WO2011125722A1 - リチウム二次電池用正極材料及びその製造方法、並びにリチウム二次電池用正極及びリチウム二次電池 - Google Patents
リチウム二次電池用正極材料及びその製造方法、並びにリチウム二次電池用正極及びリチウム二次電池 Download PDFInfo
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- C01G45/1228—Manganates or manganites with a manganese oxidation state of Mn(III), Mn(IV) or mixtures thereof of the type [MnO2]n-, e.g. LiMnO2, Li[MxMn1-x]O2
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- C01G45/1242—Manganates or manganites with a manganese oxidation state of Mn(III), Mn(IV) or mixtures thereof of the type [Mn2O4]-, e.g. LiMn2O4, Li[MxMn2-x]O4
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Definitions
- the present invention relates to a positive electrode active material used for a lithium secondary battery, a manufacturing method thereof, a positive electrode for a lithium secondary battery using the positive electrode active material, and a lithium secondary battery including the positive electrode for the lithium secondary battery.
- a positive electrode active material used for a lithium secondary battery a manufacturing method thereof, a positive electrode for a lithium secondary battery using the positive electrode active material, and a lithium secondary battery including the positive electrode for the lithium secondary battery.
- Lithium secondary batteries are excellent in energy density and output density, and are effective in reducing the size and weight. Therefore, the demand for power supplies for portable devices such as notebook computers, mobile phones, and handy video cameras is growing rapidly. ing. Lithium secondary batteries are also attracting attention as power sources for electric vehicles and power load leveling, and in recent years, demand for power sources for hybrid electric vehicles is rapidly expanding. In particular, in electric vehicle applications, it is necessary to be excellent in low cost, safety, life (particularly under high temperature) and load characteristics, and improvements in materials are desired. *
- the positive electrode active material a substance having a function capable of desorbing and inserting lithium ions can be used.
- these positive electrode active material materials each having its own characteristics.
- a common problem for improving performance is to improve load characteristics, and improvements in materials are strongly desired.
- a material having a good performance balance that is excellent in low cost, safety, and life (particularly under high temperatures).
- a lithium manganese composite oxide having a spinel structure As a positive electrode active material for a lithium secondary battery, a lithium manganese composite oxide having a spinel structure, a layered lithium nickel composite oxide, a layered lithium cobalt composite oxide, and the like have been put into practical use. All of the lithium secondary batteries using these lithium-containing composite oxides have advantages and disadvantages in terms of characteristics. That is, a lithium manganese composite oxide having a spinel structure is inexpensive and relatively easy to synthesize, and is excellent in safety when used as a battery, but has a low capacity and inferior high-temperature characteristics (cycle and storage). Layered lithium-nickel composite oxides have high capacity and excellent high-temperature characteristics, but are difficult to synthesize, have inferior safety when used as batteries, and have drawbacks such as requiring careful storage. Layered lithium cobalt-based composite oxides are widely used as power sources for portable devices because they are easy to synthesize and have an excellent balance of battery performance. However, they are not sufficient in safety and costly. It is
- lithium nickel manganese cobalt-based composite oxides having a layered structure have been overcome as disadvantages of these positive electrode active material materials as possible candidates for active material materials that can overcome or be reduced as much as possible and are excellent in battery performance balance. Proposed. Particularly, in recent years, demands for lowering costs, higher voltages, and increasing safety demands are promising as positive electrode active material materials that can meet any of the demands. *
- Patent Document 1 discloses that Li x M y O 2 synthesized after reacting a cobalt sulfate aqueous solution and a sodium bicarbonate aqueous solution, filtering the precipitate, washing with water, and drying to obtain basic cobalt, It is disclosed that by using Li x M y O 2 containing a specific amount of (SO 4 ) as a positive electrode active material, corrosion of an aluminum foil used as a current collector is prevented and battery performance is improved. Yes.
- Patent Document 2 the LiNi a Co b M c O 2 , a mixture of AlX (SO 4) 2 ⁇ 12H 2 O, by heat treatment, by covering the AlX (SO 4) 2 as a positive electrode active material It is disclosed that self-discharge characteristics and storage characteristics can be improved.
- Patent Document 3 a lithium transition metal composite oxide having a spinel Mn structure is dispersed in water, a metal component and sulfur are added to the dispersion under pH control, and a coating layer is formed by a precipitation reaction, followed by filtration. It is disclosed that the safety, discharge capacity, and cycle characteristics can be improved by coating sulfur on the lithium transition metal composite oxide by drying.
- Patent Document 4 a transition metal raw material of a LiNiMnCoO 2 type lithium transition metal composite oxide and an S-containing compound are mixed, and the Li raw material is added and then fired, whereby the lithium transition metal composite oxide powder is obtained. Lowering the pH is disclosed.
- Patent Document 5 a compound having a P atom or an S atom is mixed with a LiCoO 2 -based lithium transition metal composite oxide and heat treated at 900 ° C., thereby suppressing gas generation and increase in internal resistance under high temperature storage. It is disclosed that it is possible.
- Patent Document 1 since the lithium source and the transition metal source and the compound containing an S atom in the structural formula are not crushed, it is difficult for the S atom to uniformly enter the secondary particles, It is difficult to achieve cost reduction and battery performance improvement which are the objects of the present invention.
- Patent Document 2 and Patent Document 3 an S-containing compound is mixed with a lithium transition metal composite oxide and heat-treated at a low temperature of 500 ° C. or lower. For this reason, S atoms cannot enter the secondary particles.
- the S-containing compound is mixed after the lithium transition metal composite oxide is synthesized, the powder characteristics cannot be improved, and it is difficult to achieve the object of the present invention.
- Patent Document 4 after mixing a transition metal raw material and S containing compound, and spray-drying, further mixing Li raw material and heat-processing at high temperature, pH of lithium transition metal complex oxide powder is adjusted. Lowering is disclosed. However, since the Li raw material is mixed after spray drying and heat-treated at a high temperature, the specific surface area is low. Moreover, there is no description regarding the high specific surface area by addition of S containing compound. Furthermore, Patent Document 4 does not describe a measure for suppressing such a decrease in specific surface area due to high-temperature firing.
- the inventors have made the inside of the secondary particles porous while making the active material sufficiently crystalline at the stage of firing the active material. We thought that it was important to obtain certain particles and studied them eagerly.
- the main component raw materials are simultaneously pulverized in a liquid medium, and a slurry in which these are uniformly dispersed is spray-dried and fired.
- a lithium secondary battery positive electrode material we have achieved low cost, high voltage resistance, high safety, and improved load characteristics such as rate and output characteristics. was possible.
- physical property changes such as a decrease in specific surface area occur, and thus a new problem of a decrease in discharge capacity at a high current density has been encountered.
- the present invention does not decrease the bulk density and increases the specific surface area of the active material, so that when used as a lithium secondary battery positive electrode material, the cost is reduced and the capacity is increased, and the safety is high, and the performance
- An object of the present invention is to provide a positive electrode active material for a lithium secondary battery capable of realizing an excellent lithium secondary battery.
- additive element 1 At least one element selected from Group 16 elements in the structural table in the third and subsequent periods of the periodic table.
- this invention relates to the following positive electrode material for lithium secondary batteries, its manufacturing method, the positive electrode for lithium secondary batteries, and a lithium secondary battery.
- a powder comprising a lithium transition metal compound having a function capable of inserting / extracting lithium ions, wherein at least selected from Group 16 elements in the third and subsequent periods of the periodic table inside the powder particles
- Lithium for lithium secondary battery positive electrode material having one element and a compound having a peak by SEM-EDX method derived from at least one element selected from Group 5 to 7 elements in the 5th and 6th periods Transition metal compound powder.
- the lithium transition metal-based compound is a powder composed of secondary particles composed of primary particles having two or more kinds of compositions, and at least inside the secondary particles, a Group 16 element after the third period of the periodic table And a primary particle of a compound having a peak by a SEM-EDX method derived from at least one element selected from the group 5 to 7 elements in the 5th and 6th periods
- the lithium transition metal-based compound powder for a lithium secondary battery positive electrode material according to (1) is a powder composed of secondary particles composed of primary particles having two or more kinds of compositions, and at least inside the secondary particles, a Group 16 element after the third period of the periodic table And a primary particle of a compound having a peak by a SEM-EDX method derived from at least one element selected from the group 5 to 7 elements in the 5th and 6th periods.
- (6) The above (5), wherein at least one element selected from Group 5 to 7 elements of the 5th period and 6th period is at least one element selected from the group consisting of Mo, W, Nb, Ta and Re ( 1) The lithium transition metal compound powder for a lithium secondary battery positive electrode material described in any one of (5).
- the molar ratio of the sum of S, Se, Te and Po elements to the sum of metal elements other than Li, S, Se, Te, Po, Mo, W, Nb, Ta and Re elements on the surface of the secondary particles is 2
- the lithium transition metal compound powder for a lithium secondary battery positive electrode material according to any one of the above (2) to (7) which is 500 times or less of the molar ratio of the entire secondary particles.
- the molar ratio of the total of Mo, W, Nb, Ta and Re elements to the total of metal elements other than Li, S, Se, Te, Po, Mo, W, Nb, Ta and Re elements on the surface part of secondary particles is The lithium transition metal-based compound powder for a lithium secondary battery positive electrode material according to any one of (2) to (8), which is 1.05 times or more of the molar ratio of the entire secondary particles. (10) The lithium transition metal-based compound powder for a lithium secondary battery positive electrode material according to any one of (1) to (9), wherein the BET specific surface area is 0.5 m 2 / g or more and 3 m 2 / g or less.
- the lithium transition metal compound is a lithium nickel manganese cobalt composite oxide having a layered structure or a lithium manganese composite oxide having a spinel structure.
- Lithium transition metal compound powder for secondary battery positive electrode material is represented by the following composition formula (A) or (B).
- Li 1 + x MO 2 (A) (In the above formula (A), x is 0 or more and 0.5 or less, M is an element composed of Li, Ni and Mn, or Li, Ni, Mn and Co, and Mn / Ni mole) (The ratio is 0.1 or more and 5 or less, the Co / (Mn + Ni + Co) molar ratio is 0 or more and 0.35 or less, and the Li molar ratio in M is 0.001 or more and 0.2 or less.) Li [Li a M ′ b Mn 2-ba ] O 4 + ⁇ (B) (In the above formula (B), a, b, and ⁇ satisfy 0 ⁇ a ⁇ 0.3, 0.4 ⁇ b ⁇ 0.6, ⁇ 0.5 ⁇ ⁇ ⁇ 0.5, and M ′ Represents at least one of transition metals selected from Ni, Cr, Fe, Co and Cu.) (14) The lithium transition metal-based compound powder for a lithium secondary battery positive electrode material according to any one of
- a lithium compound In a liquid medium, a lithium compound, at least one transition metal compound selected from Mn, Co, and Ni, and a compound containing at least one element selected from Group 16 elements in the third and subsequent periods of the periodic table
- a lithium secondary battery positive electrode material comprising a step of preparing a slurry in which the slurry is uniformly dispersed, a spray drying step of spray drying the slurry, and a firing step of firing the obtained spray dried body Method for producing lithium transition metal compound powder.
- a lithium compound, the transition metal compound, and a compound containing at least one element selected from Group 16 elements after the third period of the periodic table are measured in a liquid medium according to the following conditions: Crush until the median diameter is 0.6 ⁇ m or less,
- the slurry viscosity during spray drying is V (cP)
- the slurry supply amount is S (L / min)
- the gas supply amount is G (L / min)
- 50 cP ⁇ V ⁇ 7000 cP 500 ⁇
- the median diameter measurement conditions are as follows. i) After performing ultrasonic dispersion with an output of 30 W and a frequency of 22.5 kHz for 5 minutes, ii) Using a laser diffraction / scattering particle size distribution measuring device, set the refractive index to 1.24, and measure the median diameter using the particle diameter reference as the volume reference. (18) (16) or (17), wherein the transition metal compound includes at least a nickel compound, a manganese compound, and a cobalt compound, and in the firing step, the spray-dried body is fired at 1000 ° C. or higher in an oxygen-containing gas atmosphere. Of lithium transition metal compound powder for lithium secondary battery positive electrode material.
- a lithium secondary comprising a positive electrode active material layer and a current collector containing a lithium transition metal compound powder for a lithium secondary battery positive electrode material according to any one of (1) to (15) and a binder. Battery positive electrode.
- a lithium secondary battery comprising a negative electrode capable of inserting and extracting lithium, a non-aqueous electrolyte containing a lithium salt, and a positive electrode capable of inserting and extracting lithium, wherein the positive electrode is the lithium secondary described in (20) above A lithium secondary battery which is a positive electrode for a battery.
- the positive electrode active material for a lithium secondary battery of the present invention does not decrease the bulk density and increases the specific surface area of the active material, so that when used as a lithium secondary battery positive electrode material, the cost is reduced and the capacity is increased. Can be achieved. For this reason, according to the present invention, a lithium secondary battery that is inexpensive and excellent in performance is provided.
- FIG. 1 is an SEM image (photograph) of the lithium nickel manganese cobalt composite oxide powder produced in Example 1.
- FIG. FIG. 2 is an SEM image (photograph) of the lithium nickel manganese cobalt composite oxide powder produced in Example 2.
- FIG. 3 is an SEM image (photograph) of the lithium nickel manganese cobalt composite oxide powder produced in Comparative Example 1.
- 4 is an SEM image (photograph) of the lithium nickel manganese cobalt composite oxide powder produced in Comparative Example 2.
- FIG. 5 is an SEM image (photograph) of the lithium nickel manganese cobalt composite oxide powder produced in Example 3.
- 6 is an SEM image (photograph) of the lithium nickel manganese cobalt composite oxide powder produced in Comparative Example 3.
- FIG. 7A is an SEM-EDX image (photograph) of the lithium nickel manganese cobalt composite oxide powder produced in Example 3, and FIG. 7B is an SEM-EDX spectrum of the powder.
- FIG. 8 is a pore distribution curve of the lithium nickel manganese cobalt composite oxide powder produced in Example 3.
- FIG. 9 is a schematic diagram relating to “inside the particle” as used in the present invention.
- the positive electrode active material of the present invention is as follows. (1) A powder containing a lithium transition metal compound having a function capable of inserting / extracting lithium ions, from inside the particles of the powder, from a group 16 element after the third period of the periodic table At least one element selected (hereinafter also referred to as “additive element 1 of the present invention”), and at least one element selected from Group 5 to 7 elements in the fifth and sixth periods of the periodic table (hereinafter “ Also referred to as “additive element 2” of the present invention.) A lithium transition metal compound powder for a lithium secondary battery positive electrode material containing a compound having a peak obtained by SEM-EDX method.
- a lithium transition metal compound having a function capable of inserting / extracting lithium ions, and the raw material of the lithium transition metal compound is at least one selected from Group 16 elements in the third and subsequent periods of the periodic table And a compound having at least one element selected from Group 5 to 7 elements in the fifth and sixth periods (additive element 2 of the present invention) Lithium transition metal compound powder for lithium secondary battery positive electrode material obtained by firing.
- the lithium transition metal compound is a compound having a structure capable of desorbing and inserting Li ions, and examples thereof include sulfides, phosphate compounds, and lithium transition metal composite oxides.
- sulfides include compounds having a two-dimensional layered structure such as TiS 2 and MoS 2 , and strong compounds represented by the general formula Me x Mo 6 S 8 (Me is various transition metals including Pb, Ag, and Cu). Examples thereof include a sugar compound having a three-dimensional skeleton structure.
- Examples of the phosphate compound include those belonging to the olivine structure, and are generally represented by LiMePO 4 (Me is at least one transition metal), specifically, LiFePO 4 , LiCoPO 4 , LiNiPO 4 , LiMnPO 4 . 4 etc. are mentioned.
- Examples of the lithium transition metal composite oxide include spinel structures capable of three-dimensional diffusion and those belonging to a layered structure capable of two-dimensional diffusion of lithium ions. Those having a spinel structure are generally expressed as LiMe 2 O 4 (Me is at least one transition metal), specifically, LiMn 2 O 4 , LiCoMnO 4 , LiNi 0.5 Mn 1.5 O 4. , LiCoVO 4 and the like.
- LiMeO 2 (Me is at least one transition metal), specifically, LiCoO 2 , LiNiO 2 , LiNi 1-x Co x O 2 , LiNi 1-x—. y Co x Mn y O 2 , LiNi 0.5 Mn 0.5 O 2 , Li 1.2 Cr 0.4 Mn 0.4 O 2 , Li 1.2 Cr 0.4 Ti 0.4 O 2 , LiMnO 2 etc. are mentioned.
- the lithium transition metal compound powder of the present invention preferably has an olivine structure, a spinel structure, or a layered structure from the viewpoint of lithium ion diffusion.
- those having a layered structure or a spinel structure are preferred, and those having a layered structure are particularly preferred from the viewpoint that the expansion and contraction of the crystal lattice accompanying charge / discharge is large and the effects of the present invention are remarkable.
- foreign elements may be introduced into the lithium transition metal compound powder of the present invention.
- Different elements include B, Na, Mg, Al, K, Ca, Ti, V, Cr, Fe, Cu, Zn, Sr, Y, Zr, Nb, Ru, Rh, Pd, Ag, In, Sn, Sb. Te, Ba, Ta, Mo, W, Re, Os, Ir, Pt, Au, Pb, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu , Bi, N, F, Cl, Br, or I.
- These foreign elements may be incorporated into the crystal structure of the lithium nickel manganese cobalt composite oxide, or may not be incorporated into the crystal structure of the lithium nickel manganese cobalt composite oxide. It may be unevenly distributed as a single substance or a compound in the boundary. *
- additive element 1 of the present invention it is preferable that most of the “additive element 1 of the present invention” or “additive element 2 of the present invention” is present on the surface of the secondary particles, but a part thereof is replaced with a transition metal layer. May be.
- additive element 1 of the present invention or “additive element 2 of the present invention” is substituted in the transition metal layer, the basic skeleton of the lithium transition metal is described in the form of the general formula (1) described later. Moreover, the compound by which the one part was substituted is also included.
- the lithium transition metal-based compound powder for lithium secondary battery positive electrode material of the present invention (hereinafter also referred to as “lithium transition metal-based compound powder of the present invention”) has a function capable of inserting and extracting lithium ions.
- the lithium transition metal compound is a powder composed of secondary particles composed of primary particles having two or more kinds of compositions, and at least inside the secondary particles, a Group 16 element after the third period Derived from at least one element selected from (additive element 1 of the present invention) and at least one element selected from group 5-7 elements of the fifth and sixth periods (additive element 2 of the present invention) It is preferable to have primary particles of a compound having a peak by SEM-EDX method.
- the inside of the secondary particles in the structure of the secondary particles formed by aggregation of the primary particles, from the outer edge of the secondary particles, with respect to the average particle diameter of the secondary particles, The inside of the 5% diameter is called the inside.
- the presence or absence of crystallinity can be observed by observing XRD or TEM using the same particles. That is, in the case of XRD, for example, the crystalline “additive element 1 of the present invention corresponding to Li 2 SO 4 , LiHSO 4 , Li 2 SeO 4 , Li 2 TeO 4 , Li 2 TeO 3 , Li 2 Te2O 5, etc. If the peak of the compound having “and the additive element 2 of the present invention” can be observed, it can be analyzed that it is crystalline.
- additive element 1 of the present invention or “additive element 2 of the present invention” is so low that it cannot be analyzed by XRD, it is crystalline if a spot derived from a crystalline compound can be observed by TEM observation. It can be said.
- the lithium transition metal-based compound powder of the present invention has at least one element selected from elements derived from the additive 1 of the present invention, that is, Group 16 elements after the third period of the periodic table, on the surface portion of the primary particles. More preferably, (additive element 1 of the present invention) is present in a concentrated state.
- the molar ratio of the total amount of the additive elements to the total of the metal elements other than Li and the additive elements (that is, the metal elements other than Li and the additive elements) on the surface portion of the primary particle is usually
- the molar ratio is preferably 1 time or more, and the lower limit of the ratio is more preferably 1.05 times or more, more preferably 1.1 times or more, and particularly preferably 2 times or more.
- the upper limit is not particularly limited, but is preferably 500 times or less, more preferably 300 times or less, particularly preferably 100 times or less, and most preferably 50 times or less. If this ratio is too small, the effect of improving powder physical properties may be reduced, while if it is too large, battery performance may be deteriorated.
- the lithium transition metal based compound powder of the present invention is selected from the elements derived from the additive 2 of the present invention, that is, the 5th and 6th group elements of Group 5 to 7 on the surface portion of the primary particles. More preferably, at least one element (additive element 2 of the present invention) is present in a concentrated state.
- the molar ratio of the total amount of the additive element to the total of the metal elements other than Li and the additive element (that is, the metal element other than Li and the additive element) on the surface portion of the primary particle is usually The molar ratio is preferably 1 or more, and the lower limit of this ratio is preferably 1.05 or more, more preferably 1.1 or more, and particularly preferably 2 or more.
- the upper limit is not particularly limited, but is preferably 200 times or less, more preferably 100 times or less, particularly preferably 30 times or less, and most preferably 15 times or less. If this ratio is too small, the effect of improving powder physical properties may be reduced, while if it is too large, battery performance may be deteriorated.
- the composition of the surface part of the primary particles of the lithium transition metal compound powder is analyzed by, for example, X-ray photoelectron spectroscopy (XPS) using monochromatic light AlK ⁇ as the X-ray source, analysis area of 0.8 mm diameter, extraction angle It can be performed under the condition of 45 °.
- XPS X-ray photoelectron spectroscopy
- the range (depth) that can be analyzed varies depending on the composition of the primary particles, it is usually 0.1 nm to 50 nm, particularly 1 nm to 10 nm for a positive electrode active material. Therefore, in the present invention, the surface portion of the primary particles of the lithium transition metal-based compound powder indicates a measurable range under these conditions.
- the lithium transition metal-based compound powder of the present invention contains a lithium transition metal-based compound as a main component.
- the lithium transition metal-based compound powder of the present invention includes a lithium source and a transition metal source that are the main component raw materials, and at least one element selected from the group 16 elements in the structural formula of the third and subsequent periods (present book).
- the compound containing additive element 1) of the invention (hereinafter also referred to as “additive 1 of the present invention”) is obtained by pulverizing and mixing, followed by firing. Therefore, a compound containing an S atom in the structural formula is contained in the lithium transition metal compound.
- the additive element 1 of the present invention is not particularly limited as long as it is at least one element selected from Group 16 elements after the third period, but is selected from the group consisting of S, Se, Te, and Po. It is preferably at least one element, more preferably S or Se, and most preferably S in terms of being a light element.
- the compound having the above element promotes the growth of the active material particles by promoting the sintering between the primary particles or the secondary particles of the positive electrode active material at the time of high-temperature firing, thereby increasing the crystallization.
- the effect of obtaining a powder property having a high specific surface area is achieved.
- a lithium nickel manganese cobalt based composite oxide powder having a composition region defined by the composition formula (A) or (B) described below suitable for the present invention is pulverized as a main component material in a liquid medium at the same time.
- additive 1 of the present invention In the case of producing by a production method including spray-drying and firing a uniformly dispersed slurry, firing results at a high temperature result in higher density and reduction in specific surface area, and discharge capacity at a high current density is reduced. In other words, it is extremely difficult to improve both of them at the same time.
- a compound containing “additive element 1 of the present invention in the structural formula” (“additive 1 of the present invention”) is added. Then, it is possible to overcome this trade-off relationship by firing.
- the melting point of the additive 1 of the present invention as described above is not higher than the firing temperature and is characterized by melting but not solid solution during firing.
- the additive element 1 since the additive element 1 has an ionic radius smaller than that of the transition metal, it is considered that almost no element is substituted for the transition metal layer. Therefore, although acting as a sintering aid during firing, primary particles are formed without being solid-solved with the lithium transition metal composite oxide in the secondary particles. Therefore, although it is guessed that it has the effect of the present invention as described above, among these, it is preferable because it is available as an industrial raw material at a low cost and is a light element.
- the mechanism by which the specific compound added as the additive 1 of the present invention exhibits the effect of promoting grain growth and sintering during firing is not clear.
- the additive element 1 is added. Since the additive 1 contained exhibits an effect, it is different from any of the cation elements constituting the lithium transition metal compound, and is hardly dissolved by the solid phase reaction. As a result, the lithium transition metal compound It will be unevenly distributed on the surface or grain boundary of the particle. For this reason, it is presumed that the positive electrode active material particles acted in the direction of lowering the surface energy, and the growth and sintering of the particles were promoted. Moreover, the load characteristic of the battery is expected to be improved by lowering the powder volume resistance.
- the type of the additive 1 containing the additive element 1 of the present invention is not particularly limited as long as the effect of the present invention is exhibited, but as a compound having an S element, an inorganic salt is Me. (NH 4 ) x (SO 4 ) y ⁇ nH 2 O (Me is a cation element) is preferable.
- organic salts tetrabutylammonium hydrogen sulfate, trifluoromethanesulfonic acid, 1-naphthylamine-2-sulfonic acid, 1-naphthylamine-5-sulfonic acid, 1-naphthol-3,6-disulfonic acid, p- Bromobenzenesulfonic acid, p-anilinesulfonic acid, o-
- the amount of CO 2 generated during firing is small, and Na 2 SO 4 and Li 2 SO 4 are particularly preferable because they are industrially inexpensive and water-soluble.
- the compound having the Se elements oxides such as H 2 SeO 4, SeO 2, SeF 4, halogen compounds such as SeCl 2, such as oxy selenium chloride.
- an oxide is CO 2 , F 2 and the like are preferable because of a small amount of gas generation, SeO 2 is particularly preferable.
- the compound having a Te element include oxides such as TeO, TeO 2 , and H 2 TeO 3, and halides such as TeF 6 , TeCl 4 , and TeBr 4. 2 and F 2 are preferable because of a small amount of gas generation, TeO 2 is particularly preferable.
- these additives 1 may be used individually by 1 type, and may use 2 or more types together.
- the range of the additive 1 of the present invention is usually 0.001 mol% or more, preferably 0.01 mol% or more, more preferably 0.001 mol% or more based on the total weight of the raw materials constituting the main component. 1 mol% or more, more preferably 0.3 mol% or more, particularly preferably 0.5 mol% or more, and usually 10 mol% or less, preferably 5 mol% or less, more preferably 3 mol% or less, particularly preferably Is 2 mol% or less. If the lower limit is not reached, the above effects may not be obtained. If the upper limit is exceeded, battery performance may be reduced. *
- ⁇ Compound having additive element 2 of the present invention in the structural formula> in addition to the compound (additive element 1 of the present invention) containing at least one element (additive element 1 of the present invention) selected from the group 16 elements of the third and subsequent periods of the periodic table in the above structural formula
- a compound containing at least one element selected from Group 5 to 7 elements of Periodic Table 5th Period or 6th Period (Additive Element 2 of the present invention) (Additive of the present invention) 2) is used.
- the additive element 2 of the present invention is at least one element selected from the group consisting of Mo, W, Nb, Ta, and Re because of its great effect. Mo or W is more preferable, and W is most preferable.
- the type of the compound containing additive element 2 of the present invention is not particularly limited as long as it exhibits the effects of the present invention.
- An oxide is used.
- the additive element 2 is preferably at least one element selected from the group consisting of Mo, W, Nb, Ta, and Re.
- Exemplary compounds of Additive 2, the compound having a Mo element, MoO, MoO 2, MoO 3 , MoO x, include Mo 2 O 3, Mo 2 O 5, Li 2 MoO 4.
- Examples of the compound having W element include WO, WO 2 , WO 3 , H 2 WO 4 , WO x , W 2 O 3 , W 2 O 5 , W 18 O 49 , W 20 O 58 , W 24 O 70 , W 25 O 73 , W 40 O 118 , Li 2 WO 4 , ammonium metatungstate, and ammonium paratungstate.
- Examples of the compound having an Nb element include NbO, NbO 2 , Nb 2 O 3 , Nb 2 O 5 , Nb 2 O 5 .nH 2 O, and LiNbO 3 .
- Examples of the compound having Ta element include Ta 2 O, Ta 2 O 5 , and LiTaO 3 .
- Examples of the compound having the Re element include ReO 2 , ReO 3 , Re 2 O 3 , and Re 2 O 7 .
- ReO 2 , ReO 3 , Re 2 O 3 , and Re 2 O 7 are preferable, and WO 3 is particularly preferable because it is relatively easily available as an industrial raw material or includes lithium. It is done.
- These additives 2 may be used alone or in combination of two or more.
- the additive element 3 is preferably B from the viewpoint that it can be obtained at low cost as an industrial raw material and is a light element.
- additive 3 of the present invention The type of the compound containing additive element 3 of the present invention (hereinafter also referred to as “additive 3 of the present invention”) is not particularly limited as long as the effect of the present invention is exhibited.
- boric acid, oxo acid salts, oxides, hydroxides and the like are used.
- boric acid and oxide are preferable, and boric acid is particularly preferable because it can be obtained as an industrial raw material at low cost.
- Exemplary compounds of additive 3 of the present invention include BO, B 2 O 2 , B 2 O 3 , B 4 O 5 , B 6 O, B 7 O, B 13 O 2 , LiBO 2 , LiB 5 O 8 , Li 2 B 4 O 7 , HBO 2 , H 3 BO 3 , B (OH) 3 , B (OH) 4 , BiBO 3 , Bi 2 O 3 , Bi 2 O 5 , Bi (OH) 3, etc. From the viewpoint of being relatively inexpensive and easily available as an industrial raw material, B 2 O 3 , H 3 BO 3 and Bi 2 O 3 are preferable, and H 3 BO 3 is particularly preferable. These additives 3 may be used individually by 1 type, and 2 or more types may be mixed and used for them.
- the lower limit is usually the total molar amount of transition metal elements constituting the main component. 0.1 mol% or more, preferably 0.3 mol% or more, more preferably 0.5 mol% or more, particularly preferably 1.0 mol% or more, and the upper limit is usually 15 mol% or less, preferably 10 mol% % Or less, more preferably 5 mol% or less, particularly preferably 3 mol% or less. If the lower limit is not reached, the above effect may not be obtained. If the upper limit is exceeded, battery performance may be reduced.
- the median diameter of the lithium transition metal-based compound powder of the present invention is usually 1 ⁇ m or more, preferably 2.5 ⁇ m or more, more preferably 3 ⁇ m or more, further preferably 3.5 ⁇ m or more, most preferably 4 ⁇ m or more, and usually 50 ⁇ m or less. It is preferably 25 ⁇ m or less, more preferably 20 ⁇ m or less, still more preferably 18 ⁇ m or less, and most preferably 16 ⁇ m or less. If the median diameter is less than this lower limit, there is a possibility of causing a problem in applicability at the time of forming the positive electrode active material layer, and if it exceeds the upper limit, battery performance may be lowered.
- the 90% cumulative diameter (D 90 ) of the secondary particles of the lithium lithium transition metal compound powder of the present invention is usually 100 ⁇ m or less, preferably 50 ⁇ m or less, more preferably 25 ⁇ m or less, and most preferably 20 ⁇ m or less. It is 3 ⁇ m or more, preferably 4 ⁇ m or more, more preferably 5 ⁇ m or more, and most preferably 6 ⁇ m or more. If the 90% cumulative diameter (D 90 ) exceeds the above upper limit, the battery performance may be deteriorated, and if it is less than the lower limit, there is a possibility of causing a problem in the coating property when forming the positive electrode active material layer.
- the median diameter and 90% integrated diameter (D 90 ) as the average particle diameter are set to a refractive index of 1.60 by a known laser diffraction / scattering particle size distribution measuring apparatus, and the particle diameter standard is set. Measured as a volume reference. In this invention, it measured using 0.1 weight% sodium hexametaphosphate aqueous solution as a dispersion medium used in the case of a measurement.
- the average diameter (average primary particle diameter) of the lithium lithium transition metal compound powder of the present invention is not particularly limited, but the lower limit is preferably 0.1 ⁇ m or more, more preferably 0.2 ⁇ m or more, and most preferably
- the upper limit is preferably 3 ⁇ m or less, more preferably 2 ⁇ m or less, still more preferably 1.5 ⁇ m or less, and most preferably 1.2 ⁇ m or less. If the average primary particle size exceeds the above upper limit, it may adversely affect the powder filling property or the specific surface area will decrease, which may increase the possibility that the battery performance such as rate characteristics and output characteristics will decrease. There is sex. If the lower limit is not reached, there is a possibility that problems such as inferior reversibility of charge / discharge due to the undeveloped crystals.
- the average primary particle diameter in the present invention is an average diameter observed with a scanning electron microscope (SEM), and an average particle diameter of about 10 to 30 primary particles using a 10,000 times SEM image. It can be obtained as a value. *
- the lithium lithium transition metal compound powder of the present invention also has a BET specific surface area of usually 0.5 m 2 / g or more, preferably 0.6 m 2 / g or more, more preferably 0.7 m 2 / g or more, most Preferably it is 0.8 m 2 / g or more, usually 3 m 2 / g or less, preferably 2.8 m 2 / g or less, more preferably 2.5 m 2 / g or less, most preferably 2.3 m 2 / g or less. is there.
- the BET specific surface area is smaller than this range, the battery performance is likely to be lowered, and if it is larger, the bulk density is difficult to increase, and there is a possibility that a problem is likely to occur in the coating property when forming the positive electrode active material.
- the BET specific surface area can be measured with a known BET type powder specific surface area measuring device.
- an OMS Riken: AMS8000 type automatic powder specific surface area measuring device was used, nitrogen was used as an adsorption gas, and helium was used as a carrier gas.
- the powder sample was heated and deaerated with a mixed gas at a temperature of 150 ° C., then cooled to liquid nitrogen temperature to adsorb the mixed gas, and then heated to room temperature with water to be adsorbed. Nitrogen gas was desorbed, the amount was detected by a heat conduction detector, and the specific surface area of the sample was calculated therefrom. *
- the lithium transition metal-based compound powder for a lithium secondary battery positive electrode material of the present invention preferably satisfies a specific condition in measurement by a mercury intrusion method.
- the mercury intrusion method employed in the evaluation of the lithium transition metal compound powder of the present invention will be described below.
- the mercury intrusion method is a method for obtaining information such as specific surface area and pore diameter distribution from the relationship between pressure and the amount of mercury intruded into a pore of a sample such as porous particles while applying pressure. It is.
- the container containing the sample is evacuated and filled with mercury.
- Mercury has a high surface tension, and as it is, mercury does not enter the pores on the sample surface, but when pressure is applied to the mercury and the pressure is gradually increased, the pores increase in size from the smallest to the smallest. Gradually mercury enters the pores.
- a mercury intrusion curve representing the relationship between the pressure applied to mercury and the amount of mercury intruded can be obtained.
- the pore shape is cylindrical, the radius is r, the surface tension of mercury is ⁇ , and the contact angle is ⁇ , the size in the direction of pushing mercury out of the pore is ⁇ 2 ⁇ r ⁇ (cos ⁇ ). (If ⁇ > 90 °, this value is positive). Moreover, since the magnitude of the force in the direction of pushing mercury into the pores under the pressure P is expressed by ⁇ r 2 P, the following formulas (1) and (2) are derived from the balance of these forces. It will be.
- the size of the pore radius of the sample and its volume are calculated based on the obtained mercury intrusion curve.
- a pore distribution curve representing the relationship can be obtained. For example, when the pressure P is changed from 0.1 MPa to 100 MPa, the pores in the range from about 7500 nm to about 7.5 nm can be measured.
- the approximate measurement limit of the pore radius by the mercury intrusion method is that the lower limit is about 2 nm or more and the upper limit is about 200 ⁇ m or less, and the pores in a relatively large range compared to the nitrogen adsorption method described later. It can be said that it is suitable for analysis of distribution.
- Measurement by the mercury intrusion method can be performed using an apparatus such as a mercury porosimeter. Specific examples of the mercury porosimeter include an autopore manufactured by Micromeritics, a pore master manufactured by Quantachrome, and the like.
- the lithium transition metal based compound powder of the present invention has a mercury intrusion amount of 0.1 cm 3 / g or more and 1.0 cm 3 /1.0 in a mercury intrusion curve by a mercury intrusion method at a pressure from 3.86 kPa to 413 MPa. g or less is preferable. More preferably, the lower limit of mercury intrusion is usually 0.1 cm 3 / g or more, more preferably 0.15 cm 3 / g or more, most preferably 0.2 cm 3 / g or more, more preferably 0.9 cm. 3 / g or less, more preferably 0.8 cm 3 / g or less, and most preferably not more than 0.7 cm 3 / g.
- the specific main peak described below usually appears when the pore distribution curve is measured by the mercury intrusion method described above.
- the “pore distribution curve” refers to the total pore volume per unit weight (usually 1 g) of pores having a radius equal to or larger than the radius of the pores on the horizontal axis, A value obtained by differentiating the logarithm of the pore radius is plotted on the vertical axis, and is usually expressed as a graph connecting the plotted points.
- the pore distribution curve obtained by measuring the lithium transition metal-based compound powder of the present invention by mercury porosimetry is referred to as “the pore distribution curve according to the present invention” as appropriate in the following description.
- peak 1 refers to a peak appearing at 80 nm or more and less than 800 nm (pore radius) in the pore distribution curve
- peak 2 refers to 800 nm or more in the pore distribution curve ( The peak appearing in the pore radius).
- peak top refers to the point at which the coordinate value of the vertical axis takes the largest value in each peak of the pore distribution curve.
- Peak 1 of the pore distribution curve according to the present invention has a peak top whose pore radius is usually 80 nm or more, more preferably 90 nm or more, most preferably 100 nm or more, and usually 800 nm or less, preferably 750 nm or less, More preferably, it exists in 700 nm or less, More preferably, it is 650 nm or less, Most preferably, it exists in the range of 600 nm or less.
- the peak 1 of the pore distribution curve according to the present invention preferably has a pore volume of usually 0.01 cm 3 / g or more, preferably 0.02 cm 3 / g or more, more preferably 0.00.
- 03cm 3 / g or more most preferably 0.04 cm 3 / g or more and usually 0.2 cm 3 / g or less, preferably 0.15 cm 3 / g or less, more preferably 0.1 cm 3 / g or less, most Preferably it is 0.08 cm ⁇ 3 > / g or less.
- the pore distribution curve by the mercury intrusion method has at least one peak 2 having a peak top at a pore radius of 800 nm or more and 4000 nm or less, and a pore radius of 80 nm or more and less than 800 nm.
- a lithium transition metal compound powder for a lithium secondary battery positive electrode material having a peak 1 in which a peak top is present is preferable.
- the pore distribution curve according to the present invention may have a plurality of peaks in addition to the above-described peak 1, and in particular, a peak having a peak top within a pore radius range of 800 nm or more and 4000 nm or less. 2 is preferable.
- Peak 2 of the pore distribution curve according to the present invention has a peak top whose pore radius is usually 800 nm or more, more preferably 900 nm or more, most preferably 1000 nm or more, and usually 4000 nm or less, preferably 3600 nm or less, More preferably, it exists in 3400 nm or less, More preferably, it is 3200 nm or less, Most preferably, it exists in the range of 3000 nm or less. When the upper limit of this range is exceeded, when a battery is made using the lithium transition metal compound powder of the present invention as the positive electrode material, lithium diffusion in the positive electrode material is inhibited, or the conductive path is insufficient, resulting in load characteristics. May be reduced.
- the pore volume of the peak having a peak top at a pore radius of 800 nm or more and 4000 nm or less is preferably usually 0.1 cm 3 / g or more, preferably 0. .15cm 3 / g or more, more preferably 0.20 cm 3 / g or more, most preferably 0.25 cm 3 / g or more and usually 0.5 cm 3 / g or less, preferably 0.45 cm 3 / g or less, more preferably 0.4 cm 3 / g or less, and most preferably not more than 0.35 cm 3 / g.
- the bulk density of the lithium transition metal-based compound powder of the present invention is usually 1.2 g / cm 3 or more, preferably 1.3 g / cm 3 or more, more preferably 1.4 g / cm 3 or more, and most preferably 1.5 g. / Cm 3 or more, usually 2.8 g / cm 3 or less, preferably 2.7 g / cm 3 or less, more preferably 2.6 g / cm 3 or less, and most preferably 2.5 g / cm 3 or less. It is preferable for the bulk density to exceed this upper limit for improving powder filling properties and electrode density, but the specific surface area may be too low, and battery performance may be reduced. When the bulk density is lower than this lower limit, there is a possibility of adversely affecting the powder filling property and electrode preparation.
- the bulk density is 5 to 10 g of lithium transition metal compound powder in a 10 ml glass graduated cylinder and tapped 200 times with a stroke of about 20 mm (tap density) g / Calculate as cc. *
- the lithium transition metal-based compound powder of the present invention preferably has at least a lithium nickel manganese cobalt-based composite oxide having a layered structure and / or a lithium manganese-based composite oxide having a spinel structure as a main component.
- the main component is a lithium nickel manganese cobalt composite oxide having a layered structure.
- lithium nickel manganese cobalt-based composite oxides lithium nickel manganese-based composite oxides not containing cobalt are also included in the term “lithium nickel manganese cobalt-based composite oxide”.
- the layered structure will be described in more detail.
- a typical crystal system having a layered structure there are those belonging to the ⁇ -NaFeO 2 type such as LiCoO 2 and LiNiO 2 , and these are hexagonal systems.
- layered R ( ⁇ 3) m structure (Hereinafter sometimes referred to as “layered R ( ⁇ 3) m structure”).
- the layered LiMeO 2 is not limited to the layered R ( ⁇ 3) m structure.
- LiMnO 2 called so-called layered Mn is an orthorhombic layered compound of the space group Pm2m
- Li 2 MnO 3 called so-called 213 phase is Li [Li 1/3 Mn 2/3 ].
- O 2 which is a monoclinic space group C2 / m structure, is also a layered compound in which a Li layer, a [Li 1/3 Mn 2/3 ] layer, and an oxygen layer are stacked.
- the spinel structure will be described in more detail.
- a typical crystal system having a spinel structure there is a crystal system belonging to the MgAl 2 O 4 type such as LiMn 2 O 4 , which is a cubic system, and because of its symmetry, the space group.
- spinel-type Fd ( ⁇ 3) m structure (Hereinafter sometimes referred to as “spinel-type Fd ( ⁇ 3) m structure”).
- the spinel type LiMeO 4 is not limited to the spinel type Fd ( ⁇ 3) m structure.
- spinel-type LiMeO 4 belonging to a different space group (P4 3 32) also exists.
- the lithium-containing transition metal compound powder of the present invention is preferably a lithium transition metal compound powder represented by the following composition formula (A) or (B). Further, in the layered compound, the elution amount of Mn is relatively small as compared with the spinel type compound, and the influence of Mn on the cycle characteristics is small, so that the effect of the present invention appears as a clear difference. Therefore, it is more preferable that the present invention is a lithium transition metal compound powder represented by the following composition formula (A).
- x is usually 0 or more, preferably 0.01 or more, more preferably 0.02 or more, most preferably 0.03 or more, usually 0.5 or less, preferably 0.4 or less, Preferably it is 0.3 or less, most preferably 0.2 or less.
- M is an element composed of Li, Ni, and Mn, or Li, Ni, Mn, and Co. Further, the Mn / Ni molar ratio is usually 0.1 or more, preferably 0.3 or more, more preferably 0.5 or more, still more preferably 0.6 or more, still more preferably 0.7 or more, still more preferably 0.
- the Co / (Mn + Ni + Co) molar ratio is usually 0 or more, preferably 0.01 or more, more preferably 0.02 or more, still more preferably 0.03 or more, most preferably 0.05 or more, usually 0.35 or less, preferably Is 0.20 or less, more preferably 0.15 or less, still more preferably 0.10 or less, and most preferably 0.099 or less.
- the Li molar ratio in M is usually 0.001 or more, preferably 0.01 or more, more preferably 0.02 or more, further preferably 0.03 or more, most preferably 0.05 or more, usually 0.2 or less, Preferably it is 0.19 or less, More preferably, it is 0.18 or less, More preferably, it is 0.17 or less, Most preferably, it is 0.15 or less.
- the atomic ratio of the oxygen amount is described as 2 for convenience, but there may be some non-stoichiometry.
- the atomic ratio of oxygen is usually in the range of 2 ⁇ 0.2, preferably in the range of 2 ⁇ 0.15, more preferably in the range of 2 ⁇ 0.12, and even more preferably 2 ⁇ 0.10. And particularly preferably in the range of 2 ⁇ 0.05.
- the lithium transition metal-based compound powder of the present invention is preferably fired by performing high-temperature firing in an oxygen-containing gas atmosphere in order to increase the crystallinity of the positive electrode active material.
- the lower limit of the firing temperature is usually 1000 ° C. or higher, preferably 1010 ° C. or higher, more preferably 1025 ° C. or higher, most preferably in the lithium nickel manganese cobalt composite oxide having the composition represented by the composition formula (A).
- the upper limit is 1250 ° C. or lower, preferably 1200 ° C. or lower, more preferably 1175 ° C. or lower, and most preferably 1150 ° C. or lower.
- the firing temperature is too low, heterogeneous phases are mixed, and the lattice distortion increases without developing a crystal structure. Moreover, the specific surface area becomes too large. Conversely, if the firing temperature is too high, the primary particles grow excessively, sintering between the particles proceeds too much, and the specific surface area becomes too small. *
- M ′ is at least one of transition metals selected from Ni, Cr, Fe, Co and Cu, and among these, Ni is most preferable from the viewpoint of charge / discharge capacity at a high potential.
- the value of a is usually 0 or more, preferably 0.01 or more, more preferably 0.02 or more, further preferably 0.03 or more, most preferably 0.04 or more, usually 0.3 or less, preferably 0.2. Below, more preferably 0.15 or less, still more preferably 0.1 or less, and most preferably 0.075 or less.
- the value of a is within this range, the energy density per unit weight in the lithium transition metal-based compound is not significantly impaired, and good load characteristics can be obtained, which is preferable.
- the value of b is usually 0.4 or more, preferably 0.425 or more, more preferably 0.45 or more, further preferably 0.475 or more, most preferably 0.49 or more, usually 0.6 or less, preferably 0. .575 or less, more preferably 0.55 or less, still more preferably 0.525 or less, and most preferably 0.51 or less. If the value of b is in this range, the energy density per unit weight in the lithium transition metal compound is high, which is preferable.
- the value of ⁇ is usually in the range of ⁇ 0.5, preferably in the range of ⁇ 0.4, more preferably in the range of ⁇ 0.2, still more preferably in the range of ⁇ 0.1, particularly preferably ⁇ 0.05. Range. If the value of ⁇ is within this range, the stability as a crystal structure is high, and the cycle characteristics and high-temperature storage of a battery having an electrode produced using this lithium transition metal compound are favorable.
- each transition metal and lithium are analyzed by an inductively coupled plasma emission spectrometer (ICP-AES) to obtain a ratio of Li / Ni / Mn. It is calculated by the thing. From a structural point of view, it is considered that lithium related to a is substituted for the same transition metal site.
- ICP-AES inductively coupled plasma emission spectrometer
- the reason why the lithium transition metal compound powder of the present invention brings about the above-described effect is considered as follows. If a compound having a temperature lower than the firing temperature of the active material is present in the system during firing of the active material, it is presumed that the movement of primary particles during firing is simplified and the bulk density is increased. However, since the SSA decreases as the primary particles become larger, it is important to fire without causing the primary particles to grow. It is presumed that the additive 1 of the present invention has an effect of making primary particles move easily without causing growth of primary particles during firing and increasing the bulk density.
- the lithium transition metal-based compound powder of the present invention maintains a spherical shape of the crystal secondary particles and has a large specific surface area without reducing the bulk density.
- the lithium transition metal-based compound powder of the present invention maintains a spherical shape of the crystal secondary particles and has a large specific surface area without reducing the bulk density.
- it also has a surface state that improves load characteristics, and has an excellent characteristic balance and powder handleability as a positive electrode active material. It is estimated that it was achieved.
- the specific surface area becomes small.
- the specific surface area can be increased without reducing the bulk density by mixing the compound having S atoms, the Li raw material, and the transition metal raw material and firing at a high temperature. Therefore, it has been clarified that the present invention is effective particularly in the charge / discharge test at a high current density.
- the compound which has the additive element 1 and the additive element 2 of this invention exists in an active material, it can estimate that Li ion conductivity or electronic conductivity improves, and the load characteristic of a battery improves.
- the method for producing the lithium transition metal compound powder of the present invention is not limited to a specific production method, but the lithium compound, at least one transition metal compound selected from Mn, Co and Ni, A slurry preparation step for obtaining a slurry in which the additive of the invention is pulverized in a liquid medium and uniformly dispersed therein, a spray drying step for spray-drying the obtained slurry, and a firing of the obtained spray-dried body It is preferably manufactured by a manufacturing method including a firing step.
- a lithium nickel manganese cobalt based composite oxide powder will be described as an example.
- a slurry in which a lithium compound, a nickel compound, a manganese compound, a cobalt compound, and the additive of the present invention are dispersed in a liquid medium is spray-dried.
- the spray-dried product obtained in this manner can be produced by firing in an oxygen-containing gas atmosphere.
- the method for producing a lithium transition metal-based compound powder of the present invention will be described in detail by taking as an example the method for producing a lithium nickel manganese cobalt-based composite oxide powder that is a preferred embodiment of the present invention.
- the lithium compounds include Li 2 CO 3 , LiNO 3 , LiNO 2 , LiOH, and LiOH ⁇ H 2.
- Examples include O, LiH, LiF, LiCl, LiBr, LiI, CH 3 OOLi, Li 2 O, Li 2 SO 4 , dicarboxylic acid Li, citric acid Li, fatty acid Li, and alkyl lithium.
- lithium compounds that do not contain nitrogen, sulfur, or halogen atoms are preferred because they do not generate harmful substances such as SO x and NO x during the firing treatment.
- Li 2 CO 3 LiOH, LiOH.H 2 O is preferable, and Li 2 CO 3 is particularly preferable. These lithium compounds may be used alone or in combination of two or more.
- Ni (OH) 2 , NiO, NiOOH, NiCO 3 , 2NiCO 3 .3Ni (OH) 2 .4H 2 O, NiC are used in that no harmful substances such as SO X and NO X are generated during the firing process.
- Nickel compounds such as 2 O 4 .2H 2 O are preferred.
- Ni (OH) 2 , NiO, NiOOH, NiCO 3 from the viewpoint that it can be obtained as an industrial raw material at a low cost and from the viewpoint of high reactivity, Ni (OH) 2 , NiO, NiOOH, NiCO 3 , and further, a decomposition gas is generated at the time of firing.
- Ni (OH) 2 , NiOOH, and NiCO 3 are particularly preferable from the viewpoint of easily forming voids in the secondary particles.
- These nickel compounds may be used alone or in combination of two or more.
- manganese compounds such as Mn 2 O 3 , MnO 2 , Mn 3 O 4 , manganese oxide, MnCO 3 , Mn (NO 3 ) 2 , MnSO 4 , manganese acetate, manganese dicarboxylate, manganese citrate, fatty acid manganese And manganese salts such as oxyhydroxide, manganese chloride and the like.
- MnO 2 , Mn 2 O 3 , Mn 3 O 4 , and MnCO 3 do not generate gases such as SO X and NO X during firing, and can be obtained at low cost as industrial raw materials. Therefore, it is preferable.
- These manganese compounds may be used individually by 1 type, and may use 2 or more types together.
- Co (OH) 2 , CoOOH, CoO, Co 2 O 3 , Co 3 O 4 , and CoCO 3 are preferable, and more preferably, from the viewpoint that no harmful substances such as SO X and NO X are generated during the firing process.
- Co (OH) 2 and CoOOH are industrially inexpensively available and highly reactive.
- Co (OH) 2 , CoOOH, and CoCO 3 are particularly preferable from the viewpoint of easily forming voids in the secondary particles of the spray-dried powder by generating decomposition gas during firing.
- These cobalt compounds may be used individually by 1 type, and may use 2 or more types together.
- the additive of the present invention is as described above.
- the method for mixing the raw materials is not particularly limited, and may be wet or dry.
- a method using an apparatus such as a ball mill, a vibration mill, or a bead mill can be used.
- Wet mixing in which the raw material compound is mixed in a liquid medium such as water or alcohol is preferable because more uniform mixing is possible and the reactivity of the mixture can be increased in the firing step.
- the mixing time varies depending on the mixing method, but it is sufficient that the raw materials are uniformly mixed at the particle level.
- a ball mill usually takes about 1 to 2 days
- a bead mill (wet continuous method) has a residence time. Is usually about 0.1 to 6 hours.
- the raw material is pulverized in parallel.
- the particle diameter of the raw material particles after pulverization is an index, but the average particle diameter (median diameter) is usually 0.6 ⁇ m or less, preferably 0.55 ⁇ m or less, more preferably 0.52 ⁇ m or less, most preferably Preferably, it is 0.5 ⁇ m or less.
- the average particle size of the pulverized raw material particles is too large, the reactivity in the firing process is lowered and the composition is difficult to be uniformized.
- making particles smaller than necessary leads to an increase in pulverization cost, so that the average particle size is usually 0.01 ⁇ m or more, preferably 0.02 ⁇ m or more, more preferably 0.05 ⁇ m or more. It ’s fine.
- a means for realizing such a degree of pulverization is not particularly limited, but a wet pulverization method is preferable. Specific examples include dyno mill.
- the median diameter of the pulverized particles in the slurry was measured with a known laser diffraction / scattering type particle size distribution measuring apparatus with a refractive index of 1.24 and a particle diameter standard set as a volume standard. Is.
- a 0.1 wt% sodium hexametaphosphate aqueous solution was used as a dispersion medium used in the measurement, and measurement was performed after 5 minutes of ultrasonic dispersion (output 30 W, frequency 22.5 kHz).
- the drying method is not particularly limited, but spray drying is preferable from the viewpoints of uniformity of the generated particulate matter, powder flowability, powder handling performance, and efficient production of dry particles.
- a slurry obtained by wet pulverizing the raw material compound and the additive of the present invention is spray-dried.
- a powder obtained by agglomerating primary particles to form secondary particles is obtained.
- the spray-dried powder formed by agglomerating primary particles to form secondary particles is a geometric feature of the spray-dried powder of the present invention. Examples of the shape confirmation method include SEM observation and cross-sectional SEM observation.
- the median diameter of the powder obtained by spray drying which is also a firing precursor of lithium transition metal based compound powder such as lithium nickel manganese cobalt based composite oxide powder of the present invention (in this case, measured without applying ultrasonic dispersion)
- the value is usually 25 ⁇ m or less, more preferably 20 ⁇ m or less, still more preferably 18 ⁇ m or less, and most preferably 16 ⁇ m or less.
- it is usually 3 ⁇ m or more, preferably 4 ⁇ m or more, more preferably 5 ⁇ m or more.
- the particle size can be controlled by appropriately selecting the spray format, the pressurized gas flow supply rate, the slurry supply rate, the drying temperature, and the like. *
- a lithium compound, a nickel compound, a manganese compound, and a slurry in which a cobalt compound and the additive of the present invention are dispersed in a liquid medium are spray-dried, and the obtained powder is fired to obtain lithium nickel manganese cobalt
- V (cP) the slurry viscosity during spray drying
- S (L / min) the slurry supply amount
- G (L / min) the slurry viscosity Spray drying is performed under conditions where V is 50 cP ⁇ V ⁇ 7000 cP and the gas-liquid ratio G / S is 500 ⁇ G / S ⁇ 10000.
- the slurry viscosity V (cP) is usually 50 cP or more as a lower limit, preferably 100 cP or more, more preferably 300 cP or more, most preferably 500 cP, and the upper limit is usually 7000 cp or less, preferably 6500 cp or less. Is 5500 cp or less, most preferably 5000 cp or less.
- the gas-liquid ratio G / S is usually 500 or more, preferably 800 or more, more preferably 1000 or more, most preferably 1500 or more as the lower limit, and usually 10,000 or less, preferably 9000 or less, as the upper limit. Preferably it is 8000 or less, most preferably 7500 or less.
- the slurry supply amount S and the gas supply amount G are appropriately set according to the viscosity of the slurry used for spray drying, the specifications of the spray drying apparatus used, and the like.
- the above-mentioned gas-liquid ratio G / S is satisfied by controlling the slurry supply amount and gas supply amount that meet the above-mentioned slurry viscosity V (cP) and that are suitable for the specifications of the spray drying apparatus to be used.
- Spray drying may be performed within a range, and other conditions are appropriately set according to the type of apparatus to be used, but it is preferable to select the following conditions. *
- spray drying of the slurry is usually 50 ° C. or higher, preferably 70 ° C. or higher, more preferably 120 ° C. or higher, most preferably 140 ° C. or higher, usually 300 ° C. or lower, preferably 250 ° C. or lower, more preferably 200 ° C. It is preferable to carry out the reaction at a temperature of °C or less, most preferably 180 °C or less. If this temperature is too high, the resulting granulated particles may have a lot of hollow structures, which may reduce the packing density of the powder. On the other hand, if it is too low, problems such as powder sticking and blockage due to moisture condensation at the powder outlet may occur.
- the “firing precursor” means a precursor of a lithium transition metal compound such as a lithium nickel manganese cobalt composite oxide before firing obtained by treating a spray-dried powder.
- the above spray-dried powder may contain a compound that generates or sublimates a decomposition gas during the above-described firing to form voids in the secondary particles, and serves as a firing precursor.
- the firing temperature is usually 1000 ° C. or higher, preferably 1010 ° C. or higher, more preferably 1025 ° C. or higher, most preferably 1050 ° C. or higher, usually 1250 ° C. or lower, preferably 1200 ° C. or lower, more preferably 1175 ° C. or lower. Most preferably, it is 1150 degrees C or less.
- a box furnace, a tubular furnace, a tunnel furnace, a rotary kiln or the like can be used.
- the firing process is usually divided into three parts: temperature increase, maximum temperature retention, and temperature decrease.
- the second maximum temperature holding portion is not necessarily limited to one time, and may include two or more stages depending on the purpose, which means that aggregation is eliminated to the extent that secondary particles are not destroyed.
- the temperature raising, maximum temperature holding, and temperature lowering steps may be repeated twice or more with a crushing step or a crushing step meaning crushing to primary particles or even fine powder.
- the first stage is preferably maintained at a temperature not lower than the temperature at which the Li raw material begins to decompose and below the melting temperature.
- the first stage is preferably maintained at 400 ° C. or higher. More preferably, it is 450 ° C. or higher, more preferably 500 ° C. or higher, most preferably 550 ° C. or higher, usually 850 ° C. or lower, more preferably 800 ° C. or lower, more preferably 780 ° C. or lower, most preferably 750 ° C. or lower. is there.
- the temperature in the furnace is usually raised at a temperature raising rate of 1 ° C./min to 15 ° C./min. Even if this rate of temperature rise is too slow, it takes time and is industrially disadvantageous. However, if it is too fast, the furnace temperature does not follow the set temperature depending on the furnace.
- the rate of temperature rise is preferably 2 ° C./min or more, more preferably 3 ° C./min or more, preferably 20 ° C./min or less, more preferably 18 ° C./min or less.
- the holding time in the maximum temperature holding step varies depending on the temperature, it is usually 15 minutes or longer, preferably 30 minutes or longer, more preferably 45 minutes or longer, most preferably 1 hour or longer within the above-mentioned temperature range. Time or less, preferably 12 hours or less, more preferably 9 hours or less, and most preferably 6 hours or less. If the firing time is too short, it becomes difficult to obtain a lithium transition metal-based compound powder with good crystallinity, and it is not practical to be too long. If the firing time is too long, it will be disadvantageous because it will be necessary to crush afterwards or it will be difficult to crush.
- the temperature in the furnace is normally decreased at a temperature decreasing rate of 0.1 ° C./min to 15 ° C./min. If the temperature lowering rate is too slow, it takes time and is industrially disadvantageous, but if it is too fast, the uniformity of the target product tends to be lost or the deterioration of the container tends to be accelerated.
- the temperature lowering rate is preferably 1 ° C./min or more, more preferably 3 ° C./min or more, preferably 20 ° C./min or less, more preferably 15 ° C./min or less.
- the atmosphere during firing has an appropriate oxygen partial pressure region depending on the composition of the lithium transition metal-based compound powder to be obtained, various appropriate gas atmospheres for satisfying it are used.
- the gas atmosphere include oxygen, air, nitrogen, argon, hydrogen, carbon dioxide, and a mixed gas thereof.
- An oxygen-containing gas atmosphere such as air can be used for the lithium nickel manganese cobalt based composite oxide powder specifically implemented in the present invention.
- the atmosphere has an oxygen concentration of 1% by volume or more, preferably 10% by volume or more, more preferably 15% by volume or more, and 100% by volume or less, preferably 50% by volume or less, more preferably 25% by volume or less.
- the production conditions are constant.
- the target Li is adjusted by adjusting the mixing ratio of each compound. The molar ratio of / Ni / Mn / Co can be controlled.
- the capacity is high, the low-temperature output characteristics and the storage characteristics are excellent, and the performance balance is high.
- a positive electrode material for a lithium secondary battery is provided.
- the positive electrode for a lithium secondary battery of the present invention is obtained by forming a positive electrode active material layer containing a lithium transition metal compound powder for a lithium secondary battery positive electrode material of the present invention and a binder on a current collector. It is.
- the positive electrode active material layer is usually formed by mixing a positive electrode material, a binder, and a conductive material and a thickener, which are used if necessary, in a dry form into a sheet shape, and then pressing the positive electrode current collector on the positive electrode current collector. Alternatively, these materials are dissolved or dispersed in a liquid medium to form a slurry, which is applied to the positive electrode current collector and dried. *
- metal materials such as aluminum, stainless steel, nickel plating, titanium and tantalum, and carbon materials such as carbon cloth and carbon paper are usually used. Of these, metal materials are preferable, and aluminum is particularly preferable.
- shape in the case of a metal material, a metal foil, a metal cylinder, a metal coil, a metal plate, a metal thin film, an expanded metal, a punch metal, a foam metal, etc., and in the case of a carbon material, a carbon plate, a carbon thin film, a carbon cylinder Etc.
- metal thin films are preferable because they are currently used in industrialized products. In addition, you may form a thin film suitably in mesh shape. *
- the positive electrode current collector When a thin film is used as the positive electrode current collector, its thickness is arbitrary, but it is usually 1 ⁇ m or more, preferably 3 ⁇ m or more, more preferably 5 ⁇ m or more, and usually 100 mm or less, preferably 1 mm or less, more preferably 50 ⁇ m or less.
- the range of is preferable. If it is thinner than the above range, the strength required for the current collector may be insufficient. On the other hand, if it is thicker than the above range, the handleability may be impaired. *
- the binder used in the production of the positive electrode active material layer is not particularly limited, and in the case of a coating method, any material that is stable with respect to the liquid medium used during electrode production may be used.
- Specific examples include polyethylene, Resin polymers such as polypropylene, polyethylene terephthalate, polymethyl methacrylate, aromatic polyamide, cellulose, nitrocellulose, SBR (styrene butadiene rubber), NBR (acrylonitrile butadiene rubber), fluorine rubber, isoprene rubber, butadiene rubber, ethylene ⁇ Rubber polymers such as propylene rubber, styrene / butadiene / styrene block copolymers and hydrogenated products thereof, EPDM (ethylene / propylene / diene terpolymers), styrene / ethylene / butadiene / ethylene copolymers, Styrene and isoprene styrene Thermoplastic elastomeric poly
- Soft resin-like polymers fluorinated polymers such as polyvinylidene fluoride, polytetrafluoroethylene, fluorinated polyvinylidene fluoride, polytetrafluoroethylene / ethylene copolymers, ion conductivity of alkali metal ions (especially lithium ions) And the like.
- these substances may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.
- the ratio of the binder in the positive electrode active material layer is usually 0.1% by weight or more, preferably 1% by weight or more, more preferably 5% by weight or more, and usually 80% by weight or less, preferably 60% by weight or less. More preferably, it is 40% by weight or less, and most preferably 10% by weight or less. If the proportion of the binder is too low, the positive electrode active material cannot be sufficiently retained and the positive electrode has insufficient mechanical strength, which may deteriorate battery performance such as cycle characteristics. Battery capacity and conductivity may be reduced. *
- the positive electrode active material layer usually contains a conductive material in order to increase conductivity.
- a conductive material there are no particular restrictions on the type, but specific examples include metal materials such as copper and nickel, graphite such as natural graphite and artificial graphite, carbon black such as acetylene black, and amorphous carbon such as needle coke. And carbon materials. In addition, these substances may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.
- the proportion of the conductive material in the positive electrode active material layer is usually 0.01% by weight or more, preferably 0.1% by weight or more, more preferably 1% by weight or more, and usually 50% by weight or less, preferably 30%. % By weight or less, more preferably 20% by weight or less. If the proportion of the conductive material is too low, the conductivity may be insufficient, and conversely if it is too high, the battery capacity may be reduced. *
- a liquid medium for forming a slurry it is possible to dissolve or disperse a lithium transition metal compound powder as a positive electrode material, a binder, and a conductive material and a thickener used as necessary. If it is a solvent, there is no restriction
- organic solvent examples include N-methylpyrrolidone (NMP), dimethylformamide, dimethylacetamide, methyl ethyl ketone, cyclohexanone, methyl acetate, methyl acrylate, diethyltriamine, N , N-dimethylaminopropylamine, ethylene oxide, tetrahydrofuran (THF), toluene, acetone, dimethyl ether, dimethylacetamide, hexamethylphosphalamide, dimethyl sulfoxide, benzene, xylene, quinoline, pyridine, methylnaphthalene, hexane, etc. be able to.
- NMP N-methylpyrrolidone
- dimethylformamide dimethylacetamide
- methyl ethyl ketone cyclohexanone
- methyl acetate methyl acrylate
- diethyltriamine N , N-dimethylaminopropylamine
- a dispersant is added together with the thickener, and a slurry such as SBR is slurried.
- these solvents may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.
- the content of the lithium transition metal-based compound powder of the present invention as the positive electrode material in the positive electrode active material layer is usually 10% by weight or more, preferably 30% by weight or more, more preferably 50% by weight or more, and usually 99%. .9% by weight or less, preferably 99% by weight or less. If the proportion of the lithium transition metal compound powder in the positive electrode active material layer is too large, the strength of the positive electrode tends to be insufficient, and if it is too small, the capacity may be insufficient. *
- the thickness of the positive electrode active material layer is usually about 10 to 200 ⁇ m.
- the lower limit is usually 2.2 g / cm 3 or more, preferably 2.4 g / cm 3 or more, particularly preferably 2.6 g / cm 3 or more
- the upper limit is usually , 4.2 g / cm 3 or less, preferably 4.0 g / cm 3 or less, particularly preferably 3.8 g / cm 3 or less.
- the positive electrode active material layer obtained by coating and drying is preferably consolidated by a roller press or the like in order to increase the packing density of the positive electrode active material.
- the positive electrode for a lithium secondary battery of the present invention can be prepared.
- the lithium secondary battery of the present invention includes the above-described positive electrode for a lithium secondary battery of the present invention capable of occluding and releasing lithium, a negative electrode capable of occluding and releasing lithium, and a non-aqueous electrolyte using a lithium salt as an electrolytic salt. Is provided. Further, a separator for holding a non-aqueous electrolyte may be provided between the positive electrode and the negative electrode. In order to effectively prevent a short circuit due to contact between the positive electrode and the negative electrode, it is desirable to interpose a separator in this way.
- the negative electrode is usually configured by forming a negative electrode active material layer on a negative electrode current collector, similarly to the positive electrode.
- a material of the negative electrode current collector a metal material such as copper, nickel, stainless steel, nickel-plated steel, or a carbon material such as carbon cloth or carbon paper is used.
- a metal material a metal foil, a metal cylinder, a metal coil, a metal plate, a metal thin film, etc.
- a carbon material, a carbon plate, a carbon thin film, a carbon cylinder, etc. are mentioned.
- metal thin films are preferable because they are currently used in industrialized products.
- the preferred thickness range is the same as the range described above for the positive electrode current collector.
- the negative electrode active material layer includes a negative electrode active material.
- the negative electrode active material is not particularly limited as long as it can electrochemically occlude and release lithium ions, but it can usually occlude and release lithium from the viewpoint of high safety.
- a carbon material is used. Although there is no restriction
- carbon materials obtained by partially graphitizing these furnace black, acetylene black, pitch-based carbon fibers, and the like.
- graphite is preferable, and particularly preferable is artificial graphite, purified natural graphite, or graphite material containing pitch in these graphites manufactured by subjecting easy-graphite pitch obtained from various raw materials to high-temperature heat treatment. Therefore, those subjected to various surface treatments are mainly used.
- One of these carbon materials may be used alone, or two or more thereof may be used in combination.
- the d-value (interlayer distance: d 002 ) of the lattice plane (002 plane) determined by X-ray diffraction by the Gakushin method is usually 0.335 nm or more, and usually 0.34 nm. In the following, it is preferable that the thickness is 0.337 nm or less. Further, the ash content of the graphite material is usually 1% by weight or less, particularly 0.5% by weight or less, and particularly preferably 0.1% by weight or less, based on the weight of the graphite material.
- the crystallite size (Lc) of the graphite material determined by X-ray diffraction by the Gakushin method is usually 30 nm or more, preferably 50 nm or more, and particularly preferably 100 nm or more.
- the median diameter of the graphite material determined by the laser diffraction / scattering method is usually 1 ⁇ m or more, especially 3 ⁇ m or more, more preferably 5 ⁇ m or more, particularly 7 ⁇ m or more, and usually 100 ⁇ m or less, especially 50 ⁇ m or less, more preferably 40 ⁇ m or less, especially 40 ⁇ m or less. It is preferable that it is 30 micrometers or less.
- the BET specific surface area of the graphite material is usually 0.5 m 2 / g or more, preferably 0.7 m 2 / g or more, more preferably 1.0 m 2 / g or more, and further preferably 1.5 m 2 / g. or more, and usually 25.0 m 2 / g or less, preferably 20.0 m 2 / g, more preferably 15.0 m 2 / g or less, still more preferably 10.0 m 2 / g or less.
- intensity ratio I a / I B of the intensity I B of a peak P B is what is preferably 0 to 0.5.
- the half width of the peak P A is preferably 26cm -1 or less, 25 cm -1 or less is more preferable.
- negative electrode active material of other materials capable of inserting and extracting lithium.
- negative electrode active materials other than carbon materials include metal oxides such as tin oxide and silicon oxide, nitrides such as Li 2.6 Co 0.4 N, lithium alloys such as lithium alone and lithium aluminum alloys, and the like. Can be mentioned.
- metal oxides such as tin oxide and silicon oxide
- nitrides such as Li 2.6 Co 0.4 N
- lithium alloys such as lithium alone and lithium aluminum alloys, and the like.
- One of these materials other than the carbon material may be used alone, or two or more thereof may be used in combination. Moreover, you may use in combination with the above-mentioned carbon material.
- the negative electrode active material layer is usually prepared by slurrying the above-described negative electrode active material, a binder, and optionally a conductive material and a thickener in a liquid medium. It can manufacture by apply
- the liquid medium, the binder, the thickener, the conductive material, and the like that form the slurry the same materials as those described above for the positive electrode active material layer can be used.
- Nonaqueous electrolyte for example, known organic electrolytes, polymer solid electrolytes, gel electrolytes, inorganic solid electrolytes, and the like can be used. Among them, organic electrolytes are preferable.
- the organic electrolytic solution is configured by dissolving a solute (electrolyte) in an organic solvent.
- the type of the organic solvent is not particularly limited.
- a phosphoric acid ester compound or the like can be used.
- Typical examples are dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, propylene carbonate, ethylene carbonate, vinylene carbonate, vinyl ethylene carbonate, tetrahydrofuran, 2-methyltetrahydrofuran, 1,4-dioxane, 4-methyl-2- Pentanone, 1,2-dimethoxyethane, 1,2-diethoxyethane, ⁇ -butyrolactone, 1,3-dioxolane, 4-methyl-1,3-dioxolane, diethyl ether, sulfolane, methyl sulfolane, acetonitrile, propionitrile Benzonitrile, butyronitrile, valeronitrile, 1,2-dichloroethane, dimethylformamide, dimethyl sulfoxide, trimethyl phosphate, triethyl phosphate, etc.
- Et compounds hydrogen atoms may be partially substituted with a halogen atom. Moreover
- the above-mentioned organic solvent preferably contains a high dielectric constant solvent in order to dissociate the electrolytic salt.
- the high dielectric constant solvent means a compound having a relative dielectric constant of 20 or more at 25 ° C.
- the high dielectric constant solvents it is preferable that ethylene carbonate, propylene carbonate, and compounds in which hydrogen atoms thereof are substituted with other elements such as halogen or alkyl groups are contained in the electrolytic solution.
- the proportion of the high dielectric constant solvent in the electrolyte is preferably 20% by weight or more, more preferably 25% by weight or more, and most preferably 30% by weight or more. If the content of the high dielectric constant solvent is less than the above range, desired battery characteristics may not be obtained. *
- a gas such as CO 2 , N 2 O, CO, and SO 2 , vinylene carbonate, polysulfide S x 2 ⁇ , and the like that enable efficient charging and discharging of lithium ions on the negative electrode surface are excellent.
- vinylene carbonate is particularly preferable.
- additives such as lithium difluorophosphate that are effective in improving cycle life and output characteristics, and additives that are effective in suppressing high-temperature storage gases such as propane sultone and propene sultone May be added at an arbitrary ratio.
- the type of the electrolytic salt is not particularly limited, and any conventionally known solute can be used. Specific examples include LiClO 4 , LiAsF 6 , LiPF 6 , LiBF 4 , LiB (C 6 H 5 ) 4 , LiBOB, LiCl, LiBr, CH 3 SO 3 Li, CF 3 SO 3 Li, LiN (SO 2 CF 3 ) 2 , LiN (SO 2 C 2 F 5 ) 2 , LiC (SO 2 CF 3 ) 3 , LiN (SO 3 CF 3 ) 2 and the like. Any one of these electrolytic salts may be used alone, or two or more thereof may be used in any combination and ratio.
- the lithium salt of the electrolytic salt is usually contained in the electrolytic solution so as to be 0.5 mol / L or more and 1.5 mol / L or less. Even if the lithium salt concentration in the electrolytic solution is less than 0.5 mol / L or more than 1.5 mol / L, the electric conductivity may be lowered, and the battery characteristics may be adversely affected.
- the lower limit of this concentration is preferably 0.75 mol / L or more and the upper limit is 1.25 mol / L or less.
- a polymer solid electrolyte the kind thereof is not particularly limited, and any crystalline or amorphous inorganic substance known as a solid electrolyte can be used.
- the amorphous inorganic solid electrolyte include oxide glasses such as 4.9LiI-34.1Li 2 O-61B 2 O 5 and 33.3Li 2 O-66.7SiO 2 . Any one of these may be used alone, or two or more may be used in any combination and ratio.
- a separator is interposed between the positive electrode and the negative electrode in order to prevent a short circuit between the electrodes.
- the material and shape of the separator are not particularly limited, but those that are stable with respect to the organic electrolyte used, have excellent liquid retention properties, and can reliably prevent short-circuiting between electrodes are preferable.
- Preferable examples include microporous films, sheets, nonwoven fabrics and the like made of various polymer materials.
- polymer material examples include polyolefin polymers such as nylon, cellulose acetate, nitrocellulose, polysulfone, polyacrylonitrile, polyvinylidene fluoride, polypropylene, polyethylene, and polybutene.
- polyolefin polymers such as nylon, cellulose acetate, nitrocellulose, polysulfone, polyacrylonitrile, polyvinylidene fluoride, polypropylene, polyethylene, and polybutene.
- polyolefin polymers are preferable.
- polyethylene is preferred. Is particularly desirable.
- the lower limit of the molecular weight is preferably 500,000, more preferably 1,000,000, and most preferably 1.5 million.
- the upper limit of the molecular weight is preferably 5 million, more preferably 4 million, and most preferably 3 million. This is because if the molecular weight is too large, the fluidity becomes too low, and the pores of the separator may not close when heated.
- the lithium secondary battery of the present invention is manufactured by assembling the above-described positive electrode for a lithium secondary battery of the present invention, a negative electrode, an electrolyte, and a separator used as necessary into an appropriate shape. Furthermore, other components such as an outer case can be used as necessary.
- the shape of the lithium secondary battery of the present invention is not particularly limited, and can be appropriately selected from various commonly employed shapes according to the application. Examples of commonly used shapes include a cylinder type with a sheet electrode and separator spiral, an inside-out cylinder type with a combination of pellet electrode and separator, and a coin type with a stack of pellet electrode and separator. Can be mentioned. Also, the method for assembling the battery is not particularly limited, and can be appropriately selected from various commonly used methods according to the intended shape of the battery.
- the lithium secondary battery of the present invention is particularly effective in a battery that is designed so that the charging potential of the positive electrode in a fully charged state is 4.4 V (vs. Li / Li + ) or higher in the examples described later. Play. That is, when the lithium nickel manganese cobalt composite oxide powder for a lithium secondary battery positive electrode material of the present invention is used as a lithium secondary battery designed to be charged at a high charging potential, the effect of the present invention is achieved. Demonstrate effectively. However, the effect is sufficiently exerted even at a low potential of less than 4.4 V (vs. Li / Li + ).
- the lithium secondary battery of the present invention has been described above.
- the lithium secondary battery of the present invention is not limited to the above-described embodiment, and various modifications are possible as long as the gist thereof is not exceeded. Can be implemented. *
- XPS X-ray photoelectron spectroscopy
- the dark contrast part compared with a positive electrode active material is a compound which has a P (or Si) atom.
- the place observed with extremely bright contrast near the primary particle interface is a compound having W atoms.
- the contrast of the reflected electron image is mainly affected by the composition information and the surface shape information, but since the cross section of this time is extremely smooth, the surface shape information is almost negligible. In other words, the composition that controls the contrast is mostly the composition.
- SEM-EDX analysis was conducted using an OXFORD INSTRUMENTS INCA Energy at an electron gun acceleration voltage of 3 kV.
- the refractive index was set to 1.60, and the particle diameter standard was measured as the volume standard. The measurement was performed using a 0.1 wt% aqueous sodium hexametaphosphate solution as the dispersion medium.
- ⁇ Median diameter of pulverized particles in slurry> Using a known laser diffraction / scattering particle size distribution measuring apparatus, the refractive index was set to 1.24, and the particle diameter standard was measured as a volume standard. Moreover, 0.1 weight% sodium hexametaphosphate aqueous solution was used as a dispersion medium, and it measured after ultrasonic dispersion (output 30W, frequency 22.5kHz) for 5 minutes.
- this slurry (solid content 38% by weight, viscosity 1100 cP) was spray-dried using a two-fluid nozzle type spray dryer (Okawara Kako Co., Ltd .: LT-8 type).
- air was used as the dry gas
- the dry gas introduction amount G was 45 L / min
- the drying inlet temperature was 150 ° C.
- Particulate powder obtained by spray drying with a spray dryer is charged into an alumina crucible, fired in an air atmosphere at 650 ° C.
- this slurry (solid content 38% by weight, viscosity 1100 cP) was spray-dried using a two-fluid nozzle type spray dryer (Okawara Kako Co., Ltd .: LT-8 type).
- air was used as the dry gas
- the dry gas introduction amount G was 45 L / min
- the drying inlet temperature was 150 ° C.
- Particulate powder obtained by spray drying with a spray dryer is placed in an alumina crucible, fired at 650 ° C.
- this slurry (solid content 38% by weight, viscosity 1100 cP) was spray-dried using a two-fluid nozzle type spray dryer (Okawara Kako Co., Ltd .: LT-8 type).
- air was used as the dry gas
- the dry gas introduction amount G was 45 L / min
- the drying inlet temperature was 150 ° C.
- Particulate powder obtained by spray drying with a spray dryer is placed in an alumina crucible, fired at 650 ° C.
- this slurry (solid content 38% by weight, viscosity 1100 cP) was spray-dried using a two-fluid nozzle type spray dryer (Okawara Kako Co., Ltd .: LT-8 type).
- air was used as the dry gas
- the dry gas introduction amount G was 45 L / min
- the drying inlet temperature was 150 ° C.
- Particulate powder obtained by spray drying with a spray dryer is charged into an alumina crucible, fired in an air atmosphere at 650 ° C.
- this slurry (solid content 38% by weight, viscosity 1100 cP) was spray-dried using a two-fluid nozzle type spray dryer (Okawara Kako Co., Ltd .: LT-8 type).
- air was used as the dry gas
- the dry gas introduction amount G was 45 L / min
- the drying inlet temperature was 150 ° C.
- Particulate powder obtained by spray drying with a spray dryer is placed in an alumina crucible, fired at 650 ° C.
- this slurry (solid content 38% by weight, viscosity 1100 cP) was spray-dried using a two-fluid nozzle type spray dryer (Okawara Kako Co., Ltd .: LT-8 type).
- air was used as the dry gas
- the dry gas introduction amount G was 45 L / min
- the drying inlet temperature was 150 ° C.
- Particulate powder obtained by spray drying with a spray dryer is placed in an alumina crucible, fired at 650 ° C.
- the average primary particle diameter, median diameter, 90% cumulative diameter (D 90 ), bulk density, and BET specific surface area as the acceptance criteria of the examples. It was set as a judgment (circle) that the powder property value of each example was comparable or improved with respect to the powder property value of the corresponding comparative example.
- Table 1 shows that the specific surface area of the lithium nickel manganese cobalt composite oxide powder produced in the example is larger than that of the comparative example while having the same bulk density.
- FIGS. 7 shows SEM-EDX images (photos) of the manufactured lithium nickel manganese cobalt composite oxide powder.
- lithium transition metal-based compound powders produced in the above Examples and Comparative Examples as positive electrode materials (positive electrode active materials)
- lithium secondary batteries were produced and evaluated by the following methods.
- EC ethylene carbonate
- EMC ethyl methyl carbonate
- 3: 3: 4 volume ratio
- the obtained coin-type cell was subjected to a constant current constant voltage charge of 0.2 mA / cm 2 at an upper limit voltage of 4.2 V and a constant current discharge test of 0.2 mA / cm 2 at a lower limit voltage of 3.0 V for the first cycle.
- a constant current constant voltage charge of 0.5 mA / cm 2 at an upper limit voltage of 4.2 V and a constant current discharge test of 0.2 mA / cm 2 at a lower limit voltage of 3.0 V were conducted.
- constant current charge of 0.5 mA / cm 2 was constant current discharge test of 11 mA / cm 2.
- the ratio of the discharge capacity Qh (100) at the third cycle was calculated as the capacity density by the following formula, and the battery characteristics were compared with this value.
- Capacity density [mAh / cm 2 ] discharge capacity at the third cycle (mAh / g) ⁇ bulk density (g / cm 2 )
- Table 2 shows the initial discharge capacity at the first cycle, the high-rate discharge capacity at the third cycle, and the capacity density of the batteries using the mixed powders or non-mixed powders of Examples and Comparative Examples, respectively.
- the initial charge capacity per unit weight of the positive electrode active material is Qs (C) [mAh / g] and the initial discharge capacity is Qs (D) [mAh / g].
- This slurry was applied to one side of a 20 ⁇ m thick copper foil, dried to evaporate the solvent, punched to 12 mm ⁇ , and pressed at 0.5 ton / cm 2 (49 MPa) to form a negative electrode. At this time, the amount of the negative electrode active material on the electrode was adjusted to about 5 to 12 mg.
- the initial occlusion capacity per unit weight of the negative electrode active material at a lower limit of 0 V was defined as Qf [mAh / g].
- the negative electrode can was placed and sealed, and a coin-type lithium secondary battery was produced.
- the balance between the weight of the positive electrode active material and the weight of the negative electrode active material was set so as to satisfy the following expression.
- Positive electrode active material weight [g] / Negative electrode active material weight [g] (Qf [mAh / g] /1.2) Qs (C) [mAh / g]
- the hourly rate current value of the battery that is, 1C was set as shown in the following equation, and the following tests were performed.
- 1C [mA] Qs (D) ⁇ positive electrode active material weight [g] / hour [h]
- a constant current 0.2C charge / discharge cycle and a constant current 1C charge / discharge cycle were performed at room temperature.
- the upper limit of charging was 4.1 V
- the lower limit voltage was 3.0 V.
- a constant current 0.2 C charge / discharge cycle was conducted at a high temperature of 60 ° C., and then a constant current 1 C charge / discharge cycle 100 was tested.
- the upper limit of charging was 4.1 V, and the lower limit voltage was 3.0 V.
- the ratio of the discharge capacity Qh (100) at the 100th cycle of 1C charge / discharge at 60 ° C. is calculated as the high temperature cycle capacity maintenance rate (cycle maintenance rate) P by the following formula, and the high temperature characteristics of the battery with this value. Compared.
- the hourly rate current value of the battery that is, 1C was set as shown in the following equation, and the following tests were performed.
- a coin cell adjusted to a charge depth of 40% by 1/3 C constant current charge / discharge was held in a low temperature atmosphere of ⁇ 30 ° C. for 1 hour or more, and then a constant current of 0.5 C [mA ],
- V [mV] the voltage after 10 seconds of discharge
- V 0 [mV] V ⁇ V 0
- the resistance value R [ ⁇ ] from the following equation: Was calculated.
- Resistance increase rate [%] resistance R1 after 100 cycles / resistance R2 ⁇ 100 before cycles
- the battery characteristic value of each example corresponds as a pass criterion of the example in the rate test, capacity density and P (cycle capacity maintenance rate). It was set as a judgment (circle) that it was the same or improved with respect to the battery characteristic value of the comparative example.
- the lithium nickel manganese cobalt composite oxide powder of the present invention has a large specific surface area of the active material and a high bulk density. Thereby, it can be seen that the battery capacity (capacity density) per electrode area is large and the capacity can be increased.
- the application of the lithium secondary battery using the lithium transition metal-based composite oxide powder of the present invention is not particularly limited, and can be used for various known applications. Specific examples include notebook computers, pen input computers, mobile computers, electronic book players, mobile phones, mobile faxes, mobile copy, mobile printers, headphone stereos, video movies, LCD TVs, handy cleaners, portable CDs, minidiscs, and transceivers. , Electronic notebook, calculator, memory card, portable tape recorder, radio, backup power supply, motor, lighting equipment, toy, game machine, clock, strobe, camera, pacemaker, electric tool, automotive power source, track vehicle power source, artificial Examples include a power source for satellites.
Abstract
Description
さらに、低コスト、安全性、寿命(特に高温下)にも優れた、性能バランスの良い材料が求められている。
(1)
リチウムイオンの挿入・脱離が可能な機能を有するリチウム遷移金属系化合物を含む粉体であって、該粉体の粒子の内部に、周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素、並びに、第5周期及び第6周期の第5~7族元素から選ばれる少なくとも1種の元素に由来するSEM-EDX法によるピークを有する化合物を有するリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
(2)
リチウム遷移金属系化合物が、二種以上の組成を持つ一次粒子から構成される二次粒子からなる粉体であって、二次粒子の少なくとも内部に、周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素、並びに、第5周期及び第6周期の第5~7族元素から選ばれる少なくとも1種の元素に由来するSEM-EDX法によるピークを有する化合物の一次粒子を有する上記(1)に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
(3)
リチウムイオンの挿入・脱離が可能な機能を有するリチウム遷移金属系化合物を含み、該リチウム遷移金属系化合物の原料となるリチウム源及び遷移金属源と、構造式中に周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素を有する化合物とを、粉砕及び混合した後、焼成することにより得られる、リチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
(4)
リチウムイオンの挿入・脱離が可能な機能を有するリチウム遷移金属系化合物を含み、該リチウム遷移金属系化合物の原料に、周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素を有する化合物並びに第5周期及び第6周期の第5~7族元素から選ばれる少なくとも1種の元素を有する化合物を添加して焼成することにより得られる、リチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
(5)
前記周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素が、S、Se、Te及びPoからなる群より選ばれる少なくとも一種の元素である上記(1)ないし(4)のいずれか1に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
(6)
前記周期表第5周期及び第6周期の第5~7族元素から選ばれる少なくとも1種の元素が、Mo、W、Nb、Ta及びReからなる群より選ばれる少なくとも一種の元素である上記(1)ないし(5)のいずれか1に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
(7)
前記リチウム遷移金属系化合物が、細孔分布曲線において、細孔半径80nm以上800nm未満にピークを有する上記(1)ないし(6)のいずれか1に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
(8)
二次粒子の表面部分のLi、S、Se、Te、Po、Mo、W、Nb、Ta及びRe元素以外の金属元素の合計に対するS、Se、Te及びPo元素の合計のモル比が、二次粒子全体の該モル比の500倍以下である上記(2)ないし(7)のいずれか1に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
(9)
二次粒子の表面部分のLi、S、Se、Te、Po、Mo、W、Nb、Ta及びRe元素以外の金属元素の合計に対するMo、W、Nb、Ta及びRe元素の合計のモル比が、二次粒子全体の該モル比の1.05倍以上である上記(2)ないし(8)のいずれか1に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
(10)
BET比表面積が0.5m2/g以上、3m2/g以下である上記(1)ないし(9)のいずれか1に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
(11)
嵩密度が1.2g/cm3以上、2.8g/cm3以下である上記(1)ないし(10)のいずれか1に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
(12)
前記リチウム遷移金属系化合物が、層状構造を有するリチウムニッケルマンガンコバルト系複合酸化物又はスピネル構造を有するリチウムマンガン系複合酸化物である、上記(1)ないし(11)のいずれか1に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
(13)
組成が、下記組成式(A)又は(B)で示される上記(12)に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
Li1+xMO2 ・・・(A)
(ただし、上記式(A)中、xは0以上、0.5以下、Mは、Li、Ni及びMn、又は、Li、Ni、Mn及びCoから構成される元素であり、Mn/Niモル比は0.1以上、5以下、Co/(Mn+Ni+Co)モル比は0以上、0.35以下、M中のLiモル比は0.001以上、0.2以下である。)
Li[LiaM’bMn2-b-a]O4+δ・・・(B)
(ただし、上記式(B)中、a、b及びδは、0≦a≦0.3、0.4≦b≦0.6、-0.5≦δ≦0.5を満たし、M’は、Ni、Cr、Fe、Co及びCuから選ばれる遷移金属のうちの少なくとも1種を表す。)
(14)
酸素含有ガス雰囲気下において、焼成温度1000℃以上で焼成して得られる上記(1)ないし(13)のいずれか1に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
(15)
さらに、Mo、W、Nb、Ta及びReから選ばれる少なくとも1種の元素を含有する化合物と、B及びBiから選ばれる少なくとも1種の元素を含有する化合物とを併用添加した後、焼成して得られる上記(1)ないし(14)のいずれか1に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
(16)
リチウム化合物と、Mn、Co、及びNiから選ばれる少なくとも1種の遷移金属化合物と、周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素を含有する化合物とを、液体媒体中で粉砕し、これらを均一に分散させたスラリーを調製する工程と、該スラリーを噴霧乾燥する噴霧乾燥工程と、得られた噴霧乾燥体を焼成する焼成工程とを含むリチウム二次電池正極材料用リチウム遷移金属系化合物粉体の製造方法。
(17)
スラリー調製工程において、リチウム化合物と、前記遷移金属化合物と、前記周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素を含有する化合物とを、液体媒体中で、下記条件に従って測定するメジアン径が0.6μm以下になるまで粉砕し、
噴霧乾燥工程において、噴霧乾燥時のスラリー粘度をV(cP)、スラリー供給量をS(L/min)、ガス供給量をG(L/min)とした際、50cP≦V≦7000cP、500≦G/S≦10000となる条件で噴霧乾燥を行う上記(16)に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体の製造方法。
(メジアン径測定条件は下記に従う。
i)出力30W、周波数22.5kHzの超音波分散を5分間行った後、
ii)レーザー回折/散乱式粒度分布測定装置によって、屈折率を1.24に設定し、粒子径基準を体積基準として、メジアン径を測定する)
(18)
前記遷移金属化合物として少なくともニッケル化合物、マンガン化合物及びコバルト化合物を含み、前記焼成工程において、前記噴霧乾燥体を、酸素含有ガス雰囲気下、1000℃以上で焼成する上記(16)又は(17)に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体の製造方法。
(19)
リチウム化合物が炭酸リチウムである上記(16)ないし(18)のいずれか1に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体の製造方法。
(20)
上記(1)ないし(15)のいずれか1に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体及び結着剤を含有する正極活物質層と集電体とを有するリチウム二次電池用正極。
(21)
リチウムを吸蔵・放出可能な負極、リチウム塩を含有する非水電解質、及びリチウムを吸蔵・放出可能な正極を備えたリチウム二次電池であって、正極が上記(20)に記載のリチウム二次電池用正極であるリチウム二次電池。
また、“重量%”、“重量ppm”及び“重量部”は、それぞれ“質量%”、“質量ppm”及び“質量部”と同義である。
本発明の正極活物質は、以下のとおりである。
(1)リチウムイオンの挿入・脱離が可能な機能を有するリチウム遷移金属系化合物を含む粉体であって、該粉体の粒子の内部に、周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素(以下「本発明の添加元素1」とも称す。)、並びに、周期表第5周期及び第6周期の第5~7族元素から選ばれる少なくとも1種の元素(以下「本発明の添加元素2」とも称す。)に由来するSEM-EDX法によるピークを有する化合物を含むリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
(2)リチウムイオンの挿入・脱離が可能な機能を有するリチウム遷移金属系化合物を含み、該リチウム遷移金属系化合物の原料となるリチウム源及び遷移金属源と、構造式中に周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素(本発明の添加元素1)とを、粉砕及び混合した後、焼成することにより得られるリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
(3)リチウムイオンの挿入・脱離が可能な機能を有するリチウム遷移金属系化合物を含み、該リチウム遷移金属系化合物の原料に、周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素(本発明の添加元素)を有する化合物並びに第5周期及び第6周期の第5~7族元素から選ばれる少なくとも1種の元素(本発明の添加元素2)を有する化合物を添加して焼成することにより得られるリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
本発明においてリチウム遷移金属系化合物とは、Liイオンを脱離、挿入することが可能な構造を有する化合物であり、例えば、硫化物やリン酸塩化合物、リチウム遷移金属複合酸化物などが挙げられる。硫化物としては、TiS2やMoS2などの二次元層状構造をもつ化合物や、一般式MexMo6S8(MeはPb、Ag、Cuをはじめとする各種遷移金属)で表される強固な三次元骨格構造を有するシュブレル化合物などが挙げられる。リン酸塩化合物としては、オリビン構造に属するものが挙げられ、一般的にはLiMePO4(Meは少なくとも1種の遷移金属)で表され、具体的にはLiFePO4、LiCoPO4、LiNiPO4、LiMnPO4などが挙げられる。リチウム遷移金属複合酸化物としては、三次元的拡散が可能なスピネル構造や、リチウムイオンの二次元的拡散を可能にする層状構造に属するものが挙げられる。スピネル構造を有するものは、一般的にLiMe2O4(Meは少なくとも1種の遷移金属)と表され、具体的にはLiMn2O4、LiCoMnO4、LiNi0.5Mn1.5O4、LiCoVO4などが挙げられる。
層状構造を有するものは、一般的にLiMeO2(Meは少なくとも1種の遷移金属)と表され、具体的にはLiCoO2、LiNiO2、LiNi1-xCoxO2、LiNi1-x-yCoxMnyO2、LiNi0.5Mn0.5O2、Li1.2Cr0.4Mn0.4O2、Li1.2Cr0.4Ti0.4O2、LiMnO2などが挙げられる。
本発明のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体(以下「本発明のリチウム遷移金属系化合物粉体」とも称する。)は、リチウムイオンの挿入・脱離が可能な機能を有するリチウム遷移金属系化合物を含む粉体であって、該粉体の粒子の内部に、周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素(本発明の添加元素1)、並びに、第5周期及び第6周期の第5~7族元素から選ばれる少なくとも1種の元素(本発明の添加元素2)に由来するSEM-EDX法によるピークを有する化合物を有することを特徴としている。また、リチウム遷移金属系化合物が、二種以上の組成を持つ一次粒子から構成される二次粒子からなる粉体であって、二次粒子の少なくとも内部に、第3周期以降の第16族元素から選ばれる少なくとも一種の元素(本発明の添加元素1)、並びに、第5周期及び第6周期の第5~7族元素から選ばれる少なくとも1種の元素(本発明の添加元素2)に由来するSEM-EDX法によるピークを有する化合物の一次粒子を有することが好ましい。
本発明のリチウム遷移金属系化合物粉体は、その一次粒子の表面部分に、本発明の添加剤1由来の元素、即ち、周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素(本発明の添加元素1)が濃化して存在していることが、さらに好ましい。具体的には、一次粒子の表面部分の、Liと添加元素以外の金属元素(即ち、Liと添加元素以外の金属元素)の合計に対する添加元素の合計のモル比が、通常、粒子全体の該モル比の1倍以上であることが好ましく、この比率の下限は1.05倍以上であることがさらに好ましく、1.1倍以上であることがより好ましく、2倍以上であることが特に好ましい。上限は通常、特に制限されないが、500倍以下であることが好ましく、300倍以下であることがより好ましく、100倍以下であることが特に好ましく、50倍以下であることが最も好ましい。この比率が小さすぎると粉体物性の改善効果が小さくなる場合があり、反対に大きすぎると電池性能の悪化を招く場合がある。
本発明のリチウム遷移金属系化合物粉体は、リチウム遷移金属系化合物を主成分として含む。そして、本発明のリチウム遷移金属系化合物粉体は、該主成分原料となるリチウム源及び遷移金属源と、構造式中に第3周期以降の第16族元素から選ばれる少なくとも一種の元素(本発明の添加元素1)を含有する化合物(以下「本発明の添加剤1」とも称す。)とを、粉砕及び混合した後、焼成することにより得られることを特徴としている。従って、構造式中にS原子を含有する化合物が、リチウム遷移金属系化合物に含有されている。
例えば、本発明に好適な後述の組成式(A)又は(B)で規定する組成領域のリチウムニッケルマンガンコバルト系複合酸化物粉体を、主成分原料を同時に液体媒体中で粉砕し、これらを均一に分散させたスラリーを噴霧乾燥して焼成することを含む製造方法によって製造する場合、高温で焼成結果、高密度化及び比表面積の減縮をもたらし、高電流密度での放電容量が低下する。つまり、双方を両立して改善することが極めて困難な状況となるが、例えば、「構造式中に本発明の添加元素1」を含有する化合物(「本発明の添加剤1」)」を添加して焼成することにより、このトレードオフの関係を克服することが可能となる。
Se元素を有する化合物としては、H2SeO4、SeO2などの酸化物、SeF4、SeCl2などのハロゲン化合物、オキシ塩化セレンなどが挙げられ、これらの中でも、酸化物であることがCO2、F2などのガス発生量が少ないため好ましく、SeO2が特に好ましい。
Te元素を有する化合物としては、TeO、TeO2、H2TeO3などの酸化物、TeF6、TeCl4、TeBr4などのハロゲン化物などが挙げられ、これらの中でも、酸化物であることがCO2、F2などのガス発生量が少ないため好ましく、TeO2が特に好ましい。
なお、これらの添加剤1は1種を単独で使用しても良く、2種以上を併用しても良い。
本発明では、上記の構造式中に周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素(本発明の添加元素1)を含有する化合物(本発明の添加剤1)に加えて、更なる添加元素として、周期表第5周期又は第6周期の第5~7族元素から選ばれる少なくとも1種の元素(本発明の添加元素2)を含有する化合物(本発明の添加剤2)を用いる。これらの本発明の添加元素2の中でも、効果が大きい点から、本発明の添加元素2が、Mo、W、Nb、Ta及びReからなる群より選ばれる少なくとも一種の元素であることが好ましく、Mo又はWであることがさらに好ましく、Wであることが最も好ましい。
添加剤2の例示化合物としては、Mo元素を有する化合物としては、MoO、MoO2、MoO3、MoOx、Mo2O3、Mo2O5、Li2MoO4が挙げられる。W元素を有する化合物としては、WO、WO2、WO3、H2WO4、WOx、W2O3、W2O5、W18O49、W20O58、W24O70,W25O73、W40O118、Li2WO4、メタタングステン酸アンモニウム、パラタングステン酸アンモニウムが挙げられる。Nb元素を有する化合物としては、NbO、NbO2、Nb2O3、Nb2O5、Nb2O5・nH2O、LiNbO3が挙げられる。Ta元素を有する化合物としては、Ta2O、Ta2O5、LiTaO3が挙げられる。Re元素を有する化合物としては、ReO2、ReO3、Re2O3、Re2O7などが挙げられる。これらの中でも、工業原料として比較的入手し易い、又はリチウムを包含するといった点から、好ましくはMoO3、Li2MoO4、WO3、Li2WO4が挙げられ、特に好ましくはWO3が挙げられる。これらの添加剤2は1種を単独で用いても良く、2種以上を混合して用いても良い。
本発明のリチウム遷移金属系化合物粉体のメジアン径は通常1μm以上、好ましくは2.5μm以上、より好ましくは3μm以上、更に好ましくは3.5μm以上、最も好ましくは4μm以上で、通常50μm以下、好ましくは25μm以下、より好ましくは20μm以下、更に好ましくは18μm以下、最も好ましくは16μm以下である。メジアン径がこの下限を下回ると、正極活物質層形成時の塗布性に問題を生ずる可能性があり、上限を超えると電池性能の低下を来たす可能性がある。
本発明のリチウムリチウム遷移金属系化合物粉体の平均径(平均一次粒子径)としては、特に限定されないが、下限としては、好ましくは0.1μm以上、より好ましくは0.2μm以上、最も好ましくは0.3μm以上、また、上限としては、好ましくは3μm以下、より好ましくは2μm以下、さらに好ましくは1.5μm以下、最も好ましくは1.2μm以下である。平均一次粒子径が、上記上限を超えると、粉体充填性に悪影響を及ぼしたり、比表面積が低下したりするために、レート特性や出力特性等の電池性能が低下する可能性が高くなる可能性がある。上記下限を下回ると結晶が未発達であるために充放電の可逆性が劣る等の問題を生ずる可能性がある。
本発明のリチウムリチウム遷移金属系化合物粉体はまた、BET比表面積が、通常0.5m2/g以上、好ましくは0.6m2/g以上、更に好ましくは0.7m2/g以上、最も好ましくは0.8m2/g以上で、通常3m2/g以下、好ましくは2.8m2/g以下、更に好ましくは2.5m2/g以下、最も好ましくは2.3m2/g以下である。BET比表面積がこの範囲よりも小さいと電池性能が低下しやすく、大きいと嵩密度が上がりにくくなり、正極活物質形成時の塗布性に問題が発生しやすくなる可能性がある。
本発明のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体は、好ましくは水銀圧入法による測定において、特定の条件を満たす。
本発明のリチウム遷移金属系化合物粉体の評価で採用する水銀圧入法について以下に説明する。
水銀圧入法は、多孔質粒子等の試料について、圧力を加えながらその細孔に水銀を浸入させ、圧力と圧入された水銀量との関係から、比表面積や細孔径分布などの情報を得る手法である。
水銀は表面張力が高く、そのままでは試料表面の細孔には水銀は浸入しないが、水銀に圧力をかけ、徐々に昇圧していくと、径の大きい細孔から順に径の小さい孔へと、徐々に細孔の中に水銀が浸入していく。圧力を連続的に増加させながら水銀液面の変化(つまり細孔への水銀圧入量)を検出していけば、水銀に加えた圧力と水銀圧入量との関係を表す水銀圧入曲線が得られる。
Pr=-2δ(cosθ) …(2)
水銀の場合、表面張力δ=480dyn/cm程度、接触角θ=140°程度の値が一般的に良く用いられる。これらの値を用いた場合、圧力P下で水銀が圧入される細孔の半径は以下の数式(3)で表される。
水銀圧入法による測定は、水銀ポロシメータ等の装置を用いて行うことができる。水銀ポロシメータの具体例としては、Micromeritics社製オートポア、Quantachrome社製ポアマスター等が挙げられる。
なお、本明細書において「細孔分布曲線」とは、細孔の半径を横軸に、その半径以上の半径を有する細孔の単位重量(通常は1g)当たりの細孔体積の合計を、細孔半径の対数で微分した値を縦軸にプロットしたものであり、通常はプロットした点を結んだグラフとして表す。特に本発明のリチウム遷移金属系化合物粉体を水銀圧入法により測定して得られた細孔分布曲線を、以下の記載では適宜「本発明にかかる細孔分布曲線」という。
また、本明細書において「ピークトップ」とは、細孔分布曲線が有する各ピークにおいて縦軸の座標値が最も大きい値をとる点をいう。
本発明に係る細孔分布曲線が有するピーク1は、そのピークトップが、細孔半径が通常80nm以上、より好ましくは90nm以上、最も好ましくは100nm以上、また、通常800nm以下、好ましくは750nm以下、より好ましくは700nm以下、更に好ましくは650nm以下、最も好ましくは600nm以下の範囲に存在する。この範囲の上限を超えると、本発明のリチウム遷移金属系化合物粉体を正極材料として電池を作成した場合に、粒子内部の空隙が多すぎる状態を表しており、電極を作成した際に電極密度が低下してしまい放電容量などの特性が低下する可能性がある。一方、この範囲の下限を下回ると、本発明のリチウム遷移金属系化合物粉体を用いて正極を作製した場合に、粒子内部の空隙がない状態を表しており、出力特性が低下する可能性がある。
本発明に係る細孔分布曲線は、上述のピーク1に加えて、複数のピークを有していてもよく、特には800nm以上、4000nm以下の細孔半径の範囲内にピークトップが存在するピーク2を有することが好ましい。
本発明のリチウム遷移金属系化合物粉体の嵩密度は通常1.2g/cm3以上、好ましくは1.3g/cm3以上、より好ましくは1.4g/cm3以上、最も好ましくは1.5g/cm3以上で、通常2.8g/cm3以下、好ましくは2.7g/cm3以下、より好ましくは2.6g/cm3以下、最も好ましくは2.5g/cm3以下である。嵩密度がこの上限を上回ることは、粉体充填性や電極密度向上にとって好ましい一方、比表面積が低くなり過ぎる可能性があり、電池性能が低下する可能性がある。嵩密度がこの下限を下回ると粉体充填性や電極調製に悪影響を及ぼす可能性がある。
本発明のリチウム遷移金属系化合物粉体は、少なくとも層状構造を有するリチウムニッケルマンガンコバルト系複合酸化物及び/又はスピネル構造を有するリチウムマンガン系複合酸化物を主成分としたものが好ましい。これらの中でも、結晶格子の膨張・収縮が大きく、本発明の効果が顕著であるため、層状構造を有するリチウムニッケルマンガンコバルト系複合酸化物を主成分としたものがさらに好ましい。なお、本発明においては、リチウムニッケルマンガンコバルト系複合酸化物のうち、コバルトを含まないリチウムニッケルマンガン系複合酸化物も「リチウムニッケルマンガンコバルト系複合酸化物」との文言に含むものとする。
ただし、層状LiMeO2とは、層状R(-3)m構造に限るものではない。これ以外にもいわゆる層状Mnと呼ばれるLiMnO2は斜方晶系で空間群Pm2mの層状化合物であり、また、いわゆる213相と呼ばれるLi2MnO3は、Li[Li1/3Mn2/3]O2とも表記でき、単斜晶系の空間群C2/m構造であるが、やはりLi層と[Li1/3Mn2/3]層及び酸素層が積層した層状化合物である。
ただし、スピネル型LiMeO4とは、スピネル型Fd(-3)m構造に限るものではない。これ以外にも異なる空間郡(P4332)に属するスピネル型LiMeO4も存在する。
また、本発明のリチウム含有遷移金属化合物粉体は、下記組成式(A)又は(B)で示されるリチウム遷移金属系化合物粉体であることが好ましい。
さらに、層状化合物においては、スピネル型化合物と比較して、相対的にMnの溶出量が少なく、サイクル特性におよぼすMnの影響が少ないため、本発明の効果がより明確な差となって現れる。従って、本発明は下記組成式(A)で示されるリチウム遷移金属系化合物粉体であることが、さらに好ましい。
Li1+xMO2 …(A)
上記式(A)中、xは通常0以上、好ましくは0.01以上、更に好ましくは0.02以上、最も好ましくは0.03以上、通常0.5以下、好ましくは0.4以下、更に好ましくは0.3以下、最も好ましくは0.2以下である。
Mは、Li、Ni及びMn、又は、Li、Ni、Mn及びCoから構成される元素である。
また、Mn/Niモル比は通常0.1以上、好ましくは0.3以上、より好ましくは0.5以上、更に好ましくは0.6以上、より一層好ましくは0.7以上、更に好ましくは0.8以上、最も好ましくは0.9以上、通常12以下、好ましくは10以下、より好ましくは9以下、更に好ましくは8以下、最も好ましくは7以下である。
Co/(Mn+Ni+Co)モル比は通常0以上、好ましくは0.01以上、より好ましくは0.02以上、更に好ましくは0.03以上、最も好ましくは0.05以上、通常0.35以下、好ましくは0.20以下、より好ましくは0.15以下、更に好ましくは0.10以下、最も好ましくは0.099以下である。
M中のLiモル比は通常0.001以上、好ましくは0.01以上、より好ましくは0.02以上、さらに好ましくは0.03以上、最も好ましくは0.05以上、通常0.2以下、好ましくは0.19以下、より好ましくは0.18以下、さらに好ましくは0.17以下、最も好ましくは0.15以下である。
ただし、M’は、Ni、Cr、Fe、Co及びCuから選ばれる遷移金属のうちの少なくとも1種であり、これらの中でも、高電位における充放電容量の点から、最も好ましくはNiである。
aの値は通常0以上、好ましくは0.01以上、より好ましくは0.02以上、さらに好ましくは0.03以上、最も好ましくは0.04以上、通常0.3以下、好ましくは0.2以下、より好ましくは0.15以下、更に好ましくは0.1以下、最も好ましくは0.075以下である。aの値がこの範囲であれば、リチウム遷移金属系化合物における単位重量当たりのエネルギー密度を大きく損なわず、かつ、良好な負荷特性が得られるため、好ましい。
bの値は通常0.4以上、好ましくは0.425以上、より好ましくは0.45以上、さらに好ましくは0.475以上、最も好ましくは0.49以上、通常0.6以下、好ましくは0.575以下、より好ましくは0.55以下、更に好ましくは0.525以下、最も好ましくは0.51以下である。bの値がこの範囲であれば、リチウム遷移金属系化合物における単位重量当たりのエネルギー密度が高く、好ましい。
さらに、δの値は通常±0.5の範囲、好ましくは±0.4の範囲、より好ましくは±0.2の範囲、さらに好ましくは±0.1の範囲、特に好ましくは±0.05の範囲である。δの値がこの範囲であれば、結晶構造としての安定性が高く、このリチウム遷移金属系化合物を用いて作製した電極を有する電池のサイクル特性や高温保存が良好であるため、好ましい。
上記リチウム遷移金属系化合物の組成式のa,bを求めるには、各遷移金属とリチウムを誘導結合プラズマ発光分光分析装置(ICP-AES)で分析して、Li/Ni/Mnの比を求める事で計算される。
構造的視点では、aに係るリチウムは、同じ遷移金属サイトに置換されて入っていると考えられる。ここで、aに係るリチウムによって、電荷中性の原理によりMとマンガンの平均価数が3.5価より大きくなる。
本発明のリチウム遷移金属系化合物粉体が上述の効果をもたらす理由としては次のように考えられる。
活物質の焼成時に、活物質の焼成温度より低い温度の溶解する化合物が系中に存在すれば、焼成時の一次粒子の移動が簡易になり嵩密度が上がると推察される。但し、一次粒子が大きくなるとSSAが下がるため、一次粒子の成長を起こさないで焼成することが重要である。本発明の添加剤1は、焼成時一次粒子の成長を起こさずに一次粒子を移動し易くし、嵩密度を上げる効果があると推察される。
即ち、本発明のリチウム遷移金属系化合物粉体は、結晶二次粒子が球状の形骸を維持しており、嵩密度を落とせずに比表面積が大きいために、これを用いて電池を作製した場合に正極活物質表面と電解液との接触面積を増加させることが可能となることに加え、負荷特性の向上をもたらすような表面状態となり、正極活物質として優れた特性バランスと粉体取り扱い性を達成できたものと推定される。
さらに、本願発明では、本発明の添加元素1および添加元素2を有する化合物が活物質に存在することで、Liイオン伝導度又は電子伝導度が向上し、電池の負荷特性が向上すると推察できる。
本発明のリチウム遷移金属系化合物粉体を製造する方法は、特定の製法に限定されるものではないが、リチウム化合物と、Mn、Co及びNiから選ばれる少なくとも1種の遷移金属化合物と、本発明の添加剤とを、液体媒体中で粉砕し、これらを均一に分散させたスラリーを得るスラリー調製工程と、得られたスラリーを噴霧乾燥する噴霧乾燥工程と、得られた噴霧乾燥体を焼成する焼成工程を含む製造方法により、好適に製造される。
以下に、本発明の好適態様であるリチウムニッケルマンガンコバルト系複合酸化物粉体の製造方法を例にあげて、本発明のリチウム遷移金属系化合物粉体の製造方法について詳細に説明する。
本発明の方法により、リチウム遷移金属系化合物粉体を製造するに当たり、スラリーの調製に用いる原料化合物のうち、リチウム化合物としては、Li2CO3、LiNO3、LiNO2、LiOH、LiOH・H2O、LiH、LiF、LiCl、LiBr、LiI、CH3OOLi、Li2O、Li2SO4、ジカルボン酸Li、クエン酸Li、脂肪酸Li、アルキルリチウム等が挙げられる。これらリチウム化合物の中で好ましいのは、焼成処理の際にSOX、NOX等の有害物質を発生させない点で、窒素原子や硫黄原子、ハロゲン原子を含有しないリチウム化合物であり、また、焼成時に分解ガスを発生する等して、噴霧乾燥粉体の二次粒子内に分解ガスを発生するなどして空隙を形成しやすい化合物であり、これらの点を勘案すると、Li2CO3、LiOH、LiOH・H2Oが好ましく、特にLi2CO3が好ましい。これらのリチウム化合物は1種を単独で使用しても良く、2種以上を併用しても良い。
原料の混合方法は特に限定されるものではなく、湿式でも乾式でも良い。例えば、ボールミル、振動ミル、ビーズミル等の装置を使用する方法が挙げられる。原料化合物を水、アルコール等の液体媒体中で混合する湿式混合は、より均一な混合が可能であり、かつ焼成工程において混合物の反応性を高めることができるので好ましい。
なお、原料の混合段階においてはそれと並行して原料の粉砕が為されていることが好ましい。粉砕の程度としては、粉砕後の原料粒子の粒径が指標となるが、平均粒子径(メジアン径)として通常0.6μm以下、好ましくは0.55μm以下、さらに好ましくは0.52μm以下、最も好ましくは0.5μm以下とする。粉砕後の原料粒子の平均粒子径が大きすぎると、焼成工程における反応性が低下するのに加え、組成が均一化し難くなる。
ただし、必要以上に小粒子化することは、粉砕のコストアップに繋がるので、平均粒子径が通常0.01μm以上、好ましくは0.02μm以上、さらに好ましくは0.05μm以上となるように粉砕すれば良い。このような粉砕程度を実現するための手段としては特に限定されるものではないが、湿式粉砕法が好ましい。具体的にはダイノーミル等を挙げることができる。
湿式混合後は、次いで通常乾燥工程に供される。乾燥方法は特に限定されないが、生成する粒子状物の均一性や粉体流動性、粉体ハンドリング性能、乾燥粒子を効率よく製造できる等の観点から噴霧乾燥が好ましい。
本発明のリチウムニッケルマンガンコバルト系複合酸化物粉体等のリチウム遷移金属系化合物粉体の製造方法においては、原料化合物と本発明の添加剤とを湿式粉砕して得られたスラリーを噴霧乾燥することにより、一次粒子が凝集して二次粒子を形成してなる粉体を得る。一次粒子が凝集して二次粒子を形成してなる噴霧乾燥粉体は、本発明品の噴霧乾燥粉体の形状的特徴である。形状の確認方法としては、例えば、SEM観察、断面SEM観察が挙げられる。
このようにして得られた焼成前駆体は、次いで焼成処理される。
ここで、本発明において「焼成前駆体」とは、噴霧乾燥粉体を処理して得られる焼成前のリチウムニッケルマンガンコバルト系複合酸化物等のリチウム遷移金属系化合物の前駆体を意味する。例えば、前述の焼成時に分解ガスを発生又は昇華して、二次粒子内に空隙を形成させる化合物を、上述の噴霧乾燥粉体に含有させて焼成前駆体としてもよい。
本発明のリチウム二次電池用正極は、本発明のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体及び結着剤を含有する正極活物質層を集電体上に形成してなるものである。
正極のプレス後の電極密度としては、下限としては、通常、2.2g/cm3以上、好ましくは2.4g/cm3以上、特に好ましくは2.6g/cm3以上、上限としては、通常、4.2g/cm3以下、好ましくは4.0g/cm3以下、特に好ましくは3.8g/cm3以下である。
なお、塗布、乾燥によって得られた正極活物質層は、正極活物質の充填密度を上げるために、ローラープレス等により圧密化することが好ましい。
かくして、本発明のリチウム二次電池用正極が調製できる。
本発明のリチウム二次電池は、リチウムを吸蔵・放出可能な上記の本発明のリチウム二次電池用正極と、リチウムを吸蔵・放出可能な負極と、リチウム塩を電解塩とする非水電解質とを備える。更に、正極と負極との間に、非水電解質を保持するセパレータを備えていても良い。正極と負極との接触による短絡を効果的に防止するには、このようにセパレータを介在させるのが望ましい。
負極は通常、正極と同様に、負極集電体上に負極活物質層を形成して構成される。
負極集電体の材質としては、銅、ニッケル、ステンレス鋼、ニッケルメッキ鋼等の金属材料や、カーボンクロス、カーボンペーパー等の炭素材料が用いられる。中でも金属材料の場合、金属箔、金属円柱、金属コイル、金属板、金属薄膜等が、炭素材料の場合、炭素板、炭素薄膜、炭素円柱等が挙げられる。中でも、金属薄膜が、現在工業化製品に使用されていることから好ましい。なお、薄膜は適宜メッシュ状に形成しても良い。負極集電体として金属薄膜を使用する場合、その好適な厚さの範囲は、正極集電体について上述した範囲と同様である。
炭素材料としては、その種類に特に制限はないが、人造黒鉛、天然黒鉛等の黒鉛(グラファイト)や、様々な熱分解条件での有機物の熱分解物が挙げられる。有機物の熱分解物としては、石炭系コークス、石油系コークス、石炭系ピッチの炭化物、石油系ピッチの炭化物、或いはこれらピッチを酸化処理したものの炭化物、ニードルコークス、ピッチコークス、フェノール樹脂、結晶セルロース等の炭化物等及びこれらを一部黒鉛化した炭素材、ファーネスブラック、アセチレンブラック、ピッチ系炭素繊維等が挙げられる。中でも黒鉛が好ましく、特に好適には、種々の原料から得た易黒鉛性ピッチに高温熱処理を施すことによって製造された、人造黒鉛、精製天然黒鉛、又はこれらの黒鉛にピッチを含む黒鉛材料等であって、種々の表面処理を施したものが主として使用される。これらの炭素材料は、それぞれ1種を単独で用いても良いし、2種以上を組み合わせて用いても良い。
また、黒鉛材料の灰分が、黒鉛材料の重量に対して通常1重量%以下、中でも0.5重量%以下、特に0.1重量%以下であることが好ましい。
また、レーザー回折・散乱法により求めた黒鉛材料のメジアン径が、通常1μm以上、中でも3μm以上、更には5μm以上、特に7μm以上、また、通常100μm以下、中でも50μm以下、更には40μm以下、特に30μm以下であることが好ましい。
更に、黒鉛材料についてアルゴンレーザー光を用いたラマンスペクトル分析を行った場合に、1580~1620cm-1の範囲で検出されるピークPAの強度IAと、1350~1370cm-1の範囲で検出されるピークPBの強度IBとの強度比IA/IBが、0以上0.5以下であるものが好ましい。また、ピークPAの半価幅は26cm-1以下が好ましく、25cm-1以下がより好ましい。
非水電解質としては、例えば公知の有機電解液、高分子固体電解質、ゲル状電解質、無機固体電解質等を用いることができるが、中でも有機電解液が好ましい。有機電解液は、有機溶媒に溶質(電解質)を溶解させて構成される。
さらに、有機電解液中には、ジフルオロリン酸リチウムなど、サイクル寿命や出力特性の向上に効果を発揮する添加剤や、プロパンスルトンやプロペンスルトンなどの高温保存ガスの抑制に効果を発揮する添加剤を任意の割合で添加してもよい。
電解質として前述の有機電解液を用いる場合には、電極同士の短絡を防止するために、正極と負極との間にセパレータが介装される。セパレータの材質や形状は特に制限されないが、使用する有機電解液に対して安定で、保液性に優れ、且つ、電極同士の短絡を確実に防止できるものが好ましい。好ましい例としては、各種の高分子材料からなる微多孔性のフィルム、シート、不織布等が挙げられる。高分子材料の具体例としては、ナイロン、セルロースアセテート、ニトロセルロース、ポリスルホン、ポリアクリロニトリル、ポリフッ化ビニリデン、ポリプロピレン、ポリエチレン、ポリブテン等のポリオレフィン高分子が用いられる。特に、セパレータの重要な因子である化学的及び電気化学的な安定性の観点からは、ポリオレフィン系高分子が好ましく、電池におけるセパレータの使用目的の一つである自己閉塞温度の点からは、ポリエチレンが特に望ましい。
本発明のリチウム二次電池は、上述した本発明のリチウム二次電池用正極と、負極と、電解質と、必要に応じて用いられるセパレータとを、適切な形状に組み立てることにより製造される。更に、必要に応じて外装ケース等の他の構成要素を用いることも可能である。
本発明のリチウム二次電池の形状は特に制限されず、一般的に採用されている各種形状の中から、その用途に応じて適宜選択することができる。一般的に採用されている形状の例としては、シート電極及びセパレータをスパイラル状にしたシリンダータイプ、ペレット電極及びセパレータを組み合わせたインサイドアウト構造のシリンダータイプ、ペレット電極及びセパレータを積層したコインタイプなどが挙げられる。また、電池を組み立てる方法も特に制限されず、目的とする電池の形状に合わせて、通常用いられている各種方法の中から適宜選択することができる。
本発明のリチウム二次電池は、後述の実施例においては、満充電状態における正極の充電電位が4.4V(vs.Li/Li+)以上となるように設計されている電池で特に効果を奏する。即ち、本発明のリチウム二次電池正極材料用リチウムニッケルマンガンコバルト系複合酸化物粉体は、高い充電電位で充電するように設計されたリチウム二次電池として使用した場合において、本願発明の効果を有効に発揮する。しかし、4.4V(vs.Li/Li+)未満の低電位においても、十分に効果を発揮する。
後述の各実施例及び比較例において製造されたリチウム遷移金属系化合物粉体の物性等は、各々次のようにして測定した。
Physical Electronics社製 X線光電子分光装置「ESCA-5700」を用い、下記条件で行った。
X線源:単色化AlKα
分析面積:0.8mm径
取り出し角:45°
定量方法:Bls、Mn2P1/2、Co2P3/2、Ni2P3/2、Nb3d、Mo3d、Sn3d5/2、W4f、P2P各ピークの面積を感度係数で補正。
日本電子(株)製 クロスセクションポリッシャー(SM-09010)を用いて、加速電圧5kVの条件で、二次粒子の断面を作製した。
HITACHI製 走査型電子顕微鏡(SU-70)を用いて、電子銃加速電圧:3kVでSEM観察を行った。なお、観察モードとしては、YAG型反射電子検出器を用いて観察を実施した(以後、得られた像は反射電子像と記載)。
OXFORD INSTRUMENTS INCA Energyを用いて、電子銃加速電圧:3kVでSEM-EDX分析を行った。
公知のレーザー回折/散乱式粒度分布測定装置を用い、屈折率を1.60に設定し、粒子径基準を体積基準として測定した。また、分散媒としては0.1重量%ヘキサメタリン酸ナトリウム水溶液を用い測定を行った。
10,000倍のSEM画像により求めた。
水銀圧入法による測定装置としては、Micromeritics社製オートポアIII9450型を用いた。また、水銀圧入法の測定条件としては、室温で3.86kPaから413MPaまで昇圧しながら測定を行った。なお、水銀の表面張力の値としては480dyn/cm、接触角の値としては141.3°を用いた。
試料粉体10gを10mlのガラス製メスシリンダーに入れ、ストローク約20mmで200回タップした時の粉体充填密度として求めた。
BET法により求めた。
公知のレーザー回折/散乱式粒度分布測定装置を用い、屈折率を1.24に設定し、粒子径基準を体積基準として測定した。また、分散媒としては0.1重量%ヘキサメタリン酸ナトリウム水溶液を用い、5分間の超音波分散(出力30W、周波数22.5kHz)後に測定を行った。
(実施例1)
Li2CO3、NiCO3、Mn3O4、CoOOH、H3BO3、WO3、Li2SO4を、Li:Ni:Mn:Co:B:W:S=1.12:0.45:0.45:0.10:0.0025:0.015:0.0075のモル比となるように秤量し、混合した後、これに純水を加えてスラリーを調製した。このスラリーを攪拌しながら、循環式媒体攪拌型湿式粉砕機を用いて、スラリー中の固形分をメジアン径0.50μmに粉砕した。
Li2CO3、NiCO3、Mn3O4、CoOOH、H3BO3、WO3、Li2SO4を、Li:Ni:Mn:Co:B:W:S=1.12:0.45:0.45:0.10:0.0025:0.015:0.0075のモル比となるように秤量し、混合した後、これに純水を加えてスラリーを調製した。このスラリーを攪拌しながら、循環式媒体攪拌型湿式粉砕機を用いて、スラリー中の固形分をメジアン径0.50μmに粉砕した。
Li2CO3、NiCO3、Mn3O4、CoOOH、H3BO3、WO3、Li2SO4を、Li:Ni:Mn:Co:B:W:S=1.15:0.45:0.45:0.10:0.0025:0.015:0.0075のモル比となるように秤量し、混合した後、これに純水を加えてスラリーを調製した。このスラリーを攪拌しながら、循環式媒体攪拌型湿式粉砕機を用いて、スラリー中の固形分をメジアン径0.50μmに粉砕した。
(比較例1)
Li2CO3、NiCO3、Mn3O4、CoOOH、H3BO3、WO3を、Li:Ni:Mn:Co:B:W=1.12:0.45:0.45:0.10:0.0025:0.015のモル比となるように秤量し、混合した後、これに純水を加えてスラリーを調製した。このスラリーを攪拌しながら、循環式媒体攪拌型湿式粉砕機を用いて、スラリー中の固形分をメジアン径0.50μmに粉砕した。
Li2CO3、NiCO3、Mn3O4、CoOOH、H3BO3、WO3を、Li:Ni:Mn:Co:B:W=1.12:0.45:0.45:0.10:0.0025:0.015のモル比となるように秤量し、混合した後、これに純水を加えてスラリーを調製した。このスラリーを攪拌しながら、循環式媒体攪拌型湿式粉砕機を用いて、スラリー中の固形分をメジアン径0.50μmに粉砕した。
Li2CO3、NiCO3、Mn3O4、CoOOH、H3BO3、WO3を、Li:Ni:Mn:Co:B:W=1.15:0.45:0.45:0.10:0.0025:0.015のモル比となるように秤量し、混合した後、これに純水を加えてスラリーを調製した。このスラリーを攪拌しながら、循環式媒体攪拌型湿式粉砕機を用いて、スラリー中の固形分をメジアン径0.50μmに粉砕した。
上述の実施例及び比較例で製造したリチウム遷移金属系化合物粉体をそれぞれ正極材料(正極活物質)として用いて、以下の方法によりリチウム二次電池を作製し、評価を行った。
(1)レート試験:
実施例及び比較例で製造した混合粉体又は非混合粉体の各々75重量%、アセチレンブラック20重量%、及びポリテトラフルオロエチレンパウダー5重量%の割合で秤量したものを乳鉢で十分混合し、薄くシート状にしたものを9mmφのポンチを用いて打ち抜いた。この際、全体重量は約8mgになるように調整した。これをアルミニウムエキスパンドメタルに圧着して、9mmφの正極とした。
実施例及び比較例で製造した混合粉体又は非混合粉体を各々75重量%、アセチレンブラック20重量%、及びポリテトラフルオロエチレンパウダー5重量%の割合で秤量したものを乳鉢で十分混合し、薄くシート状にしたものを12mmφのポンチを用いて打ち抜いた。この際、全体重量は約18mgになるように調整した。これをアルミニウムエキスパンドメタルに圧着して、12mmφの正極とした。
=(Qf[mAh/g]/1.2)Qs(C)[mAh/g]
1C[mA] = Qs(D)×正極活物質重量[g]/時間[h]
まず、室温で定電流0.2C充放電2サイクル及び定電流1C充放電1サイクルを行った。なお、充電上限は4.1V、下限電圧は3.0Vとした。 次に、60℃の高温で定電流0.2C充放電1サイクル、ついで定電流1C充放電100サイクルの試験を行った。なお、充電上限は4.1V、下限電圧は3.0Vとした。この時、60℃での1C充放電100サイクル目の放電容量Qh(100)の割合を、下記の式で高温サイクル容量維持率(サイクル維持率)Pとして算出し、この値で電池の高温特性を比較した。
表2に、実施例及び比較例のリチウム二次電池用正極活物質材料をそれぞれ使用した電池の60℃でのサイクル維持率(P)を示す。
まず、60℃での1Cサイクル前後に、1/3C定電流充放電により、充電深度40%に調整したコインセルを-30℃の低温雰囲気に1時間以上保持した後、定電流0.5C[mA]で10秒間放電させた時の10秒後の電圧をV[mV]、放電前の電圧をV0[mV]とした時、ΔV=V-V0として下式より抵抗値R[Ω]を算出した。
60℃、1Cでの100サイクル後抵抗増加率は下式より抵抗値R[Ω]を算出した。
抵抗増加率[%]=100サイクル後の抵抗R1/サイクル前の抵抗R2×100
これにより、電極面積当りでの電池容量(容量密度)が大きく、高容量化ができることが分かる。
Claims (21)
- リチウムイオンの挿入・脱離が可能な機能を有するリチウム遷移金属系化合物を含む粉体であって、該粉体の粒子の内部に、周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素、並びに、第5周期及び第6周期の第5~7族元素から選ばれる少なくとも1種の元素に由来するSEM-EDX法によるピークを有する化合物を含むリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
- リチウム遷移金属系化合物が、二種以上の組成を持つ一次粒子から構成される二次粒子からなる粉体であって、二次粒子の少なくとも内部に、周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素、並びに、第5周期及び第6周期の第5~7族元素から選ばれる少なくとも1種の元素に由来するSEM-EDX法によるピークを有する化合物の一次粒子を含む請求項1に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
- リチウムイオンの挿入・脱離が可能な機能を有するリチウム遷移金属系化合物を含み、該リチウム遷移金属系化合物の原料となるリチウム源及び遷移金属源と、構造式中に周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素を有する化合物とを、粉砕及び混合した後、焼成することにより得られる、リチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
- リチウムイオンの挿入・脱離が可能な機能を有するリチウム遷移金属系化合物を含み、該リチウム遷移金属系化合物の原料に、周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素を有する化合物並びに第5周期及び第6周期の第5~7族元素から選ばれる少なくとも1種の元素を有する化合物を添加して焼成することにより得られる、リチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
- 前記周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素が、S、Se、Te及びPoからなる群より選ばれる少なくとも一種の元素である請求項1ないし4のいずれか1項に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
- 前記周期表第5周期及び第6周期の第5~7族元素から選ばれる少なくとも1種の元素が、Mo、W、Nb、Ta及びReからなる群より選ばれる少なくとも一種の元素である請求項1ないし5のいずれか1項に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
- 前記リチウム遷移金属系化合物が、細孔分布曲線において、細孔半径80nm以上800nm未満にピークを有する請求項1ないし6のいずれか1項に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
- 二次粒子の表面部分のLi、S、Se、Te、Po、Mo、W、Nb、Ta及びRe元素以外の金属元素の合計に対するS、Se、Te及びPo元素の合計のモル比が、二次粒子全体の該モル比の500倍以下である請求項2ないし7のいずれか1項に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
- 二次粒子の表面部分のLi、S、Se、Te、Po、Mo、W、Nb、Ta及びRe元素以外の金属元素の合計に対するMo、W、Nb、Ta及びRe元素の合計のモル比が、二次粒子全体の該モル比の1.05倍以上である請求項2ないし8のいずれか1項に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
- BET比表面積が0.5m2/g以上、3m2/g以下である請求項1ないし9のいずれか1項に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
- 嵩密度が1.2g/cm3以上、2.8g/cm3以下である請求項1ないし10のいずれか1項に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
- 前記リチウム遷移金属系化合物が、層状構造を有するリチウムニッケルマンガンコバルト系複合酸化物又はスピネル構造を有するリチウムマンガン系複合酸化物である、請求項1ないし11のいずれか1項に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
- 組成が、下記組成式(A)又は(B)で示される請求項12に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
Li1+xMO2 ・・・(A)
(ただし、上記式(A)中、xは0以上、0.5以下、Mは、Li、Ni及びMn、又は、Li、Ni、Mn及びCoから構成される元素であり、Mn/Niモル比は0.1以上、5以下、Co/(Mn+Ni+Co)モル比は0以上、0.35以下、M中のLiモル比は0.001以上、0.2以下である。)
Li[LiaM’bMn2-b-a]O4+δ・・・(B)
(ただし、上記式(B)中、a、b及びδは、0≦a≦0.3、0.4≦b≦0.6、-0.5≦δ≦0.5を満たし、M’は、Ni、Cr、Fe、Co及びCuから選ばれる遷移金属のうちの少なくとも1種を表す。) - 酸素含有ガス雰囲気下において、焼成温度1000℃以上で焼成して得られる請求項1ないし13のいずれか1項に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
- さらに、Mo、W、Nb、Ta及びReから選ばれる少なくとも1種の元素を含有する化合物と、B及びBiから選ばれる少なくとも1種の元素を含有する化合物とを併用添加した後、焼成して得られる請求項1ないし14のいずれか1項に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体。
- リチウム化合物と、Mn、Co、及びNiから選ばれる少なくとも1種の遷移金属化合物と、周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素を含有する化合物とを、液体媒体中で粉砕し、これらを均一に分散させたスラリーを調製する工程と、該スラリーを噴霧乾燥する噴霧乾燥工程と、得られた噴霧乾燥体を焼成する焼成工程とを含むリチウム二次電池正極材料用リチウム遷移金属系化合物粉体の製造方法。
- スラリー調製工程において、リチウム化合物と、前記遷移金属化合物と、前記周期表第3周期以降の第16族元素から選ばれる少なくとも一種の元素を含有する化合物とを、液体媒体中で、下記条件に従って測定するメジアン径が0.6μm以下になるまで粉砕し、
噴霧乾燥工程において、噴霧乾燥時のスラリー粘度をV(cP)、スラリー供給量をS(L/min)、ガス供給量をG(L/min)とした際、50cP≦V≦7000cP、500≦G/S≦10000となる条件で噴霧乾燥を行う請求項16に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体の製造方法。
(メジアン径測定条件は下記に従う。
i)出力30W、周波数22.5kHzの超音波分散を5分間行った後、
ii)レーザー回折/散乱式粒度分布測定装置によって、屈折率を1.24に設定し、粒子径基準を体積基準として、メジアン径を測定する) - 前記遷移金属化合物として少なくともニッケル化合物、マンガン化合物及びコバルト化合物を含み、前記焼成工程において、前記噴霧乾燥体を、酸素含有ガス雰囲気下、1000℃以上で焼成する請求項16又は17に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体の製造方法。
- リチウム化合物が炭酸リチウムである請求項16ないし18のいずれか1項に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体の製造方法。
- 請求項1ないし15のいずれか1項に記載のリチウム二次電池正極材料用リチウム遷移金属系化合物粉体及び結着剤を含有する正極活物質層と集電体とを有するリチウム二次電池用正極。
- リチウムを吸蔵・放出可能な負極、リチウム塩を含有する非水電解質、及びリチウムを吸蔵・放出可能な正極を備えたリチウム二次電池であって、正極が請求項20に記載のリチウム二次電池用正極であるリチウム二次電池。
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Cited By (4)
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JP2014044945A (ja) * | 2012-08-03 | 2014-03-13 | Gs Yuasa Corp | リチウム二次電池用正極活物質、その製造方法、リチウム二次電池用電極、リチウム二次電池 |
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Publication number | Priority date | Publication date | Assignee | Title |
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TW202036966A (zh) * | 2019-03-22 | 2020-10-01 | 宏總科技股份有限公司 | 二次電池正極材料製備方法 |
WO2021195524A1 (en) * | 2020-03-27 | 2021-09-30 | Board Of Regents, The University Of Texas System | Low-cobalt and cobalt-free, high-energy cathode materials for lithium batteries |
JP7060649B2 (ja) | 2020-05-22 | 2022-04-26 | Basf戸田バッテリーマテリアルズ合同会社 | 非水電解質二次電池用正極活物質の製造方法 |
WO2023131987A1 (ja) * | 2022-01-04 | 2023-07-13 | 株式会社 東芝 | 電極、電池、及び電池パック |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH09245787A (ja) | 1996-03-07 | 1997-09-19 | Kansai Shokubai Kagaku Kk | リチウム二次電池用正極活物質 |
JP2001006672A (ja) | 1999-06-23 | 2001-01-12 | Sanyo Electric Co Ltd | 活物質、電極、非水電解液二次電池及び活物質の製造方法 |
JP2003297360A (ja) | 2002-04-05 | 2003-10-17 | Merck Ltd | 非水電解質二次電池用正極活物質及びその製造方法 |
JP2004014296A (ja) * | 2002-06-06 | 2004-01-15 | Nichia Chem Ind Ltd | リチウムイオン二次電池用正極活物質 |
JP2006172753A (ja) | 2004-12-13 | 2006-06-29 | Mitsubishi Chemicals Corp | リチウム二次電池正極材料用リチウムニッケルマンガン系複合酸化物粉体及びその製造方法、並びにそれを用いたリチウム二次電池用正極及びリチウム二次電池 |
JP2006523368A (ja) * | 2003-04-03 | 2006-10-12 | ヴァレンス テクノロジー インコーポレーテッド | 混合粒子を含む電極 |
JP2007335331A (ja) | 2006-06-16 | 2007-12-27 | Sony Corp | 正極活物質およびその製造方法、正極およびその製造方法ならびに二次電池 |
JP2009104794A (ja) * | 2007-10-19 | 2009-05-14 | Toyota Central R&D Labs Inc | リチウム二次電池用活物質、その製造方法及びリチウム二次電池 |
JP2009289758A (ja) * | 2006-12-26 | 2009-12-10 | Mitsubishi Chemicals Corp | リチウム遷移金属系化合物粉体、その製造方法、及びその焼成前駆体となる噴霧乾燥体、並びにそれを用いたリチウム二次電池用正極及びリチウム二次電池 |
JP2010505732A (ja) * | 2006-10-13 | 2010-02-25 | トダ・コウギョウ・ヨーロッパ・ゲゼルシャフト・ミット・ベシュレンクテル・ハフツング | 化合物粉体、その製造方法およびリチウム二次電池へのその使用 |
JP2010085563A (ja) | 2008-09-30 | 2010-04-15 | Seiko Epson Corp | 画像調整装置、画像表示システム及び画像調整方法 |
Family Cites Families (35)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5290592A (en) * | 1990-02-13 | 1994-03-01 | Yuasa Battery Co., Ltd. | Manufacturing method for electrode |
US20030211390A1 (en) * | 2000-12-22 | 2003-11-13 | Dahn Jeffrey R. | Grain boundary materials as electrodes for lithium ion cells |
US7026068B2 (en) | 2001-12-19 | 2006-04-11 | Nichia Corporation | Positive electrode active material for lithium ion secondary battery |
CN100359725C (zh) | 2002-03-28 | 2008-01-02 | 三菱化学株式会社 | 锂二次电池的正极材料、采用它的锂二次电池及制备锂二次电池正极材料的方法 |
US7241532B2 (en) | 2002-03-28 | 2007-07-10 | Mitsubishi Chemical Corporation | Positive-electrode material for lithium secondary battery, secondary battery employing the same, and process for producing positive-electrode material for lithium secondary battery |
US8092940B2 (en) * | 2002-05-08 | 2012-01-10 | Gs Yuasa International Ltd. | Non-aqueous electrolyte secondary battery |
BR0315457B1 (pt) * | 2002-11-29 | 2012-06-26 | eletrodo negativo para bateria secundária não-aquosa, processo de produção de eletrodo negativo, e bateria secundária não-aquosa. | |
US20070141468A1 (en) | 2003-04-03 | 2007-06-21 | Jeremy Barker | Electrodes Comprising Mixed Active Particles |
WO2004102702A1 (ja) | 2003-05-13 | 2004-11-25 | Mitsubishi Chemical Corporation | 層状リチウムニッケル系複合酸化物粉体及びその製造方法 |
WO2005031899A1 (ja) | 2003-09-26 | 2005-04-07 | Mitsubishi Chemical Corporation | リチウム二次電池正極材用リチウム複合酸化物粒子、並びにそれを用いたリチウム二次電池用正極及びリチウム二次電池 |
JP2005108448A (ja) | 2003-09-26 | 2005-04-21 | Nichia Chem Ind Ltd | 非水電解質二次電池用正極副活物質、非水電解質二次電池用正極活物質、非水電解質二次電池および非水電解質二次電池の製造方法 |
US10629947B2 (en) * | 2008-08-05 | 2020-04-21 | Sion Power Corporation | Electrochemical cell |
JP4110533B2 (ja) * | 2004-02-27 | 2008-07-02 | 日立金属株式会社 | Mo系ターゲット材の製造方法 |
EP1742281B1 (en) | 2004-04-27 | 2011-09-07 | Mitsubishi Chemical Corporation | Layered lithium nickel manganese cobalt composite oxide powder for material of positive electrode of lithium secondary battery, process for producing the same, positive electrode of lithium secondary battery therefrom, and lithium secondary battery |
KR100639526B1 (ko) | 2005-02-02 | 2006-10-30 | 한양대학교 산학협력단 | 탄산염 공침법을 이용한 3볼트급 스피넬 산화물, 그제조방법 및 이를 이용한 리튬이차전지 |
CN101151748B (zh) | 2005-02-08 | 2010-10-06 | 三菱化学株式会社 | 锂二次电池及其正极材料 |
KR20130090913A (ko) * | 2005-10-20 | 2013-08-14 | 미쓰비시 가가꾸 가부시키가이샤 | 리튬 2 차 전지 및 그것에 사용하는 비수계 전해액 |
WO2007116971A1 (ja) | 2006-04-07 | 2007-10-18 | Mitsubishi Chemical Corporation | リチウム二次電池正極材料用リチウム遷移金属系化合物粉体、その製造方法、その噴霧乾燥体およびその焼成前駆体、並びに、それを用いたリチウム二次電池用正極およびリチウム二次電池 |
JP4635978B2 (ja) * | 2006-08-02 | 2011-02-23 | ソニー株式会社 | 負極及び二次電池 |
JP4613943B2 (ja) | 2006-11-10 | 2011-01-19 | 三菱化学株式会社 | リチウム遷移金属系化合物粉体、その製造方法、及びその焼成前躯体となる噴霧乾燥体、並びにそれを用いたリチウム二次電池用正極及びリチウム二次電池 |
CN101584062B (zh) * | 2006-12-26 | 2015-11-25 | 株式会社三德 | 非水电解质二次电池用正极活性物质、正极以及二次电池 |
US8197964B2 (en) * | 2007-07-09 | 2012-06-12 | Sony Corporation | Battery |
WO2009031619A1 (ja) | 2007-09-04 | 2009-03-12 | Mitsubishi Chemical Corporation | リチウム遷移金属系化合物粉体、その製造方法及びその焼成前駆体となる噴霧乾燥体、並びに、それを用いたリチウム二次電池用正極及びリチウム二次電池 |
DE102007048289A1 (de) * | 2007-10-08 | 2009-04-09 | Universität Siegen | Lithium-Argyrodite |
JP5470700B2 (ja) * | 2007-12-10 | 2014-04-16 | 住友大阪セメント株式会社 | 電極材料およびその製造方法、並びに、電極および電池 |
KR100911999B1 (ko) * | 2008-01-28 | 2009-08-14 | 주식회사 엘지화학 | 절연특성이 향상된 전지 |
JP2010064907A (ja) * | 2008-09-09 | 2010-03-25 | Sumitomo Metal Mining Co Ltd | リチウム遷移金属複合酸化物とその製造方法およびそれを用いたリチウムイオン二次電池 |
JP2011096630A (ja) * | 2009-10-02 | 2011-05-12 | Sanyo Electric Co Ltd | 固体リチウム二次電池及びその製造方法 |
FR2951876B1 (fr) * | 2009-10-26 | 2012-02-03 | Commissariat Energie Atomique | Micro-batterie au lithium munie d'une couche d'encapsulation conductrice electroniquement |
JP5638232B2 (ja) * | 2009-12-02 | 2014-12-10 | 住友金属鉱山株式会社 | 非水系電解質二次電池正極活物質用ニッケルコバルトマンガン複合水酸化物粒子とその製造方法、非水系電解質二次電池用正極活物質とその製造方法、および非水系電解質二次電池 |
JP5659696B2 (ja) * | 2009-12-24 | 2015-01-28 | ソニー株式会社 | リチウムイオン二次電池、リチウムイオン二次電池用負極、電動工具、電気自動車および電力貯蔵システム |
WO2011083861A1 (ja) | 2010-01-08 | 2011-07-14 | 三菱化学株式会社 | リチウム二次電池正極材料用粉体及びその製造方法、並びにそれを用いたリチウム二次電池用正極及びリチウム二次電池 |
CN102754251A (zh) * | 2010-02-12 | 2012-10-24 | 丰田自动车株式会社 | 锂二次电池用正极活性物质 |
EP2544280B1 (en) * | 2010-03-05 | 2018-06-06 | JX Nippon Mining & Metals Corporation | Positive-electrode active material for lithium ion battery, positive electrode for lithium battery, and lithium ion battery |
JP5621753B2 (ja) * | 2011-11-15 | 2014-11-12 | 信越化学工業株式会社 | リチウムイオン電池用負極材 |
-
2011
- 2011-03-30 KR KR1020127025320A patent/KR101858763B1/ko active IP Right Grant
- 2011-03-30 JP JP2011075479A patent/JP2011228292A/ja not_active Withdrawn
- 2011-03-30 CN CN2011800172799A patent/CN102823033A/zh active Pending
- 2011-03-30 EP EP11765622.3A patent/EP2555287B1/en not_active Not-in-force
- 2011-03-30 WO PCT/JP2011/057986 patent/WO2011125722A1/ja active Application Filing
-
2012
- 2012-10-01 US US13/632,787 patent/US9225005B2/en not_active Expired - Fee Related
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH09245787A (ja) | 1996-03-07 | 1997-09-19 | Kansai Shokubai Kagaku Kk | リチウム二次電池用正極活物質 |
JP2001006672A (ja) | 1999-06-23 | 2001-01-12 | Sanyo Electric Co Ltd | 活物質、電極、非水電解液二次電池及び活物質の製造方法 |
JP2003297360A (ja) | 2002-04-05 | 2003-10-17 | Merck Ltd | 非水電解質二次電池用正極活物質及びその製造方法 |
JP2004014296A (ja) * | 2002-06-06 | 2004-01-15 | Nichia Chem Ind Ltd | リチウムイオン二次電池用正極活物質 |
JP2006523368A (ja) * | 2003-04-03 | 2006-10-12 | ヴァレンス テクノロジー インコーポレーテッド | 混合粒子を含む電極 |
JP2006172753A (ja) | 2004-12-13 | 2006-06-29 | Mitsubishi Chemicals Corp | リチウム二次電池正極材料用リチウムニッケルマンガン系複合酸化物粉体及びその製造方法、並びにそれを用いたリチウム二次電池用正極及びリチウム二次電池 |
JP2007335331A (ja) | 2006-06-16 | 2007-12-27 | Sony Corp | 正極活物質およびその製造方法、正極およびその製造方法ならびに二次電池 |
JP2010505732A (ja) * | 2006-10-13 | 2010-02-25 | トダ・コウギョウ・ヨーロッパ・ゲゼルシャフト・ミット・ベシュレンクテル・ハフツング | 化合物粉体、その製造方法およびリチウム二次電池へのその使用 |
JP2009289758A (ja) * | 2006-12-26 | 2009-12-10 | Mitsubishi Chemicals Corp | リチウム遷移金属系化合物粉体、その製造方法、及びその焼成前駆体となる噴霧乾燥体、並びにそれを用いたリチウム二次電池用正極及びリチウム二次電池 |
JP2009104794A (ja) * | 2007-10-19 | 2009-05-14 | Toyota Central R&D Labs Inc | リチウム二次電池用活物質、その製造方法及びリチウム二次電池 |
JP2010085563A (ja) | 2008-09-30 | 2010-04-15 | Seiko Epson Corp | 画像調整装置、画像表示システム及び画像調整方法 |
Non-Patent Citations (1)
Title |
---|
See also references of EP2555287A4 |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2013142624A (ja) * | 2012-01-11 | 2013-07-22 | Jeol Ltd | 試料作製方法 |
EP2692693A1 (en) * | 2012-08-03 | 2014-02-05 | GS Yuasa International Ltd. | Positive active material for lithium secondary battery, manufacturing method thereof, lithium secondary battery electrode, and lithium secondary battery |
CN103579606A (zh) * | 2012-08-03 | 2014-02-12 | 株式会社杰士汤浅国际 | 锂二次电池用正极活性物质、其制造方法、锂二次电池用电极及锂二次电池 |
JP2014044945A (ja) * | 2012-08-03 | 2014-03-13 | Gs Yuasa Corp | リチウム二次電池用正極活物質、その製造方法、リチウム二次電池用電極、リチウム二次電池 |
CN103579606B (zh) * | 2012-08-03 | 2017-05-03 | 株式会社杰士汤浅国际 | 锂二次电池用正极活性物质、其制造方法、锂二次电池用电极及锂二次电池 |
CN110112366A (zh) * | 2019-06-18 | 2019-08-09 | 珠海冠宇电池有限公司 | 一种锂离子电池极片及锂离子电池 |
Also Published As
Publication number | Publication date |
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KR101858763B1 (ko) | 2018-05-16 |
US9225005B2 (en) | 2015-12-29 |
KR20130076795A (ko) | 2013-07-08 |
EP2555287A1 (en) | 2013-02-06 |
US20130029216A1 (en) | 2013-01-31 |
EP2555287B1 (en) | 2018-05-02 |
EP2555287A4 (en) | 2015-08-19 |
CN102823033A (zh) | 2012-12-12 |
JP2011228292A (ja) | 2011-11-10 |
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