Patent Description:
The present invention relates to a battery module including a plurality of cell module assemblies, each of which has an individual housing, and module plates.

With technological development of mobile devices, such as mobile phones, laptop computers, camcorders, and digital cameras, and an increase in demand therefor, research on secondary batteries, which are capable of being charged and discharged, has been actively conducted. In addition, secondary batteries, which are energy sources substituting for fossil fuels causing air pollution, have been applied to an electric vehicle (EV), a hybrid electric vehicle (HEV), and a plug-in hybrid electric vehicle (P-HEV), and therefore there is an increasing necessity for development of secondary batteries.

There are a lithium ion battery, a lithium polymer battery, a nickel-cadmium battery, a nickelhydride battery, and a nickel-zinc battery as secondary batteries that are widely used at present. The operating voltage of a unit secondary battery cell, i.e. a unit battery cell, is about <NUM>. 0V to <NUM>. In the case in which output voltage higher than the above operating voltage is required, therefore, a plurality of battery cells may be connected to each other in series to constitute a cell module assembly. In addition, cell module assemblies may be connected to each other in series or in parallel to constitute a battery module depending on required output voltage or charge and discharge capacities. In general, a battery pack is manufactured using at least one battery module by adding an additional component. <CIT> according to its title states a battery module of cell edge direct cooling scheme and battery pack comprising same. <CIT> according to its title states a battery module.

A conventional battery module will be described with reference to <FIG> and <FIG>. In general, a plurality of battery cells is received in a cartridge <NUM> generally made of a plastic material without a separate housing to form a cell module assembly <NUM>. At least one cell module assembly <NUM>, formed as described above, is received in a module housing constituted by an upper module plate <NUM>, a lower module plate <NUM>, and side module plates <NUM> and <NUM> to manufacture a battery module <NUM>.

For this battery module, however, several cell module assemblies are arranged and mounted in a single space defined in the module housing. When an event, such as fire breakout, occurs in a specific cell module assembly, therefore, the event propagates to an adjacent cell module assembly, whereby the adjacent cell module assembly may also be damaged.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide a battery module configured such that each cell module assembly is received in an individual housing in the state in which a module housing is removed from the battery module.

In order to accomplish the above object, a battery module according to the present invention includes a plurality of cell module assemblies and a pair of module plates, wherein each of the cell module assemblies includes a plurality of battery cells and an individual housing configured to receive the plurality of battery cells, the individual housing includes an upper plate located at the upper part of the plurality of battery cells, a lower plate located at the lower part of the plurality of battery cells, and two side plates located at opposite side surfaces of the plurality of battery cells, the two side plates being configured to connect the upper plate and the lower plate to each other, excluding the front and the rear of the plurality of battery cells, from which electrode leads protrude, and each of the pair of module plates has a size that covers a corresponding one of the entire front and the entire rear of the plurality of cell module assemblies, from which the electrode leads protrude, the pair of module plates being located respectively at the front and the rear of the plurality of cell module assemblies so as to be fastened to the plurality of cell module assemblies.

Also, in the battery module according to the present invention, a space portion is formed between each of the side plates of the individual housing and a side plate of a neighboring individual housing.

In addition, the battery module according to the present invention may further include a busbar unit located between the plurality of battery cells and each of the module plates, the busbar unit being electrically connected to the electrode leads.

Also, in the battery module according to the present invention, each of the upper plate, the lower plate, and the side plates of the individual housing may be provided with a fastening portion for coupling with the other plates.

Also, in the battery module according to the present invention, an insulating material configured to inhibit heat transfer between the cell module assemblies may be further added to the space portion.

Also, in the battery module according to the present invention, a flame retardant material configured to inhibit flame transfer between the cell module assemblies may be further added to the space portion.

Also, in the battery module according to the present invention, the upper plate and the lower plate of the individual housing may be coupled to the side plates by mechanical fastening or welding.

Also, in the battery module according to the present invention, distal end portions of the upper plate, the lower plate, and the side plates of the individual housing may be formed so as to overlap each other when the upper plate and the lower plate are coupled to the side plates in order to improve sealability between the plates.

Also, in the battery module according to the present invention, each of the module plates may include a fastening portion for coupling with the individual housing and a venting portion configured to discharge venting gas.

Also, in the battery module according to the present invention, each of the module plates may be coupled to the cell module assemblies by mechanical fastening.

Also, in the battery module according to the present invention, the individual housing may be made of a metal material.

In addition, a battery pack according to the present invention includes at least one battery module.

A battery module according to the present invention has an advantage in that each cell module assembly is received in an individual housing, and therefore when an event, such as fire breakout, occurs in a specific cell module assembly, the event is prevented from propagating to an adjacent cell module assembly.

In addition, the battery module according to the present invention has advantages in that individual housings are fastened to each other in the state of being spaced apart from each other to form a space portion, whereby heat transfer is prevented, and in that an insulating material or a flame retardant material may be further added to the space portion.

Hereinafter, a battery module according to the present invention will be described with reference to the accompanying drawings.

<FIG> is a schematic view of a battery module according to a first preferred embodiment of the present invention, and <FIG> is an exploded perspective view of the battery module.

The battery module <NUM> will be described with reference to <FIG> and <FIG>. First, the battery module <NUM> includes at least one cell module assembly (CMA) having a plurality of battery cells received in an individual housing <NUM> and module plates <NUM> configured to cover the front and the rear of the cell module assembly, at which electrode leads protrude from the battery cells in the cell module assembly. In addition, the battery module <NUM> further includes a busbar unit <NUM> provided between the cell module assembly and each of the module plates, the busbar unit being configured to electrically connect the electrode leads to each other. Also, in the battery module <NUM>, a space portion <NUM> is formed between adjacent individual housings <NUM>.

Each of the battery cells used in the battery module <NUM> according to the present invention may be constituted by a secondary battery. Based on the kind and shape of a sheathing member, the secondary battery may be generally classified as a pouch-shaped secondary battery, a cylindrical secondary battery, or a prismatic secondary battery. Preferably, a pouch-shaped secondary battery may be used as the battery cell according to the present invention.

The pouch-shaped secondary battery may include an electrode assembly, a battery case configured to receive the electrode assembly, and a pair of electrode leads protruding forwards and rearwards from the battery case.

The individual housing <NUM> will be described in detail with reference to <FIG>. The individual housing <NUM> includes an upper plate <NUM>, a lower plate <NUM>, and side plates <NUM> located at the upper part, the lower part, and the side surfaces of the cell module assembly, respectively. Each of the plates <NUM>, <NUM>, and <NUM> is provided with a fastening portion <NUM> for coupling with the other plates. Fastening between the plates <NUM>, <NUM>, and <NUM> is achieved through the fastening portions <NUM>. Any of various conventional methods, such as mechanical fastening using bolts or welding, may be used as a fastening method.

Also, in the battery module <NUM> according to the present invention, the fastening portions <NUM> formed at the side plates <NUM> of adjacent individual housings <NUM> so as to correspond to each other are fastened to each other using the mechanical fastening or welding method, whereby the individual housings <NUM> are connected to each other. As shown in <FIG>, the space portion <NUM> is formed between the side plates of the individual housings <NUM> connected to each other, as described above. The space portion itself may serve to inhibit heat transfer between the individual housings <NUM>. In addition, an insulating material configured to block heat transfer or a flame retardant material configured to prevent propagation of flames at the time of fire breakout may be inserted into the space portion <NUM>.

In addition, each of the plates <NUM>, <NUM>, and <NUM> of the individual housing <NUM> may be made of a metal material. The plates <NUM>, <NUM>, and <NUM>, each of which is made of a metal material, as described above, are coupled to each other to form the individual housing. Consequently, the individual housing has higher mechanical strength than a cartridge used in a conventional battery module, which is generally made of a plastic material.

Coupling of the individual housing through the plates <NUM>, <NUM>, and <NUM> will be described in more detail with reference to <FIG>. A distal end portion 113a of each of the side plates <NUM> configured to abut a corresponding one of the upper plate <NUM> and the lower plate <NUM> at the time of fastening is bent so as to overlap a distal end portion of the corresponding one of the upper plate <NUM> and the lower plate <NUM>, whereby sealability of the individual housing <NUM> after fastening is improved. In the case in which venting gas is generated from one or more battery cells in a specific cell module assembly, therefore, it is possible to guide the venting gas to the front and the rear of the individual housing <NUM>, at which the plates <NUM>, <NUM>, and <NUM> are not located, since sealability of the individual housing <NUM> is improved, as described above. As a result, even though venting gas is generated in a specific cell module assembly, a cell module assembly adjacent thereto is not affected, whereby it is possible to improve reliability of the battery module.

Meanwhile, the module plate <NUM> will be described in detail with reference to <FIG>. The module plate <NUM> includes an assembly portion <NUM> for assembly with the individual housing <NUM> and a venting portion <NUM> configured to discharge venting gas, and has a size that covers the entire front and the entire rear of the cell module assemblies located in the battery module. The module plate <NUM> and the individual housing <NUM> may be assembled by mechanical coupling between the assembly portion <NUM> of the module plate <NUM> and the fastening portion <NUM> of the individual housing <NUM> using bolts. The module plate <NUM>, assembled as described above, may also serve to additionally fix the individual housings <NUM>. Since assembly is achieved by mechanical coupling, rather than welding, it is possible to prevent the battery cells in the cell module assembly from being damaged by heat generated at the time of welding. Furthermore, even in the case in which a specific cell module assembly malfunctions, the module plate <NUM> may be easily separated from the individual housing coupled thereto in order to repair or remove the defective cell module assembly.

Claim 1:
A battery module (<NUM>), comprising:
a plurality of cell module assemblies; and
a pair of module plates (<NUM>),
wherein each of the cell module assemblies comprises a plurality of battery cells and an individual housing (<NUM>) configured to receive the plurality of battery cells,
wherein the individual housing (<NUM>) comprises:
an upper plate (<NUM>) located at an upper part of the plurality of battery cells,
a lower plate (<NUM>) located at a lower part of the plurality of battery cells, and
two side plates (<NUM>) located at opposite side surfaces of the plurality of battery cells, the two side plates (<NUM>) being configured to connect the upper plate (<NUM>) and the lower plate (<NUM>) to each other, excluding a front and a rear of the plurality of battery cells, from which electrode leads protrude, and
wherein each of the pair of module plates (<NUM>) has a size that covers a corresponding one of an entire front and an entire rear of the plurality of cell module assemblies, from which electrode leads protrude, the pair of module plates (<NUM>) being located respectively at the front and the rear of the plurality of cell module assemblies so as to be fastened to the plurality of cell module assemblies, and
wherein a space portion (<NUM>) is formed between each of the side plates (<NUM>) of the individual housing (<NUM>) and a side plate (<NUM>) of a neighboring individual housing (<NUM>).