Ferritic stainless steel material for battery components, method for producing same, and battery component

Abstract

This ferritic stainless steel material for battery components has a composition which contains, on a mass basis, 0.001% to 0.050% of C, 0.01% to 2.00% of Si, 0.01% to 2.00% of Mn, 0.010% to 0.050% of P, 0.0001% to 0.0100% of S, 10.0% to 30.0% of Cr and 0.001% to 0.050% of N, while additionally containing one or both of 0.01% to 0.50% of Ti and 0.01% to 0.60% of Nb, with the balance being made up of Fe and impurities. This ferritic stainless steel material for battery components contains 0.010% by volume or more of Ti-based precipitates and / or Nb-based precipitates.

Description

Ferritic stainless steel material for battery components, its manufacturing method, and battery components

[0001] The present invention relates to a ferritic stainless steel material for battery components, a manufacturing method thereof, and a battery component. More specifically, the present invention relates to a ferritic stainless steel material used for battery components of transportation equipment, a manufacturing method thereof, and a battery component comprising the ferritic stainless steel material. In this specification, "transportation equipment" refers to equipment for transporting luggage or passengers, such as automobiles, motorcycles, tricycles, bicycles, buses, and railcars. Furthermore, "battery components" refers to components that constitute a battery, such as a battery case, battery pack, battery module, and battery cover.

[0002] In recent years, improving the fuel efficiency of transportation equipment has become an essential issue from the perspective of environmental issues. As one solution to this issue, active efforts are being made to reduce the weight of transportation equipment bodies. Weight reduction of vehicle bodies is largely achieved by reducing the weight of the materials used in the parts that make up the body, for example, by reducing the thickness of the material. However, reducing the thickness of the material reduces the rigidity and crash absorption performance of the parts. Increasing the strength of the materials that make up the parts is an effective countermeasure, and high-strength ordinary steel (high-tensile steel) is used.

[0003] However, because ordinary steel has poor corrosion resistance, it is assumed to be heavily painted. Therefore, ordinary steel cannot be used on unpainted or lightly painted parts, and heavy painting increases costs. Furthermore, ordinary steel also has poor heat resistance, making it unable to withstand thermal runaway, which can occur in battery components. Here, "thermal runaway" refers to a phenomenon in which heat inside a battery becomes uncontrollable for some reason, resulting in abnormal heat generation and, in some cases, fire. On the other hand, stainless steel materials containing Cr have superior corrosion resistance compared to ordinary steel, which is expected to reduce rust allowance (thickness to allow for rust) and enable weight reduction and the elimination of painting. Furthermore, stainless steel materials have superior heat resistance compared to ordinary steel, making them resistant to thermal runaway. Therefore, safety can be improved by suppressing ignition and fire spread. Therefore, the use of stainless steel materials offers significant benefits, such as improved fuel efficiency due to reduced vehicle weight, simplified painting, and improved safety.

[0004] In the field of transportation equipment, such as automobiles, powertrains are becoming increasingly diverse, with electric vehicles and fuel cell vehicles, which do not have internal combustion engines, being put into practical use in addition to internal combustion engine vehicles, diesel vehicles, and hybrid vehicles. Electric vehicles, in particular, are equipped with large-capacity batteries and run on motors, and are equipped with many battery components. Since electric vehicles are equipped with multiple batteries, if one battery experiences thermal runaway, it is likely that the other batteries will also experience thermal runaway in a chain reaction, potentially leading to a vehicle fire.

[0005] Materials used for battery components include stainless steel, aluminum, resin, and Ni-plated steel. For example, Patent Document 1 discloses a method for manufacturing a lithium-ion secondary battery case using austenitic stainless steel foil as a stainless steel material for battery components. Patent Document 2 discloses the application of an austenitic stainless steel sheet to a battery case for an electric vehicle with excellent heat resistance. Patent Document 3 discloses a ferritic stainless steel containing 16.0 to 32.0 mass% Cr as an electrode material and electrode case for a large-capacity battery. However, the stainless steel materials disclosed in Patent Documents 1 to 3 lack sufficient impact absorption properties (impact resistance) when used for battery components. Therefore, when a battery is subjected to an impact due to a collision or other accident, the battery is easily damaged, causing a short circuit within the battery and resulting in thermal runaway.

[0006] On the other hand, as a technology for suppressing thermal runaway of batteries due to impact, Patent Document 4 proposes a technology in which an insulating layer is provided on a laminate seal that constitutes a secondary battery case. Patent Documents 5 to 7 also propose a technology for suppressing thermal runaway of batteries by providing a member made of mica on battery components. However, these technologies have the problem that they cannot suppress damage to battery components, and the installation of insulating layers and mica leads to increased costs. Furthermore, these technologies do not improve the impact absorption properties of stainless steel materials, making it difficult to reduce the thickness of battery components.

[0007] Japanese Patent No. 6090923 Publication No. JP-A-10-188922 Publication No. JP-A-2009-167486 Publication No. JP-A-6522736 Publication No. JP-A-2022-522369 Publication No. WO 2019 / 150771 Publication No. JP-A-6631726

[0008] As described above, there are no materials that not only protect the battery but also have excellent resistance to thermal runaway when the battery is subjected to an impact due to a collision accident, etc. Under these circumstances, an object of the present invention is to provide a ferritic stainless steel material for battery components that has excellent battery protection performance and excellent resistance to thermal runaway when the battery is subjected to an impact due to a collision accident, etc., a method for manufacturing the same, and a battery component.

[0009] As a result of extensive research, the present inventors have found that a ferritic stainless steel material with a controlled composition and amount of predetermined precipitates can solve the above problems. Furthermore, the present inventors have found that a ferritic stainless steel material with such characteristics can be obtained by annealing and cooling a cold-rolled material with a predetermined composition under specific conditions. The present invention was completed based on these findings.

[0010] That is, the present invention provides a ferritic stainless steel material for battery components, which contains, by mass, C: 0.001 to 0.050%, Si: 0.01 to 2.00%, Mn: 0.01 to 2.00%, P: 0.010 to 0.050%, S: 0.0001 to 0.0100%, Cr: 10.0 to 30.0%, N: 0.001 to 0.050%, and further contains one or two selected from Ti: 0.01 to 0.50% and Nb: 0.01 to 0.60%, with the balance consisting of Fe and impurities, and contains 0.010 vol% or more of Ti-based precipitates and / or Nb-based precipitates.

[0011] The present invention also provides a method for producing a ferritic stainless steel material for battery components, which comprises, on a mass basis, C: 0.001 to 0.050%, Si: 0.01 to 2.00%, Mn: 0.01 to 2.00%, P: 0.010 to 0.050%, S: 0.0001 to 0.0100%, Cr: 10.0 to 30.0%, N: 0.001 to 0.050%, and further contains one or two selected from Ti: 0.01 to 0.50% and Nb: 0.01 to 0.60%, with the balance being Fe and impurities. The method comprises annealing the cold-rolled material at 850 to 1050°C, and then cooling it to 800°C at a cooling rate of 10°C / second or less.

[0012] Furthermore, the present invention is a battery component comprising a ferritic stainless steel material for a battery component.

[0013] According to the present invention, it is possible to provide a ferritic stainless steel material for battery components that has excellent battery protection performance and resistance to thermal runaway when the battery is subjected to an impact due to a collision accident or the like, a method for manufacturing the same, and a battery component.

[0014] A 10% comparison of a ferritic stainless steel material containing 0.010% by volume of Ti-based precipitates and / or Nb-based precipitates and a ferritic stainless steel material not containing Ti-based precipitates and / or Nb-based precipitates 3 1 is a graph showing the relationship between strain and flow stress when a tensile test was conducted at a strain rate of 1 / sec.

[0015] In order to ensure the battery's protection performance when an impact is applied to the battery due to a collision accident or the like, it is necessary to improve the impact absorption characteristics (impact resistance) during high-speed deformation of the ferritic stainless steel material that is the material for the battery components. Also, in order to ensure resistance to thermal runaway, it is necessary to improve the high-temperature rigidity of the ferritic stainless steel material. In the present invention, the impact absorption characteristics during high-speed deformation are evaluated by assuming an impact due to a collision accident or the like. 3 Various ferritic stainless steel materials were prepared and analyzed in detail using the flow stress at 10% strain in a tensile test conducted at a strain rate of 1 / sec, and the Young's modulus at 900°C as an evaluation of high-temperature rigidity. As a result, it was found that by controlling the composition of the ferritic stainless steel material and the amount of predetermined precipitates, it is possible to improve the impact absorption characteristics during high-speed deformation and the high-temperature rigidity, which led to the completion of the present invention.

[0016] The embodiments of the present invention, which have been completed based on the above-mentioned viewpoints, are described in detail below. The present invention is not limited to the following embodiments, and it should be understood that modifications and improvements to the following embodiments, as appropriate, based on the ordinary knowledge of those skilled in the art, without departing from the spirit of the present invention, also fall within the scope of the present invention. In this specification, the "%" designation for components means "% by mass" unless otherwise specified.

[0017] (1) Ferritic Stainless Steel Material for Battery Components A ferritic stainless steel material for battery components according to an embodiment of the present invention (hereinafter sometimes abbreviated as "ferritic stainless steel material") contains C: 0.001 to 0.050%, Si: 0.01 to 2.00%, Mn: 0.01 to 2.00%, P: 0.010 to 0.050%, S: 0.0001 to 0.0100%, Cr: 10.0 to 30.0%, N: 0.001 to 0.050%, and further contains one or two selected from Ti: 0.01 to 0.50% and Nb: 0.01 to 0.60%, with the balance being Fe and impurities.

[0018] Here, in this specification, "impurities" refers to components that are mixed in during the industrial production of ferritic stainless steel materials due to raw materials such as ores and scraps, or various factors in the manufacturing process, and are acceptable within a range that does not adversely affect the present invention. For example, impurities include unavoidable impurities. Examples of impurities include O, As, and Pb. It is preferable to reduce impurities as much as possible. Furthermore, in this specification, "stainless steel material" refers to a material formed from stainless steel, and its shape is not particularly limited. Examples of the shape include plate (including strip), rod, and tube. In addition, various types of sectional shapes such as T-shaped and I-shaped steel are also acceptable.

[0019] Furthermore, in this specification, "ferritic" refers to a metal structure that is primarily ferrite at room temperature. Therefore, "ferritic" also includes those that contain small amounts of phases other than ferrite (e.g., austenite or martensite). However, "ferritic" does not include a multi-phase structure of ferrite and austenite, a multi-phase structure of ferrite and martensite, or a multi-phase structure of ferrite, austenite, and martensite. Stainless steel materials with these multi-phase structures have high strength, but are insufficient in shock absorption properties (flow stress during high-speed deformation) and workability during high-speed deformation.

[0020] Furthermore, the ferritic stainless steel material according to an embodiment of the present invention contains Ni: 0.01 to 2.00%, Al: 0.001 to 1.000%, Cu: 0.01 to 2.00%, Mo: 0.01 to 3.00%, V: 0.01 to 0.50%, Zr: 0.01 to 0.50%, B: 0.0002 to 0.0050%, Ca: 0.0005 to 0.0100%, W: 0.10 to 3.00%, Sn: 0. It may further contain one or more selected from: 0.01 to 0.50%, Co: 0.03 to 0.30%, Mg: 0.0002 to 0.0100%, Sb: 0.005 to 0.300%, REM: 0.002 to 0.200%, Ga: 0.0002 to 0.3000%, Ta: 0.001 to 1.000%, Hf: 0.001 to 1.000%, and Bi: 0.001 to 0.020%. Each component will be described in detail below.

[0021] <C: 0.001 to 0.050%> Since C is an element that reduces corrosion resistance and heat resistance, the C content is set to 0.050% or less. However, since excessive reduction of C leads to increased refining costs, the lower limit of the C content is set to 0.001%. Furthermore, from the viewpoint of impact absorption characteristics during high-speed deformation (flow stress during high-speed deformation), the lower limit of the C content is preferably 0.003% or more. Furthermore, from the viewpoint of weldability, the upper limit of the C content is preferably 0.010% or less. Furthermore, in consideration of manufacturability and workability, the C content is more preferably 0.003 to 0.008%.

[0022] <Si: 0.01 to 2.00%> Si is a deoxidizing element. Furthermore, Si is a solid-solution strengthening element and is effective in improving impact absorption characteristics (flow stress during high-speed deformation) during high-speed deformation, so the Si content is set to 0.01% or more. However, since excessive addition of Si leads to a rapid decrease in ductility, the upper limit of the Si content is set to 2.00%. Furthermore, in consideration of corrosion resistance and manufacturability, the Si content is preferably 0.05 to 0.90%. Furthermore, in consideration of weldability and toughness, the Si content is more preferably 0.10 to 0.40%.

[0023] <Mn: 0.01 to 2.00%> Mn is a deoxidizing element. Furthermore, Mn is a solid-solution strengthening element and is effective in improving impact absorption characteristics (flow stress during high-speed deformation) during high-speed deformation. Therefore, the Mn content is set to 0.01% or more. However, since excessive addition of Mn leads to a decrease in corrosion resistance, the upper limit of the Mn content is set to 2.00%. Furthermore, in consideration of oxidation resistance and strength, the Mn content is preferably 0.10 to 1.00%. Furthermore, in consideration of manufacturability and weldability, the Mn content is more preferably 0.20 to 0.50%.

[0024] <P: 0.010 to 0.050%> P reduces workability, corrosion resistance, manufacturability, etc., so the lower the content, the better. If the P content is too high, coarse phosphides are formed, which become the starting point for void formation during high-speed deformation, so the upper limit of the P content is set to 0.050%. On the other hand, the formation of fine FeTiP or FeNbP leads to improved shock absorption characteristics during high-speed deformation (flow stress during high-speed deformation), so the lower limit of the P content is set to 0.010%. Furthermore, considering refining costs and workability, the P content is preferably 0.020 to 0.030%.

[0025] <S: 0.0001 to 0.0100%> S reduces workability, corrosion resistance, manufacturability, and the like, so the lower the content, the better. If the S content is too high, coarse sulfides are formed, which become the starting point for void formation during high-speed deformation, so the upper limit of the S content is set to 0.0100%. On the other hand, the formation of fine TiS and Ti4C2S2 leads to improved shock absorption characteristics during high-speed deformation (flow stress during high-speed deformation), so the lower limit of the S content is set to 0.0001%. Furthermore, considering refining costs and weldability, the S content is preferably 0.0005 to 0.0020%.

[0026] <Cr: 10.0 to 30.0%> Cr is an element added to improve corrosion resistance and heat resistance. In particular, the Cr content is set to 10.0% or more to eliminate painting and improve high-temperature rigidity. On the other hand, if the Cr content is too high, toughness decreases significantly, so the upper limit of the Cr content is set to 30.0%. Furthermore, taking into consideration manufacturability, cost, corrosion resistance of welded parts, and impact absorption characteristics during high-speed deformation, the Cr content is preferably 11.0 to 18.0%.

[0027] <N: 0.001 to 0.050%> N is an element that reduces corrosion resistance and heat resistance, so the N content is set to 0.050% or less. However, since excessive reduction of N leads to increased refining costs, the lower limit of the N content is set to 0.001%. Furthermore, from the viewpoint of impact absorption characteristics during high-speed deformation, the lower limit of the N content is preferably 0.003% or more. Furthermore, from the viewpoint of weldability, the upper limit of the N content is preferably 0.010% or less. Furthermore, in consideration of manufacturability and workability, the N content is more preferably 0.003 to 0.008%.

[0028] <One or two selected from Ti: 0.01 to 0.50% and Nb: 0.01 to 0.60%> Ti and Nb bond with C and N to suppress the formation of coarse Cr carbonitrides, thereby preventing intergranular corrosion. They also promote the development of {111} texture, contributing to improved workability (e.g., deep drawability). Ti and Nb are also elements necessary for producing Ti-based precipitates and Nb-based precipitates, which are effective in improving shock absorption characteristics (flow stress during high-speed deformation) during high-speed deformation. Here, in this specification, "Ti-based precipitates and Nb-based precipitates" refers to Ti and Nb carbides and nitrides, as well as phosphides (FeTiP, FeNbP) and sulfides (TiS, TiC2S2). In order to generate predetermined amounts of Ti-based precipitates and Nb-based precipitates in a ferritic stainless steel material, the Ti content is set to 0.01% or more and the Nb content is set to 0.01% or more. However, excessive addition of Ti and Nb causes the Ti-based precipitates and Nb-based precipitates to become excessively coarse, resulting in a decrease in toughness. Therefore, the upper limit of the Ti content is set to 0.50%, and the upper limit of the Nb content is set to 0.60%. Furthermore, from the viewpoints of workability, manufacturability, and cost, the Ti content and Nb content are preferably both 0.05 to 0.30% or less. Furthermore, from the viewpoint of manufacturing cost, the Ti content and Nb content are more preferably both 0.05 to 0.20%.

[0029] <Ni: 0.01 to 2.00%> Ni is an element that contributes to high strength and is effective in improving impact absorption characteristics (flow stress during high-speed deformation) during high-speed deformation, and is added in an amount of 0.01% or more as needed. However, excessive addition of Ni reduces high-temperature rigidity (high-temperature Young's modulus), increases component costs, and reduces formability by generating austenite and martensite phases, so the upper limit of the Ni content is set to 2.00%. Furthermore, in consideration of toughness and corrosion resistance, the Ni content is preferably 0.10 to 1.00%. Furthermore, in consideration of heat resistance, the Ni content is more preferably 0.20 to 0.50%.

[0030] <Al: 0.001 to 1.000%> Al is an element added as a deoxidizing element. To efficiently exert this effect, 0.001% or more is added as needed. Al is also an element that is effective in improving workability by forming nitrides, increasing strength through solid solution strengthening, and improving oxidation resistance. However, excessive addition of Al leads to reduced high-temperature rigidity, the occurrence of surface defects, reduced weldability, and reduced ductility due to coarse AlN. Therefore, the upper limit of the Al content is set to 1.000%. Furthermore, in consideration of deoxidation efficiency and toughness, the Al content is preferably 0.020 to 0.500%. Furthermore, in consideration of weldability, the Al content is more preferably 0.020 to less than 0.100%.

[0031] <Cu: 0.01 to 2.00%> Cu contributes to improving corrosion resistance and improving high-temperature rigidity and strength through the precipitation of ε-Cu, and is added in an amount of 0.01% or more as necessary. However, since an excessively high Cu content significantly reduces ductility, the upper limit of the Cu content is set to 2.00%. Furthermore, in consideration of oxidation resistance and component costs, the Cu content is preferably 0.05 to 1.50%. Furthermore, in consideration of toughness and weldability, the Cu content is more preferably 0.10 to 0.50%.

[0032] <Mo: 0.01 to 3.00%> Mo is an element that improves corrosion resistance. Furthermore, Mo is a solid-solution strengthening element and is effective in improving impact absorption characteristics (flow stress during high-speed deformation) during high-speed deformation. Therefore, Mo is added in an amount of 0.01% or more as needed. However, excessive addition of Mo not only reduces workability and increases costs, but also significantly reduces toughness, so the upper limit of the Mo content is set to 3.00%. Furthermore, from the viewpoints of high-temperature rigidity and oxidation resistance, the Mo content is preferably 0.10 to 1.50%. Furthermore, from the viewpoint of cost reduction, the Mo content is more preferably 0.10 to 1.20%.

[0033] <V: 0.01 to 0.50%, Zr: 0.01 to 0.50%> Like Ti and Nb, V and Zr are elements that bond with C and N and suppress the formation of coarse Cr carbonitrides. V and Zr are also effective elements for generating fine precipitates (Zr(C,N), V(C,N)) that improve the impact absorption characteristics (flow stress during high-speed deformation) during high-speed deformation. Therefore, V and Zr are each added in an amount of 0.01% or more as needed. However, excessive addition of V and Zr reduces toughness and high-temperature rigidity, so the upper limits of the V content and Zr content are both set to 0.50%. From the viewpoint of formability, the V content and Zr content are both preferably 0.05 to 0.30%. Furthermore, considering the impact absorption characteristics and bendability of welds during high-speed deformation, the V content and Zr content are more preferably 0.1 to 0.2%.

[0034] <B: 0.0002 to 0.0050%> B is an element that is effective in increasing strength and also suppressing secondary processing cracking. Furthermore, B forms borides, which can be effective in improving impact absorption characteristics (flow stress during high-speed deformation) during high-speed deformation. Therefore, B is added in an amount of 0.0002% or more as needed. However, excessive addition of B can cause void formation and reduce formability and toughness, so the upper limit of the B content is set to 0.0050%. Furthermore, in consideration of corrosion resistance, the B content is preferably 0.0002 to 0.0020%. Furthermore, in consideration of weldability, the B content is more preferably 0.0005 to 0.0010%.

[0035] <Ca: 0.0005 to 0.0100%> Ca is added in an amount of 0.0005% or more as needed to fix S and improve hot workability. However, excessive addition of Ca not only reduces corrosion resistance but also reduces ductility during high-speed deformation due to coarse CaS. Therefore, the upper limit of the Ca content is set to 0.0100%. Furthermore, from the viewpoint of manufacturability, the Ca content is preferably 0.0005 to 0.0010%.

[0036] <W: 0.10 to 3.00%> W is an element that improves corrosion resistance and also functions as a solid-solution strengthening element. Therefore, 0.10% or more is added depending on the corrosion resistance level required in the usage environment. However, excessive addition of W leads to a decrease in workability and toughness and an increase in cost, so the upper limit of the W content is set to 3.00%. The W content is preferably 0.10 to 1.50%.

[0037] <Sn: 0.01 to 0.50%> Sn contributes to improving corrosion resistance and high-temperature strength, so 0.01% or more is added as necessary. However, excessive addition of Sn may cause slab cracking during manufacturing, and grain boundary cracking during processing (for example, hole expansion) becomes more pronounced. Therefore, the upper limit of the Sn content is set to 0.50%. Furthermore, considering refining costs and manufacturability, the Sn content is preferably 0.01 to 0.30%.

[0038] <Co: 0.03 to 0.30%> Co contributes to improving high-temperature strength, so 0.03% or more is added as necessary. However, excessive addition of Co leads to reduced toughness during manufacturing, increased costs, and reduced workability (e.g., reduced hole expandability). Therefore, the upper limit of the Co content is set to 0.30%. Furthermore, considering refining costs and manufacturability, the Co content is preferably 0.03 to 0.10%.

[0039] <Mg: 0.0002 to 0.0100%> Mg is an element added as a deoxidizing element. Furthermore, Mg contributes to improving manufacturability by refining ferrite grains, improving surface defects known as ridging, and improving the workability of welds. To achieve these effects, the Mg content is set to 0.0002% or more. However, excessive addition of Mg significantly reduces corrosion resistance and also reduces workability (e.g., hole expandability) due to coarse MgO. Therefore, the upper limit of the Mg content is set to 0.0100%. Considering manufacturability, the Mg content is preferably 0.0002 to 0.0020%.

[0040] <Sb: 0.005 to 0.300%> Sb is an element that segregates at grain boundaries and has the effect of increasing high-temperature strength. To obtain this effect of Sb addition, the Sb content is set to 0.005% or more. However, excessive addition of Sb may cause grain boundary cracking during processing (e.g., hole expansion) and cracking during welding due to Sb segregation, so the upper limit of the Sb content is set to 0.300%. In consideration of high-temperature properties, manufacturing costs, and toughness, the Sb content is preferably 0.030 to 0.200%, and more preferably 0.050 to 0.100%.

[0041] <REM: 0.002-0.200%> REM (rare earth elements) are effective in improving oxidation resistance and are added at 0.002% or more as needed. However, excessive REM addition saturates its effect and reduces corrosion resistance and hole expandability due to REM granulation, so the upper limit of the REM content is set to 0.200%. Considering workability and manufacturing costs, a REM content of 0.002-0.100% is preferred. Note that REM follows the general definition. That is, REM refers to two elements, scandium (Sc) and yttrium (Y), and 15 elements (lanthanoids) ranging from lanthanum (La) to lutetium (Lu). REM may be added alone or in mixtures.

[0042] <Ga: 0.0002 to 0.3000%> Ga is an element added as needed to improve corrosion resistance and suppress hydrogen embrittlement. In particular, from the viewpoint of forming sulfides and hydrides that are effective in achieving these effects, the lower limit of the Ga content is set to 0.0002%. Furthermore, from the viewpoints of manufacturability and cost, the Ga content is preferably 0.0020% or more. However, excessive addition of Ga can cause the formation of coarse sulfides, which reduces workability (for example, hole expandability), so the upper limit of the Ga content is set to 0.3000%.

[0043] <Ta: 0.001 to 1.000%, Hf: 0.001 to 1.000%> Ta and Hf are elements effective in improving high-temperature strength and are added as needed. To achieve such effects, the Ta content and Hf content are both set to 0.001 to 1.000%. From the viewpoint of improving high-temperature strength, the Ta content and Hf content are preferably 0.100% or less, and more preferably 0.010% or less.

[0044] <Bi: 0.001 to 0.020%> Bi is an element effective in improving machinability and is added as needed. To achieve this effect, the Bi content is set to 0.001 to 0.020%. From the viewpoint of improving machinability, the Bi content is preferably 0.015% or less.

[0045] The ferritic stainless steel material according to the embodiment of the present invention contains 0.010 vol% or more of Ti-based precipitates and / or Nb-based precipitates. That is, the ferritic stainless steel material according to the embodiment of the present invention may have a Ti-based precipitate amount of 0.010 vol% or more, a Nb-based precipitate amount of 0.010 vol% or more, or a total amount of Ti-based precipitates and Nb-based precipitates of 0.010 vol% or more. By controlling the amount of Ti-based precipitates and / or Nb-based precipitates within such ranges, the impact absorption characteristics during high-speed deformation and high-temperature rigidity can be improved. On the other hand, although there is no particular upper limit for the amount of Ti-based precipitates and / or Nb-based precipitates, if the amount is too large, voids may be formed, resulting in molding defects. From the viewpoint of suppressing this problem, the amount of Ti-based precipitates and / or Nb-based precipitates is preferably 0.200 vol% or less. Furthermore, in consideration of low temperature toughness and weldability, the amount of Ti-based precipitates and / or Nb-based precipitates is more preferably 0.020 to 0.100% by volume.

[0046] The amount of Ti-based precipitates and / or Nb-based precipitates in a ferritic stainless steel material can be determined by observing a cross section of the ferritic stainless steel material under a microscope and determining the area ratio of the area where Ti-based precipitates and / or Nb-based precipitates exist to the entire structure in accordance with the point counting method specified in JIS G0555:2003.

[0047] The particle size of the Ti-based precipitates and / or Nb-based precipitates is not particularly limited, but is preferably 10 μm or less, more preferably 9 μm or less. By controlling the particle size of the Ti-based precipitates and / or Nb-based precipitates within this range, it is possible to improve the impact absorption characteristics during high-speed deformation and high-temperature rigidity, as well as corrosion resistance by suppressing void formation during forming. The lower limit of the particle size of the Ti-based precipitates and / or Nb-based precipitates is not particularly limited, but is typically 0.1 μm, preferably 1 μm. The particle size of the Ti-based precipitates and / or Nb-based precipitates can be measured by observing the cross section of the ferritic stainless steel material with a scanning electron microscope. The particle size of the Ti-based precipitates and / or Nb-based precipitates is determined as the diameter of a circle having the same area.

[0048] The ferritic stainless steel material according to the embodiment of the present invention is 10 3 It is preferable that the flow stress at 10% strain when a tensile test is carried out at a strain rate of 10 / sec is 500 MPa or more. 3 The flow stress at 10% strain when a tensile test is performed at a strain rate of 1 / s is an index representing the impact absorption characteristics during high-speed deformation, assuming an impact due to a collision accident or the like. If this flow stress is 500 MPa or more, it can be said that the impact absorption characteristics during high-speed deformation are excellent and that the crash safety of battery components in general automobiles can be ensured. Considering the weight reduction achieved by reducing the thickness of battery components made of ferritic stainless steel, this flow stress is more preferably 550 MPa or more, and even more preferably 600 MPa or more.

[0049] Here, as an example, a ferritic stainless steel material containing 0.010% by volume of Ti-based precipitates and / or Nb-based precipitates (referred to as an "invention example") and a ferritic stainless steel material not containing Ti-based precipitates and / or Nb-based precipitates (referred to as a "comparison example") were compared. 3 The results of the tensile test conducted at a strain rate of 10 / sec are shown in Figure 1. Figure 1 is a graph showing the relationship between strain (x-axis) and flow stress (y-axis). The ferritic stainless steel materials of the invention examples and comparative examples both had a composition containing 17% Cr-0.01% C-0.01% N. As shown in Figure 1, the invention examples had a high flow stress of 500 MPa or more at 10% strain, and were excellent in shock absorption properties during high-speed deformation, whereas the comparative examples had a flow stress of less than 500 MPa at 10% strain. This is because the strain rate of the comparative examples is 10% at 10% strain, which is the same as that of collision accidents. 3 This indicates that when the flow rate is extremely high, such as 1 / sec, the presence of Ti-based precipitates and / or Nb-based precipitates effectively hinders the movement of dislocations, leading to an increase in flow stress.

[0050] The ferritic stainless steel material according to the embodiment of the present invention preferably has a Young's modulus at 900°C of 80 GPa or more. Here, the Young's modulus at 900°C is an index of high-temperature rigidity. In the event of a collision or other accident, the interior of the destroyed battery instantaneously reaches a high temperature of approximately 900°C, exposing other battery components constituting the battery to high temperatures. If the Young's modulus at 900°C is less than 80 GPa, the battery components will deform and thermal runaway will be more likely to occur. On the other hand, if the Young's modulus at 900°C is 80 GPa or more, deformation of the battery components can be suppressed, and thermal runaway can be suppressed. Considering the weight reduction achieved by reducing the thickness of battery components made of ferritic stainless steel, the Young's modulus at 900°C is more preferably 90 GPa or more. Since a higher Young's modulus at 900°C indicates better high-temperature rigidity, the upper limit is not particularly limited, but is, for example, 200 GPa, and generally 150 GPa. The Young's modulus at 900° C. can be determined by the resonance method in accordance with the method specified in JIS Z2280:1993.

[0051] The ferritic stainless steel material according to the embodiment of the present invention preferably has a breaking elongation of 30% or more at room temperature (25°C). Here, the breaking elongation at room temperature is an index of workability. By ensuring that the breaking elongation at room temperature is 30% or more, workability into battery components having various shapes is ensured. The upper limit of the breaking elongation at room temperature is not particularly limited, but is, for example, 50%. The breaking elongation at room temperature can be determined by conducting a tensile test in accordance with JIS Z2241:2011 using a JIS No. 13B test piece taken so that the rolling direction of the ferritic stainless steel material is parallel to the parallel portion.

[0052] The ferritic stainless steel material according to the embodiment of the present invention preferably has a maximum pitting depth of less than 200 μm. Here, the maximum pitting depth is an index representing corrosion resistance. By making the maximum pitting depth less than 200 μm, it can be said that the corrosion resistance is excellent. The maximum pitting depth can be determined by subjecting the ferritic stainless steel material to 30 cycles of JASO-CCT testing, subjecting the material to rust removal treatment, and then measuring by a focal depth method using a microscope.

[0053] The thickness of the ferritic stainless steel material according to the embodiments of the present invention is not particularly limited and may be appropriately set depending on the characteristics of the product in which the ferritic stainless steel material is used. For example, considering the weight reduction of the ferritic stainless steel material and battery components formed therefrom, the thickness of the ferritic stainless steel material is preferably 1.0 mm or less. Furthermore, considering the rigidity of the ferritic stainless steel material and battery components formed therefrom, the thickness of the ferritic stainless steel material is more preferably 0.1 mm or more. Furthermore, considering the fire resistance and cost of the ferritic stainless steel material and battery components formed therefrom, the thickness of the ferritic stainless steel material is even more preferably 0.2 to 0.8 mm. Furthermore, considering the weldability of the ferritic stainless steel material and battery components formed therefrom, the thickness of the ferritic stainless steel material is even more preferably 0.3 to 0.6 mm.

[0054] The ferritic stainless steel material according to the embodiment of the present invention, with its composition and the amount of predetermined precipitates controlled as described above, has excellent impact absorption properties during high-speed deformation and high-temperature rigidity. Therefore, the ferritic stainless steel material according to the embodiment of the present invention has excellent battery protection performance and resistance to thermal runaway when the battery is subjected to an impact, such as in a collision accident. Furthermore, the ferritic stainless steel material according to the embodiment of the present invention contributes to reducing the cost of battery components because it eliminates the need for the formation of an insulating layer or the application of mica, which were required in conventional technologies to suppress thermal runaway in batteries due to impact. In other words, by using the ferritic stainless steel material according to the embodiment of the present invention as a material for battery components in transportation equipment (particularly automobiles, buses, trains, etc.), environmental measures such as weight reduction, improved collision safety, measures against thermal runaway, and cost reduction can be achieved.

[0055] (2) Manufacturing Method of Ferritic Stainless Steel Material for Battery Components The manufacturing method of the ferritic stainless steel material according to the embodiment of the present invention is not particularly limited as long as it is a method capable of manufacturing a ferritic stainless steel material having the above-described characteristics. For example, the manufacturing method of the ferritic stainless steel material according to the embodiment of the present invention is carried out by annealing a cold-rolled material having the above-described composition at 850 to 1050°C, and then cooling it to 800°C at a cooling rate of 10°C / sec or less. By controlling the conditions in this manner, a ferritic stainless steel material having the above-described characteristics can be manufactured. Note that, after annealing and cooling as described above, pickling treatment may be performed as necessary. Details of the manufacturing method are described below.

[0056] The cold-rolled material can be produced by a conventional method. Specifically, first, stainless steel having the above-mentioned composition is melted and forged or cast, and then hot-rolled to obtain a hot-rolled material. The hot-rolled material is then annealed, pickled, and cold-rolled in sequence to obtain a cold-rolled material. Here, each step can be carried out using existing equipment, and the conditions can be adjusted appropriately depending on the composition of the stainless steel, and are not particularly limited. Furthermore, existing treatments (e.g., surface polishing, temper rolling, treatment using a tension leveler, etc.) may be carried out as necessary.

[0057] The cold-rolled material obtained as described above is annealed at 850 to 1050°C. By annealing within this temperature range, a recrystallized structure can be obtained. In particular, from the viewpoints of workability and toughness, the annealing temperature is preferably 880 to 1000°C. By annealing within this temperature range, the grain size number specified in JIS G0551:2013 can be controlled to 5 to 9, preferably 6 to 8. Note that annealing can be carried out in a conventional annealing apparatus, such as a continuous annealing line.

[0058] The cold-rolled material after annealing is usually cooled by air-cooling. In order to generate 0.010 volume % or more of Ti-based precipitates and / or Nb-based precipitates (hereinafter, abbreviated as "precipitates") during the cooling process, the cooling rate to 800°C is set to 10°C / sec or less. Cooling under such conditions can promote the precipitation of precipitates. There is no particular limitation on the lower limit of this cooling rate, but if it is too slow, the precipitates may become too coarse, resulting in a deterioration of toughness. Therefore, it is preferable to set the lower limit of this cooling rate to 3°C / sec. Furthermore, considering productivity and the shape of the steel material, the cooling rate is more preferably 4 to 8°C / sec.

[0059] The annealed cold-rolled material cooled to 800°C is preferably cooled to 400°C (i.e., the temperature range from 800°C to 400°C) at a cooling rate of more than 10°C / s, more preferably at 12°C / s or more, and even more preferably at 15°C / s or more. This is because if the cooling rate is 10°C / s or less in this temperature range, intermetallic compounds such as Laves phases and σ phases, which significantly reduce low-temperature toughness, are formed. The upper limit of this cooling rate is not particularly limited, but if it is too fast, the shape of the steel material may be significantly deteriorated. Therefore, it is preferable to set the upper limit of this cooling rate to 100°C / s. Furthermore, considering the pickling properties in the subsequent process and the shape of the steel material, the cooling rate is particularly preferably 20 to 80°C / s.

[0060] (3) Battery Components Battery components according to embodiments of the present invention include the above-described ferritic stainless steel material. The above-described ferritic stainless steel material has excellent shock absorption properties during high-speed deformation and high-temperature rigidity, so that this battery component has excellent battery protection performance and resistance to thermal runaway when the battery is subjected to an impact due to a collision accident, etc. Examples of battery components include, but are not limited to, battery cases, battery packs, battery modules, and battery covers.

[0061] The present invention will be described in detail below with reference to examples, but the present invention should not be construed as being limited thereto. Ferritic stainless steel sheets were produced according to the following procedure. Stainless steel having the composition shown in Tables 1 and 2 was melted and hot-rolled to obtain a hot-rolled sheet having a thickness of 3.8 mm, which was then pickled to obtain a hot-rolled, pickled sheet. The hot-rolled, pickled sheet was then cold-rolled to obtain a cold-rolled sheet having a thickness of 0.6 mm. The cold-rolled sheet was then annealed and cooled under the conditions shown in Tables 3 and 4, and then pickled to obtain a cold-rolled, annealed sheet (ferritic stainless steel sheet).

[0062]

[0063]

[0064]

[0065]

[0066] The cold-rolled and annealed sheets obtained above were subjected to the following evaluations.

[0067] <Amount of Ti-based precipitates and / or Nb-based precipitates (hereinafter, abbreviated as "precipitates")> According to the point counting method specified in JIS G0555:2003, the cross section of the cold-rolled annealed sheet was observed under a microscope, and the amount of precipitates was determined from the area ratio of the precipitate presence region to the entire structure. Specifically, the cold-rolled annealed sheet was filled with resin so that the thickness direction cross section parallel to the rolling direction became the observation surface, and then mirror polished. Then, inclusions at 1 / 4 to 3 / 4 of the thickness were observed at 400x magnification using an optical microscope. At this time, 60 fields of view were observed using an optical microscope with a 20 x 20 grid attached to the measuring lens, and the inclusions covering the grid were counted to calculate the area ratio, which was defined as the amount of precipitates (volume%).

[0068] <Grain size of precipitates> The grain size of precipitates was determined by filling the cold-rolled annealed sheet with resin so that the thickness cross section parallel to the rolling direction served as the observation surface, mirror polishing the sheet, and then observing the precipitates at 1 / 4 to 3 / 4 of the thickness at a magnification of 3000x using a scanning electron microscope. Observation was performed in 10 fields of view, and the area of ​​the largest precipitate was calculated, and the equivalent circle diameter was determined to be the grain size of the precipitate. Note that precipitates were analyzed by EDS attached to the scanning electron microscope, and were determined to be precipitates if the Ti and / or Nb content of the precipitate was equal to or greater than the content in the base material.

[0069] <10 3 Flow stress at 10% strain when tensile test was performed at a strain rate of 10 / s > Tensile test specimens with a parallel width of 2.0 mm and a gauge length of 4.8 mm were taken from the cold-rolled annealed sheet so that the tensile direction was the rolling direction, and a high-speed tensile test was performed. The high-speed tensile test was performed using a high-speed tensile tester (a sensing block type high-speed tensile tester manufactured by Saginomiya Seisakusho Co., Ltd.) at a strain rate of 10 3 The flow stress at 10% strain was calculated from the relationship between the flow stress and strain.

[0070] <Young's modulus at 900°C> The Young's modulus at 900°C was determined by a resonance method in accordance with the method specified in JIS Z2280: 1993. Specifically, a measurement specimen having a length of 60 mm in the rolling direction and a width of 10 mm was taken from the cold-rolled annealed sheet, and measured at 900°C by a resonance method using an elastic modulus measuring device (EG-HT elastic modulus measuring device manufactured by Nippon Technoplus Co., Ltd.).

[0071] <Fracture elongation at room temperature> Using a JIS No. 13B test piece taken from a cold-rolled annealed sheet so that the rolling direction was parallel to the parallel portion, a tensile test was performed at room temperature (25°C) in accordance with JIS Z2241:2011 using a tensile tester (precision universal testing machine Autograph AG-X manufactured by Shimadzu Corporation).

[0072] <Corrosion Resistance (Maximum Pit Depth)> Measurement specimens measuring 150 mm in the rolling direction and 75 mm in the width direction were taken from the cold-rolled annealed sheet. Next, 30 cycles of JASO-CCT testing (according to the conditions of M609-91, one cycle consisting of salt spray (35°C, 5% concentration, 2 hours), dry (60°C, 25% RH, 4 hours), and wet (50°C, 95% RH, 2 hours)) were performed, followed by a rust removal treatment. Next, the maximum pit depth was measured using a microscope by the focal depth method. In this evaluation, specimens with a maximum pit depth of less than 200 μm were marked with ○, and specimens with a maximum pit depth of 200 μm or more were marked with ×.

[0073] The results of the above evaluations are shown in Tables 5 and 6.

[0074]

[0075]

[0076] As shown in Table 5, the cold-rolled annealed sheets of Examples 1 to 24 were 10 3 The flow stress at 10% strain when a tensile test was conducted at a strain rate of 1 / sec and the Young's modulus at 900°C were both high, and the cold-rolled annealed sheets of Examples 1 to 24 also had good results in fracture elongation and corrosion resistance (maximum pitting depth) at room temperature, and were also excellent in workability and corrosion resistance. On the other hand, as shown in Table 6, the cold-rolled annealed sheets of Comparative Examples 1 to 4 had inappropriate annealing temperature or cooling rate conditions, and the amount of precipitates was too small, so 3 In a tensile test at a strain rate of 10 / s, either or both of the flow stress at 10% strain and the Young's modulus at 900°C were low. In addition, the cold-rolled annealed sheets of Comparative Examples 5 to 31 did not satisfy the predetermined composition, and in some of the comparative examples, the annealing temperature was also inappropriate. 3When a tensile test was conducted at a strain rate of 1 / s, either or both of the flow stress at 10% strain and the Young's modulus at 900°C were low. Furthermore, the cold-rolled annealed sheets of Comparative Examples 3 to 31 also had insufficient results for either or both of the fracture elongation and corrosion resistance (maximum pitting depth) at room temperature.

[0077] As can be seen from the above results, the present invention can provide a ferritic stainless steel material for battery components that has excellent battery protection performance and resistance to thermal runaway when the battery is subjected to an impact due to a collision accident or the like, a method for manufacturing the same, and a battery component.

[0078] Furthermore, based on the above results, the present invention can be embodied in the following aspects.

[0079] [1] A ferritic stainless steel material for battery components, which contains, by mass, C: 0.001 to 0.050%, Si: 0.01 to 2.00%, Mn: 0.01 to 2.00%, P: 0.010 to 0.050%, S: 0.0001 to 0.0100%, Cr: 10.0 to 30.0%, N: 0.001 to 0.050%, and further contains one or two selected from Ti: 0.01 to 0.50% and Nb: 0.01 to 0.60%, with the balance consisting of Fe and impurities, and contains 0.010 vol% or more of Ti-based precipitates and / or Nb-based precipitates.

[0080] [2] By mass, Ni: 0.01 to 2.00%, Al: 0.001 to 1.000%, Cu: 0.01 to 2.00%, Mo: 0.01 to 3.00%, V: 0.01 to 0.50%, Zr: 0.01 to 0.50%, B: 0.0002 to 0.0050%, Ca: 0.0005 to 0.0100%, W: 0.10 to 3.00%, Sn: 0.01 to 0.50%, Co: 0.03 to 0.30% , Mg: 0.0002 to 0.0100%, Sb: 0.005 to 0.300%, REM: 0.002 to 0.200%, Ga: 0.0002 to 0.3000%, Ta: 0.001 to 1.000%, Hf: 0.001 to 1.000%, Bi: 0.001 to 0.020%. The ferritic stainless steel material for battery components according to [1] further contains one or more selected from the group consisting of 0.0002 to 0.0100%, 0.005 to 0.300%, 0.002 to 0.200%, 0.0002 to 0.3000%, 0.001 to 1.000%, 0.001 to 1.000%, and 0.001 to 0.020%.

[0081] [3] The ferritic stainless steel material for battery components according to [1] or [2], wherein the particle size of the Ti-based precipitates and / or the Nb-based precipitates is 10 μm or less.

[0082] [4] 10 3 [1] to [3], wherein the ferritic stainless steel material for battery components has a flow stress of 500 MPa or more at 10% strain when subjected to a tensile test at a strain rate of 1 / sec, and a Young's modulus at 900°C of 80 GPa or more.

[0083] [5] The ferritic stainless steel material for battery components according to any one of [1] to [4], which satisfies one or more of the following properties: (1) a breaking elongation at room temperature of 30% or more; and (2) a maximum pitting depth of less than 200 μm.

[0084] [6] The ferritic stainless steel material for battery components according to any one of [1] to [5], having a thickness of 1.0 mm or less.

[0085] [7] A method for producing a ferritic stainless steel material for battery components, comprising, on a mass basis, C: 0.001 to 0.050%, Si: 0.01 to 2.00%, Mn: 0.01 to 2.00%, P: 0.010 to 0.050%, S: 0.0001 to 0.0100%, Cr: 10.0 to 30.0%, N: 0.001 to 0.050%, and further containing one or two selected from Ti: 0.01 to 0.50% and Nb: 0.01 to 0.60%, with the balance being Fe and impurities. Annealing the cold-rolled material at 850 to 1050 ° C., and then cooling to 800 ° C. at a cooling rate of 10 ° C. / second or less.

[0086] [8] The cold-rolled material contains, by mass, Ni: 0.01 to 2.00%, Al: 0.001 to 1.000%, Cu: 0.01 to 2.00%, Mo: 0.01 to 3.00%, V: 0.01 to 0.50%, Zr: 0.01 to 0.50%, B: 0.0002 to 0.0050%, Ca: 0.0005 to 0.0100%, W: 0.10 to 3.00%, Sn: 0.01 to 0.50%, Co: 0.03 to 0.30 %, Mg: 0.0002 to 0.0100%, Sb: 0.005 to 0.300%, REM: 0.002 to 0.200%, Ga: 0.0002 to 0.3000%, Ta: 0.001 to 1.000%, Hf: 0.001 to 1.000%, Bi: 0.001 to 0.020%. [7] The method for producing a ferritic stainless steel material for battery components according to the present invention, further containing one or more selected from the group consisting of 0.001 to 0.020%.

[0087] [9] The method for producing a ferritic stainless steel material for battery components according to [7] or [8], wherein the cooling is performed at a cooling rate of more than 10°C / second from 800°C to 400°C.

[0088]

[10] The method for producing a ferritic stainless steel material for battery components according to [9], wherein the cooling rate from 800°C to 400°C is 12°C / second or more.

[0089]

[11] A battery component comprising the ferritic stainless steel material for battery components according to any one of [1] to [6].

Claims

1. The composition contains, on a mass basis, C: 0.001-0.050%, Si: 0.01-2.00%, Mn: 0.01-2.00%, P: 0.010-0.050%, S: 0.0001-0.0100%, Cr: 10.0-30.0%, N: 0.001-0.050%, and further contains one or two selected from Ti: 0.01-0.50% and Nb: 0.01-0.60%, with the balance being Fe and impurities; A ferritic stainless steel material for battery components, containing 0.010 volume % or more of Ti-based precipitates and / or Nb-based precipitates.

2. By mass, Ni: 0.01 to 2.00%, Al: 0.001 to 1.000%, Cu: 0.01 to 2.00%, Mo: 0.01 to 3.00%, V: 0.01 to 0.50%, Zr: 0.01 to 0.50%, B: 0.0002 to 0.0050%, Ca: 0.0005 to 0.0100%, W: 0.10 to 3.00%, Sn: 0.01 to 0.50%, Co: 0.03 to 0.30% , Mg: 0.0002 to 0.0100%, Sb: 0.005 to 0.300%, REM: 0.002 to 0.200%, Ga: 0.0002 to 0.3000%, Ta: 0.001 to 1.000%, Hf: 0.001 to 1.000%, Bi: 0.001 to 0.020%. The ferritic stainless steel material for battery components according to claim 1, further containing one or more selected from the group consisting of 0.0002 to 0.0100%, 0.005 to 0.300%, 0.002 to 0.200%, 0.0002 to 0.3000%, 0.001 to 1.000%, 0.001 to 1.000%, and 0.001 to 0.020%.

3. 3. The ferritic stainless steel material for battery components according to claim 1, wherein the Ti-based precipitates and / or the Nb-based precipitates have a grain size of 10 μm or less.

4. 10 3 The flow stress at 10% strain when a tensile test is performed at a strain rate of 100 / s is 500 MPa or more, and 3. The ferritic stainless steel material for battery components according to claim 1 or 2, having a Young's modulus at 900° C. of 80 GPa or more.

5. The following characteristics: (1) The breaking elongation at room temperature is 30% or more. (2) The maximum pitting depth is less than 200 μm. The ferritic stainless steel material for battery components according to claim 1 or 2, which satisfies one or more of the following requirements.

6. The ferritic stainless steel material for battery components according to claim 1 or 2, having a thickness of 1.0 mm or less.

7. A method for producing a ferritic stainless steel material for battery components, comprising annealing a cold-rolled material having a composition, on a mass basis, of 0.001-0.050% C, 0.01-2.00% Si, 0.01-2.00% Mn, 0.010-0.050% P, 0.0001-0.0100%, 10.0-30.0% Cr, 0.001-0.050% N, and one or two selected from 0.01-0.50% Ti and 0.01-0.60% Nb, with the balance being Fe and impurities, at 850-1050°C, and then cooling to 800°C at a cooling rate of 10°C / sec or less.

8. The cold rolled material contains, by mass, 0.01 to 2.00% Ni, 0.001 to 1.000% Al, 0.01 to 2.00% Cu, 0.01 to 3.00% Mo, 0.01 to 0.50% V, 0.01 to 0.50% Zr, 0.0002 to 0.0050% B, 0.0005 to 0.0100% Ca, 0.10 to 3.00% W, 0.01 to 0.50% Sn, and 0.03 to 0.30% Co. %, Mg: 0.0002 to 0.0100%, Sb: 0.005 to 0.300%, REM: 0.002 to 0.200%, Ga: 0.0002 to 0.3000%, Ta: 0.001 to 1.000%, Hf: 0.001 to 1.000%, Bi: 0.001 to 0.020%. The method for producing a ferritic stainless steel material for battery components according to claim 7, further comprising one or more selected from the group consisting of 0.001 to 0.020%.

9. The method for producing a ferritic stainless steel material for battery components according to claim 7 or 8, wherein the cooling is performed at a cooling rate of more than 10°C / sec from 800°C to 400°C.

10. The method for producing a ferritic stainless steel material for battery components according to claim 9, wherein the cooling rate from 800°C to 400°C is 12°C / sec or more.

11. A battery component comprising the ferritic stainless steel material for battery components according to claim 1 or 2.