Battery module having holder

An exemplary embodiment of the present invention provides a battery module including a plurality of rechargeable batteries, a holder defining a plurality of storage spaces for holding the rechargeable batteries in a stacked configuration, a housing for enclosing the holder, and including a first cover and a second cover that face each other and press the holder, and a protective circuit module in the housing and configured to control charging and discharging operations of the rechargeable batteries.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to, and the benefit of, Korean Patent Application No. 10-2015-0115556 filed in the Korean Intellectual Property Office on Aug. 17, 2015, the entire contents of which are incorporated herein by reference.

BACKGROUND

Embodiment of the present invention relate to a battery module, and more particularly, to a battery module having a holder.

2. Description of the Related Art

A rechargeable battery differs from a primary battery in that it can be repeatedly charged and discharged, while the latter is incapable of being recharged. Low-capacity rechargeable batteries are used in small portable electronic devices, such as mobile phones, notebook computers, and camcorders, while high-capacity rechargeable batteries are widely used as a power source for driving a motor of an electric or hybrid vehicle.

A large capacity battery module consists of a plurality of rechargeable batteries, and the rechargeable batteries are connected in series or in parallel via a bus bar. The rechargeable batteries are fixed by an end plate, and are inserted into a housing along with a protective circuit module. When a structure for fixing rechargeable batteries is complicated, assembly efficiency of the battery module is reduced. In addition, the protective circuit module should be stably fixed inside the housing, and heat generated in the protective circuit module should be rapidly discharged.

SUMMARY

Embodiments of the present invention provide a battery module that can stably support rechargeable batteries, and a protective circuit module.

A battery module according to an exemplary embodiment of the present invention includes a plurality of rechargeable batteries, a holder defining a plurality of storage spaces for holding the rechargeable batteries in a stacked configuration, a housing for enclosing the holder, and including a first cover and a second cover that face each other and press the holder, and a protective circuit module in the housing and configured to control charging and discharging operations of the rechargeable batteries.

The battery module may further include a protection wall and a converter, and the housing may define a battery region into which the holder is inserted, and a circuit region into which the protective circuit module and the converter are inserted, and the battery region and the circuit region may be partitioned by the protection wall.

An upper end of the protection wall may be separated from a top surface of the second cover.

The holder may be cuboid shaped, and may include a plurality of barriers for defining the storage spaces.

The battery module may further include two support bars fixed at a side of the holder, and extending in a stacking direction of the rechargeable batteries, the support bars respectively defining terminal holes for respectively accommodating terminals of the rechargeable batteries.

The battery module may further include a bus bar for electrically coupling the terminals, and one of the support bars may include support protrusions for contacting lateral sides of the bus bar to support the bus bar.

The battery module may further include a first buffer plate having elasticity between the first cover and the protective circuit module.

The battery module may further include a first support protruding from the first cover to contact the first buffer plate.

The battery module may further include a second buffer plate having elasticity between the second cover and the converter.

The battery module may further include a second support protruding from the second cover to contact the second buffer plate.

The first buffer plate and the second buffer plate may include a thermally conductive polymer or a thermally conductive silicon.

The battery module may further include a first support protruding from the first cover, and a first thermally conductive plate between the protective circuit module and the first support.

The battery module may further include an upper thermal grease layer between the first thermally conductive plate and the first support.

The battery module may further include a second support protruding from the second cover to support a bottom surface of the converter, and a second thermally conductive plate between the converter and the second support.

The battery module may further include a lower thermal grease layer between the second thermally conductive plate and the second support.

The first thermally conductive plate and the second thermally conductive plate may include an elastic polymer plated with a thin metal layer.

According to embodiments of the present invention, the rechargeable batteries and the protective circuit module can be stably supported using the holder and the housing.

DETAILED DESCRIPTION

FIG. 1is a perspective view of a battery module according to a first exemplary embodiment of the present invention, andFIG. 2is a cross-sectional view of the battery module ofFIG. 1taken along the line II-II.

Referring toFIGS. 1 and 2, the battery module101according to the current first exemplary embodiment includes a plurality of rechargeable batteries30, a holder20, a housing10, a protective circuit module42(seeFIG. 5), and a converter41(seeFIG. 5).

The rechargeable batteries30of embodiments of the present invention may substantially have a prismatic shape, and the rechargeable batteries30according to the current exemplary embodiment each have a quadrangular pillar shape. The rechargeable battery30performs charging and discharging operations, and may be a lithium-ion battery or a lithium polymer battery. A positive electrode terminal31and a negative electrode terminal32(seeFIG. 3) are formed to protrude outside of each of the rechargeable batteries30.

The housing10encloses the holder20, and includes an upper first cover12and a lower second cover13. The first cover12includes a receiving unit121that is concavely depressed to define an internal space, and a flange portion123that outwardly extends from a lower end of the receiving unit121. The receiving unit121is formed to have a rectangular cross-section, and accommodates the rechargeable batteries30, the protective circuit module42, and the converter41therein.

A vent member15that is configured to be ruptured at a predetermined pressure is provided in the receiving unit121, and a notch15ais formed in the vent member15(e.g., the vent member15is scored to be configured to rupture). The flange portion123of the first cover12is fixed to the second cover13by a bolt16and a nut17while contacting the second cover13.

FIG. 3is a partially exploded perspective view of the holder and the rechargeable batteries according to the first exemplary embodiment of the present invention, andFIG. 4is a cut-away perspective view of the holder according to the first exemplary embodiment of the present invention.

Referring toFIGS. 3 and 4, a plurality of storage spaces23into which the rechargeable batteries30are inserted are formed in the holder20, and the storage spaces23are partitioned by barriers21(e.g., barriers21of the holder20). The barriers21are interposed between the rechargeable batteries30, and the barriers21contact and support the rechargeable batteries30.

Each storage space23has a structure with open opposite ends, and has a rectangular cross-section. The storage spaces23are arranged in parallel. The holder20has a cuboid shape, and the rechargeable batteries30are stacked and arranged by the holder20.

Two support bars25are provided at one side of the holder20, and the support bars25are formed in a direction along which the rechargeable batteries30are stacked (e.g., a stacking direction of the batteries30, or the z-axis direction inFIG. 3). The support bar25is fixed to one or more of the barriers21. Terminal holes251for accommodating the terminals31and32of a corresponding battery30, into which the positive electrode terminal31or the negative terminal32of a corresponding battery30may be inserted, are formed in, or defined by the support bar25.

The positive electrode terminal31and the negative electrode terminal32of each rechargeable battery30are inserted into a respective terminal hole251, and are electrically coupled to the neighboring rechargeable batteries30via a respective bus bar28. The bus bar28is formed in a plate shape, which extends in one direction (e.g., the z-axis direction inFIG. 3). The bus bar28may be welded to the positive electrode terminal31of a rechargeable battery30and to the negative electrode terminals32of an adjacent neighboring rechargeable battery30to connect the two rechargeable batteries30in series. However, the present invention is not limited thereto, and the bus bar28may connect the rechargeable batteries30in parallel.

A plurality of support protrusions253for contacting lateral sides (e.g., four lateral sides) of a corresponding bus bar28to support the bus bar28are formed in the support bar25. The support protrusions253guide where to position the bus bar28, and protect the bus bar28from an impact or vibration. The bus bar28has a quadrangular plate shape, and one bus bar28is formed to contact four support protrusions253at four respective sides of the bus bar28.

FIG. 5is a cross-sectional view of the battery module ofFIG. 1taken along the line V-V.

Referring toFIGS. 2 and 5, a support rib131protruding toward the first cover12is formed in the second cover13, and the support rib131contacts an inner surface of the receiving unit121. The support rib131is formed to extend in a circumferential direction of the second cover13(e.g., around a perimeter of the second cover13or a portion thereof), and has a quadrangular ring-shaped cross-section. A sealing member14is provided between the inner surface of the receiving unit121and the support rib131to form a seal therebetween. The sealing member14is extended in a quadrangular ring shape.

Accordingly, foreign materials may be prevented from entering between the first cover12and the second cover13. On the other hand, a battery region10a, into which the holder20is configured to be inserted, and a circuit region10b, into which the protective circuit module42and the converter41are configured to be inserted, are formed in the housing10.

A protection wall132, by which the battery region10aand the circuit region10bare divided, is formed in or within the first cover12. The protection wall132protrudes toward a top surface of the receiving unit121, and is separated from the top surface of the receiving unit121of the first cover12while having an interval therebetween. As such, when the protection wall132is separated from the top surface of the first cover12, the first cover12and the second cover13may press the holder20without being hindered by the protection wall132.

However, in other embodiments, when the protection wall132is made of an elastic material, an upper end of the protection wall132may contact the top surface of the receiving unit121of the first cover12. The protection wall132blocks the foreign materials from moving to the circuit region10bfrom the battery region10a, and reduces or prevents excessive pressure from being applied to the protective circuit module42by the housing10.

A bottom surface of the holder20contacts the second cover13, while a top surface of the holder20contacts the first cover12. The first cover12and the second cover13are provided to press the holder20while facing each other in a direction toward which the rechargeable batteries30are stacked (e.g., an inward direction), and as a result, the rechargeable batteries30are pressed by the holder20and the housing10, and are stably fixed.

As described above, according to the current exemplary embodiment, the rechargeable batteries30may be stably fixed without an end plate because they are fixed by the holder20and the housing10.

On the other hand, the converter41and the protective circuit module42are provided in the circuit region10b, and a voltage and a current may be controlled by the converter41. The protective circuit module42, which is a device for controlling charging and discharging operations of the rechargeable batteries30, includes a substrate421and a plurality of circuit elements423mounted on the substrate421.

The converter41is on the second cover13, and the protective circuit module42is on the converter41. A first support125protrudes from the first cover12, and may protrude downward from the inner top surface of the receiving unit121, and has a quadrangular cross-section. A first buffer plate45is provided under the first support125, between the first support125and the protective circuit module42, and prevents, or reduces the likelihood of, the circuit elements423being damaged by pressure of the first cover12.

A second support135protrudes upward from the second cover13, and has a quadrangular cross-section. A second buffer plate43having elasticity is on the second support135, and the converter41is on the second buffer plate43. The second buffer plate43prevents, or reduces the likelihood of, the converter41being damaged by the pressure of the second cover13.

The first buffer plate45and the second buffer plate43may be made of a thermally conductive polymer (TCP) or a thermally conductive silicon. A blocking plate46is provided between the converter41and the protective circuit module42to prevent the converter41and the protective circuit module42from being short-circuited, and to prevent heat that is generated from the converter41from being transmitted to the protective circuit module42. The blocking plate46is made of a heat-insulating material, and may be made of a heat-insulating polymer, which may be formed from a foaming resin.

FIG. 6is a longitudinal cross-sectional view of a battery module according to a second exemplary embodiment of the present invention.

Referring toFIG. 6, the battery module102according to the current exemplary embodiment includes a plurality of rechargeable batteries30, a holder20, a housing10, a protective circuit module52, and a converter51.

Because the battery module102according to the current exemplary embodiment has the same structure as the battery module101according to the first exemplary embodiment described above, with the exception of a structure of the protective circuit module52and the converter51, a repeated description of the same elements will be omitted.

The rechargeable batteries30are accommodated in a battery region10aof the housing10while being supported by the holder20, and the protective circuit module52and the converter51are accommodated in a circuit region10bof the housing10.

The converter51is on a second cover13, and the protective circuit module52is on the converter51. The protective circuit module52is configured to control charging and discharging operations of the rechargeable batteries30, and includes a substrate521, and circuit elements523mounted on the substrate521.

A first support125supporting the protective circuit module52protrudes from the first cover12, and protrudes downward from the receiving unit121, and has a quadrangular cross-section. A first thermally conductive plate55having excellent thermal conductivity is disposed under the first support125, between the first support125and the protective circuit module52. An upper thermal grease layer57is formed between the first thermally conductive plate55and the first support125. The first thermally conductive plate55transmits heat generated from the protective circuit module52to the first cover12.

The first thermally conductive plate55may be made of a metal such as aluminum, stainless steel, or the like. Alternatively, the first thermally conductive plate55may have a structure in which a surface of an elastic polymer is plated with a thin metal layer. In this case, the thin metal layer may be made of aluminum, gold, silver, etc.

A second support135supporting the converter51protrudes upward from the second cover13, and has a quadrangular cross-section. A second thermally conductive plate53having excellent thermal conductivity is on the second support135, and the converter51is on the second thermally conductive plate53.

A lower thermal grease layer56is formed between the second thermally conductive plate53and the second support135. The second thermally conductive plate53transmits heat generated from the converter51to the second cover13.

The second thermally conductive plate53may be made of a metal such as aluminum, stainless steel, or the like. Alternatively, the second thermally conductive plate53may have a structure in which a surface of an elastic polymer is plated with a thin metal layer. In this case, the thin metal layer may be made of aluminum, gold, silver, etc.

When the first thermally conductive plate55and the second thermally conductive plate53are provided, the heat generated from the protective circuit module52and the converter51can be rapidly discharged.