Secondary Battery and Secondary Battery Module Including the Same

Patent metadata

Field	Value
Publication number	US-2023378566-A1
Application number	US-202218031234-A
Country	US
Kind code	A1
Filing date	Aug 24, 2022
Priority date	Aug 25, 2021
Publication date	Nov 23, 2023
Grant date	—

Abstract

A secondary battery includes a separator in an electrode assembly thereof that has a sealing part for individually sealing a positive electrode and a negative electrode and has a double sealing structure. The double sealing structure including a first sealing part and a second sealing part so that an accommodation part for accommodating a fire extinguishing agent is provided at an end part of the negative electrode. Further, the secondary battery includes a flame propagation prevention part disposed on an outer surface of the electrode assembly so that a flame generated during thermal runaway of the secondary battery can be blocked in a stage in which the electrode assembly is positioned inside the battery cell, and thus a longer flame propagation time can be induced.

First claim

1 . A secondary battery comprising:
an electrode assembly having a stacked structure, the electrode assembly including a plurality of positive electrodes, a plurality of negative electrodes, and a plurality of separators, the plurality of separators being disposed on opposing surfaces of the plurality of negative electrodes, wherein the plurality of separators are additionally positioned at an outermost surface of the plurality of positive electrodes and an outermost surface of the plurality of negative electrodes; and a battery case, the battery case being configured to accommodate the electrode assembly, wherein the plurality of separators include a first sealing part and a second sealing part, the first sealing part being configured to individually bond a first end part of each of the plurality of separators together, the first sealing part being disposed in a first exterior region of the electrode assembly, the first exterior region being positioned at an outermost extremity of the plurality of separators, and a second sealing part configured to individually bond a second end part of each of the plurality of separators together, the second sealing part being disposed in a second exterior region of the electrode assembly, the second exterior region being positioned between a center of the electrode assembly and the first exterior region of the electrode assembly, wherein the second sealing part is configured to form an accommodation part, the accommodation part being positioned between the second sealing part and the first sealing part.

2 . The secondary battery of claim 1 , wherein the accommodation part includes a fire extinguishing agent, the firing extinguishing agent being configured to phase shift to a gas phase in a range of 100° C. to 300° C.

3 . The secondary battery of claim 2 , wherein the fire extinguishing agent includes one or more of halogenated carbon, a halogenated ketone, a halogenated alkane, or an inert gas.

4 . The secondary battery of claim 1 , wherein the first sealing part is configured to be formed by adhesion or thermal fusing of the first end parts of the plurality of separators together, and the second sealing part being configured to be formed by adhesion or thermal fusing of the second end part of the plurality of separators together.

5 . The secondary battery of claim 1 , wherein an average thickness of the plurality of separators ranges from 5 μm to 50 μm.

6 . The secondary battery of claim 1 , wherein the electrode assembly includes a flame propagation prevention part disposed on a first outer surface of the electrode assembly, wherein the first outer surface lacks a tab.

7 . The secondary battery of claim 1 , wherein the electrode assembly includes a plurality of unit cells, the plurality of cells being stacked upon each other in a stacking dimension, and
a flame propagation prevention part, the flame propagation prevention part being configured to be inserted between the plurality of unit cells in the stacking dimension.

8 . The secondary battery of claim 6 , wherein the flame propagation prevention part includes a flame propagation prevention sheet comprising a silicate sheet made of a silicate containing one or more elements of silicon (Si), aluminum (Al), iron (Fe), magnesium (Mg), manganese (Mn), titanium (Ti), sodium (Na), potassium (K), fluorine (F), or oxygen (O).

9 . The secondary battery of claim 6 , wherein the flame propagation prevention part includes a flame propagation prevention sheet that includes one or more of muscovite, fenzite, celonite, paragonite, margarite, phlogopite, biotite, anite, ferrous mica, siderophilite, clintonite, lithium muscovite, trillithionite, polylithionite, zinnwaldite, or taniolite.

10 . The secondary battery of claim 8 , wherein the silicate sheet contains a binder in an amount of 1 to 20 parts by weight with respect to 100 parts by weight of a total amount of a silicate, and
the binder includes one or more of polyethylene (PE), polypropylene (PP), or a polyolefin, the polyolefin including a copolymer of PE and PP, a polyamide including nylon, or heat-resistant silicone.

11 . The secondary battery of claim 6 , wherein the flame propagation prevention part includes a flame propagation prevention sheet that includes a protrusion, a concave part, or a predetermined pattern of repeating protrusions and concave parts on a first surface of the flame propagation prevention sheet.

12 . A secondary battery module comprising:
the secondary battery according to claim 1 ; and a module case, the module case being configured to accommodate the secondary battery.

13 . The secondary battery of claim 7 , wherein the flame propagation prevention part includes a flame propagation prevention sheet comprising a silicate sheet made of a silicate containing one or more elements of silicon (Si), aluminum (Al), iron (Fe), magnesium (Mg), manganese (Mn), titanium (Ti), sodium (Na), potassium (K), fluorine (F), or oxygen (O).

14 . The secondary battery of claim 7 , wherein the flame propagation prevention part includes a flame propagation prevention sheet that includes one or more of muscovite, fenzite, celonite, paragonite, margarite, phlogopite, biotite, anite, ferrous mica, siderophilite, clintonite, lithium muscovite, trillithionite, polylithionite, zinnwaldite, or taniolite.

Assignees

• Lg Energy Solution Ltd

Inventors

• Park Su Han
• Lee Young Hwan

Classifications

• H01M10/654 Primary

  located inside the innermost case of the cells, e.g. mandrels, electrodes or electrolytes · CPC title

• H01M50/105

  Pouches or flexible bags · CPC title

• H01M50/463

  Separators, membranes or diaphragms characterised by their shape · CPC title

• H01M50/46

  Separators, membranes or diaphragms characterised by their combination with electrodes · CPC title

• H01M50/186

  characterised by the disposition of the sealing members · CPC title