Battery cover insulator system for fluid communication with battery vents

A battery module is provided that includes a plurality of battery cells. Each battery cell can include a vent. A cover encloses the vents, and an insulation member is located between the plurality of battery cells and the cover. The insulation member can include a bent part that sealably engages the cover. The plurality of battery cells can be arranged in a first direction such that the vent of each battery cell is aligned with the vent of an adjacent battery cell. The cover and the insulating member can extend in the first direction to enclose the vents.

BACKGROUND

Exemplary embodiments relate to a battery module including a plurality of battery cells.

2. Description of the Related Art

In a high-output battery module using a non-aqueous electrolyte with a high energy density, a plurality of battery cells are connected in series to constitute a high-capacity battery module for apparatuses requiring high power, e.g., for a motor of an electric car.

A battery cell includes an electrolyte and an electrode assembly formed of a positive plate and a negative plate and generates energy by electrochemical reaction between the plates and the electrolyte. Gas may be generated in the battery cells due to side reactions of the electrochemical reaction.

SUMMARY

According to an embodiment, there is provided a battery module, including a plurality of battery cells, each battery cell including a vent, a cover enclosing the vent, and an insulation member between the battery cell and the cover, wherein the insulation member includes a bent part that sealably engages the cover.

The may cover sealably engage the insulation member to form a gas-tight space between the cover and the battery cell.

The cover may include a body part and an accommodating part, the accommodating part accommodating the bent part.

The bent part may be accommodated by press-fit engagement between the accommodating part and a sidewall of the body part.

The cover may include at least one rib extending from an inward-facing side of the body part.

The rib may include a contact part that presses the insulation member and a non-contact part that does not contact the insulation member.

The insulation member may be a heat resistant, elastic material.

According to an embodiment, there is provided a battery module, including a plurality of battery cells, each battery cell including a vent, a cover enclosing the vent, and an insulation member between the battery cell and the cover, wherein the battery cells are arranged in a first direction such that the vent of each battery cell is aligned with the vent of an adjacent battery cell to provide a plurality of vents aligned in the first direction, the cover and the insulating member extend in the first direction to enclose the vents, and the insulation member includes a bent part sealably engaging the cover.

The insulation member may be a single body extending between adjacent ones of the battery cells.

The insulation member may include openings, each of the openings corresponding to one of the vents.

The vents may be disposed in cap plates of the battery cells. The insulation member may contact the cap plates in sealing engagement therewith.

The bent part may extend in a second direction away from the cap plates, the second direction being perpendicular to the first direction.

The cover may include a gas outlet at one end thereof.

The bent part may extend in the first direction. The cover may include a body part and an accommodating part, the body part and the accommodating part extending in the first direction, the accommodating part accommodating the bent part by press-fit engagement with the accommodating part.

The accommodating part may be on an inside or an outside of the cover along the first direction.

The cover and the insulation member may be a pre-assembled unit.

The cover may include at least one rib extending inwardly toward the battery cells from an inward-facing side of the body part and extending in the first direction.

The rib may include a contact part that presses the insulation member and a non-contact part that does not contact the insulation member.

The non-contact part may correspond to the openings of the insulation member.

DETAILED DESCRIPTION

FIG. 1is a perspective view of a battery module according to one exemplary embodiment,FIG. 2is an exploded perspective view of the battery module ofFIG. 1,FIG. 3Ais an enlarged perspective view of a cover ofFIG. 1,FIG. 3Bis a perspective view of the cover ofFIG. 1which is turned,FIG. 4Ais a cross-sectional view taken along line A-A′ ofFIG. 1, andFIG. 4Bis an enlarged view of a portion B ofFIG. 4A.

Referring toFIGS. 1 to 3A, the battery module100according to the present embodiment includes a plurality of battery cells10, each battery cell10including a vent13. The battery cells10may be arranged in one direction. A cover120encloses the vent13. The cover may include a body part121, and an accommodating part125formed on at least a portion of the body part121. An insulation member130is disposed between the battery cell10and the cover120. The insulating member130may correspond to the vent13and may include a bent part135accommodated in the accommodating part125.

The accommodating part125may be formed on an outside of the cover120along a lengthwise direction of the cover120, and the bent part135of the insulation member130may be accommodated in the accommodating part125. The bent part135of the insulation member130may be formed by bending part of the insulation member130in a z-axis direction. In the present embodiment, the accommodating part125is formed on the outside of the cover120, but embodiments are not limited thereto. For example, the accommodating part125may be formed inside the cover120.

The insulation member130may be formed of at least one material selected from rubber, silicone, and an elastic material. The bent part135of the insulation member130may be forcibly inserted and closely fit into the accommodating part125of the cover120and accommodated in the accommodating part125, affording no space. The bent part135may be accommodated by press-fit engagement between the accommodating part125and a sidewall of the body part121. Accordingly, gas tightness of the insulation member130and the cover120may be secured to prevent gas discharged from the battery cells10from leaking to the outside, and a gas-tight space is formed between the cover and the battery cell. Further, the insulation member130and the cover120may be assembled in advance. Accordingly, an assembly process of the battery module100may be simplified. In detail, alignment of the vent13of the battery cells10and the insulation member130may be facilitated, thereby improving assembly efficiency of the battery module100.

Referring toFIGS. 2 to 4B, the body part121of the cover120may have a hexahedral shape, an inward side of which is open in one direction, and is seated on the battery cells10such that the open side of the body part121faces the vent13. The body part121of the cover120may include an outlet127for gas at one end and the body part121may be closely in contact with the insulation member130to form a gas passage connected to the outlet127.

At least one rib129may be formed on the open inward side of the body part121of the cover120. The rib129may be formed in a lengthwise direction of the body part121and may include a contact part129ain contact with the insulation member130and the non-contact part129bthat provides an opening corresponding to the vent13. The cover120may have a shape nearly corresponding to the insulation member130.

When the rib129is formed on the open inward side of the body part121of the cover120, gas tightness of the cover120and the insulation member130is further improved. In detail, the non-contact part129bof the rib129may be formed corresponding to an opening131of the insulation member130, and the contact part129amay be in contact with the insulation member130between the openings131to press the insulation member130. That is, the non-contact part129bof the rib129does not disturb gas discharge from the opening131of the insulation member130corresponding to the vent13, and the contact part129aof the rib129is in contact with the insulation member130between the openings131while pressing the insulation member130, thereby improving gas tightness of the cover120and the insulation member130.

The insulation member130is disposed between the cover120and the battery cells10. The vents13of the battery cells10may include cap plates, and the insulation member130may contact he cap plates in sealing engagement therewith. The bent part135of the insulation member130may be accommodated in the accommodating part125of the cover120, and the remaining portion of the insulation member130other than the bent part135may be in contact with the contact part129aof the rib129, being pressed thereby. The cover120covering the insulation member130may be in close contact with the insulation member130to maintain gas tightness of the gas passage. Further, the insulation member130may further include the opening131corresponding to the vent13of the battery cells10, and the rib129may include the non-contact part129bthat is open corresponding to the vent13. Accordingly, gas discharge from the battery cells10is not disturbed.

According to the present embodiment, gas tightness of the insulation member130and the cover120may be secured, thereby preventing gas discharged from the battery cells10from leaking to the outside. Further, the insulation member130and the cover120may be assembled in advance. The assembly process of the battery module100may be simplified. In detail, alignment of the vent13of the battery cells10and the insulation member130may be facilitated to improve the assembly efficiency of the battery module100.

The battery cells10may generate gas due to byproducts of electrode plates and an electrolyte with repeated charge and discharge, and such gas may be discharged through the vent13. The gas may be discharged to the outside through the outlet127formed in the cover120. The outlet127may have a T shape, left and right sides of which are open so that the gas does not affect neighboring battery modules100, but is not limited thereto.

The insulation member130may be formed in a single body. Battery cells typically generate heat with repeated charge and discharge. The plurality of battery cells10may emit high-temperature heat sufficient to melt an insulation member that is mounted on the battery cells10and that is not formed of a heat resistant material. If the insulation member130were to melt, sealing efficiency between the insulation member130and the cover120could be reduced, so that gas could leak. Accordingly, the insulation member130may be a gasket formed of a heat resistant material to prevent gas leakage.

An exterior case of the battery cells10may be formed of metal, and the cover120may be formed of a plastic resin. Here, if the battery cells10and the cover120were to be in direct contact with each other, contact would not be easy due to the difference in the materials of the battery cells10and the cover120, and thus gas could leak in an insecure contact part. The insulation member130may serve as a gasket between the battery cells10and the cover120to conveniently maintain gas tightness between the battery cells10and the cover120.

The insulation member130formed in the single body may seal a plurality of vents13of the battery cells10at the same time. The insulation member130may include a plurality of openings131corresponding to the vents13.

Each of the battery cells10may include a battery case having an open part and a cap plate14covering the open part. The battery case may accommodate an electrolyte and an electrode assembly formed of a positive plate, a negative plate, and a separator disposed between the plates. The cap plate14may include a positive electrode11connected to the positive plate and a negative electrode12connected to the negative plate, the electrodes being at opposite end portions and protruding to the outside. The positive plate and the negative plate constituting the electrode assembly may react with the electrolyte to generate energy, which may be transmitted to the outside through the positive electrode11and the negative electrode12.

Further, the vent13may be disposed between the positive electrode11and the negative electrode12of the cap plate14to serve as a passage for gas to be discharged from the battery cells10when pressure of gas generated in the battery cells10is equal to or greater than a predetermined level. Thus, the vent13may prevent damage of the battery cells10due to internal pressure.

In the present embodiment, the battery cells10may be arranged in one direction. The battery cells10may be arranged parallel to each other, with wider front sides facing each other. The vents13may be positioned in a center portion of the battery cells10and disposed in a nearly straight line along the arranged battery cells10. The positive electrodes11and the negative electrodes12of two neighboring battery cells10may be electrically connected to each other through a metal bus-bar (not shown).

A housing110may include a pair of end plates111spatially spaced from each other in one direction and a plurality of connecting members connecting the end plates111. The connecting members may include a side bracket112connecting lateral sides of the end plates111and a bottom bracket113connecting bottom sides of the end plates111. The plurality of battery cells10may be accommodated between the end plates111.

The end plates111may be disposed to be in surface contact with outermost battery cells10, respectively, and press the plurality of battery cells10inwardly. Further, the side bracket112may be connected to one end portion and the other end portion of the end plates111to support opposite lateral sides of the battery cells10. Bottom sides of the battery cells10may be supported by the bottom bracket113, and opposite end portions of the bottom bracket113may be connected to the end plates111.

The plurality of battery cells10, supported by the end plates111, the side bracket112, and the bottom bracket113, may be arranged therein with the positive electrodes11and the negative electrodes12being disposed alternately and connected in series using bus-bars. A connection structure and the number of battery cells10may be changed variously depending on a design of the battery module100.

A barrier115may be interposed between neighboring battery cells10. A spacer (not shown) may be provided to the barrier115so as to space apart the neighboring battery cells10from each other and to form a space between the battery cells10.

By way of summation and review, a battery module may have a gas passage or outlet to efficiently deal with gas generated in a plurality of battery cells. According to one exemplary embodiment, there is provided a battery module which secures tightness of gas generated in a plurality of battery cells due to a simplified working process, thereby preventing gas discharged from the battery cells from leaking to the outside.

Further, the battery module may have a simplified assembly process. An insulation member and a cover may be assembled in advance.

In addition, alignment of a vent and the insulation member may be facilitated.

Assembly efficiency of the battery module may be improved.

In the present embodiment, a polygonal lithium ion secondary battery may be illustrated as an example of the battery cell, but embodiments are not limited thereto. Various types of batteries, such as a lithium polymer battery, or various shapes, such as a cylindrical battery may be used.