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EP-4250453-B1 - BATTERY PACK AND DEVICE INCLUDING THE SAME

EP4250453B1EP 4250453 B1EP4250453 B1EP 4250453B1EP-4250453-B1

Inventors

  • LEE, JUNG HOON
  • KIM, Dooseung
  • YANG, JAEHUN
  • KIM, SEHO
  • PARK, JEONG GI

Dates

Publication Date
20260506
Application Date
20220816

Claims (14)

  1. A battery pack (1000) comprising: a battery module (100) including a first sub-battery module (110) and a pair of second sub-battery modules (120) disposed on both sides of the first sub-battery module (110), respectively; a pack frame (1500) on which the battery module (100) is mounted; and a pair of connection portions (1300) that penetrate through the upper and lower portions of the first sub-battery module (110) and the pair of second sub-battery modules (120), respectively, wherein both sides of the pair of connection portions (1300) are fixed to the side surface portion (1510) of the pack frame (1500), wherein the first sub-battery module (110) includes a first battery cell stack (111) in which a plurality of first battery cells are stacked, and the first sub-battery module (110) further includes a pair of first module frames (115) respectively mounted to the upper and lower portions of the first battery cell stack (111), and wherein a first fixing member (117) is formed between the first module frame (115) and the first battery cell stack (111), and the first sub-battery module (110) is fixed to the bottom surface (1550) of the pack frame (1500), and wherein the second sub-battery module (120) includes a second battery cell stack (121) in which a plurality of second battery cells are stacked, and the second sub-battery module (120) further includes a pair of second module frames (125) respectively mounted to the upper and lower portions of the second battery cell stack (121), and wherein a second fixing member (127) is formed between the second module frame (125) and the second battery cell stack (121), and the second sub-battery module (120) moves along the longitudinal direction of the connection portion (1300)
  2. The battery pack according to claim 1, further comprising: a frame member (1700) that is mounted to the upper and lower portions of the first sub-battery module (110) and the pair of second sub-battery modules (120), wherein the frame member (1700) wraps at least a part of outer side surfaces of the pair of second sub-battery modules (120).
  3. The battery pack (1000) according to claim 2, wherein the frame member (1700) covers at least a part of the outer side surfaces of the sub-battery module (120), and wherein the shape of the frame member (1700) has the same shape as the upper and lower portions of the first sub-battery module (110) and the second sub-battery module (120).
  4. The battery pack (1000) according to claim 2, wherein: both side portions of the frame member (1700) move along the longitudinal direction of the connection portion (1300) together with the second sub-battery module (120), and a central portion of the frame member (1700) is stretched along the longitudinal direction of the connection portion (1300) together with the second sub-battery module (120).
  5. The battery pack (1000) according to claim 4, wherein: the frame member (1700) is made of at least one material selected from the group consisting of glass fiber reinforced plastic and carbon fiber reinforced plastic.
  6. The battery pack (1000) according to claim 2, wherein: the frame member (1700) includes a first frame member and a second frame member, the first frame member is mounted to the upper portion of the first sub-battery module (110) and the pair of second sub-battery modules (120), and the second frame member is mounted to the lower portions of the first sub-battery module (110) and the pair of second sub-battery modules (120).
  7. The battery pack (1000) according to claim 6, wherein: both ends of the first frame member extend along outer side surfaces of the pair of second sub-battery modules (120), both ends of the second frame member extend along outer side surfaces of the pair of second sub-battery modules (120), and the end of the first frame member and the end of the second frame member are spaced apart from each other.
  8. The battery pack (1000) according to claim 2, further comprising: an end plate (1800) disposed between the frame member and the side surface portion of the pack frame (1500).
  9. The battery pack (1000) according to claim 8, wherein: the end plate (1800) makes contact with an outer surface of the frame member disposed on the outer side surface of the pair of second sub-battery modules (120).
  10. The battery pack (1000) according to claim 9, wherein: the pair of connection portions (1300) penetrate through the upper and lower portions of the end plate (1800), respectively.
  11. The battery pack (1000) according to claim 1, wherein: both sides of the pair of connection portions (1300) are bolted to the side surface portion of the pack frame (1500), and the first sub-battery module (110) is bolted to the bottom surface (1550) of the pack frame (1500).
  12. The battery pack (1000) according to claim 1, wherein: the pair of connection portions (1300) each penetrates through the pair of first module frames (115), and each penetrates through the pair of second module frames (125).
  13. The battery pack (1000) according to claim 1, wherein: both side surfaces of the first battery cell stack (111) and both side surfaces of the second battery cell stack (121) are exposed toward the outside.
  14. The battery pack (1000) according to claim 1, wherein the first fixing member (117) and the second fixing member (127) are respective adhesive members, in particular adhesive members having thermal conductivity.

Description

[TECHNICAL FIELD] Cross Citation with Related Application(s) This application claims the benefit of Korean Patent Application No. 10-2021-0107955 filed on August 17, 2021 with the Korean Intellectual Property Office. The present disclosure relates to a battery pack and a device including the same, and more particularly, to a battery pack that prevents excessive warpage of frame members and degradation of the life of a battery cell when a swelling phenomenon occurs at the battery cell, and a device including the same. [BACKGROUND] Secondary batteries, which are easily applied to various product groups and has electrical characteristics such as high energy density, are universally applied not only for a portable device but also for an electric vehicle or a hybrid electric vehicle, an energy storage system or the like, which is driven by an electric driving source. Such secondary battery is attracting attention as a new environment-friendly energy source for improving energy efficiency since it gives a primary advantage of remarkably reducing the use of fossil fuels and also does not generate by-products from the use of energy at all. Currently commercialized secondary batteries include a nickel cadmium battery, a nickel hydrogen battery, a nickel zinc battery, and a lithium secondary battery. Among them, the lithium secondary battery has come into the spotlight because they have advantages, for example, hardly exhibiting memory effects compared to nickel-based secondary batteries and thus being freely charged and discharged, and having very low self-discharge rate and high energy density. Generally, the lithium secondary battery may be classified based on the shape of the exterior material into a cylindrical or prismatic secondary battery in which the electrode assembly is mounted in a metal can, and a pouch-type secondary battery in which the electrode assembly is mounted in a pouch made of an aluminum laminate sheet. Recently, along with a continuous rise of the necessity for a large-capacity secondary battery structure, including the utilization of the secondary battery as an energy storage source, there is a growing demand for a battery pack of a medium- and large-sized module structure which is an assembly of battery modules in which a plurality of secondary batteries are connected in series or in parallel. In such a battery module, a plurality of battery cells are connected to each other in series or in parallel to form a battery cell stack, thereby improving capacity and output. In addition, a plurality of battery modules may be mounted together with various control and protection systems such as a BMS (battery management system) and a cooling system to form a battery pack. An example secondary battery is known e.g. from WO 2021/024773 A1. This secondary battery comprises a battery module including a first sub-battery module and a pair of second sub-battery modules disposed on both sides of the first sub-battery module, a pack frame on which the battery module is mounted and a pair of connection portions, wherein the first sub-battery module is fixed to the bottom surface of the pack frame, and wherein the second sub-battery module moves along the longitudinal direction of the connection portion. Other example secondary batteries are known e.g. from JP 2011 049181 A, WO 2016/076308 A1, JP 2017 021960 A and CN 205 609 622 U. Fig. 1 is a top view of a conventional battery pack. Fig. 2 is a top view of the cell pack of Fig. 1 at end-of-life battery (EOL). Referring to Fig. 1, a conventional battery pack 10 includes a structure in which a battery module 11 is mounted between pack frames 15. However, generally, the battery cells 11a (Fig. 3) included in the battery module 11 repeat the process of expanding and contracting during charging and discharging processes. In one example, as shown in Fig. 2, the battery module 11 at the end-of-life battery may have a swelling portion 11s that expands toward the pack frame 15. Such a swelling portion 11s weakens the stiffness of the battery module 11, and causes a problem of the degradation of life due to pressure deviation applied to the battery cells 11a included in the battery module 11 (Fig. 3). Fig. 3 is a cross-sectional view of the battery module taken along the a-a' axis of Fig. 1. Referring to Fig. 3, the conventional battery module 11 is configured such that the battery cells 11a may be either adhered or pressed and fixed to the module frame 11b. Here, a compression pad 11p may be disposed on one side surface of the battery cell stack in which the battery cells 11a are stacked. In particular, as the amount of swelling of the battery cells 11a greatly increases in accordance with the recent trend of gradually increasing the capacity of the battery cells 11a, the amount of displacement to be absorbed by the module frame 11b also increases. However, even in the case of the compression pad 11p, it is difficult to sufficiently absorb the deformation applied towa