KR20030059177A - Vanadium Oxide Hydrate Compositions - Google Patents

Abstract

The present disclosure is a novel vanadium oxide hydrate composition and process for its preparation which is very suitable for use as electrode active material in primary and secondary lithium and lithium ion batteries.

Description

Vanadium Oxide Hydrate Compositions

Although well known in the art for a long time, vanadium oxide hydrate, represented generally by the formula V ₂ 0 ₅ nH ₂ O, has a large lithium ion insertion capacity, charge / discharge, which is required for practical use of rechargeable or "secondary" lithium batteries. The combination of low magnetic hysteresis phenomena, high power density, and low sensitivity to discharge rate in the cycle was generally not shown.

US Pat. No. 5,674,642 to Le et al. Discloses a fiber V ₂ 0 ₅ nH ₂ O composition having a sufficiently large lithium insertion capacity that can be selected as an electrode active material of a practical lithium battery. Similar fibres and ribbons are described in S. Passerini et al., Electrochimica Acta, Vol. 44,1999, pp. 2209-2217 and [J. Livage, Chem. Mater. Vol. 3,1991, pp. 578-593, according to the method of Les et al.

It is known in the art to combine electrode active materials with binder resins and carbon black to form electrode pastes or inks for use in batteries. Carbon black greatly improves the performance of the electrode material, resulting in a much higher percentage of its theoretical capacity at high charge and discharge. However, the literature of Leh et al. Discloses that the compound still exhibits significant losses in capacity and reversibility at high charge and discharge, and this problem is exacerbated at high speed.

In addition, although the amount of binder is constant, an electrode having a large ratio of carbon black to V ₂ 0 ₅ · nH ₂ O can be formed to improve the capacity to theoretical limits at high speed discharge and charging, but practical limitations on these ratios There is. Increasing the amount of carbon black without simultaneously increasing the amount of binder results in the loss of physical integrity of the formed electrode layer. This increases the binder, which dilutes the amount of electrode active material, greatly reducing the energy density of the resulting battery.

In addition, compositions of V ₂ 0 ₅ nH ₂ O having 4 to 7% by weight of chemically bound carbon solvent residues disclosed in the literature by Les et al. Increase the electrochemical potential of the battery, but the capacity and reversibility characteristics of the parent composition It is just enough to keep things.

Les et al. Disclose a gelling process for the preparation of V ₂ 0 ₅ · nH ₂ O, which is complex, slow and expensive. Advanced Inorganic Chemistry (4 ^th Edition, J. Wiley & Sons, Inc., 1980, p. 711) by Cotton and Wilkinson describes the precipitation of a brick-colored V ₂ 0 ₅ by adding an inorganic acid to an aqueous solution of vanadate. It describes how it was constructed. This method is also used in EP 747123A2, but the product obtained is described as having low yield, severe contamination and deviating properties. Similar methods are also described in Theobald, Bulletin de la Societe Chimique de France 1975, no. 7-8, pages 1607-1612, and similarly poor results were obtained.

Summary of the Invention

The invention of _{MxV 2 0 5 Ay · nH 2} 0 ( formula, M is ^{_{NH 4 +, Na +, K}} +, Rb +, Cs + , and is selected from the group consisting of Li ^+; A is NO ₃ ^-, SO and 0 <x <0.7, 0 < y <0.7 , and;; ^{- _4-Cl-2} and is selected from the group consisting of 0.1 <n <2 Im) to provide a method of manufacturing, the method is a water-soluble vanadate salt of Mixing with water to form a solution, and adding a strong inorganic acid to the solution such that the molar ratio of acid protons to vanadium is in the range of 0.70: 1 to 6: 1.

In addition, the present invention is selected from a fiber _{MxV 2 0 5 Ay · nH 2} 0 (wherein, M is a group consisting of NH ₄ ^+, Na ^+, K ^+, Rb ^+, Cs ^+, and Li ^+; A is NO ₃ ^-, SO ₄ ^-2 and Cl ^- is selected from the group consisting of: 0 and <x <0.7, 0 <y <0.7 , and; provide an electrode active material composition including a 0.1 <n <2 Im) and The method comprises the above electrode active material, characterized in that 0.1 <n <2.0 and the initial discharge capacity is between 315 and 400 mAh per gram of electrode active material composition.

Further provided is an electrode composition comprising the electrode active material composition of the present invention.

Finally, an electrochemical cell comprising an electrode composition comprising the electrode active material composition of the present invention is provided.

The present invention relates to novel vanadium oxide hydrate compositions and methods for their preparation which are very suitable for use as electrode active materials in primary and secondary lithium and lithium ion batteries.

1 shows a graph of the initial discharge capacity measured in Examples 1-16 as a function of H / V ratio.

2A and 2B show scanning electron micrographs of the nonfiber product of Example 10 at magnifications of 10,000 and 30,000, respectively.

3A and 3B show scanning electron micrographs of the nonfiber product of Example 16 at magnifications of 10,000 and 30,000, respectively.

4 and 5 show an initial discharge curve and a first recharge curve representing the kV-time versus voltage per gram of electrode active material measured in Examples 10 and 16, respectively.

The present invention provides a high purity non-fibrous form of V ₂ 0 ₅ nH ₂ O (wherein 0.1 <n <2), which is very suitable for use as electrode active material in batteries, in particular lithium and lithium ion primary batteries and secondary batteries. A method of forming and a composition, electrode and electrochemical cell formed therefrom. It has been found in the practice of the process of the invention that the V ₂ 0 ₅ nH ₂ O formed above typically exhibits certain contamination due to the residual cation of the vanadate salt used in the process of the invention and the residual anion of the strong acid. This residue does not affect the suitability of the V ₂ 0 ₅ nH ₂ O of the present invention for the intended use.

Since the residues are chemically incorporated into the product, the product of the method of the present invention are of the formula _{MxV 2 0 5 Ay · nH 2} 0 ( formula, M is NH ₄ ^+, Na ^+, K ^+, Rb ^+, Cs ⁺ and Li selected from the group consisting of ⁺ and; a is NO ₃ ^-, SO ₄ ^-2 and Cl ^- is selected from the group consisting of; and 0 <x <0.7, 0 < y <0.7 , and; to 0.1 <n <2 Im) It is more appropriate to indicate. Preferably, x and y are as close to zero as possible, but in practice about 0.2 is common.

For clarity and ease of use in the present invention, the term "V ₂ 0 ₅ nH ₂ O" refers to the product of the process of the invention comprising the full range of values of both x and y, i.e. 0 to 0.7. Used as a short form for betting.

In the process of the invention, the aqueous vanadate salt is dissolved in water, preferably with heating, and then the desired V ₂ 0 ₅ nH ₂ O product is precipitated in high yield. The product obtained exhibits a non-fiber form and is characterized by a surprisingly large initial discharge capacity in standard lithium batteries with very high reversibility.

For the purposes of the present invention, the term "initial discharge capacity" refers to the electrical discharge capacity of a standard lithium metal battery incorporating the V ₂ 0 ₅ nH ₂ O composition of the present invention as an electrode-active cathode material. The "initial discharge capacity" measured in a standard manner is believed to be a relative measure of the intrinsic lithium ion insertion capacity of the present V ₂ 0 ₅ nH ₂ O composition. For the purposes of the present invention, the initial discharge capacity is measured as follows: V ₂ 0 ₅ nH ₂ O of the present invention is combined with carbon black and binder resin in various embodiments described below to form electrode inks or pastes. . The electrode inks or pastes thus formed are combined in a standard lithium metal coin cell arrangement described below. The coin battery thus formed is in a charged state. The cell is then discharged in the range of 4 to 1.5 volts while measuring the voltage (V) and current (I) as a function of time. The measurement of the initial discharge capacity starts with a constant current discharge of 0.5 mA. When the voltage reaches 1.5 volts, the discharge mode is changed to a constant voltage, where the voltage remains constant but the current slowly decreases to one tenth of its initial value, or 0.05 mA. This constant voltage phase of the discharge, which causes the cell to almost equilibrate, has the effect of reducing the potential drop from the current, because the remaining cell polarization is in principle due to the transient potential required to insert lithium into the negative electrode material. The initial discharge capacity is the sum of charge transfers during the constant current phase and the constant voltage phase of discharge. To make this measurement, use a Marker Series 4000 tester (Maccor, Inc., Tulsa, Oklahoma) using a channel with a maximum current supply of 10 kHz and version 3.0 (SP1) software. It is known that it is suitable.

In the process of the invention, water, preferably deionized water, is mixed with the vanadate salt and the mixture thus formed is preferably stirred with heating to a temperature range of from 80 ° C. to below the boiling point of the mixture, preferably from 0.01 to 3 M, Preferably a solution having a vanadium concentration in the range of 0.1 to 1 M is formed. Suitable vanadate salts include ammonium, alkali and alkaline earth vanadates such as NH ₄ V0 ₃ , LiV0 ₃ , NaV0 ₃ , KV0 ₃ , RbV0 ₃ , CsV0 ₃ and MgV ₂ 0 ₆ . Preferably NH ₄ VO ₃ , LiV0 ₃ , KV0 ₃ , MgV ₂ O ₆ . Most preferably there are NH ₄ V0 ₃ , LiV0 ₃ and MgV ₂ O ₆ . Alternatively, V ₂ 0 ₅ is mixed with stoichiometric amounts of aqueous ammonium, alkali or alkaline earth hydroxides to form the corresponding vanadate solution in situ. Most preferably the solution is heated to its boiling point.

Preferably, a strong inorganic acid is added to provide a acid proton to vanadium ratio (referred to below as "H / V ratio") to the solution formed by heating and most preferably by boiling.

Acids suitable for the practice of the present invention include H ₂ SO ₄ , HNO ₃ , HCl or other strong acids, but exclude phosphorus containing acids which can form undesirable vanadium phosphate by-products. In addition, the vanadate salts of NH ₄ and Rb and preferably the vanadate salts of Na, K and Cs, typically have an acid / vanadium ratio of at least 1: 1 to avoid or minimize the simultaneous formation of M ₂ V ₆ 0 ₁₆ . Should be large enough. The acid may be incorporated in concentrated or diluted form, preferably in diluted form for safety.

After addition of the acid, the mixing should be continued for at least 1 minute, preferably at a temperature of at least 80 ° C., most preferably at boiling point, and may last for several hours. Typically, 5 to 60 minutes of mixing will be sufficient. The then immersed and the resulting V ₂ 0 ₅ · nH ₂ O precipitate out quietly along the supernatant, filtered, and obtained by any easy method, or the like to centrifugation V ₂ 0 ₅ · nH ₂ O precipitate Can be recovered. The precipitate is characterized by non-fibrous form and a contamination level of less than about 15%, typically less than about 4%.

In most cases it is possible to dissolve the vanadate salt in water at any easy temperature, including at room temperature, but in the practice of the present invention the rate of dissolution at room temperature is very slow, especially by heating to a temperature near or near the boiling point or boiling point. Increases significantly. At temperatures below the boiling point, agitation significantly increases dissolution.

The V ₂ 0 ₅ nH ₂ O precipitate of the present invention can be formed by addition of an acid to the vanadate salt solution at any easy temperature, including room temperature. However, it has been found that in the practice of the present invention it is very desirable to carry out the reaction at elevated temperatures, in particular in the range of from 80 ° C. to the boiling point of the solution. Most preferably, the reaction is carried out at the boiling point. In the practice of the present invention it has been found that the yield can be reduced and the quality or performance of the product can be reduced when the reaction is carried out at temperatures below 80 ° C.

Although not strictly required, it is highly desirable to recover the solids after collecting the recovered solids and slurrying them again in fresh water to remove contaminants. The number of washing steps required to achieve the desired level of purity will depend on the solubility of the impurities, the amount of water used, the level of desired purity and the efficiency of the slurrying method. In the practice of the present invention it has been found that it is sufficient to stop washing when the pH of the supernatant is about 2 or more for various purposes.

The recovered solid is then dried by any easy means, including but not limited to warming by radiation or heating in an oven. After drying, grinding and sieving, the thus produced V ₂ 0 ₅ nH ₂ O is prepared for incorporation into the electrode composition.

The resulting precipitate is V ₂ 0 ₅ nH ₂ O in the form of non-fibers with a high initial discharge capacity. The percent precipitation of dissolved vanadium, which primarily determines the yield of a single pass product, is mainly determined by the H / V ratio, with a high yield at an H / V ratio of about 1: 1 to 2: 1. The term "non-fiber" means that it has been confirmed by scanning electron microscopy at about 30,000 x magnification that it has a microstructure consisting of fibers or ribbons. 2A and 2B show scanning electron micrographs of the sample of Example 10 herein at 10,000 and 30,000 magnifications, and FIGS. 3A and 3B show scanning electron micrographs of the coated carbon sample of Example 16 herein.

The non-fiber V ₂ 0 ₅ nH ₂ O produced by the process of the invention is much higher than the V ₂ 0 ₅ nH ₂ O produced by the vanadium hydrochloric acid precipitation method which exceeds the H / V ratio limit of the process of the invention. It is characterized by a larger initial discharge capacity. This is shown in FIG. 1, where the initial discharge capacity is shown as a function of H / V ratio for the specific embodiments illustrated below. Of particular importance is the rapid increase and decrease of the initial discharge capacity at the upper and lower limits of the H / V ratio range suitable for the practice of the present invention. The optimum H / V ratio is achieved at an H / V ratio of about 1.5: 1 to 2.5: 1.

If the H / V ratio is exceeded, the product begins to deteriorate with reduced yield, increased contamination, and reduced initial discharge capacity. If it exceeds the range of 0.70 H / V 6, desired characteristics are hardly obtained.

The V ₂ 0 ₅ nH ₂ O of the present invention imparts high reversibility to the standard lithium test cells described herein. As much as 99% of the available capacity can be recovered by recharging. This is shown schematically in FIGS. 4 and 5, respectively, which shows each charge cycle which shows the reversibility of the discharge cycle after discharge associated with Examples 10 and 16 described below. As can be seen in the figure, low polarization was observed. Examples 10 and 16 show the same synthesis but with the difference that Example 16 includes a coated carbon composition and Example 10 is not included. The polarization of the coated carbon sample is low compared to the V ₂ 0 ₅ nH ₂ O sample of uncoated carbon, as indicated by the more adjacent access of the curve in the low voltage region. The beneficial effect of the coated carbon composition has become significantly more pronounced with increasing discharge and charge rates.

The cycle period is defined as the number of cycles of charge and discharge cycles in which a test coin cell can be performed before the discharge capacity decreases to 80% of its initial value. We have found that the cycle duration has an optimal value at an H / V ratio of about 4. This indicates that there may be some tradeoff between yield and initial discharge capacity on the one hand and yield and cycle duration on the other.

It has further been found in the practice of the present invention that the initial discharge capacity depends on the cation of the vanadium salt used in the process of the invention. The initial discharge capacity becomes maximum when V ₂ 0 ₅ nH ₂ O is generated from NH ₄ V0 ₃ , LiV0 ₃ or MgV ₂ O ₆ .

It will be appreciated by those skilled in the art that the requirements for a particular use of the present invention V ₂ 0 ₅ nH ₂ O are chosen differently to obtain the most suitable product for that use among the several variants described herein.

In one preferred embodiment of the process of the invention, elemental carbon, for example carbon black, is slurried in a vanadium salt solution and then acid is added. In the practice of the present invention, carbon black is added to the water prior to dissolving the vanadium salt in water, simultaneously with dissolving the vanadium salt or after dissolving the vanadium salt. The precipitate product obtained after the addition of an acid in the manner described above is a finely dispersed powder of carbon black coated with V ₂ 0 ₅ nH ₂ O which is highly preferred for use in secondary or rechargeable lithium batteries. The coated carbon black product exhibits a high initial discharge capacity characteristic of V ₂ 0 ₅ nH ₂ O with low polarization, high capacity retention at high discharges and high vanadium utility or energy efficiency. The amount of carbon black known to be suitable for carrying out the invention ranges from 1 to 12% by weight, preferably from 4 to 8% by weight of the total weight of the final isolated carbon-V ₂ 0 ₅ nH ₂ O dry powder. When n is a preferred value of about 1.2, 1 to 12% by weight corresponds to a carbon-vanadium molar ratio of 0.1 to 1.2.

Finely dispersed elemental carbon is suitable for carrying out the present invention in any form. Super P carbon black commercially available from MMM S. A. Carbon (Brussels, Belgium) is one of the suitable elemental carbons having a surface area of about 62 m 2 / g. There is no particular limitation on the surface area in determining the carbon black suitable for use in the present invention, but it is believed that a larger surface area is preferable to a smaller surface area. In one embodiment, carbon black is first slurried separately in an aqueous dispersion and the resulting slurry is added to a heated vanadate solution.

The process of the invention can be carried out both batchwise and continuously. Continuous processes using a recycle stream of unprecipitated vanadate salts are particularly preferred when the reaction is carried out under relatively low yield conditions.

In the process of the invention, it is desirable not only to reduce the values of x and y as close as possible to zero, but also to remove any other residual ionic contaminants such as adsorbed protons. This is accomplished by washing the product precipitated in water and then filtering.

Combining an electrode active material, such as V ₂ 0 ₅ nH ₂ O of the present invention with carbon black and binder resin, forms an electrode composition that provides improved physical conductivity as well as good physical integrity for the electrode composition. It is well known in the electrochemical cell manufacturing art. However, it has been found in practice that 8% by weight of carbon black exhibits a typical actual maximum carbon black concentration because an excess of 8% often undesirably results in an electrode composition that is difficult to process and brittle. The present invention solves the problem by incorporating additional elemental carbon into the composition having a minimal deleterious effect on the physical integrity of the electrode composition formed in accordance with the practice herein. For example, preferred electrode compositions of the present invention include a V ₂ 0 ₅ nH ₂ O coated carbon black composition incorporating 8% carbon black formed according to the method of the present invention as described above. Such compositions are combined with additional 8% carbon black and binder resins in accordance with the teachings of the present invention to provide robustness that includes 16% carbon black and has the improved electrochemical performance expected from the high total concentration of carbon black of the electrode composition. A moldable electrode composition is formed.

Suitable binder resins include EPDM rubber, polyvinylidene fluoride and copolymers thereof, such as hexafluoropropylene, as well as other resins known in the art to be suitable for this purpose. The binder resin is typically first dissolved in a fugitive solvent and then combined with other components of the electrode. Suitable solvents are well known in the art and in particular include acetone, cyclohexane and cyclopentanone. Not all binders suitable for the practice of the invention need to be dissolved in a solvent.

V ₂ 0 ₅ · The electrode compositions of this invention containing the elements carbon coated with _{nH 2 O, V 2 0 5} · nH 2 O is of the present invention is not coated on the element carbon V ₂ 0 ₅ · nH ₂ O It has been found in the practice of the present invention that it represents a significant advantage over similar electrode compositions comprising. These advantages include reduced polarization in the charge / discharge cycles, higher initial discharge capacity per gram of vanadium, and a much smaller decrease in initial discharge capacity at increasing discharge rates.

In the process for the production of carbon coated with V ₂ 0 ₅ nH ₂ O, addition or doping of other elements may also be used. For example, in the case of precipitation of V ₂ 0 ₅ nH ₂ O by addition of a transition metal or metal compound followed by acid addition, a chemically modified precipitation product is obtained after acid addition and is represented by the formula M _x B _z V ₂ O ₅ A _{y n} H ₂ O wherein M is a cation derived from the vanadate salt which precipitated V ₂ 0 ₅ nH ₂ O of the present invention, x = 0.0-0.7 and A is an acid-derived anion And y = 0.0 to 0.7, B is a transition metal, a main group metal or a rare earth metal, z = 0.0 to 1.0, and n = 0.1 to 2.0.

The invention is further described in the following specific embodiments. Those skilled in the art will appreciate that various modifications, substitutions and rearrangements are possible in the present invention without departing from the intent or essential characteristics of the present invention.

Most of the specific embodiments described below relate to the formation of standard electrochemical cells using the electrode compositions of the embodiments as cathodes for lithium metal anodes. Lithium-ion cells can also be formed according to the method of the present invention and are preferred for many applications.

Lithium-ion batteries are assembled in a charged state using a positive electrode material which already contains suitable circulating lithium or portions thereof. This can be accomplished during assembly of a cell that allows the essential circulating lithium to be contained in the carbon structure, for example by contacting a lithium metal or some other lithium source with a carbon based positive electrode material, as known in the art. Other means for using the claimed materials in lithium-ion batteries include planned prelithiation of vanadium oxide hydrate by, for example, chemical or electrochemical means. This, together with the initially discharged positive electrode, increases the lithium content of the material, which is preferably required at higher levels for use in lithium-ion batteries. An example of a lithium ion battery is provided in Example 17.

In Examples 1 to 16 below, after forming vanadium oxide hydrate, the electrode incorporated in the lithium battery was combined with other materials known in the art, and all the steps were achieved according to the method described below. As shown in FIG. 1, the lithium discharge capacity of the coin battery thus formed was measured and the results were plotted against the acid vanadium ratio used to form V ₂ 0 ₅ · nH ₂ O of the present invention.

Example 1

18.2 g of LiVO ₃ was added to about 450 ml of deionized H ₂ O while stirring with a Teflon coated magnetic stir bar in a 1 L Pyrex beaker. The contents of the beaker were heated to the boiling point to form a solution. While stirring, 7.5 ml of concentrated HNO ₃ was added to the boiling solution. The resulting solution was kept boiling while stirring for 5 minutes. H / V ratio was 0.7.

The beaker was then removed from heat and stirring continued for 3 hours 30 minutes at room temperature. The unwashed gelatinous precipitate was collected by filtration under reduced pressure. The product was filtered very slowly and the filtrate was orange indicating a significant amount of vanadium unprecipitated. The pH of the filtrate as measured by multi-color strip pH paper was about 3. The filter cake was dried overnight under an IR heating lamp to yield 7.4 g of material. _{(Li) 0.07 V 2 0 5} (N0 3) 0.07 · 0.9H ₂ 0 in the composition is derived by chemical and thermogravimetric analysis. Based on this composition, the calculated product yield was 42%. The X-ray powder diffraction pattern showed only the lines of V ₂ 0 ₅ nH ₂ O.

After grinding to produce a powder, the powder was sieved through a 200 mesh screen to obtain a powder suitable for making a cathode. To make the electrode, 1.5000 g of powder was combined with 0.1364 g of Super P carbon black commercially available from MMM SA Carbon (Brussels, Belgium) and 1.705 g of a 4 wt% solution of EPDM rubber in cyclohexane. 2.5 ml of cyclohexane was added to improve flow. The mixture was shaken with a mechanical shaker for 15 minutes in a glass vial with a cap to form a negative electrode paste.

The negative electrode paste was thinly applied to a Teflon® FEP sheet (E. I. du Pont de Nemours and Company, Wilmington DE) and stretched to form a film using a doctor blade having a gap of 15 mm. A dried film consisting of 88% by weight of powder, 4% by weight of binder and 8% by weight of carbon black was hot pressed with a calender roller between Kapton® polyimide sheet (DuPont) at 2000 psi and 110 ° C. An integrated electrode sheet suitable for use as a battery was formed. The thickness of the sheet was 115 탆.

The resulting integrated electrode sheet was used as negative electrode for Li metal positive electrode in electrochemical cell. The electrolyte solution provided LiPF ₆ in EC / DMC (ethylene carbonate / dimethyl carbonate). Glass fiber separators were used between the electrodes. The disks of the negative electrode, the positive electrode and the separator were cut with a punch. In a dry nitrogen atmosphere, the cathode and separator pieces are immersed in an electrolyte solution, stacked in a coin cell pan with Li and placed in a 2325 Coin Cell Crimper System manufactured by the National Research Council of Canada. Sealed under pressure). The coin cell was tested as described above and the initial discharge capacity was measured at 315 mAh / g.

Example 2

Dilute H ₂ prepared by combining 15.6 g of anhydrous V ₂ 0 ₅ and 7.2 g of LiOH-H ₂ O with 900 ml of deionized water and 3.6 ml of concentrated H ₂ SO ₄ with 40 ml of H ₂ O SO ₄ was added to the boiling solution and treated as in Example 1 except that heating was continued for 35 minutes after acid addition to form V ₂ 0 ₅ nH ₂ O. The H / V ratio was 0.75.

The beaker was then removed from heat and stirring was stopped. After 1 hour the unwashed and unwashed gelatin solids were collected by filtration under reduced pressure. The product was filtered very slowly and the filtrate was orange indicating a significant amount of vanadium unprecipitated. The pH of the filtrate as measured by multi-color strip pH paper was about 3. The filter cake was applied thinly to a large cover glass, dried at room temperature for 4 hours and dried under an IR heating lamp for 2 hours to give 12.5 g of dried powder. An impurity phase, thought to be Li ₂ SO ₄ H ₂ O, appeared in x-ray powder diffraction. Non-reactive impurities have the effect of diluting the active material and lowering the overall Li insertion capacity. The yield of the product was 65%.

The resulting dry powder of V ₂ 0 ₅ nH ₂ O was then processed and combined as described in Example 1 to incorporate 108 μm thick and 265 mAh of initial discharge capacity as incorporated in the coin cell as in Example 1 An electrode of / g was formed.

Example 3

The 18.2 g of LiV0 ₃ in combination with deionized water of 900 ml, and 15 minutes after the addition of a diluted H ₂ SO ₄ produced by combining a concentration of 4.8 ml H ₂ SO ₄ and H ₂ O in 20ml of boiling the solution and addition of acid Except that heating was continued for the same treatment as in Example 1 to form V ₂ 0 ₅ nH ₂ O. H / V ratio was 1.0.

The beaker was then removed from heat and stirring was stopped. The beaker was left to settle until it was cold to feel touched. About 400 ml of supernatant was decanted. The decanted supernatant was pale yellow, indicating that some non-precipitated vanadium was present.

About 400 ml of fresh H ₂ 0 was added to the precipitate of the beaker and then slurried by stirring with water for about 1 minute. The precipitate was left to settle for 10 minutes and the about supernatant of about 500 ml was decanted. About 500 ml of fresh H ₂ 0 was added and slurried for 1 minute. The precipitate was allowed to settle for about 20 minutes and the supernatant was decanted again.

The solid was collected on filter paper by vacuum filtration. The pH of the filtrate as measured by multi-color strip pH paper was about 3. The filter cake was applied thinly to a large cover glass and dried under an IR heating lamp to give 17.2 g of dried powder. _{(Li) 0.14 V 2 0 5} (S0 4) 0.07 · 1.1H ₂ 0 in the composition is derived by chemical and thermogravimetric analysis. Based on this composition, the calculated product yield was 97%. The X-ray powder diffraction pattern showed only the lines of V ₂ 0 ₅ nH ₂ O.

The resulting dry powder of V ₂ 0 ₅ nH ₂ O was then processed and combined as described in Example 1 to incorporate a coin cell as in Example 1 with a thickness of 115 μm and an initial discharge capacity of 355 mAh An electrode of / g was formed.

Example 4

50.0 g of anhydrous V ₂ 0 ₅ and 23.1 g of LiOH.H ₂ O are mixed with 350 ml of deionized water in 600 ml of Pyrex beaker, stirred with a Teflon coated magnetic stir bar and heated to about 80 ° C. to form a solution. I was. While stirring, 50 ml of concentrated HCl was added to the hot solution. H / V ratio was 1.1. After 15 minutes, heating and stirring were stopped and the slurry was cooled to room temperature.

The solid was collected on filter paper by dark filtration. The filter cake was dried overnight under an IR heating lamp, then reslurried with about 500 ml of fresh deionized water, collected again on the filter paper by reduced pressure and dried under IR heat. The composition of Li _0.2 V ₂ 0 ₅ Cl _0.2 .0.5H ₂ 0 was derived by thermogravimetric analysis, which is considered to be the following two step reaction.

_{Li 0.2 V 2 0 5 Cl 0.2} · 0.5H 2 0 → Li 0.2 V 2 0 5 + 0.5 H 2 0 + 0.1 Cl 2

The X-ray powder diffraction pattern showed only the lines of V ₂ 0 ₅ nH ₂ O.

Then dry powder of V ₂ 0 ₅ nH ₂ O produced as described in Example 1 except that the amounts of active material, EPDM binder and carbon black are 90%, 2% and 8% by weight, respectively. Processing and combining, as in Example 1, an electrode having a thickness of 90 mu m and an initial discharge capacity of 378 mAh / g was formed as in the coin cell.

Example 5

As in Example 1, except 20.1 g of NH ₄ VO ₃ was combined with 450 ml of deionized water, 15 ml of concentrated HNO ₃ was added to the boiling solution and heating was continued for 5 minutes after acid addition. Treatment formed V ₂ 0 ₅ nH ₂ O. H / V ratio was 1.4.

The beaker was then removed from the heat and stirring continued until the beaker felt cold to the touch. After collecting the solid on the filter paper by filtration under reduced pressure, the wet solid was slurried by stirring for 1 minute with a magnetic stir bar in 350 ml of fresh deionized water and then collected as above. The solid was slurried again in 350 ml portions of fresh water and collected as above. At this time, the pH of the filtrate was about 3. The filter cake was dried in air at 110 ° C. 15.4 g of product were obtained. _{(NH 4) 0.1 V 2 0} 5 (N0 3) 0.1 · 0.8H ₂ 0 in the composition is derived by thermogravimetric analysis. Based on the composition, the calculated product yield was 88%. The X-ray powder diffraction pattern showed only the lines of V ₂ 0 ₅ nH ₂ O.

The resulting dry powder of V ₂ 0 ₅ nH ₂ O was then processed and combined as described in Example 1, with a thickness of 125 μm and an initial discharge capacity of 367 mAh for incorporation into the coin cell as in Example 1 An electrode of / g was formed.

Example 6

18.2 g of LiV0 ₃ are combined with 450 ml of deionized water and treated as in Example 1 except that 15 ml of concentrated HN0 ₃ is carefully added to the boiling solution and heating is continued for 10 minutes after acid addition. To form V ₂ 0 ₅ nH ₂ O. H / V ratio was 1.4.

The beaker was then removed from heat and cooled to near room temperature. After collecting the solid on the filter paper by vacuum filtration, the wet solid was slurried by stirring for 1 minute with a magnetic stir bar in 400 ml of fresh deionized water and then collected as above. The pH of the filtrate as measured by multi-color strip pH paper was about 1. The filter cake was dried under an IR heating lamp to give 15.5 g of dried product. (Li) _0.05 V ₂ 0 ₅ (N0 ₃ ) A composition of _0.05 · 1H ₂ 0 was derived by chemical and thermogravimetric analysis. Based on the composition, the calculated product yield was 89%. The X-ray powder diffraction pattern showed only the lines of V ₂ 0 ₅ nH ₂ O.

The resulting dry powder of V ₂ 0 ₅ nH ₂ O was then processed and combined as described in Example 1, the thickness being incorporated into the coin cell as in Example 1 was 110 μm and the initial discharge capacity was 340 mAh An electrode of / g was formed.

Example 7

20.1 g of NH ₄ VO ₃ was combined with 900 ml of deionized water and treated as in Example 5 except heating was continued for 20 minutes after acid addition.

The beaker was then removed from heat and stirring was stopped. The solid was quickly settled and left for 5 minutes to settle. About 600 ml of supernatant was decanted. The decanted supernatant was pale yellow indicating some vanadium that was not precipitated. About 700 ml of fresh H ₂ 0 was added to the precipitate of the beaker and then stirred for about 1 minute to slurry with water. The precipitate was allowed to settle for 10 minutes to settle and drain about 700 ml of supernatant. About 700 ml of fresh H ₂ 0 was added and slurried for 1 minute. The precipitate was left for about 20 minutes to settle and the supernatant was decanted again. The pH of the supernatant was about 2. The product was collected on filter paper easily and quickly by vacuum filtration. The damp cake was crushed in a large cover glass and dried in air at room temperature for 3.5 days to yield 15.8 g of material. The bulky product was easily powdered in a mortar. _{(NH 4) 0.1 V 2 0} 5 (N0 3) 0.1 · 0.7H ₂ 0 in the composition is derived by thermogravimetric analysis. The X-ray powder diffraction pattern showed only the lines of V ₂ 0 ₅ nH ₂ O. Based on the composition, the calculated product yield was 91%.

The resulting V ₂ 0 ₅ nH ₂ O was then processed and combined as described in Example 1, with a thickness of 130 μm and an initial discharge capacity of 370 mAh / g as in Example 1 incorporated into the coin cell. An electrode was formed.

Example 8

8.2 g of NH ₄ V0 ₃ were combined with 150 ml of deionized water and treated as in Example 1 except that 6.6 ml of concentrated HN0 ₃ was added and heating was continued for 2 minutes after acid addition, H The / V ratio was 1.5.

The beaker was then removed from the heat and stirring continued until it was warm to feel tactile. The product was collected on filter paper easily and quickly by vacuum filtration. The unwashed cake was dried overnight under an infrared heating lamp.

A composition of (NH ₄ ) _0.1 V ₂ 0 ₅ (N0 ₃ ) _0.1 · 1H ₂ 0 was derived by thermogravimetric analysis. The X-ray powder diffraction pattern showed only the lines of V ₂ 0 ₅ nH ₂ O.

Then dry powder of V ₂ 0 ₅ nH ₂ O produced as described in Example 1 except that the amounts of active material, EPDM binder and carbon black are 90%, 2% and 8% by weight, respectively. Processing and combining, as in Example 1, an electrode having a thickness of 120 mu m and an initial discharge capacity of 383 mAh / g was formed as in the coin battery.

Example 9

V ₂ 0 ₅ nH ₂ O was prepared as in Example 3 using 18.3 g MgV ₂ 0 ₆ , except that a solution of 9.5 ml of concentrated H ₂ SO ₄ in 20 ml of deionized water was added. And the H / V ratio was 2.1.

Bikie was then removed from the heat and stirring was stopped. The solid was quickly settled and left for 5 minutes to settle. About 700 ml of supernatant was decanted. The decanted supernatant was pale yellow indicating some vanadium that was not precipitated. About 700 ml of fresh H ₂ O was added to the precipitate of the beaker and then slurried by stirring with water for about 1 minute. The precipitate was allowed to settle for 10 minutes to settle and drain about 700 ml of supernatant. The wash / removal step was repeated two more times. The pH of the supernatant at the last wash was between about 3 and 4. The product was collected on filter paper easily and quickly by vacuum filtration. The damp cake was crushed in a large cover glass and dried in air at room temperature for 2.5 days and then for 5 hours under an infrared heating lamp. 16.3 g were obtained. The product was easily powdered in a mortar. The calculated product yield was 96%. The X-ray powder diffraction pattern showed only the lines of V ₂ 0 ₅ nH ₂ O.

The resulting dry powder of V ₂ 0 ₅ nH ₂ O was then processed and combined as described in Example 1, with a thickness of 123 μm incorporating into the coin cell as in Example 1 and an initial discharge capacity of 365 mAh An electrode of / g was formed.

Example 10

20.1 g of NH ₄ VO ₃ were combined with 900 ml of deionized water, using a solution of 9.6 ml of concentrated H ₂ SO ₄ in 25 ml of deionized H ₂ O and heating continued for 20 minutes after acid addition. Except for the same treatment as in Example 1. H / V ratio was 2.

The beaker was then removed from heat and stirring was stopped. The solid quickly settled down. Washing was performed as described in Example 7. The pH of the final supernatant was about 2. The product was collected on filter paper easily and quickly by vacuum filtration. The wet cake was crushed in a large cover glass and dried by conventional means to yield 16.2 g of product. The bulky product was easily powdered in a mortar. _{(NH 4) 0.12 V 2 0} 5 (S0 4) 0.06 · 0.8H ₂ 0 in the composition is derived by chemical and thermogravimetric analysis. Based on the composition, the calculated product yield was 92%. The product was found to be non-fiber in SEM images of 30,000 × or less. The X-ray powder diffraction pattern showed only the lines of V ₂ 0 ₅ nH ₂ O.

The resulting dry powder of V ₂ 0 ₅ nH ₂ O was then processed and combined as described in Example 1 to incorporate a coin cell as in Example 1 with a thickness of 130 μm and an initial discharge capacity of 370 mAh An electrode of / g was formed.

Example 11

Example 10 was repeated except that a solution of 9.6 ml of concentrated H ₂ SO ₄ in 40 ml of deionized H ₂ 0 was used and heating was continued for 60 minutes after acid addition. H / V ratio was 2. 15.4 g of product was recovered.

_{(NH 4) 0.12 V 2 0} 5 (S0 4) 0.06 · 0.6H ₂ 0 in the composition is derived by thermogravimetric analysis. Based on the composition, the calculated product yield was 89%. The X-ray powder diffraction pattern showed only the lines of V ₂ 0 ₅ nH ₂ O.

The resulting dry powder of V ₂ 0 ₅ nH ₂ O was then processed and combined as described in Example 1 to incorporate a coin cell as in Example 1 with a thickness of 125 μm and an initial discharge capacity of 374 mAh An electrode of / g was formed.

Example 12

Example 7 was repeated except that 30 ml of concentrated HNO ₃ was added and the H / V ratio was 2.8. After washing and drying as in Example 7, 12.4 g of material was recovered. _{(NH 4) 0.09 V 2 0} 5 (N0 3) 0.09 · 0.5H ₂ 0 in the composition is derived by thermogravimetric analysis. Based on the composition, the calculated product yield was 73%. The X-ray powder diffraction pattern showed only the lines of V ₂ 0 ₅ nH ₂ O.

The resulting dry powder of V ₂ 0 ₅ nH ₂ O was then processed and combined as described in Example 1 to incorporate a coin cell as in Example 1 with a thickness of 115 μm and an initial discharge capacity of 350 mAh An electrode of / g was formed.

Example 13

Example 10 was repeated except that 19.2 ml of concentrated H ₂ SO ₄ in 40 ml of deionized H ₂ 0 was used. H / V ratio was 4. 13.6 g of product was recovered. A composition of (NH ₄ ) _0.12 V ₂ 0 ₅ (S0 ₄ ) _0.06 · 1H ₂ 0 was induced by thermogravimetric analysis. Based on the composition, the calculated product yield was 76%. The X-ray powder diffraction pattern showed only the lines of V ₂ 0 ₅ nH ₂ O.

The resulting dry powder of V ₂ 0 ₅ nH ₂ O was then processed and combined as described in Example 1, the thickness of which was incorporated into the coin cell as in Example 1 was 115 μm and the initial discharge capacity was 325 mAh An electrode of / g was formed.

Example 14

Example 3 was repeated except that 19.2 ml of concentrated H ₂ SO ₄ in 50 ml of deionized H ₂ 0 was added and heating continued for 20 minutes after acid addition. H / V ratio was 4. After washing and drying, 10.8 g of product were obtained. The calculated product yield was 62%. The X-ray powder diffraction pattern showed only the lines of V ₂ 0 ₅ nH ₂ O.

The resulting dry powder of V ₂ 0 ₅ nH ₂ O was then processed and combined as described in Example 1, the thickness of which was incorporated into the coin cell as in Example 1 with a thickness of 98 μm and an initial discharge capacity of 321 mAh An electrode of / g was formed.

Example 15

Example 10 was repeated except that 28.8 ml of concentrated H ₂ SO ₄ in 50 ml of deionized H ₂ 0 was used. H / V ratio was 6. 9.6 g of product were recovered. The calculated product yield was 55%. The X-ray powder diffraction pattern showed only the lines of V ₂ 0 ₅ nH ₂ O.

The resulting dry powder of V ₂ 0 ₅ nH ₂ O was then processed and combined as described in Example 1, with a thickness of 105 µm and an initial discharge capacity of 272 mAh for incorporation into the coin cell as in Example 1 An electrode of / g was formed.

Example 16

20.1 g of NH ₄ V0 ₃ was added to 900 ml of deionized H ₂ 0 while stirring with a Teflon coated magnetic stir bar in a 1 L Pyrex beaker. The contents of the beaker were heated to the boiling point to form a solution. 1.56 g of Super P carbon black commercially available from MMM SA Carbon (Brussels, Belgium) was slurried in 100 ml of deionized H ₂ 0 by shaking and the resulting slurry was stirred in a boiling solution. The amount of carbon black added was less than 8% by weight of carbon in the product.

While stirring, the vanadium-solution / carbon black mixture was reheated to the boiling point.

9.6 ml of concentrated H ₂ SO ₄ was diluted in 30-40 ml of deionized H ₂ O and the diluted acid was added to the boiling composition with stirring. H / V ratio was 2. The resulting mixture was boiled with stirring for 15 minutes.

The beaker was then removed from the heat and stirred for 1 hour. The solid was left to settle for 5 minutes. The warm supernatant was decanted.

The precipitate was reslurried in fresh H ₂ 0 for about 1 minute. The precipitate was left to rest for about 10 minutes to settle and the supernatant was decanted. A second aliquot of fresh water was added and the washing and solid separation procedures were repeated.

The washed and settled precipitate was collected on filter paper by vacuum filtration. The filter cake was cut into small pieces and dried in air for about 64 hours and then for 4 hours under an IR heating lamp. The X-ray powder diffraction pattern showed only the lines of V ₂ 0 ₅ nH ₂ O.

After grinding to produce a powder, the powder was sieved through a 200 mesh screen to obtain a powder suitable for making a cathode. It was found by SEM at 30,000 × magnification that the product was non-fiber.

Two electrodes were prepared using different binders. One electrode was prepared as described in Example 1, and as in Example 1, an electrode having a thickness of 120 mu m and an initial discharge capacity of 350 mAh / g was formed.

For another electrode, 1.0000 g of powder was combined with 0.1000 g of MMM Super P Carbon, 0.1539 g of Kynaflex (manufactured by Elf Atochem), 0.285 g of dibutylphthalate and 4.6 ml of acetone. . The mixture was shaken for 15 minutes with a mechanical shaker in a glass vial with a cap.

The negative electrode paste was thinly applied to a sheet of Teflon® FEP and stretched to form a film using a doctor blade having a gap of 10 mm. After evaporation of acetone, dibutylphthalate was extracted with dimethyl ether. A dried film consisting of 79.8% by weight active powder, 12.2% by weight binder and 8% by weight carbon black was hot pressed with calender rollers between Kapton® sheets at 2000 psi and 110 ° C. for use as a negative electrode in lithium batteries. A suitable integrated sheet was formed. The thickness of the sheet was 86 탆.

The disk of the negative electrode sheet was cut with a punch and incorporated into a coin cell as described in Example 1. Initial discharge capacity was 357 mAh / g.

Example 17

The electrode of Example 16 was used as negative electrode in Li-ion electrochemical cell. The anode consisted of lithium oxide graphite formed in a coin cell by reacting a thin disk of Li metal and graphite (graphite) at room temperature.

6.0000 g of graphite powder MCMB25-28 (Osaka Gas Company, Japan) was charged with 0.1936 g of Super P carbon black (MMM SA carbon, Brussels, Belgium) and 6.452 g of a solution of 4% by weight of EPDM rubber in cyclohexane. Combined. 2.0 ml of excess cyclohexane was added to improve flow. The mixture was shaken with a mechanical shaker for 15 minutes in a capped glass vial to form a graphite paste.

The graphite paste was thinly applied and stretched on a Teflon® FEP sheet (E. I. du Pont de Nemours and Company, Wilmington DE) to form a film using a doctor blade with a gap of 40 mm. Electrode sheet integrated by hot pressing with a calender roller between Kapton® polyimide sheet (DuPont) at 2000 psi and 110 ° C. after drying, a film of 93% graphite, 4% binder and 3% carbon black by weight Was formed. The thickness of the sheet was about 295 μm.

The disc, graphite, Li metal and fiberglass separator of the negative electrode were cut with a punch, which was cut in a glove box in a dry nitrogen atmosphere. In the glove box, the negative and separator pieces are immersed in an electrolyte solution consisting of LiPF ₆ in EC / DMC (ethylene carbonate / dimethyl carbonate), then stacked together with two graphite disks and one Li disk, and coin Li discs having a thickness of about 100 μm in the cell pan were sealed under pressure using a 2325 coin cell crimper system manufactured by National Research Council, Canada.

The coin cell was left for 90 hours before testing. Quantification of graphite and Li metal provides a lithium-graphite composition of LiCl _{10 with} little Li metal remaining in the coin cell prior to testing. The coin cell was tested according to the standard method used herein except that the voltage range was adjusted from 1.5 to 4.0 volts to 1.4 to 3.9 volts because the voltage of the lithium-graphite anode against Li metal was observed at about 0.09 volts. . Under the non-optimized coin cell assembly, an initial discharge capacity of 92% obtained in Example 16 was obtained in the Li-ion battery of this example.

Example 18

Example 10 was repeated except that the heated solution was cooled to room temperature before the acid was added.

After 10 minutes, only a small amount of solids formed. More solids were observed after 1 hour and more solids were formed after stirring overnight. The supernatant was found to contain vanadium that was soluble and not precipitated. The supernatant was decanted and the solid was slurried with stirring for 1 min with fresh deionized water. The precipitate was left to settle for about 10 minutes. The pH of the upper wash was measured with multi-color strip pH paper. The washed and settled precipitate was collected on filter paper by vacuum filtration. The filter cake was cut into small pieces and dried in the air overnight. 14 g were obtained.

Formation of the desired product was confirmed by X-ray powder diffraction. A composition of (NH ₄ ) _0.14 V ₂ 0 ₅ (S0 ₄ ) _0.07 · 1.1H ₂ 0 was derived by thermogravimetric analysis. Based on the composition, the calculated product yield was 77%. The X-ray powder diffraction pattern showed only the lines of V ₂ 0 ₅ nH ₂ O.

The resulting dry powder of V ₂ 0 ₅ nH ₂ O was then processed and combined as described in Example 1 to incorporate 120 μm thick lithium with a capacity of 330 mAh / h as incorporated in Example 1 An electrode of g was formed.

Example 19

20.1 g of NH ₄ VO ₃ was added to about 900 ml of deionized H ₂ O with stirring with a Teflon coated magnetic stirring in a 1 L pyrex beaker. After the contents of the beaker were heated to the boiling point to form a solution, the solution was cooled to room temperature. While stirring, 19.2 ml of concentrated H ₂ SO ₄ diluted in 50 ml of H ₂ 0 was added to the solution. The acid proton / vanadium ratio was 4. After 4 hours, only trace solids were formed.

Example 20

Example 10 was repeated except that the temperature of the solution was lowered to 45 ° C. before the acid was added.

The reaction was left overnight at 45 ° C. The acid proton / vanadium ratio was two. The supernatant was found to contain some vanadium that was soluble and did not precipitate. The supernatant was decanted and the solid was slurried by stirring with fresh deionized water for about 1 minute. The precipitate was left to settle for about 10 minutes. The pH of the supernatant as measured by multi-color strip pH paper was 2-3. The washed and settled precipitate was collected on filter paper by vacuum filtration. The filter cake was cut into small pieces and dried in air to yield 15.8 g of product.

X-ray powder diffraction showed a product consisting primarily of (NH ₄ ) ₂ V ₆ O ₁₆ with mainly the desired material. The calculated yield of V ₂ 0 ₅ nH ₂ O, where the (NH ₄ ) ₂ V ₆ 0 ₁₆ impurity was thought to be 10%, was 75 to 80%.

The resulting mixed phase dry powder was then processed and combined as described in Example 1, incorporating into the coin cell as in Example 1 according to the method described above with a thickness of 120 μm and a lithium capacity of 329 mAh / g. An electrode was formed.

Claims (13)

The vanadate salt is mixed with water to form a solution, and to the solution is added MxV ₂ 0 ₅ Ay.nH comprising adding a strong inorganic acid so that the molar ratio of acid protons to vanadium is in the range of 0.70: 1 to 6: 1. ₂ 0 (wherein M is selected from the group consisting of NH ₄ ⁺ , Na ⁺ , K ⁺ , Rb ⁺ , Cs ⁺ and Li ⁺ ; A is selected from the group consisting of NO ₃ ⁻ , SO ₄ ⁻² and Cl ⁻ ) Selected from 0 <x <0.7, 0 <y <0.7; 0.1 <n <2. The method of claim 1, further comprising heating the solution to a temperature in the range of from 80 ° C. to the boiling point of the solution before adding the strong inorganic acid. The method of claim 1, further comprising dispersing elemental carbon in the solution prior to adding the acid. The method of claim 1 wherein the molar ratio is in the range of from 1: 1 to 4: 1. The method of claim 1 wherein the concentration of vanadate salt in the solution is in the range of 0.1 to 1 mole. The method of claim 3 wherein the concentration of the carbon and the carbon in the final product MxV ₂ 0 ₅ · Ay method of 1 to 12% by weight of the total weight of nH ₂ 0. The method of claim 3 wherein the concentration of the carbon of the carbon in the final product and MxV ₂ 0 ₅ Ay · nH ₂ The method of 4 to 8% by weight of the weight of zero. A fiber _{MxV 2 0 5 Ay · nH 2} 0 ( In the formula, M is ^{_{NH 4 +, Na +, K}} +, Rb +, selected from the group consisting of Cs ^+, and Li ^+, and; A is NO ₃ ^-, SO ₄ ² and Cl ^- is selected from the group consisting of; 0 <x <0.7 and, 0.1 <n <2.0 Im) with the initial discharge capacity and the composition, characterized in that 315 to 400 ㎃h / g a. 10. The method of claim 8, wherein the composition further comprises a carbon and a carbon element of MxV ₂ 0 ₅ Ay · 1 to 12% by weight of the total weight of the coating in nH ₂ 0 on carbon. The method of claim 9, wherein the carbon and MxV ₂ 0 ₅ Ay · nH ₂ of 4 to 8% by weight of the weight of the composition containing the element carbon zero. An electrode comprising the composition of any one of claims 8, 9 or 10. An electrochemical cell comprising the electrode of claim 11. 13. The electrochemical cell of claim 12 in the form of a lithium or lithium-ion cell.