Schlossplatz 2, 48149 Minister, Germany

Surface modified lithium-rich oxides

The present invention relates to the technical field of lithium ion-batteries, and particularly relates to an electrode material for lithium-ion batteries, and a method for preparing the electrode material. Among energy storage devices, lithium ion batteries today are commonly used in portable consumer electronics due to their advantages of high energy density, long cycle life, and environmental friendliness. The growing demands of large-scale power sources, hybrid electric vehicles and energy storage devices for grid power systems currently impose challenging requirements on the performance of lithium-ion batteries. Particularly the limited capacity as well as the limited energy density of the cathode material have become a bottleneck and restrict the development and new applications of lithium ion batteries. Thus, the development of cathode materials with larger capacities or higher operating voltages has become a key factor for further enhancing the energy density of lithium-ion batteries. The state of art materials commonly used as cathode material includes lithium cobalt oxide (LiCo0 ₂ ), lithium manganese oxide (LiMn ₂ 0 ₄ ), lithium iron phosphate (LiFeP0 ₄ ), and nickel cobalt manganese oxide (LiNii/3Coi/3Mni/30 ₂ ). However, the specific capacities of these materials are mostly below 160 mAh g ^"1 , which is less than half of the capacity of graphite negative material. Recently lithium-rich oxides have been put forward as cathode material due to an available capacity of more than 250 mAh g ^"1 . Using such materials, a matching of anode and cathode UD 40758 / SAM:AL material becomes feasible. Lithium-rich layered oxides have a general formula LiM0 ₂ , where M is one or a combination of Mn, Ni and Co. Lithium-rich oxide has a layered structure similar to that of LiM0 ₂ wherein M is one or a combination of Co, Mn, Ni, but contain more Li ⁺ ions in the metal layers. The structure of lithium-rich oxides has been described as solid solutions or nanocomposites of layered Li ₂ Mn0 ₃ with one or more of layered LiM0 ₂ and spinel LiM ₂ 0 ₄ , particularly as a nanocomposite of LiM0 ₂ -like and Li ₂ Mn03-like phases.

The lithium-rich oxides however face several challenges including low capacity retention, poor rate capability and continuous fading of voltage during cycling, thus hindering wide spread commercial application. It is generally believed that the morphology of the material is an important factor that affects the electrochemical performance. Particularly surface modification or coating is used as an approach to improve the performance of the Li-rich materials. Coating materials such as metal oxide A1 ₂ 0 ₃ , metal fluoride A1F ₃ and conductive carbon have been applied. CN 102694164 B discloses a nitrogen or carbon modified surface, which was prepared by introducing a Li-rich material into a nitrogen or carbon-containing gas. The coating layer thus was obtained through post thermal treatment on the prior synthesized Li-rich materials. Post treatment however makes the synthesis approach more complex, and increases the material costs. Post treatment also leads to the degradation of active material.

It was an object of the present invention, to provide a lithium-rich oxide material that is suitable for use as electrode material with enhanced specific capacity and cycling stability in a lithium ion battery.

This object is achieved by a lithium metal oxide represented by formula (I) as follows:

Lii _+x Mn _y Mi_ _x _ _y 0 ₂ (I)

wherein: 0 < x < 0.33 and 0 < y < 1, and M is one or more metal selected from the group consisting of Al, Ni, Co, Cr, Ca, Zr, Nb, Mo, Sr, Sb, V, Ti and Fe, wherein the lithium metal oxide is surface modified with carbonaceous compounds.

It has been surprisingly found that the lithium metal oxide surface modified with

carbonaceous compounds provides for an electrode material distinguished by a significantly increased specific capacity and superior cycling stability. It could be shown that porous lithium-rich Li ₁ . ₂ Mno. ₅₆ Nio.i ₆ Coo.08O2 surface modified with carbonaceous compounds according to the invention provided a discharge capacity around 150 mAh/g under 2 C which was maintained for more than 500 cycles when used as cathode material. These properties considereably improve the electrochemical performance and may enable a use in large-scale power sources.

The term lithium metal oxide "surface modified with carbonaceous compounds" in the sense of the present invention identifies a lithium metal oxide containing carbon on the surface which may be present at the elemental state and/or in form of organic carbonaceous compounds or substance. Using X-ray photoelectron spectroscopy the carbonaceous compound in an embodiment was found to be a composition with one or more of C-C, C-0 and 0-C=0 bonds. Particularly sp C-C and amorphous C-C bonds were detected. It is assumed that layered or surface-modified organic or lithium-poor semi alkyl carbonates such as ROCO2L1, ROCO2R' or a polymeric-type ROC0 ₂ R' with R and R' being alkyl groups were formed on the surface of the lithium-rich material. Surface modification with carbon and/or carbonaceous compounds may be achieved and controlled by calcining the metal oxide with carbon-containing compounds. The lithium metal oxide surface modified with carbonaceous compounds in embodiments may be surface modified with carbon. The carbon content may be determined by known methods such as CHN elemental analysis, as shown in the experimental part. The amount of carbonaceous compounds, preferably of carbon, based on the total weight of the lithium metal oxide surface modified with

carbonaceous compounds, is in the range from > 0.001 wt% to < 10 wt%, preferably in the range from > 0.001 wt% to < 5 wt%, more preferably the range from > 0.01 wt% to < 2 wt%. The weight ratio of lithium metal oxide to carbonaceous compounds, preferably to carbon, may be in a range from > 9 : 1 to < 10 ⁴ : 1. The lithium metal oxide Lii _+x Mn _y Mi_ _x _ _y 0 ₂ is a lithium-rich oxide. The structure of the lithium-rich oxide may be described as solid solutions or nanocomposites of layered Li ₂ Mn03 with one or more of layered LiM0 ₂ and spinel L1M ₂ O ₄ . In preferred embodiments, the metal M is one or two transition metal selected from Ni and Co. In preferred embodiments, the lithium metal oxide is a lithium nickel manganese cobalt oxide represented by formula (II): xLi ₂ Mn03'yLiM02'zLiM ₂ 04 wherein 0<x<l , 0<y<l , 0<z<l , x+y+z=l , M= Ni _a Co _b Co _c , and a+b+c<l . A most preferred lithium-rich oxide is Lii. ₂ Mno.56Nio.i6Coo.o80 ₂ .

In preferred embodiments, the lithium metal oxide is a porous oxide. The present invention preferably provides porous lithium-rich layered oxides with a surface modified by

carbonaceous compounds. Among various morphologies, porous structure is preferred because the structure has a larger surface area, which could provide more electrode/electrolyte interface to benefit the lithium ions intercalation/deintercalation and the transfer of electrons. The electrode material thus provides much better electrochemical performance. The porous lithium metal oxide can have a desorption average pore diameter in a range from > 1 nm to < 500 nm, preferably in a range from > 3 nm to < 300 nm, more preferably in a range from > 5 nm to < 200 nm The desorption average pore diameter is calculable according to Barrett- Joyner-Halenda (BJH) analysis. The term "average" pore diameter refers to the average value of all pore diameter or arithmetically averaged pore diameter relative to all pores of the respective material. The pore diameter can for example be evaluated by using field-emission scanning electron microscopy. The porous materials produced by the method of the invention hence may have pores larger than 500 nm and pores smaller than 1 nm. The lithium metal oxide in preferred embodiments has a BET surface area in the range from > 0.5 m /g to < 50 2 2 2

m /g, more preferably in the range from > 1 m /g to < 30 m /g, more preferably in the range from > 2 m 2 /g to < 20 m 2 /g.

In preferred embodiments, the lithium metal oxide provides a porous structure and a carbonaceous compound-modified surface. The lithium metal oxide is usable as an electrode material for lithium ion batteries. Advantageously, on one hand, the primary particles of the lithium rich material may form a homogenous porous shape with large free vacation in between, instead of strongly agglomerated particles. On the other hand, each particle is surface modified by carbonaceous compounds which advantageously act as both as conductive layer and as protective layer. The electrode material thus is insulated from the electrolyte instead of being directly contacted. Therefore, the lithium metal oxide provided has a larger surface area which is well protected by the surface layer and provides improved electrochemical performance. A further aspect of the invention relates to a method for preparing a lithium metal oxide represented by the formula Lii _+x Mn _y Mi_ _x _ _y 0 ₂ (I), wherein: 0 < x < 0.33 and 0 < y < 1, and M is one or more metal selected from the group consisting of Al, Ni, Co, Cr, Ca, Zr, Nb, Mo, Sr, Sb, V, Ti and Fe, and wherein the lithium metal oxide is surface modified with carbonaceous compounds,

the method comprising the following steps:

a) mixing stoichiometric amounts of a manganese salt and one or more metal salt with a template in a solvent to form a solution;

b) mixing a lithium salt and an alkaline compound in water to obtain an alkaline solution; c) mixing the solution obtained from step a) and the alkaline solution obtained from the step b), thereby forming a precursor suspension;

d) drying the precursor suspension obtained from step c); and

e) calcining the dried precursor obtained from step d) to form the lithium metal oxide surface modified with carbonaceous compounds. The term "stoichiometric amount" in the sense of the present invention refers to the amount of the mangenese salt, metal salt and lithium salt required in each case, in accordance with the ratio of the equivalent weights, for producing the respective Lii _+x Mn _y Mi_ _x _ _y oxide. To produce L1MO ₂ , accordingly, 1 mol of a lithium salt and 1 mol of a metal salt are used.

The term "calcination" as used herein refers to the heating of a material in the presence of oxygen such as in air to create a condition of thermal decomposition. Calcining for example converts a metal hydroxide to a respective metal oxide.

The manganese and the metal in step a) are provided in the form of a salt. The term "salt" as used herein refers to a metal compound wherein the metal is provided in cationic form together with an anionic counter compound. The manganese salt, the metal salt and the lithium salt may be an inorganic metal salt or an organic metal salt. In preferred

embodiments, the salt is selected from the group consisting of a sulphate, acetate, carbonate, nitrate, chloride, oxalate, and mixtures thereof.

The solvent in step a) may be deionized water or a mixture of water and alcohol. Preferably the solvent in the step a) is a mixture of water and alcohol. The alcohol preferably is selected from the group consisting of methanol, ethanol, glycol, acetone and mixtures thereof. The solution formed in step a) preferably is an aqueous solution. An aqueous solution

advantageously supports the formation of metal hydroxides. The manganese and further metal salt or salts may be mixed with the template in a mixture of water and alcohol. In alternative embodiments, the metal salts may be solved in water and the template may be solved in alcohol and these may be mixed to form the solution in step a). In preferred embodiments, the volume ratio of deionized water to alcohol is in a range from > 0.1 : 100 to < 1000 : 1, preferably a range from > 1 : 9 to < 9 : 1. The method provides for lithium transition metal oxides prepared by a template method using a template, which is at least partially removed by post calcination. The method

advantageously may provide for a porous structured metal oxide having a larger surface area compared to other structures and thus providing more electrode/electrolyte interface to benefit the lithium ions intercalation/deintercalation reactions and the transfer of electrons. In preferred embodiments, the template in the step a) is selected from the group consisting of melamine-formaldehyde, polyethyleneglycol, carbon nanotube, polycarbonate and

polystyrene. A preferred template is an organic template. Poly(ethylene glycol) (PEG), a synthetic polyether that is readily available in a range of molecular weights, preferably has a Mw < 100,000. These polymers are amphiphilic and soluble in water as well as in many organic solvents such as alcohols. Low molecular weight (Mw <1,000) polyethyleneglycol are also preferred being viscous and colorless liquids. A preferred template is polystyrene (PS). Polystyrene according to IUPAC is denoted poly(l-phenylethene), and the chemical formula is (C ₈ Hg) _n , wherein preferably 330 < n < 3850. Polystyrene is commercially available. Polystyrene may be solid or foamed. Preferably polystyrene dispersed in solution may be used as template. In preferred embodiments, a nano-sized spherical polystyrene dispersed in solution is used as template. Polystyrene dispersed in solution may be synthezied by emulsion polymerization using potassium persulfate as an initiator and sodium dodecyl sulfate (SDS) as a surfactant a mixture of water and ethanol to which styrene monomer is added. The use of these templates and particular of polystyrene is preferred because it mixes with each metal ion at a molecular level and is soluble in water which is a common solvent used for dissolving a metal salt and mixtures o water and alcohol. Also preferred as template is carbon nanotube. Carbon nanotube in in the sense of the present invention identifies cylindrical carbon molecules, constructed by single-walled nanotube or multi-walled nanotube. The diameters preferably range from < lnm up to 50 nm. The length-to-diameter ratio preferably ranges up to 132000000: 1. Carbon nanotube also is considered as a preferred template due to its mass production, its capability to limit particle grow and advantageous guiding for specific crystal growth. In embodiments, the concentration of the template, particularly of polystyrene, in the solution of step a) is in a range from > 0.001 g/mL to < 2 g/mL, preferably in a range from > 0.002 g/mL to < 1 g/mL, more preferably in a range from > 0.005 g/mL to < 0.5 g/mL. The concentration of polystyrene as template in the solution of step a) may be about 0.02 g/ml. Increasing the amount of template provides a higher porosity. However, the desired high valence state of the transition metal ion could be also reduced. It was fond that in this range an advantegous balance between porosity and carbon content of the yielded oxide can be achieved which provides for good electrochemical performance. It has been found that if the concentration of the template is higher than 2 g/mL, in high carbon atmosphere a part of the manganese will be reduced under high temperature, leading to a generation of an impurity phase. The impurity in the resulting Li-rich material will impair the electrochemical performance when the material is used as active material in an electrode, and especially will impair the specific capacity of a cell.

Mixing of the metal salt and the template may include agitating the mixture to form a solution, a dispersion or an emulsion. A solution may be formed or a dispersion. As used herein the term solution also includes a dispersion. Preferably the mixing may be supported by stirring. Further, the mixing may be supported by heating the solution. The solution may be heated to a temperature in a range of > 40 °C to < 150 °C, preferably in a range of > 45 °C to < 120 °C, more preferably to temperatures in the range of > 50 °C to < 100 °C.

In embodiments, in step b) the Li salt is selected from the group consisting of LiOH, L1NO ₃ , LiCl, Li ₂ Ac and mixtures thereof. The lithium salt is provided in a stoichiometric amount in regard of the mangenese salt and/or the metal salt or salts as required for producing the respective Lii _+x Mn _y Mi_ _x _ _y oxide. In a preferred embodiments, in step c) the mole ratio of alkaline substance to the lithium salt is in a range from > 1 : 0.5 to < 1 : 50, preferably in a range from > 1 : 1 to < 1 : 5. The term "mole ratio" or "molar ratio" as used herein refers to the ratio between the amounts in moles of any two compounds involved in a chemical reaction. It was found that if the amount of Li salt is that high, it may form a salt flux, such as a LiCl flux for example, at high temperature during the annealing process. Reactions in flux facilitate advantageously the particle mixing compared to solid-state reactions.

In embodiments, the alkaline compound is selected from the group consisting of NH ₄ OH, NH ₄ HCO ₃ , (NH ₄ ) ₂ C03 and mixtures thereof. It was found that these alkaline compounds provide the advantage of supporting that a majority of the transition metal ions are precipitated, while on the other hand, no impurity element such as Na ⁺ if using NaOH will remain after the annealing.

In preferred embodiments, in step c) the solution from step a) is added to the alkaline solution from the step b), thereby forming a precursor suspension. It is assumed that in step c) transition metal hydroxides precipitate on the template. The forming of the precursor suspension may be supported by stirring and/or heating. In preferred embodiments, the precursor suspension is heated to a temperature in a range of > 30 °C to < 150°C. Preferably the precursor suspension is heated to a temperature in the range of > 45 °C to < 120 °C, more preferably in the range of > 60 °C to < 80 °C. Particularly temperatures of 60 to 80 °C have been found to support the interaction between the template and the metal hydroxide species and provide for a homogeneous precursor. According to the reaction temperature the precursor solution may be allowed to react for shorter or longer periods. In preferred embodiments, the precursor solution is reacted for a time period in a range of > 10 minutes to < 100 hours, preferably in the range of > 2 hours to < 10 hours, more preferably in the range of > 6 hours to < 8 hours. Such time ranges have been shown to provide for a good precursor formation.

Heating may be performed in air or in another gaseous atmosphere such as under nitrogen or argon. The atmosphere will influence the crystal particle grow. It was found that by heating under inert gas particles having a smaller size could be obtained. The reaction preferably is performed in inert gas atmosphere. The inert gas preferably is one or more selected from the group consisting of N ₂ and Ar.

The concentration of the template, particularly of polystyrene, in the precursor suspension of step c) may be in a range from > 0.0001 g/mL to < 0.2 g/mL, preferably in a range from > 0.001 g/mL to < 0.1 g/mL, more preferably in a range from > 0.001 g/mL to < 0.05 g/mL.

In step d) the precursor suspension obtained from step c) is dried. The precursor may be separated from the precursor suspension for example by filtering. The precursor further may be washed from residues such as by rinsing with water. Preferably the precursor suspension obtained from step c) is dried without previous filtering thereby advantageously maintainig the stoichiometric amount of lithium in the solvent without any lost.

In preferred embodiments, the drying in the step d) is performed using a drying method selected from from the group consisting of evaporating, freeze drying and spray drying.

Freeze-drying is preferred. Preferably the drying in the step d) is performed under temperature control. The temperature may be in a temperature range from -120 °C to 120 °C. Preferably the drying time is a range of > 30 minutes to < 168 h, preferably in the range of > 48 hours to < 120 hours, more preferably in the range of > 60 hours to < 96 hours.

In step e) the dried precursor obtained from step d) is calcined thereby forming the lithium metal oxide surface modified with carbonaceous compounds. The calcination converts the metal material of the precursor to the desired crystal phase. Further, the calcination converts the template to carbon and/or carbonacious compounds. Preferably, the calcination temperature is in a range of > 300 °C to <1200 °C, preferably in the range of > 600 °C to < 1000 °C, more preferably in the range of > 700 °C to < 900 °C. A suitable temperature may be selected in accordance with the desired metal oxide. For the synthesis of lithium- manganese-cobalt/nickel oxides, the calcining temperature preferably lies in the range from > 700 °C to < 900 °C, more preferably at about 800 °C. The calcination time may be in a range of > 1 to 30 < hours, preferably in the range of > 6 hours to < 24 hours, more preferably in the range of > 12 hours to < 20 hours.

Such parameters are particularly suitable to obtain a surface modification content of carbonaceous compounds or elemental carbon comprised between 0.001 wt% and 10 wt%, preferably between 0.01 wt% and 5 wt%, more preferably between 0.01 wt% and 2 wt%. The method advantageously provides a facile one-step approach to form a porous structure and a surface that is modified with carbonaceous compounds during a calcination or annealing process. The mechanism sacrifices the template at high temperature, in order to form the porous structure of the material as well as temporarily create a carbonthermal environment. Without being bound to a special theory, it is assumed that at the beginning of the synthesis, a limited amount of transformed template reacts with the particle surface and results in a carbonaceous compound-modified surface. The template can be transformed into the carbonaceous compounds including C-C, C-O, 0-C=0 and a carbon atom bond to a species with three oxygens on the surface of highly crystal particles of a lithium-rich material. Another aspect refers to a lithium metal oxide of the formula Lii _+x Mn _y Mi_ _x _ _y 0 ₂ (I) wherein 0 < x < 0.33 and 0 < y < 1, and wherein M is one or more metal selected from the group consisting of Al, Ni, Co, Cr, Ca, Zr, Nb, Mo, Sr, Sb, V, Ti and Fe, and wherein the lithium metal oxide is surface modified with carbonaceous compounds, prepared by the method according to the invention. M preferably is one or two transition metal selected from Ni and Co. The lithium metal oxide may be a porous oxide. Preferably manufactured are porous lithium-rich layered oxides with a surface that is modified by carbonaceous compounds. The porous lithium metal oxide can have a desorption average pore diameter in a range from > 1 nm to < 500 nm, preferably in a range from > 3 nm to < 300 nm, more preferably in a range from > 5 nm to < 200 nm. The lithium metal oxide may have a BET surface area in the range from > 0.5 m 2 /g to < 50 m 2 /g, preferably in the range from > 1 m 2 /g to < 30 m 2 /g, more

2 2

preferably in the range from > 2 m /g to < 20 m /g. The porous lithium metal oxide surface modified by carbonaceous compounds has a large surface area which is well protected by the surface layer, provides improved electrochemical performance and thus is advantageously usable as electrode material.

Another aspect refers to an electrode material for electrochemical energy storage devices, particularly for lithium and lithium-ion batteries, comprising a lithium metal oxide of the formula Lii _+x Mn _y Mi_ _x _ _y 0 ₂ according to the invention. Preferably the electrode material is prepared by the method of the invention. A further aspect relates to an electrode comprising as electrode material a lithium metal oxide according to the invention or a lithium metal oxide prepared by the method of the invention. Another aspect of the invention refers to an electrochemical energy storage device, comprising an electrode which comprises a lithium metal oxide of the invention prepared by the method of the invention. The term "electrochemical energy storage device" encompasses single-use batteries (primary storage cells) and rechargeable cells (secondary storage cells). In the general terminology, however, rechargeable cells are frequently designated likewise using the term "battery", which is widely used as a generic term. For example, the term "lithium ion battery" is used synonymously with "rechargeable lithium ion battery". Lithium-based energy storage devices are preferably selected from the group comprising primary lithium batteries, primary lithium ion batteries, secondary lithium ion batteries, primary lithium polymer batteries, or lithium ion capacitors. Preference is given to primary and secondary lithium ion batteries. The electrochemical energy storage device particularly is a lithium-ion battery, a lithium-ion capacitor or a super capacitor. A lithium-ion battery for example can comprise a positive electrode, a negative electrode, an electrolyte disposed between the positive electrode and the negative electrode, wherein the positive electrode comprises active material prepared by the method as described.

Another aspect of the invention refers to the use of the lithium metal oxide prepared of the invention or prepared by the method according to the invention as electrode material for electrochemical energy storage devices, particularly as active material for electrodes used in lithium-ion batteries, lithium-ion capacitors and super capacitors.

Unless otherwise defined, the technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

Examples and figures which serve for illustrating the present invention are indicated hereinafter.

The figures, in this context, show the following:

Figure 1 a scan electron microscope (SEM) photograph of Li-rich material obtained in comparative example 1 under 30k magnification.

Figure 2 shows a SEM photograph of the Li-rich material obtained obtained in comparative example 2 under 20k magnification.

Figure 3 shows a SEM photograph of the Li-rich material obtained in example 3 under 30k magnification.

Figure 4 shows in Figure 4A the nitrogen adsorption-desorption isotherms of the Li-rich material obtained in examples 1 and 3, and in 4B the respective BJH Adsorption dV/dw Pore Volume.

Figure 5 shows the powder X-ray diffraction (XRD) pattern of Li-rich material obtained in example 3 in the 2Θ ranges from 15-90°. Figure 6 shows X-ray photoelectron spectroscopy for C Is, Ols and Mn2p of the Li-rich material obtained in example 3.

Figure 7 shows a SEM photograph of the Li-rich material obtained in comparative example

4 under 20k magnification.

Figure 8 shows the rate capability of the Li-rich material of comparative example 1 under

0.1C, 0.2C, 0.5C, 1C, 2C, 5C, IOC (1C=250 mAh g ^"1 ).

Figure 9 shows the rate capability of the Li-rich material of example 3 under 0.1C, 0.2C,

0.5C, 1C, 2C, 5C, IOC (1C=250 mAh g ^"1 ).

Figure 10 shows the cycling performance of Li-rich material of comparative example 1

under 0.5C.

Figure 11 shows the cycling performance of the Li-rich material of example 3 under 0.5C;

inset shows the corresponding long term cycling performance at 2C after 3 formation cycles at 0.5 C.

Figure 12 shows the average voltage as a function of cycle number for the Li-rich material of example 1.

Figure 13 shows the average voltage as a function of cycle number for the Li-rich material of example 3.

Comparative Example 1

Preparation of Li-rich material using a co-precipitation method

The material was synthesized by solid-state reaction from the mixture of lithium hydroxide hydrate (LiOH H ₂ 0), and manganese-nickel-cobalt hydroxide precursor. The manganese- nickel-cobalt hydroxide precursor was prepared by co-precipitating the aqueous solution of Mn, Ni, and Co metal acetate salts in a stoichiometric ratio of 56: 16:8, with lithium hydroxide. After extensive rinsing with distilled water, the precipitate was dried under vacuum at 120 °C overnight. The dried material was then mixed with a stoichiometric amount of LiOH H ₂ 0 by ball milling for 5 h. After suitable grinding, the mixture was calcined in air at 800 °C for 20 h. Experiment parameter, the raw materials, amounts and experimental conditions are shown in Table 1 and Table 2.

Table 1 : metal salts

Table 2: experimental conditions

The calcined particles were then used for evaluation of particle morphology using field- emission scanning electron microscopy (FE-SEM, Zeiss Auriga® microscope). The morphology of the obtained Li -rich material particles is shown in Figure 1. As can be seen in Figure 1, the Li ₁ . ₂ Mno.56Nio.i6Coo.08O2 particles prepared by the co-precipitation method had a strongly agglomerated morphology. The particles had sizes in a range from 10 nm to 300 nm.

The Li -rich material further was characterised by determination of the surface area by means of nitrogen gas adsorption by the Brunauer-Emmett-Teller (BET) method. For this purpose an ASAP 2020 (Accelerated Surface Area and Porosimetry Analyzer, Micromeritics) was used. Also desorption average pore volume was calculated on the Micrometrics ASAP 2020 using Barrett- Joyner-Halenda (BJH) analysis. The BET surface area for sample 1 was 2.04 m7g, and desorption average pore width was 192.9 A.

Comparative example 2

Preparation of Li-rich material without template a) Preparation of a manganese transition metal salt solution

Stoichiometric amounts of manganese acetate, nickel acetate and cobalt acetate (all Sigma Aldrich) as given in Table 3 were solved in 50 ml of deionized water under stirring for 10 minutes. b) preparation of a lithium salt containing alkaline solution

7.5 ml of ammonium hydroxide solution, 28% N¾ in H ₂ 0 (Sigma Aldrich), was mixed with 37.5 ml deionized water and 5 ml ethanol. 0.719g of LiOH H ₂ 0 (Sigma Aldrich) were added and under stirring for 10 minutes. c) preparing a precursor suspension

Under N ₂ atmosphere the aqueous manganese solution of step a) was added to the alkaline solution of b) at a temperature of 55°C under stirring. The resulting suspension solution was kept at 55 °C under stirring for 4 hours. After 4 hours the suspension was left to cool to room temperature. d) drying the precursor suspension

The suspension thereafter was dispersed in 20 ml of deionized water and freeze dried (Christ Beta 2-4 LD Plus LT) at - 105 °C for 72 h. e) Calcination of the dried precursor

1.7 g of the precipitate obtained from step d) were transferred to a muffle furnace. The muffle furnace was sealed and the precipitate was calcined in air at 800 °C for 20 h. Afterwards the furnace was cooled to room temperature. The as prepared lithium-rich oxide powder was briefly for about 30 seconds mortared by hand. The experimental parameters, the raw materials, amounts and experimental conditions are summarized in Table 3 and Table 4. The calcined particles were then used for evaluation of particle morphology using SEM. The morphology of the obtained Li-rich material particles is shown in Figure 2. The particles of example 2 showed a kind of polygonal prism and a diameter distribution from 50 nm to 300 nm. The particles were agglomerated with each other.

Example 3

Preparation of Li-rich material with template

3.1 Preparation of polystyrene (PS) template

A polystyrene containing solution was synthesized by an emulsion polymerization method. 0.12 g of potassium persulfate (KPS) as an initiator and 0.4 g sodium dodecyl sulfate (SDS) as a surfactant were dissolved in a mixture of 200 ml distilled water and 50 ml ethanol in a 500 ml three-neck flask. Then 40 ml styrene monomer were added drop-wise to the mixture under Ar atmosphere and continuous rapid stirring. A colloidal suspension with dispersed polystyrene was obtained by continuously stirring the mixture at 70°C for 8 hours. The resulting concertation of polystyrene solution was 0.02 g/ml. Polystytrene particles had a particle size of 50 to 200 nm, wherein the particles mainly had a particle size from 60 to 100 nm were obtained.

3.2 Preparation of Li-rich material using polystyrene template

a) Preparation of a manganese transition metal salt solution comprising template

Stoichiometric amounts of manganese acetate, nickel acetate and cobalt acetate (all Sigma Aldrich) as given in Table 3 were solved in 50 ml of deionized water under stirring for 10 minutes. To this solution 5 ml of the polystyrene solution of step 3.1 were added, yielding a final concentration of 0.0018 g/ml of template in the suspension, and the mixture was then heated up to 55 °C under stirring for 2 hours. The solution appeared like a clear gel. b) preparation of a lithium salt containing alkaline solution

7.5 ml of ammonium hydroxide solution, 28% N¾ in H ₂ 0 (Sigma Aldrich), was mixed with 37.5 ml deionized water and 5 ml ethanol. 0.719g of LiOH H ₂ 0 (Sigma Aldrich) were added and under stirring for 10 minutes. c) preparing a precursor suspension

Under N ₂ atmosphere the aqueous solution containing the metal salts and the template of step a) was added to the alkaline solution of b) at a temperature of 55°C under stirring. The resulting suspension solution was kept at 55 °C under stirring for 4 hours. After 4 hours the suspension was left to cool to room temperature.

Drying the precursor suspension and calcination of the dried precursor was performed as described under steps d) and e) of example 2. The experimental parameters, the raw materials, amounts and experimental conditions are summarized in Table 3 and Table 4.

The calcined particles were then used for evaluation of particle morphology using SEM. The morphology of the obtained Li -rich material particles is shown in Figure 3. The Figure 3 shows that the primary particles were high crystalline with uniform distribution. The average particle diameter was 150 nm. The primary particles were inner-connected to form a porous morphology. The pores were homogeneous dispersed in the structure and the pore size was from 150 nm to 400 nm.

The Li -rich material further was subjected to determination of surface area and desorption average pore volume using the Micrometrics ASAP 2020. The BET surface area for the porous Li-rich material was determined to 9.17 m /g, and desorption average pore width to 233.5 A. The Figure 4A shows the nitrogen adsorption-desorption isotherms of the lithium- rich material of comparative example 1 and the porous lithium-rich material of example 3. The nitrogen adsorption/desorption isotherms shown in Figure 4 A indicate that the pore volume of the porous lithium-rich material was much larger than that of the lithium-rich material of comparative example 1. A capillary condensation effect of the lithium-rich material of example 3 resulted in a quite obvious hysteresis at high p/p ₀ range, indicating that pores exist in the particles of the sample.

The Figure 4B shows the BJH Adsorption Pore Volume dV/dw of the lithium-rich material of comparative example 1 and the porous lithium-rich material of example 3. The BJH curves from Figure 4B indicate a relative pore size of under 200nm of both samples. Although, a wide low peak could be observed for the lithium-rich material of example 1, this can be explained as the void space formed by the agglomerate particles. For the porous lithium-rich material of example 3, two high peaks appear in the range from 2 to 200 nm, including microspores, mesopores and macrospores. The majority of porous are the mesopores, which is obtained when the occupied template burn out during calcination.

The crystal structure of the porous lithium rich oxide was characterized by X-ray diffraction (XRD) in the 2Θ range of 25-90 ° at a scan rate of 0.0196 °/step on a Bruker D8 Advance (Germany) with Cu K _a radiation at room temperature. Figure 6 shows the powder X-ray diffraction (XRD) pattern of the porous Li-rich material. As shown in Figure 5, the observed diffraction peaks in the XRD pattern could be clearly determined as belonging to

Li ₁ . ₂ Mno. ₅₆ io.i ₆ Coo.08O2. No peaks assigned to a spinel-phase were observed.

Advantageously, no signs of impure layered structure, which would add shoulders next to the main diffraction peaks, in peculiarly the (003), (101), and (104) peaks, were observed. The metal oxide manufactured by the method of the invention thus is characterised by to possess a crystalline structure.

Figure 6 shows X-ray photoelectron spectroscopy for Cls, Ols and Mn2p of the porous Li- rich material. As can be seen particularly from the Cls signals several types of surface carbon compounds, such as sp ² C-C (284.4eV), amorphous C-C bonds (285eV), C-0(286.8eV), O- C=0(288.8eV) and a carbon atom bond to a species with three oxygen (290. leV) was detected. It is assumed that layered or surface modified organic or lithium-poor semi alkyl carbonates such as ROC0 ₂ Li or polymeric-type ROC0 ₂ R' with R and R' being alkyl groups were formed on the surface of the porous material. The polystyrene template transformed into the carbonaceous compound including C-C, C-O, 0-C=0 and a carbon atom bond to a species with three oxygens on the surface of the highly crystal Li-rich material particles which thus is surface modified with carbonaceous material. The content of carbon, nitrogen and hydrogen were determined by CHN elemental analysis (CHN-O-Rapid, Heraeus) through thermal decomposition. The analysis requires high temperature (1800°C) combustion in an oxygen-rich (high purity oxygen) environment. These combustion products are carried by inert gas (helium) to pass through high purity copper and the absorbent traps (GC-type gas filter), only carbon dioxide, water and nitrogen are left for further thermal conductivity detection. A Vario EL III Element Analyzer was employed to determine the residual amount of carbon, nitrogen and hydrogen, the sample weight was 50 mg, and determination was done in triplicate. The relative concentration had no effect on baseline resolution of all CHN peaks due to thermally controlled purge and trap technique. The weight percent of C was determined to be 0.2%wt, H was 0.25 %wt and N 0 %wt.

Comparative Example 4

Preparation of Li-rich material with excess template

The preparation was performed as described in example 3, with the exception that in step a) for the preparation of the metal salt solution comprising template 25 ml of the polystyrene solution of step 3.1 were used. The experimental parameters, the raw materials, amounts and experimental conditions are summarized in Table 3 and Table 4. Figure 7 shows the SEM photograph of the Li-rich material obtained. As can be taken from the Figure 7, the higher reducing atmosphere significant changed the structure. As a result, the particles formed a quite different morphology. The particle size which is displayed in Figure 7 demonstrates that the majority of primary particles increased up to 200 nm. Larger particles reduce the contact area of active material with an electrolyte and increase the lithium ion diffusion path which leads to a poor electrochemical performance. Moreover, more impurities are contained in the crystal structure, and as impurities are a non-active component, this also reduces the electrochemical performance of the resulting material. Experimental parameter, the raw materials, amounts and experimental conditions of examples 2 to 4 are summarized in Table 3 and Table 4.

Table 3 : metal salt and alkaline solutions

Table 4: Calcination conditions

Example Calcination

temperature time

2 800 °C 20 h

3 800 °C 20 h

4 800 °C 20 h Electrochemical characterization

Electrode preparation:

As active material for cathode electrodes the lithium-rich oxide of comparative example 2 and the porous lithium-rich oxide surface modified with carbonaceous compounds of example 3, respectively, were used. Cathode electrodes were prepared by casting a slurry of the respective active material, Super C65 conductive agent and polyvinylidene fluoride (PVdF) binder at a dry weight ratio of 80: 10: 10, onto aluminum foil and drying overnight in a vacuum at 80 °C. The slurry was prepared by magnetic stirring for 12 h. The mass loading values of the active material was about 2 mg cm ^" . The active material mass loading was determined by weighting the electrodes, in a dry room or a glove box at room temperature, then the weight was divided by the area of the coated aluminum foil.

The electrodes were assembled into CR2032 coin cells with lithium metal as counter electrode and 1M LiPF ₆ in 3:7 (by weight) ethylene carbonate (EC) : dimethyl carbonate (DEC) as electrolyte. Galvanostatic cycling measurements were carried out at 20°C on a Maccor series 4000 battery tester in a voltage range of 2-4.8 V (nominal current, 1 C = 250 mA g ^"1 ). Since lithium foil was used as counter and reference electrode, potential values given are referring to the Li ⁺ /Li reference couple.

Comparative Example 5

Electrochemical characterization of the lithium-rich oxide of comparative example 1

Figure 8 shows the rate capability of the Li-rich material of comparative example 1 under 0.1C, 0.2C, 0.5C, 1C, 2C, 5C, IOC (1C=250 mAh g-1). As can be taken from Figure 8, being used as cathode material for lithium-ion battery, the material of example 1 only delivered a capacity of about 250 mAh g ^"1 at 0.1C and achieve about 50 mAh g ^"1 at IOC. Figure 10 shows the cycling performance of Li-rich material of comparative example 1 under 0.5C. As can be taken from Figure 10, the capacity was not stable, but faded after 100 cycles to below 150 mAh g ^"1 . Figure 12 shows the average voltage as a function of cycle number. As can be taken from Figure 12, the average charge voltage performed a visible increasing trend which indicates an escalating of the inner resistance. The rapid decay of the average discharge voltage reveals that a strong layered-to-spinel phase transformation occurred during the long- term cycling.

Example 6

Electrochemical characterization of the lithium-rich oxide of example 3

Figure 9 shows the rate capability of the Li-rich material of example 3 under 0.1C, 0.2C, 0.5C, 1C, 2C, 5C, IOC (1C=250 mAh g ^"1 ). As can be taken from Figure 9, being used as cathode material for lithium-ion battery, the porous structure Li-rich material with

carbonaceous compound modified surface could deliver a capacity above 270 mAh g ^"1 at 0.1 C and achieve 119.5 mAh g ^"1 at IOC. Figure 11 shows the cycling performance of the Li-rich material of example 3 under 0.5C; inset shows the corresponding long term cycling performance at 2C after 3 formation cycles at 0.5C. Furthermore, the material showed only minor capacity loss after 100 cycles at 0.5 C and maintains 94.9% of its initial capacity after 500 cycles at 2 C, as shown in Figure 11. Figure 13 shows the average voltage as a function of cycle number for the Li-rich material of example 3. The decrease of the mean charge voltage from 1 ^st to 2 ^nd cycle can be explained as an effect of irreversible structure change during the electrochemical activation of the Li ₂ Mn0 ₃ -region in the initial cycle. The average charge and discharge voltage showed only negligible decreasing, corresponding to a lower inner resistance and more stable structure during the cycling. Even more notably, the speed of "voltage decay" during cycling was also decreased.

In summary, it could be shown that the lithium rich oxide Lii. ₂ Mno.56Nio.i6Coo.o80 ₂ with porous structure and a carbonaceous compound-modified surface of the present invention is obtainable in a one-step synthesis. Compared to the state of art cathode material when used as positive electrode material the Li-rich material material showed improved electrochemical performance in specific capacity and cycling stability, providing a discharge capacity of about 150 mAh g ^"1 under 2 C that was maintained longer than 500 cycles.

Hence, the present invention provides for electrode material for lithium-ion batteries, sodium- ion batteries, Li, Na metal batteries and super capacitors with an increased power density and enhanced power supply and also show the possibility of realizing commercialization with Li metal, lithiated metals, sodium metal or other reactive metals, lithium titanium oxides, alloy as well as other anodes in aqueous, non-aqueous, ionic liquids, polymers or ceramic electrolytes.