JPH0666141B2 - Non-aqueous secondary battery - Google Patents

Description

TECHNICAL FIELD The present invention relates generally to lithium batteries, and more particularly to batteries having a non-aqueous electrolyte and an anode composed of a mixed metal oxide.

Background of the Invention In recent years, there has been a great deal of interest in non-aqueous batteries because of their desirable properties such as high energy and volume density, they are used in small electronic applications such as calculators, circuit boards and watches. This is because it is possible to manufacture a particularly useful battery. Also, such a battery could overcome some of the drawbacks of the nickel-cadmium batteries now in widespread use, such as self-discharge and relatively low voltage. The non-aqueous battery can be a primary battery, that is, a battery that is manufactured in a charged state and is only discharged, or a secondary battery, that is, a battery that can be recharged after discharging.

Many materials are considered as candidates for electrode materials in non-aqueous batteries. The cathode typically contains an alkali metal such as lithium or sodium, although other materials are contemplated. The anode is selected from a wide variety of materials. Materials of the type that undergo topochemical changes (chemical reactions controlled by the shape of the structure) are particularly attractive because they are promising as active anode materials in secondary batteries. Topochemical changes are broadly defined as host-lattice-related reactions in which a guest species is inserted into the host lattice and the resulting structure retains the essential structural features of the host lattice. Has been done. In many topochemical changes, the structural changes are minimal and the process is called insertion. The insertion process appears to occur reversibly easily and can form the basis of secondary batteries if the change is in the oxidation-reduction type.

Currently, the topochemical changes of alkali metals and certain transition metal compounds are particularly promising candidates for secondary battery applications.
The use of layered transition metal selenides and sulfides as the active anode material in such cells has received much interest. However, all other factors being equal, transition metal oxides are preferred over sulphides and selenides because of the higher energy density obtained per unit weight and / or unit volume. Moreover, oxides are less harmful when decomposed than sulfides and selenides.

Several types of transition metal oxides have been investigated for electrode applications. For example, as described in U.S. Pat. No. 3,655,585, by Dey et al., And Electrochemical Society Meeting, Research Presentation No. Two
7. Toronto, V ₂ O by Walk and Gore as announced on May 11-16, 1975.
₅ is used for the primary battery. However, since these materials are adversely affected by irreversible reduction at low voltage and electrolyte oxidation during charging, they are generally not so important as electrode materials for secondary batteries. VO ₂ (B)
And the general formula VO _{2 + y} (where y is greater than 0.0,
It is 0.4 or less. Vanadium oxide containing compounds of (4) is used in secondary batteries as disclosed by Christian, Disalvo and Murphy in US Pat. No. 4,228,226. These oxides have an open, closely related shear structure, which results in a topochemical transformation with lithium. As used herein, "open shear structure" means having pores, interstices or cracks (open) that are available for in-situ addition without lattice of these oxides, "close contact". By "in relation to" is meant simply that it is a small group limited by similar special cases such as MO ₂ and MO ₃ oxides. Some tungsten oxides show topochemical lithium uptake. For example, K. H. Chang and M.D. S. See Wittingham, Solid State Ionics, 1, 151-156 (1980). RuO ₂ , OsO ₂ , IrO ₂ , Mo having a rutile structure
Transition metal oxides such as O ₂ , WO ₂ and VO ₂ are described in US Pat. No. 4,198,476,
Used by Disalvo and Murphy as an anode material for secondary batteries.

SUMMARY OF THE INVENTION The non-aqueous battery of the present invention has a nominal atomic stoichiometry.
ichiometry) xM ^A O ₂ · yM ^B ₂ O ₅ · zM ^C O
₃ (wherein at least two of x, y and z are not zero, z + y + z = 1.0, and at least two kinds of metals are present), and a substance having a crystal structure of a Wadsley phase And at least one mixed metal oxide such as vanadium tungsten oxide is used as the anode material and lithium is used as the cathode material.
In a preferred embodiment, M ^A is at least one element selected from Groups IVB, VB and VIB of the Periodic Table, and M ^B is at least selected from the group consisting of elements of Groups VB and VIB of the Periodic Table. One element, M ^C is at least one element selected from the VIB group of the periodic table. In another preferred embodiment, M ^A and M ^B are V and M ^C is W. In another preferred embodiment, the active anode material has a nominal atomic stoichiometry of V ₂₊ δW _1-
δO _7.5 (where δ is 0.0 or more and 0.2 or less). These limits are: for δ = 0.0, x = 0.4, y = 0.2, and z = 0.4, δ
= 0.2, x = 0.348, y = 0.30
4 and z = 0.348. In yet another preferred embodiment, the active anode material has a nominal atomic stoichiometry W _0.6 V _2.4 O ₇ , for which x =
0.615, y = 0.154 and z = 0231. In another preferred embodiment, M ^B is Nb and M ^A is Ti. In another preferred embodiment, x
Is 0.05 to 0.5, y is 0.5 to 0.95, and z is 0.0.

The composition contained is limited to the stoichiometric formulas (M ^A ) O ₂ and (M ^A ).
^C ) Includes a series of closely related shear structures between O ₃ . These shear structures have an open framework with tunnels and voids that can be used for lithium transport and coordination.

Description of Examples FIG. 1 is a side view of a battery structure 10 including a cathode 11 containing lithium, a separator 12 impregnated with an electrolyte, and an anode 13. Also, the current collectors 1 on both sides of the electrode
4, and also a surrounding structure 15, usually made of an inert, non-conductive material. Batteries can be constructed with well known technology and need not be described in detail.

The cells of the present invention can be constructed by well known conventional methods, in which an anode comprising a mixed metal oxide such as vanadium tungsten oxide or titanium niobium oxide as the active material is spaced from a suitable cathode, Both electrodes are in contact with each other via a conductive non-aqueous electrolyte. The electrolyte preferably does not react with both the anode and cathode materials. Suitable electrolytes are lithium hexafluoroarsenate or lithium perchlorate in propylene carbonate and lithium tetramethylboron in dioxalane. The current collector contacts both the anode and the cathode and can supply current to external circuitry (not shown).

Batteries can be manufactured charged or discharged. When manufactured in a charged state, a mixed metal oxide such as vanadium tungsten oxide can be manufactured as follows and used directly as an anode material. Lithium treatment (lith
An iated) mixed metal oxide such as vanadium tungsten oxide or niobium titanium oxide can be used as the anode material. The conductivity of the anode should be sufficient at all charge states to minimize dissipation losses. Generally, in order to obtain the desired conductivity of the mixed metal oxide anode, a conductive but chemically inert material such as graphite is added to the anode.

Other battery structures can be constructed, such as structures with thin film electrodes. Batteries with thin film electrodes can be assembled in several ways. For example, the various sheets forming the electrodes and separators can be placed together to form a rectangular battery, or wound together to form a cylinder.

The anode has a nominal atomic composition x ^{M A} O ₂ as an active electrode material.
Represented by yM ^B ₂ O ₅ .zM ^C O ₃ (wherein at least two of x, y and z are not zero, x + y + z = 1.0, and at least two kinds of metals are present). Includes metal oxides such as vanadium tungsten oxide and niobium titanium oxide. In a preferred embodiment, M
^A is at least one element selected from the IVB, VB and VIB groups of the Periodic Table, M ^B is at least one element selected from the group consisting of the VB and VIB groups of the Periodic Table, M ^C is at least one element selected from group VIB of the periodic table. IVB group means Ti,
Means Zr and Hf. Group VB means V, Nb and Ta. Group VIB means Cr, Mo and W. In a preferred embodiment, M ^A and M ^B are V
And M ^C is W. In another preferred embodiment, M
^B is Nb and M ^A is Ti. Of course, two or more kinds of oxides can exist as the active anode material.

The above formula, xM ^A O ₂ · yM ^B ₂ O ₅ · zM ^C O
By using ₃ , a composition with fractional atoms is obtained. Chemical compositions are usually described by integer or half-integer atoms. Therefore, most compositions are represented as compositions having an integer or half-integer atom.

Compounds within the included composition regions are provided with tunnels and voids suitable for lithium transport and coordination, respectively,
It has an open frame structure. These compounds contain a series of closely related shear structures lying between the limiting atomic compositions MO ₂ and MO ₃ . The active anode material comprises at least one mixed metal oxide, such as vanadium tungsten oxide or niobium titanium oxide, within the specified composition region. Increasing the oxygen content from 2 to 3 increases the number of sites available for lithium. However, if too much oxygen is included, there is not enough edge sharing between the octahedra for stability. In other words, as the oxygen content decreases from 3, the edge allocation between the octahedra becomes
Therefore, stability is increased. If necessary or desired, the conductivity of the anode can be increased by intimately mixing a conductive material such as graphite with the active anode material.

Several methods for producing the included vanadium tungsten oxide are well known to those skilled in the art and have been reported in the literature. For example, Revue de Chimie Mineral
e, 8, 391-422, 1971, or Journal of Solid State Chemistry, 4, 3.
See pages 57-361, 1972. These methods will be briefly described. In one method, a suitable mixture of V ₂ O ₅ and VO ₂ and / or V metal powders is mixed with WO ₃ and / or W metal in a sealed vacuum quartz tube,
React at a temperature below 00 ° C.

In the second _method, VO _2, V _{2 O 5} and WO ₃ powder were thoroughly mixed, in a boat made of platinum or alumina, is heated under vacuum. The layer obtained depends on the tungsten / vanadium ratio of the starting mixture and the processing temperature. For example, a mixture of 0.67VO ₂ and 0.33WO ₃ is added to 8
The compound WV ₂ O ₇ is formed by heating to 00 ° C.

The compound V ₂₊ δW _1- δO _7.5 can be most easily produced with the preferred (M) -Nb ₂ O ₅ structure (so-called “wadsley phase” structure) as follows. Thoroughly _{VO 2,} V 2 _{O 5} and WO ₃ were pulverized and weighed to a molar portion of the well mixed. The powder is then heated in a sealed quartz tube under vacuum at about 650 ° C. for about 16 hours, removed from the tube and pulverized. The reaction is completed after two such cycles or by heating for a longer period without intermediate milling. Following the same procedure, W _0.6 V _2.4 O
₇ can be most easily manufactured with its preferred construction. Compounds with metals in the highest oxidation state are generally easy to synthesize without encapsulation. For example, TiNb ₂ O ₇ , Ti ₂ Nb ₁₀ O ₂₉ and TiN
b ₂₄ O ₆₂ can be synthesized by heating in air to a temperature of 1200 to 1300 ° C. Here, TiNb ₂ O ₇ is a crystal composed of a titanium oxide and a niobium oxide, and a substance having an element ratio of Ti: Nb: O = 1: 2: 7 in the crystal is Ti ₂ Nb ₁₀ O ₂₉ Is also 2:10:29 and TiNb ₂₄ O ₆₂ is also 1:24:62.
Represents the substance. Similar mixed methods, which can be readily ascertained by one skilled in the art, can be used to produce other mixed metal oxides useful in the batteries of the invention.

Lithium treated vanadium tungsten oxide as well as other oxides useful in the batteries of the present invention can be prepared by treating these compounds with n-butyllithium in hexane. The X-ray powder diffraction patterns of these lithium treated compounds are similar to those of the non-lithium treated compounds, indicating that the mixed metal oxide structure was not severely deformed during the insertion reaction. This is evidenced by the crystal unit cell parameters obtained from these patterns. For example, V ₂ WO _7.5 and L
With respect to i _3.5 V ₂ WO _7.5 , the crystal unit cell has a square symmetry (square symmetry) and is similar.

V ₂ WO _7.5 : a ₀ = 19.50, c ₀ = 3.70 Li _3.5 V ₂ WO _7.5 : a ₀ = 20.16 (5), c ₀
= 4.059 (4) Compounds within the above range are considered preferable for use in non-aqueous batteries due to their crystal structure and chemical properties of the constituent cations. M ^A and M ^B are V, M
^The structure where ^C is W can be briefly described as follows. Structures having other structural cations can be similarly described.

The basic building block of this structure is a distorted MO ₆ octahedron with vanadium or tungsten atoms near the center and surrounded by 6 oxygen atoms. In the standard compound ReO ₃ with stoichiometry MO ₃ , the octahedra share only the corners with 6 adjacent octahedra. It was found that this structure was moderately open, and the lithium insertion reaction resulted in the stoichiometric formula Li ₂ ReO ₃ . However, this structure undergoes a severe twist at the corners of the octahedron, enclosing itself in the process. When the metal to oxygen ratio is greater than 1: 3, the octahedra can no longer share the corners exclusively and when the stoichiometry changes from MO ₃ to MO ₂ , the octahedrons share the edges. Increase in number. MO ₃ ~ M
Compounds within the stoichiometric range between O ₂ are a mixture of octahedrons that share corners and edges, and yet in their structure, generally extensive edge-sharing areas. Shows an open tunnel-like area in contact with. When a sufficient amount of edge sharing is introduced, the structure becomes lithium-inserted ReO ₃
It becomes stiff against torsional deformations such as those found in, and no longer surrounds itself. Therefore, the structure remains open upon insertion of lithium and does not interfere with the diffusion of lithium ions.

Compounds of the above type that fall within the stoichiometric range between MO _{2 and} MO ₃ are termed “Wadsley phases” and have a wide range of MO ₆ octahedra that share edges and corners. And the geometric structure is shown. "Wadsley Phase"
Characterized by a structure of blocks of MO ₆ octahedra that share the corners connected to adjacent blocks through the edge sharing or the combination of the edge sharing and the tetrahedrally coordinated metal atoms at the corners of the blocks Is. The block is infinite in one dimension, so this structure is nxmx∞R
n and m are believed to consist of eO ₃ type blocks.
Is the number of octahedra along the length and width of the block, respectively. Observation of a structure in which n and m were 2 to 5 revealed that some had two or more types of blocks. The Wadsley phase is, for example, a chemical system Nb ₂ O ₅ —WO ₃ , Nb _{2
O 5 -NbO 2, Nb 2 O} 5 -TiO 2, and Nb ₂
O ₅ -NbO occurs extensively ₂ F. Empty oxygen or fluorine positions are energetically unfavorable and small differences in the stoichiometry lead to different amounts of edge sharing, resulting in many similar but different crystal structures observed. . Further, even if the stoichiometric formula is the same, different layers may be formed due to the difference in chemical and / or synthesis conditions.

The compound of the Wadsley phase type has the formula M _{nmp + 1} O _{3nmp- (n + m) p + 4}
, Where n and m limit the size of the blocks and p is the number of blocks at one level connected by edge sharing. Compounds of different stoichiometry may also be present, depending on the mode of edge sharing.

To elaborate on the "Wadsley phase" in more detail, the "Wadsley phase" was named after one of the chemists and crystallists who discovered the principle of its formation in the 1960s and 1970s. "Wadsley phase" refers to a special structural and chemical class of transition metal oxides. The crystal structure of the "wadsley phase" is unique in that they consist of a large region of a three-dimensional open and permeable framework called the "block". Blocks are connected around them by densified atomic planes called "shear planes" that are very stable and resistant to bending, twisting or breaking. This unique "Wadsley phase" type crystal structure is particularly convenient for use in the secondary batteries (storage batteries) described herein. It is because the permeable block structure can accommodate a large percentage of Li in the open framework and the rigid shear plane around the block ensures that the crystalline structure is maintained even when Li is inserted into the open framework. It won't collapse.

It is practically always the oxygen atom that is closest to the metal atom in a ceramic material based on a compound composed of bound metal and oxygen atoms. The nearest oxygen atom forms an octahedron.

FIG. 9 shows this. If a plurality of metal-oxygen octahedra are connected to each other so that the corners of the octahedra are in contact with each other and the oxygen atoms at the corners are shared by the two octahedra, and then spread in the three-dimensional direction,
The crystal has a simple structure called ReO ₃ as shown in FIG. The blank space between the octahedra is a large void into which large Li atoms are inserted and forms the basis of the secondary battery. However, this crystal structure is not a rigid structure because each octahedron can rotate around a corner (vertex) shared by others and the voids are easily collapsed.

The "wadsley phase" is formed from metal-oxygen octahedra with metal atoms Nb, V, W and Ti. It is also possible to bond metal-oxygen octahedra of these atoms.
The basic construction block of the Waddsley phase does not spread infinitely in all three directions, but only in one of the three directions and a finite number in the other two directions. Is restricted to the octahedron of. These areas are called "blocks". Typical block dimensions are, for example, 3 octahedron widths and 4 octahedron captains or 3 octahedron widths and 5 octahedron lengths. These blocks contain large voids available for Li insertion as well as the structure of ReO ₃ . However, this block is concatenated with other blocks in a special way to fill the space in three dimensions. That is, each block is shifted parallel to the infinite length direction and the octahedra are linked so that their edges share two (but not one) oxygens with each other. Thus, the octahedra share edges (sides) with each other (as shown by the dotted lines in FIG. 9) rather than corners. Thus, depending on the dimensions of the ReO ₃ like blocks and the exact way they are shared, different crystalline structures are formed. A typical example of this is shown in Figures 11 and 12 (these figures are drawn from a vision overlooking the infinite block direction). The material thus formed is very stiff. That is, since the octahedrons share their edges, the rotation of the octahedron is extremely strongly restrained, so that the formed void does not collapse during Li insertion.

Finally, if we give a concise definition of the "Wadsley phase" material, it becomes as follows.

(i) Composition (or component) Typically, (a) Nb and O, (b) Nb, Ti and O, (c) Nb, W and O, (d) V, W, and O,
(E) A combination of Nb-O and F (F is a substitute for O). Specific examples include Nb ₂ O ₅ and Nb ₁₂ O ₂₉ shown in FIGS. 11 and 12. It should be noted that many other examples are known.

(ii) Structure For the crystal structure, refer to the above description and FIGS. 9 to 12.

(iii) Property It has the ability to insert Li without destroying the structure.

(iv) Production Method Although described in detail below in connection with the present invention, typically, Nb ₂
O ₅ , NbO ₂ , WO ₃ , WO ₂ , TiO ₂ , V ₂ O ₅
And simple oxides such as VO ₂ are mixed together and the mixture is heated at an elevated temperature.

Non-aqueous electrochemical cells using these compounds as the active anode and lithium as the active cathode had an open circuit cell voltage of 2.6-2.8 volts. The relationship between the battery voltage and the lithium content is shown in FIGS. 2 to 6 as the active anode material: WV ₂ O _7.5 , W _0.8 V _2.2 O _7.5 , W _0.6 V _2.4 O ₇ , WV
₂ O ₇ and WV ₂ O _7.3 were added to 10.15, 7.
Shown for cells having amounts of 65, 6.0, 7.1 and 7.9 mg. For the first, second, fourth and fifth cells, x is 0.34 to 0.4 and y is 0.2 to 0.
31 and z is 0.34 to 0.4. The second, third and fifth cells contained a mixture of phases. Here, the first cell, the second cell, the third cell, the fourth cell and the fifth cell
The cells are WV ₂ O _7.5 , W _0.8 V _2.2 O _7.5 , W _{0.6, respectively.}
Corresponds to V _2.4 O ₇ , WV ₂ O ₇ and WV ₂ O _7.3 .
These cells were cycled at 20 mA. The electrolyte was LiAsF ₆ in propylene carbonate and the anode contained 50% by weight of graphite in addition to the active material. No self-discharge was observed for several weeks. These x, y and z numbers limit the preferred range of values. However, these values are approximate.

The vanadium tungsten oxide in the composition provides a good combination of desirable structural and chemical properties. Although the niobium-containing compound is effective, vanadium is considered to be a preferable component from this viewpoint because it is more likely to be reduced when lithium is inserted. However, titanium-niobium compounds appear to be easy to process. The addition of tungsten to vanadium clearly stabilizes the wadley structure. For example, the compound V ₂₊ δW _1- δO _7.5 is 4 × 4
It can be synthesized with a wadsley phase structure of x∞ (M) -Nb ₂ O ₅ . It has been found to form certain compounds within the stoichiometric range in the tungsten-vanadium system 4
There are different types of chemical compositions. These compositions have V ₂₊ δ
W _1- δO _7.5 (x = 0.348-0.400, y = 0.
200-0.304, z = 0.348-0.400),
V _2.4 W _0.6 O ₇ (x = 0.615, y = 0.154, z
= 0.231), V ₂ WO _7.3 and V ₂ WO ₇ . Two different compounds are known to be formed with V ₂₊ δW _1- δO _7.5 depending on the temperature of synthesis. The preferred morphology for non-aqueous lithium electrochemical cells is formed at temperatures below 800 ° C. and has a (M) -Nb ₂ O ₅ , 4 × 4 × ∞ wadsley phase structure.

MO _{2.3 to} MO _{2.7, wherein} M is a mixture of metals selected from Groups IVB, VB and VIB of the Periodic Table, as described above.
Twelve structurally and / or chemically different Wadsley type phases within the range were prepared. A lithium-intercalated compound having the stoichiometric formula LiγMO _2.3-2.7 was chemically synthesized by treating the oxide with n-butyllithium in hexane. Γ value of 0.5 to 1.1 (MO
Value indicating the amount of lithium to be inner position added to Wadosurei type phase structure given in the range of oxygen _2.3-2.7) at room temperature was obtained. In all cases lithium could be removed by a chemical reaction with iodine in acetonitrile, leaving the original oxide phase unchanged. These results show that little edge sharing is needed to stabilize the structure against twisting due to lithium insertion. For example, the compound with the largest block size, 5x5x∞,
W ₈ Nb ₁₈ O ₆₉ , (MO _2.633 ), (x = 0.0, y =
0.529, z = 0.471) reversibly reacts with n-butyllithium to give a stoichiometric formula of Li ₂₂ W ₈ Nb ₁₈ O ₆₉ , γ
= 0.85.

As an active material, TiNb ₂₄ O ₆₂ (x = 0.0
77, y = 0.927, z = 0.0) 6.95 mg and Ti ₂ Nb ₁₀ O ₂₉ (x = 0.286, y = 0.714,
The relationship between battery voltage and lithium content is shown in FIGS. 7 and 8 for a battery containing 7.8 mg of z = 0.0). Further, as an active anode material, TiNb ₂ O ₁₀ (x = 0.5,
It had good properties with y = 0.5, z = 0.0). The electrolyte was lithium perchlorate in propylene carbonate and the anode contained 50% by weight of graphite in addition to the active material.

[Brief description of drawings]

FIG. 1 is a side view of a non-aqueous battery of the present invention having a cathode and an anode. FIG. 2 shows a battery with WV ₂ O _7.5 as the active anode,
It is a graph which shows the relationship between battery voltage and lithium content. FIG. 3 is a graph showing the relationship between battery voltage and lithium content of a battery having W _0.8 V _2.2 O _7.5 as an active anode. FIG. 4 is a graph showing the relationship between battery voltage and lithium content of a battery having W _0.6 V _2.4 O ₇ as an active anode. FIG. 5 is a graph showing the relationship between battery voltage and lithium content of a battery having WV ₂ O ₇ as an active anode. FIG. 6 shows a battery with WV ₂ O _7.3 as the active anode,
It is a graph which shows the relationship between battery voltage and lithium content. FIG. 7 is a graph showing the relationship between battery voltage and lithium content of a battery having Ti ₂ Nb ₁₀ O ₂₉ as an active anode. FIG. 8 is a graph showing the relationship between battery voltage and lithium content of a battery having TiNb ₂₄ O ₆₂ as an active anode. FIG. 9 is a diagram showing an octahedron formed by a metal atom and the nearest oxygen atom. FIG. 10 is a diagram showing the crystal structure of ReO ₃ . FIG. 11 is a diagram showing a crystal structure of Nb ₂ O ₅ . FIG. 12 is a diagram showing a crystal structure of Nb ₁₂ O ₂₉ . [Explanation of Signs of Main Parts] 11 ... Cathode (negative) 13 ... Anode (anode) 10 ... Non-aqueous secondary battery

Continuation of the front page (72) Inventor Donald Winslow Murphy-USA 07060 New York City Summer Set Warren Old Starling Road 29 (56) Reference References JP 54-108221 (JP, A) JP 55-12675 (JP, A)

Claims (11)

[Claims] 1. A non-aqueous secondary battery comprising an anode, an electrolytic solution, and a cathode, wherein the active material of the anode has an atomic composition formula: xM ^A O ₂ .yM.
The _{^{B 2 O 5 · zM C O}} 3 (M A, IVB of the CAS Periodic Table
At least one element selected from the group VB, the group VIB and the group VIB, M ^B , in the group VB and VI of the CAS periodic table
At least one element selected from Group B elements and M ^C as a tungsten element, and at least two of x, y, and z are values other than zero and satisfy x + y + z = 1.0. , The M ^A , M
^B and M ^C are represented by at least two different elements), and the cathode is lithium, and the electrolyte is a lithium salt. A non-aqueous secondary battery comprising a solution containing: 2. The non-aqueous secondary battery according to claim 1, wherein at least one of M ^A and M ^B is a VB group element. 3. The non-aqueous secondary battery according to claim 2, wherein the VB group element is V. 4. The battery according to claim 3, wherein x is in the range of about 0.3 to about 0.6. 5. The battery according to claim 4, wherein y is in the range of about 0.15 to about 0.31. 6. The non-aqueous secondary battery according to claim 5, wherein z is in the range of about 0.2 to about 0.4. 7. The battery of claim 3 wherein x is about 0.62, y is about 0.15 and z
Is about 0.23, a non-aqueous secondary battery. 8. A battery according to Patent paragraph 1 or claim 2, the non-aqueous secondary battery, wherein said M ^B element is Nb. 9. The non-aqueous secondary battery according to claim 8, wherein the M ^A element is Ti. 10. The non-aqueous secondary battery according to claim 9, wherein z is about 0.0. 11. The battery according to claim 10, wherein x is in the range of about 0.07 to about 0.50,
A non-aqueous secondary battery, wherein y is in the range of about 0.50 to about 0.93.