TWI493779B - Mixed metal olivine electrode materials for lithium ion batteries having improved specific capacity and energy density - Google Patents

Description

Mixed metal olivine electrode material for lithium ion battery with improved specific capacitance and energy density [incorporated by reference]

All of the patents, patent applications, and publications cited herein are hereby incorporated by reference in their entirety in their entirety herein in theties in the the the the the

[Cross-Reference to Related Applications]

The present application claims the benefit of the earlier filing date of the U.S. Patent Application Serial No. 61/236,862, filed on Aug.

The present invention relates to battery technology.

The battery generates energy from an electrochemical reaction. A battery generally includes: a positive electrode and a negative electrode; an ionic electrolyte solution that supports ions moving back and forth between the two electrodes; and a porous separator that ensures that the two electrodes are not Touch, but allow ions to travel back and forth between the electrodes.

Most of the contemporary portable electronic appliances rely exclusively on rechargeable lithium (Li) ion batteries as a power source. This situation has prompted continued efforts to increase its energy storage capacity, power capability, service life and safety characteristics, and reduce its cost. A lithium ion battery refers to a rechargeable battery having a negative electrode capable of storing a large amount of lithium whose lithium chemical potential is higher than the chemical potential of lithium metal. When the lithium ion battery is being charged, lithium ions travel from the positive electrode to the negative electrode. When discharging, the plasma returns to the positive electrode, at Energy is released during the process.

In a typical Li-ion battery, the battery contains a metal oxide for a positive electrode (or cathode), carbon/graphite for a negative electrode (or anode), and a lithium salt for an electrolyte in an organic solvent. Recently, lithium metal phosphate has been used as a cathode electroactive material.

These Li-ion batteries using lithium iron phosphate (LFP) based cathode materials can be used in a variety of different applications. In certain applications, such as hybrid electric vehicles that charge a battery via energy collected while the vehicle is braking, a battery that exhibits a high specific capacity (or specific power) is desirable, Because of the fast recharge rate and discharge rate of such batteries are important. In other applications, such as plug-in electric vehicles where the distance traveled by the vehicle is based on the total amount of electrical energy that can be stored in the battery, high energy density (or specific energy) ) is what you want. Therefore, materials for Li-ion batteries are optimized for the specific applications that are conceivable.

In one aspect, a positive electrode material is provided in which both energy density and specific capacitance are optimized to achieve both high energy density and high specific capacitance.

In one aspect, a positive electrode material is provided wherein the energy density is at least 340 mWh/g at a 20 C discharge rate. In another aspect, a positive electrode material is provided wherein the specific capacitance is at least 110 mAh/g at a 20 C discharge rate. The power density (i.e., energy density per unit time) is at least 6,800 mW/g at a 20 C discharge rate.

In another aspect, a positive electrode material is provided in which both energy density and specific capacitance are optimized to achieve both high energy density and high specific capacitance. In one embodiment, the energy density is at least 340 mWh/g at a 20 C discharge rate and the specific capacitance is at least 110 mAh/g. The power density (i.e., energy density per unit time) is at least 6,800 mW/g at a 20 C discharge rate.

In one aspect, a lithium iron iron manganese (LFMP) based positive electrode material having an olivine structure is provided which is more doped with one or more doping elements. In an embodiment, the doping element is doped as part of a lattice structure of the olivine structure. In certain embodiments, the doping element may comprise cobalt (Co), nickel (Ni), vanadium (V), niobium (Nb), fluorine (F), or a mixture thereof.

In one or more embodiments, a positive electrode material is provided that includes an electroactive material. Electroactive materials include lithium (Li), iron (Fe), manganese (Mn), one or more dopants (D), and phosphate (PO ₄ ), wherein the amount of Fe + Mn + D is 1.0; Li: ( The ratio of the amount of Fe + Mn + D) is from about 1.0 to about 1.05; the ratio of the amount of PO ₄ : (Fe + Mn + D) is from about 1.0 to about 1.025; and D is one selected from the group consisting of: Or a plurality of dopants: cobalt (Co), nickel (Ni), vanadium (V), niobium (Nb) and mixtures thereof; the amount of Mn is 0.35 to 0.60; the amount of D is from about 0.001 to about 0.10; and electroactive The material includes at least one phase having an olivine structure including at least some of the Li, Fe, Mn, D, and phosphate.

In certain embodiments, the doping metal may be selected from the group consisting of Co, V, Nb, and mixtures thereof. In some embodiments, doped metal It may be selected from a mixture of Co and V.

In certain embodiments, the electroactive material may further comprise fluorine.

In some embodiments, the composition comprises up to about 0.1 mole 1%, 0.5 mole%, 1 mole%, 1.5 mole%, 2 mole%, 2.5 mole%, 3 mole%, 3.5 moles %, 4 mole %, 4.5 mole %, 5 mole %, 6 mole %, 7 mole %, 8 mole %, 9 mole % or 10 mole % of the one or more doped metals . In certain embodiments, the composition comprises up to 0.1 mol%, 0.5 mol%, 1 mol%, 1.5 mol%, 2 mol%, 2.5 mol%, 3 mol%, 3.5 mol% 4 mol%, 4.5 mol% or 5 mol% Co. In certain embodiments, the composition comprises up to 0.1 mol%, 0.5 mol%, 1 mol%, 1.5 mol%, 2 mol%, 2.5 mol%, 3 mol%, 3.5 mol% 4 mol%, 4.5 mol% or 5 mol% Ni. In certain embodiments, the composition comprises up to 0.1 mol%, 0.5 mol%, 1 mol%, 1.5 mol%, 2 mol%, 2.5 mol%, 3 mol%, 3.5 mol% , 4 mole %, 4.5 mole % or 5 mole % of V. In certain embodiments, the composition comprises up to 0.1 mol%, 0.5 mol%, 1 mol%, 1.5 mol%, 2 mol%, 2.5 mol%, 3 mol%, 3.5 mol% , 4 mole %, 4.5 mole % or 5 mole % F.

In one or more embodiments, the one or more dopant metals may be substituted into one or more lattice locations of Li, Fe, or Mn of the olivine structure. In certain embodiments, F can be substituted into one or more phosphate lattice locations of the olivine structure.

In one or more embodiments, the electroactive material can be present primarily in the form of an olivine phase. In one or more embodiments, the electroactive material may contain less The amount of doped metal secondary phase.

In one or more embodiments, a positive electrode is provided that includes a positive electrode material as described herein.

In one or more embodiments, a lithium secondary battery is provided, comprising: a positive electrode in electrical contact with a positive electrode current collector, the current collector being electrically coupled to an external circuit; a negative electrode, and a negative electrode a current collector electrically contacting, the current collector being electrically coupled to an external circuit; a separator positioned between the cathode and the anode and in contact with the cathode and the anode; and an electrolyte interposed with the positive electrode and the negative electrode Contact; wherein the positive electrode comprises a positive electrode material as described herein.

In one or more embodiments, the negative electrode of the lithium secondary battery comprises a lithium interlayer compound or a lithium metal alloy. In one aspect, the negative electrode comprises carbon. In another aspect, the negative electrode comprises graphitic carbon. In still another aspect, the carbon is selected from the group consisting of graphite, spheroidal graphite, metastable phase carbon microbeads, and carbon fibers.

In one or more embodiments, the positive electrode further comprises a binder and a conductive material.

It will be appreciated that although features or embodiments of electroactive materials are individually described, electroactive materials, positive electrode materials, positive electrodes or lithium secondary batteries may have one or more of the features described herein (in any combination) the way).

definition

As used herein, "dopant metal" refers to A metal doped into (or substituted for) an electroactive material of a positive electrode or doped into a lattice site of an electroactive material. In certain embodiments, the doping metal is present at a small concentration (relative to the concentration of the electroactive metal) or has a redox potential that is significantly different from the electroactive metal, such that the doping metal is not significantly helpful Electrical storage capacitor in an electrochemical battery.

As used herein, "olivine structure" refers to a compound based on the formula (M1, M2) ₂ AO ₄ . The olivine structure consists of an isolating tetrahedral AO ₄ anion group and M1 and M2 cations surrounded by six oxygen ions. In general, the olivine structure exhibits orthorhombic 2mmm crystal symmetry and has a plurality of planes defined by zigzag chains and straight chains. The M1 cation typically occupies a tortuous chain of octahedral sites, and the M2 cation typically occupies a linear chain of alternating planes of the octahedral seat. The lattice position can be doped with other doped metals, but still maintain the olivine structure.

As used herein, an "olivine phase" is any crystalline phase having an olivine structure. The olivine phase may comprise one or more doping metals substituted into the lattice structure of the olivine structure. For example, the olivine phase may be based on lithium-iron-manganese-phosphate (LFMP) having the following olivine structure doped with one or more of the lattice positions of the olivine structure Doped with metal.

As used herein, "olivine compound" refers to a material having an olivine structure.

As used herein, "stoichiometric olivine compound" refers to the amount of lithium and/or phosphorus relative to other metals in the material. For example, if the olivine compound is LiFePO ₄ , the ratio of Li:Fe:PO ₄ is 1:1:1 to form a stoichiometric olivine compound. If the olivine compound is Li-Fe-Mn-Co-Ni-V-PO ₄ , the ratio of Li:Fe+Mn+Co+Ni+V:PO ₄ is 1:1:1 to form a stoichiometric olivine compound.

As used herein, "excess lithium" or "lithium rich" refers to the amount of lithium in the total composition that exceeds the amount required to form a stoichiometric olivine compound.

As used herein, "excess phosphorus" or "phosphorus-rich" refers to the amount of phosphorus in the total composition that exceeds the amount required to form a stoichiometric olivine compound.

As used herein, "solid solution" refers to a mixture of different atomic cations and anions that are themselves arranged in a single crystal lattice structure, such as an olivine structure. For example, olivine compounds (such as LFMP and doped metals) that are present together in the form of an olivine phase may be referred to as solid solutions.

As used herein, the term "specific capacitance" refers to a capacitance per unit mass of an electroactive material in a positive electrode and has a unit of milliamp-hours per gram (mAh/g).

As used herein, the term "energy density" refers to the amount of energy that a battery has in relation to its size. The energy density is the total amount of energy (in Wh) that can be stored per electroactive material amount in the positive electrode of a battery for a specified discharge rate.

Designing and obtaining improved battery materials is an extremely difficult task. Many different variables must be considered in designing an improved battery material, such as the application in which the battery functions, the stability/lifetime of the battery, cost, and the like. Traditionally, batteries have been designed to exhibit high energy density or high specific capacitance based on the desired application. This design choice has traditionally been attributed to the difficulties faced in eliminating and overcoming the various design variables that exist. Note that maximizing the energy density does not necessarily maximize the specific capacitance, and vice versa.

Regardless of how hard it is, it is extremely difficult to achieve a battery material that will enable high energy density and/or high specific capacitance. Despite some progress, there is still a need to continue to improve energy and/or specific capacitance, and many attempts have been made to this end. These attempts and subsequent results provide little guidance as to which combination of materials will achieve energy and further increase in capacitance.

It is generally expected that the Mn-rich phosphoric acid Li- is oxidized and reduced (about 4.0 V with respect to Li) in the olivine structure to be about 0.5 V higher than the redox potential of Fe (3.5 V vs. Li). Fe-Mn (LFMP) materials will achieve improved properties such as energy density and specific capacitance. In fact, others have focused on these Mn-rich phosphate materials. Surprisingly, and contrary to conventional wisdom, the present invention achieves improved properties (such as energy density and specific capacitance) of a positive electrode LFMP material having a lower content of Mn and, for example, Mn at The molar amount in LFMP is less than 60%, 55%, 50%, 45% or 40%.

Moreover, without wishing to be bound by theory, most doped metals have a stable oxidation state that can only be altered at a potential that is significantly different from the redox potential of Fe and/or Mn. Therefore, these doped metals are not expected to directly contribute to the electrical storage capacitance of the material. For example, since the redox potential of Co and Ni is at least about 0.5 V higher than the redox potential of manganese and at least 1.0 V higher than the redox potential of iron, such doped metals will generally not have significant electrical storage. The capacitor contributes to the battery operating at or near the redox plateau of Fe ²⁺ →Fe ³⁺ .

However, contrary to traditional wisdom, certain doping metals can help increase the energy density and/or specific capacitance of the battery.

In certain embodiments, the present invention provides a doped LFMP material having at least one olivine phase comprising lithium (Li), iron (Fe), manganese (Mn), one or more dopants ( D) and phosphate (PO ₄ ), wherein the total composition comprises Fe + Mn + D = 1.0, and the ratio of the amount of Li: (Fe + Mn + D) is from about 1.0 to about 1.05, and PO ₄ : (Fe + Mn + The ratio of the amount of D) is from about 1.0 to about 1.025, and D is one or more metals selected from the group consisting of cobalt (Co), nickel (Ni), vanadium (V), niobium (Nb), and The mixture, and the range of Mn is from 0.350 to less than 0.600, or from 0.400 to less than 0.600, or from 0.400 to 0.550, or from 0.450 to 0.550, or from 0.450 to 0.500. In certain embodiments, D is one or more metals selected from the group consisting of cobalt (Co), vanadium (V), or mixtures thereof. In certain embodiments, the positive electrode material may be more doped with fluorine (F).

In some embodiments, the composition comprises up to about 0.1 mole 1%, 0.5 mole%, 1 mole%, 1.5 mole%, 2 mole%, 2.5 mole%, 3 mole%, 3.5 moles %, 4 mole %, 4.5 mole %, 5 mole %, 6 moles %, 7 mole %, 8 mole %, 9 mole % or 10 mole % of the one or more dopant metals. In certain embodiments, the composition comprises up to 0.1 mol%, 0.5 mol%, 1 mol%, 1.5 mol%, 2 mol%, 2.5 mol%, 3 mol%, 3.5 mol% 4 mol%, 4.5 mol% or 5 mol% Co. In certain embodiments, the composition comprises up to 0.1 mol%, 0.5 mol%, 1 mol%, 1.5 mol%, 2 mol%, 2.5 mol%, 3 mol%, 3.5 mol% 4 mol%, 4.5 mol% or 5 mol% Ni. In certain embodiments, the composition comprises up to 0.1 mol%, 0.5 mol%, 1 mol%, 1.5 mol%, 2 mol%, 2.5 mol%, 3 mol%, 3.5 mol% , 4 mole %, 4.5 mole % or 5 mole % of V. In certain embodiments, the composition comprises up to 0.1 mol%, 0.5 mol%, 1 mol%, 1.5 mol%, 2 mol%, 2.5 mol%, 3 mol%, 3.5 mol% , 4 mole %, 4.5 mole % or 5 mole % F.

In one or more embodiments, a positive electrode material is provided that includes an electroactive material. The electroactive material includes at least an olivine phase, and the olivine phase includes lithium (Li), iron (Fe), manganese (Mn), one or more dopants (D), and phosphate (PO ₄ ), wherein The total composition has a ratio of Li:(Fe+Mn+D) of from about 1.000 to about 1.050, a ratio of (PO ₄ ):(Fe+Mn+D) of from about 1.000 to about 1.025, and D is selected from the following One or more of the constituent metals: cobalt (Co), nickel (Ni), vanadium (V), niobium (Nb), and mixtures thereof. In certain embodiments, D is one or more metals selected from the group consisting of cobalt (Co), vanadium (V), or mixtures thereof. In certain embodiments, the positive electrode material may be more doped with fluorine (F).

In one or more embodiments, a positive electrode material is provided comprising a lithium and/or phosphate stoichiometric electroactive material having one or more phases including lithium (Li), iron ( Fe), manganese (Mn), one or more dopants (D) and phosphate (PO ₄ ), wherein the total composition has a ratio of Li:(Fe+Mn+D) of about 1.000, about 1.000 (PO _{4 )} a ratio of (Fe + Mn + D), and D is one or more metals selected from the group consisting of cobalt (Co), nickel (Ni), vanadium (V), niobium (Nb) and mixture. In certain embodiments, D is one or more metals selected from the group consisting of cobalt (Co), vanadium (V), or mixtures thereof. In certain embodiments, D is one or more metals selected from the group consisting of cobalt (Co), vanadium (V), niobium (Nb), or mixtures thereof. Without wishing to be bound by theory, the presence of Nb may increase the conductivity of the electroactive material. In certain embodiments, the positive electrode material may be more doped with fluorine (F).

In one or more embodiments, a positive electrode material is provided that comprises a lithium-rich and/or phosphate-rich electroactive material. The electroactive material includes at least an olivine phase, and the olivine phase includes lithium (Li), iron (Fe), manganese (Mn), one or more dopants (D), and phosphate (PO ₄ ), wherein The total composition has a ratio of Li:(Fe+Mn+D) of from about 1.000 to about 1.050, a ratio of (PO ₄ ):(Fe+Mn+D) of from about 1.000 to about 1.025, and D is selected from the following One or more metals of each group consisting of cobalt (Co), nickel (Ni), vanadium (V), niobium (Nb), and mixtures thereof. In certain embodiments, D is one or more metals selected from the group consisting of cobalt (Co), vanadium (V), or mixtures thereof. In certain embodiments, the positive electrode material may be more doped with fluorine (F).

Excess lithium and excess phosphate in the total composition do not need to be monolithite The mono-olivine phase provides a non-stoichiometric olivine compound. Conversely, excess lithium and/or phosphate may be present, for example, in the form of a secondary phase in combination with olivine and the like.

Typically, a dopant such as Co, Ni, V, Nb, and/or F is doped into the lattice location of the olivine structure and resides at the lattice location of the olivine structure to form an olivine phase. However, a small amount of a dopant-rich secondary phase can be tolerated before exhibiting a degradation in Li-ion battery performance.

A cathodic electroactive material according to one or more embodiments exhibits a high energy density and/or a high specific capacitance at a high discharge rate, such as a rate corresponding to a complete discharge of the battery within one hour. 10 times faster (10C - meaning complete discharge occurs within six minutes or one tenth of an hour) and 20 times faster than the rate corresponding to a complete discharge of the battery within 1 hour (20C - meaning complete The discharge occurs within 3 minutes or within one-twentieth of an hour). For example, the positive electrode material achieves at least 200 mWh/g, 250 mWh/g, 300 mWh/g, 340 mWh/g, 350 mWh/g, 360 mWh/g or 370 mWh/g, 380 mWh/g, 390 mWh/ at a discharge rate of 20C. g or energy density of 400 mWh/g. In another aspect, the positive electrode material is provided wherein the specific capacitance is at least 90 mAh/g or 100 mAh/g or 110 mAh/g or 115 mAh/g or 120 mAh/g or 125 mAh/g at a discharge rate of 20C. The specific power density is at least 6,800 mW/g, 7,000 mW/g, 7,200 mW/g, 7,400 mW/g, 7600 mW/g, 7,800 mW/g or 8,000 mW/g at a discharge rate of 20C.

Please note that in order to make the lithium secondary battery a wide range of electric vehicles or large A large format energy grid application is widely accepted, and the battery must have a high energy storage density (Wh/kg) and a usable high power density (W/kg). Power density can simply be viewed as the energy capacity of a battery system that can be used (or stored) during a certain unit time. For example, in the particular materials described herein, the energy density (in mWh/g) is reported, where only the weight of the active cathode material is considered (rather than considering the total cell system weight), the report will contain the anode, current Selection of collectors, separators, electrolytes and packaging materials. In addition, we report the energy density at a significantly higher discharge rate of 20C (or 1/20, 180 seconds of 1 hour of complete energy loss). By focusing on this relatively high discharge rate, the reported materials not only meet energy density requirements but also high power density applications (like electrification of motor vehicles and instant energy grid stabilization).

Some suitable exemplary compositions that provide improved energy density and power density include, but are not limited to, Li _1.025 Mn _0.400 Fe _0.580 Co _0.020 (PO ₄ ) _1.000

Li _1.025 Mn _0.450 Fe _0.530 Co _0.020 (PO ₄ ) _1.000

Li _1.025 Mn _0.500 Fe _0.480 Co _0.010 Ni _0.010 (PO ₄ ) _1.000

Li _1.050 Mn _0.450 Fe _0.500 Co _0.010 Ni _0.010 V _0.030 (PO ₄ ) _1.025

Li _1.040 Mn _0.400 Fe _0.560 Co _0.010 Ni _0.010 V _0.020 (PO ₄ ) _1.015

Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.010 V _0.020 (PO ₄ ) _1.015

Li _1.030 Mn _0.450 Fe _0.520 Co _0.010 Ni _0.010 V _0.010 (PO ₄ ) _1.005

Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.010 V _0.030 (PO ₄ ) _1.010 F _0.015

Li _1.050 Mn _0.450 Fe _0.510 Co _0.0100 Ni _0.005 V _0.025 (PO ₄ ) _1.020

Li _1.000 Mn _0.500 Fe _0.460 Co _0.040 PO ₄

Li _1.000 Mn _0.450 Fe _0.530 Co _0.010 Ni _0.010 PO ₄

Li _1.025 Mn _0.500 Fe _0.480 Co _0.010 Nb _0.010 (PO ₄ ) _1.000

Li _1.050 Mn _0.450 Fe _0.500 Co _0.010 Nb _0.010 V _0.030 (PO ₄ ) _1.025

Li _1.040 Mn _0.400 Fe _0.560 Co _0.010 Nb _0.010 V _0.020 (PO ₄ ) _1.015

Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Nb _0.010 V _0.020 (PO ₄ ) _1.015

Li _1.030 Mn _0.450 Fe _0.520 Co _0.010 Nb _0.010 V _0.010 (PO ₄ ) _1.005

Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Nb _0.010 V _0.030 (PO ₄ ) _1.010 F _0.015 , or Li _1.050 Mn _0.450 Fe _0.510 Co _0.0100 Nb _0.005 V _0.025 (PO ₄ ) _1.020 .

In addition, controlling the size of the major olivine crystals to a size of <100 nm can be beneficial to enhance the lithium transport kinetics and conductivity of the LFMP materials of the present invention. Further details regarding the composition and preparation of such similar compounds (lithium phosphate-iron materials) are found in U.S. Published Application No. 2004/0005, 265, which is hereby incorporated by reference. Into this article.

Doping with a hypervalent transition metal such as Nb or V may be more beneficial to the advantageous application of the resulting olivine material to rechargeable lithium ion battery applications. The beneficial effect of the dopant can be several times and includes increased electron conductivity of the olivine powder and can limit the sintering of the olivine nanophosphate particles to allow for full utilization during rapid charge/discharge of the battery. Lithium capacitor.

Positively electroactive materials can be prepared in a number of different ways. In general, the process involves the preparation of sources containing lithium, iron, manganese and cobalt as well as additional doping metals. A mixture of starting materials from the source. An exemplary lithium source comprises lithium carbonate and lithium dihydrogen phosphate. Exemplary sources of iron include iron phosphate, ferrous oxalate, iron carbonate, and the like. Exemplary manganese sources include manganese carbonate and manganese phosphate. Exemplary dopant metal sources include cobalt oxalate, nickel oxalate, vanadium oxide, ammonium metavanadate, ammonium fluoride, and the like. The starting material can optionally be in hydrated form or used as a dry powder mixture. The starting material may optionally further comprise other components such as ammonium phosphate, a water soluble polymer (eg, a water-soluble vinyl-based copolymer), or other precursors (eg, a sugar precursor). ).

In certain embodiments, a positively-active material comprising a doped olivine electroactive compound can be prepared from a starting material of a lithium salt, an iron compound, and a phosphorus salt, including but not limited to, having used, for example, oxalic acid. Cobalt, nickel oxalate, vanadium oxide and/or ammonium fluoride to add additional low concentrations of doped metals (such as Co, Ni, V and/or F) to lithium carbonate, ferrous oxalate or iron carbonate, manganese carbonate and phosphoric acid Ammonium. The dried powder mixture is heated in a low oxygen (e.g., inert) environment at a temperature of from 300 ° C to 900 ° C and, for example, at a temperature of from about 600 ° C to 700 ° C. Further details regarding the compositions and preparations of such compounds are found in U.S. Published Application Nos. 2004/0005265, US 2009/01238134, and US 2009/0186277, each of which is incorporated herein in its entirety by reference.

In other embodiments, the process for the synthesis of lithium electroactive metal phosphates comprises milling and heating a mixture comprising materials of lithium source, iron phosphate, and one or more additional dopant metal sources under a reducing atmosphere. Exemplary starting materials include, but are not limited to, lithium carbonate, iron phosphate, and vanadium oxide. Heating the mixture under atmospheric pressure under a reducing atmosphere to about The temperature is from 550 ° C to 700 ° C, followed by cooling to room temperature, usually under an inert atmosphere. Further details regarding the compositions and preparation of such compounds are found in U.S. Patent No. 7,282,301, which is incorporated herein in its entirety by reference.

In other embodiments, the process for the synthesis of lithium electroactive metal phosphate comprises a water-based polishing process in which a starting material (such as lithium carbonate, hydrated iron phosphate, hydrated manganese phosphate, lithium dihydrogen phosphate, hydrated oxalic acid). Cobalt, hydrated nickel oxalate and ammonium metavanadate are mixed with a water-soluble vinyl-based copolymer or sugar precursor for grinding and subsequent drying. After drying, the powder can be heated at a desired temperature rise of up to about 700 ° C and then cooled to room temperature.

A positive electrode (cathode) is produced by applying a semi-liquid paste to both sides of a current collector foil or grid and drying the applied positive electrode composition, said semi-liquid paste containing homogeneously A cathode active compound and a conductive additive dispersed in a solution of a polymer binder in a suitable casting solvent. A metal substrate such as an aluminum foil or an expanded metal grid is used as the current collector. To improve adhesion of the active layer to the current collector, an adhesive layer (eg, a thin carbon polymer intercoating) can be applied. The dry lamination is extended to provide a layer having a uniform thickness and density. The binder used in the electrode may be any suitable binder used as a binder for the nonaqueous electrolyte battery.

In the process of assembling a lithium ion battery, the negative electrode active material may be any material capable of reversibly absorbing lithium. In an embodiment, the negative active material is a carbonaceous material. The carbonaceous material can be non-graphite or graphite. Small particle size, graphitized natural or synthetic carbon can be used as the negative active material. Although non-useable Graphite carbon material or graphite carbon material, but graphite materials such as natural graphite, spherical natural graphite, mesocarbon microbead, and carbon fiber (such as mesocarbon fiber) are preferably used.

A nonaqueous electrolyte is used, and the nonaqueous electrolyte contains a suitable lithium salt dissolved in a nonaqueous solvent. The electrolyte can be poured into a porous separator that separates the positive electrode from the negative electrode. In one or more embodiments, a microporous electrically insulating separator is used.

The positive electrode active material can be incorporated into any battery shape. In fact, a variety of different shapes and sizes can be used, such as a cylindrical (jelly roll), a square, a rectangular (prism) coin type, a button type, or the like.

Example 1: Stoichiometric LFMP material doped with cobalt

To prepare LiMn _x Fe _y Co _z PO ₄ (x+y+z=1), lithium carbonate, manganese carbonate, ferrous oxalate, cobalt oxalate and ammonium dihydrogen phosphate are contained in zirconia grinding media and acetone. The plastic grinding bottle was mixed for three days and then dried using a rotary evaporator.

Various samples were prepared in which the relative amounts of Mn, Fe and Co were changed as follows: 0.300 x 0.650, 0.300 y 0.680, and 0 z 0.100. The amount of the raw material is determined based on a metal test conducted by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) to provide each metal of the target mole % in the final product.

For example, to synthesize LiMn _0.500 Fe _0.460 Co _0.040 PO ₄ , 7.463 g of lithium carbonate, 12.08 g of manganese carbonate, 16.901 g of ferrous oxalate, 1.451 g of cobalt oxalate and 22.775 g of ammonium dihydrogen phosphate are contained. Mix 1000g of zirconia grinding media and 400ml of acetone in a plastic grinding bottle.

The dried powder was heated in a tube furnace under nitrogen. The heating profile was ramped from 25 ° C to 350 ° C in 5 hours, then held at 350 ° C for 5 hours, then climbed from 350 ° C to 700 ° C in 1 hour, then held at 700 ° C for 5 hours, It was then cooled to 25 °C. The finished product is ground and then stored in an anhydrous environment.

A positive electrode slurry by as Kynar ^® PVDF-HFP copolymer 2801 commercially available 0.0225g 1.496g dissolved in the acetone and the like prepared as hereinbefore described 0.1612g of LiMn _x Fe _y Co _z PO ₄ A dry mixture of (x+y+z=1) and 0.0204 g of conductive carbon (super P) was dispersed in the resulting solution to prepare. The paste was homogenized using a Wig-L-Bug casting in a vial on one side of the aluminum foil current collector using a die casting apparatus, dried at room temperature to remove the casting solvent, and then densified using a calendering device .

The positive electrode and the lithium foil as the negative electrode were cut to an appropriate size and a glass fiber separator (from Whatman) was inserted to form a half-cell of a Swagelok type against the lithium foil. The first charge capacity (FCC) and capacitance and energy were measured at the following rates: C/5, C/2, 1C, 2C, 5C, 10C, 20C, 35C, and 50C.

The results of various measurements are shown in Table 1 below:

1 is for having a LiMn positive electrodes _{x Fe y Co z PO 4 (} x + y + z = 1) active material and a negative battery lithium foil electrodes of LiMn _x Fe _y having various compositions of Co _z PO ₄ (x+y+z=1) Contour plot of specific energy at 20C rate. The boundary condition of the contour map is 0.300 x 0.650, 0.300 y 0.680 and 0 z 0.100. In the contour plot, the composition having the same Co content (z) is on a line parallel to the horizontal axis. The z value is indicated by the intersection of the lines on the vertical axis. For example, all compositions present on the horizontal dashed line in Figure 1 have the same Co content (z = 0.04). Compositions having the same Mn content (x) are located on a line oblique to the horizontal axis. The value of x is indicated by the intersection of the lines on the horizontal axis. For example, all of the compositions present on the slanted dashed line in Figure 1 have the same Mn content (x = 0.350).

The Co content (z) of the composition point in the contour map is the intersection of the horizontal line passing through the point and the vertical axis. The Mn content (x) of the composition point in the contour plot is the intersection of the line passing through the point parallel to the oblique dashed line (labeled Mn = 0.350) depicted in Figure 1 and the horizontal axis. When the Co and Mn contents were determined, the Fe content (y) of the composition point was determined from the equation x + y + z = 1.

Note that the LiMn _0.500 Fe _0.460 Co _0.040 PO ₄ composition exhibited the highest specific energy (334 mWh/g) at a discharge rate of 20C.

Example 2: Stoichiometric LFMP material doped with cobalt nickel

To prepare LiMn _x Fe _y Co _z/2 Ni _z/2 PO ₄ (x+y+z=1), of which 0.300 x 0.650, 0.300 y 0.630 and 0 z 0.120, lithium carbonate, manganese carbonate, ferrous oxalate, cobalt oxalate, nickel oxalate and ammonium dihydrogen phosphate were mixed in a plastic grinding flask containing zirconia grinding media and acetone for three days, and then dried using a rotary evaporator.

The amount of the raw material is determined based on a metal test by ICP-AES (Inductively Coupled Plasma Atomic Emission Spectrometer) to provide each metal of the target mole % in the final product. For example, to synthesize LiMn _0.450 Fe _0.530 Co _0.010 Ni _0.010 PO ₄ , 7.463 g of lithium carbonate, 10.843 g of manganese carbonate, 19.473 g of ferrous oxalate, 0.363 g of cobalt oxalate, 0.425 g of nickel oxalate and 22.775. The ammonium dihydrogen phosphate was mixed in a plastic grinding flask containing 1000 g of zirconia grinding medium and 400 ml of acetone.

The dried powder was heated in a tubular furnace under nitrogen. The heating curve was ramped from 25 ° C to 350 ° C in 5 hours, then held at 350 ° C for 5 hours, then climbed from 350 ° C to 700 ° C in 1 hour, then held at 700 ° C for 5 hours, then cooled to 25 °C. The finished product is ground and then stored in an anhydrous environment.

A positive electrode slurry by as Kynar ^® PVDF-HFP copolymer 2801 commercially available 0.0225g 1.496g dissolved in the acetone and the like prepared as hereinbefore described 0.1612g of LiMn _x Fe _y Co _{z / 2} A dry mixture of Ni _z/2 PO ₄ (x+y+z=1) and 0.0204 g of conductive carbon (super P) was dispersed in the resulting solution to prepare. The paste was homogenized using a Wig-L-Bug casting in a vial on one side of the aluminum foil current collector using a die casting apparatus, dried at room temperature to remove the casting solvent, and then densified using a calendering device .

The positive electrode and the lithium foil as the negative electrode are cut to an appropriate size and inserted with a glass fiber separator (from Whatman) to form a joint against the lithium foil Casing type half battery. The first charging capacitor (FCC) and the capacitance and energy are measured at the following rates: C/5, C/2, 1C, 2C, 5C, 10C, 20C, 35C, and 50C.

The results of various measurements are shown in Table 2 below:

2 is a LiMn having various compositions for a battery having a LiMn _x Fe _y Co _z/2 Ni _z/2 PO ₄ (x+y+z=1) active material as a positive electrode and a lithium foil as a negative electrode _x Fe _y Co _z/2 Ni _z/2 PO ₄ (x+y+z=1) is a contour plot of specific energy at a 20C rate. The boundary condition of the contour map is 0.300 x 0.650, 0.300 y 0.630 and 0 z 0.120. The cobalt content is the same as the nickel content, each indicated by z/2. In the contour plot, the composition having the same "Co plus Ni" content (z) is located on a line parallel to the horizontal axis. The z value is indicated by the intersection of the lines on the vertical axis. For example, all of the compositions present on the horizontal dashed line in Figure 2 have the same "Co plus Ni" content (z = 0.040) and the Co and Ni contents are each 0.020. Compositions having the same Mn content (x) are located on a line oblique to the horizontal axis. The value of x is indicated by the intersection of the lines on the horizontal axis. For example, all of the compositions present on the slanted dashed line in Figure 2 have the same Mn content (x = 0.350).

The "Co plus Ni" content (z) of the composition point in the contour map is the intersection of the horizontal line passing through the point and the vertical axis. The Mn content (x) of the composition point in the contour map is the oblique imaginary of the point passing through the point The line (marked as Mn = 0.350) is the intersection of the parallel line and the horizontal axis. When "Co plus Ni" and Mn content were determined, the Fe content (y) of the composition point was determined from the equation x + y + z = 1.

Note that the composition of LiMn _0.450 Fe _0.530 Co _0.010 Ni _0.010 PO ₄ exhibited the highest specific energy (318 mWh/g) at a discharge rate of 20C.

Example 3: Non-stoichiometric LFMP material doped with cobalt

Additional improvements were observed in the preparation of lithium-rich LFMP materials doped with cobalt. During this study, 2.5 mol% excess Li was used, and the amounts of Mn, Fe, and Co were variable, as represented by Li _1.025 Mn _x Fe _y Co _z PO ₄ , where 0.35 x 0.65, x+y+z=1 and 0.00 z 0.08.

To prepare Co-doped LFMP, Li ₂ CO ₃ , FePO ₄ .xH ₂ O, Mn ₃ (PO ₄ ) ₂ .H ₂ O, LiH ₂ PO ₄ , CoC ₂ O ₄ .2H ₂ O and soluble The vinyl-based copolymer precursor of alcohol was mixed in a plastic grinding bottle containing YTZ zirconia grinding media and IPA for three days and then dried using a rotary evaporator. The material is selected based on the metal assay in the analytical certificate provided by the manufacturer to provide each metal of the target mole % in the final product.

For example, to prepare 0.1M ( 16G) The _{Li 1.025 Mn 0.450 Fe 0.530 Co 0.020} PO 4, Li 3.265g use of ₂ CO _{3, 10.242g} of FePO ₄ .xH ₂ O, 6.267g of _{Mn 3 (PO 4) 2 .xH} 2 O, 1.576g LiH ₂ PO ₄ , 0.366 g of CoC ₂ O ₄ .2H ₂ O and 0.947 g of an alcohol-based vinyl-based copolymer.

Heated and dried in a tubular furnace under an inert atmosphere by a temperature programmed reaction (TPR) method. powder. The heating curve was ramped from 25 ° C to 350 ° C in 0.5 hours, then held at 350 ° C for 0.5 hours, then climbed from 350 ° C to 700 ° C in 0.5 hours, then held at 700 ° C for 1 hour, then cooled to 25 °C. The finished product is ground and then stored in an anhydrous environment.

The positive electrode slurry is from AtoFina by as Kynar ^® PVDF-HFP copolymer 2801 commercially available 0.0225g 1.496g dissolved in the acetone and the like as hereinbefore described is prepared with 0.0204 0.1612g of doping LFMP A dry mixture of conductive carbon (super P or Ensaco) of g is dispersed in the resulting solution to prepare. The paste was homogenized using a Wig-L-Bug casting in a vial on one side of the aluminum foil current collector using a die casting apparatus, dried in an oven to remove the casting solvent, and densified using a calendering apparatus.

The positive electrode and the lithium foil as the negative electrode were cut into a half-cell of a suitable size and inserted with a glass fiber separator to form a joint sleeve type against the lithium foil. The first charging capacitor (FCC) and the capacitance and energy are measured at the following rates: C/5, C/2, 1C, 2C, 5C, 10C, 20C, 30C, and 50C.

The results of various measurements are shown in Table 3 below:

3 is a line graph of 20 C discharge energy versus Mn content and dopant (Co) content for a battery including various samples of Example 3 as a positive electrode and a lithium foil as a negative electrode.

Note that the highest 20C energy performance composition from Figure 3 is Li _1.025 Mn _0.400 Fe _0.580 Co _0.020 PO ₄ (382 mWh/g).

Example 4: Non-stoichiometric LFMP material doped with cobalt and nickel

Additional improvements were observed in the preparation of lithium-rich LFMP materials doped with cobalt and nickel. During this study, 2.5 mol% excess Li was used, and the amounts of Mn, Fe, Co, and Ni were variable, as represented by Li _1.025 Mn _x Fe _y Co _z Ni _z PO ₄ , where 0.350 x 0.650, x+y+2z=1 and 0.00 z 0.035.

To prepare LMFP doped with Co and Ni, Li ₂ CO ₃ , FePO ₄ .xH ₂ O, Mn ₃ (PO ₄ ) ₂ .H ₂ O, LiH ₂ PO ₄ , CoC ₂ O ₄ .2H ₂ O, NiC ₂ O ₄ .2H ₂ O and an alcohol-soluble vinyl-based copolymer precursor were mixed in a plastic grinding bottle containing YTZ zirconia grinding media and IPA for three days, and then dried using a rotary evaporator. The material is selected based on the metal assay in the analytical certificate provided by the manufacturer to provide each metal of the target mole % in the final product.

For example, to prepare 0.1M ( 16 g) of Li _1.025 Mn _0.500 Fe _0.480 Co _0.010 Ni _0.010 PO ₄ , using 3.195 g of Li ₂ CO ₃ , 9.276 g of FePO ₄ .xH ₂ O, 6.963 g of Mn ₃ (PO ₄ ) ₂ .xH ₂ O, 1.774 g of LiH ₂ PO ₄ , 0.183 g of CoC ₂ O ₄ .2H ₂ O, 0.183 g of NiC ₂ O ₄ .2H ₂ O and 0.947 g of an alcohol-soluble vinyl-based copolymer.

The dried powder was heated in a tubular furnace under a inert atmosphere using a TPR (twin temperature reaction) method. The heating curve was ramped from 25 ° C to 350 ° C in 0.5 hours, then held at 350 ° C for 0.5 hours, then climbed from 350 ° C to 700 ° C in 0.5 hours, then held at 700 ° C for 1 hour, then cooled to 25 °C. The finished product is ground and then stored in an anhydrous environment.

The positive electrode slurry is from AtoFina by as Kynar ^® PVDF-HFP copolymer 2801 commercially available 0.0225g 1.496g dissolved in the acetone and the like as hereinbefore described is prepared with 0.0204 0.1612g of doping LFMP A dry mixture of conductive carbon (super P or Ensaco) of g is dispersed in the resulting solution to prepare. The paste was homogenized using a Wig-L-Bug casting in a vial on one side of the aluminum foil current collector using a die casting apparatus, dried in an oven to remove the casting solvent, and densified using a calendering apparatus.

The positive electrode and the lithium foil as the negative electrode were cut to an appropriate size and a glass fiber separator was inserted to form a jointed sleeve type half cell against the lithium foil. The first charging capacitor (FCC) and the capacitance and energy are measured at the following rates: C/5, C/2, 1C, 2C, 5C, 10C, 20C, 30C, and 50C.

The results of various measurements are shown in Table 4 below:

4 is a line graph of 20 C discharge energy versus Mn content and dopant (Co+Ni) content for a battery including various samples of Example 4 as a positive electrode and a lithium foil as a negative electrode.

Note that the highest 20C energy performance composition from Figure 4 is Li _1.025 Mn _0.500 Fe _0.480 Co _0.010 Ni _0.010 PO ₄ (415 mWh/g).

Example 5: Non-stoichiometric LFMP material doped with cobalt, nickel and vanadium

Additional improvements were observed in the preparation of lithium-rich LFMP materials doped with cobalt, nickel and vanadium. Explore the parameter space of five different groups.

In Group A, 5 mole % excess Li and 2.5 mole % excess PO _{4 were used} , doped with 3 mole % of V. The amount of Mn, Fe, Co, and Ni is variable, as represented by Li _1.050 Mn _x Fe _y Co _z Ni _z V _0.03 (PO ₄ ) _1.025 , of which 0.350 x 0.650, x+y+2z=0.970 and 0.00 z 0.035.

In group B, the sample is represented by Li _1.040 Mn _x Fe _y Co _z Ni _z V _0.020 (PO ₄ ) _1.015 , of which 0.400 x 0.600, x+y+2z=0.980 and 0.00 z 0.0350.

In group C, the sample is represented by Li _1.030 Mn _x Fe _y Co _z Ni _z V _0.010 (PO ₄ ) _1.005 , of which 0.400 x 0.600, x+y+2z=0.990 and 0.00 z 0.035.

In group D, the sample is represented by Li _1.020+z Mn _x Fe _y Co _0.010 Ni _0.010 V _z (PO ₄ ) _0.995+z , where x=0.450, x+y+z=0.980 and 0.00 z 0.050.

In group E, the sample is represented by Li _1.040 Mn _x Fe _y Co _z Ni _w V _0.020 (PO ₄ ) _1.015 , where x = 0.45, x + y + z + w = 0.98, 0.00 z 0.030 and 0.00 w 0.030.

To prepare the Co, Ni and V doped LFMP materials indicated in Groups A through E, Li ₂ CO ₃ , FePO ₄ .xH ₂ O, Mn ₃ (PO ₄ ) ₂ .H ₂ O, LiH ₂ PO _{4 , CoC 2 O 4 .2H 2 O} , NiC 2 O 4 .2H 2 O, V 2 O 5 and based on the alcohol-soluble plastic bottle containing YTZ milling zirconia grinding media and IPA precursors of the vinyl copolymer Mix in for three days and then use a rotary evaporator to dry. The material is selected based on the metal assay in the analytical certificate provided by the manufacturer to provide each metal of the target mole % in the final product.

For example, to prepare 0.1M ( 16g) Li _1.050 Mn _0.450 Fe _0.500 Co _0.010 Ni _0.010 V _0.030 (PO ₄ ) _1.025 , using 3.149 g of Li ₂ CO ₃ , 9.663 g of FePO ₄ .xH ₂ O, 6.267 g of Mn ₃ (PO ₄ ) ₂ .xH ₂ O, LiH 2.166g of ₂ PO CoC _4, 0.183g of ₂ O ₄ .2H ₂ O, 0.183g of _{NiC 2 O 4 .2H 2 O,} 0.273g of V ₂ O ₅ and 0.947g of soluble A vinyl-based copolymer of alcohol.

The dried powder was heated in a tubular furnace under a inert atmosphere using a TPR (twin temperature reaction) method. The heating curve was ramped from 25 ° C to 350 ° C in 0.5 hours, then held at 350 ° C for 0.5 hours, then climbed from 350 ° C to 700 ° C in 0.5 hours, then held at 700 ° C for 1 hour, then cooled to 25 °C. The finished product is ground and then stored in an anhydrous environment.

The positive electrode slurry is from AtoFina by as Kynar ^® PVDF-HFP copolymer 2801 commercially available 0.0225g 1.496g dissolved in the acetone and the like as hereinbefore described is prepared with 0.0204 0.1612g of doping LFMP A dry mixture of conductive carbon (super P or Ensaco) of g is dispersed in the resulting solution to prepare. The paste was homogenized using a Wig-L-Bug casting in a vial on one side of the aluminum foil current collector using a die casting apparatus, dried in an oven to remove the casting solvent, and densified using a calendering apparatus.

The positive electrode and the lithium foil as the negative electrode were cut into a half-cell of a suitable size and inserted with a glass fiber separator to form a joint sleeve type against the lithium foil. The first charging capacitor (FCC) and the capacitance and energy are measured at the following rates: C/5, C/2, 1C, 2C, 5C, 10C, 20C, 30C, and 50C.

The results of various measurements from Group A are shown in Table 5A below: Table 5A

5A is a line graph of 20 C discharge energy versus Mn content and dopant (Co+Ni+V) content for a battery including various samples of group A as a positive electrode and a lithium foil as a negative electrode.

Note that the highest 20C energy performance composition from Table 5A is Li _1.050 Mn _0.450 Fe _0.500 Co _0.010 Ni _0.010 V _0.030 (PO ₄ ) _1.025 (424 mWh/g).

The results of various measurements from Group B are shown in Table 5B below:

5B is a line graph of 20 C discharge energy versus Mn content and dopant (Co+Ni+V) content for a battery including various samples of group B as a positive electrode and a lithium foil as a negative electrode.

Note that the highest 20C energy performance composition from Table 5B is Li _1.040 Mn _0.400 Fe _0.560 Co _0.010 Ni _0.010 V _0.020 (PO ₄ ) _1.015 (426 mWh/g) and Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.010 V _0.020 ( PO ₄ ) _1.015 (425 mWh/g).

The results of various measurements from Group C are shown in Table 5C below:

5C is a line graph of 20 C discharge energy versus Mn content and dopant (Co+Ni+V) content for a battery including a plurality of samples of the group C as a positive electrode and a lithium foil as a negative electrode.

Note that the highest 20C energy performance composition from Table 5C is Li _1.030 Mn _0.450 Fe _0.520 Co _0.010 Ni _0.010 V _0.010 (PO ₄ ) _1.005 (386 mWh/g).

The results of various measurements from Group D are shown in Table 5D below:

Note that the highest 20C energy performance composition from Table 5D is Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.010 V _0.020 (PO ₄ ) _1.015 (425 mWh/g) and Li _1.050 Mn _0.450 Fe _0.500 Co _0.010 Ni _0.010 V _0.030 ( PO ₄ ) _1.025 (424 mWh/g).

The results of various measurements from Group E are shown in Table 5E below:

Note that the highest 20C energy performance composition from Table 5E is Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.010 V _0.020 (PO ₄ ) _1.015 (425 mWh/g).

Thus, in Example 5, Groups A, B, D, and E demonstrate the use of Co, Ni, and V doped LFMP materials (eg, Li _1.050 Mn _0.450 Fe _0.500 Co _0.010 Ni _0.010 V _0.030 (PO ₄ ) _1.025 and Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.010 V _0.020 (PO ₄ ) _1.015 ) An energy density of up to about 425 mWh/g can be achieved.

Example 6: Non-stoichiometric LFMP material doped with cobalt, nickel, vanadium and fluorine

Additional improvements were observed in the preparation of lithium-rich LFMP materials doped with cobalt, nickel, vanadium and fluorine. During this study, a material represented by Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.010 V _0.020 (PO ₄ ) _1.015-x/3 F _{x was prepared} , of which 0.00 x 0.060.

To prepare the Co, Ni, V and F doped LFMP materials indicated above, Li ₂ CO ₃ , FePO ₄ .xH ₂ O, Mn ₃ (PO ₄ ) ₂ .H ₂ O, LiH ₂ PO ₄ , CoC _{2 O 4 .2H 2 O, NiC} 2 O 4 .2H 2 O, NH 4 F and alcohol-soluble copolymer of vinyl-based precursor in the mixing flask containing YTZ milling zirconia grinding media and the plastic of three IPA Days, and then use a rotary evaporator to dry. The material is selected based on the metal assay in the analytical certificate provided by the manufacturer to provide each metal of the target mole % in the final product.

For example, to prepare 0.1M ( 16g) Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.010 V _0.020 (PO ₄ ) _1.010 F _0.015 , using 3.266 g of Li ₂ CO ₃ , 9.856 g of FePO ₄ .xH ₂ O, 6.267 g of Mn ₃ (PO _{4 2} .xH ₂ O, 1.732 g of LiH ₂ PO ₄ , 0.170 g of NH ₄ CoPO ₄ , 0.238 g of Ni ₃ (PO ₄ ) ₂ .xH ₂ O, 0.182 g of V ₂ O ₅ , 0.069 g of NH ₄ F and 0.947 g of a vinyl-based copolymer soluble in alcohol.

The dried powder was heated in a tubular furnace under a inert atmosphere using a TPR (twin temperature reaction) method. The heating curve was ramped from 25 ° C to 350 ° C in 0.5 hours, then held at 350 ° C for 0.5 hours, then climbed from 350 ° C to 700 ° C in 0.5 hours, then held at 700 ° C for 1 hour, then cooled to 25 °C. The finished product is ground and then stored in an anhydrous environment.

The positive electrode slurry is from AtoFina by as Kynar ^® PVDF-HFP copolymer 2801 commercially available 0.0225g 1.496g dissolved in the acetone and the like as hereinbefore described is prepared with 0.0204 0.1612g of doping LFMP A dry mixture of conductive carbon (super P or Ensaco) of g is dispersed in the resulting solution to prepare. The paste was homogenized using a Wig-L-Bug casting in a vial on one side of the aluminum foil current collector using a die casting apparatus, dried in an oven to remove the casting solvent, and densified using a calendering apparatus.

The positive electrode and the lithium foil as the negative electrode were cut into a half-cell of a suitable size and inserted with a glass fiber separator to form a joint sleeve type against the lithium foil. The first charging capacitor (FCC) and the capacitance and energy are measured at the following rates: C/5, C/2, 1C, 2C, 5C, 10C, 20C, 30C, and 50C.

Results of various measurements from Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.010 V _0.030 (PO ₄ ) _1.010 F _0.015 and Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.010 V _0.020 (PO ₄ ) _1.015 from Example 5 above Shown in Table 6 below:

As shown, Li ₂₀₄₀ Mn _0.450 Fe _0.510 Co _0.010 Ni _0.010 V _0.030 (PO ₄ ) _1.010 F _0.015 (453 mWh/g) 20C energy efficiency ratio for Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.010 V _0.020 (PO _{4 1.015} (425 mWh/g) The 20C energy performance observed in Example 5 was about 6.7%.

Example 7: Li _I.030 Fe _0.970 V _0.030 PO ₄ With Li _1.050 Mn _0.450 Fe _0.500 Co _0.010 Ni _0.010 V _0.030 (PO ₄ ) _1.025 Comparison

The energy density of Li _1.03 Fe _0.97 V _0.03 PO ₄ (which can be found in Example 2 of US 2009/0186277) was compared to the energy density of Li _1.050 Mn _0.450 Fe _0.500 Co _0.010 Ni _0.010 V _0.030 (PO ₄ ) _1.025 . As shown in Tables 7 and 6 below, there is a substantial increase in energy density at all discharge rates. For example, Li _1.050 Mn _0.450 Fe _0.500 Co _0.010 Ni _0.010 V _0.030 (PO ₄ ) _1.025 composition (identified as "Co-Ni-V M1x" in Table 7 and "Co-Ni-V LMFP in Fig. 6"M1x") can achieve about 424 mWh/g at 20 C, while Li _1.030 Fe _0.970 V _0.030 PO ₄ composition (identified as "V M1" in Table 7 and "V LFP M1" in Fig. 6) shows 331 mWh/ g.

Experiment 8: Elemental analysis with STEM

Use an X-ray detector equipped with an Oxford instrument and use it for x-ray micro The JEOL 2010 EEG TEM of the INCA analyzer of the quantitative analysis performed elemental analysis of various Co and Ni doped LFMP nanoparticles by scanning transmission electron microscopy (STEM).

7 is a STEM image of a sample of sample CX8-086 (Li _1.050 Mn _0.450 Fe _0.500 Co _0.010 Ni _0.010 V _0.030 (PO ₄ ) _1.025 ), and FIG. 8, FIG. 9, FIG. 10, FIG. Corresponding energy dispersive X-ray (EDX) surface distribution maps of Fe, Mn, Co, Ni and V are respectively shown. Fe, Mn, Co, and V appear to be uniformly dispersed on all particles. However, some areas are enriched in Ni, indicating the presence of a Ni-rich secondary phase. High resolution X-ray energy spectrum analysis also confirmed the presence of a Ni-rich region. A similar result was obtained from the sample CX8-071 (Li _1.025 Mn _0.450 Fe _0.530 Co _0.010 Ni _0.010 PO ₄ ), that is, Fe, Mn, Co were uniformly dispersed on all the particles and a Ni-rich region was present. For the sample CX8-067 (Li _1.025 Mn _0.450 Fe _0.510 Co _0.040 PO ₄ ), Fe and Mn were uniformly dispersed on all the particles, but some regions were enriched in Co, indicating the presence of a Co-rich secondary phase. High-resolution X-ray energy spectrum analysis also confirmed the presence of the Co-rich region in the CX8-067 sample.

The results indicate that Co is present in the olivine structure in the form of a solid solution with a solubility greater than 1 mol% but less than 4 mol%. Ni is slightly less soluble than Co and has a solubility of less than 1 mol%.

Without wishing to be bound by theory, it was observed that the sample exhibiting the highest energy density exists in the form of a solid solution, while the secondary phase rich in Co and Ni-rich is found in samples exhibiting lower energy density.

Example 9: Water-based non-stoichiometric LFMP material doped with cobalt, nickel and vanadium

The water-based LFMP material synthesis route is environmentally friendly and has the additional advantage of lower cost. Lithium-rich LFMP materials doped with cobalt, nickel and vanadium are also synthesized by a water-based polishing process. Similar capacitance and energy performance were observed for LFMP materials synthesized by a water based grinding process as compared to the results discussed above.

The formulation of the LFMP material synthesized by the water-based polishing process was Li _1.050 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.005 V _0.025 (PO ₄ ) _1.020 .

To prepare water-based Co, Ni and V doped LFMP materials, Li ₂ CO ₃ , FePO ₄ .xH ₂ O, Mn ₃ (PO ₄ ) ₂ .H ₂ O, LiH ₂ PO ₄ , CoC ₂ O _{4 .2H 2 O, NiC 2 O 4} .2H 2 O, NH 4 VO 3, water-soluble vinyl-based copolymers or sugar precursor, and water with a Silverson mixer at 5,000RPM mixing up the plastic bottle For 30 minutes, the water slurry was then ground in a MicroCer HEM (High Energy Mill) at 3,000 RPM for 30 minutes. The slurry was spray dried into a powder by a B-290 Mini Spray Dryer.

The material is selected based on the metal assay in the analytical certificate provided by the manufacturer to provide each metal of the target mole % in the final product. For example, to prepare 0.5M ( 80 g) of Li _1.050 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.005 V _0.025 (PO ₄ ) _1.020 using 16.034 g of Li ₂ CO ₃ , 49.245 g of FePO ₄ .xH ₂ O, 31.318 g of Mn ₃ (PO ₄ ) ₂ .xH ₂ O, 10.015 g of LiH ₂ PO ₄ , 0.915 g of CoC ₂ O ₄ .2H ₂ O, 0.457 g of NiC ₂ O ₄ .2H ₂ O, 1.462 g of NH ₄ VO ₃ and 7.099 g of sugar.

The dried powder was heated in a tubular furnace under a inert atmosphere using a TPR (twin temperature reaction) method. The heating curve was ramped from 25 ° C to 350 ° C in 0.5 hours, then held at 350 ° C for 0.5 hours, then climbed from 350 ° C to 700 ° C in 0.5 hours, then held at 700 ° C for 1 hour, then cooled to 25 °C. The finished product is ground and then stored in an anhydrous environment.

The positive electrode slurry is from AtoFina by as Kynar ^® PVDF-HFP copolymer 2801 commercially available 0.0225g 1.496g dissolved in the acetone and the like as hereinbefore described is prepared with 0.0204 0.1612g of doping LFMP A dry mixture of conductive carbon (super P or Ensaco) of g is dispersed in the resulting solution to prepare. The paste was homogenized using a Wig-L-Bug casting in a vial on one side of the aluminum foil current collector using a die casting apparatus, dried in an oven to remove the casting solvent, and densified using a calendering apparatus.

The positive electrode and the lithium foil as the negative electrode were cut into a half-cell of a suitable size and inserted with a glass fiber separator to form a joint sleeve type against the lithium foil. The first charging capacitor (FCC) and the capacitance and energy are measured at the following rates: C/5, C/2, 1C, 2C, 5C, 10C, 20C, 30C, and 50C.

Li _1.050 Mn _0.45 Fe _0.51 Co _0.010 Ni _0.005 V _0.025 (PO ₄ ) _{1.020 was} also prepared according to the procedure described in Example 6 (i.e., using IPA). The results of various measurements from water-based and IPA-based LFMP materials are shown in Table 8 below:

Note that the capacitance and energy performance of water-based LFMP materials is very similar to the capacitance and energy performance of IPA-based LFMP materials, and the 20C discharge energy of water-based LFMP materials is 423 mWh/g.

After reviewing the above description and examples, those skilled in the art will understand that modifications and equivalent substitutions can be made in the practice of the invention without departing from the spirit of the invention. Therefore, the present invention is not intended to be limited by the embodiments specifically described above.

The present invention will be more fully understood and appreciated by the description of the appended claims. Where: Figure 1 is a contour plot of energy density as a function of a composition of a stoichiometric LFMP material doped with Co, wherein the vertical axis indicates the Co content of the composition LiMn _x Fe _y Co _z PO ₄ and the horizontal axis indicates Mn Content; and wherein the Co content (z) of the composition point LiMn _x Fe _y Co _z PO ₄ in the contour map is the intersection of the horizontal line passing through the point and the vertical axis; the Mn content of the composition point in the contour map ( x) is the intersection of the line passing through the point parallel to the oblique dashed line (labeled Mn=0.350) depicted in the figure, and the horizontal axis; and the Fe content (y) of the composition point is borrowed It is determined by satisfying the equation x+y+z=1.

2 is a contour plot of energy density as a function of a composition of a stoichiometric LFMP material doped with Co and Ni, wherein the vertical axis indicates the Co addition of the composition LiMn _x Fe _y Co _z/2 Ni _z/2 PO ₄ The content of Ni, and the horizontal axis indicates the Mn content; and the content of the Co plus Ni (z) of the composition point LiMn _x Fe _y Co _z/2 Ni _z/2 PO ₄ in the contour map is through the point The intersection of the horizontal line and the vertical axis; the Mn content (x) of the composition point in the contour map is a line passing through the point parallel to the oblique dotted line (labeled Mn=0.350) depicted in the figure. The intersection of the horizontal axes; and the Fe content (y) of the composition point is determined by satisfying the equation x+y+z=1.

Figure 3 is a contour plot of energy density as a function of Co dopant content and Mn content in a non-stoichiometric LFMP material doped with Co.

4 is a contour plot of energy density as a function of Co, Ni dopant content, and Mn content in a non-stoichiometric LFMP material doped with Co and/or Ni.

5A is a contour plot of energy density as a function of Co, Ni dopant content, and Mn content in a non-stoichiometric LFMP material doped with Co, Ni, and/or V, wherein V is constant at 0.030 and Co, Ni is variable.

Figure 5B is a non-chemical energy density with Co, Ni and/or V doped A contour plot of the Co, Ni dopant content and Mn content in the LFMP material, wherein V is kept constant at 0.020 and Co, Ni is variable.

5C is a contour plot of energy density as a function of Co, Ni dopant content, and Mn content in a non-stoichiometric LFMP material doped with Co, Ni, and/or V, where V is constant at 0.010 and Co, Ni is variable.

Figure 6 is a graph comparing specific energy as a function of C rate for Li _1.030 Fe _0.970 V _0.030 PO ₄ and Li _1.050 Mn _0.450 Fe _0.500 Co _0.010 Ni _0.010 V _0.030 (PO ₄ ) _1.025 .

7 is a STEM image of a nanoparticle having a sample of Mn 45%, Fe 50%, Co 1%, Ni 1%, V3%.

8 is a graph showing the corresponding energy dispersive X-ray (EDX) mapping of the sample of FIG. 7 with respect to Fe.

Figure 9 is a graph showing the corresponding energy dispersive X-ray (EDX) surface distribution of Mn of the sample of Figure 7.

Figure 10 is a graph showing the corresponding energy dispersive X-ray (EDX) surface distribution of Co of the sample of Figure 7.

Figure 11 is a graph showing the corresponding energy dispersive X-ray (EDX) surface distribution of Ni of the sample of Figure 7.

Figure 12 is a diagram showing the corresponding energy dispersive X-ray (EDX) surface distribution of V for the sample of Figure 7.

Claims (27)

A positive electrode material comprising: an electroactive material having a total composition comprising: lithium (Li), iron (Fe), manganese (Mn), one or more dopants (D), and phosphate (PO) ₄ ), wherein the amount of Fe + Mn + D is 1.0; the ratio of the amount of Li: (Fe + Mn + D) is greater than 1.0 to 1.05; the ratio of the amount of PO ₄ : (Fe + Mn + D) is greater than 1.0 To 1.025; D is one or more dopants selected from the group consisting of cobalt (Co), nickel (Ni), vanadium (V), and niobium (Nb); the amount of Mn is 0.35 to 0.60; The amount of D is 0.001 to 0.10; and the electroactive material includes at least one phase having an olivine structure including the Li, the Fe, the Mn, the D, and the phosphate And wherein the combination of the excess lithium and the amount of Mn has an energy density of at least 250 mWh/g and a specific capacitance of at least 100 mAh/g at a 20 C discharge rate during operation of the positive electrode material in the cell. The positive electrode material of claim 1, wherein the positive electrode material provides an energy density of at least 340 mWh/g at a 20 C discharge rate during operation in the battery. The positive electrode material of claim 1, wherein the electroactive material further comprises fluorine substituted at a phosphate lattice position. The positive electrode material as described in claim 1 of the patent scope, wherein D Includes Co in an amount up to 0.05. The positive electrode material of claim 1, wherein D comprises Co in an amount of up to 0.03. The positive electrode material of claim 1, wherein D comprises Co in an amount of up to 0.05 and Ni in an amount of up to 0.035. The positive electrode material of claim 1, wherein D comprises Co in an amount of up to 0.02 and Ni in an amount of up to 0.02. The positive electrode material of claim 1, wherein D comprises Co in an amount of up to 0.05, Ni in an amount of up to 0.035, and V in an amount of up to 0.05. The positive electrode material of claim 1, wherein D comprises Co in an amount of up to 0.02, Ni in an amount of up to 0.02, and V in an amount of up to 0.04. The positive electrode material of claim 1, wherein the electroactive material comprises Co in an amount of up to 0.05, Ni in an amount of up to 0.035, V in an amount of up to 0.05, and F in an amount of up to 0.06. The positive electrode material of claim 1, wherein the electroactive material comprises Co in an amount of up to 0.02, Ni in an amount of up to 0.02, V in an amount of up to 0.04, and F in an amount of up to 0.025. The positive electrode material according to claim 1, wherein the electroactive material is one or more electroactive materials selected from the group consisting of Li _1.050 Mn _0.450 Fe _0.500 Co _0.010 Ni _0.010 V _0.030 ( PO ₄ ) _1.025 , Li _1.040 Mn _0.400 Fe _0.560 Co _0.010 Ni _0.010 V _0.020 (PO ₄ ) _1.015 , Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.010 V _0.020 (PO ₄ ) _1.015 , Li _1.030 Mn _0.450 Fe _0.520 Co _0.010 Ni _0.010 V _0.010 (PO ₄ ) _1.005 , Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.010 V _0.030 (PO ₄ ) _1.010 F _0.015 , Li _1.050 Mn _0.450 Fe _0.510 Co _0.0100 Ni _0.005 V _0.025 (PO ₄ ) _1.020 , Li _1.050 Mn _0.450 Fe _0.500 Co _0.010 Nb _0.010 V _0.030 (PO ₄ ) _1.025 , Li _1.040 Mn _0.400 Fe _0.560 Co _0.010 Nb _0.010 V _0.020 (PO ₄ ) _1.015 , Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Nb _0.010 V _0.020 (PO ₄ ) _1.015 Li _1.030 Mn _0.450 Fe _0.520 Co _0.010 Nb _0.010 V _0.010 (PO ₄ ) _1.005 , Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Nb _0.010 V _0.030 (PO ₄ ) _1.010 F _0.015 , and Li _1.050 Mn _0.450 Fe _0.510 Co _0.0100 Nb _0.005 V _0.025 ( PO ₄ ) _1.020 . The positive electrode material according to claim 1, wherein the positive electrode material is one or more electroactive materials selected from the group consisting of Li _1.050 Mn _0.450 Fe _0.500 Co _0.010 Ni _0.010 V _0.030 ( PO ₄ ) _1.025 , Li _1.040 Mn _0.400 Fe _0.560 Co _0.010 Ni _0.010 V _0.020 (PO ₄ ) _1.015 , Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.010 V _0.020 (PO ₄ ) _1.015 , Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.010 V _0.030 (PO ₄ ) _1.010 F _0.015 , Li _1.050 Mn _0.450 Fe _0.510 Co _0.010 Ni _0.005 V _0.025 (PO ₄ ) _1.020 , Li _1.050 Mn _0.450 Fe _0.500 Co _0.010 Nb _0.010 V _0.030 (PO ₄ ) _1.025 , Li _1.040 Mn _0.400 Fe _0.560 Co _0.010 Nb _0.010 V _0.020 (PO ₄ ) _1.015 , Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Nb _0.010 V _0.020 (PO ₄ ) _1.015 , Li _1.040 Mn _0.450 Fe _0.510 Co _0.010 Nb _0.010 V _0.030 (PO ₄ ) _1.010 F _0.015 , and Li _1.050 Mn _0.450 Fe _0.510 Co _0.010 Nb _0.005 V _0.025 (PO ₄ ) _1.020 . The positive electrode material of claim 1, wherein the positive electrode material consists essentially of an olivine phase. The positive electrode material of claim 1, wherein the positive electrode material consists essentially of an olivine phase and a dopant-rich secondary phase. The positive electrode material of claim 1, wherein the positive electrode material provides an energy density of at least 340 mWh/g and a specific capacitance of at least 110 mAh/g at a 20 C discharge rate during operation in the battery. The positive electrode material of claim 1, wherein the positive electrode material provides an energy density of at least 400 mWh/g and a specific capacitance of at least 125 mAh/g at a 20 C discharge rate during operation in the battery. The positive electrode material of claim 1, wherein D is one or more dopants selected from the group consisting of cobalt (Co), vanadium (V), and niobium (Nb). The positive electrode material of claim 1, wherein D is one or more dopants selected from the group consisting of cobalt (Co) and vanadium (V). A positive electrode comprising the positive electrode material as described in claim 1 of the patent application. The positive electrode of claim 20, which further comprises fluorine. The positive electrode of claim 20, wherein the positive electrode material provides at least a discharge rate of 20 C during operation in the battery. An energy density of 340 mWh/g and a specific capacitance of at least 110 mAh/g. The positive electrode of claim 20, wherein D is one or more dopants selected from the group consisting of cobalt (Co), vanadium (V), and niobium (Nb). The positive electrode of claim 20, wherein D is one or more dopants selected from the group consisting of cobalt (Co) and vanadium (V). A lithium secondary battery comprising: a positive electrode in electrical contact with a positive electrode current collector, the current collector being electrically coupled to an external circuit; a negative electrode in electrical contact with a negative electrode current collector, the current collection Electrically connected to the external circuit; a separator between the cathode and the anode and in ionic contact with the cathode and the anode; an electrolyte in ionic contact with the positive electrode and the negative electrode; The positive electrode includes the positive electrode material as described in claim 1; wherein the positive electrode further comprises fluorine as a dopant material; and wherein the positive electrode material is provided at a 20 C discharge rate during operation in the battery An energy density of at least 340 mWh/g and a specific capacitance of at least 110 mAh/g. A lithium secondary battery according to claim 25, wherein D is one or more dopants selected from the group consisting of: cobalt (Co), vanadium (V) and niobium (Nb). A lithium secondary battery according to claim 25, wherein D is one or more dopants selected from the group consisting of cobalt (Co) and vanadium (V).