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CN-118339705-A - Minerals to improve thermal insulation for under-hood applications for battery safety automotive electrification

CN118339705ACN 118339705 ACN118339705 ACN 118339705ACN-118339705-A

Abstract

In one aspect of the present disclosure, a thermal runaway protective film for a lithium ion battery is provided, the film comprising at least one protective layer comprising at least one silicone resin and at least one silicate composite in an amount of at least 40 wt% based on the total weight of the at least one protective layer.

Inventors

  • ROSEN KERSTIN C
  • SCHASKE MARTIN
  • KUESTERS CHRISTOPH
  • MIDDENDORF KLAUS H G

Assignees

  • 3M INNOVATIVE PROPERTIES COMPANY

Dates

Publication Date
20240712
Application Date
20221130
Priority Date
20211201

Claims (15)

  1. 1. A thermal runaway protective film for a lithium ion battery, the film comprising At least one protective layer comprising at least one silicone resin and at least one silicate composite in an amount of at least 40 wt% based on the total weight of the at least one protective layer.
  2. 2. The thermal runaway protective film according to claim 1, wherein the at least one protective layer comprises at least 45 wt. -%, preferably at least 50 wt. -%, more preferably at least 60 wt. -%, even more preferably at least 70wt. -% of the at least one silicate compound, based on the total weight of the at least one layer.
  3. 3. The thermal runaway protective film according to any of the preceding claims, wherein the at least one silicone resin is at least one silicone rubber.
  4. 4. The thermal runaway protective film according to any of the preceding claims, wherein the at least one silicate composite is selected from the group consisting of kaolin, metakaolin, mullite, wollastonite, and any combinations and mixtures thereof, preferably metakaolin, mullite, and wollastonite, and any combinations and mixtures thereof, still more preferably mullite and/or wollastonite, even more preferably mullite.
  5. 5. A thermal runaway protective film according to any of the preceding claims, further comprising at least one polymer grid, preferably a thermoplastic grid.
  6. 6. The thermal runaway protective film of claim 5, wherein the polymer mesh is a thermoplastic mesh, or a thermoplastic scrim.
  7. 7. The thermal runaway protective film of claim 6, wherein the thermoplastic mesh comprises at least one thermoplastic material selected from the group consisting of: acrylonitrile Butadiene Styrene (ABS), polyamide (PA), polylactic acid ester (PLA), polymethyl methacrylate (PMMA), polycarbonate (PC), polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polystyrene (PS), polyetheretherketone (PEEK), polyvinylchloride (PVC) and any combinations and mixtures thereof, preferably polypropylene and polyamide.
  8. 8. The thermal runaway protective film according to any of the preceding claims, wherein the at least one protective layer further comprises at least one endothermic filler, or wherein the thermal runaway protective film further comprises at least one additional layer comprising at least one endothermic filler, preferably wherein the at least one additional layer comprises silicone rubber.
  9. 9. The thermal runaway protective film according to claim 8, wherein the at least one heat absorbing filler is selected from the group consisting of sodium metasilicate pentahydrate, monoammonium phosphate, inorganic carbonates, preferably calcium magnesium carbonate and calcium silicon magnesium carbonate, metal hydroxides, preferably aluminum hydroxide and magnesium hydroxide, mineral compounds comprising crystal water, preferably aluminum hydroxide, magnesium carbonate, magnesium oxide, mg (OH) 2 4MgCO 3 4H 2 O、MgCl 2 5Mg(OH) 2 7H 2 O, and any combinations and mixtures thereof.
  10. 10. The thermal runaway protective film according to any of the preceding claims, wherein the at least one protective layer comprises an inorganic filler having a bulk density of less than 3.5g/cm 3 and/or a thermal conductivity TC of less than 0.2W/m K at 25 ℃ according to ASTM D5470.
  11. 11. The thermal runaway protective film according to any of the preceding claims, wherein the thermal runaway protective film exhibits a thermal conductivity ASTM D5470 of less than 1W/m K, preferably less than 0.8W/m K, still more preferably less than 0.7W/m K.
  12. 12. A thermal runaway protective film according to any of the preceding claims, wherein the battery protective film has a thickness in the range of 0.5mm to 3.5mm, preferably 0.6mm to 3.2mm, more preferably 0.7mm to 3 mm.
  13. 13. The thermal runaway protective film according to any of the preceding claims, wherein the thermal runaway protective film further comprises at least one metal mesh.
  14. 14. A method of preparing a thermal runaway protective film, the method comprising the steps of: (i) Compounding at least one silicate composite into a silicone resin; (ii) Forming at least one protective layer from the silicone composition obtained in step (i); and (Iii) Optionally, drying or curing the at least one protective layer obtained in step (ii), thereby obtaining a thermal runaway protective film; wherein the at least one silicate composite is contained in the at least one protective layer in an amount of at least 40 wt% based on the total weight of the at least one protective layer.
  15. 15. Use of a thermal runaway protective film according to any of claims 1 to 13 for preventing or alleviating a thermal runaway event in a lithium ion battery.

Description

Minerals to improve thermal insulation for under-hood applications for battery safety automotive electrification Technical Field The present disclosure relates to a thermal protection film for a lithium ion battery. The present disclosure also provides a method for preparing a thermal runaway protective film. In addition, the present disclosure relates to the use of a thermal runaway protective film for preventing or mitigating a thermal runaway event in a lithium ion battery. Finally, the present disclosure provides a lithium ion battery module and a lithium ion battery comprising a thermal protection film as described herein. Background Batteries based on lithium ion technology are currently the preferred solution for electric vehicles (e-mobility). Typically, a plurality of lithium ion battery cells are stacked in a row to form a battery module. In a common automotive application, the battery is made up of a plurality of modules within a housing. Such lithium ion batteries have an operating window between room temperature and about 40 ℃. Above a temperature of about 80 ℃ to 100 ℃, there is a risk of uncontrolled electrolyte decomposition followed by additional heat and pressure increase inside the cell. Eventually, the separator in the battery cell will melt and the resulting internal short circuit results in an excessive heat increase known as thermal runaway. This also results in a sudden and significant increase in the gas pressure within the cell, which may cause the cell to crack or fracture, resulting in hot gases from the cell having a temperature above 1200 ℃, which may first ignite the exterior of the cell and cause damage to surrounding cells, as a result. This situation is of course of great concern in the construction of modern electric vehicles, in particular automobiles. Recent regulations and legislation have taken this into account, requiring the minimum time that a passenger can safely leave the vehicle after a thermal runaway event. Accordingly, there is a need in the art for materials that can prevent or at least significantly slow such thermal runaway, i.e., exhibit some resistance to heat and sparging, mechanical strength, and/or are readily available and easy to manufacture, transport, and use. It is also desirable that the material be easily formed into a three-dimensional shape and also provide some thermal and electrical insulation. Disclosure of Invention The present disclosure provides a thermal runaway protective film for a lithium ion battery, the film comprising At least one protective layer comprising at least one silicone resin and at least one silicate composite in an amount of at least 40% by weight based on the total weight of the at least one protective layer. The present disclosure also provides a battery enclosure comprising a thermal runaway protective film composite construction as described herein. Further, the present disclosure provides a method for producing a thermal runaway protective film, the method comprising the steps of: (i) Compounding at least one silicate composite into a silicone resin; (ii) Forming at least one protective layer from the silicone composition obtained in step (i); and (Iii) Optionally, drying or curing the at least one protective layer obtained in step (ii), thereby obtaining a thermal runaway protective film; Wherein the at least one silicate composite is included in the at least one protective layer in an amount of at least 40 wt% based on the total weight of the at least one protective layer. Finally, the present disclosure provides the use of a thermal runaway protective film for preventing or mitigating a thermal runaway event in a lithium ion battery. Detailed Description Before any embodiments of the disclosure are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. As used herein, the terms "a," "an," and "the" are used interchangeably and mean one or more; and "and/or" is used to indicate that one or both of the described conditions may occur, e.g., a and/or B include (a and B) and (a or B). Also, herein, the recitation of ranges by endpoints includes all numbers subsumed within that range (e.g., 1 to 10 includes 1.4, 1.9, 2.33, 5.75, 9.98, etc.). Moreover, the expression "at least one" herein includes one and all numbers greater than one (e.g., at least 2, at least 4, at least 6, at least 8, at least 10, at least 25, at least 50, at least 100, etc.). Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. In contrast to the use of "consisting of" that is intended to be limiting, the use of "including," "containing," "comprising," or "having" and variations thereof is intende