Battery module

A battery module including a plurality of battery cells spaced apart in a first direction, and a barrier between adjacent battery cells of the plurality of battery cells, the barrier including a plate, and a protrusion extending from the plate in the first direction and contacting the adjacent battery cells, the protrusion including an elastomer.

BACKGROUND

Aspects of embodiments of the present invention relate to a battery module, and more particularly, to a battery module including a plurality of battery cells and a barrier disposed between the battery cells.

2. Description of the Related Art

Recently, a high-output battery module using a high energy density nonaqueous electrolyte is being developed, and the high-output battery module is realized by a high-capacity battery module formed by connecting a plurality of battery cells in series so that the battery module may be used for devices using high power, such as a driving motor of an electric car.

A battery cell includes an electrode assembly formed of a positive plate, a negative plate, and an electrolyte and generates energy through an electrochemical reaction between the plates and the electrolyte. Here, gas may be generated in the battery cell due to a side reaction of the electrochemical reaction.

The gas may deform an external appearance of the battery cell and affect a shape of the battery module constituted by a plurality of arranged battery cells, interrupting or preventing secure fixing of the battery cells.

SUMMARY

According to an aspect of embodiments of the present invention, a battery module is light due to a novel barrier.

According to another aspect of embodiments of the present invention, a battery module includes a barrier configured to effectively control swelling of a battery cell.

According to an embodiment of the present invention, a battery module includes a plurality of battery cells spaced apart in a first direction, and a barrier between adjacent battery cells of the plurality of battery cells, the barrier including a plate, and a protrusion extending from the plate in the first direction and contacting the adjacent battery cells, the protrusion including an elastomer.

In one embodiment, the plate has an opening formed therethrough in the first direction, and the protrusion extends through the opening. The protrusion may include a first head contacting a first battery cell of the adjacent battery cells, and a connecting member coupled to the first head and extending through the opening.

The protrusion may further include a second head coupled to an end of the connecting member opposite the first head, the second head contacting a second battery cell of the adjacent battery cells. In one embodiment, the first head is formed of a first material, and the second head is formed of a second material different than the first material.

In one embodiment, the connecting member includes a first connecting member portion coupled to the first head, and a second connecting member portion coupled to the second head, and the first and second connecting member portions have substantially a same length in the first direction, the length of the first and second connecting member portions being less than or equal to approximately half of a thickness of the plate in the first direction.

The first head, the second head, and the connecting member may be integrally formed.

In one embodiment, the opening includes a plurality of openings arranged in a plurality of lines spaced apart from one another at intervals, the protrusion includes a plurality of protrusions extending through respective ones of the plurality of openings, and first heads of the plurality of protrusions arranged in at least one first line of the plurality of lines are formed of a first material, and first heads of the plurality of protrusions arranged in at least one second line of the plurality of lines adjacent and alternating with the at least one first line are formed of a second material different than the first material. The protrusions may further include second heads coupled to ends of the connecting members opposite the first heads, the second heads contacting a second battery cell of the adjacent battery cells, and the second heads of the plurality of protrusions arranged in the at least one first line may be formed of the second material, and the second heads of the plurality of protrusions arranged in the at least one second line may be formed of the first material.

The connecting member may contact a second battery cell of the adjacent battery cells.

A size of the connecting member may be substantially the same as a size of the opening.

The first head and the connecting member may be integrally formed.

In one embodiment, the first head includes a first end connected to the connecting member and a second end spaced from the connecting member, and a diameter of the first head at the first end is greater than a diameter of the opening, and a diameter of the first head at the second end is substantially the same as the diameter of the opening.

The connecting member may include a spring.

The opening may include a plurality of openings arranged in a plurality of lines spaced apart from one another, and the protrusion may include a plurality of protrusions extending through respective ones of the plurality of openings.

In one embodiment, the opening includes a plurality of openings spaced apart from one another, the protrusion includes a plurality of protrusions, each including a head and a connecting member coupled to the head and extending through a respective one of the plurality of openings, the head of a first protrusion of the plurality of protrusions contacts a first battery cell of the adjacent battery cells, and the head of a second protrusion of the plurality of protrusions contacts a second battery cell of the adjacent battery cells, and a connecting member of the first protrusion contacts the second battery cell, and a connecting member of the second protrusion contacts the first battery cell.

The elastomer may include at least one material selected from the group consisting of rubber, silicon, and polystyrene.

The elastomer may have a hardness of about 30 Hs to about 100 Hs according to the Korean Standard KS B 0807 (“METHOD OF SHORE HARDNESS TEST”).

In one embodiment, a battery module further includes a housing containing the plurality of battery cells and the barrier, the housing including a first end plate at a first end of the battery module and contacting an outer surface of an outermost battery cell of the plurality of battery cells at the first end; a second end plate at a second end of the battery module and contacting an outer surface of an outermost battery cell of the plurality of battery cells at the second end; and at least one connection plate connecting the first end plate and the second end plate.

In one embodiment, the barrier further includes another protrusion, the another protrusion including a material different than the elastomer.

According to another embodiment of the present invention, a battery module includes a plurality of battery cells arranged in one direction, a barrier disposed between the plurality of battery cells; and a housing accommodating the battery cells and the barrier, wherein the barrier includes a plate including at least one opening and a protrusion formed to pass through the opening, and at least part of the protrusion is formed of an elastomer.

The opening may include a plurality of holes formed in the plate at regular intervals.

The plate may include a first side and a second side, and the protrusion may include a first head or a second head formed in the first side or the second side. Here, the protrusion may further include a connecting member connecting the first head to the second head and being formed to pass through the opening of the plate.

Further, the first head or the second head may have a round or polygonal tube shape.

Here, the first heads or the second heads may be formed at regular intervals.

One of the first head, the second head, and the connecting member may be formed of an elastomer.

Further, the first head and the connecting member may be formed of an elastomer and be integrated.

A plurality of rows of the first heads or a plurality of rows of the second heads may be arranged in lines on the first side or the second side of the plate, and the rows of the first heads and the rows of the second heads may be alternately arranged on the same side.

The first head and the second head may be connected by the connecting member and be integrated.

The connecting member may be formed to have a size corresponding to that of the opening of the plate.

The connecting member may include a spring.

The elastomer may include one of rubber, silicon, and polystyrene.

The elastomer may have a hardness of 30 Hs to 200 Hs.

The housing may include a pair of first and second end plates disposed outside the battery cells, and a side plate and a bottom plate connecting the first and second end plates.

According to another embodiment of the present invention, a barrier for separating battery cells of a battery module includes a plate, and a protrusion extending from the plate in a first direction and contactable with the battery cells, the protrusion including an elastomer. In one embodiment, the plate has an opening formed therethrough in the first direction, and the protrusion extends through the opening. The protrusion may include a first head contacting a first battery cell of the battery cells, and a connecting member coupled to the first head and extending through the opening. The protrusion may further include a second head coupled to an end of the connecting member opposite the first head, the second head contacting a second battery cell of the battery cells. The connecting member may include a spring. The elastomer may include at least one material selected from the group consisting of rubber, silicon, and polystyrene.

According to an aspect of embodiments of the present invention, a battery module uses a novel barrier, such that the battery module effectively cools battery cells and is light.

Further, according to other aspects of embodiments of the present invention, a battery module effectively prevents or reduces swelling of battery cells to improve reliability of the battery cells and enhances production efficiency.

DETAILED DESCRIPTION

Referring toFIGS. 1 to 3D, an exemplary embodiment of the present invention is described.

FIG. 1is a perspective view of a battery module according to an exemplary embodiment of the present invention, andFIG. 2is an exploded perspective view of the battery module ofFIG. 1.

Referring toFIGS. 1 and 2, a battery module100according to an embodiment of the present invention includes a plurality of battery cells10arranged in one direction; a barrier150adisposed between the plurality of battery cells10(e.g., between adjacent battery cells10of the plurality of battery cells10); and a housing110,120,130, and140accommodating the battery cells10and the barrier150a. The barrier150aincludes a plate151having at least one opening151a, and a protrusion152formed to pass through the opening, wherein at least part of the protrusion152includes an elastomer.

The battery cells10may be formed by accommodating an electrode assembly and an electrolyte in a battery case and sealing the battery case with a cap assembly14. The cap assembly14may include a positive terminal11and a negative terminal12which are formed on opposite end portions of the cap assembly14and a vent13formed between the positive and negative terminals11and12. The electrode assembly, in one embodiment, includes a positive plate, a negative plate, and a separator disposed between the plates. The positive plate is connected to the positive terminal11, and the negative plate is connected to the negative terminal12, so that energy generated by an electrochemical reaction of the electrode assembly and the electrolyte is transmitted to the outside of the battery cell10. Further, the vent13functions as a path through which gas generated in the battery cell10may be discharged to the outside of the battery cell10.

The housing110,120,130, and140fixes the plurality of battery cells10and the barrier150ato form the battery module100. The housing110,120,130, and140may be formed of a pair of first and second end plates110and120disposed at outside ends of the plurality of battery cells10, and at least one side plate130and a bottom plate140connecting the first and second end plates110and120to each other.

In one embodiment, the first and second end plates110and120, a pair of side plates130, and the bottom plate140form a space to accommodate the battery cells10, and the battery cells10are arranged in one direction within the housing110,120,130, and140. In one embodiment, the battery cells10are arranged side by side with wide front sides facing each other. In one embodiment, the positive terminal11or the negative terminal12of two neighboring battery cells10are electrically connected through a bus bar15. The bus bar15includes a pair of holes through which the positive terminal11and the negative terminal12pass, and the bus bar15with the positive terminal11and the negative terminal12passing through the holes to be connected may be fixed by a nut16or the like.

In one embodiment, the pair of side plates130supports opposite lateral sides of the battery cells10, and the bottom plate140supports a bottom side of the battery cells10. End portions of the side plates130and the bottom plate may be respectively coupled with the first end plate110, and opposite end portions thereof may be coupled with the second end plate120, so that the first and second end plates110and120are connected to each other. Coupling may be made using a bolt and a nut, for example, but is not limited thereto.

The first and second end plates110and120, in one embodiment, are disposed to be in surface contact with battery cells10disposed at opposite ends to press the plurality of battery cells10together. In one embodiment, the battery cells10supported by the first and second end plates110and120are arranged with the positive terminals11and the negative terminals12being alternately disposed, so that neighboring terminals are connected in series.

The housing110,120,130, and140formed of the first and second end plates110and120, the pair of side plates130, and the bottom plate140is provided to stably fix the battery cells10and may be modified variously, and is not limited to the above-described configuration. Further, a connection structure and a number of battery cells10may be varied based on a design of the battery module100.

FIG. 3Ais a perspective view of a barrier according to an embodiment of the present invention;FIG. 3Bis an exploded perspective view of the barrier ofFIG. 3A;FIG. 3Cis a cross-sectional view taken along a line A-A ofFIG. 3A; andFIG. 3Dis an exploded cross-sectional view ofFIG. 3C.

Referring toFIGS. 3A to 3D, the barrier150adisposed between the plurality of battery cells10may include the plate151having the at least one opening151a, and the protrusion152formed to pass through the opening151a. At least part of the protrusion152includes an elastomer.

The barrier150ais disposed between two neighboring battery cells10to space the battery cells10from each other. Thus, a space may be formed between the battery cells10due to the barrier150a. The space may function as a path to discharge heat therethrough so that heat generated in the battery cells10due to charging and discharging is not accumulated. Further, the space may be a path of a heat transmission medium for cooling or heating of the battery cells10.

In one embodiment, a plurality of the openings151amay be formed at regular intervals. The plate151includes a first side151band a second side151c. The protrusion152may include a first head152aor a second head152bformed on the first side151bor the second side151c. Further, the protrusion152may further include a connecting member152cconnecting the first head152aand the second head152band formed to pass through the opening151a.

The first head152aor the second head152bmay have a round or polygonal tube shape, and the first heads152aor the second heads152may be formed on the plate151at regular intervals. However, the present invention is not limited thereto and, in other embodiments, the protrusions152may have any other suitable shapes and spacing from one another.

Generally, the battery cells10use a structure of pressing the battery cells10at a predetermined pressure or greater in order to control swelling of the battery cells10occurring due to charging and discharging processes. Further, neighboring battery cells10are spaced such that the battery cells10may be heated or heat may be discharged from the battery cells10. Thus, the barrier150ahaving an approximately corresponding size to the battery cells10is disposed between the battery cells10. In one embodiment, the barrier150aincludes the protrusion152and the plate151supporting the protrusion152. Further, the barrier150amay be disposed so that the protrusion152is in direct contact with the battery cells10.

When the battery module100is formed, an insulating process may be applied to at least one of the battery cells10and the protrusion152to prevent or substantially prevent a short circuit from occurring therebetween. In one embodiment, the insulating process may be achieved by providing tubing on a surface of the battery cells10using a nonconductive material or an insulating film. However, the tubing formed on the external surface of the battery cells10may be broken by external impact or may be damaged by friction between the protrusion152and the battery cell10due to vibrations in the battery module100. When the tubing is damaged, the battery cells10may electrically short-circuit with the outside, and an external appearance of the battery cells10may become deformed.

The barrier150aincludes the protrusion152, a part being in direct contact with the battery cells10, at least part of which may be formed of an elastomer. Generally, the elastomer is a material which may be restored from deformation by external force and has excellent anti-attrition, elongation, and impact strength.

At least one of the first head152a, the second head152b, and the connecting member152cof the protrusion152may be formed of an elastomer. In one embodiment, the first head152aand the connecting member152cmay be formed of an elastomer, and may be integrally formed or formed separately.

In one embodiment, when the first head152aand the connecting member152care integrated, the connecting member152cpasses through the opening151aso that the first head152ais disposed on the first side151bof the plate151, and then the second head152bis coupled with the connecting member152cpassing through the opening151aon the second side151cof the plate151, thus manufacturing the barrier150a.

In one embodiment, the connecting member152cmay have a corresponding shape to the opening151aof the plate151. The connecting member152c, in one embodiment, connects and fixes the first head152aand the second head152bdisposed on the first side151band the second side151cof the barrier150a, respectively, the connecting member152cpassing through the opening151aof the plate151. The connecting member152cmay have a size at least long enough to pass through the opening151a, but, in one embodiment, has a corresponding size to the opening151ain order to stably fix the first head152aand the second head152band to improve anti-vibration in the battery module100.

In one embodiment, an end portion of the connecting member152cwhich is not connected to the first head152aand a portion of the second head152bcorresponding to the end portion of the connecting member152cmay each further include a coupling part. The coupling parts may be provided to couple and fix the connecting member152cand the second head152b, and the coupling part provided on the end portion of the connecting member152cmay be correspondingly coupled with the coupling part provided on the second head152b. For example, the coupling parts may include a groove-protrusion combination, a hook combination, a screw combination, or the like, or any other suitable coupling device.

The elastomer forming at least part of the protrusion152may have a hardness of 30 Hs to 100 Hs. The elastomer may include, for example, at least one of rubber, silicon, and polystyrene. When the hardness of the elastomer is less than 30 Hs, the elastomer has inferior durability, so that the elastomer part of the protrusion152may be easily worn out or damaged. When the hardness of the elastomer is more than 100 Hs, the protrusion152has an inflexible structure, such that anti-vibration is not sufficiently effective and the tubing of the battery cells10may be damaged by external force or vibrations to cause a short circuit.

Hereinafter, other exemplary embodiments of the barrier of the present invention are described with reference toFIGS. 4A to 9C. Except as described below, configurations and aspects of the barriers of the embodiments ofFIGS. 4A to 9Care similar to the barrier150adescribed above with reference toFIGS. 1 to 3D, and, therefore, are not repeated.

FIG. 4Ais a perspective view of a barrier according to another embodiment of the present invention, andFIG. 4Bis a cross-sectional view taken along a line A′-A′ ofFIG. 4A.

Referring toFIGS. 4A and 4B, a barrier150bmay include the plate151having at least one opening151aand a protrusion152′ formed to pass through the opening151a. At least part of the protrusion152′ is formed of an elastomer. The protrusion152′ includes the first head152aformed on the first side151bor the second side151cof the plate151. Further, the protrusion152′ includes the connecting member152cpassing through the opening151aand being integrated with the first head152a.

In the protrusion152′, only the first head152ais formed on the first side151bof the plate151, but a second head is not present on the second side151cof the plate151. In one embodiment, an end portion of the connecting member152cof the protrusion152′ is exposed on the second side151c. Thus, battery cells facing the second side151care spaced by the exposed end portion of the connecting member152c, such that a space between the battery cells is formed. The connecting member152cmay be integrated with the first head152a, and a process of forming a second head, as described above, is omitted, and thus the protrusion152′ may be formed via a single process, improving processing efficiency. The connecting member152cmay be fixed by friction between the connecting member152cand the opening151aof the plate151without a second head.

FIG. 5Ais a perspective view of one side of a barrier according to another exemplary embodiment of the present invention;FIG. 5Bis a perspective view of another side of the barrier ofFIG. 5A;FIG. 5Cis a cross-sectional view taken along a line B-B ofFIG. 5C; andFIG. 5Dis an exploded cross-sectional view ofFIG. 5C.

Referring toFIGS. 5A to 5D, a barrier250aaccording to one embodiment includes a plate251having at least one opening251aand a protrusion252formed to pass through the opening251a. At least part of the protrusion252is formed of an elastomer.

The plate251includes a first side251band a second side251c, and the protrusion252may include a first head252aor a second head252bformed on the first side251bor the second side251c. Further, the protrusion252may further include a connecting member252cconnecting the first head252aand the second head252band may be integrated with the first head252a. A plurality of the first heads252aor the second heads252bmay be arranged in one or more lines (e.g., rows or columns) on the first side251bor the second side251cof the plate251, and, in one embodiment, lines of the first heads252aand lines of the second heads252bmay be alternately arranged on the same side.

In one embodiment, the first head252aand the second head252bmay be formed of different materials. For example, the first head252aand the second head252bmay be formed of different elastomers, or at least one of the first head252aand the second head252bmay be formed an elastomer and the other of the first head252aand the second head252bmay be formed of a different material. The connecting member252cmay also be formed of a different material from at least one of the first head252aor the second head252b. In one embodiment, the connecting member252cis integrated with the first head252aand includes the same material as the first head252a.

The first head252aintegrated with the connecting member252cmay be formed on the first side251bor the second side251cof the plate251to pass through the opening251a. The connecting member252cpassing through the opening251amay be coupled with the second head252bon the second side251cor the first side251b. In one embodiment, the first heads252aare formed on both the first side251band the second side251c, and one or more of the first heads252aarranged in a line and one or more of the second heads252barranged in a line may be alternately disposed on the first side251b. However, the present invention is not limited to the first heads252aand the second heads252bbeing arranged in lines and, in other embodiments, the first heads252aand the second heads252bmay be arranged in any other suitable pattern.

The coupling may be performed by a groove-protrusion combination, a hook combination, a screw combination, or the like. Here, materials or arrangements of the first heads252aand the second heads252bmay be modified based on a design of the battery module, for example, such as a channel of a refrigerant, anti-vibration of the battery cells, or the like.

FIG. 6Ais a perspective view of a barrier according to another exemplary embodiment of the present invention, andFIG. 6Bis a cross-sectional view taken along a line B′-B′ ofFIG. 6A.

Referring toFIGS. 6A and 6B, a barrier250baccording to one embodiment includes the plate251having the at least one opening251aand a protrusion252′ formed to pass through the opening251a. At least part of the protrusion252′ is formed of an elastomer.

The plate251includes the first side251band the second side251c, and the protrusion252′ includes the first head252aand the connecting member252c. A plurality of first heads252amay be arranged in lines (e.g., rows or columns) on the first side251bor the second side251cof the plate251, and the first heads252amay be omitted in alternating (e.g., even-numbered) lines on one of the first side251bor the second side251cand in alternating (e.g., odd-numbered) lines on the other of the first side251bor the second side251c. In one embodiment, the protrusions252′ may be provided only in odd-numbered rows on the first side251band may be provided only in even-numbered rows on the second side251c, and end portions of the first heads252aand end portions of the connecting members252cmay be alternately arranged in different rows on the first side251bor the second side251c. Also, the present invention is not limited to the first heads252aand the connecting members252cbeing arranged in lines and, in other embodiments, the first heads252aand the connecting members252cmay be arranged in any other suitable pattern.

FIG. 7Ais a perspective view of a barrier according to another exemplary embodiment of the present invention, andFIG. 7Bis a cross-sectional view taken along a line C-C ofFIG. 7A.

Referring toFIGS. 7A and 7B, a barrier350may include a plate351including a first side351b, a second side351c, and at least one opening351aformed to extend from the first side351bto the second side351c. The barrier350may include a protrusion352formed to pass through the opening351a. At least part of the protrusion352is formed of an elastomer.

The protrusion352may include a first head352aand a second head352bformed on the first side351band the second side351cof the plate351, respectively, and a connecting member352cconnecting the first head352ato the second head352b. Further, the connecting member352cmay include a spring.

The connecting member352cis formed to pass through the opening351aof the plate351and connects the first head352ato the second head352bto fix the first head352aand the second head352bon the plate351. In one embodiment, the connecting member352cincludes a spring to be used regardless of a change in a thickness of the plate351. That is, the connecting member352cincludes a spring having superior elasticity to be free from limitations in a size of the barrier350, and may reduce defects due to assembly tolerances.

FIG. 8Ais a perspective view of a barrier according to another exemplary embodiment of the present invention;FIG. 8Bis a cross-sectional view taken along a line D-D ofFIG. 8A; andFIG. 8Cis an exploded cross-sectional view ofFIG. 8B.

Referring toFIGS. 8A to 8C, a barrier450includes a plate451including a first side451b, a second side451c, and at least one opening451aformed to extend from the first side451bto the second side451c. The barrier450includes a protrusion452formed to pass through the opening451a. At least part of the protrusion452is formed of an elastomer.

The protrusion452may include a pair of a first head452aand a second head452b, and a connecting member452cconnecting the first head452ato the second head452b. In one embodiment, the first head452a, the second head452b, and the connecting member452cmay be integrally formed.

In one embodiment, the protrusion452includes an elastomer, and thus an external shape thereof may be easily transformed by an external force. Thus, the protrusion452in which the first head452a, the second head452b, and the connecting member452care integrated may pass through the opening451aon the first side451bor the second side451cof the plate451.

Further, at least one of the first head451bor the second side451cmay have a tapering cross-sectional shape to easily pass through the opening451a. That is, an end portion of the first head452aor the second head452bwhich is not connected to the connecting member452chas a smaller diameter or an approximately same diameter as the opening451ato easily pass through the opening451a. Further, another end portion of the first head452aor the second head452bwhich is connected to the connecting member452chas a larger diameter than the opening451ato be fixed on an outer side of the opening451a, such that the protrusion452is not separated from the plate451after passing through the opening451a. That is, the other end portion of the first head452aor the second head452bwhich is formed to be larger than the opening451aabuts the plate451at an entrance of the opening451a, such that the protrusion452may be stably fixed to the plate451.

FIG. 9Ais a perspective view of a barrier according to another exemplary embodiment of the present invention;FIG. 9Bis a cross-sectional view taken along a line E-E ofFIG. 9A; andFIG. 9Cis an exploded perspective view ofFIG. 9B.

Referring toFIGS. 9A to 9C, a barrier550according to one embodiment includes a plate551having at least one opening551aformed between a first side551band a second side551c, and a protrusion552formed to pass through the opening551a. At least part of the protrusion552is formed of an elastomer.

In one embodiment, the protrusion552includes a first head552aand a connecting member552cconnected to the first head552a. The connecting member552cmay be integrated with the first head552aor may be formed separately.

The connecting member552cmay have a length that is approximately half of a length of the opening551aor less. Further, protrusions552formed of the first head552aand the connecting member552care provided both on the first side551band the second side551cof the plate551, and connecting members552cin the opening551aon each of the first side551band the second side551cface each other in the opening551a. Thus, the same protrusions552may be used to decrease manufacturing costs of the battery module, reducing production costs.