Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/36—Selection of substances as active materials, active masses, active liquids
  • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
  • H01M4/50—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
  • H01M4/505—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/02—Details
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/05—Accumulators with non-aqueous electrolyte
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
  • H01M4/131—Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/36—Selection of substances as active materials, active masses, active liquids
  • H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/05—Accumulators with non-aqueous electrolyte
  • H01M10/052—Li-accumulators
  • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02E60/10—Energy storage using batteries

Definitions

• the present application relates to cathode materials for a battery and more specifically to ruthenium (Ru) doped, lithiated manganese oxide materials with a spinel crystal structure used in the cathode terminal of lithium-ion and lithium rechargeable batteries to greatly enhance the cyclic performance of the cathode material at a high work voltage and a high current density.
• ruthenium (Ru) doped, lithiated manganese oxide materials with a spinel crystal structure used in the cathode terminal of lithium-ion and lithium rechargeable batteries to greatly enhance the cyclic performance of the cathode material at a high work voltage and a high current density.
• High lithium containing batteries are extensively used in modern life as electrochemical power sources.
• Lithium-ion secondary battery has been widely used in mobile phones, laptops and other modern appliances.
• the cathode of a typical rechargeable lithium-ion battery uses a transition metal oxide material that can reversibly intercalate/deintercalate lithium at a high potential difference when carbon, for example, is used as the anode material.
• the first commercial lithium-ion batteries introduced in 1990 by Sony Corporation used LiCoO 2 as the cathode material, which continues to be used in more than 90% of lithium-ion batteries.
• LiCoO 2 has a well-ordered layered crystal structure, which is easily prepared and enables a fast and reversible lithium intercalation.
• LiCoO 2 has poor thermal stability and is toxic, rendering it unsuitable for large-sized battery applications, such as electric and hybrid vehicles, that require batteries to be stable, economical and environmentally friendly, along with good performance.
• cathode materials have been developed for many years. These other cathode materials can be divided into cathode materials having a spinel crystal structure and cathode materials having an olivine crystal structure.
• a typical cathode material with an olivine crystal structure for example, LiFePO 4 , has high theoretical capacity of about 170mAh/g, low cost and non toxicity.
• the electronic conductivity of this type of cathode materials is poor, limiting its use in high charge/discharge rate applications, for example, in hybrid vehicles. Many methods have been researched to improve the conductivity of olivine lithium-based cathode materials.
• LiFePO 4 particles have been coated with a thin carbon layer or doped with some metal cations, and nano-sized cathode particles have been synthesized. These methods have improved the electric conductivity.
• Manganese oxides having a spinel crystal structure offer lower cost and lower toxicity compared to cobalt, and have been demonstrated to be safer when overcharged.
• the most readily prepared lithiated manganese oxide with a spinel crystal structure is LiMn 2 U 4 .
• LiMn 2 U 4 includes three-dimensional channels, which allow for lithium diffusion.
• Lithiated manganese oxide has a high work voltage (around 4.2V), but a lower capacity than that of LiCo ⁇ 2 , and low stability due to J-T distortion during lithium intercalation/de-intercalation.
• LiM ⁇ O 4 has been doped with transition metals such as Cr, Ni and Cu among which LiNio. 5 Mn 1 . 5 O 4 shows a higher work voltage (around 4.5-4.7V), a large capacity (around 147mAh/g) and a relatively good cycle performance below a relative high current density of around 147mA/g.
• LiNio. 5 Mn 1 . 5 O 4 is a promising cathode material for applications requiring high work voltage especially for hybrid vehicles.
• the cycle performance of LiNi 0 . 5 Mn I-5 O 4 at high current density is poor due to its structure instability and limited conductivity.
• the present invention in one aspect advantageously provides a method of improving the cycle performance of LiNio. 5 Mn 1 . 5 O 4 at high current density with Ru doping.
• An object of the present invention is to develop a novel cathode material for use in a battery.
• a novel material according to the present invention is to develop ruthenium (Ru) doped LiNio. 5 Mn 1 . 5 O 4 cathode material with a spinel structure. Ru is a metal with a large oxidation state extending from +2 to +8.
• Another object of the present invention is to produce Ru doped LiNi 0 . 5 Mn I-5 O 4 cathode material powders that exhibit good electrochemical properties at high current density.
• a battery according to the present invention includes a first terminal and a second terminal, in which the first terminal is made from a lithiated manganese oxide doped with ruthenium, the lithiated manganese " ⁇ x ⁇ de " including lithium and manganese and having a spinel crystal structure.
• the ruthenium doped lithiated manganese oxide further comprises a transition metal, which may be selected from a group consisting of Cr, Ni, Cu.
• the ruthenium may reside in one of positions for the transition metal within the crystal structure, positions for lithium within the crystal structure, and positions of the transition metal and positions for the lithium within the crystal structure.
• Ruthenium as used in the present invention can have a valence of 2 + to 8 + .
• nickel is the transition metal
• ruthenium resides in the nickel positions in the crystal structure with a formula Li [Li (c -2) ⁇ RU ⁇ Ni 0 .5-(c- D ⁇ ]Mni. 5 ⁇ 4 in which x is a number in the range 0.0001 to 0.5/(C-I), C being the valence of the ruthenium.
• x can be in the range of 0.0001 to 0.1666.
• nickel is the transition metal
• ruthenium resides in the lithium positions within the crystal structure with a formula Li 1- . C x Ru x Ni 0 . 5 Mni. 5 ⁇ 4 in which x is a number in the range 0.0001 to 0.5/C, C being the valence of ruthenium.
• x can be in the range of 0.0001 to 0.125.
• nickel is the transition metal and ruthenium resides in the nickel positions within the crystal structure with a formula LiRu x Nio.5-( c ⁇ /2 )Mni. 5 ⁇ 4 in which x is a number in the range 0.0001 to 1/C, C being the valence of ruthenium.
• x can be in the range of 0.0001 to 0.25.
• a process for the synthesis of a material according to. the present invention includes mixing of a lithium compound, a transition metal compound, a manganese compound, and a ruthenium compound to obtain a mixture/ calcining the mixture/ and firing the calcined mixture.
• the lithium compound can be selected from a group consisting of Li 2 C ⁇ 3 , Li 2 O, and LiOH
• the transition metal compound can be selected from a group consisting of N 1 O, NiC ⁇ 3 , and Ni (OH) 2
• the manganese compound is selected from a group consisting of MnO 2 , and Mn(OH) 4
• the ruthenium compound is RuO 2 .
• the amount of each compound is selected so that the ruthenium doped lithiated manganese oxide is charge neutral.
• the calcining can be carried out at a calcination temperature in the range 200-700 0 C for a period of time in the range 1 to 50 hours.
• the firing can be carried out at a firing temperature in the range 600-1400 0 C for a period of time in the range 1 to 50 hours.
• the calcining and the firing are carried out with intermittent grinding of the mixture.
• Fig. IA shows the x-ray diffraction (XRD) spectra of Ru doped LiNi 0 . 5 Mn x-5 O 4 powder system before the calcining and the firing process.
• Fig. IB shows the x-ray diffraction (XRD) spectra of Ru doped LiNi 0 . 5 M11 1 . 5 O 4 powder system after the calcining and the firing process.
• Figs. 2A-2C show scanning electron microscopy
• Fig. 3 shows data relating to the electrical conductivities of LiNio. 5 Mn 1 . 5 O 4 and Li1. 1 Nio. 35 Ruo.05Mn1.5O4 measured at different temperatures.
• Fig. 4 shows data relating to the capacity retention of LiNio.5Mn 1 . 5 O 4 , Li 1 . 1 Nio. 35 Ruo. 0 5Mn1. 5 O4 and LiNio. 4 Ruo. 05 Mn1. 5 O 4 charged/discharged at high current density 1470mA/g.
• Fig. 5 shows data relating to the rate capacity of LiNio. 5 Mn 1 . 5 O 4 , Li 1 . 1 Nio. 35 Ruo. 05 Mn 1 . 5 O 4 and LiNio. 4 Ruo. 05 Mn 1 . 5 O 4 charged at 29.4mA/g (0.2C) and discharged at different current densities.
• Figs. 6A-6B show a comparison of Nyquist plots from -20 0 C to 40 0 C of LiNi 0 . 5 Mn x-5 O 4 (Fig. 6A) and Li 1 .1Nio. 35 Ruo. 0 5Mn 1 . 5 O 4 (Fig. 6B) pellets sintered at 800 0 C for l ⁇ hours and 1000 0 C for 2 hours.
• Fig. 7 discloses data relating to the electric conductivity measurements showing that the electronic conductivity increases with increase in Ru concentration.
• Fig. 8 shows data relating to the capacity retention of Lio. 88 Ruo. 03 Nio. 5 Mn 1 . 5 O 4 . charged/discharged at high current density 1470mA/g.
• a typical battery includes a first terminal (e.g. a cathode terminal) and second terminal (e.g. an anode terminal) .
• the first cathode terminal of a battery is made from lithiated manganese oxide (LiMn 2 O 4 ) having a spinel crystal structure which has been doped with ruthenium.
• the lithiated manganese oxide according to the present invention is preferably doped with a transition metal such as chromium (Cr) , nickel (Ni) , or copper (Cu) in which the ruthenium atoms reside in positions that would be occupied by lithium atoms within the crystal structure (i.e.
• nickel is used as a transition metal and ruthenium can occupy lithium positions within the crystal structure, or nickel positions within the crystal structure of the lithiated manganese oxide, or both.
• Ruthenium as used in the present invention can have a valence of 2 + to 8 + .
• Li [Li ( c- 2 ) ⁇ Ru x Nio. 5 - ⁇ c-i) ⁇ ]Mni. 5 0 4 (Formula 1) is a formula for one material system according to the present invention, in which x is a number in the range 0.0001 to 0.5/(C-I), C being the valence of the ruthenium. It should be noted that in this material system the ruthenium content should be selected so that the total ion content after doping should result in charge neutrality. Thus, for ruthenium of valence 4 + , x can be in the range of 0.0001 to 0.1666 and the formula can be rewritten as Lii + 2 X Ru x Nio. 5 -3 X Mni.
• LiRu x Nio. 5 -(c x/2 )Mni.5 ⁇ 4 (Formula 2) is another formula for a material system in which ruthenium replaces nickel atoms in the crystal structure.
• x is a number in the range 0.0001 to 1/C, C being the valence of ruthenium.
• x can be in the range of 0.0001 to 0.25.
• ruthenium partly replaces nickel ions in the material system.
• Li 1 -c x RUxNio. 5 Mn 1 . 5 O 4 (Formula 3) is a formula for a material system in which ruthenium partly replaces lithium in the crystal structure.
• x is a number in the range 0.0001 to 0.5/C, C being the valence of ruthenium.
• x can be in the range of 0.0001 to 0.125.
• each formula can be rewritten as (A)MnI -5 O 4 in which A is one of Lii +(C - 2) ⁇ Ru x Ni 0 .5-(C-Dx/ LiRu x Ni 0 .5-(cx/2) and Lii_ C ⁇ Ru x Ni 0 .5 • It should be noted that while the examples disclosed are based on a spinel crystal structure having a general formula LiNio. 5 Mn 1 .
• O4 could be 0(4- a) , where a is larger than 0 and Mn and Ni may not have 4 + and 2 + valences.
• the compound may include Mnn.s- b j and Ni(o. 5 - C ), where b and c are numbers larger than 0.
• a method for the synthesis of a material according to the present invention includes mixing of a lithium compound, a nickel compound, a manganese compound, and a ruthenium compound to obtain a mixture; calcining the mixture; and firing the calcined mixture.
• the calcining and the firing can be intermittently interrupted and the mixture is subjected to grinding.
• the lithium compound can be selected from a group consisting of LiaCO 3 , Li 2 ⁇ , and LiOH, the nickel compound
• fc can be selected from a group consisting of NiO, NiC0 3 , and Ni (OH) 2 or other Ni containing compounds
• the manganese compound is selected from a group consisting of Mn ⁇ 2, and Mn(OH) 4 or other Mn containing compounds
• the ruthenium compound is RuO 2 or other Ru containing compounds.
• the calcining can be carried out at a calcination temperature in the range 200-700 0 C for a period of time in the range 1 to 50 hours. In one preferred embodiment, the mixture is calcined for 2 hours.
• the firing can be carried out at a firing temperature in the range 600-1400 0 C for a period of time in the range 1 to 50 hours.
• ruthenium content should be selected so that even with doping the material will be charge neutral.
• the compounds for the mixture are preferably metal oxides but can be other compounds.
• the mixing can be carried out by ball milling, co-precipitation, sol-gel or the Pechini process wherein the mixing is conducted for a period of time sufficient to form a homogeneously distributed powder.
• the metal oxide precursors/compounds can be initially mixed together with an oxide of ruthenium cations.
• the mixture is preferably ball milled for about 1 to 3 hours, or, alternatively, dissolved in an appropriate solvent under constant stirring for 1 to 24 hours.
• All precursors are preferably ball milled for at least 1 hour or dissolved in solution under constant stirring for at least 1 hour to achieve at least some degree of homogeneity.
• the properties and the quality of the powders may be altered by altering the processing parameters, such as calcination temperature, sintering temperature and dwell time. These parameters are advantageously controlled in order to achieve optimal performance . Examples
• Example 1 Ru doped in Ni positions - Formula 1 and Formula 2 systems
• C is 4+, whereby the formula can be rewritten in terms of ruthenium content as Lii + 2 X Ru x Nio.5- 3 ⁇ Mni. 5 U 4 (Formula 1) and LiRu x Nio. 5 - 2X Mni. 5 ⁇ 4 (Formula 2) .
• Stoichiometric amounts of LiOH, NiO, MnO 2 and RUO 2 were mixed according to corresponding Formula 1 and Formula 2, respectively.
• Fig. IA and IB show the X-ray diffraction (XRD) spectra of the Lin- 2x Ru x Nio. 5 - 3x Mn 1 . 5 O 4 powder system before and after solid state reaction.
• Fig. IA shows the ball milled powder mixture XRD spectrum where NiO, Mn ⁇ 2 and RUO 2 diffraction peaks can be seen.
• Lii +2 ⁇ Ru x Ni 0 . 5 - 3 ⁇ Mni. 5 ⁇ 4 reaches a maximum capacity of about 70mAh/g after several cycles and the capacity remains almost constant without change after 500 cycles; whereas, the LiNi 0-5 Mn I-5 O 4 system reaches its maximum capacity of about 65mAh/g, and drastically reduces to 40mAh/g after 500 cycles. It is shown that LiRu x Ni 0-5 - 2 X Mni -5 ⁇ 4 can deliver the highest capacity of lllmAh/g.
• the rate capacity of these three material systems is plotted in Fig. 5 where the three systems were cycled at the same charging rate but different discharge rates.
• ruthenium is doped in lithium ion sites leading to the formation of some lithium ion vacancies.
• Stoichiometric amounts of LiOH, NiO, MnO 2 and RuO 2 were mixed according to corresponding Formula 3. The mixture was first ball milled for 120 min to form a powder mixture. After ball milling, calcination was carried out at 650 0 C for 3,000 minutes. Due to partial replacement of lithium ions by ruthenium ions, the capacity is slightly reduced at low charge and discharge rates. However, at the high charge and discharge rate of 1OC (1470 it ⁇ A/g) , its capacity is higher than that of LiNio. 5 Mn 1 . 5 O 4 (Fig. 8) . In addition, there is almost no capacity fade at a 1OC rate.

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• 2009
  • 2009-11-23 MY MYPI2011002188A patent/MY156504A/en unknown
  • 2009-11-23 KR KR1020117012890A patent/KR101711221B1/ko active IP Right Grant
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