US-12620665-B2 - Battery pack and device including the same

Abstract

An embodiment of the present invention provides a battery pack including: a plurality of battery modules each configured to include a battery cell stack on which a plurality of battery cells are stacked and a module frame for accommodating the battery cell stack; a pack frame configured to accommodate the battery modules; and fixing brackets respectively positioned on front and rear surfaces of the battery module, wherein protrusions are respectively formed on the front and rear surfaces of the battery module, and the fixing brackets surround the protrusions and are coupled to the pack frame.

Inventors

• Won Kyoung Park
• JunYeob SEONG
• Honggoo HAN
• Hyun Seop YUN

Assignees

• LG ENERGY SOLUTION, LTD.

Dates

Publication Date

20260505

Application Date

20210309

Priority Date

20200429

Claims (16)

1. 1 . A battery pack comprising: a plurality of battery modules each including a battery cell stack in which a plurality of battery cells are stacked, a module frame accommodating the battery cell stack therein, and front and rear end plates positioned on opposite respective sides of the module frame, each battery module having a protrusion formed on a front surface of the front end plate of the battery module and a protrusion formed on a rear surface of the rear end plate of the battery module; a pack frame configured to accommodate the battery modules thereon; and a respective front fixing bracket positioned on the front surface of the front end plate of each battery module, and a respective rear fixing bracket positioned on the rear surface of the rear end plate of each battery module, wherein the corresponding, respective front fixing bracket positioned on the front surface of the front end plate of the corresponding battery module: surrounds the respective protrusion formed on the front surface thereof; and is directly coupled to the pack frame and directly contacts the pack frame, and the corresponding, respective rear fixing bracket positioned on the rear surface of the rear end plate of the corresponding battery module; surrounds the respective protrusion formed on the rear surface thereof; and is directly coupled to the pack frame and directly contacts the pack frame, and wherein each of the front and rear end plates is not directly coupled to the pack frame using bolts and is indirectly coupled to the pack frame by the respective front and rear fixing brackets having an interference fit with the protrusions, such that a closest distance between opposite ones of the front and rear fixing brackets is less than a farthest linear distance between opposite ones of the protrusions, wherein each battery module includes a heat sink positioned below a bottom portion of the respective module frame, and the bottom portion of each module frame simultaneously constitutes an upper plate of the respective heat sink.
2. 2 . The battery pack of claim 1 , wherein the protrusions are formed at a lower edge of the front surface of each battery module and a lower edge of the rear surface of each battery module, respectively, and the fixing brackets each include a fixing unit surrounding an upper surface and a side surface of a respective one of the protrusions.
3. 3 . The battery pack of claim 1 , wherein each fixing bracket has a bracket hole formed therein, the pack frame has a first pack frame hole formed therein, and the battery pack further comprises first bolts each extending through a corresponding one of the first pack frame holes and a corresponding one of the bracket holes and first nuts each coupled to a corresponding one of the first bolts.
4. 4 . The battery pack of claim 1 , further comprising insulating members positioned between the protrusions of each battery module and the pack frame, each insulating member positioned between a respective one of the protrusions and the pack frame.
5. 5 . The battery pack of claim 1 , wherein the pack frame includes a pack refrigerant supply pipe configured to supply a refrigerant and refrigerant supply openings connected to the pack refrigerant supply pipe, each heat sink includes an inlet through which the refrigerant is introduced, and each inlet and a corresponding one of the refrigerant supply openings are connected to each other.
6. 6 . The battery pack of claim 5 , further comprising gaskets each positioned between a respective one of the heat sinks and the pack frame, each gasket surrounding a respective one of the inlets and a respective one of the refrigerant supply openings.
7. 7 . The battery pack of claim 1 , wherein the pack frame includes a pack refrigerant discharge pipe configured to discharge a refrigerant and refrigerant discharge openings connected to the pack refrigerant discharge pipe, each heat sink includes an outlet through which the refrigerant is discharged, and each outlet and a corresponding one of the refrigerant discharge openings are connected to each other.
8. 8 . The battery pack of claim 1 , wherein each module frame includes a module frame extension formed by extending a portion of the bottom portion of the module frame, and each heat sink includes a heat sink extension extending from a side of the heat sink to a portion where a corresponding one of the module frame extensions is positioned.
9. 9 . The battery pack of claim 8 , wherein the pack frame has a second pack frame hole formed therein, each module frame extension has a first mounting hole formed therein, each heat sink extension has a second mounting hole formed therein, and the battery pack further comprises second bolts each extending through a corresponding one of the first mounting holes, a corresponding one of the second mounting holes, and the second pack frame hole, and second nuts each coupled to a corresponding one of the second bolts.
10. 10 . The battery pack of claim 8 , wherein each fixing bracket includes a cover portion covering a corresponding one of the module frame extensions and a corresponding one of the heat sink extensions.
11. 11 . The battery pack of claim 10 , wherein the pack frame has a drain hole formed in a portion of the pack frame and covered by a corresponding one of the cover portions.
12. 12 . The battery pack of claim 8 , wherein each heat sink includes an inlet configured to receive inflow of the refrigerant therethrough, and at least a portion of each of the inlets is positioned in a corresponding one of the heat sink extensions.
13. 13 . The battery pack of claim 1 , wherein each heat sink and the bottom portion of the corresponding module frame constitute a refrigerant passage, and the bottom portion of the corresponding module frame is in contact with the refrigerant.
14. 14 . The battery pack of claim 1 , wherein each heat sink includes a lower plate joined to the bottom portion of the corresponding module frame and a depressed portion extending downwardly from the bottom portion of the corresponding module frame.
15. 15 . The battery pack of claim 1 , wherein the pack frame includes a support frame for supporting each of the battery modules and a lower frame positioned below the support frame, and the support frame includes a pack refrigerant supply pipe and a pack refrigerant discharge pipe positioned between the support frame and the lower frame.
16. 16 . A device comprising the battery pack according to claim 1 .

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a national phase entry under 35 U.S.C. § 371 of International Application No. PCT/KR2021/002907, filed on Mar. 9, 2021, published in Korean, which claims priority to Korean Patent Application No. 10-2020-0052254, filed on Apr. 29, 2020, the entire contents of which are hereby incorporated herein by reference. TECHNICAL FIELD Background Art In modern society, as portable devices such as mobile phones, laptops, camcorders, and digital cameras are used in daily life, development of techniques related to mobile devices as described above is becoming active. In addition, a rechargeable battery capable of charging and discharging is a measure to solve air pollution such as from conventional gasoline vehicles using fossil fuels, is used as a power source for electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (P-HEV), and thus a need for development of rechargeable batteries is increasing. Currently commercially available rechargeable batteries include a nickel cadmium battery, a nickel hydrogen battery, a nickel zinc battery, and a lithium rechargeable battery, and among them, the lithium rechargeable battery has little memory effect compared to nickel-based rechargeable batteries, so it is in the spotlight as it is freely charged and discharged, has a very low self-discharge rate, and has high energy density. Such a lithium rechargeable battery mainly uses a lithium-based oxide and a carbon material as a positive electrode active material and a negative electrode active material, respectively. The lithium rechargeable battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate to which a positive electrode active material and a negative electrode active material are respectively applied with a separator therebetween, and a battery case for sealing and housing the electrode assembly together with an electrolyte. In general, a lithium rechargeable battery may be classified into a can-type rechargeable battery in which an electrode assembly is embedded in a metal can, and a pouch-type rechargeable battery in which an electrode assembly is embedded in a pouch of an aluminum laminate sheet depending on a shape of an exterior material. In the case of rechargeable batteries used for small devices, 2-3 battery cells are positioned, but in the case of rechargeable batteries used for mid- to large-sized devices such as vehicles, a battery module in which a plurality of battery cells are electrically connected is used. In such a battery module, a plurality of battery cells are connected in series or parallel to each other to form a battery cell stack, thereby improving capacity and output. In addition, one or more battery modules may be mounted together with various control and protection systems, such as a battery management system (BMS) and a cooling system, to constitute a battery pack. In the case of a rechargeable battery, when a temperature thereof is higher than an appropriate temperature, performance of the rechargeable battery may be deteriorated, and in severe cases, there is a risk of explosion or ignition. In particular, in a battery module or battery pack including a plurality of rechargeable batteries, that is, a battery cell, heat from a plurality of battery cells is added up in a narrow space, so that the temperature may rise more rapidly and severely. In other words, in the case of a battery module in which a plurality of battery cells are stacked and a battery pack in which such a battery module is mounted, high output may be obtained, but it is not easy to remove heat generated in the battery cells during charging and discharging. When heat dissipation of the battery cells is not properly performed, the deterioration of the battery cells is accelerated and a lifespan thereof is shortened, and a possibility of explosion or ignition increases. Further, in the case of a battery module included in a vehicle battery pack, it may be frequently exposed to direct sunlight, and may be placed in a high temperature condition such as in summer or in a desert area. Accordingly, when configuring the battery module or battery pack, it can be said that it is very important to secure stable and effective cooling performance. FIG. 1 illustrates a partial perspective view of a conventional battery pack, and FIG. 2 illustrates a partial perspective view showing a mounting method of a battery module included in the battery pack of FIG. 1. Referring to FIG. 1 and FIG. 2, a conventional battery pack may include a plurality of battery modules 10 and a pack frame 11 in which the battery modules 10 are accommodated. For convenience of description, only one battery module is illustrated in FIG. 1. In the conventional battery pack, a refrigerant pipe is provided for cooling the battery modules 10, and a refrigerant is supplied through a refrigerant pipe connector 13 connected to the re