JP-2026514426-A - Battery module, and battery pack containing the same

JP2026514426AJP 2026514426 AJP2026514426 AJP 2026514426AJP-2026514426-A

Abstract

The battery module according to the present invention includes a cell stack consisting of stacked battery cells, a module case housing the cell stack and having a gas vent hole in a bottom plate located below the cell stack, and a vent guide unit comprising a needle member configured to protrude from the gas vent hole to create a hole in the battery cell, and a needle stopper member configured to prevent the needle member from protruding when not deformed by heat or external force.

Inventors

ジョン－フン・パク

Assignees

エルジーエナジーソリューションリミテッド

Dates

Publication Date: 20260511
Application Date: 20240812
Priority Date: 20230920

Claims (15)

A cell stack consisting of stacked battery cells, A module case that houses the cell stack and has a gas vent hole in the bottom plate located below the cell stack, A battery module comprising a vent guide unit having a needle member configured to protrude from the gas vent hole and create a hole in the battery cell, and a needle stopper member configured to prevent the needle member from protruding when it is not deformed by heat or external force.
The battery module according to claim 1, wherein the needle stopper member is formed of a material that can be heat-melted at a predetermined temperature.
The battery module according to claim 1 or 2, wherein the needle stopper member has a notch line that breaks upon a predetermined pressure.
The needle member is An elastic member positioned perpendicular to the gas vent hole, A needle portion is coupled to the upper end of the elastic member, The battery module according to claim 1 or 2, further comprising an elastic fixing portion coupled to the lower end of the elastic member and fixed to the bottom plate of the module case.
The needle stopper member is, A blocking portion that blocks the needle portion at the upper part of the gas vent hole, The battery module according to claim 4, further comprising: a stopper fixing portion connected to the blocking portion and fixed to the bottom plate of the module case.
The battery module according to claim 5, wherein a notch line is provided at the boundary between the blocking portion and the stopper fixing portion.
The battery module according to claim 5, wherein at least one of the blocking portion and the stopper fixing portion is made of a heat-meltable resin material.
The needle portion is, A needle plate is connected to the upper end of the elastic member and located below the blocking portion, The battery module according to claim 5, further comprising one or more needles protruding from the needle plate.
The battery module according to claim 8, wherein one or more of the needles are configured to be embedded inside the blocking portion.
The aforementioned battery cell is a pouch-type battery cell. The gas vent holes are provided at predetermined intervals along the width direction of the bottom plate. The battery module according to claim 1 or 2, wherein the gas vent holes are provided in the pouch-type battery cell at positions corresponding to the cell terraces formed by heat-sealing the pouch sheet.
The venting units are provided in each of the gas vent holes, The battery module according to claim 10, wherein the gas vent hole and the vent guide unit are provided on the front and rear sides of the bottom plate of the module case.
The aforementioned module case is A top plate that covers the upper part of the cell stack, The bottom plate covers the lower part of the cell stack, A pair of side plates that cover both sides of the cell stack, The battery module according to claim 1 or 2, comprising a pair of end covers that cover the front and rear of the cell stack, respectively.
A busbar electrically connected to electrode leads provided in the aforementioned battery cell, The present invention further includes a busbar frame that supports the busbar and has lead slots through which the electrode leads can pass, and is attached to the front or rear portion of the cell stack, The battery module according to claim 1 or 2, wherein the busbars include a first busbar and a second busbar arranged to overlap with the electrode leads in between, and the electrode leads are crimped and fixed between the first busbar and the second busbar.
The aforementioned battery cells are pouch-type battery cells, each with its wide surface facing upright and stacked in one direction. The cell stack includes a plurality of barrier plates inserted between the battery cells at predetermined intervals along the one direction to restrict the movement of heat or gas between the battery cells. The battery module according to claim 13, wherein each of the plurality of barrier plates has its end portion fitted into the busbar frame such that the battery cells and gas vent holes are divided into a predetermined number of units.
A battery pack comprising the battery module described in claim 1 or 2.

Description

This invention relates to a battery module and a battery pack containing the same, and more specifically, to a battery module and a battery pack containing the same that offer superior safety against thermal events. This application claims priority under Korean Patent Application No. 10-2023-0125887, filed on September 20, 2023, and all information disclosed in the specification and drawings of said application is incorporated herein by reference. The significant increase in technological development and demand for various mobile devices, electric vehicles, and energy storage systems (ESS) has led to a rapid increase in interest in and demand for rechargeable batteries as an energy source. While nickel-cadmium or nickel-metal hydride batteries have traditionally been widely used as rechargeable batteries, recently, lithium-ion batteries have become more common. They exhibit virtually no memory effect compared to nickel-based batteries, allowing for flexible charging and discharging, and boast extremely low self-discharge rates and high energy density. Such lithium-ion secondary batteries primarily use lithium-based oxides and carbon materials as the positive electrode active material and negative electrode active material, respectively. A lithium-ion secondary battery comprises an electrode assembly in which a positive electrode plate and a negative electrode plate, each coated with the positive electrode active material and negative electrode active material respectively, are arranged with a separator in between; and an outer casing, i.e., a battery case, that seals and houses the electrode assembly together with the electrolyte. Generally, rechargeable batteries are classified into two types based on the shape of their casing: can-type batteries, where the electrode assembly is housed in a metal can, and pouch-type batteries, where the electrode assembly is housed in an aluminum laminate sheet pouch. Lithium-ion batteries, which are widely used today, have an operating voltage of approximately 2.5V to 4.5V per unit. Therefore, in electric vehicles and power storage devices where large capacity and high output are required, battery modules or battery packs are constructed by connecting multiple lithium-ion batteries in series and/or parallel, and these are used as the energy source. In particular, to meet the output and capacity requirements of electric vehicles, battery modules and battery packs contain a very large number of lithium-ion batteries. Therefore, battery modules and battery packs require measures to prevent fires or reduce their spread in the event of a thermal event. For example, if a thermal event occurs in a battery module, and gas or flames are generated, causing heat to accumulate inside, heat can rapidly propagate between battery cells (thermal propagation). As a result, multiple battery cells may ignite simultaneously, making it difficult to suppress the thermal event, potentially leading to an explosion of the battery module and further damage. Therefore, when a thermal event occurs in the battery module, there is a need for a method to effectively dissipate thermal energy from within the battery module in order to delay the propagation of thermal runaway and ignition between battery cells as much as possible. This is a schematic perspective view of a battery module according to one embodiment of the present invention.Figure 1 is an exploded perspective view of the battery module.Figure 2 is a perspective view showing the cell stack.This is a perspective view showing a portion of a module case relating to one embodiment of the present invention.This is a magnified view of a portion of Figure 4.This is a perspective view showing the configuration of a vent induction unit according to one embodiment of the present invention.This figure shows an example of the application of a vent induction unit applied to a gas vent hole in a battery module according to one embodiment of the present invention.This is a schematic cross-sectional view of a battery module according to one embodiment of the present invention.This is an enlarged view of area A in Figure 8.This diagram corresponds to Figure 9 and shows an example where the needle stopper member is damaged and the needle portion pops out of the gas vent hole.This figure illustrates an example of assembly between a cell stack and a busbar frame according to one embodiment of the present invention.This figure shows a busbar frame in which the frame cover and crimped busbar shown in Figure 11 are joined together.This is a schematic cross-sectional view of an assembled cell stack and a busbar frame according to one embodiment of the present invention.This diagram schematically shows an automobile including a battery pack according to one embodiment of the present invention. The following describes preferred embodiments of the present invention in detail with reference to the attached drawings. Prior to this, terms and words used in this specifica