CN102214806B - Battery module - Google Patents

Abstract

Battery modules have a plurality of electrode assemblies in which the electrode tabs of electrode assemblies are easily attached to the battery cases by a common insulator including receptacles for receiving the electrode assemblies. These configurations enable easy manufacture of medium- and large-sized battery modules with a plurality of electrode assemblies. In some embodiments, a battery module includes an insulator capable of mounting a plurality of electrode assemblies and receptacles in the insulator for receiving a portion of each electrode assembly.

Description

battery unit

technical field

The present invention relates to a battery cell, and more particularly, to a battery cell including a plurality of electrode assemblies in which electrode tabs of the electrode assemblies can be easily attached to a battery case, thereby manufacturing medium-sized and large-sized battery modules.

Background technique

Unlike primary batteries, which cannot be repeatedly charged, secondary batteries can be repeatedly charged and discharged. Low-capacity secondary batteries with one cell are used in small, portable electronic devices such as cell phones, notebook computers, and camcorders. A high-capacity secondary battery including a plurality of battery cells connected in groups has attracted attention as a power source for driving a motor such as a hybrid electric car or the like.

High-capacity secondary batteries connected in series with each other to drive a motor (for example, an electric vehicle, etc.) require high power and can be used as a battery module. Therefore, high-capacity batteries have been actively researched.

However, when a module including a plurality of small batteries is used as a high-capacity secondary battery, weight and cost increase. Furthermore, in high-capacity secondary batteries, the capacity per unit cell increases, which significantly impairs battery stability and increases the cost required to obtain the same level of performance.

Contents of the invention

Embodiments of the present invention include a secondary battery having a plurality of electrode assemblies, wherein electrode tabs of the electrode assemblies are easily welded (or otherwise attached) to a battery case. The secondary battery includes an insulator having a receiving portion for receiving a part of each electrode assembly. Such a configuration makes it possible to easily manufacture a medium-sized or large-sized battery module.

According to an embodiment of the present invention, a secondary battery includes an insulator for installing a plurality of electrode assemblies in a battery case (eg, a can) and an accommodation part for supporting a portion of each electrode assembly.

The electrode assembly may be a jelly-roll type electrode assembly, and may be circular or flat cylindrical in shape.

In some embodiments, the receiving portions protrude from the upper portion of the insulator, and may be generally cup-shaped such that each receiving portion has an inner cavity for receiving the electrode assembly.

In some alternative embodiments, the receptacle may be a depression in the upper surface of the insulator.

When the receiving part protrudes from the upper part of the insulator, the receiving part may be shaped to support the lower part of the electrode assembly.

The battery includes at least one insulator at an upper or lower portion of the electrode assembly. However, according to some embodiments, a battery includes a first insulator at an upper portion of the electrode assembly and a second insulator at a lower portion of the electrode assembly. In an embodiment including first and second insulators at upper and lower portions of the electrode assembly, each of the first and second insulators may be a single body.

In addition, the insulator may have holes through which the electrode tabs of the electrode assembly pass.

According to an embodiment of the present invention, using an inventive insulator having a receiving portion, it is possible to easily manufacture a medium-sized or a large-sized battery module, thereby protecting battery cells with low mechanical strength and preventing deformation of the electrode assembly.

Furthermore, the inventive insulator enables precise positioning of the electrode assembly, increases the accuracy of the battery assembly, simplifies the battery assembly, and increases the structural stability of the battery.

Furthermore, the overall manufacturing cost can be reduced. Also, when an electrode assembly is broken, the remaining electrode assemblies are not broken (ie, only one electrode assembly is broken), thereby improving stability.

Description of drawings

1 is an exploded perspective view of an insulator and a plurality of electrode assemblies according to an embodiment of the present invention;

Figure 2 is a perspective view of the electrode assembly and insulator of Figure 1, wherein the electrode assembly is installed in the insulator;

3 is a perspective view of a plurality of electrode assemblies installed in first and second insulators according to another embodiment of the present invention;

4 is a perspective view of a secondary battery according to another embodiment of the present invention;

5A is a cross-sectional view taken along line A-A' of FIG. 4, illustrating the connection of the electrode joint and the cover plate according to an embodiment of the present invention;

5B is a cross-sectional view taken along line B-B' of FIG. 4, illustrating the connection of the electrode tab and the battery case according to an embodiment of the present invention;

6 is a cross-sectional view of a secondary battery according to still another embodiment of the present invention;

7 is a perspective view of a plurality of electrode assemblies installed in an insulator according to still another embodiment of the present invention;

8 is a perspective view of a plurality of electrode assemblies installed in an insulator according to still another embodiment of the present invention;

9 is an exploded perspective view of a plurality of electrode assemblies and first and second insulators according to still another embodiment of the present invention.

Detailed ways

Hereinafter, a secondary battery according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is an exploded perspective view of an insulator and a plurality of electrode assemblies (eg, jelly-roll type assemblies) according to an embodiment of the present invention. FIG. 2 is a perspective view of the electrode assembly and the insulator of FIG. 1, wherein the electrode assembly is installed in a receiving portion of the insulator. Referring to FIGS. 1 and 2 , a medium-sized or large-sized secondary battery according to an embodiment of the present invention includes an insulator 20 on which a plurality of electrode assemblies (eg, circular jelly-roll type assemblies) 10 may be disposed. The insulator 20 includes a receiving portion 21 for each electrode assembly, and the receiving portion supports a lower portion of the electrode assembly 10 . In some embodiments, the receiving part 21 protrudes from an upper portion of the insulator 20 and may have an inner cavity into which a lower portion of the electrode assembly 10 is inserted. In addition, the receiving parts 21 are spaced apart at intervals, so that a plurality of electrode assemblies 10 can be arranged at intervals and fixed. The receiving part 21 may protrude from the upper part of the insulator by any suitable length, and the protruding length is not particularly limited, but may extend any length suitable for firmly fixing the electrode assembly 10 .

Each electrode assembly 10 has a first electrode tab 11 extending from an upper portion of the assembly and a second electrode tab 12 extending from a lower portion of the assembly. For convenience, the first electrode joint 11 extending from the upper part is called an anode joint 11 , and the second electrode joint extending from the lower part is called a cathode joint 12 .

A hole 22 for exposing the cathode tab 12 to the outside is formed in the insulator at a position corresponding to the position of the receiving part 21 . By inserting the electrode assembly 10 into the receiving part 21 , the cathode tab 12 is exposed to the outside through the hole 22 of the insulator 20 . The plurality of cathode tabs 12 are exposed through the holes 22 and aligned, and then the plurality of cathode tabs 12 can be easily welded to the battery case (eg, can).

The insulator 20 including the receiving part 21 into which the electrode assembly 10 is installed is inserted into the battery case 32 as shown in FIG. 4 . The cathode tab 12 may be welded (or otherwise attached) to the battery can by inserting the insulator assembly into the battery can, as shown in FIGS. 4 and 5B . The connection of the anode tab 11 and the cathode tab 12 to the cap plate 31 and the battery case 32 , respectively, will be described below with reference to FIGS. 4 to 5B . Also, although FIG. 4 illustrates the first insulator 20a and the second insulator 20b on the upper and lower parts of the electrode assembly, the battery according to an embodiment of the present invention may include only the upper part of the plurality of electrode assemblies 10 or only A single insulator 20 is located at a lower portion of the plurality of electrode assemblies 10 .

There is no limit to the number of accommodation parts of the insulator 20 , and the insulator 20 may accommodate any number of electrode assemblies, for example, two or more electrode assemblies 10 . Furthermore, insulator 20 may be made of any suitable material, such as polypropylene, polyethylene, polyimide, and the like.

The electrode assembly 10 includes an anode plate having an anode active material layer coated on the surface of the anode current collector, a cathode plate having a cathode active material layer coated on the surface of the cathode current collector, and an clapboard. The electrode assembly 10 is wound such that the separator electrically insulates the anode and cathode plates.

The anode plate consists of a thin metal plate with good electrical conductivity. For example, the anode plate may include an anode current collector made of aluminum (Al) foil, and an anode active material layer may be coated on both sides of the foil. Each end of the anode plate includes an anode non-coating region in which the layer of anode active material is not coated on the current collector. One end of the anode non-coating region is joined to the anode tab 11 , and the anode tab 11 is generally made of aluminum (Al) material and protrudes from the upper portion of the electrode assembly 10 by a length.

The cathode plate includes a cathode current collector made of a thin metal plate such as copper (Cu) foil or nickel (Ni) foil, and a layer of cathode active material is coated on both sides of the foil. Each end of the cathode plate includes a cathode uncoated region in which the layer of cathode active material is not coated on the current collector. One end of the cathode non-coating region is joined to a cathode tab 12 , and the cathode tab 12 is generally made of nickel (Ni) material and protrudes from a lower portion of the electrode assembly 10 by a length.

3 is a perspective view of a plurality of electrode assemblies installed in first and second insulators according to another embodiment of the present invention. 4 is a perspective view of a secondary battery according to a second embodiment of the present invention. Referring to FIGS. 3 and 4 , in some embodiments, the insulator 20 may include a first insulator 20 a on upper portions of the plurality of electrode assemblies 10 and a second insulator 20 b on lower portions of the plurality of electrode assemblies 10 . Such a configuration enables easy alignment and positioning of the anode tab 11 protruding from the upper portion of the electrode assembly 10 and the cathode tab 12 protruding from the lower portion of the electrode assembly 10 .

As shown in FIGS. 3 and 4 , the first insulator 20 a includes a first receiving portion 21 a into which upper portions of the plurality of electrode assemblies 10 are inserted. Also, the second insulator 20b includes a second receiving portion 21b into which lower portions of the plurality of electrode assemblies 10 are inserted. The first receiving part 21a and the second receiving part 21b respectively protrude from the first insulator 20a and the second insulator 20b, and each receiving part may have an inner cavity into which its corresponding electrode assembly can be inserted. The first receiving part 21a and the second receiving part 21b may be positioned symmetrically, respectively. That is, the position of the first receiving part 21a on the first insulator 20a may correspond to the position of the second receiving part 21b on the second insulator 20b, as shown in FIGS. 3 and 4 .

The first receiving part 21a receives an upper portion of the electrode assembly 10, and each receiving part 21a includes a first hole 22a for exposing the anode tab 11 to the outside. The second receiving part 21b receives a lower portion of the electrode assembly 10, and each receiving part 21b includes a second hole 22b for exposing the cathode tab 12 to the outside. As a result, the anode tab 11 on the upper portion of the electrode assembly 10 passes through the first hole 22a in the first insulator 20a, and the cathode tab 12 on the lower portion of the electrode assembly 10 passes through the second hole 22b in the second insulator 20b. Then, the insulator assembly (including the plurality of electrode assemblies 10 installed in the first insulator 20a and the second insulator 20b) is inserted into the battery case (eg, can) 32, and the cap plate 31 is placed on the upper part of the insulator assembly to Seal the battery. By inserting the insulator assembly into the battery case 32 and attaching the cover plate 31, the anode tab 11 extending through the first hole 22a is welded (or otherwise attached) to the anode lead 33 formed in the cover plate 31 , the cathode tab 12 extending through the second hole 22 b is welded (or otherwise attached) to the interior of the battery can 32 .

As shown in FIG. 5A , in some embodiments, the anode tab 11 is connected to the cap plate via an anode lead 33 . The cap plate 31 may be insulated from the anode lead 33 via a gasket 34 . In order to connect the anode tab 11 to the anode lead 33, a first hole 22a is provided in the first insulator to correspond in position to the position of the anode lead 33 in the cover plate. This configuration enables easy connection (eg, welding) of the anode tab 11 to the anode lead 33 . Although the battery case 32 and cover plate 31 have been described as having positive polarity, the battery case and cover plate may have opposite polarity.

A plurality of electrode assemblies 10 may be disposed on the insulator such that the anode tab 11 and the cathode tab 12 are precisely positioned at positions where they are attached (eg, welded) to the battery case 32 or the cap plate 31 . That is, the accommodating portions 21a and 21b on the insulators 20a and 20b are positioned so that their corresponding electrode assemblies 10 are precisely located in the battery case 32, so that each of the anode tab 11 and cathode tab 12 can be easily and precisely connected (eg, welded) to the battery case 32 or the cover plate 31. Through such precise positioning of the plurality of electrode assemblies, the battery assembly can be simplified, making it easy to manufacture battery cells and improving the structural stability of the module. In addition, this configuration protects the electrode assembly 10 , which has low mechanical strength, and helps prevent deformation of the electrode assembly 10 .

5A is a cross-sectional view taken along line A-A' of FIG. Referring to FIG. 5A , the anode tab 11 , which protrudes from the upper portion of the electrode assembly 10 installed in the first receiving part 21 a , extends through the first hole 22 a of the first insulator 20 a. The exposed anode tab 11 is welded (or otherwise attached) to the anode lead 33 in a bent configuration so as not to contact the cap plate 31 . The anode lead 33 may be insulated from the cap plate 31 by a gasket 34 . The gasket 34 has generally at its center an insertion hole 35 into which the anode lead 33 can be inserted so that the anode lead 33 can contact the anode tap 11 . As shown in FIG. 5A , the first hole 22 a in the first insulator 20 a guides the position of the anode tab 11 so that the anode lead 33 and the anode tab 11 can be easily connected (eg, welded).

5B is a cross-sectional view taken along line B-B' of FIG. 4 and illustrates the connection of the cathode tab 12 to the battery case 32. Referring to FIG. 5B, the cathode tab 12, which protrudes from the lower portion of the electrode assembly 10 installed in the second receiving part 21b, extends through the second hole 22b of the second insulator 20b. Since the can 32 itself has positive polarity, the cathode tab 12 extending through the second hole 22b is welded (or otherwise attached) to the interior of the can 32 in a bent configuration.

FIG. 6 is a perspective view of a battery module according to still another embodiment of the present invention. Referring to FIG. 6 , the cathode tab 12 is attached to the battery case 32 in the same manner as the battery module in FIG. 4 . However, the attachment of the anode tab 11 to the cover plate is different from FIG. 4 . As shown in Figure 6, the cover plate 31 includes a single anode lead 33' to which the anode tab 11 is attached. The anode tabs 11 protruding from the upper portion of the first insulator 20a are each welded (or otherwise connected) to an electrode lead connection body 36 electrically connected to an insertion hole 35 inserted into a gasket 34' A single anode lead 33'. According to this configuration, the cap plate 31 includes only one anode lead 33', enabling the battery module to have a simpler structure.

A gasket 34' is positioned in the cover plate 31 to insulate the anode lead 33' from the cover plate 31. The cover plate may further include an insulating plate 37 between the electrode lead connection body 36 and the cover plate 31 so that the electrode lead connection body 36 having a negative polarity and the cover plate 31 having a positive polarity can be insulated from each other.

7 is a perspective view of a plurality of electrode assemblies installed in an insulator according to still another embodiment of the present invention. Referring to FIG. 7 , medium-sized and large-sized battery modules may be manufactured using an insulator 20 in which a plurality of electrode assemblies 10 are inserted. The insulator 20 includes a receiving part 21' for supporting lower parts of the plurality of electrode assemblies 10. Referring to FIG. As shown in FIG. 7 , the receiving portion 21' is a depression in the surface of the insulator 20, and the lower portion of the electrode assembly 10 can be inserted into the depression. The recess may have any suitable depth capable of supporting the electrode assembly 10 . For example, the depression may have a depth suitable for surrounding the lower portion of the electrode assembly 10 .

The hole 22 in the insulator through which the cathode tab 12 of the electrode assembly 10 extends is positioned in the housing portion 21 ′ of the insulator such that when the electrode assembly 10 is inserted into the housing portion 21 ′, the cathode tab 12 passes through the insulator 20 The hole 22 extends. Thus, the holes 22 serve to align the plurality of cathode tabs 12, thereby enabling easy attachment (eg by welding) of the tabs 12 to the battery case.

The insulator 20 (having the plurality of electrode assemblies 10 installed in the receiving portion 21') is inserted into the battery case, thus enabling precise positioning of the electrode assemblies 10 within the battery case.

8 is a perspective view of a plurality of electrode assemblies installed in an insulator according to still another embodiment of the present invention. Referring to FIG. 8 , each accommodation portion 21 ″ of the insulator 20 supports at least a portion of the periphery of the lower portion of its corresponding electrode assembly 10. As shown, the accommodation portion 21 ″ protrudes from the upper surface of the insulator 20, and each accommodation portion The portion 21 ″ includes an outer peripheral wall having at least one opening. In other words, the housing portion 21 ″ is configured in any way to obtain a minimum amount of support for the electrode assembly 10 . For example, in one exemplary embodiment, the outer peripheral wall of the receptacle 21" may include more than one opening, and the openings in the wall may repeat at any suitable interval.

FIG. 9 is an exploded perspective view of a plurality of electrode assemblies installed in first and second insulators according to still another embodiment of the present invention. Referring to FIG. 9 , medium-sized and large-sized battery modules can be manufactured by inserting an insulator 20 equipped with a plurality of flat cylindrical electrode assemblies 10 (ie, not a circular assembly) into a battery case (not shown). As shown in FIG. 9 , the insulator 20 includes a first insulator 20 a positioned on the top of the electrode assembly 10 and a second insulator 20 b positioned on the bottom of the electrode assembly 10 . The first receiving part 21a supports the upper portion of the electrode assembly 10 and is formed on the first insulator 20a. The second receiving part 21b supports the lower portion of the electrode assembly 10 and is formed on the second insulator 20b.

As shown in FIG. 9 , the first accommodating portion 21 a and the second accommodating portion 21 b protrude from the first insulator 20 a and the second insulator 20 b, respectively, and are spaced apart to define a position for inserting the electrode assembly 10 . Although housing portions 21a and 21b are shown in FIG. 9 as surrounding the top or bottom of the electrode assembly, housing portions 21a and 21b may have any suitable shape, including any of the shapes discussed above with reference to FIGS. 1-8 . For example, the receiving parts 21a and 21b may be shaped to partially support the top or bottom of the electrode assembly 10, as shown in FIG. 8 .

Since the flat cylindrical electrode assembly 10 has the anode joint 11 and the cathode joint 12 protruding in the same direction, the first insulator 20a includes a first hole 23a and a second hole 23b through which the anode joint 11 extends and the cathode joint 11 extends. The connector extends through this second hole 23b. The first hole 23a and the second hole 23b are respectively formed in the receiving portion 21a of the first insulator 20a at positions corresponding to those of the anode tab 11 and the cathode tab 12, respectively. The anode tab 11 extending through the first hole 23a and the cathode tab 12 extending through the second hole 23b are aligned with where they are attached to the battery case, thereby enabling easy attachment of the tabs (eg by welding) to the shell.

Although the first accommodating portion 21a and the second accommodating portion 21b are illustrated in FIG. 9 as protruding from the first insulator 20a and the second insulator 20b respectively, alternatively, they may be in the first insulator 20a and the second insulator 20b. A depression in the surface, as shown in Figure 7. Also, since the anode tab 11 and the cathode tab 12 protrude from the electrode assembly 10 in the same direction, the insulator may include a single insulator disposed over a portion (eg, an upper portion) of the electrode assembly extending from the tab.

To form the flat cylindrical electrode assembly 10, a separator is positioned between the anode plate and the cathode plate, and the structure is wound to form a jelly-roll type electrode assembly. The anode tab 11 is connected to the anode plate and protrudes from the top of the electrode assembly 10 . A cathode tab 12 is connected to the cathode plate and also protrudes from the top of the electrode assembly 10 . The anode tab 11 and the cathode tab 12 are separated from each other and electrically connected to the electrode assembly 10 . In addition, a lamination tape 13 may be wound around portions where the anode tab 11 and the cathode tab 12 are connected to the electrode assembly 10 . The lamination tape 13 blocks heat generated from the anode tab 11 or the cathode tab 12 and prevents the edge of the anode tab 11 or the cathode tab 12 from pressing the electrode assembly 10 .

Although in the above-described embodiments, holes are formed in the insulator to expose the electrode tabs, through holes for discharging heat generated from the electrode assembly may also be formed.

Although the invention has been illustrated and described with reference to certain exemplary embodiments, it will be understood by those skilled in the art that various modifications and changes may be made to the described embodiments without departing from the spirit and spirit of the invention as defined by the claims. scope.

This application claims priority to U.S. Provisional Application No. 61/323,274, filed April 12, 2010, in the USPTO and U.S. Nonprovisional Application No. 12/916,339, filed October 29, 2010 in the USPTO rights and interests, the entire contents of which are hereby incorporated by reference.

Claims (12)

1. A battery unit, comprising: at least two electrode assemblies, each electrode assembly comprising an anode, a cathode, a separator between the anode and cathode, and an electrode joint extending from either the anode or the cathode; at least one insulating plate having at least one opening through which at least one of the electrode joints passes, and the at least one insulating plate includes a receiving portion for each electrode assembly, each receiving portion being configured to housing at least a portion of its corresponding electrode assembly; and a battery case and a cover plate assembly surrounding the at least one insulating plate and the at least two electrode assemblies, wherein the cover plate assembly includes electrode leads for electrical connection to electrode contacts, Wherein the receiving portion includes an outer wall having at least one opening. 2. The battery cell of claim 1, wherein the insulating plate includes a surface, wherein each receiving portion includes at least one wall protruding beyond the surface. 3. The battery cell according to claim 1, wherein the at least one insulating plate is a first insulating plate and a second insulating plate. 4. The battery cell according to claim 3, wherein each electrode tab of each electrode assembly comprises a first electrode tab extending from a first end of the electrode assembly and a first electrode tab extending from a second end of the electrode assembly. For a second electrode joint, the at least one opening in the at least one insulating plate is a first opening in the first insulating plate and a second opening in the second insulating plate, wherein the first An electrode tab extends through the first opening in the first insulating plate, and the second electrode tab extends through the second opening in the second insulating plate. 5. The battery cell according to claim 4, wherein the first electrode tab of each electrode assembly extends through the first opening in the first insulating plate and contacts the battery case, and each The second electrode tab of the electrode assembly extends through the second opening in the second insulating plate and contacts the cap plate assembly. 6. The battery cell of claim 5, wherein the cover plate assembly further comprises: cover plate, Wherein the electrode leads are a plurality of electrode leads for each electrode assembly, wherein the second electrode joint of each electrode assembly contacts its corresponding electrode lead. 7. The battery cell according to claim 6, wherein the cap plate further comprises a gasket configured to insulate the electrode lead from the cap plate. 8. The battery cell of claim 5, wherein the cover plate assembly further comprises: cover plate; and an electrode lead connection, wherein the second electrode tab of each electrode assembly contacts the electrode lead connection, Wherein the electrode leads are connected to the electrode lead connecting body. 9. The battery cell of claim 8, wherein the cap assembly further comprises an insulator. 10. The battery cell according to claim 1, wherein the electrode tabs of each electrode assembly include a first electrode tab and a second electrode tab each extending from a first end, and the insulating plate includes an electrode tab for each electrode. A first opening and a second opening of the assembly, wherein the first electrode tab extends through the first opening and the second electrode tab extends through the second opening. 11. The battery cell of claim 1, wherein each receiving portion is configured to receive at least a portion of a periphery of the first end of its corresponding electrode assembly. 12. The battery cell according to claim 1, wherein each receiving portion includes a depression in a surface of the insulating plate.