WO2011132793A1 - 非水電解質二次電池の負極材料およびその製造方法 - Google Patents
非水電解質二次電池の負極材料およびその製造方法 Download PDFInfo
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- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/134—Electrodes based on metals, Si or alloys
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- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/139—Processes of manufacture
- H01M4/1395—Processes of manufacture of electrodes based on metals, Si or alloys
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- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
- H01M4/387—Tin or alloys based on tin
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- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
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- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
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- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
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- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
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Definitions
- the present invention relates to a negative electrode material for a non-aqueous electrolyte secondary battery and a method for producing the same, and more particularly to a negative electrode material for a lithium ion secondary battery and a method for producing the same.
- Co—Sn compounds as negative electrode materials that can be expected to have a higher capacity than graphite materials in lithium ion secondary batteries.
- there are application examples such as CoSn and CoSn 2 as Co-Sn compounds.
- the cycle characteristics of the lithium ion secondary battery may deteriorate because the Co—Sn based compound repeatedly expands and contracts due to charging and discharging. It has been pointed out.
- Patent Document 1 discloses Co 3 Sn 2 as an example of an alloy that exhibits a high capacity as compared with a graphite material but does not cause excessive expansion and contraction and exhibits good cycle characteristics.
- Patent Document 2 discloses Co 3 Sn 2 as an example of an intermetallic compound that can be used as a negative electrode material.
- Patent Document 3 describes CoSn 2 as an intermetallic compound used for a negative electrode material, and discloses that Co 3 Sn 2 as a by-product thereof disappears by heat treatment.
- Patent Document 4 describes CoSn 2 as a target Co—Sn compound used as a negative electrode material, and Co 3 Sn 2, which is a by-product and a Co—Sn compound other than the target, is heat treated. Is disclosed.
- Patent Document 5 discloses a Co—Sn—Fe-based compound as a negative electrode material. As a measure for reducing expensive Co, it is possible to use cheap Fe as an element that is cheaper than Co and has an equivalent battery capacity. It is stated.
- JP 2001-250541 A Japanese Patent No. 4100195 JP 2006-100244 A JP 2008-179846 A JP 2009-48824 A
- Patent Documents 1-4 all describe the use of Co 3 Sn 2 as a negative electrode material.
- Patent Document 1 states that Co 3 Sn 2 has a higher capacity than a graphite material and has excellent cycle characteristics.
- Co 3 Sn 2 has a higher capacity than the graphite material, in the crystalline state, it has a lower capacity than the CoSn and CoSn 2 in the Co—Sn-based compound.
- As a negative electrode material it is desired to achieve both high capacity and excellent cycle characteristics.
- Patent Document 5 states that inexpensive Fe is used as an element that is cheaper than Co and has an equivalent battery capacity, and that the use of expensive Co is reduced, but the cycle characteristics when Fe is used are touched. There is room for consideration.
- An object of the present invention is to provide a negative electrode material for a non-aqueous electrolyte secondary battery that maintains the high capacity of a non-aqueous electrolyte secondary battery, typically a lithium ion secondary battery, and has excellent cycle characteristics, and a method for producing the same. Is to provide.
- Another object of the present invention is to provide a negative electrode material for a nonaqueous electrolyte secondary battery and a method for manufacturing the same, by suppressing the amount of expensive Co used.
- the non-aqueous electrolyte secondary battery provided with this negative electrode material has reduced cycle characteristics (hereinafter referred to as “the negative electrode material is excellent in cycle characteristics”), and the negative electrode material is a negative electrode according to the prior art. Compared to materials, it is inexpensive in that it can limit the amount of Co used.
- the degree of nanocrystallization of these alloy materials can be evaluated by the heat generation start temperature of the negative electrode material obtained by differential scanning calorimetry (DSC), and this heat generation start temperature is 375. What is necessary is just to perform nanocrystallization of said alloy so that it may become less than 4 degreeC.
- the “heat generation start temperature” without particular notice means the heat generation start temperature of the negative electrode material obtained by differential scanning calorimetry.
- mechanical treatment such as mechanical grinding treatment is suitable.
- mechanical grinding is referred to as MG
- mechanical grinding processing as MG processing
- time when the mechanical grinding processing is performed is referred to as MG time.
- a negative electrode material for a non-aqueous electrolyte secondary battery comprising at least the following three types of powdered materials, each of which is an alloy: The material A, the alloy material B, and the conductive material.
- the alloy material A includes an alloy having a CoSn 2 structure containing Co, Sn, and Fe, and the Sn content is 70.1% by mass or more with respect to the alloy material A.
- the alloy material B contains Co 3 Sn 2 and has a lower capacity than the alloy material A, and the alloy material B has a lower capacity than the alloy material A and the total mass of the alloy material B.
- R B is less than 27.1 percent greater than 5.9%, the content of the conductive material 7% by mass or more relative to the total of the alloy material a and alloy material B and the conductive material 20 mass%
- Negative electrode obtained by differential scanning calorimetry A negative electrode material for non-aqueous electrolyte secondary battery, wherein the heat generation starting temperature of charge is less than 375.4 ° C..
- the CoSn 2 structure alloy included in the alloy material A has a Co 1-x Fe x Sn y (where 0 ⁇ x ⁇ 0.5, 1.1 ⁇ y ⁇ 2.3).
- “capacity” means discharge capacity (unit: mA / g). Details of the method for measuring the discharge capacity will be described later.
- the conductive material may include graphite.
- the present invention also provides a method for producing a negative electrode material for a non-aqueous electrolyte secondary battery comprising the following steps: A first alloy material comprising forming an alloy material A including a CoSn 2 structure alloy containing Co, Sn, and Fe, wherein the Sn content is 70.1% by mass or more and less than 82.0% by mass Forming step; A second alloy material forming step comprising forming an alloy material B containing Co 3 Sn 2 having a lower capacity than the alloy material A; and the alloy material A, the alloy material B, and the conductive material, the mass of the alloy material A the mass ratio R B of the alloy material B to the total of the mass of alloy material B is less than 27.1 percent exceeded 5.9%, the content of the conductive material is an alloy material a and alloy material B conductive Mixing to obtain a negative electrode material having an exothermic onset temperature obtained by differential scanning calorimetry of less than 375.4 ° C. by mixing so as to be 7% by mass or more and 20% by mass or less
- MG mechanical grinding
- B mechanical grinding
- the mixing step includes a third MG process for mechanically grinding a mixture including at least the alloy material A and the alloy material B, and the third MG process includes the first MG process and the second MG process. It is more preferable to double as a treatment.
- the conductive material includes graphite
- the mixing step includes a fourth MG treatment that mechanically grinds the mixture including at least the alloy material A, the alloy material B, and the conductive material
- the fourth MG treatment includes the fourth MG treatment. It is preferable that the first MG process and the second MG process also serve.
- the negative electrode material of the nonaqueous electrolyte secondary battery according to the present invention includes the alloy material A and the alloy material B that are appropriately nanocrystallized, it has a high capacity and excellent cycle characteristics. Moreover, since the CoSn 2 structure alloy provided in the alloy material A has Fe instead of a part of Co, the amount of expensive Co used is suppressed as compared with the negative electrode material according to the prior art. Therefore, the negative electrode material according to the present invention is excellent in cost competitiveness.
- the “negative electrode material of a non-aqueous electrolyte secondary battery” is composed of a mixed material obtained by adding a conductive material to a metal material using a metal material as a raw material.
- the material is one that has undergone nanocrystallization.
- These negative electrode materials can be used as they are as non-aqueous electrolyte secondary batteries, specifically, as negative electrode active materials for lithium ion secondary batteries.
- the manufacturing method of a metal-type material is not limited.
- An example of the manufacturing method is a method of melting, casting, crushing / sizing, and mixing as necessary, and another example is a method of mechanically manufacturing an alloy from alloy raw materials (a specific example is mechanical alloying). Ing method).
- the negative electrode material of the nonaqueous electrolyte secondary battery according to the present invention includes at least three kinds of powdery materials, and these three kinds of powdery materials are alloy material A, alloy material B, and conductive material, respectively. is there.
- the shape of the powdery material is not particularly limited. In consideration of ease of use as the negative electrode material, it is preferable that the average particle diameter of any material is 0.1 ⁇ m or more and 100 ⁇ m or less.
- each powdery material will be described.
- the alloy material A and the alloy material B have undergone nanocrystallization, and mechanical treatment such as MG treatment may be performed in order to advance nanocrystallization. In such a case, the particle size of the alloy material is reduced, but a very fine powder is agglomerated, so the average particle size is typically in the range of about 1 ⁇ m to 20 ⁇ m.
- the alloy material A according to the present invention includes a CoSn 2 structure alloy containing Co, Sn and Fe (hereinafter also referred to as “alloy A”).
- alloy A Fe substitutes a part of Co in the CoSn 2 structure, and the ratio of Fe to Co in the alloy A (hereinafter also referred to as “Fe / Co ratio”) is preferably 1 or less.
- the composition of the alloy A is represented by Co 1-x Fe x Sn y (where 0 ⁇ x ⁇ 0.5, 1.1 ⁇ y ⁇ 2.3).
- the Sn content in the alloy material A according to the present invention is 70.1% by mass or more and less than 82.0% by mass with respect to the alloy material A. Preferably, they are 78.0 mass% or more and 80.1 mass% or less.
- the Sn content is excessively low, the discharge capacity of the alloy material A becomes too low, so that a high capacity negative electrode material cannot be obtained.
- the Sn content is excessively high, the cycle characteristics of the nonaqueous electrolyte secondary battery including the negative electrode material are deteriorated.
- Alloy material B contains Co 3 Sn 2 and has a lower capacity than the alloy material A. Then, the ratio R B of the mass of alloy material B to the total of the mass of the mass and alloy material B of the alloy material A is less than 27.1 percent exceed 5.9%. More preferably, R B is 23.5% less than 7.1%.
- the alloy material B Since the alloy material B has a lower capacity than the alloy material A, a material based on occlusion / release of charged particles (lithium ions when the non-aqueous electrolyte secondary battery is a lithium ion secondary battery) generated by charging / discharging. Is less than that of the alloy material A having a relatively high capacity. Since the alloy material A has a higher content in the negative electrode material than the alloy material B, the negative electrode material according to the present invention is an alloy material B having a relatively small volume variation and an alloy having a relatively large volume variation. A structure interspersed in the material A is provided. By providing such a structure, the stress change in the alloy material A caused by the volume fluctuation of the alloy material A is easily dispersed in the alloy material B.
- the stress change in the negative electrode material caused by charging / discharging is reduced, and as a result, the cycle characteristics of the nonaqueous electrolyte secondary battery including the negative electrode material are less likely to be deteriorated.
- the negative electrode material has excellent cycle characteristics.
- the crystals contained in the alloy material A and the alloy material B have been nanocrystallized.
- the ratio of the surface area to the volume of the crystal related to the alloy material A increases, so that the volume expansion when one crystal related to the alloy material A occludes charged particles such as lithium ions.
- the amount of the alloy material B that absorbs the stress change accompanying the increase is relatively increased, and the alloy material B easily absorbs the stress change.
- the capacity of the alloy material B increases as the degree of nanocrystallinity increases. That is, if only the alloy material B is seen, it will expand if it is nanocrystallized.
- the volume expansion coefficient accompanying charging of the alloy material B that has undergone nanocrystallization is relatively close to 1 in proportion to the volume expansion coefficient accompanying charging of the alloy material A. It is difficult to create a specific area.) Therefore, it is expected that the negative electrode material including the alloy material A and the alloy material B in which nanocrystallization has progressed is unlikely to cause cracking of the material when volumetric expansion is caused by charging.
- the negative electrode material of the nonaqueous electrolyte secondary battery according to the present invention includes a conductive material.
- the “conductive material” means a material having a high mobility of not only electrons but also charged particles that move in the negative electrode material with charge / discharge of lithium ions or the like.
- the typical conductivity of the conductive material according to the present invention is about 1 ⁇ 10 3 to 1 ⁇ 10 5 ⁇ cm in volume resistivity.
- the specific composition of the conductive material having such characteristics is not limited. Specific examples of such a conductive material include carbonaceous materials such as graphite and hard carbon, and intermetallic compounds such as CoSn.
- the higher the conductivity (mobility) of the conductive material the lower the internal resistance of the negative electrode material. Therefore, the higher the conductivity of the conductive material, the better. From this viewpoint, the conductive material is preferably made of graphite.
- the content of the conductive material in the negative electrode material according to the present invention is 7% by mass or more and 20% by mass or less with respect to the total of the alloy material A, the alloy material B, and the conductive material. If the content of the conductive material is excessively high, the capacity of the whole negative electrode material is reduced, and if the content of the conductive material is excessively low, it is difficult to obtain a negative electrode material having excellent cycle characteristics.
- the negative electrode material according to the present invention may contain materials other than the above-mentioned alloy material A, alloy material B, and conductive material, but should be of a type and content that do not impair the characteristics of the negative electrode material. It is. Examples of other acceptable materials include carbonaceous materials such as graphite and hard carbon.
- the negative electrode material of the nonaqueous electrolyte secondary battery according to the present invention has a characteristic that the heat generation start temperature obtained by differential scanning calorimetry is less than 375.4 ° C. More preferably, the heat generation start temperature is 227.8 ° C. or higher and 331.4 ° C. or lower.
- the region with an incomplete crystal state increases, so that strain accumulated in the crystal is released or recrystallization occurs at a lower temperature. Since these crystal state changes are exothermic reactions, the lower the exothermic onset temperature, the lower the crystal integrity of the alloy contained in the negative electrode material to be measured, that is, the negative electrode material to be measured. It shows that the alloy material A and the alloy material B contained in the material have undergone nanocrystallization. Therefore, the heat generation start temperature is an index indicating the degree of nanocrystallization of alloy material A and alloy material B.
- the heat generation start temperature is less than 375.4 ° C.
- the negative electrode material according to the present invention achieves both a high capacity and a reduction in cycle characteristics of a nonaqueous electrolyte secondary battery including the negative electrode material.
- the heat generation start temperature is preferably 331.4 ° C. or lower.
- the heat generation start temperature is preferably 227.8 ° C. or higher.
- the negative electrode material according to the present invention is not particularly limited as long as the negative electrode material has the above-described compositional characteristics and heat generation start temperature characteristics.
- a preferred example of the method for producing a negative electrode material according to the present invention is a method comprising the following steps: A first alloy material comprising forming an alloy material A including a CoSn 2 structure alloy containing Co, Sn, and Fe, wherein the Sn content is 70.1% by mass or more and less than 82.0% by mass Forming step; A second alloy material forming step comprising forming an alloy material B containing Co 3 Sn 2 having a lower capacity than the alloy material A; and the alloy material A, the alloy material B, and the conductive material, the mass of the alloy material A the mass ratio R B of the alloy material B to the total of the mass of alloy material B is less than 27.1 percent exceeded 5.9%, the content of the conductive material is an alloy material a and alloy material B conductive A mixing step comprising obtaining a negative electrode material having a heat generation start temperature in differential scanning calorimetry of less than 375.4 ° C. by mixing so as to be 7% by mass or more and 20% by mass or less with respect to the total of the material.
- the above method preferably includes a first MG treatment for mechanically grinding the alloy material A and a second MG treatment for mechanically grinding the alloy material B.
- the mixing step includes a third MG process for mechanically grinding a mixture including at least the alloy material A and the alloy material B, and the third MG process includes the first MG process and the second MG process. It is more preferable to serve as both.
- the conductive material includes graphite
- the mixing step includes a fourth MG treatment that mechanically grinds the mixture including at least the alloy material A, the alloy material B, and the conductive material
- the fourth MG treatment includes the fourth MG treatment. It is preferable that the first MG process and the second MG process also serve.
- Alloy material Alloy material A is produced by melting, casting, crushing, and sizing the metal as a raw material.
- the casting is preferably performed by rapid solidification. Since alloy material A contains Fe in addition to Co and Sn, the amount of expensive Co used can be suppressed without significantly reducing the capacity of the battery.
- the alloy material B is produced by melting, casting, crushing and sizing the metal as a raw material. Again, casting is preferably performed by rapid solidification.
- the alloy material B contains Co 3 Sn 2 . It is preferable that the content of Co 3 Sn 2 in the alloy material B is high, and it is more preferable that the alloy material B is substantially composed only of Co 3 Sn 2 .
- Alloy material A and alloy material B contain impurities that are inevitably mixed in from the raw materials or in the manufacturing process.
- the manufacturing method of the alloy material A a manufacturing method including melting, casting by rapid solidification, pulverization / size control will be described.
- the manufacturing method of the alloy material B is the same as that of the alloy material A.
- Melting is performed by heating the granular alloy raw material placed in a melting crucible in a non-oxidizing atmosphere to completely dissolve it.
- a melting crucible a crucible having an inner surface formed of a material that has heat resistance at the melting temperature of the alloy raw material and does not react with the alloy raw material can be used.
- a melting crucible made of alumina it is preferable to use.
- High-frequency induction heating can be used as a heating method for melting.
- an appropriate heating method such as Ar arc heating or electron beam heating can be used.
- the non-oxidizing atmosphere is preferably a nitrogen, helium, or argon atmosphere or in a vacuum. In order to manufacture the alloy material A, an argon atmosphere is more preferable.
- Strip casting may be used for rapid solidification.
- the strip casting method is a method in which the melt is poured onto a water-cooled roll rotating from a slit provided on the lower surface of the tundish, and the melt is rapidly and rapidly solidified.
- a melt spinning method a twin roll quenching method, a gas atomizing method, a water atomizing method, a rotating electrode method, and the like can be used.
- Grinding can be performed using a ball mill, a universal mill equipped with pins, or the like.
- a roll quenching method such as a strip casting method, a melt spinning method, or a twin roll quenching method
- a flaky alloy is produced, and thus further pulverization is performed.
- classification may be performed by classifying using a sieve having an appropriate opening.
- the gas atomizing method, the water atomizing method, or the mechanical alloying method is used, a powdered alloy is generated at the stage of rapid solidification, and therefore it is not necessary to pulverize thereafter.
- the means for preparing the conductive material is arbitrary. As a specific example, it can be obtained by pulverizing a raw material of a conductive material such as massive graphite using a known grinding means such as a ball mill.
- Negative electrode material Mixing means for alloy material A, alloy material B, and conductive material thus obtained is arbitrary.
- a known means such as a ball mill or a blender may be used.
- the mixture obtained by carrying out the mixing means satisfies the conditions of the heat generation start temperature, the mixture becomes the negative electrode material according to the present invention as it is.
- the powder obtained in the process of reaching the above mixture, or some kind of treatment is applied to the mixture, and the heat generation start temperature is Promote nanocrystallization of alloy material A and / or alloy material B contained in the mixture until less than 375.4 ° C.
- the specific means of such processing is not limited, but machine processing such as MG processing is a typical example. In the following description, MG processing will be described as a specific example.
- MG processing conditions are not limited. Any conditions may be used as long as the heat generation start temperature of the negative electrode material can be less than 375.4 ° C. When the MG treatment conditions are excessively loose, the promotion of nanocrystallization is insufficient and it becomes difficult to set the heat generation start temperature to less than 375.4 ° C. When the MG treatment conditions are excessively severe, the alloy material The MG treatment conditions may be appropriately set in consideration of the fact that the material is substantially amorphous and the capacity of the negative electrode material is reduced.
- the object to be subjected to the MG treatment is both the alloy material A and the alloy material B. That is, the negative electrode material manufacturing method according to the present invention is based on the MG treatment (first MG treatment) of the alloy material A and the alloy material B. It is preferable to provide the MG process (second MG process). By performing MG treatment on both materials, the capacity of both materials is increased to increase the capacity as the negative electrode material, and the stress change in the negative electrode material caused by charging and discharging is further reduced. From the viewpoint of simplification of the process, a third MG treatment for mechanically grinding the mixture having the alloy material A and the alloy material B is provided, and the third MG treatment is the first MG treatment and the second MG treatment. It is preferable to also serve as MG treatment.
- the MG treatment is performed on the mixture of the alloy material A, the alloy material B, and the conductive material.
- the reason is unknown, but when an MG treatment is performed on a mixture containing a conductive material containing graphite, a negative electrode material having particularly excellent characteristics can be obtained. That is, a fourth MG process is performed in which a mixture having at least the alloy material A, the alloy material B, and the conductive material is mechanically ground, and the fourth MG process is performed by the first MG process and the second MG process. It is particularly preferable to serve as both.
- the alloy material A according to the present invention is mainly composed of CoSn 2 in which part of Co is replaced by Fe (that is, alloy A), and the alloy material B is mainly composed of Co 3 Sn 2 . Therefore, a negative electrode material made of CoSn 2 and a negative electrode material made of Co 3 Sn 2 were prepared, and the charge / discharge characteristics of these negative electrode materials were first examined. Below, the manufacturing method of these negative electrode materials and the evaluation method of charging / discharging characteristics are described.
- the intermetallic compound powder made of CoSn 2 before MG treatment obtained above was subjected to MG treatment using a planetary ball mill (Super Misni) manufactured by Nisshin Giken Co., Ltd. in a nitrogen atmosphere, and CoSn 2
- the negative electrode material which consists of was obtained.
- the mass ratio of CoSn 2 and the ball was set to 10: 100, and the ball diameter was 6.25 mm.
- 0, 4, 24, 48, and 96 hours were examined for MG time.
- the intermetallic compound powder composed of Co 3 Sn 2 before MG treatment was similarly treated with MG to obtain a negative electrode material composed of Co 3 Sn 2 .
- acetylene black (AB) as a conductive material, styrene butadiene rubber (SBR) as a binder, and carboxymethyl cellulose (CMC) as a thickener were added to the obtained CoSn 2 .
- These were kneaded to obtain an electrode plate component.
- the electrode plate component was applied onto a copper foil serving as a current collector and dried to obtain an electrode.
- the mass of the dried electrode plate constituting material on the electrode was measured to calculate the mass of the CoSn 2 from the mass ratio of CoSn 2 of the electrode plate structure material in, and the mass of the negative electrode material contained in the battery.
- the mass of the negative electrode material can be the mass of the negative electrode active material.
- LiPF 6 lithium hexafluorophosphate
- EC ethylene carbonate
- DMC dimethyl carbonate
- EMC ethyl methyl carbonate
- VC vinylene carbonate
- FEC fluoroethylene carbonate
- EC ethylene carbonate
- DMC dimethyl carbonate
- EMC ethyl methyl carbonate
- VC vinylene carbonate
- FEC fluoroethylene carbonate
- the battery obtained above was subjected to a charge / discharge test to evaluate the discharge capacity, initial efficiency, and cycle maintenance rate.
- charging is performed when Li is occluded in the electrode as the working electrode, and discharging is performed when Li is released from the electrode.
- constant current charging is performed up to a predetermined interelectrode voltage, and after reaching the predetermined interelectrode voltage, constant voltage charging is performed until a predetermined current density is reached.
- As the discharge constant current discharge was performed up to a predetermined interelectrode voltage.
- charging / discharging was repeated in order to evaluate discharge capacity and cycle maintenance factor.
- the charge / discharge test was conducted at an environmental temperature of 20 ° C.
- constant current charging is performed at a current density of 1 mA / cm 2 until the voltage between the electrodes reaches 5 mV.
- constant voltage charging is performed until the current density reaches 0.01 mA / cm 2.
- Went constant current discharge was performed at a current density of 1 mA / cm 2 until the voltage between the electrodes reached 1.5V.
- a value obtained by integrating the current (mA / g) per 1 g of the mass of the negative electrode active material contained in the battery by the discharge time (h) was defined as the discharge capacity (mAh / g).
- a value obtained by integrating the current (mA / g) per 1 g of the mass of the negative electrode active material contained in the battery by the charging time (h) was defined as a charging capacity (mAh / g).
- the value of (discharge capacity at the first cycle) / (charge capacity at the first cycle) ⁇ 100 was defined as the initial efficiency (%).
- the above charge / discharge test was repeated 50 cycles, and the value of (discharge capacity at the 50th cycle) / (discharge capacity at the first cycle) ⁇ 100 was defined as the cycle retention rate (%).
- Table 1 shows the evaluation results of the charge / discharge characteristics of CoSn 2 and Co 3 Sn 2 .
- the discharge capacity, the initial efficiency, and the cycle maintenance rate at each MG time can be compared for CoSn 2 and Co 3 Sn 2 .
- the discharge capacity was 665.4 mAh / g
- the initial efficiency was 86.0%
- the largest values were obtained for the discharge capacity and the initial efficiency.
- the cycle retention rate was 90.4%, and the largest value for the cycle retention rate was obtained.
- FIG. 1 is a diagram illustrating the relationship between MG time and discharge capacity for CoSn 2 and Co 3 Sn 2 .
- the vertical axis represents discharge capacity (unit: mAh / g)
- the horizontal axis represents MG time (unit: time).
- CoSn 2 has a larger discharge capacity when the MG time is 0 hour compared with Co 3 Sn 2 .
- the discharge capacity reached its maximum value, and then gradually decreased as the MG time increased.
- Co 3 Sn 2 had a small discharge capacity when the MG time was 0 hours, but when the MG time was 24 hours, the discharge capacity became more than twice that when the MG time was 0 hours and became the maximum value.
- the maximum value of the discharge capacity was 665.4 mAh / g for CoSn 2 and 399.1 mAh / g for Co 3 Sn 2 . Since the theoretical capacity of graphite is 372 mAh / g, it was confirmed that both CoSn 2 and Co 3 Sn 2 have higher capacity than graphite. It was also found that the relationship between the MG time and the discharge capacity varies depending on the composition of Co—Sn compounds. Next, in order to investigate this relationship, X-ray diffraction measurement was performed.
- FIG. 2 is a diagram showing measurement results of X-ray diffraction at each MG time for Co 3 Sn 2 .
- the horizontal axis of FIG. 2 represents 2 ⁇ (unit: °) ( ⁇ is the Bragg reflection angle), and the vertical axis represents the intensity of diffraction lines (unit: counts).
- RINT1000 X-ray diffraction apparatus manufactured by Rigaku Corporation was used.
- Cu was used for the target.
- FIG. 3 is a schematic diagram for explaining how Li diffuses in the crystal.
- the state of Li diffusion is indicated by black arrows.
- FIG. 3A is a diagram for explaining the case of graphite, for example. In the case of graphite, Li is smoothly diffused between layers in the crystal.
- FIG. 3B is a diagram for explaining a case where the Co 3 Sn 2 MG process is not performed. When MG treatment is not performed, the crystal grains are large and the reaction area is also small. When this is used for the negative electrode material of the battery, since Li diffusion of Co 3 Sn 2 is slow, Li does not move to the inside of the crystal at the time of charging, so a large overvoltage is applied and charging is completed.
- FIG. 3A is a diagram for explaining the case of graphite, for example. In the case of graphite, Li is smoothly diffused between layers in the crystal.
- FIG. 3B is a diagram for explaining a case where the Co 3 Sn 2 MG process is not performed. When MG treatment is
- 3C is a diagram for explaining the case where the Co 3 Sn 2 MG process is performed.
- the crystal grains are small and the reaction area is large. Since nano-crystallized materials have a large number of Li diffusion paths, it is considered that Li is smoothly diffused and the capacity increases.
- Co 3 Sn 2 differs from CoSn 2 in that the discharge capacity increases as the MG time increases.
- the cycle characteristics are also good, and if Co 3 Sn 2 subjected to MG treatment is applied to the negative electrode material, it is predicted that a material having very excellent cycle characteristics can be obtained.
- CoSn 2 has a higher capacity than Co 3 Sn 2 .
- CoSn 2 since CoSn 2 repeatedly expands and contracts due to charging and discharging, the cycle characteristics deteriorate.
- Co 3 Sn 2 has a lower capacity than CoSn 2 but has good cycle characteristics.
- Co 3 Sn 2 which is a low-capacity phase coexists with CoSn 2 which is a high-capacity phase, so that stress caused by the volume change of the high-capacity phase due to charge and discharge is alleviated, and the fine powder of the negative-electrode material Control. And the cycling characteristics of negative electrode material become favorable. That is, if an appropriate amount of CoSn 2 having a high capacity and Co 3 Sn 2 having good cycle characteristics are combined and applied to the negative electrode material, a negative electrode material having high capacity and excellent cycle characteristics can be obtained.
- a negative electrode material in which a part of Co in CoSn 2 was substituted with Fe was produced as follows.
- As a replacement product of Fe 25% the mass ratio of Co: Fe: Sn was blended so as to be 14.9: 5.0: 80.1.
- As a replacement product of Fe 50% Co: Fe: Sn was blended so that the mass ratio was 9.9: 10.0: 80.1.
- the Fe 75% substitution product was blended so that the mass ratio of Co: Fe: Sn was 4.9: 15.0: 80.1.
- FeSn 2 as a substitute for Fe 100% was blended so that the mass ratio of Fe: Sn was 20.2: 79.8. Except for the blending amount of the alloy raw material, it was manufactured in the same manner as in CoSn 2 . However, MG processing was not performed here. The charge / discharge characteristics of the obtained material were evaluated in the same manner as described above.
- Table 2 is a table for explaining the results of evaluating the Fe substitution amount and charge / discharge characteristics in CoSn 2 .
- the discharge capacity increased.
- the initial efficiency showed no noticeable tendency. It was confirmed that the cycle retention rate was significantly reduced as the amount of Fe substitution increased. From this, it has been found that the cycle characteristics are remarkably lowered when the Fe substitution amount is increased. In order to investigate this factor, X-ray diffraction measurement was performed next.
- FIG. 4 is a diagram for explaining the results of measuring X-ray diffraction for a material subjected to Fe substitution in CoSn 2 .
- the horizontal and horizontal axes in FIG. 4 are the same as those in FIG.
- X-ray diffraction measurement was performed in the same manner as when X-ray diffraction was measured at each MG time for Co 3 Sn 2 (FIG. 2).
- the measurements were made material, CoSn 2, FE50% replacements, are FeSn 2 as Fe75% replacements, and FE100% replacements.
- a material obtained by performing MG treatment on the material subjected to Fe substitution in CoSn 2 was prepared, and X-ray diffraction measurement was performed.
- X-ray diffraction measurement was performed in the same manner as in the case where X-ray diffraction was measured at each MG time for Co 3 Sn 2 .
- the MG treatment was performed in the same manner as described above, and the MG time was 48 hours when the cycle characteristics of CoSn 2 were the best.
- FIG. 5 is a diagram for explaining the result of MG treatment of a material subjected to Fe substitution in CoSn 2 and measuring X-ray diffraction.
- the amount of Fe substitution when replacing a part of Co with Fe in CoSn 2 is preferably 50% by mass or less. Therefore, in the following experiment, the alloy material A was obtained by replacing 50% by mass or less of Co in CoSn 2 with Fe. Co 3 Sn 2 was used as the alloy material B. Graphite was further mixed as a conductive material into the mixture of alloy material A and alloy material B. That is, an experiment was conducted using a mixture of alloy material A, alloy material B, and graphite as a negative electrode material.
- a negative electrode material (hereinafter referred to as “reference negative electrode material”) serving as a reference for the optimization study was prepared for the optimization study.
- the compounding ratio of Sn in the alloy material A was 79.8% by mass
- the ratio RB of the alloy material B to the total of the mass of the alloy material A and the mass of the alloy material B was 20.0% by mass. .
- the amount of graphite added is the ratio of the mass of graphite to the sum of the mass of alloy material A, the mass of alloy material B, and the mass of graphite (in other words, alloy material A, alloy material B, and graphite as a conductive material). content) R C of the graphite to the total of the 15.0 wt%.
- the MG time was 24 hours.
- the reference negative electrode material thus obtained is Example 1 in Table 3 to be described later.
- the reference negative electrode material was obtained by performing MG treatment in combination of alloy material A, alloy material B, and graphite. Alloy material A and alloy material B were produced separately by the two alloy method.
- the method of dividing the alloy raw material into two and melting and casting each alloy raw material separately is called a two-alloy method.
- the method of melting and casting all the alloy raw materials at once is usually called a casting method.
- Co 3 Sn 2 was produced in the same manner as in the production of the alloy material A, except that the Co: Sn mass ratio was 42.7: 57.3 so that the alloy material B was Co 3 Sn 2. Got.
- alloy material A (Mixing of raw materials)
- alloy material B (Mixing of raw materials)
- graphite 68.0: 17.0: 15.0, thereby obtaining a mixture. It was.
- R B is 20.0 wt%
- R C was 15.0 wt%.
- the average particle size was about 45 ⁇ m for alloy material A, 38 ⁇ m for alloy material B, and about 25 ⁇ m for graphite.
- MG processing The above mixture was subjected to MG treatment in a nitrogen atmosphere using a planetary ball mill (Super Misni) manufactured by Nisshin Giken Co., Ltd. At this time, the mass ratio of the mixture to the ball was set to 10: 100, and the ball diameter was 6.25 mm. The MG time was 24 hours. Here, what was obtained by performing the MG treatment was used as a reference negative electrode material.
- FIG. 6 is a diagram for explaining the result of observing the reference negative electrode material obtained above with a transmission electron microscope (TEM). Measurement was performed using a transmission electron microscope (JEM-3010) manufactured by JEOL Ltd. As a pretreatment of the measurement sample, platinum coating was applied to the reference negative electrode material, and then the surface was processed by sputtering with a focused ion beam apparatus (FIB). Here, surface processing was performed using a focused ion beam processing observation apparatus (FB-2000A) manufactured by Hitachi, Ltd. As shown in FIG.
- TEM transmission electron microscope
- the reference negative electrode material has a configuration in which nanocrystals having a crystal size of 1 ⁇ m or less appearing as a black portion are scattered in a material (hereinafter also referred to as “base material”) that forms a matrix. It was confirmed that it was prepared.
- FIG. 7 shows an enlarged view of where the nanocrystals are seen. As a result of observing the nanocrystals indicated by arrows in FIG. 7, the electron diffraction image of Co 3 Sn 2 shown in FIG. was gotten.
- FIG. 9 shows a state in which the base material is enlarged and observed, and qualitative analysis was performed using two points with different contrasts in the base material as A part and B part as measurement locations.
- 10A and 10B are diagrams for explaining the analysis results.
- FIG. 10A shows the analysis result of the A part shown in FIG. 9, and
- FIG. 10B shows the analysis result of the B part shown in FIG. Co, Fe, Sn, and C peaks were obtained from both the A part and the B part.
- Co and Sn peaks are prominently observed, and it is considered that a substance based on alloy material A or alloy material B is the main component.
- the C peak is more prominent than the Co and Sn peaks, and it is considered that the substance based on graphite is the main component. From these results, it was confirmed that alloy material A, alloy material B, and graphite were mixed in the negative electrode material.
- Table 3 is a table explaining the raw material composition and various evaluation results of each example and each comparative example.
- Table 3 is a table explaining the raw material composition and various evaluation results of each example and each comparative example.
- (a) shows the result of studying the composition of alloy material A (denoted as alloy A in the table).
- the result of examining the mixing ratio of the alloy material A and the alloy material B (denoted as alloy B in the table) is shown in (b).
- the result of examining the amount of graphite is shown in (c).
- the result of examining the MG time and the heat generation start temperature is shown in (d).
- the discharge capacity, initial efficiency, and cycle maintenance rate were evaluated as charge / discharge characteristics of each negative electrode material.
- the charge / discharge characteristics were evaluated in the same manner as described above.
- the optimized pass line was determined to have a discharge capacity of 520.0 mAh / g or more and a cycle maintenance ratio of 95.0% or more.
- Table 3 (a) shows comparative examples and examples in which the composition of the alloy material A is changed. Except having changed the mass ratio at the time of mix
- Comparative Example a-1 was blended so that the mass ratio of Co: Fe: Sn was 9.0: 9.0: 82.0.
- Example a-2 was blended so that the mass ratio of Co: Fe: Sn was 9.1: 9.1: 81.8.
- Example a-3 was blended so that the mass ratio of Co: Fe: Sn was 9.9: 10.0: 80.1.
- the mass ratio of Co: Fe: Sn was 10.1: 10.1: 79.8.
- Example a-4 was blended so that the mass ratio of Co: Fe: Sn was 15.0: 14.9: 70.1.
- Comparative Example a-5 was formulated so that the mass ratio of Co: Fe: Sn was 16.9: 17.0: 66.1
- Comparative Example a-1 having the highest Sn blending ratio had an extremely low exothermic start temperature, which was below the pass line for optimization of the cycle retention rate.
- Example a-2, Example 1, Example a-3, and Example a-4 exceeded the optimization pass line.
- Comparative Example a-5 since the Sn blending ratio was small, the heat generation start temperature was too high, and the discharge capacity was lower than the pass line.
- the ratio of the mass of Sn to the mass of the alloy material A (that is, the content of Sn with respect to the alloy material A, hereinafter also referred to as “R S ”) is 70.1% by mass or more and 82.0%. Less than mass% is preferable. More preferably, RS is 70.1 mass% or more and 80.1 mass% or less.
- Table 3 (b) shows comparative examples and examples in which the mixing ratio of the alloy material A and the alloy material B is changed. Except that the mixing ratio of alloy material A and alloy material B was changed, the anode material was prepared, the battery was produced, and the charge / discharge characteristics were evaluated in the same manner as in Example 1.
- R B ratio of the mass of the alloy material B to the sum of the mass of the alloy material A and the mass of the alloy material B
- Example b-2 is R B is 7.1 mass%.
- Example 1 is 20.0% by weight R B.
- Example b-3 is 23.5% by weight R B.
- Example b-4 is 25.9 weight percent R B.
- Comparative Example b-5 is a 27.1% by weight R B.
- Table 3 (c) shows comparative examples and examples in which the amount of graphite was changed. Except that the amount of graphite was changed, the negative electrode material was prepared, the battery was produced, and the charge / discharge characteristics were evaluated in the same manner as in Example 1.
- R C ratio of the mass of the graphite to the sum of the mass of the alloy material A, the mass of the alloy material B, and the mass of the graphite
- RC is 15.0 mass%.
- Example c-2 R C is 10.0 mass%.
- Example c-3 R C is 7.0 mass%.
- Comparative Example c-4 R C is 5.0% by mass.
- Comparative Example c-4 which had the smallest carbon blending ratio, was below the pass line for optimization of the cycle retention rate.
- Example c-1, Example 1, Example c-2, and Example c-3 exceeded the optimization pass line.
- RC is preferably 7.0% by mass or more and 20.0% by mass or less. More preferably, RC is 10.0 mass% or more and 20.0 mass% or less.
- (D) of Table 3 shows a comparative example and an example in which the MG time is changed. Except having changed MG time, it carried out similarly to Example 1, and performed preparation of negative electrode material, preparation of a battery, and evaluation of charging / discharging characteristics.
- the MG time is 5 hours.
- the MG time is 10 hours.
- the MG time is 24 hours.
- Comparative Example d-1 which had the shortest MG time, had a high heat generation start temperature and was below the pass line for optimization of the cycle maintenance rate.
- the other examples d-2 and Example 1 exceeded the optimization pass line. From this, it is preferable that the MG time exceeds 5 hours. More preferably, the MG time is 10 hours or more and 24 hours or less.
- FIG. 11 is a diagram for explaining the results of differential scanning calorimetry for Comparative Example d-1, Example d-2, and Example 1 in which the MG time is changed.
- FIG. 11 (a) shows the measurement result of Comparative Example d-1
- FIG. 11 (b) shows the measurement result of Example d-2
- FIG. 11 (c) shows the measurement result of Example 1.
- 11A, 11B, and 11C the vertical axis represents heat flow (unit: mW), and the horizontal axis represents temperature (unit: ° C.).
- DSC6200R differential scanning calorimeter
- the range of temperature rise was 20 ° C. to 750 ° C.
- the heating rate was 10 ° C./min.
- the exothermic peak at the time of temperature rise shows an exothermic reaction.
- the lowest exothermic peak is peak-separated, the tangent of the separated peak on the exothermic start side (shown by a broken line in the figure) and the flat part before the exotherm occurs
- a heat generation start temperature is obtained as an intersection with an extension line (also indicated by a broken line).
- the heat generation starting temperatures were 375.4 ° C. for Comparative Example d-1, 331.4 ° C. for Example d-2, and 227.8 ° C. for Example 1. It was found that the heat generation start temperature decreases as the MG time increases.
- the heat generation start temperature in the differential scanning calorimetry was set to less than 375.4 ° C. More preferably, the heat generation start temperature is 227.8 ° C. or higher and 331.4 ° C. or lower.
- the negative electrode material for a non-aqueous electrolyte secondary battery and a method for producing the same according to the present invention can be used for a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery.
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Abstract
Description
(1)Co、SnおよびFeを含有しCoSn2構造の合金(FeはCoの一部を置換している。)を含んでなる合金材料A、Co3Sn2を含有し合金材料Aよりも放電容量が低い合金材料B、および導電材(典型的にはグラファイトなどの導電性炭素質材料が例示される。)を所定の含有量の範囲で含む混合体について、合金材料Aおよび合金材料Bのナノ結晶化度を高めることにより、その混合体を備える非水電解質二次電池の負極材料の容量を高めることができる。また、この負極材料を備える非水電解質二次電池はサイクル特性の低下が抑制され(以下、この特性を「負極材料はサイクル特性に優れる」という。)、かつこの負極材料は従来技術に係る負極材料に比べてCoの使用量を制限できる点で安価である。
上記の導電材はグラファイトを含んでいてもよい。
Co、SnおよびFeを含有するCoSn2構造の合金を含み、うちSnの含有量は70.1質量%以上82.0質量%未満である合金材料Aを形成することを備える第一の合金材料形成工程;
合金材料Aよりも低容量のCo3Sn2を含む合金材料Bを形成することを備える第二の合金材料形成工程;ならびに
合金材料Aと合金材料Bと導電材とを、合金材料Aの質量と合金材料Bの質量との合計に対する合金材料Bの質量の割合RBが5.9%を超え27.1%未満であって、導電材の含有量が合金材料Aと合金材料Bと導電材との合計に対して7質量%以上20質量%以下となるように混合して、示差走査熱量測定により得られた発熱開始温度が375.4℃未満である負極材料を得ることを備える混合工程。
1.負極材料の組成
本発明において、「非水電解質二次電池の負極材料」とは、金属系物質を原料とする金属系材料に導電材を加えて得られる混合材料からなり、少なくとも金属系材料はナノ結晶化が進行したものである。これらの負極材料はそのまま非水電解質二次電池、具体例を挙げればリチウムイオン二次電池の負極活物質として使用することができる。金属系材料の製造方法は限定されない。その製造方法の一例は溶解、鋳造、粉砕・整粒、および必要に応じ混合を行う方法であり、別の一例は、合金原料から機械的に合金を製造する方法(具体的な一例はメカニカルアロイング法)である。
本発明に係る合金材料Aは、Co、SnおよびFeを含有するCoSn2構造の合金(以下、「合金A」ともいう。)を含む。この合金Aにおいて、FeはCoSn2構造におけるCoの一部を置換しており、合金AにおけるFeのCoに対する比率(以下、「Fe/Co比」ともいう。)は1以下であることが好ましい。換言すれば、合金Aの組成はCo1-xFexSny(ここで、0<x<0.5、1.1≦y<2.3)で表される。合金AにおけるFe/Co比が過度に大きくなると、後述するように、その合金Aを含む負極材料を備える非水電解質二次電池のサイクル特性が低下する。
本発明に係る合金材料Bは、Co3Sn2を含有し、合金材料Aよりも低容量である。そして、合金材料Aの質量と合金材料Bの質量との合計に対する合金材料Bの質量の割合RBは、5.9%を超え27.1%未満である。より好ましくは、RBは7.1%以上23.5%以下である。
本発明に係る非水電解質二次電池の負極材料は導電材を含む。本発明において「導電材」とは、電子のみならず、リチウムイオンなどの充放電に伴い負極材料内を移動する荷電粒子の移動度が高い材料を意味する。本発明に係る導電材の典型的な導電性は、体積抵抗率として1×103から1×105Ωcm程度である。かかる特性を備える導電材の具体的な組成は限定されない。そのような導電材の具体例として、グラファイトおよびハードカーボン等の炭素質材料、CoSn等の金属間化合物等が挙げられる。導電材の導電率(移動度)が高いほど負極材料の内部抵抗が低くなるため、導電材の導電率は高ければ高いほど好ましい。かかる観点から導電材はグラファイトからなることが好ましい。
本発明に係る負極材料は上記の合金材料A、合金材料Bおよび導電材以外の材料を含有してもよいが、負極材料としての特性を損ねない種類、および含有量とすべきである。許容される他の材料として、グラファイト、ハードカーボンなどの炭素質材料が例示される。
本発明に係る非水電解質二次電池の負極材料は、その示差走査熱量測定により得られた発熱開始温度が375.4℃未満である特性を有する。より好ましくは、発熱開始温度は227.8℃以上331.4℃以下である。
本発明に係る負極材料は上記の組成上の特徴および発熱開始温度の特性を備えていれば、その製造方法は特に限定されない。
Co、SnおよびFeを含有するCoSn2構造の合金を含み、うちSnの含有量は70.1質量%以上82.0質量%未満である合金材料Aを形成することを備える第一の合金材料形成工程;
合金材料Aよりも低容量のCo3Sn2を含む合金材料Bを形成することを備える第二の合金材料形成工程;ならびに
合金材料Aと合金材料Bと導電材とを、合金材料Aの質量と合金材料Bの質量との合計に対する合金材料Bの質量の割合RBが5.9%を超え27.1%未満であって、導電材の含有量が合金材料Aと合金材料Bと導電材との合計に対して7質量%以上20質量%以下となるように混合して、示差走査熱量測定における発熱開始温度が375.4℃未満である負極材料を得ることを備える混合工程。
合金材料Aは、原料となる金属の溶解、鋳造、粉砕・整粒を行って生成される。ここで鋳造は、急冷凝固によって行われることが好ましい。合金材料AはCoおよびSnに加えてFeを含有するため、電池の容量をあまり減少させることなく高価なCoの使用量を抑制できる。
以下に、合金材料Aの製造方法の一例として、溶解、急冷凝固による鋳造、粉砕・整粒からなる製造方法について説明する。合金材料Bの製造方法についても合金材料Aの場合と同様である。
溶解るつぼは、合金原料の溶解温度において耐熱性があり、かつ合金原料と反応しない材質で内面が形成されたるつぼを用いることができる。例えば、合金材料Aを製造するためにはアルミナ製の溶解るつぼを用いることが好ましい。
(2)導電材
導電材の調製手段は任意である。具体的な一例を挙げれば、塊状のグラファイトなど導電材の原料物質をボールミルなど公知の粉砕手段を用いて粉末化することによって得ることができる。
こうして得られた合金材料A、合金材料B、および導電材の混合手段は任意である。ボールミル、ブレンダ一等を公知の手段を用いればよい。混合手段の実施により得られた混合体が発熱開始温度の条件を満たしている場合には、その混合体がそのまま本発明に係る負極材料となる。
本発明に係る合金材料AはCoSn2においてCoの一部をFeに置換したもの(すなわち合金A)を主成分とし、合金材料BはCo3Sn2を主成分とする。そこで、CoSn2からなる負極材料とCo3Sn2からなる負極材料とそれぞれ用意し、これらの負極材料の充放電特性をまず調べた。以下では、これらの負極材料の製造と充放電特性の評価方法について述べる。
Co:Snの質量比をCo:Sn=19.9:80.1に配合した合金原料を、アルミナ製溶解るつぼに入れ、アルゴン雰囲気にて1400℃まで高周波誘導加熱して完全に溶解させた。その後、周速70m/minで回転する銅製の水冷ロールを用いたストリップキャスティング法により急冷凝固させて、薄片状の鋳片とした。このときの液相線温度と固相線温度との間における冷却速度は約5000℃/secであった。この鋳片を、ピンミルを用いて粉砕し、MG処理前のCoSn2からなる金属間化合物粉体を得た。この際、粉砕後の鋳片のほぼ全量が106μmの目の篩を通るように粉砕時間を設定した。
Co:Snの質量比を42.7:57.3に配合した合金原料を、CoSn2の製造と同様の処理を行い、MG処理前のCo3Sn2からなる金属間化合物粉体を得た。
上記で得られたMG処理前のCoSn2からなる金属間化合物粉体を、窒素雰囲気中、日新技研(株)製遊星ボールミル(スーパーミスニ)を用いて、MG処理を実施し、CoSn2からなる負極材料を得た。この際、CoSn2とボールとの質量比は10:100となるようにし、ボール径は6.25mmのものを用いた。また、MG時間は、0、4、24、48、および96時間を検討した。MG処理前のCo3Sn2からなる金属間化合物粉体についても同様にMG処理を行い、Co3Sn2からなる負極材料を得た。
上記で得られたCoSn2からなる負極材料およびCo3Sn2からなる負極材料を用いた電池の充放電特性を評価するために評価用電池を作製し、充放電特性を評価した。電池の作製と充放電特性の評価に関して、以後特に断りのない限り、CoSn2からなる負極材料を単にCoSn2、Co3Sn2からなる負極材料を単にCo3Sn2と呼ぶ。評価の手順としてCoSn2の場合を説明するが、Co3Sn2の場合もCoSn2の場合と同様にした。
図1は、CoSn2とCo3Sn2とについてMG時間と放電容量との関係性を説明する図である。図1において、縦軸は放電容量(単位:mAh/g)であり、横軸はMG時間(単位:時間)である。CoSn2は、MG時間が0時間での放電容量がCo3Sn2と比較すると大きい。また、MG時間が4時間のとき放電容量が最大値をとり、その後MG時間の増加に伴って緩やかに下降した。Co3Sn2は、MG時間が0時間での放電容量は小さいが、MG時間が24時間のとき、放電容量は、MG時間が0時間のときの2倍以上になり最大値となった。なお、放電容量の最大値は、CoSn2が665.4mAh/g、Co3Sn2が399.1mAh/gであった。グラファイトの理論容量が372mAh/gであるから、CoSn2、Co3Sn2ともにグラファイトより高容量であることが確認された。また、Co-Sn系化合物においても、その組成によって、MG時間と放電容量との関係性に相違がみられることが分かった。この関係性について調査するため、次にX線回折測定を行った。
CoSn2のCoの一部をFeに置換した負極材料は以下のようにして製造した。Co:Snの質量比がCo:Sn=19.9:80.1となるように配合した合金原料のCoの一部をFeに置き換えた合金材料を4種用意した。Fe25%置換品としては、Co:Fe:Snの質量比が14.9:5.0:80.1となるように配合した。Fe50%置換品としては、Co:Fe:Snの質量比が9.9:10.0:80.1となるように配合した。Fe75%置換品としては、Co:Fe:Snの質量比が4.9:15.0:80.1となるように配合した。Fe100%置換品としてのFeSn2は、Fe:Snの質量比が20.2:79.8となるように配合した。合金原料の配合量以外は、CoSn2のときと同様に製造した。ただし、ここではMG処理は行わなかった。得られた材料に対して、充放電特性を上記と同様に評価した。
Co:Fe:Snの質量比が10.1:10.1:79.8となるように配合した合金原料を、アルミナ製溶解るつぼに入れ、アルゴン雰囲気にて1400℃まで高周波誘導加熱して完全に溶解させた。その後、周速70m/minで回転する銅製の水冷ロールを用いたストリップキャスティング法により急冷凝固させて、薄片状の鋳片とした。このときの液相線温度と固相線温度との間の冷却速度は約5000℃/secであった。この鋳片をピンミルを用いて粉砕し、CoSn2におけるCoの50質量%をFeに置換した合金材料Aを得た。
合金材料BがCo3Sn2となるように、Co:Snの質量比が42.7:57.3となるように配合したこと以外は、合金材料Aの製造と同様にしてCo3Sn2を得た。
得られた合金材料A、合金材料B、およびグラファイトを質量比で、合金材料A:合金材料B:グラファイト=68.0:17.0:15.0となるように混合し、混合体を得た。このとき、RBは、20.0質量%であり、RCは15.0質量%であった。なお、平均粒径は、合金材料Aが45μm,合金材料Bが38μm,グラファイトが25μm程度であった。
日新技研(株)製の遊星ボールミル(スーパーミスニ)を用いて、窒素雰囲気中、上記の混合体にMG処理を施した。この際、混合体とボールとの質量比は10:100となるようにし、ボール径は6.25mmのものを用いた。また、MG時間は24時間とした。ここで、MG処理を行って得られたものを基準負極材料とした。
Claims (6)
- 非水電解質二次電池の負極材料であって、
当該負極材料は、少なくとも3種類の粉末状材料を備え、
該3種類の粉末状材料はそれぞれ、合金材料A、合金材料Bおよび導電材であり、
前記合金材料Aは、Co、SnおよびFeを含有するCoSn2構造の合金を含み、そのSn含有量は合金材料Aに対して70.1質量%以上82.0質量%未満であり、
前記合金材料BはCo3Sn2を含有し、かつ合金材料Aよりも低容量であり、
前記合金材料Aの質量と前記合金材料Bの質量との合計に対する前記合金材料Bの質量の割合RBは、5.9%を超え27.1%未満であり、
前記導電材の含有量は前記合金材料Aと前記合金材料Bと前記導電材との合計に対して7質量%以上20質量%以下であり、
示差走査熱量測定により得られた前記負極材料の発熱開始温度が375.4℃未満である
ことを特徴とする非水電解質二次電池の負極材料。 - 請求項1に記載の非水電解質二次電池の負極材料であって、前記導電材はグラファイトを含む、非水電解質二次電池の負極材料。
- Co、SnおよびFeを含有するCoSn2構造の合金を含み、うちSnの含有量は70.1質量%以上82.0質量%未満である合金材料Aを形成することを備える第一の合金材料形成工程;
前記合金材料Aよりも低容量のCo3Sn2を含む合金材料Bを形成することを備える第二の合金材料形成工程;ならびに
前記合金材料Aと前記合金材料Bと導電材とを、前記合金材料Aの質量と前記合金材料Bの質量の合計に対する前記合金材料Bの質量の割合RBが5.9%を超え27.1%未満であって、前記導電材の含有量が全成分の混合体に対して7質量%以上20質量%以下となるように混合して、示差走査熱量測定により得られた発熱開始温度が375.4℃未満である負極材料を得ることを備える混合工程
を有することを特徴とする非水電解質二次電池の負極材料の製造方法。 - 前記合金材料Aをメカニカルグラインディング処理する第一のMG処理および前記合金材料Bをメカニカルグラインディング処理する第二のMG処理を備える請求項3記載の製造方法。
- 前記混合工程は少なくとも前記合金材料Aと前記合金材料Bとを有する混合体をメカニカルグラインディング処理する第三のMG処理を備え、該第三のMG処理が前記第一のMG処理および第二のMG処理を兼ねる請求項4記載の製造方法。
- 前記導電材はグラファイトを含み、
前記混合工程は、少なくとも前記合金材料A、前記合金材料Bおよび前記導電材を有する混合体をメカニカルグラインディング処理する第四のMG処理を備え、該第四の処理が前記第一のMG処理および第二のMG処理を兼ねる請求項4記載の製造方法。
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Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2001250541A (ja) | 2000-03-06 | 2001-09-14 | Matsushita Electric Ind Co Ltd | 非水電解質二次電池 |
JP2002251992A (ja) * | 2001-02-22 | 2002-09-06 | Kureha Chem Ind Co Ltd | 非水溶媒二次電池用電極材料、電極および二次電池 |
JP2004006206A (ja) * | 2001-09-28 | 2004-01-08 | Toshiba Corp | 非水電解質電池用負極材料、負極、非水電解質電池及び非水電解質電池用負極材料の製造方法 |
JP2004183019A (ja) * | 2002-11-29 | 2004-07-02 | Toshiba Corp | 非水電解質電池用電極材料及び非水電解質電池 |
JP2006100244A (ja) | 2004-09-06 | 2006-04-13 | Pionics Co Ltd | リチウム二次電池用負極活物質粒子と負極及びそれらの製造方法 |
JP2006236835A (ja) * | 2005-02-25 | 2006-09-07 | Sumitomo Metal Ind Ltd | 非水系二次電池用負極材料とその製造方法 |
JP2007335418A (ja) * | 2007-08-27 | 2007-12-27 | Sumitomo Metal Ind Ltd | 非水電解質二次電池用負極材料 |
JP2008066025A (ja) * | 2006-09-05 | 2008-03-21 | Sumitomo Metal Ind Ltd | 非水電解質二次電池用負極材料およびその製造方法 |
JP4100175B2 (ja) | 2003-01-09 | 2008-06-11 | 松下電器産業株式会社 | リチウムイオン二次電池用負極 |
JP2008179846A (ja) | 2007-01-23 | 2008-08-07 | Seiko Epson Corp | 金属粉末の製造方法、金属粉末、電極およびリチウムイオン二次電池 |
JP2009048824A (ja) | 2007-08-17 | 2009-03-05 | Sanyo Special Steel Co Ltd | リチウムイオン電池負極材用粉末 |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CA2310374C (en) | 1998-09-18 | 2007-09-04 | Canon Kabushiki Kaisha | Electrode material for anode of rechargeable lithium battery, electrode structural body using said electrode material, rechargeable lithium battery using said electrode structuralbody, process for producing said electrode structural body, and process for producing said rechargeable lithium battery |
JP3620703B2 (ja) | 1998-09-18 | 2005-02-16 | キヤノン株式会社 | 二次電池用負極電極材、電極構造体、二次電池、及びこれらの製造方法 |
CN101577332B (zh) | 2008-05-06 | 2014-03-12 | 安泰科技股份有限公司 | 一种锂离子电池负极材料及其制备方法 |
CN101339990B (zh) * | 2008-08-27 | 2011-11-30 | 安泰科技股份有限公司 | 一种锂离子二次电池负极活性材料及其制备方法 |
CN102782906B (zh) * | 2009-12-25 | 2015-02-25 | 新日铁住金株式会社 | 非水电解质二次电池的负极材料及其制造方法 |
-
2011
- 2011-04-25 KR KR1020127030475A patent/KR101505257B1/ko not_active IP Right Cessation
- 2011-04-25 EP EP11772124.1A patent/EP2562853A4/en not_active Withdrawn
- 2011-04-25 US US13/642,284 patent/US9028711B2/en not_active Expired - Fee Related
- 2011-04-25 CN CN2011800309382A patent/CN103003984A/zh active Pending
- 2011-04-25 WO PCT/JP2011/060039 patent/WO2011132793A1/ja active Application Filing
- 2011-04-25 JP JP2012511732A patent/JP5218700B2/ja not_active Expired - Fee Related
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2001250541A (ja) | 2000-03-06 | 2001-09-14 | Matsushita Electric Ind Co Ltd | 非水電解質二次電池 |
JP2002251992A (ja) * | 2001-02-22 | 2002-09-06 | Kureha Chem Ind Co Ltd | 非水溶媒二次電池用電極材料、電極および二次電池 |
JP2004006206A (ja) * | 2001-09-28 | 2004-01-08 | Toshiba Corp | 非水電解質電池用負極材料、負極、非水電解質電池及び非水電解質電池用負極材料の製造方法 |
JP2004183019A (ja) * | 2002-11-29 | 2004-07-02 | Toshiba Corp | 非水電解質電池用電極材料及び非水電解質電池 |
JP4100175B2 (ja) | 2003-01-09 | 2008-06-11 | 松下電器産業株式会社 | リチウムイオン二次電池用負極 |
JP2006100244A (ja) | 2004-09-06 | 2006-04-13 | Pionics Co Ltd | リチウム二次電池用負極活物質粒子と負極及びそれらの製造方法 |
JP2006236835A (ja) * | 2005-02-25 | 2006-09-07 | Sumitomo Metal Ind Ltd | 非水系二次電池用負極材料とその製造方法 |
JP2008066025A (ja) * | 2006-09-05 | 2008-03-21 | Sumitomo Metal Ind Ltd | 非水電解質二次電池用負極材料およびその製造方法 |
JP2008179846A (ja) | 2007-01-23 | 2008-08-07 | Seiko Epson Corp | 金属粉末の製造方法、金属粉末、電極およびリチウムイオン二次電池 |
JP2009048824A (ja) | 2007-08-17 | 2009-03-05 | Sanyo Special Steel Co Ltd | リチウムイオン電池負極材用粉末 |
JP2007335418A (ja) * | 2007-08-27 | 2007-12-27 | Sumitomo Metal Ind Ltd | 非水電解質二次電池用負極材料 |
Non-Patent Citations (1)
Title |
---|
See also references of EP2562853A4 * |
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