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KR-102963877-B1 - SECONDARY BATTERY AND BATTERY MODULE INCLUDING THE SAME

KR102963877B1KR 102963877 B1KR102963877 B1KR 102963877B1KR-102963877-B1

Abstract

A secondary battery according to one embodiment of the present invention comprises an electrode assembly and a battery case housing the electrode assembly, wherein the battery case comprises a first substrate layer, a second substrate layer, and a heat transfer blocking layer interposed between the first and second substrate layers, and the heat transfer blocking layer comprises a material having a lower thermal conductivity than that of the material comprising the first and second substrate layers.

Inventors

  • 민승준
  • 류덕현

Assignees

  • 주식회사 엘지에너지솔루션

Dates

Publication Date
20260511
Application Date
20210910

Claims (12)

  1. Electrode assembly; and It includes a battery case that houses the above electrode assembly, The battery case comprises a first substrate layer, a second substrate layer, and a heat transfer blocking layer interposed between the first and second substrate layers. The heat transfer blocking layer comprises a material having a lower thermal conductivity than the material included in the first and second substrate layers, and The first and second substrate layers are made of the same material and each comprises carbon steel.
  2. delete
  3. In paragraph 1, The above heat transfer blocking layer comprises a metal having a lower thermal conductivity than the carbon steel, in a secondary battery.
  4. In Paragraph 3, The above metal is one or more types selected from cast iron, lead, and stainless steel, in a secondary battery.
  5. In Paragraph 4, The above metal is a lead secondary battery.
  6. In paragraph 1, The above heat transfer blocking layer is a resin having lower thermal conductivity than the carbon steel, in a secondary battery.
  7. In paragraph 1, The above battery case is a secondary battery further comprising a plating layer formed on the outer surface of either the first substrate layer or the second substrate layer.
  8. In Paragraph 7, The above plating layer is a secondary battery containing nickel.
  9. In paragraph 1, It further includes a cap assembly coupled to the upper part of the battery case, and A secondary battery comprising at least a portion of the above-mentioned cap assembly including a first cap substrate layer, a second cap substrate layer, and a cap blocking layer interposed between the first and second cap substrate layers.
  10. In Paragraph 9, The above cap blocking layer is a secondary battery having a lower thermal conductivity compared to the material forming the first and second cap substrate layers.
  11. In Paragraph 10, The first and second cap substrate layers above comprise carbon steel, and The above cap blocking layer is a secondary battery containing lead.
  12. A battery module including a secondary battery according to paragraph 1.

Description

Secondary battery and battery module including the same The present invention relates to a secondary battery and a battery module including the same, and more specifically, to a cylindrical secondary battery with improved safety at high temperatures and a battery module including the same. Recently, as the demand for portable electronic products such as laptops, video cameras, and mobile phones has increased rapidly, and the development of electric vehicles, energy storage batteries, robots, and satellites has accelerated, much research is being conducted on secondary batteries used as their power sources. Rechargeable batteries are classified according to the shape of the battery case into cylindrical batteries, in which the electrode assembly is housed in a cylindrical metal can; prismatic batteries, in which the electrode assembly is housed in a rectangular metal can; and pouch batteries, in which the electrode assembly is housed in a pouch-type case made of aluminum laminate sheets. Among these, cylindrical batteries have the advantage of relatively high capacity and structural stability. The electrode assembly embedded in the battery case is a rechargeable power generator composed of a stacked structure of a positive electrode, a separator, and a negative electrode, and is classified into jelly-roll type, stack type, and stack/folding type. The jelly-roll type is a form in which a separator is interposed between long sheet-type positive and negative electrodes coated with active material and wound; the stack type is a form in which multiple positive and negative electrodes of a predetermined size are sequentially stacked with a separator interposed; and the stack/folding type is a composite structure of the jelly-roll type and the stack type. Among these, the jelly-roll type electrode assembly has the advantages of being easy to manufacture and having a high energy density per unit weight. Meanwhile, secondary batteries include, for example, nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and lithium secondary batteries. Among these, lithium secondary batteries are widely used in the field of advanced electronic devices due to their advantages, such as the ability to freely charge and discharge with almost no memory effect compared to nickel-based secondary batteries, a very low self-discharge rate, high operating voltage, and high energy density per unit weight. In particular, recently, there has been an increasing application of materials with higher silicon content in the anode or higher nickel content in the cathode to develop high-capacity batteries. However, in this case, the high silicon content in the anode causes severe volume expansion during charging and discharging, leading to the problem of ignition in high-temperature environments. Additionally, regarding the cathode, the lack of thermal stability in materials with high nickel content causes the cathode structure to collapse at high temperatures, also resulting in ignition in such environments. FIG. 1 is a perspective view showing a secondary battery according to one embodiment of the present invention. Figure 2 is a cross-sectional view taken along the cutting line A-A' of Figure 1. FIG. 3 is a cross-sectional view of a secondary battery according to another embodiment of the present invention. Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. The present invention may be embodied in various different forms and is not limited to the embodiments described herein. To clearly explain the present invention, parts unrelated to the explanation have been omitted, and the same reference numerals are used for identical or similar components throughout the specification. Furthermore, the size and thickness of each component shown in the drawings are depicted arbitrarily for convenience of explanation, and thus the present invention is not necessarily limited to what is illustrated. Thicknesses have been enlarged in the drawings to clearly represent various layers and regions. Additionally, for convenience of explanation, the thickness of some layers and regions has been exaggerated in the drawings. Furthermore, when a part such as a layer, membrane, region, or plate is said to be "on" or "on" another part, this includes not only the case where it is "directly above" the other part, but also the case where there is another part in between. Conversely, when a part is said to be "directly above" another part, it means that there is no other part in between. Also, saying that a part is "on" or "on" a reference part means that it is located above or below the reference part, and does not necessarily mean that it is located "on" or "on" facing the opposite direction of gravity. Furthermore, throughout the specification, when a part is described as "including" a certain compon