gas received into the gas fluid portion <NUM> may be discharged to the outside through the gas outlet <NUM>.

Referring to <FIG>, the first battery module <NUM> positioned on the outermost side of the plurality of first battery modules <NUM> may be positioned near the gas outlet <NUM>. The heat insulating member <NUM> may be positioned on a lateral side provided near the gas outlet <NUM> from among the lateral side of the first battery module <NUM> positioned on the outermost side of the plurality of first battery modules <NUM>. The gas fluid portion <NUM> may be positioned between the heat insulating member <NUM> and the lateral sides of the pack frames <NUM> and <NUM>.

The first battery module <NUM> positioned on the outermost side of the plurality of first battery modules <NUM> may be positioned near a path on which the heat and the high-temperature gas in the pack frames <NUM> and <NUM> are discharged through the gas outlet <NUM> and the gas fluid portion <NUM>. However, because of the heat insulating member <NUM> attached to the side plate <NUM>, the influence caused by the path on which the heat and the high-temperature gas are discharged for the first battery module <NUM> positioned on the outermost side may be minimized.

<FIG> shows a perspective view of first battery module included in a battery pack of <FIG>.

Referring to <FIG>, in an embodiment of the present invention, the first battery module <NUM> may include a plurality of battery cells <NUM>. In detail, the battery cells <NUM> may be stacked in a predetermined direction and may be installed in the module frame <NUM> to thus configure the first battery module <NUM>.

The battery cells <NUM> have no specific limits in their types so they may be pouch-type rechargeable batteries or square-type rechargeable batteries, and they are preferably pouch-type rechargeable batteries.

The first battery module <NUM> has been exemplified to describe the battery module according to the present invention so it may have an equivalent or similar structure to the second battery module <NUM> (or the first battery module <NUM> described with reference to <FIG>).

<FIG> shows a cross-sectional view with respect to a line A-A' of <FIG>. <FIG> shows a heat propagation path when some battery modules generate cell events in a cross-section of <FIG>.

Referring to <FIG> and <FIG>, regarding the battery pack <NUM> according to the present embodiment, a cell event CE may be generated by some second battery modules <NUM> from among a plurality of second battery modules <NUM>. Here, the cell event CE may signify that abnormal phenomena such as an overvoltage, an overcurrent, or overheating in the battery modules <NUM> and <NUM> are generated, and a high temperature and a gas are generated by the battery modules <NUM> and <NUM>.

Hereinafter, it will be assumed that a cell event CE is generated by the second battery module <NUM>, and a case in which the cell event CE is generated by the first battery module <NUM> will also be described in the same or similar way.

Referring to <FIG>, it is found that the cell event CE is generated by some second battery modules <NUM> from among a plurality of second battery modules <NUM>, regarding the battery pack <NUM> according to the present embodiment. Referring to <FIG>, by the heat and the high-temperature gas generated by the second battery module <NUM> having generated the cell event CE, the cell event CE may be propagated to the adjacent second battery module <NUM>.

A horizontal plate <NUM> may be positioned between a plurality of first battery modules <NUM> and a plurality of second battery modules <NUM>, thereby preventing the heat and the high-temperature gas generated by the second battery module <NUM> having generated the cell event CE from directly being transmitted to the first battery module <NUM>, or further delaying a transmitting time.

The high-temperature gas generated by the second battery module <NUM> having generated the cell event CE may move to the gas fluid portion <NUM> positioned in the pack frames <NUM> and <NUM>, and the high-temperature gas having moved to the gas fluid portion <NUM> may be discharged to the outside through the gas outlet <NUM>.

The first battery module <NUM> positioned on the outermost side of the plurality of first battery modules <NUM> may be positioned near the path on which the high-temperature gas generated by the second battery module <NUM> having generated the cell event CE is discharged through the gas outlet <NUM> and the gas fluid portion <NUM>.

However, as shown in <FIG>, regarding the battery pack <NUM> according to the present embodiment, by the heat insulating member <NUM> attached to the side plate <NUM>, the influence caused by the path on which the heat and the high-temperature gas are discharged for the first battery module <NUM> positioned on the outermost side of the plurality of first battery modules <NUM> may be minimized. That is, the time for propagating the cell event CE may be efficiently delayed by minimizing heat transfer to the first battery module <NUM> from the second battery module <NUM> having generated the cell event CE.

<FIG> shows a heat propagation path when some battery modules generate cell events in a battery pack according to a comparative example.

Differing from what is described in the above, referring to <FIG>, in the case of the battery pack <NUM> according to a comparative example, when a cell event CE is generated by some second battery modules <NUM> from among a plurality of second battery modules <NUM>, the cell event CE may be propagated to the adjacent second battery module <NUM>. As the high-temperature gas generated by the second battery module <NUM> moves to the gas fluid portion <NUM>, heat caused by the high-temperature gas having moved to the gas fluid portion <NUM> may be transmitted to the first battery module <NUM> positioned on the outermost side of the plurality of first battery modules <NUM>.

That is, in the case of the battery pack <NUM> according to a comparative example, the first battery module <NUM> positioned on the outermost side of the plurality of first battery modules <NUM> is easily exposed to the heat and the high-temperature gas in the pack frames <NUM> and <NUM> so the cell event CE generated by some battery modules <NUM> and <NUM> may be easily propagated. In comparison to this, as described above, the battery pack <NUM> according to an embodiment of the present invention may minimize heat transfer to the first battery module <NUM> from the second battery module <NUM> having generated the cell event CE, and may efficiently delay the time for propagating the cell event CE.

The battery pack according to the present embodiment may be applied to various devices. The devices include transport means such as electric bicycles, electric vehicles, and hybrid vehicles, but the present invention is not limited thereto, and it may be applied to various devices that use the battery module and the battery pack including the same, which also belongs to the scope of the present invention.

Claim 1:
A battery pack (<NUM>) comprising:
a pack frame (<NUM>, <NUM>);
a plurality of first battery modules (<NUM>) installed on an upper portion of the pack frame (<NUM>, <NUM>);
a plurality of second battery modules (<NUM>) installed on a lower portion of the pack frame (<NUM>, <NUM>); and
a heat insulating member (<NUM>) disposed near a lateral side of the first battery module (<NUM>) disposed on an outermost side of the plurality of first battery modules (<NUM>),
characterized in that a gas outlet (<NUM>) is formed on an upper side of the pack frame (<NUM>, <NUM>),
wherein the heat insulating member (<NUM>) is disposed on a lateral side disposed near the gas outlet (<NUM>) from among lateral sides of the first battery module disposed on the outermost side of the plurality of first battery modules (<NUM>),
wherein a gas fluid portion (<NUM>) is disposed on an upper portion of the pack frame, and
wherein the gas outlet (<NUM>) is disposed on the gas fluid portion (<NUM>).