JP7175284B2 - Alkaline metal batteries with deformable quasi-solid electrode materials - Google Patents

Description

CROSS-REFERENCES TO RELATED APPLICATIONS This application takes priority from U.S. Patent Application No. 15/604,606 filed May 24, 2017 and U.S. Patent Application No. 15/604,607 filed May 24, 2017 and the aforementioned patent application is incorporated herein by reference.

The present invention relates generally to the field of alkaline metal batteries, including rechargeable lithium metal batteries, sodium metal batteries, lithium ion batteries, sodium ion batteries, lithium ion capacitors and sodium ion capacitors.

Historically, today's most preferred rechargeable energy storage devices, namely lithium ion batteries, actually use lithium (Li) metal or Li alloys as anodes and Li intercalation compounds as cathodes. Evolved from the rechargeable "lithium metal battery" used. Li metal is an ideal anode material due to its light weight (lightest metal), high electronegativity (−3.04 V vs. standard hydrogen electrode), and high theoretical capacity (3,860 mAh/g). . Based on these outstanding properties, lithium metal batteries were proposed 40 years ago as an ideal system for high energy density applications. In the mid-1980s, several prototypes of rechargeable Li metal batteries were developed. One notable example is MOLI Energy, Inc. (Canada), which consisted of a Li metal anode and a molybdenum sulfide cathode. This cell, and several other cells from various manufacturers, suffer from a series of severely uneven Li growths (formation of Li dendrites) as the metal is replated during each subsequent recharge cycle. Abandoned due to safety issues. As the number of cycles increases, these dendrite or dendritic Li structures can eventually cross the separator to reach the cathode and cause an internal short circuit.

To overcome these safety issues, several alternative approaches have been proposed, modifying either the electrolyte or the anode. One approach involves replacing Li metal by graphite (another Li intercalating material) as the anode. The operation of such a battery involves shuttling Li-ions between two Li-insertion compounds, hence the name "Li-ion battery". Li-ion batteries are inherently safer than Li-metal batteries, presumably because the Li exists in an ionic state rather than a metallic state.

Lithium-ion batteries are the first choice energy storage devices for electric vehicle (EV), renewable energy storage, and smart grid applications. The last two decades have seen continuous improvements in energy density, rate performance, and safety in lithium-ion batteries, but somehow little attention has been paid to Li-metal batteries, which have significantly higher energy densities. it wasn't directed. However, the use of graphite-based anodes in Li-ion batteries has some major drawbacks, such as: Low specific capacity (372 mAh/g theoretical capacity as opposed to 3,860 mAh/g for Li metal); long Li intercalation requiring long recharge times (e.g. 7 hours for electric vehicle batteries) (e.g., low solid diffusion efficiency of Li into and out of graphite and inorganic oxide particles); inability to deliver high pulse power (power density <<1 kW/kg); 2. the need to use a high-quality cathode (eg, lithium cobaltate), which limits the choice of available cathode materials; Additionally, these commonly used cathodes have relatively low specific capacities (typically <200 mAh/g). These factors contribute to two major drawbacks of today's Li-ion batteries: low gravimetric and volumetric energy densities (typically 150-220 Wh/kg and 450-600 Wh/L), and low power densities (typically (all above values are based on total battery cell weight or volume).

Emerging EV and renewable energy industries require significantly higher gravimetric energy densities (e.g., >>250 Wh/kg, and preferably >>300 Wh/kg) than what current Li-ion battery technology can offer, and Availability of rechargeable batteries with high power density (shorter recharge time) is required. Furthermore, in the microelectronics industry, as consumers demand smaller volume, more compact portable devices (e.g., smartphones and tablets) that store more energy, significantly higher volumetric energy densities (>650 Wh/L, A battery with preferably >750 Wh/L) is needed. These requirements have led to a great deal of research effort towards developing electrode materials for lithium-ion batteries with higher specific capacity, excellent rate performance, and good cycling stability.

Several elements from groups III, IV, and V of the periodic table can form alloys with Li at certain desired voltages. Therefore, various anode materials and some metal oxides based on such elements have been proposed for lithium-ion batteries. Among them, silicon is recognized as one of the next generation anode materials for high energy lithium ion batteries. Because silicon has about ten times the theoretical gravimetric capacity (3,590 mAh/g based on Li _3.75 Si vs. 372 mAh/g for LiC ₆ ) compared to graphite, and a volumetric capacity of about This is because it is three times. However, the rapid volume change of Si (up to 380%) during lithium-ion alloying and dealloying (cell charge and discharge) often led to severe and rapid battery performance degradation. The performance degradation is mainly due to Si powdering due to volume change and the inability of the binder/conductive additive to maintain electrical contact between the powdered Si particles and the current collector. . Additionally, the inherently low electrical conductivity of silicon is another issue that needs to be addressed.

Although some high capacity anode active materials (eg Si) have been found, there is no corresponding high capacity cathode material available. Current cathode active materials commonly used in Li-ion batteries have significant drawbacks:
(1) practical capacities achievable with current cathode materials (e.g., lithium iron phosphate and lithium transition metal oxides) are limited to the range of 150-250 mAh/g, often less than 200 mAh/g; It is
(2) Lithium insertion into and removal from these commonly used cathodes is limited to solid state materials with very low diffusion coefficients (typically 10 ⁻⁸ to 10 ⁻¹⁴ cm ² /s) It relies on a very slow solid-state diffusion of Li in the particles, which leads to very low power densities, another long-standing problem of today's lithium-ion batteries.
(3) Current cathode materials are electrically and thermally insulating, unable to effectively and efficiently transport electrons and heat. Low conductivity means high internal resistance and the need to add large amounts of conductive additives, substantially reducing the proportion of electrochemically active material in the already low capacity cathode. Low thermal conductivity also means a higher tendency to undergo thermal runaway, which is a major safety issue in the lithium battery industry.

Low capacity anode or cathode active materials are not the only problem facing the lithium ion battery industry. There are significant design and manufacturing issues that the lithium-ion battery industry seems to be unaware of or largely ignores. For example, despite the high gravimetric capacity at the electrode level (based solely on the weight of the anode or cathode active material), as frequently claimed in the published and patent literature, these electrodes are disappointingly However, it cannot provide batteries with high capacity at the battery cell or pack level (based on total battery cell weight or pack weight). This is due to the observation that the actual active material mass loading of the electrodes is too low in these reports. In most cases, the active material mass loading (area density) of the anode is much lower than 15 mg/cm ² and is often <8 mg/cm ² (area density = per electrode cross-sectional area along the thickness of the electrode). amount of active material). The amount of cathode active material is typically 1.5 to 2.5 times the amount of anode active material. As a result, the weight ratio of anode active material (eg, graphite or carbon) in lithium ion batteries is typically 12% to 17%, and the weight ratio of cathode active material (eg, LiMn ₂ O ₄ ) is: 17% to 35% (mostly <30%). The combined weight fraction of cathode active material and anode active material is typically 30% to 45% of the cell weight.

As an entirely different class of energy storage device, sodium batteries are considered an attractive alternative to lithium batteries. Because sodium is plentiful, sodium production is much more environmentally friendly than lithium production. Furthermore, the high cost of lithium is a major problem.

Sodium-ion batteries using hard carbon-based anodes (Na-carbon intercalation compounds) and sodium transition metal phosphates as cathodes have been described by several research groups. However, these sodium-based devices exhibit much lower specific energy and rate capabilities than Li-ion batteries. These conventional sodium ion batteries require the diffusion of sodium ions into and out of the sodium intercalation compound at both the anode and cathode. The solid-state diffusion process required for sodium ions in sodium-ion batteries is much slower than the Li-diffusion process in Li-ion batteries, resulting in much lower power densities.

Instead of hard carbon or other carbonaceous intercalation compounds, sodium metal may be used as the anode active material in sodium metal cells. However, the use of metallic sodium as an anode active material is generally considered undesirable and dangerous due to problems with dendrite formation, interface aging, and electrolyte incompatibility. Most importantly, the same flammable solvents previously used in lithium secondary batteries are also used in most sodium metal or sodium ion batteries.

The low active material mass loading is primarily due to the inability to obtain relatively thick electrodes (greater than 100-200 μm) using conventional slurry coating procedures. This is not as easy a task as one might think, and in reality, electrode thickness is not a design parameter that can be arbitrarily and freely varied to optimize cell performance. Conversely, thicker samples tend to be very brittle or have poor structural integrity and require the use of large amounts of binder resin. Due to the low areal density and low volumetric density (related to thin electrodes and low packing density), the battery cell has a relatively low volumetric capacity and a low volumetric energy density.

With the increasing demand for more compact and portable energy storage systems, there is a strong interest in increasing battery volume utilization. To achieve improvements in cell volumetric capacity and energy density, new electrode materials and designs that allow high volumetric capacity and high mass loading are essential.

Thus, high active material mass loadings (high areal densities), high electrode thickness without significant reduction in electron and ion transport rates (e.g. with improved conductivity), high capacities, high power densities, and high The need for lithium and sodium batteries with energy densities is clear and urgent. These batteries must be produced in an environmentally friendly manner.

The present invention provides lithium and sodium batteries with high active material mass loading, very low overhead weight and volume (relative to active material mass and volume), high capacity, and unprecedented high energy and power densities. A method for manufacturing is provided. The lithium and sodium batteries can be primary (non-rechargeable) or secondary (rechargeable), rechargeable lithium and sodium metal batteries (with lithium or sodium metal anodes) and lithium ion or sodium ion batteries (e.g. , having a first lithium intercalation compound as an anode active material and a second lithium intercalation or absorption compound having a much higher electrochemical potential than the first lithium intercalation compound as a cathode active material. have). The alkaline batteries also include lithium ion capacitors and sodium ion capacitors, where the anode is a lithium ion or sodium ion cell type anode and the cathode is a supercapacitor cathode (e.g. electric double layer capacitor or redox pseudocapacitor activated carbon or graphene sheets as active materials for use in

In certain embodiments, the present invention provides (a) from about 30% to about 95% by volume of a cathode active material and from about 5% to about 40% by volume of a first cathode active material and from about 5% to about 40% by volume of an alkali salt dissolved in a solvent. and from about 0.01% to about 30% by volume of a conductive additive, the conductive additive containing conductive filaments forming a 3D network of electronic conduction paths. (b) the anode; and (c) disposed between the anode and the quasi-solid cathode, wherein the quasi-solid cathode has a conductivity of from about 10 ⁻⁶ S/cm to about 300 S/cm. A quasi-solid cathode provides an alkali metal cell with a thickness of 200 μm or more in an alkali metal cell with a coated ion-conducting membrane or porous separator. Preferably, the semi-solid cathode has a weight of 10 mg/cm ² or more, preferably 15 mg/cm ² or more, more preferably 25 mg/cm ² or more, more preferably 35 mg/cm ² or more, even more preferably 45 mg/cm ² or more, Most preferably it contains a cathode active material mass loading greater than 65 mg/cm ² .

In this cell, the anode comprises from about 30% to about 95% by volume of anode active material, from about 5% to about 40% by volume of a second electrolyte containing an alkali salt dissolved in a solvent, and from about 0 .01% to about 30% by volume of a conductive additive, said conductive additive containing conductive filaments forming a 3D network of electronic conducting pathways; A quasi-solid electrode has a conductivity of about 10 ⁻⁶ S/cm to about 300 S/cm, and a quasi-solid anode has a thickness of 200 μm or more. Preferably, the semi-solid anode has a concentration of 10 mg/cm ² or more, preferably 15 mg/cm ² or more, more preferably 25 mg/cm ² or more, more preferably 35 mg/cm ² or more, even more preferably 45 mg/cm ² or more, Most preferably it contains an anode active material mass loading greater than 65 mg/cm ² .

In certain embodiments, the present invention provides (A) from about 30% to about 95% by volume of an anode active material and from about 5% to about 40% by volume of an electrolyte containing an alkali salt dissolved in a solvent. and from about 0.01% to about 30% by volume of a conductive additive, wherein the conductive additive containing conductive filaments forms a 3D network of electronic conduction paths, A quasi-solid electrode having a conductivity of about 10 ⁻⁶ S/cm to about 300 S/cm was disposed between the quasi-solid anode, (B) the cathode, and (C) the anode and the quasi-solid cathode. In alkali metal cells with ion-conducting membranes or porous separators, the quasi-solid cathode provides alkali metal cells with a thickness of 200 μm or more.

The present invention also provides a method of preparing an alkali metal cell having a quasi-solid electrode comprising: (a) an amount of active material (anode active material or cathode active material); an amount of electrolyte; to form a deformable conductive electrode material, wherein a conductive additive containing conductive filaments forms a 3D network of electron-conducting pathways; The step of forming as a solid electrode, wherein the electrode has 10 ⁻⁶ S/cm or more (preferably 10 ⁻⁵ S/cm or more, more preferably 10 ⁻³ S/cm or more, further preferably 10 ⁻² S/cm or more). above, still more preferably and typically 10 ⁻¹ S/cm or more, still more typically and preferably 1 S/cm or more, still more typically and preferably 10 S/cm or more, and at most (c) forming a second electrode, including transforming the electrode material into an electrode shape without disturbing the 3D network of electronic conduction paths so as to maintain a conductivity of 300 S/cm; and (the second electrode may be a quasi-solid electrode); and (d) combining the quasi-solid electrode and the second electrode with an ion-conducting separator disposed between the two electrodes, and forming an alkali metal cell.

The electrolyte is dissolved in the liquid solvent at a salt concentration of 2.5M to 14M, preferably greater than 3M, more preferably greater than 3.5M, even more preferably greater than 5M, even more preferably greater than 7M, even more preferably greater than 10M. It may be a semi-solid electrolyte containing a lithium salt or a sodium salt. At salt concentrations of 2.5 M and above, the electrolyte is no longer a liquid electrolyte, but a quasi-solid electrolyte. In certain embodiments, the electrolyte is a semi-solid electrolyte containing a lithium or sodium salt dissolved in a liquid solvent at a salt concentration of 3.0M to 11M.

In certain embodiments, the conductive filaments are carbon fibers, graphite fibers, carbon nanofibers, graphite nanofibers, carbon nanotubes, needle coke, carbon whiskers, conductive polymer fibers, conductive material-coated fibers, metal nanowires, metal fibers. , metal wires, graphene sheets, expanded graphite platelets, combinations thereof, or combinations thereof with non-filamentary conductive particles.

In certain embodiments, the electrode maintains an electrical conductivity of 10 ⁻⁵ S/cm to about 1 S/cm.

In certain embodiments, the deformable electrode material has an apparent viscosity greater than or equal to about 10000 Pa·s measured at an apparent shear rate of 1000 s ⁻¹ . In certain embodiments, the deformable electrode material has an apparent viscosity of about 100,000 Pa·s or greater at an apparent shear rate of 1000 s ⁻¹ .

In this method, the amount of active material is typically about 20% to about 95% by volume of the electrode material, more typically about 35% to about 85% by volume of the electrode material, most typically is about 50% to about 75% by volume of the electrode material.

Preferably, the step of combining the active material, conductive additive and electrolyte (including dissolving the lithium or sodium salt in the liquid solvent) follows a specific order. This step involves first dispersing the conductive filaments in a liquid solvent to form a homogeneous suspension, then adding the active material to the suspension and adding the lithium salt or sodium salt to the liquid solvent of the suspension. including dissolving in In other words, the conductive filaments should be uniformly dispersed in the liquid solvent before adding other ingredients such as active materials and before dissolving the lithium salt or sodium salt in the liquid solvent. This order is essential to achieve percolation of the conducting filaments to form a 3D network of electronic conduction pathways. If such an order is not followed, percolation of the conductive filaments will not occur, or will occur only when a very large proportion of the conductive filaments (eg, greater than 10% by volume) is added. Such a very large fraction of conductive filaments reduces the fraction of active material and thus the energy density of the cell.

In certain embodiments, combining the electrode materials to form a quasi-solid electrode comprises dissolving a lithium or sodium salt in a liquid solvent to form an electrolyte having a first salt concentration, followed by removing a portion to increase the salt concentration to obtain a semi-solid electrolyte having a second salt concentration, the second salt concentration being higher than the first concentration, preferably greater than 2.5M. is also high (more preferably 3.0M to 14M).

The step of removing a portion of the solvent is done so that the electrolyte is supersaturated without causing salt precipitation or crystallization. In certain preferred embodiments, the liquid solvent comprises a mixture of at least a first liquid solvent and a second liquid solvent, the first liquid solvent being more volatile than the second liquid solvent, and the liquid Removing a portion of the solvent includes partially or completely removing the first liquid solvent.

There is no limit to the type of anode active material or cathode active material that can be used in practicing the present invention. Preferably, however, the anode active material is less than 1.0 ^{volts (} preferably ⁰ .7 volts) above the electrochemical potential.

In certain preferred embodiments, the alkali metal cell is a lithium metal battery, lithium ion battery, or lithium ion capacitor, and the anode active material comprises (a) particles of lithium metal or a lithium metal alloy; (b) natural graphite. (c) silicon (Si ), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), nickel (Ni), cobalt (Co), manganese (Mn ), titanium (Ti), iron (Fe), and cadmium (Cd); and (d) alloys or intermetallics of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, or Cd with other elements (e) Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ni, Co, Ti, which are compounds, stoichiometric or non-stoichiometric; , Mn, or Cd oxides, carbides, nitrides, sulfides, phosphides, selenides, and tellurides, and mixtures or composites thereof; (f) prelithiated versions thereof; g) prelithiated graphene sheets; and combinations thereof.

In certain embodiments, the alkali metal cell is a sodium metal cell or a sodium ion cell and the active material is petroleum coke, carbon black, amorphous carbon, activated carbon, hard carbon (difficult to graphitize carbon), soft carbon ( readily graphitizable carbon), template carbon, hollow carbon nanowires, hollow carbon _spheres , _titanates , _{NaTi2 ( PO4} ) ₃ , _{Na2Ti3O7 , Na2C8H4O4 , Na2TP} , Na _x TiO ₂ (x=0.2-1.0), Na ₂ C ₈ H ₄ O ₄ , carboxylic acid-based materials, C ₈ H ₄ Na ₂ O ₄ , C ₈ H ₆ O ₄ , C _{8 sodium intercalate selected from H5NaO4 , C8Na2F4O4 , C10H2Na4O8 , C14H4O6 , C14H4Na4O8 , or combinations thereof} It is an anode active material containing an ion compound.

In certain embodiments, the alkali metal cell is a sodium metal cell or a sodium ion cell and the active material is an anode active material selected from the group consisting of: (a) particles of sodium metal or sodium metal alloy; (b) natural graphite particles, synthetic graphite particles, mesocarbon microbeads (MCMB), carbon particles, needle coke, carbon nanotubes, carbon nanofibers, carbon fibers, and graphite fibers; (c) sodium-doped silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al); , titanium (Ti), cobalt (Co), nickel (Ni), manganese (Mn), cadmium (Cd), and mixtures thereof; and (d) Si, Ge, Sn, Pb, Sb, Bi, Zn, Al (e) Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ti, Co, sodium-containing oxides, carbides, nitrides, sulfides, phosphides, selenides, tellurides, or antimonides of Ni, Mn, Cd, and mixtures or composites thereof; ) graphene sheets preloaded with sodium ions; and combinations thereof.

In certain embodiments, the alkali metal cell is a sodium metal cell or a sodium ion cell, and the active materials are inorganic materials, organic or polymeric materials, metal oxides/phosphates/sulfides, or combinations thereof. A cathode active material containing a selected sodium intercalation compound or sodium absorption compound. Metal oxides/phosphates/sulfides are sodium cobaltate, sodium nickelate, sodium manganate, sodium vanadate, sodium mixed metal oxide, sodium/potassium transition metal oxide, sodium iron phosphate, iron phosphate It may be selected from sodium/potassium, sodium manganese phosphate, sodium/potassium manganese phosphate, sodium vanadium phosphate, sodium/potassium vanadium phosphate, sodium mixed metal phosphate, transition metal sulfide, or combinations thereof.

The inorganic material may be selected from sulfur, sulfur compounds, lithium polysulfides, transition metal dichalcogenides, transition metal trichalcogenides, or combinations thereof. In certain embodiments, the inorganic material is selected from _TiS2 , _TaS2 , MoS2, _NbSe3 , _{MnO2 , CoO2} , iron oxide, vanadium oxide, or combinations thereof.

In some embodiments, the alkali metal cell is a sodium metal cell or a sodium ion cell and the active materials are _NaFePO4 , Na _{(1-x) KxPO4 , Na0.7FePO4 ,} Na1 _{. 5 VOPO4F0.5} , _{Na3V2 ( PO4} ) _{3 , Na3V2 ( PO4} ) _2F3 , _{Na2FePO4F , NaFeF3} , _{NaVPO4F , Na3V2 ( PO4} ) _{2F3 , Na1.5VOPO4F0.5 , Na3V2 ( PO4 ) 3 , NaV6O15 , NaxVO2 , Na0.33V2O5 , NaxCoO2 ,} Na _2/3 [Ni _1/3 Mn _2/3 ]O ₂ , Na _x (Fe _1/2 Mn _1/2 )O ₂ , Na _x MnO ₂ , λ-MnO ₂ , Na _x K _{(1−x) MnO2} , _Na0.44MnO2 , _Na0.44MnO2 /C, _Na4Mn9O18 , _{NaFe2Mn ( PO4} ) _{3 , Na2Ti3O7 , Ni1 / 3Mn1 / 3 Co1} / _3O2 , _{Cu0.56Ni0.44HCF} , _NiHCF , _NaxMnO2 , _{NaCrO2 , Na3Ti2 ( PO4} ) _{3 , NiCo2O4 , Ni3S2} / _FeS2 , Sb ₂ O ₄ , Na ₄ Fe(CN) ₆ /C, NaV _1-x Cr _x PO ₄ F, Se _z Sy ( _y /z=0.01-100), Se, aluordite, or combinations thereof A cathode active material containing a sodium intercalation compound selected from wherein x is 0.1 to 1.0.

In some preferred embodiments, the cathode active material is lithium cobaltate, doped lithium cobaltate, lithium nickelate, doped lithium nickelate, lithium manganate, doped lithium manganate, lithium vanadate, Lithium selected from the group consisting of doped lithium vanadates, lithium mixed metal oxides, lithium iron phosphates, lithium vanadium phosphates, lithium manganese phosphates, lithium mixed metal phosphates, metal sulfides, and combinations thereof. Contains intercalation compounds.

The electrolyte is an aqueous liquid, an organic liquid, an ionic liquid (ionic salts with a melting temperature below 100° C., preferably below 25° C. at room temperature), or an ionic liquid in a ratio of 1/100 to 100/1. It can be a mixture with an organic liquid. Organic liquids are preferred, but ionic liquids are preferred.

In preferred embodiments, the quasi-solid electrode has a thickness of 200 μm to 1 cm, preferably 300 μm to 0.5 cm (5 mm), more preferably 400 μm to 3 mm, most preferably 500 μm to 2.5 mm (2500 μm). When the active material is an anode active material, the anode active material has a mass loading of 25 mg/cm ² or more (preferably 30 mg/cm ² or more, more preferably 35 mg/cm ² or more); and/or At least 25% (preferably at least 30%, more preferably at least 35%) of the weight or volume of the entire battery cell. When the active material is a cathode active material, the cathode active material is preferably 20 mg/cm ² or more (preferably 25 mg/cm ² or more, more preferably 30 mg/cm ² or more) within the cathode for organic or polymeric materials. ) and, for inorganic and non-polymeric materials, a mass loading of 45 mg/cm ² or more (preferably 50 mg/cm ² or more, more preferably 55 mg/cm ² or more) in the cathode. and/or comprise at least 45% (preferably at least 50%, more preferably at least 55%) by weight or volume of the entire battery cell.

The foregoing requirements for electrode thickness, area mass loading of anode active material or mass fraction relative to the entire battery cell, or area mass loading or mass fraction relative to the entire battery cell of cathode active material, overcome conventional slurry coating and drying methods. This was not possible with conventional lithium or sodium batteries using .

In some embodiments, the anode active material is pure graphene, graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide, graphene hydride, graphene nitride, boron-doped A prelithiated version of graphene sheet selected from graphene, nitrogen-doped graphene, chemically functionalized graphene, physically or chemically activated or etched versions thereof, or combinations thereof. Surprisingly, without prelithiation, the resulting lithium battery cells do not exhibit adequate cycle life (ie, capacity fades rapidly).

In some embodiments of the method according to the invention, the cell comprises a lithium intercalation compound or lithium intercalation compound selected from inorganic materials, organic or polymeric materials, metal oxides/phosphates/sulfides, or combinations thereof. A lithium metal or lithium ion cell containing a cathode active material selected from absorption compounds. For example, metal oxides/phosphates/sulfides include lithium cobaltate, lithium nickelate, lithium manganate, lithium vanadate, lithium mixed metal oxide, lithium iron phosphate, lithium manganese phosphate, lithium vanadium phosphate. , lithium mixed metal phosphates, transition metal sulfides, and combinations thereof. The inorganic material is selected from sulfur, sulfur compounds, lithium polysulfide, transition metal dichalcogenides, transition metal trichalcogenides, or combinations thereof. In particular, the inorganic material is selected from _TiS2 , _TaS2 , MoS2, _NbSe3 , _{MnO2 , CoO2} , iron oxide, vanadium oxide, or combinations thereof. These are discussed further below.

In this lithium metal battery, the cathode active material comprises a lithium intercalation compound selected from metal carbides, metal nitrides, metal borides, metal dichalcogenides, or combinations thereof. In some embodiments, the cathode active material is niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, vanadium, chromium, cobalt, manganese, in the form of nanowires, nanodiscs, nanoribbons, or nanoplatelets. A lithium intercalation compound selected from iron or nickel oxides, dichalcogenides, trichalcogenides, sulfides, selenides or tellurides. Preferably, the cathode active material is (a) bismuth selenide or bismuth telluride, (b) a transition metal dichalcogenide or trichalcogenide, (c) niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, cobalt, manganese. sulfides, selenides, or tellurides of iron, nickel, or transition metals; (d) boron nitride; or (e) combinations thereof. or a lithium intercalation compound selected from nanosheets, wherein the discs, platelets, or sheets have a thickness of less than 100 nm.

In some embodiments, the lithium metal battery wherein the cathode active material is poly(anthraquinonyl sulfide) (PAQS), lithium oxocarbon, 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA ), poly(anthraquinonyl sulfide), pyrene-4,5,9,10-tetraone (PYT), polymer-bound PYT, quino (triazene), redox-active organic material, tetracyanoquinodimethane (TCNQ), tetra Cyanoethylene (TCNE), 2,3,6,7,10,11-hexamethoxytriphenylene (HMTP), poly(5-amino-1,4-dihydroxyanthraquinone) (PDAQ), phosphazene disulfide polymer ([(NPS ₂ ) ₃ ]n), lithiated 1,4,5,8-naphthalenetetraol formaldehyde polymer, hexaazatrinaphthylene (HATN), hexaazatriphenylene hexacarbonitrile (HAT(CN) ₆ ), 5-benzylidene hydantoin, isatin lithium salt, pyromellitic diimide lithium salt, tetrahydroxy-p-benzoquinone derivative (THQLi ₄ ), N,N'-diphenyl-2,3,5,6-tetraketopiperazine (PHP), N,N '-diallyl-2,3,5,6-tetraketopiperazine (AP), N,N'-dipropyl-2,3,5,6-tetraketopiperazine (PRP), thioether polymer, quinone compound, 1,4 -benzoquinone, 5,7,12,14-pentacentetrone (PT), 5-amino-2,3-dihydro-1,4-dihydroxyanthraquinone (ADDAQ), 5-amino-1,4-dihydroxyanthraquinone (ADAQ) , calixquinone, Li ₄ C ₆ O ₆ , Li ₂ C ₆ O ₆ , Li ₆ C ₆ O ₆ , or combinations thereof.

Thioether polymers include poly[methantetriyl-tetra(thiomethylene)] (PMTTM), poly(2,4-dithiopentanylene) (PDTP), poly(ethene-1,1,2,2-tetrathiol as backbone thioether polymer ) (PETT), a side-chain thioether polymer with a backbone composed of conjugated aromatic moieties and pendant thioether side chains, poly(2-phenyl-1,3-dithiolane) (PPDT), poly( 1,4-di(1,3-dithiolan-2-yl)benzene) (PDDTB), poly(tetrahydrobenzodithiophene) (PTHBDT), poly[1,2,4,5-tetrakis(propylthio)benzene] ( PTKPTB, or poly[3,4(ethylenedithio)thiophene] (PEDTT).

In preferred embodiments, the cathode active material is copper phthalocyanine, zinc phthalocyanine, tin phthalocyanine, iron phthalocyanine, lead phthalocyanine, nickel phthalocyanine, vanadyl phthalocyanine, fluorochrome phthalocyanine, magnesium phthalocyanine, manganese phthalocyanine, dilithium phthalocyanine, phthalocyanine chloroaluminum, cadmium. An organic material comprising a phthalocyanine compound selected from phthalocyanines, chlorogallium phthalocyanines, cobalt phthalocyanines, silver phthalocyanines, metal-free phthalocyanines, chemical derivatives thereof, or combinations thereof.

In this lithium metal battery, the cathode active material has an electrode active material loading of greater than 30 mg/ ^cm2 (preferably greater than 40 mg/ ^cm2 , more preferably greater than 45 mg/ ^cm2 , and most preferably greater than 50 mg/ ^cm2 ). and/or the first electrically conductive foam structure has a thickness of 300 μm or greater (preferably 400 μm or greater, more preferably 500 μm or greater, and may even be greater than 600 μm).

FIG. 1(A) shows an anode current collector, one or two anode active material layers (e.g., thin Si coating layers) coated on two major surfaces of the anode current collector, a porous separator and an electrolyte. 1 is a schematic diagram of a prior art lithium-ion battery cell composed of , one or two cathode electrode layers (eg, sulfur layers), and a cathode current collector; FIG. FIG. 1B shows that the electrode layer comprises discrete particles of active material (eg, graphite or tin oxide particles in the anode layer or LiCoO ₂ in the cathode layer), a conductive additive (not shown), and a resin. 1 is a schematic diagram of a prior art lithium-ion battery constructed from a binder (not shown); FIG. FIG. 1(C) shows a quasi-solid anode (consisting of anode active material particles and conductive filaments directly mixed or dispersed in the electrolyte), a porous separator, and a quasi-solid cathode (mixed or dispersed directly in the electrolyte). 1 is a schematic diagram of a lithium-ion battery cell according to the present invention, comprising a cathode active material particle and a conductive filament; In this embodiment, no resin binder is required. FIG. 1(D) shows an anode (containing a lithium metal layer deposited on a Cu foil surface), a porous separator, and a quasi-solid cathode (cathode active material particles mixed or dispersed directly in the electrolyte and conductive 1 is a schematic diagram of a lithium metal battery cell according to the present invention, comprising a filament; In this embodiment, no resin binder is required. Figure 2(A) plots the vapor pressure ratio data (ps/p = solution vapor pressure/solvent-only vapor pressure) as a function of the sodium salt molar ratio x ( _NaTFSI /DOL) using the classical Raoult law FIG. 10 is a diagram with theoretical predictions based on; FIG. 2(B) plots the vapor pressure ratio data (ps/p=solution vapor pressure/solvent-only vapor pressure) as a function of the sodium salt molar ratio x ( _NaTFSI /DME) according to classical Raoult's law. FIG. 10 is a diagram with theoretical predictions based on; FIG. 2(C) plots the vapor pressure ratio data ( _ps /p=solution vapor pressure/solvent-only vapor pressure) as a function of sodium salt molar ratio x( _NaPF6 /DOL) using the classical Raoult law FIG. 3 is a diagram with theoretical predictions based on . FIG. 2(D) shows vapor pressure ratio data (ps/p=vapor pressure of solution/vapor pressure of solvent alone) as a function of sodium salt molecular ratio x ( _NaTFSI /DOL, NaTFSI/DME, _NaPF6 /DOL). , along with theoretical predictions based on classical Raoult's law. FIG. 3(A) is a schematic diagram of a dense and highly ordered structure of a solid electrolyte. FIG. 3(B) is a schematic diagram of a completely amorphous liquid electrolyte with a large fraction of free volume in which cations (eg, Na ⁺ ) can easily move. FIG. 3(C) Disordered or amorphous quasi-solid electrolyte with solvent molecules segregating salt species to produce amorphous regions where free (non-clustered) cations can readily migrate. 1 is a schematic diagram of a structure; FIG. FIG. 4(A) is a diagram showing Na ⁺ ion transference numbers in electrolytes (eg, NaTFSI salt/(DOL+DME) solvent) in relation to sodium salt molecular ratio x. FIG. 4(B) is a diagram showing Na ⁺ ion transference numbers in electrolytes (eg, NaTFSI salt/(EMImTFSI+DOL) solvent) in relation to sodium salt molecular ratio x. FIG. 4(C) is a diagram showing Na ⁺ ion transference numbers in electrolytes (eg, NaTFSI salt/(EMImTFSI+DME) solvent) in relation to sodium salt molecular ratio x. FIG. 4(D) shows the Na ⁺ ion transference numbers in various electrolytes (such as those in FIGS. 6-8) in relation to the sodium salt molecular ratio x. FIG. 5 shows the results for producing exfoliated graphite, expanded graphite flakes (>100 nm thick), and graphene sheets (thickness <100 nm, more typically <10 nm, and can be as thin as 0.34 nm). 1 is a schematic diagram of a commonly used method; FIG. FIG. 6(A) shows the conductivity (percolation behavior) of the conducting filaments in the quasi-solid electrode plotted as a function of the volume fraction of the conducting filaments (carbon nanofibers). FIG. 6(B) shows the conductivity (percolation behavior) of the conducting filaments in the quasi-solid electrode plotted as a function of the volume fraction of the conducting filaments (reduced graphene oxide sheets). FIG. 7 is a Ragone plot (weight power density versus energy density) of a lithium-ion battery cell containing graphite particles as the anode active material and carbon-coated LFP particles as the cathode active material. Three of the four data curves are for cells prepared according to embodiments of the present invention and the remaining one is for conventional slurry coating (roll coating) of electrodes. FIG. 8 shows a Ragone plot (gravimetric power density versus gravimetric energy density) of the three cells. Each cell contains graphene _- encapsulated Si nanoparticles as anode active material and LiCoO2 nanoparticles as cathode active material. Experimental data were obtained from Li-ion battery cells prepared by the method according to the invention (following sequences S1 and S3) and conventional slurry coating of electrodes. FIG. 9 contains lithium foil as anode active material, dilithium rhodizonate (Li ₂ C ₆ O ₆ ) as cathode active material, and lithium salt (LiPF ₆ )-PC/DEC as organic electrolyte. Ragone plot of a lithium metal battery. The data are lithium metal cells prepared by the method according to the invention (sequence S2 and S3 using two different salt concentrations) and conventional slurry coating of electrodes. FIG. 10 is a Ragone plot of two sodium ion capacitors each containing pre-sodiumized hard carbon particles as anode active material and graphene sheets as cathode active material. One cell has an anode prepared by a conventional slurry coating process and the other cell has a semi-solid anode prepared according to the method according to the invention.

The present invention is directed to methods of manufacturing lithium or sodium batteries that exhibit very high volumetric energy densities heretofore unrealized. The battery, which may be a primary battery, is selected from a lithium ion battery, a lithium metal secondary battery (e.g. using lithium metal as the anode active material), a sodium ion battery, a sodium metal battery, a lithium ion capacitor, or a sodium ion capacitor. It is preferably a secondary battery that Batteries are based on aqueous electrolytes, non-aqueous or organic electrolytes, ionic liquid electrolytes, or mixtures of organic and ionic liquids. Preferably, the electrolyte is a "semi-solid electrolyte" containing a high concentration of lithium or sodium salt in a liquid solvent and behaves like a solid, but with the desired amount of conductive filaments and active material in the electrolyte. (hence the term “deformable quasi-solid electrode material”). The shape of the lithium battery may be cylindrical, square, button-like, and the like. The invention is not limited to any battery shape or configuration.

For convenience, illustrative examples of cathode active materials include lithium iron phosphate (LFP), vanadium oxide ( _VxOy ), _{dilithium rhodizonate ( Li2C6O6} ), and copper phthalocyanine (CuPc); Examples of anode active materials include selected materials such as graphite, hard carbon, SnO, _{Co3O4 ,} and Si particles. They should not be construed as limiting the scope of the invention.

As shown in FIG. 1A, prior art lithium battery cells typically include an anode current collector (e.g., Cu foil) and an anode electrode or anode active material layer (e.g., Cu foil) on one side. or a Li metal foil or prelithiated Si coating deposited on two sides), a porous separator and/or electrolyte component, and a cathode electrode or cathode active material layer (or two cathodes coated on two sides of an Al foil). active material layer) and a cathode current collector (eg, Al foil).

In the more commonly used prior art cell construction (FIG. 1(B)), the anode layer consists of anode active material (e.g. graphite, hard carbon, or Si), conductive additive (e.g. carbon black particles), ), and particles of a resin binder (eg SBR or PVDF). The cathode layer is composed of particles of cathode active material (eg, LFP particles), conductive additive (eg, carbon black particles), and resin binder (eg, PVDF). Both the anode and cathode layers are typically up to 100-200 μm thick, and are likely to produce a sufficient amount of current per unit electrode area. This thickness range is considered an industry accepted constraint with which battery designers routinely work. This thickness limitation is due to several reasons: (a) existing battery electrode coating machines are not equipped to coat very thin or very thick electrode layers; (b) thinner layers are preferred given the reduced lithium-ion diffusion path length; (c) thicker electrodes are prone to delamination or cracking during drying or handling after roll coating; and (d) minimum overhead weight and maximum lithium storage capacity, and therefore maximum energy density ( In order to obtain the Wk/kg or Wh/L of the cell, all non-active material layers (eg, current collectors and separators) within the battery cell must be kept to a minimum.

In less commonly used cell configurations, the anode active material (e.g., Si coating) or cathode active material (e.g., lithium transition metal oxide) is coated with copper foil or It is deposited in the form of a thin film directly on a current collector such as Al foil. However, such thin film structures with very small dimensions in the thickness direction (typically much less than 500 nm, and often less than 100 nm if desired) do not provide the same (assuming ) that only a small amount of active material can be incorporated into the electrode, reducing the total lithium storage capacity and reducing the lithium storage capacity per unit electrode surface area. Such thin films should be less than 100 nm thick in order to be more resistant to cycling-induced cracking (for the anode) or to facilitate full utilization of the cathode active material. Such constraints further reduce the total lithium storage capacity and the lithium storage capacity per unit electrode surface area. Such thin film batteries have a very limited range of applications.

On the anode side, Si layers thicker than 100 nm have been found to be less crack resistant during charge-discharge cycling of the battery. The Si layer is fractured in just a few cycles. On the cathode side, a sputtered layer of lithium metal oxide thicker than 100 nm does not allow the lithium ions to fully penetrate and reach the entire cathode layer, resulting in low cathode active material utilization. Desirable electrode thickness is at least 100 μm and individual active material coatings or particles desirably have dimensions less than 100 nm. Therefore, these thin film electrodes (with thickness <100 nm) deposited directly on the current collector are three orders of magnitude short of the required thickness. As a further problem, not all cathode active materials are conductive to both electrons and lithium ions. A large layer thickness implies a very high internal resistance and a low active material utilization. Sodium batteries have similar problems.

That is, there are several conflicting factors that must be considered simultaneously in the design and selection of cathode or anode active materials in terms of material type, size, electrode layer thickness, and active material mass loading. So far, there have been no effective solutions provided by any prior art teachings to these often-conflicting problems. As disclosed herein, the inventors have puzzled battery designers and also electrochemists for over 30 years by developing novel methods of manufacturing lithium and sodium batteries. solved these problems.

Prior art lithium battery cells are typically manufactured by a method comprising the following steps: (a) the first step is to prepare an anode active material (e.g. Si nanoparticles or mesocarbon microbeads, MCMB); , conductive filler (eg graphite flakes), and resin binder (eg PVDF) particles in a solvent (eg NMP) to form an anode slurry. Separately, particles of cathode active material (e.g., LFP particles), conductive filler (e.g., acetylene black), and resin binder (e.g., PVDF) are mixed and dispersed in a solvent (e.g., NMP). to form a cathode slurry. (b) the second step is to coat one or both major surfaces of the anode current collector (e.g. Cu foil) with the anode slurry and dry the coated layer by evaporating the solvent (e.g. NMP); to form a dry anode electrode coated on Cu foil. Similarly, the cathode slurry is coated and dried to form a dry cathode electrode coated on Al foil. In practical manufacturing situations, slurry coating is usually done in a roll-to-roll manner; (c) the third step is to laminate the anode/Cu foil sheet, porous separator layer and cathode/Al foil sheet together , to form a 3- or 5-layer assembly, which is cut or slit to the desired size and laminated to form a rectangular structure (as an example shape) or rolled into a cylindrical cellular structure. including doing (d) The rectangular or cylindrical laminated structure is then encased in an aluminum plastic laminated envelope or steel casing. (e) then injecting a liquid electrolyte into the laminate structure to fabricate a lithium battery cell;

There are several significant problems associated with this method and the resulting lithium battery cells.
1) It is very difficult to manufacture electrode layers (anode or cathode layers) thicker than 200 μm. There are several reasons. A 100-200 μm thick electrode typically requires a heating zone of 30-50 meters in length in a slurry coating facility, which is too time consuming, too energy consuming and cost effective. do not have. For some electrode active materials, such as metal oxide particles, it has not been possible to continuously produce electrodes with good structural integrity thicker than 100 μm in a practical manufacturing environment. The resulting electrodes are very fragile and brittle. Thicker electrodes are more prone to delamination and cracking.
2) In the conventional method as shown in FIG. 1(A), the actual mass loading of the electrodes and the apparent density for the active material are too low to achieve gravimetric energy densities above 200 Wh/kg. Mostly, even for relatively large graphite particles, the anode active material mass loading (area density) of the electrode is well below 25 mg/cm ² and the apparent volume or tap density of the active material is typically 1.2 g. / ^cm3 . The cathode active material mass loading (area density) of the electrode is substantially lower than 45 mg/cm ² for inorganic materials based on lithium metal oxides and substantially lower than 15 mg/cm ² for organic or polymeric materials. . In addition, there are numerous other non-active materials (eg, conductive additives and resin binders) that add additional weight and volume to the electrodes without contributing to battery capacity. These low areal densities and low volume densities result in relatively low gravimetric and low volumetric energy densities.
3) The conventional method requires the electrode active materials (anode active material and cathode active material) to be dispersed and slurried in a liquid solvent (e.g., NMP), and the liquid solvent is applied after coating the current collector surface. After removal, the electrode layer must be dried. After the anode and cathode layers are laminated together with a separator layer and packaged in a housing to form a supercapacitor cell, a liquid electrolyte is injected into the cell. In practice, the two electrodes are wetted, then the electrodes are dried and finally wetted again. Such a wet-dry-wet process does not appear to be a good process.
4) Current lithium-ion batteries still suffer from relatively low gravimetric energy densities and low volumetric energy densities. Commercially available lithium-ion batteries exhibit gravimetric energy densities of about 150-220 Wh/kg and volumetric energy densities of 450-600 Wh/L.

In the literature, energy densities for practical battery cells or devices cannot be directly derived from energy density data reported based on active material weight alone or electrode weight. "Overhead weight", ie the weight of other device components (binders, conductive additives, current collectors, separators, electrolytes, and packaging) must also be taken into account. In conventional manufacturing methods, the weight ratio of anode active material (eg, graphite or carbon) in lithium-ion batteries is typically 12%-17%, and the weight ratio of cathode active material (eg, LiMn ₂ O ₄ ) is typically 12%-17%. The ratio is between 20% and 35%.

The present invention provides a method of manufacturing lithium or sodium battery cells with high electrode thickness, high active material mass loading, low overhead weight and volume, high capacity, and high energy density.

In certain embodiments, the method includes the following steps.
(a) combining an amount of active material (either anode active material or cathode active material), an amount of electrolyte, and a conductive additive to form a deformable conductive electrode material; Here, a conductive additive containing conductive filaments forms a 3D network of electronic conduction pathways (these conductive filaments, such as carbon nanotubes and graphene sheets, before being mixed with the particles of active material and the electrolyte). are a mass of irregularly agglomerated filaments.The mixing procedure involves dispersing these conductive filaments in a high viscosity electrolyte containing particles of active material.This is described in a later section. discussed further in);
(b) forming the electrode material as a quasi-solid electrode; Here, in this forming step, the electrode is 10 ⁻⁶ S/cm or more (preferably 10 ⁻⁵ S/cm or more, more preferably 10 ⁻⁴ S/cm or more, further preferably 10 ⁻³ S/cm or more, even more preferably and typically 10 ⁻² S/cm, even more typically and preferably 10 ⁻¹ S/cm, even more typically and preferably 1 S/cm or more; up to 300 S/cm was observed), deforming the electrode material into the electrode shape without disturbing the 3D network of electronic conduction pathways;
(c) forming a second electrode (the second electrode may be a quasi-solid electrode or a conventional electrode); and (d) placing the quasi-solid electrode and the second electrode between the two electrodes. Forming an alkali metal cell by combining with an ion-conducting separator disposed thereon.

As shown in FIG. 1C, one preferred embodiment of the present invention comprises a conductive semi-solid anode 236, a conductive semi-solid cathode 238, and a porous separator 240 ( or ion permeable membrane). These three components are typically housed in a protective housing (not shown), which typically has an anode tab (terminal) connected to the anode and a terminal connected to the cathode. and a cathode tab (terminal). These tabs are for connecting an external load (eg an electronic device that should be powered by the battery). In this particular embodiment, the semi-solid anode 236 comprises an anode active material (eg, Si particles, not shown in FIG. 1(C)) and an electrolyte phase (typically a lithium salt dissolved in a solvent). or sodium salt; also not shown in FIG. Similarly, a semi-solid cathode contains a cathode active material, an electrolyte, and conductive additives (including conductive filaments) that form a 3D network of electron-conducting pathways 242 .

Another preferred embodiment of the present invention, shown in FIG. It is an alkali metal cell with a solid cathode 284 and a separator or ion conducting membrane 282 . The semi-solid cathode 284 comprises a cathode active material 272 ₍ e.g., LiCoO2 particles), an electrolyte phase 274 (typically containing lithium or sodium salts dissolved in a solvent), and a 3D network of electronic conduction pathways 270. and a conductive additive phase (containing conductive filaments) that forms a The present invention also includes lithium ion capacitors and sodium ion capacitors.

The electrolyte is preferably a semi-solid electrolyte containing a lithium or sodium salt dissolved in a liquid solvent, the salt concentration of which is 2.5M or more, preferably more than 3M, more preferably more than 3.5M, and even Preferably above 5M, even more preferably above 7M, even more preferably above 10M. In certain embodiments, the electrolyte is a semi-solid electrolyte containing a lithium or sodium salt dissolved in a liquid solvent at a salt concentration of 3.0M to 14M. Selection of the lithium or sodium salt and liquid solvent is further discussed in a later section.

Both the semi-solid anode and the semi-solid cathode preferably have a thickness greater than 200 μm (preferably greater than 300 μm, more preferably greater than 400 μm, even more preferably greater than 500 μm, even more preferably greater than 800 μm, more preferably greater than 1 mm). and may be 5 mm, 1 cm, or even thicker). There is no theoretical limit to the thickness of the electrodes according to the invention. In cells of the invention, the anode active material typically comprises 20 mg/cm ² or more (more typically and preferably 25 mg/cm ² or more, more preferably 30 mg/cm ² or more) in the anode. constitute the active material loading. When an inorganic material is the cathode active material, the cathode active material has an electrode active material loading of 45 mg/cm ² or more (typically and preferably greater than 50 mg/cm ² , more preferably greater than 60 mg/cm ² ). (25 mg/cm ² or more for organic or polymeric cathode active materials).

In such a configuration (FIGS. 1(C)-1(D)), electrons need only travel a short distance (eg, a few micrometers) before being collected by the conductive filament. Conductive filaments constitute a 3D network of electron-conducting pathways and are ubiquitous throughout the quasi-solid electrode (anode or cathode). In addition, all electrode active material particles are pre-dispersed in liquid electrolyte (no wettability issues) and are commonly found in electrodes prepared by conventional processes of wet coating, drying, packing, and electrolyte infusion. Eliminate existing dry pockets. Thus, the process or method according to the invention has a completely unexpected advantage over conventional battery cell manufacturing processes.

These conductive filaments (such as carbon nanotubes and graphene sheets) are bulk filaments that are originally irregularly aggregated before being mixed with the particles of active material and electrolyte as supplied. The mixing procedure involves dispersing these conductive filaments in a high viscosity electrolyte containing particles of active material. This is not as easy a task as it sounds. Diffusion of nanomaterials (particularly nanofilament materials such as carbon nanotubes, carbon nanofibers, and graphene sheets) in highly mobile (non-viscous) liquids is known to be very difficult, let alone at high loadings. of course in highly viscous quasi-solids such as electrolytes containing active materials such as Si nanoparticles for the anode and solid particles such as lithium cobaltate for the cathode. In some preferred embodiments, this problem is exacerbated by the fact that the electrolyte itself is a semi-solid electrolyte and contains high concentrations of lithium or sodium salts in the solvent.

In some preferred embodiments, the electrolyte contains an alkali metal (lithium salt and/or sodium salt) dissolved in an organic or ionic liquid solvent with a sufficiently high alkali metal salt molar ratio, so that the electrolyte is , a vapor pressure less than 0.01 kPa, or less than 0.6 (60%) of the vapor pressure of the solvent alone (when measured at 20° C.), a flash point at least 20° C. higher than the flash point of the first organic liquid solvent alone (in the absence of a lithium salt) or exhibit a flash point above 150° C. or no detectable flash point at all.

Most surprising and of great scientific and technical importance is that if a sufficiently large amount of an alkali metal salt is added to this organic solvent and dissolved to form a solid-like or quasi-solid electrolyte, It is the inventors' discovery that the flammability of any volatile organic solvent can be effectively suppressed. In general, such semi-solid electrolytes are less than 0.01 kPa and often less than 0.001 kPa (when measured at 20°C), and less than 0.1 kPa and often less than 0.01 kPa (100°C (when no alkali metal salt is dissolved in the solvent, the vapor pressure of the corresponding neat solvent is typically much higher). In many cases the vapor molecules are actually too few to be detected.

A very important observation is the high solubility of alkali metal salts in otherwise highly volatile solvents (typically greater than 0.2, more typically greater than 0.3, and many A large molecular ratio or mole fraction of the alkali metal salt, sometimes greater than 0.4, or even greater than 0.5, allows the amount of volatile solvent molecules to escape into the vapor phase at thermodynamic equilibrium. can be dramatically reduced. In many cases, this effectively prevents flammable solvent gas molecules from flaming, even at very high temperatures (eg using a torch). The flash point of the semi-solid electrolyte is typically at least 20 degrees (often more than 50 degrees, or more than 100 degrees) higher than the flash point of the neat organic solvent alone. In most cases the flash point is higher than 150° C. or the flash point cannot be detected. Electrolytes do not ignite. Furthermore, accidental flame outbreaks do not last longer than a few seconds. This is a very significant finding given the view that fire and explosion concerns are major obstacles to the widespread acceptance of battery-powered electric vehicles. This new technology could go a long way in accelerating the emergence of a vibrant EV industry.

From the point of view of basic chemical principles, the addition of solute molecules to a liquid raises the boiling point of the liquid and lowers its vapor pressure and freezing point temperature. These phenomena, like permeability, depend only on solute concentration and not on its type and are called colligative properties of solutions. The original Raoult's law gives the relationship between the ratio of the vapor pressure of a solution (p _s ) to the vapor pressure of a pure liquid (p) and the mole fraction of a solute (x).
p _s /p=e ^−x formula (1a)
For dilute solutions, x<<1, so e ^−x ≈1−x. Thus, in the special case of low solute mole fractions, a more general form of Raoult's law is obtained.
p _s /p=1−x formula (1b)

To determine whether the classical Raoult's law can be applied to predict the vapor pressure of electrolytes at high concentrations, we studied a wide variety of alkali metal salt/organic solvent combinations. I got down to it. Some examples of the results of our studies are summarized in FIGS. 2(A)-2(D), in which experimental p The _s /p values are plotted as a function of molecular ratio (molar fraction, x). For comparison, a curve based on classical Raoult's law, equation (1a) is also plotted. For all types of electrolytes, the p _s /p value follows Raoult's law predictions until the mole fraction x reaches about 0.2, after which the vapor pressure drops rapidly to essentially zero. (almost undetectable). When the vapor pressure is below the threshold, there is no ignition and the present invention provides a superior platform materials chemistry approach to effectively suppress flame generation.

Although deviations from Raoult's law are not uncommon in science, this type of curve for p _s /p values has not been observed for binary solution systems. In particular, due to safety considerations, there have been no reported studies on the vapor pressure of ultra-high concentration battery electrolytes (where the molecular fraction of the alkali metal salt is high, e.g., greater than 0.2, or greater than 0.3). rice field. This is completely unexpected and of the highest technical and scientific importance.

Furthermore, we show that the presence of a 3D network of electronic conduction pathways constituted by conducting nanofilaments acts to further lower the threshold concentration of alkali metal salt required to suppress the critical vapor pressure. I discovered that unexpectedly.

Another surprising element of the present invention is that nearly all types of battery grade organic solvents commonly used to produce semi-solid electrolytes suitable for use in rechargeable alkali metal batteries The idea is that high concentrations of alkali metal salts can be dissolved. Expressed in more easily understandable terms, this concentration is typically greater than 2.5M (moles/liter), more typically and more preferably greater than 3.5M, even more typically and More preferably above 5M, even more preferably above 7M and most preferably above 10M. At salt concentrations of 2.5 M and above, the electrolyte is no longer a liquid electrolyte, but a quasi-solid electrolyte. In the field of lithium or sodium batteries, such high concentrations of alkali metal salts in the solvent are generally considered impossible and undesirable. However, the inventors have found that these quasi-solid electrolytes are surprisingly good for both lithium and sodium batteries in terms of significantly improved safety (non-flammability), improved energy density, and improved power density. was found to be an excellent electrolyte.

In general, the vapor pressure of a solution cannot be directly and easily predicted from concentration values in units of M (moles/liter). Instead, for alkali metal salts, the Raoult's law molecular ratio x is the sum of the molar fractions of positive and negative ions, which depends on the degree of dissociation of the metal salt in a particular solvent at a given temperature. Proportional. Moles/liter concentration does not provide adequate information to allow prediction of vapor pressure.

Generally, in organic solvents used in battery electrolytes, such high concentrations of alkali metal salts (e.g., x=0.3 ~0.7) was not possible. After extensive and in-depth research, we found that (a) first, a highly volatile co-solvent was used to increase the amount of alkali metal salt dissolved in the solvent mixture, and then ( b) We have further discovered that the apparent solubility of alkali metal salts in certain solvents can be significantly increased if this volatile co-solvent is partially or completely removed after the dissolution procedure is completed. Quite unexpectedly, removal of this co-solvent typically did not result in precipitation or crystallization of the alkali metal salt from the solution, even when the solution was highly supersaturated. This new and unique approach produced a material state in which most of the solvent molecules were trapped or held in place by non-volatile alkali metal salt ions (indeed, lithium/sodium salts appear to be solids). I can see Therefore, very few volatile solvent molecules are able to escape to the vapor phase, so there are very few "flammable" gas molecules to help start or sustain a flame. This has not been suggested as technically possible or feasible in the prior art of Na, K, or Li metal batteries.

Furthermore, those skilled in the field of chemistry or materials science believe that such a high salt concentration should cause the electrolyte to behave like a solid with a very high viscosity, and thus the electrolyte should be free of alkali metal ions inside. It was expected that it should be less susceptible to fast diffusion. As a result, alkali metal batteries containing such solid-like electrolytes do not and cannot exhibit high capacities at high charge/discharge rates or under conditions of high current densities (i.e., batteries with low rate capability) would have been expected by those skilled in the art. Contrary to these expectations by ordinary and even skilled practitioners, all alkali metal cells containing such quasi-solid electrolytes provide high energy densities and high power densities over long cycle life spans. The quasi-solid electrolytes devised and disclosed herein are believed to contribute to facile alkali metal ion transport. This surprising observation is believed to be due to two main factors: one factor is related to the internal structure of the electrolyte and the other is related to a high Na ⁺ or Li ⁺ ion transference number (TN), which are discussed further in later sections of this specification.

Without wishing to be bound by any theory, the internal structure of three fundamentally different types of electrolytes can be visualized, as in FIGS. 3(A)-3(C). FIG. 3(A) schematically shows the dense and highly ordered structure of a typical solid electrolyte, which has little free volume for diffusion of alkali metal ions. Movement of ions in such crystal structures is very difficult, resulting in extremely low diffusion coefficients (10 ⁻¹⁶ to 10 ⁻¹² cm ² /sec) and very low ionic conductivities (typically 10 ⁻⁷ S/cm to 10 ⁻⁴ S/cm). In contrast, as shown schematically in FIG. 3(B), the internal structure of a liquid electrolyte is completely amorphous and has a large fraction of free volume through which cations ( Li ⁺ or Na ⁺ ) can easily migrate, have high diffusion coefficients (10 ⁻⁸ to 10 ⁻⁶ cm ² /sec) and high ionic conductivities (typically 10 ⁻³ S/cm ^{∼10 −2} S/cm). However, liquid electrolytes containing low concentrations of alkali metal salts are also flammable and prone to dendrite formation, creating a fire and explosion hazard. Schematically shown in FIG. 3(C) is a quasi-solid containing solvent molecules that separate salts to produce amorphous regions in which free (unclustered) cations can readily migrate. Disordered or amorphous structure of the electrolyte. Such structures tend to achieve high ionic conductivity values (typically 10 ⁻⁴ S/cm to 8×10 ⁻³ S/cm) and still remain non-flammable. Solvent molecules are relatively few and these molecules are held back (prevented from evaporating) by a predominance of salts and a network of conducting filaments.

As a second factor, typical values of 0.1 to We have found that semi-solid electrolytes provide a TN greater than 0.3 (typically in the range of 0.4-0.8), as opposed to 0.2. As shown in FIGS. 4(A)-4(D), the Na ⁺ ion transference number in low salt electrolytes increases as the concentration increases from x=0 to x=0.2-0.35. descend. However, when the molecular ratio exceeds x=0.2-0.35, the transference number increases with increasing salt concentration, indicating a fundamental change in the Na ⁺ or Li ⁺ ion transport mechanism. Again, without wishing to be bound by theory, we provide the following scientifically valid explanation using Na ⁺ ions as an example (similar explanations apply to Li ⁺ ions) . As Na ⁺ ions move in low salt electrolytes (eg, x<0.2), each Na ⁺ ion entrains one or more solvate molecules with it. If the fluid viscosity is increased (ie, when more salt is added to the solvent), coordinated movement of such clusters of charged species may be further impeded.

Fortunately, when very high concentrations of Na salts (eg, x>0.3) are present, Na ⁺ ions can greatly outnumber the available solvating species or solvent molecules. Such solvating species or solvent molecules can otherwise cluster lithium ions, forming multi-component complex species and slowing the diffusion process of Na ⁺ ions. This high Na ⁺ ion concentration makes it possible to have more “free Na ⁺ ions” (those that are not clustered and act alone), which leads to a high Na ⁺ transference number (thus easily Na ⁺ transport) is obtained. In other words, the sodium ion transport mechanism transitions from a multi-ion complex-dominated mechanism (with a larger hydrodynamic radius) to a single-ion-dominated mechanism with a large number of available free Na ⁺ ions (with a smaller hydrodynamic radius). have). Furthermore, this observation argues that Na ⁺ ions can act on the quasi-solid electrolyte without compromising the rate capability of the Na metal cell. Nevertheless, these highly concentrated electrolytes are non-flammable and safe. The combination of these features and advantages for battery applications has not been taught or only hinted at in any previous reports. Next, the theoretical aspects of the ionic transference numbers of quasi-solid electrolytes are presented below.

In selecting an electrolyte system for a battery, the ionic conductivity of lithium ions or sodium ions is an important factor to consider. The ionic conductivity of Na ⁺ ions in organic liquid-based electrolytes is on the order of 10 ⁻³ to 10 ⁻² S/cm, and in solid state electrolytes it is typically 10 ⁻⁷ to 10 ⁻⁴ It is within the range of S/cm. Due to their low ionic conductivity, solid-state electrolytes have not been widely used in battery systems. This is unfortunate because solid state electrolytes are resistant to dendrite intrusion in alkali metal secondary cells. In contrast, the ionic conductivity of our quasi-solid electrolytes is typically in the range of 10 ⁻⁴ to 8×10 ⁻³ S/cm, which is sufficient for use in rechargeable batteries. be.

Ionic mobility or diffusion coefficients are not the only important transport parameters for battery electrolytes. Separate transference numbers for cations and anions are also important. For example, ion mobility is reduced when viscous liquids are used as electrolytes in alkali metal batteries. Therefore, a high transference number of alkali metal ions in the electrolyte is required to achieve high ionic conductivity.

Ion transport and diffusion in liquid electrolytes consisting of only one type of cation (e.g. Na ⁺ ) and only one type of anion and a liquid solvent or a mixture of two liquid solvents has been demonstrated by AC impedance spectroscopy and pulsed field gradients. It can be studied by NMR techniques. AC impedance provides information on overall ionic conductivity, and NMR allows determination of individual self-diffusion coefficients of cations and anions. In general, the self-diffusion coefficient of cations is slightly higher than that of anions. Typically, the Haven ratio resulting from the diffusion coefficient and overall ionic conductivity is in the range of 1.3 to 2 and ion pairs or ion complexes (e.g. Na ⁺ solvates It was found that the transport of (clusters of ) was shown to be an important feature in electrolytes containing low salt concentrations.

The situation is further complicated when either two different alkali metal salts or one ionic liquid (alkali metal salt or liquid solvent) is added to the electrolyte, resulting in a solution containing at least three or four ions. In this case it is advantageous to use, as an example, an alkali metal salt containing the same anion as in the solvated ionic liquid. This is due to the higher amount of alkali metal salt that is soluble than in mixtures with dissimilar anions. Therefore, the next logical question is whether it is possible to improve the transference number of Na ⁺ (or Li ⁺ ) by dissolving more sodium (or lithium) salt in the liquid solvent. be.

The relationship between the overall ionic conductivity σdc of a tri-ionic liquid mixture and the individual diffusion coefficients Di of the ions can be given by the Nernst-Einstein equation.
σ _dc = (e ² /k _B TH _R ) [(N _Na ⁺ ) (D _Na ⁺ ) + (N _E ⁺ ) (D _E ⁺ ) + (N _B ⁻ ) (D _B ⁻ )] Equation (2)
where e and kB denote the elementary charge and Boltzmann's constant, respectively, and Ni is the number density of individual ions (Na ⁺ , Li ⁺ , ClO ₄ ⁻ , etc.). The Haven ratio _HR takes into account the cross-correlations between the migration of different types of ions.

Simple ionic liquids containing only one type of cation and anion are characterized by Haven ratios typically in the range of 1.3 to 2.0. A Haven ratio greater than 1 indicates that ions of different charge preferentially move in the same direction (ie ion transport as pairs or clusters). Evidence of such ion pairs can be found using Raman spectra of various electrolytes. Values for Haven ratios in tri-ion mixtures are in the range of 1.6 to 2.0. The slightly higher _HR values compared to electrolytes with x=0 indicate that pairing is more pronounced in the mixture.

For the same mixture, the overall ionic conductivity of the mixture decreases with increasing alkali metal salt content x. This decrease in conductivity is directly related to the decrease in the individual self-diffusion coefficients of all ions. Our studies on various mixtures of ionic liquids and alkali metal salts show that the viscosity increases with increasing salt content x. These findings suggest that the addition of alkali metal salts leads to stronger ionic bonding in the liquid mixture, which slows the liquid dynamic behavior. This may be due to the stronger Coulombic interactions between small sodium (or lithium) ions and anions than the Coulombic interactions between larger organic cations and anions. Therefore, the decrease in ionic conductivity with increasing alkali metal salt content x is not due to a decrease in the number density of mobile ions, but due to a decrease in ion mobility.

To analyze the individual contributions of cations and anions to the overall ionic conductivity of a mixture, the apparent transference number t _i can be defined by the following equation.
t _i =N _i Di/(ΣN _i Di) Equation (3)
As an example, N-butyl-N-methyl-pyrrolidinium bis(trifluoromethanesulfonyl)imide (BMP-TFSI) containing Na ⁺ , BMP ⁺ , and TFSI ⁻ ions and sodium bis(trifluoromethanesulfonyl)imide (Na -TFSI), the apparent lithium transference number _tLi increases with increasing Na-TFSI content. That is, t _Na =0.242 at x=0.34 (for t _Na <0.1 at x<0.2), D _Na ≈0.7D _TFSI and D _BMP ≈1.6D _TFSI . The main reason for the higher apparent Na ⁺ transference number in the mixture is the higher number density of Na ⁺ ions.

To further increase the sodium transport number in such mixtures, the number density and/or diffusion coefficient of sodium ions must be further increased relative to other ions. A further increase in Na ⁺ ion number density would be expected to be very difficult, as mixtures tend to undergo salt crystallization or precipitation at high Na salt contents. The present invention overcomes this problem. The inventors have surprisingly found that the addition of a very small proportion of highly volatile organic liquids (e.g. ether-based solvents) can significantly reduce Na or We have observed that the solubility limit of Li salts can be significantly increased (e.g., typically from x<0.2 to x>0.3-0.6, or typically from 1M to >5M ). This can be achieved with a ratio of ionic liquid (or viscous organic liquid) to volatile organic solvent as high as 10:1, thus keeping the volatile solvent content to a minimum and the electrolyte Minimize potential flammability.

The diffusion coefficient of ions measured in pulsed field gradient NMR (PFG-NMR) experiments depends on the effective radius of the diffuser. Due to the strong interaction between Na ⁺ ions and TFSI ⁻ ions, Na ⁺ ions form [Na(TFSI) _n+1 ] ^n- complexes. Coordination numbers up to n+1=4 for alkali metal ions have been observed. The coordination number determines the effective hydrodynamic radius of the complex and thus the diffusion coefficient in liquid mixtures. Using the Stokes-Einstein equation Di=k _B T/(cπηr _i ), the effective hydrodynamic radius ri of the diffuser can be calculated from its diffusion coefficient Di. The constant c varies from 4 to 6 depending on the shape of the diffuser. A comparison of the effective hydrodynamic radii of cations and anions in ionic liquids with their van der Waals radii reveals that, in general, the c-values for cations are lower than those for anions. For EMI-TFSI/Na-TFSI mixtures, the hydrodynamic radius for Na is in the range of 0.9-1.3 nm. This is generally the van der Waals radius of the [Na(TFSI) ₂ ] ^- and [Na(TFSI) ₃ ] ^2- complexes. For the BMP-TFSI/Na-TFSI mixture with x=0.34, r _BMP ≈0.55 nm, and assuming the same c-value for BMP ⁺ and diffuse Na complexes, The effective hydrodynamic radius is r _Na =(D _BMP /D _Na )r _BMP ≈1.3 nm. This value for r _Na suggests that the sodium coordination number in the diffusion complex is at least 2 for mixtures containing low salt concentrations.

Most sodium ions should diffuse as [Na(TFSI) ₂ ] ^-complexes , since the number of TFSI ⁻ ions is not high enough to produce significant amounts of [Na(TFSI) ₃ ] ^2- complexes. be. On the other hand, when higher Na salt concentrations are achieved without crystallization (e.g. in our semi-solid electrolyte), the mixture contains significant amounts of neutral [Na(TFSI)] complexes. These complexes should be relatively small (r[Na(TFSI)]≈0.5 nm) and have higher diffusivities. Therefore, higher salt concentrations should not only increase the number density of sodium ions, but also increase the diffusion coefficient of diffusing sodium complexes compared to organic cations. The above analysis is applicable to electrolytes containing either organic liquid solvents or ionic liquid solvents and both lithium and sodium ions. In all cases, when the alkali metal salt concentration is above the threshold, further increases in concentration increase the number of free or unclustered alkali metal ions that migrate between the anode and cathode, resulting in provides an appropriate amount of alkali metal ions required for the intercalation/deintercalation or chemical reaction of

In addition to the non-flammability and high alkali metal ion transference numbers discussed above, there are several additional benefits associated with the use of semi-solid electrolytes according to the present invention. As an example, semi-solid electrolytes can significantly improve the cycle performance and safety performance of rechargeable alkali metal batteries by effectively suppressing dendrite growth. It is generally accepted that dendrites begin to grow in non-aqueous liquid electrolytes when anions are depleted near the electrode where plating occurs. In ultra-high concentration electrolytes, there is a large amount of anions to balance the cations (Li ⁺ or Na ⁺ ) and anions near the metallic sodium anode. Furthermore, the space charge generated by anion depletion is minimal and does not contribute to dendrite growth. Furthermore, due to both the ultra-high Na salt concentration and the high Na ion transference number, the semi-solid electrolyte provides a large amount of available sodium ion flux, increasing the sodium ion mass transfer rate between the electrolyte and the sodium electrode. , thereby improving the uniformity and dissolution of sodium deposition during the charge/discharge process. In addition, the high local viscosity induced by high concentrations can increase the pressure from the electrolyte and inhibit dendrite growth, resulting in more uniform deposition on the surface of the anode. Also, high viscosity can limit anion convection near the deposition area, promoting more uniform deposition of sodium ions. The same reasoning applies to lithium metal batteries. These reasons, individually or in combination, are believed to support the observation that no dendrite-like features are observed in any of the many rechargeable alkali metal cells we have examined thus far.

In preferred embodiments, the anode active material is pure graphene, graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide, graphene hydride, graphene nitrogen, graphene chemically functionalized, or Prelithiated versions of graphene sheets selected from combinations thereof. Starting graphene materials for making any one of the above graphene materials include natural graphite, synthetic graphite, mesophase carbon, mesophase pitch, mesocarbon microbeads, soft carbon, hard carbon, coke, carbon fiber, carbon nanofiber , carbon nanotubes, or combinations thereof. Graphene materials are also good conductive additives for both anode and cathode active materials in lithium batteries.

Assuming that interplanar van der Waals forces can be overcome, the constituent graphene planes of graphite crystals in natural or artificial graphite particles can be exfoliated and extracted or isolated to form individual graphenes of hexagonal carbon atoms. Sheets can be obtained and these sheets are a single atom thick. An isolated individual graphene plane of carbon atoms is commonly referred to as monolayer graphene. A stack of multiple graphene planes joined by van der Waals forces with a graphene plane spacing of about 0.3354 nm in the thickness direction is commonly referred to as multi-layer graphene. Multilayer graphene platelets have up to 300 graphene planes (thickness less than 100 nm), but more typically up to 30 graphene planes (thickness less than 10 nm), even more typically up to 20 layers. It has graphene planes (thickness less than 7 nm), and most typically up to 10 layers of graphene planes (commonly referred to in the scientific community as few-layer graphene). Single-layer graphene and multi-layer graphene sheets are collectively referred to as “nanographene platelets” (NGP). Graphene sheets/platelets (collectively NGP) are a new class of carbon nanomaterials (2D nanocarbons) distinct from 0D fullerenes, 1D CNTs or CNFs, and 3D graphite. For the purposes of defining the claims, and as commonly understood in the art, graphene materials (isolated graphene sheets) are not carbon nanotubes (CNT) or carbon nanofibers (CNF). ).

In one method, graphene material is obtained by intercalating natural graphite particles with strong acids and/or oxidizing agents to obtain graphite intercalation compound (GIC) or graphite oxide (GO), as shown in FIG. obtained by The presence of chemical species or functional groups in the interstitial space between graphene planes in GIC or GO serves to increase the graphene spacing (d ₀₀₂ ; determined by X-ray diffraction), thereby This greatly reduces the van der Waals forces that hold the graphene planes together along the c-axis direction. GIC or GO is most often produced by soaking natural graphite powder in a mixture of sulfuric acid, nitric acid (an oxidizing agent), and another oxidizing agent such as potassium permanganate or sodium perchlorate. . When an oxidizing agent is present during the intercalation procedure, the resulting GIC is actually a type of graphite oxide (GO) particles. The GIC or GO is then repeatedly washed and rinsed in water to remove excess acid, resulting in a graphite oxide suspension or dispersion that is dispersed in water in discrete, visually distinguishable containing graphite oxide particles. To produce graphene material, one of two processing routes can be followed after this rinsing step, briefly described below.

Route 1 involves removing water from the suspension to obtain "expanded graphite" which is essentially a mass of dry GIC or dry graphite oxide particles. When exfoliated graphite is exposed to temperatures typically in the range of 800-1,050° C. for about 30 seconds to 2 minutes, the GIC undergoes a rapid volume expansion of 30-300 times to form "graphite worms." . Each graphite worm (104) is a collection of flakes of graphite that have been exfoliated, but are largely unseparated and remain interconnected.

In Route 1A, these graphite worms (exfoliated graphite or "network of interconnected/unseparated graphite flakes") are recompressed to typically 0.1 mm (100 μm) to 0.5 mm Flexible graphite sheets or foils with thicknesses in the range (500 μm) can be obtained. Alternatively, graphite worms are simply exfoliated using a low-intensity air mill or shears for the purpose of producing so-called "expanded graphite flakes", which mainly contain graphite flakes or platelets thicker than 100 nm (thus not nanomaterials by definition). You can also choose to shred.

In Route 1B, exfoliated as disclosed in commonly assigned U.S. Patent Application Serial No. 10/858,814 (March 6, 2004) (U.S. Patent No. 2005/0271574). Graphite is subjected to high-intensity mechanical shear (e.g., using an ultrasonic device, a high-shear mixer, a high-intensity air jet mill, or a high-energy ball mill) to separate single- and multi-layer graphene sheets (collectively (hereinafter referred to as NGP). Single-layer graphene can be as thin as 0.34 nm, while multi-layer graphene can have a thickness of up to 100 nm, but more typically less than 10 nm (commonly referred to as few-layer graphene). Multiple graphene sheets or platelets may be formed as a sheet of NGP paper using a papermaking process. This NGP paper is an example of a porous graphene structured layer utilized in the method according to the present invention.

Route 2 involves sonicating a graphite oxide suspension (eg, graphite oxide particles dispersed in water) for the purpose of separating/isolating individual graphene oxide sheets from the graphite oxide particles. This shows that the separation of the graphene planes has been increased from 0.3354 nm in natural graphite to 0.6-1.1 nm in highly oxidized graphite oxide, a van der Waals separation that holds adjacent planes together. It is based on the view that it greatly weakens power. The ultrasonic power may be sufficient to further separate the graphene plane sheets to form fully separated, isolated, or discrete graphene oxide (GO) sheets. These graphene oxide sheets can then be chemically or thermally reduced to yield “reduced graphene oxide” (RGO), which typically contains 0.001 wt % to 10 wt %, More typically it has an oxygen content of 0.01% to 5% by weight, and most typically and preferably contains less than 2% by weight oxygen.

For the purposes of defining the claims of this application, NGP or graphene materials include single and multilayer (typically less than 10 layers) pure graphene, graphene oxide, reduced graphene oxide (RGO), graphene fluoride , graphene chloride, graphene bromide, graphene iodide, graphene hydride, graphene nitrogen, chemically functionalized graphene, discrete sheets/platelets of doped (eg, B or N doped) graphene. Pure graphene has essentially 0% oxygen. RGO typically has an oxygen content of 0.001% to 5% by weight. Graphene oxide (including RGO) can have 0.001% to 50% oxygen by weight. Except for pure graphene, all graphene materials contain 0.001% to 50% by weight of non-carbon elements (eg, O, H, N, B, F, Cl, Br, I, etc.). These materials are referred to herein as impure graphene materials.

Pure graphene is produced as smaller, discrete graphene sheets (typically 0.3 μm to 10 μm) by direct sonication (also known as liquid phase exfoliation or generation) or supercritical fluid exfoliation of graphite particles. can do. These methods are well known in the art.

Graphene oxide (GO) is added to the starting graphite material in a reaction vessel at a desired temperature for a period of time (typically 0.5-96 hours depending on the nature of the starting material and the type of oxidant used). can be obtained by immersing a powder or filament of (eg, natural graphite powder) in an oxidizing liquid medium (eg, a mixture of sulfuric acid, nitric acid, and potassium permanganate). As described above, the resulting graphite oxide particles can then be subjected to thermal exfoliation or ultrasonically induced exfoliation to produce isolated GO sheets. These GO sheets can then be transformed into various graphene materials by replacing the OH groups with other chemical groups (such as Br and _NH2 ).

Fluorinated graphene or graphene fluoride is used herein as an example of a group of halogenated graphene materials. There are two different approaches that have been taken to produce fluorinated graphene. (1) Fluorination of pre-synthesized graphene: This approach requires treating graphene prepared by mechanical exfoliation or CVD growth with a fluorinating agent such as XeF2 or F _- based plasma. (2) Exfoliation of multilayer graphite fluoride: both mechanical exfoliation and liquid phase exfoliation of graphite fluoride can be easily achieved.

Graphite intercalation compound (GIC) CxF ( ₂ ≤ _x ≤ 24) is produced at low temperature, whereas the interaction of F2 with graphite at high temperature is covalent graphite fluoride (CF) _n or ( _{C2F)n .} In (CF) _n , the carbon atoms are sp3-hybridized, so the fluorocarbon layers are corrugated and consist of trans-linked cyclohexane chair conformations. In (C ₂ F) _n , only half of the C atoms are fluorinated and any pair of adjacent carbon sheets are linked by C—C covalent bonds. Systematic studies on fluorination reactions show that the obtained F/C ratio depends on the fluorination temperature, the partial pressure of fluorine in the fluorination gas, and the physical properties of the graphite precursor, such as the degree of graphitization, grain size, and ratio. It was shown to strongly depend on the surface area. _In addition to fluorine ₍ F2), other fluorinating agents can be used, but most of the available literature involves fluorination with F2 gas, sometimes in the presence of fluoride.

In order to exfoliate the layered precursor material into individual layers or several layers, it is necessary to overcome the attractive forces between adjacent layers and further stabilize the layers. This may be achieved by covalent modification of the graphene surface with functional groups or by non-covalent modification using specific solvents, surfactants, polymers, or donor-acceptor aromatic molecules. The process of liquid phase exfoliation involves sonication of graphite fluoride in a liquid medium.

Nitridation of graphene can be performed by exposing graphene materials, such as graphene oxide, to ammonia at elevated temperatures (200-400° C.). Nitrogenated graphene can also be produced at lower temperatures by hydrothermal methods. This is done, for example, by sealing the GO and ammonia in an autoclave and then increasing the temperature to 150-250°C. Other methods to synthesize nitrogen-doped graphene include nitrogen plasma treatment on graphene, arc discharge between graphite electrodes in the presence of ammonia, ammonolysis of graphene oxide under CVD conditions, and graphene oxide at various temperatures. and hydrothermal treatment of urea.

There is no limit to the type of anode active material or cathode active material that can be used in the practice of the present invention. Preferably, in a lithium cell according to the present invention, the anode active material is 1. above Li/Li ⁺ (ie relative to Li→Li ⁺ +e ⁻ as standard potential) when the cell is charged. It absorbs lithium ions at electrochemical potentials below 0 volts (preferably below 0.7 volts). In one preferred embodiment, the anode active material for a lithium battery comprises (a) particles of lithium metal or lithium metal alloy; (b) natural graphite particles, synthetic graphite particles, mesocarbon microbeads (MCMB), carbon particles ( (including soft carbon and hard carbon), needle coke, carbon nanotubes, carbon nanofibers, carbon fibers, and graphite fibers; (c) silicon (Si), germanium (Ge), tin (Sn), lead (Pb), Antimony (Sb), Bismuth (Bi), Zinc (Zn), Aluminum (Al), Nickel (Ni), Cobalt (Co), Manganese (Mn), Titanium (Ti), Iron (Fe), and Cadmium (Cd) and (d) alloys or intermetallic compounds of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, or Cd with other elements, stoichiometric or non-stoichiometric (e) oxides, carbides, nitrides, sulfides of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ni, Co, Ti, Mn, or Cd; phosphides, selenides, and tellurides, and mixtures or composites thereof; (f) prelithiated versions thereof; (g) prelithiated graphene sheets; Selected from the group.

In certain embodiments, the alkali metal cell is a sodium metal cell or a sodium ion cell and the active material is petroleum coke, carbon black, amorphous carbon, activated carbon, hard carbon (difficult to graphitize carbon), soft carbon ( readily graphitizable carbon), template carbon, hollow carbon nanowires, hollow carbon _spheres , _titanates , _{NaTi2 ( PO4} ) ₃ , _{Na2Ti3O7 , Na2C8H4O4 , Na2TP} , Na _x TiO ₂ (x=0.2-1.0), Na ₂ C ₈ H ₄ O ₄ , carboxylic acid-based materials, C ₈ H ₄ Na ₂ O ₄ , C ₈ H ₆ O ₄ , C _{8 sodium intercalate selected from H5NaO4 , C8Na2F4O4 , C10H2Na4O8 , C14H4O6 , C14H4Na4O8 , or combinations thereof} It is an anode active material containing an ion compound.

In certain embodiments, the alkali metal cell is a sodium metal cell or a sodium ion cell and the active material is an anode active material selected from the group consisting of: (a) particles of sodium metal or sodium metal alloy; (b) natural graphite particles, synthetic graphite particles, mesocarbon microbeads (MCMB), carbon particles, needle coke, carbon nanotubes, carbon nanofibers, carbon fibers, and graphite fibers; (c) sodium-doped silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al); , titanium (Ti), cobalt (Co), nickel (Ni), manganese (Mn), cadmium (Cd), and mixtures thereof; and (d) Si, Ge, Sn, Pb, Sb, Bi, Zn, Al (e) Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ti, Co, sodium-containing oxides, carbides, nitrides, sulfides, phosphides, selenides, tellurides, or antimonides of Ni, Mn, Cd, and mixtures or composites thereof; (f) sodium salts; ) graphene sheets preloaded with sodium ions; and combinations thereof.

A wide variety of cathode active materials can be used to implement lithium cells according to the present invention. Cathode active materials are typically lithium intercalating or lithium absorbing compounds capable of storing lithium ions when the lithium battery is discharged and releasing the lithium ions to the electrolyte when recharged. . Cathode active materials can be selected from inorganic materials, organic or polymeric materials, metal oxides/phosphates/sulfides (the most desirable type of inorganic cathode materials), or combinations thereof such as:

lithium cobaltate, lithium nickelate, lithium manganate, lithium vanadate, lithium transition metal oxide, lithium mixed metal oxide, lithium iron phosphate, lithium manganese phosphate, lithium vanadium phosphate, lithium mixed metal phosphate, The group of metal oxides, metal phosphates and metal sulfides consisting of transition metal sulfides and combinations thereof. _{In particular} , _{lithium vanadate is VO2 , LixVO2 , V2O5 , LixV2O5 , V3O8} , _LixV3O8 , _{LixV3O7 , V4O9} , Li _x V ₄ O ₉ , V ₆ O ₁₃ , Li _x V ₆ O ₁₃ , doped versions thereof, derivatives thereof, and combinations thereof, where 0 .1<x<5). The lithium transition metal oxide is a layered compound _LiMO2 , a _spinel compound _LiM2O4 , an olivine compound _LiMPO4 , a silicate compound _Li2MSiO4 , a taborite compound _LiMPO4F , a borate compound _{LiMBO3 ,} or combinations thereof. where M is a transition metal or a mixture of transition metals.

Other inorganic materials for use as cathode active materials may be selected from sulfur, sulfur compounds, lithium polysulfides, transition metal dichalcogenides, transition metal trichalcogenides, or combinations thereof. In particular, the inorganic material is selected from _TiS2 , _TaS2 , MoS2, _NbSe3 , _{MnO2 , CoO2} , iron oxide, vanadium oxide, or combinations thereof. These are discussed further below.

In particular, the inorganic materials are (a) bismuth selenide or bismuth telluride, (b) transition metal dichalcogenides or trichalcogenides, (c) niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, cobalt, manganese, iron , nickel, or transition metal sulfides, selenides, or tellurides, (d) boron nitride, or (e) combinations thereof.

Organic or polymeric materials include poly(anthraquinonyl sulfide) (PAQS), lithium oxocarbon, 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA), poly(anthraquinonyl sulfide), pyrene -4,5,9,10-tetraone (PYT), polymer-bound PYT, quino (triazene), redox-active organic material, tetracyanoquinodimethane (TCNQ), tetracyanoethylene (TCNE), 2,3,6 ,7,10,11-hexamethoxytriphenylene (HMTP), poly(5-amino-1,4-dihydroxyanthraquinone) (PDAQ), phosphazene disulfide polymer ([(NPS ₂ ) ₃ ]n), lithiated 1 , 4,5,8-naphthalenetetraol formaldehyde polymer, hexaazatrinaphthylene (HATN), hexaazatriphenylene hexacarbonitrile (HAT(CN) ₆ ), 5-benzylidenehydantoin, isatin lithium salt, pyromellitic diimide lithium salt, tetrahydroxy-p-benzoquinone derivative (THQLi ₄ ), N,N'-diphenyl-2,3,5,6-tetraketopiperazine (PHP), N,N'-diallyl-2,3,5,6 - tetraketopiperazine (AP), N,N'-dipropyl-2,3,5,6-tetraketopiperazine (PRP), thioether polymer, quinone compound, 1,4-benzoquinone, 5,7,12,14- pentcentetron (PT), 5-amino-2,3-dihydro-1,4-dihydroxyanthraquinone (ADDQ), 5-amino-1,4-dihydroxyanthraquinone (ADAQ), calixquinone, Li ₄ C ₆ O ₆ , It may be _selected from _Li2C6O6 , _{Li6C6O6 ,} or _{combinations thereof} .

Thioether polymers include poly[methantetriyl-tetra(thiomethylene)] (PMTTM), poly(2,4-dithiopentanylene) (PDTP), poly(ethene-1,1,2,2-tetrathiol as backbone thioether polymer ) (PETT), a side-chain thioether polymer with a backbone composed of conjugated aromatic moieties and pendant thioether side chains, poly(2-phenyl-1,3-dithiolane) (PPDT), poly( 1,4-di(1,3-dithiolan-2-yl)benzene) (PDDTB), poly(tetrahydrobenzodithiophene) (PTHBDT), poly[1,2,4,5-tetrakis(propylthio)benzene] ( PTKPTB, or poly[3,4(ethylenedithio)thiophene] (PEDTT).

Organic materials include copper phthalocyanine, zinc phthalocyanine, tin phthalocyanine, iron phthalocyanine, lead phthalocyanine, nickel phthalocyanine, vanadyl phthalocyanine, fluorochrome phthalocyanine, magnesium phthalocyanine, manganese phthalocyanine, dilithium phthalocyanine, phthalocyanine chloroaluminum, cadmium phthalocyanine, chlorogallium phthalocyanine, Phthalocyanine compounds selected from cobalt phthalocyanines, silver phthalocyanines, metal-free phthalocyanines, chemical derivatives thereof, or combinations thereof.

The lithium intercalating compound or lithium absorbing compound may be selected from metal carbides, metal nitrides, metal borides, metal dichalcogenides, or combinations thereof. Preferably, the lithium intercalating compound or lithium absorbing compound comprises niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, vanadium, chromium, cobalt, in the form of nanowires, nanodiscs, nanoribbons, or nanoplatelets. It is selected from manganese, iron or nickel oxides, dichalcogenides, trichalcogenides, sulfides, selenides or tellurides.

The inventors have discovered that a wide variety of two-dimensional (2D) inorganic materials can be used as cathode active materials in lithium batteries according to the invention prepared by the direct active material-electrolyte injection method according to the invention. Layered materials provide a variety of sources for 2D systems that can exhibit unexpected electronic properties and good affinity for lithium ions. Graphite is the best-known layered material, but transition metal dichalcogenides (TMDs), transition metal oxides (TMOs), and a wide range of other compounds such as BN _{, Bi2Te3 ,} and _Bi2Se3 can also be a source of 2D material.

Preferably, the lithium intercalating compound or lithium absorbing compound is (a) bismuth selenide or bismuth telluride, (b) a transition metal dichalcogenide or trichalcogenide, (c) niobium, zirconium, molybdenum, hafnium, tantalum, tungsten , titanium, cobalt, manganese, iron, nickel, or transition metal sulfides, selenides, or tellurides; (d) boron nitride; or (e) combinations thereof. Platelets, nanocoatings or nanosheets, wherein the discs, platelets or sheets have a thickness of less than 100 nm. Lithium intercalating compounds or lithium absorbing compounds include (i) bismuth selenide or bismuth telluride, (ii) transition metal dichalcogenides or trichalcogenides, (iii) niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, nanodiscs, nanoplatelets, nanodiscs of compounds selected from cobalt, manganese, iron, nickel, or transition metal sulfides, selenides, or tellurides, (iv) boron nitride, or (v) combinations thereof Coatings or nanosheets may be included, where the discs, platelets, coatings or sheets have a thickness of less than 100 nm.

In rechargeable sodium cells, the cathode active materials are _{NaFePO4 (} sodium iron phosphate), _Na0.7FePO4 , _{Na1.5VOPO4F0.5 , Na3V2 ( PO4} ) _{3 ,} Na _{3V2 ( PO4} ) _2F3 , _Na2FePO4F , _{NaFeF3 , NaVPO4F , Na3V2 ( PO4 ) 2F3 , Na1.5VOPO4F0.5 , Na3V 2 (} PO4) ₃ , _NaV6O15 , _NaxVO2 , _Na0.33V2O5 , _{NaxCoO2 (} sodium cobalt oxide), Na2 _{/3 [ Ni1 / 3Mn2 / 3} ]O2 _, Nax( _{Fe1 / 2Mn1 /2 ) O2} , _{NaxMnO2 (} sodium manganese bronze), _Na0.44MnO2 , _Na0.44MnO2 / _C , _{Na4Mn9O 18} , _NaFe2Mn ( _PO4 ) ₃ , _{Na2Ti3O7 , Ni1} / _3Mn1 / _3Co1 / _3O2 , _{Cu0.56Ni0.44HCF (} copper and nickel _{hexacyanoferrate} ) , _{NiHCF (} nickel hexacyanoferrate), _NaxCoO2 , _{NaCrO2 , Na3Ti2 (} PO4) _{3 , NiCo2O4 , Ni3S2} /FeS2, _Sb2O4 , _{Na4Fe (} CN ) 6/C, NaV _1-x Cr _x PO ₄ F, SeySz (selenium and selenium/sulphur, z/y from 0.01 to 100), Se (no S), aluordite, or combinations thereof May contain sodium intercalation compounds.

Alternatively, the cathode active material may be selected from functional or nanostructured materials having alkali metal ion trapping functional groups or alkali metal ion storage surfaces in direct contact with the electrolyte. Preferably, the functional group reacts reversibly with alkali metal ions, forms redox pairs with alkali metal ions, or forms chemical complexes with alkali metal ions. The functional or nanostructured material is (a) soft carbon, hard carbon, polymeric carbon or carbonized resin, mesophase carbon, coke, carbonized pitch, carbon black, activated carbon, nanocellular carbon foam, or partially graphitized (b) nano-graphene platelets selected from single-walled graphene sheets or multi-walled graphene platelets; and (c) from single-walled carbon nanotubes or multi-walled carbon nanotubes. (d) carbon nanofibers, nanowires, metal oxide nanowires or fibers, conducting polymer nanofibers, or combinations thereof; (e) carbonyl-containing organic or polymeric molecules; (f) carbonyls. functional materials containing , carboxyl, or amine groups; and combinations thereof.

Functional or nanostructured materials include poly(2,5-dihydroxy-1,4-benzoquinone-3,6-methylene), Na _x C ₆ O ₆ (x=1-3), Na ₂ (C ₆ H ₂ O ₄ ), Na ₂ C ₈ H ₄ O ₄ (Na terephthalate), Na ₂ C ₆ H ₄ O ₄ (Na trans-trans-muconate), 3,4,9,10-perylenetetracarboxylic acid-di anhydride (PTCDA) sulfide polymer, PTCDA, 1,4,5,8-naphthalene-tetracarboxylic dianhydride (NTCDA), benzene-1,2,4,5-tetracarboxylic dianhydride, 1 , 4,5,8-tetrahydroxyanthraquinone, tetrahydroxy-p-benzoquinone, and combinations thereof. Desirably, the functional or nanostructured material has functional groups selected from —COOH, ═O, —NH ₂ , —OR, or —COOR, where R is a hydrocarbon radical. .

Single-layer or few-layer (up to 20 layers) non-graphene 2D nanomaterials can be fabricated by several methods as follows. Mechanical ablation, laser ablation (e.g., using laser pulses to ablate the TMD to a monolayer), liquid phase exfoliation, and synthesis of thin film techniques, e.g., PVD (e.g., sputtering), vapor deposition, vapor phase epitaxy, liquid phase epitaxy, chemical vapor deposition epitaxy, molecular beam epitaxy (MBE), atomic layer epitaxy (ALE), and plasma versions thereof.

A wide variety of electrolytes can be used in the practice of the invention. Non-aqueous organic and/or ionic liquid electrolytes are most preferred. Non-aqueous electrolytes employed herein may be produced by dissolving an electrolyte salt in a non-aqueous solvent. Any known nonaqueous solvent that is employed as a solvent for lithium secondary batteries can be employed. A non-aqueous solvent (hereinafter referred to as the second (referred to as the solvent of ) can preferably be employed. The non-aqueous solvent is (a) stable to negative electrodes containing well-formed carbonaceous materials in a graphite structure, (b) effective in inhibiting reduction or oxidative decomposition of the electrolyte, and ( c) It has the advantage of high electrical conductivity. A non-aqueous electrolyte composed only of ethylene carbonate (EC) has the advantage of being relatively stable against decomposition due to reduction by a graphitized carbonaceous material. However, the melting point of EC is relatively high at 39 to 40° C., and the viscosity of EC is relatively high, so the conductivity of EC is low. Therefore, EC alone is used as an electrolyte for secondary batteries that operate below room temperature is inappropriate for The second solvent used in the mixture with EC serves to make the solvent mixture less viscous than EC alone, thereby increasing the ionic conductivity of the mixed solvent. Furthermore, the use of a second solvent having a donor number of 18 or less (ethylene carbonate has a donor number of 16.4) allows the ethylene carbonate to be easily and selectively solvated with lithium ions, thus sufficiently It is hypothesized that the reduction reaction of the second solvent with the carbonaceous material produced by graphitization of 1 is inhibited. Furthermore, when the number of donors in the second solvent is controlled to 18 or less, the oxidative decomposition potential to the lithium electrode can be easily increased to 4 V or more, thereby producing a high voltage lithium secondary battery. becomes possible.

Preferred second solvents are dimethyl carbonate (DMC), methyl ethyl carbonate (MEC), diethyl carbonate (DEC), ethyl propionate, methyl propionate, propylene carbonate (PC), γ-butyrolactone (γ-BL), acetonitrile (AN), ethyl acetate (EA), propyl formate (PF), methyl formate (MF), toluene, xylene, and methyl acetate (MA). These second solvents may be employed alone or in combination of two or more. More desirably, this second solvent should be selected from those having a donor number of 16.5 or less. The viscosity of this second solvent should preferably be no greater than 28 cps at 25°C.

The mixing ratio of the ethylene carbonate in the mixed solvent should preferably be 10-80% by volume. If the mixing ratio of ethylene carbonate is out of this range, the conductivity of the solvent may be lowered, or the solvent tends to decompose more easily, thereby deteriorating the charge-discharge efficiency. A more preferable mixing ratio of ethylene carbonate is 20 to 75% by volume. When the mixing ratio of ethylene carbonate in the non-aqueous solvent is increased to 20% by volume or more, the solvation effect of ethylene carbonate on lithium ions is promoted, and the effect of inhibiting solvent decomposition can be improved.

Examples of preferred mixed solvents are compositions comprising EC and MEC; compositions comprising EC, PC and MEC; compositions comprising EC, MEC and DEC; compositions comprising EC, MEC and DMC; , MEC, PC and DEC, and the volume ratio of MEC is controlled within the range of 30-80%. By selecting the volume ratio of MEC from the range of 30-80%, more preferably 40-70%, the conductivity of the solvent can be improved. For the purpose of suppressing the decomposition reaction of the solvent, an electrolyte with dissolved carbon dioxide can be employed, thereby effectively improving both the capacity and the cycle life of the battery. Electrolyte salts incorporated into the non-aqueous electrolyte include lithium perchlorate (LiClO ₄ ), lithium hexafluorophosphate (LiPF ₆ ), lithium borofluoride (LiBF ₄ ), lithium hexafluoroarsenate (LiAsF ₆ ), trifluoro - lithium salts such as lithium metasulfonate (LiCF ₃ SO ₃ ), and lithium bis-trifluoromethylsulfonylimide [LiN(CF ₃ SO ₂ ) ₂ ]. Among them, LiPF ₆ , LiBF ₄ and LiN(CF ₃ SO ₂ ) ₂ are preferred. The content of the electrolyte salt in the nonaqueous solvent is preferably 0.5 to 2.0 mol/l.

For sodium cells, electrolytes (including non-flammable semi-solid electrolytes) are sodium perchlorate ( _NaClO4 ), sodium hexafluorophosphate ( _NaPF6 ), sodium borofluoride ( _NaBF4 ), sodium hexafluoroarsenide, tri- containing sodium salts preferably selected from sodium fluoro-methasulfonate (NaCF ₃ SO ₃ ), sodium bis-trifluoromethylsulfonylimide (NaN(CF ₃ SO ₂ ) ₂ ), ionic liquid salts, or combinations thereof Sometimes.

Ionic liquids are composed only of ions. Ionic liquids are salts with low melting temperatures that become molten or liquid when a desired temperature is exceeded. For example, a salt is considered an ionic liquid if its melting point is below 100°C. If the melting temperature is below room temperature (25° C.), the salt is called a room temperature ionic liquid (RTIL). IL salts are characterized by weak interactions in combination with large cations and charge-delocalized anions. This reduces the tendency to crystallize due to flexibility (anions) and asymmetry (cations).

A typical well-known ionic liquid is formed by combining the 1-ethyl-3-methylimidazolium (EMI) cation with the N,N-bis(trifluoromethane)sulfonamide (TFSI) anion. This combination results in a fluid with ionic conductivity comparable to many organic electrolyte solutions up to about 300-400° C., as well as low degradability and low vapor pressure. This suggests electrolytes that are generally less volatile and non-flammable and thus much safer for batteries.

Ionic liquids are basically composed of organic ions that undergo an essentially unlimited number of structural changes due to the ease of preparing a wide variety of components. Therefore, different types of salts can be used to design ionic liquids with desired properties for a given application. These include, inter alia, imidazolium, pyrrolidinium and quaternary ammonium salts as cations and bis(trifluoromethanesulfonyl)imide, bis(fluorosulfonyl)imide and hexafluorophosphate as anions. Based on their composition, ionic liquids basically fall into different classes, including aprotic, protic and zwitterionic forms, each suitable for specific applications.

Common cations of room temperature ionic liquids (RTILs) include, but are not limited to, tetraalkylammonium, di-, tri-, and tetra-alkylimidazolium, alkylpyridinium, dialkylpyrrolidinium, dialkylpiperidinium, tetra Alkylphosphonium, as well as trialkylsulfonium are mentioned. Common anions of RTIL include, but are not limited to, BF ₄ ⁻ , B(CN) ₄ ⁻ , CH ₃ BF ₃ ⁻ , CH2CHBF ₃ ⁻ , CF ₃ BF ₃ ⁻ , C ₂ F ₅ BF ₃ ⁻ , n _-C3F7BF3- ^, _{n - C4F9BF3- , PF6-} ^, _{CF3CO2- , CF3SO3-} ^, N _{( SO2CF3} ^{) 2- ,} _{N ( COCF3 )} (SO ₂ CF ₃ ) ⁻ , N(SO ₂ F) ₂ ⁻ , N(CN) ₂ ⁻ , C(CN) ₃ ⁻ , SCN ⁻ , SeCN ⁻ , CuCl ₂ ⁻ , AlCl ₄ ⁻ , F(HF) _{2 .3} ^- and the like. Relatively speaking, imidazolium or sulfonium based cations and AlCl ₄ ⁻ , BF ₄ ⁻ , CF ₃ CO ₂ ⁻ , CF ₃ SO ₃ ⁻ , NTf ₂ ⁻ , N(SO ₂ F) ₂ ⁻ , or F Combinations with complex halide anions such as (HF) _2.3 ^- lead to RTILs with good operational conductivity.

RTILs have high intrinsic ionic conductivity, high thermal stability, low volatility, low (substantially zero) vapor pressure, non-flammability, and the ability to remain liquid over a wide temperature range above and below room temperature. , high polarity, high viscosity, and a wide electrochemical window. These properties, with the exception of high viscosity, are desirable properties when using RTILs as electrolyte components (salts and/or solvents) in supercapacitors.

In the following, several different types of anode active materials, cathode active materials, and porous current collector materials (e.g., graphite foam, graphene foam, and metal foams) are provided. These illustrative examples, as well as the rest of the specification and drawings, individually or in combination, are more than sufficient to enable those skilled in the art to practice the invention. However, these examples should not be construed as limiting the scope of the invention.

Example 1: Preparation of Graphene Oxide (GO) and Reduced Graphene Oxide (RGO) Nanosheets from Natural Graphite Powder Huadong Graphite Co.; (Qingdao, China) was used as the starting material. GO was obtained by following the well-known modified Hummers method. This method involved two oxidation stages. In a typical procedure, the first oxidation was achieved under the following conditions. 1100 mg of graphite was placed in a 1000 mL boiling flask. Then K ₂ S ₂ O ₈ , 20 g of P ₂ O ₅ and 400 mL of concentrated H ₂ SO ₄ aqueous solution (96%) were added to the flask. The mixture was heated under reflux for 6 hours and then left at room temperature for 20 hours. The graphite oxide was filtered and rinsed with copious amounts of distilled water to neutral pH. At the end of this first oxidation, a wet cake material was recovered.

_In the second oxidation process, the previously collected wet cake was placed in a boiling flask containing 69 mL of concentrated aqueous H2SO4 ₍ 96%). The flask was kept in an ice bath while 9 g of KMnO ₄ was added slowly. Care was taken to avoid overheating. The resulting mixture was stirred at 35° C. for 2 hours (sample color turned dark green) followed by the addition of 140 mL of water. After 15 minutes, the reaction was quenched by adding 420 mL of water and 15 mL of 30 wt % H ₂ O ₂ aqueous solution. The color of the sample at this stage turned bright yellow. The mixture was filtered and rinsed with 1:10 aqueous HCl to remove metal ions. Collected material was gently centrifuged at 2700 g and rinsed with deionized water. The final product was a wet cake containing 1.4 wt% GO as estimated from the dry extract. A liquid dispersion of GO platelets was then obtained by lightly sonicating the wet cake material diluted with deionized water.

Surfactant-stabilized RGO (RGO-BS) was obtained by diluting the wet cake with an aqueous surfactant solution instead of pure water. A commercial mixture of salts of sodium cholate (50 wt%) and sodium deoxycholate (50 wt%) provided by Sigma Aldrich was used. The weight fraction of surfactant was 0.5 wt%. This fraction was kept constant for all samples. Sonication was performed using a Branson Sonifier S-250A equipped with a 13 mm step distractor horn and a 3 mm tapered microtip operating at a frequency of 20 kHz. For example, 10 mL of an aqueous solution containing 0.1 wt % GO was sonicated for 10 minutes and then centrifuged at 2700 g for 30 minutes to remove undissolved large particles, aggregates, and impurities. Chemical reduction of GO obtained as described above was carried out to produce RGO by following a method comprising placing 10 mL of 0.1 wt % GO aqueous solution in a 50 mL boiling flask. Then, 10 μL of 35 wt % N ₂ H ₄ (hydrazine) aqueous solution and 70 mL of 28 wt % NH ₄ OH (ammonia) aqueous solution were added to the surfactant-stabilized mixture. The solution was heated to 90° C. and refluxed for 1 hour. The pH value measured after the reaction was about 9. The color of the sample turned dark black during the reduction reaction.

Some lithium batteries according to the present invention have used RGO as a conductive additive in either or both of the anode and cathode active materials. Prelithiated RGO (eg, RGO + lithium particles or RGO pre-deposited with a lithium coating) was also used as the anode active material in selected lithium-ion cells.

For comparison, a slurry coating and drying procedure was performed to produce a conventional electrode. One anode and one cathode and a separator disposed between the two electrodes are then assembled into an Al-plastic laminated packaging envelope followed by injection of a liquid electrolyte to produce a conventional lithium A battery cell was formed.

Example 2 Preparation of Sheets of Pure Graphene (0% Oxygen) Recognizing the possibility that high defect populations in GO sheets act to reduce the electrical conductivity of individual graphene planes, we , by using sheets of pure graphene (e.g., non-oxidized, oxygen-free, non-halogenated, halogen-free) conductive additives with high electrical and thermal conductivity I decided to research if I could get the drug. Prelithiated pure graphene was also used as the anode active material. Sheets of pure graphene were fabricated by using direct sonication or liquid phase fabrication methods.

In a typical procedure, 5 grams of graphite flakes ground to a size of about 20 μm or less were mixed with 1,000 mL of deionized water (containing 0.1% by weight of dispersant, Zonyl® FSO from DuPont). to obtain a suspension. An ultrasonic energy level of 85 W (Branson S450 Ultrasonicator) was used for exfoliation, separation, and size reduction of graphene sheets over a period of 15 minutes to 2 hours. The resulting graphene sheets are pure graphene that has never been oxidized, does not contain oxygen, and is relatively defect-free. Pure graphene is essentially free of non-carbon elements.

Sheets of pure graphene were then used as a conductive additive for anode activity using both a slurry injection procedure into the foam pores according to the present invention and a conventional slurry coating, drying and lamination procedure. The material (or cathode active material in the case of the cathode) was incorporated into the cell. Both lithium-ion and lithium-metal batteries (cathode-only injection) were investigated.

Example 3 Preparation of Prelithiated Graphene Fluoride Sheets as Anode Active Materials for Lithium-Ion Batteries Several methods were used to produce GFs, but only one method is described here as an example. In a typical procedure, heavily exfoliated graphite ( _HEG ) was prepared from the intercalate compound _C2F.xClF3 . HEG was further fluorinated by chlorine trifluoride vapor to produce fluorinated heavily exfoliated graphite (FHEG). A pre-chilled Teflon reactor was charged with 20-30 mL of pre-chilled liquid ClF ₃ , the reactor was closed and cooled to liquid nitrogen temperature. 1 g or less of HEG was then placed in a container with holes that allowed ClF ₃ gas to enter the interior of the reactor. In 7-10 days, a grey-beige product with the approximate formula C ₂ F was formed.

A small amount of FHEG (approximately 0.5 mg) was then mixed with 20-30 mL of organic solvent (methanol and ethanol separately) and sonicated (280 W) for 30 minutes to produce a homogeneous yellowish dispersion. did. After removal of solvent, the dispersion became a brownish powder. Graphene fluoride powder was mixed with surface-stabilized lithium powder in a liquid electrolyte to cause prelithiation.

Example 4 Some Examples of Electrolytes Used Preferred sodium metal salts include: sodium perchlorate (NaClO ₄ ), sodium hexafluorophosphate (NaPF ₆ ), sodium borofluoride (NaBF ₄ ), sodium hexafluoroarsenide, potassium hexafluoroarsenide, sodium trifluoro-methasulfonate (NaCF ₃ SO ₃ ), and sodium bis-trifluoromethylsulfonylimide (NaN(CF ₃ SO ₂ ) ₂ ). The following are good choices for lithium salts that tend to be well soluble in the organic or ionic liquid solvent of choice. lithium borofluoride (LiBF ₄ ), lithium trifluoro-methasulfonate (LiCF ₃ SO ₃ ), lithium bis-trifluoromethylsulfonylimide (LiN(CF ₃ SO ₂ ) ₂ or LITFSI), lithium bis(oxalato)borate ( LiBOB), lithium oxalyldifluoroborate ( _LiBF2C2O4 ), and lithium _{bisperfluoroethylsulfonylimide} ( _LiBETI ). A good electrolyte additive that helps stabilize Li metal is _LiNO3 . A particularly useful ionic liquid-based lithium salt includes lithium bis(trifluoromethanesulfonyl)imide (LiTFSI).

Preferred organic liquid solvents include the following. ethylene carbonate (EC), dimethyl carbonate (DMC), methyl ethyl carbonate (MEC), diethyl carbonate (DEC), propylene carbonate (PC), acetonitrile (AN), vinylene carbonate (VC), allyl ethyl carbonate (AEC), 1,3-dioxolane (DOL), 1,2-dimethoxyethane (DME), tetraethylene glycol dimethyl ether (TEGDME), poly(ethylene glycol) dimethyl ether (PEGDME), diethylene glycol dibutyl ether (DEGDBE), 2-ethoxyethyl ether ( EEE), hydrofluoroethers (eg TPTP), sulfones, and sulfolane.

Preferred ionic liquid solvents may be selected from room temperature ionic liquids (RTIL) with cations selected from tetraalkylammonium, di-alkylimidazolium, alkylpyridinium, dialkyl-pyrrolidinium, or dialkylpiperidinium. The counter anions are preferably BF ₄ ⁻ , B(CN) ₄ ⁻ , CF ₃ CO ₂ ⁻ , CF ₃ SO ₃ ⁻ , N(SO ₂ CF ₃ ) ₂ ⁻ , N(COCF ₃ )(SO ₂ CF ₃ ) ⁻ , or N(SO ₂ F) ₂ ⁻ . Particularly useful ionic liquid-based solvents include the following. Nn-butyl-N-ethylpyrrolidinium bis(trifluoromethanesulfonyl)imide (BEPyTFSI), N-methyl-N-propylpiperidinium bis(trifluoromethylsulfonyl)imide (PP ₁₃ TFSI), and N, N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethylsulfonyl)imide.

Example 5: Vapor Pressures of Several Solvents and Corresponding Semisolid Electrolytes with Various Sodium Salt Molecular Ratios Sodium Borofluoride ( _NaBF4 ), Sodium Perchlorate ( _NaClO4 ), or Bis(trifluoromethanesulfonyl) of several solvents (DOL, DME, PC, AN, with or without the ionic liquid-based co-solvent PP ₁₃ TFSI) before and after addition of sodium salts over a wide molecular ratio range, such as sodium imide (NaTFSI). Vapor pressure was measured. As shown in FIGS. 2A-2D, some of the vapor pressure ratio data (p _s /p=vapor pressure of solution/vapor pressure of solvent alone) were plotted along with curves representing Raoult's law. Plot as a function of salt molar ratio x. In all cases, the vapor pressure ratio follows the theoretical prediction based on Raoult's law only up to x<0.15. Beyond this, the vapor pressure deviates from Raoult's law with new and unprecedented behavior. The vapor pressure appears to drop very rapidly when the molecular ratio x exceeds 0.2 and rapidly approach a minimum or essentially zero when x exceeds 0.4. If the p _s /p value is too low, the vapor phase of the electrolyte cannot initiate a flame or sustain a flame for longer than 3 seconds after initiation.

Example 6: Flash Points and Vapor Pressures of Several Solvents and Corresponding Semi-Solid Electrolytes with a Sodium or Lithium Salt Molecular Ratio of x=0.3 The flash points and vapor pressures of these solvents and their electrolytes are shown in Table 1 below. Note that liquids with flash points below 38.7° C. are flammable according to the OSHA (Occupational Safety and Health Administration) classification. However, to ensure safety, we designed the quasi-solid electrolyte to exhibit a flash point significantly higher than 38.7°C (e.g., at least 50°C, preferably 150° C.). The data in Table 1 show that addition of alkali metal salt to a molar ratio of 0.35 is generally sufficient to meet these criteria. All of our semi-solid electrolytes are non-flammable.

Example 7 Alkali Metal Ion Transference Numbers in Several Electrolytes The Na ⁺ ion transference numbers of several types of electrolytes (eg, NaTFSI salt/(EMImTFSI+DME) solvent) related to the molar ratio of lithium salts were studied. Representative results are summarized in FIGS. 3(A)-3(D). In general, the Na ⁺ ion transference number in low salt concentration electrolytes decreases as the concentration increases from x=0 to x=0.2-0.35. However, beyond a molecular ratio of x=0.2-0.35, the transference number increases with increasing salt concentration, indicating a fundamental change in the Na ⁺ ion transport mechanism. This was explained earlier in the theoretical subsection. When a Na ⁺ ion moves in a low salt concentration electrolyte (eg, x<0.2), it can ^entrain multiple solvate molecules with it. Coordinated movement of such clusters of charged species can be further impeded if the fluid viscosity is increased by more salt dissolved in the solvent. In contrast, when very high concentrations of sodium salts (eg, x>0.2) are present, Na ⁺ ions can greatly outnumber the available solvate molecules. Such solvating molecules can otherwise cluster sodium ions, forming multi-ionic complex species and slowing the diffusion process of Na ⁺ ions. This high Na ⁺ ion concentration makes it possible to have more “free Na ⁺ ions” (unclustered), which gives a high Na ⁺ transference number (hence, facile Na ⁺ transport) . The sodium ion transport mechanism shifts from a multi-ion complex-dominated mechanism (with a larger overall hydrodynamic radius) to a single ion-dominated mechanism with a large number of available free Na ⁺ ions (with a smaller hydrodynamic radius). have). This observation further suggests that a suitable number of Na ⁺ ions can rapidly migrate through or out of the semi-solid electrolyte to facilitate interaction or reaction with the cathode (during discharging) or the anode (during charging). to ensure good rate capability of sodium secondary cells. Most importantly, these highly concentrated electrolytes are non-flammable and safe. Therefore, it is very difficult to obtain a combination of safety, facile sodium ion transport and electrochemical performance characteristics for all types of sodium and lithium secondary batteries.

Example 8 Lithium Iron Phosphate (LFP) Cathodes for Lithium Metal Batteries Uncoated or carbon-coated LFP powders are commercially available from several sources. In this example, an electrode containing LFP particles as the cathode active material and an electrolyte (containing a lithium salt dissolved in an organic solvent) was coated with graphene sheets (RGO) and carbon nanofibers (CNF) as conductive filaments. separately included. The lithium salts used in this example included lithium borofluoride ( _LiBF4 ) and the organic solvents were PC, DOL, DEC, and mixtures thereof. This study included a wide range of conductive filament volume fractions from 0.1% to 30%. Formation of the electrode layer was accomplished using the following sequence of steps.

Sequence 1 (S1): First, _LiBF4 salt was dissolved in a mixture of PC and DOL to form electrolytes with salt concentrations of 1.0 M, 2.5 M, and 3.5 M, respectively (2.5 M and above). , the resulting electrolyte was no longer a liquid electrolyte, in fact behaved more like a solid, hence the use of the term "quasi-solid"). RGO or CNT filaments were then dispersed in the electrolyte to form a filament-electrolyte suspension. Mechanical shear was used to help create a uniform dispersion (this filament-electrolyte suspension was fairly viscous even at salt concentrations as low as 1.0 M). The cathode active material, LFP particles, were then dispersed in the filament-electrolyte suspension to form a semi-solid electrode material.

Sequence 2 (S2): First, _LiBF4 salt was dissolved in a mixture of PC and DOL to form electrolytes with salt concentrations of 1.0 M, 2.5 M, and 3.5 M, respectively. The cathode active material LFP particles were then dispersed in the electrolyte to form an active particle-electrolyte suspension. Mechanical shear was used to help create a uniform dispersion (this active particle-electrolyte suspension was fairly viscous even at salt concentrations as low as 1.0 M). The RGO or CNT filaments were then dispersed in the active particle-electrolyte suspension to form a quasi-solid electrode material.

Sequence 3 (S3): First, the desired amount of RGO or CNT filaments were dispersed in a liquid solvent mixture (PC+DOL) containing no dissolved lithium salt. Mechanical shear was used to help form a uniform suspension of the conducting filaments in the solvent. LiBF ₄ salt and LFP particles were then added to the suspension, and the LiBF ₄ salt was dissolved in the suspension's solvent mixture to have salt concentrations of 1.0 M, 2.5 M, and 3.5 M, respectively. An electrolyte was formed. Simultaneously or subsequently, the LFP particles were dispersed in the electrolyte to form a deformable quasi-solid electrode material. This quasi-solid electrode material consists of active material particles and conductive filaments dispersed in a quasi-solid electrolyte (not a liquid electrolyte). In this quasi-solid electrode material, the conducting filaments percolate to form a 3D network of electron conducting pathways. This 3D conducting network is maintained when the electrode material is molded into the battery's electrodes.

Electrode conductivity was measured using a four-point probe method. The results are summarized in Figures 6(A) and 6(B). As these data show, typically the percolation of conductive filaments (CNF or RGO) to form a 3D network of electronically conductive pathways is conductive It does not occur until the volume fraction of filaments exceeds 10-12%. In other words, the step of dispersing the conductive filaments in the liquid solvent should be performed before the lithium salt or sodium salt is dissolved in the liquid solvent and before the active material particles are dispersed in the solvent. Such a sequence also allows percolation thresholds to be as low as 0.5% to 2.0%, with minimal amounts of conductive additive and thus a higher proportion of active material (and higher energy density). makes it possible to manufacture conductive electrodes by using It was also found that these observations apply to all types of electrodes investigated so far, including active material particles, conductive filaments, and electrolytes. This is a very important and unexpected process requirement for preparing high performance alkali metal batteries with both high energy density and high power density.

A quasi-solid cathode, a porous separator, and a quasi-solid anode (prepared in a similar manner but with artificial graphite particles as the anode active material) are then assembled together to form a unit cell, which is then was housed in a protective housing (laminated aluminum plastic pouch) with two protruding terminals to form a battery. Batteries containing liquid electrolyte (1M) and semi-solid electrolytes (2.5M and 3.5M) were fabricated and tested.

For comparison, a slurry coating and drying procedure was performed to produce a conventional electrode. Then, one anode and one cathode and a separator disposed between the two electrodes are assembled and housed in an Al plastic laminate packaging container, followed by injection of liquid electrolyte to achieve prior art A lithium battery was formed. The battery test results are summarized in Example 19.

Example ₉ : _V2O5 as an example of a transition metal oxide cathode active material for lithium batteries
V ₂ O ₅ powder is commercially available separately. In a typical experiment, for the preparation of graphene-supported V ₂ O ₅ powder samples, vanadium pentoxide gels were obtained by mixing V ₂ O ₅ into LiCl aqueous solutions. The Li ⁺ exchanged gel obtained by interaction with a LiCl solution (li:V molar ratio was kept at 1:1) was mixed with the GO suspension and then placed in a Teflon-lined stainless steel 35 ml autoclave. Sealed and heated to 180° C. for 12 hours. After such hydrothermal treatment, the raw solids were collected, washed thoroughly, sonicated for 2 minutes, dried at 70° C. for 12 hours, then mixed with additional 0.1% GO in water, The nanobelt size was crushed by sonication and then spray-dried at 200° C. to obtain graphene-encapsulated composite particles.

V ₂ O ₅ powder (conductive additive ) and the graphene-supported V ₂ O ₅ powder were separately incorporated into the battery together with the liquid electrolyte.

Example ₁₀ : LiCoO2 as an example of a lithium transition metal oxide cathode active material for lithium ion batteries
Commercially available LiCoO ₂ powder and multi-walled carbon nanotubes (MW-CNTs) were dispersed in a liquid electrolyte to form a quasi-solid electrode. Two types of quasi-solid anodes were prepared for coupling with the cathode. One contains graphite particles as anode active material and the other contains graphene-encapsulated Si nanoparticles as anode active material. The electrolyte used was EC-VC (80/20 ratio). Each cell contains a quasi-solid anode, a separator layer, and a quasi-solid cathode assembled together and then hermetically sealed.

LiCoO2 powder, carbon black powder, and PVDF resin binder _were separately dispersed in NMP solvent to form a slurry, which was applied to both sides of the Al foil current collector, and then vacuum dried to form the cathode layer. formed. Graphite particles and a PVDF resin binder were dispersed in an NMP solvent to form a slurry, which was coated on both sides of a Cu foil current collector and then vacuum dried to form an anode layer. The anode layer, separator and cathode layers were then laminated and encased in an Al-plastic housing into which a liquid electrolyte was injected to form a conventional lithium ion battery.

カソード活性材料（Ｌｉ_２Ｃ_６Ｏ_６）と導電性添加剤（カーボンブラック、１５％）との混合物を１０分間ボールミル加工し、得られたブレンドを研磨して複合物粒子を製造した。電解質は、ＰＣ－ＥＣ中で１Ｍのヘキサフルオロリン酸リチウム（ＬｉＰＦ_６）であった。 Example ₁₁ : Organic Material ( _Li2C6O6 ) as _Cathode Active Material in Lithium Metal Batteries
To synthesize dilithium rhodizonate (Li ₂ C ₆ O ₆ ), rhodizonate dihydrate (species 1 in the formula below) was used as a precursor. A basic lithium salt Li ₂ CO ₃ can be used in aqueous media to neutralize both enediolic acid functions. Strict stoichiometric amounts of both reactants, rhodizonic acid and lithium carbonate, were reacted for 10 hours to achieve a yield of 90%. Dilithium rhodizonate (species 2) is readily soluble in even small amounts of water, suggesting that water molecules are present in species 2. Water was removed in vacuo at 180° C. for 3 hours to give the anhydrous form (species 3).

A mixture of cathode active material (Li ₂ C ₆ O ₆ ) and conductive additive (carbon black, 15%) was ball milled for 10 minutes and the resulting blend was ground to produce composite particles. The electrolyte was 1 M lithium hexafluorophosphate (LiPF ₆ ) in PC-EC.

Note that the two Li atoms in the formula Li ₂ C ₆ O ₆ are part of a fixed structure and do not participate in the reversible storage and release of lithium ions. This suggests that lithium ions must come from the anode side. Therefore, a lithium source (eg, lithium metal or lithium metal alloy) must be present at the anode. A layer of lithium is deposited on the anode current collector (Cu foil) (eg, by sputtering or electrochemical plating, or by using lithium foil), as shown in FIG. 1(D). Following this, the lithium coating layer, porous separator, and quasi-solid cathode were assembled into the cell. Cathode active material and conductive additive (Li ₂ C ₆ O ₆ /C composite particles) were dispersed in the liquid electrolyte. For comparison, a corresponding conventional Li metal cell was also fabricated by conventional procedures of slurry coating, drying, lamination, packaging, and electrolyte injection.

Example 12 Metal Naphthalocyanine-RGO Hybrid Cathodes for Lithium Metal Batteries Copper Naphthalocyanine (CuPc) by Vaporizing CuPc in a Chamber with Graphene Films (5 nm) Prepared from Spin-Coating of RGO-Water Suspension A coated graphene sheet was obtained. The resulting coated film was cut and ground to produce CuPc-coated graphene sheets, which had lithium metal foil as the anode active material, and 1.0 M and It was used as a cathode active material in a lithium metal battery with 3.0M _LiClO4 .

Example 13 Preparation of MoS2/RGO Hybrid Materials as Cathode Active Materials for Lithium Metal Batteries _In this example, a variety of inorganic materials were investigated. For example, the one-step solvothermal reaction of (NH ) ₂ MoS ₄ and hydrazine in N,N-dimethylformamide (DMF) solution of oxidized graphene oxide (GO) at 200 °C _yields ultrathin MoS ₂ /RGO hybrids were synthesized. In a typical procedure, 22 mg (NH ₄ ) ₂ MoS ₄ was added to 10 mg DMF dispersed in 10 ml DMF. The mixture was sonicated at room temperature for about 10 minutes until a clear, homogeneous solution was obtained. Then _{0.1 ml} of _N2H4.H2O was added. The reaction solution was sonicated for an additional 30 minutes before being transferred to a Teflon-lined 40 mL autoclave. The system was heated at 200° C. for 10 hours in an oven. The product was collected by centrifugation at 8000 rpm for 5 minutes, washed with DI water and recollected by centrifugation. The washing step was repeated at least 5 times to ensure most of the DMF was removed. Finally, the product was dried into a cathode. Finally, the dried product was mixed with some carbon fibers and a semi-solid electrolyte to form a deformable semi-solid cathode.

Example 14 Preparation of Two-Dimensional (2D) Layered Bi ₂ Se ₃ Chalcogenide Nanoribbons The preparation of (2D) layered Bi ₂ Se ₃ chalcogenide nanoribbons is well known in the art. For example, a vapor-liquid-solid (VLS) method was used to grow Bi ₂ Se ₃ nanoribbons. The nanoribbons produced herein are on average 30-55 nm thick and range in width and length from hundreds of nanometers to several micrometers. Nanoribbons prepared by these procedures and either graphene sheets or exfoliated graphite flakes were combined with semi-solid electrolytes to form deformable cathodes for lithium metal batteries.

Example 15: MXene powder + chemically activated RGO
Selected MXenes were produced by partially etching away specific elements from layered structures of metal carbides such as Ti ₃ AlC ₂ . For example, 1 M NH ₄ HF ₂ aqueous solution was used at room temperature as an etchant for Ti ₃ AlC ₂ . Typically, MXene surfaces are terminated with O, OH, and/or F groups. This is why they are usually called _{Mn+ 1XnTx} , where M is an early transition metal, X is C and/or _N , and T is a terminal group (O, OH, and/or F), where n=1, 2, or 3 and x is the number of end groups. _{MXene materials investigated include Ti2CTx} , _{Nb2CTx , V2CTx , Ti3CNTx} , and _Ta4C3Tx . Typically, 35-95% MXene sheets and 2-35% graphene sheets were mixed in a semi-solid electrolyte to form a semi-solid cathode.

Example 16: Preparation of graphene-supported _MnO2 cathode active materials MnO2 powders were synthesized by _two methods (with or without graphene sheets, respectively). In one method, a 0.1 mol/L KMnO ₄ aqueous solution was prepared by dissolving potassium permanganate in deionized water. Meanwhile, 13.32 g of high purity sodium bis(2-ethylhexyl) sulfosuccinate surfactant was added to 300 mL of isooctane (oil) and stirred well to obtain an optically clear solution. Then, 32.4 mL of 0.1 mol/L KMnO ₄ solution and selected amount of GO solution were added into the solution, which was sonicated for 30 min to prepare a dark brown precipitate. . The product was isolated, washed several times with distilled water and ethanol, and dried at 80° C. for 12 hours. The sample was powdered _MnO2 supported on graphene, which was dispersed in a CNT-containing electrolyte to form a semi-solid cathode electrode.

Example 17: Graphene Reinforced Nanosilicon as Anode Active Material for Lithium-Ion Batteries Graphene-encapsulated Si particles were manufactured by Angstron Energy Co.; (Dayton, Ohio, USA). Pure graphene sheets (as conductive filaments) were dispersed in a PC-DOL (50/50 ratio) mixture, followed by graphene-covered Si particles (anode active material) and mixed at 60°C. A semi-solid anode electrode was prepared by dissolving 2.5 M lithium hexafluorophosphate (LiPF ₆ ) in a solvent. The DOL was then removed to obtain a semi-solid electrolyte containing about 5.0 M _LiPF6 in PC. This leads to supersaturation of _LiPF6 as the maximum solubility of _LiPF6 in PC is known to be less than 3.0 M at room temperature.

Example 18 Cobalt Oxide ₍ Co3O4) Fine Particles as Anode Active Material LiCoO2 is the cathode active material of lithium _- ion _{batteries ,} while _Co3O4 is the anode active material. Because LiCoO ₂ has an electrochemical potential of about +4.0 volts vs. Li/Li ⁺ and Co ₃ O ₄ has an electrochemical potential of about +0.8 volts vs. Li/Li ⁺ . is.

Appropriate amount of inorganic salt Co(NO ₃ ) _{2.6H 2 O followed by ammonia solution (NH 3.H 2 O , 25} wt %) was slowly added to the GO suspension. The resulting precursor suspension was stirred under a stream of argon for several hours to ensure complete reaction. The resulting Co(OH) ₂ /graphene precursor suspension was divided into two portions. One portion was filtered and vacuum dried at 70° C. to obtain a Co(OH) ₂ /graphene composite precursor. The precursor was calcined in air at 450° C. for 2 hours to form a layered Co ₃ O ₄ /graphene composite. It is characterized by having Co ₃ O ₄ -coated graphene sheets on top of each other.

Example 19: Graphene Reinforced Tin Oxide Microparticles as Anode Active Materials Tin oxide ₍ SnO2) nanoparticles _were obtained by controlled hydrolysis of _SnCl4.5H2O and NaOH using the following procedure: SnCl ₄ .5H ₂ O (0.95 g, 2.7 m-mol) and NaOH (0.212 g, 5.3 m-mol) were each dissolved in 50 mL of distilled water. The NaOH solution was added dropwise at a rate of 1 mL/min to the tin chloride solution with vigorous stirring. The solution was homogenized by sonication for 5 minutes. The resulting hydrosol was then reacted with the GO dispersion for 3 hours. A few drops of 0.1 M H ₂ SO ₄ were added to the mixed solution to aggregate the product. The precipitated solid was collected by centrifugation, washed with water and ethanol and dried in vacuum. The dried product was heat treated at 400° C. for 2 hours under Ar atmosphere and used as an anode active material.

Example 20 Preparation and Electrochemical Testing of Various Battery Cells For most of the anode and cathode active materials investigated, lithium ion or lithium metal cells were prepared using both the method according to the invention and conventional methods. prepared.

In conventional methods, a typical anode composition consists of 85 wt % active material (eg, Si or Co ₃ O ₄ coated graphene sheets) dissolved in N-methyl-2-pyrrolidinone (NMP) and 7 wt % acetylene black (Super-P) and 8 wt % polyvinylidene fluoride binder (PVDF, 5 wt % solids). After coating the slurry on the Cu foil, the electrode was vacuum dried at 120° C. for 2 hours to remove the solvent. By this method, typically no binder resin is required or used, saving 8% by weight (reducing the amount of non-active materials). The cathode layer is similarly formed (using Al foil as the cathode current collector) using conventional slurry coating and drying procedures. The anode layer, separator layer (eg Celgard 2400 membrane), and cathode layer are then laminated together and encased within a plastic Al envelope. As an example, a 2.8 M LiPF ₆ electrolyte solution dissolved in a mixture of ethylene carbonate (EC) and diethyl carbonate (DEC) (EC-DEC, 1:1 v/v) is injected into the cell. Some cells used ionic liquids as liquid electrolytes. A cell assembly was formed in an argon-filled glove box.

The process according to the invention preferably incorporates a semi-solid anode, a porous separator, and a semi-solid cathode within a protective housing. The pouch was then sealed.

Cyclic voltammetry (CV) measurements were performed using an Arbin electrochemical workstation with a typical scan rate of 1 mV/s. Furthermore, the electrochemical performance of various cells was evaluated at current densities from 50 mA/g to 10 A/g by galvanostatic charge/discharge cycles. A LAND multi-channel battery tester was used for long-term cycling tests.

In the lithium-ion battery industry, it is common practice to define the cycle life of a battery as the number of charge-discharge cycles at which the battery undergoes a 20% capacity fade based on the initial capacity measured after the required electrochemical formation. be.

Example 21: Typical Test Results For each sample, several current densities (representing charge/discharge rates) were imposed to determine the electrochemical response and the Ragone plot (power density versus energy density) It enabled the calculation of the energy density and power density values required for construction. FIG. 7 shows a Ragone plot (weight power density versus energy density) of a lithium-ion battery cell containing graphite particles as the anode active material and carbon-coated LFP particles as the cathode active material. Three of the four data curves are for cells prepared according to embodiments of the invention (using the orders S1, S2, and S3, respectively), and the remaining one is for conventional slurry coating of electrodes. (roll coating). Several important observations can be made from these data.

The gravimetric energy densities and power densities of lithium-ion battery cells prepared by the method according to the invention are significantly higher than those of their counterparts prepared by conventional roll-coating methods (denoted "conventional"). A change from an anode thickness of 160 μm (coated on a flat solid Cu foil) to a thickness of 315 μm and a corresponding change in the cathode to maintain a balanced capacity ratio resulted in An increase in gravimetric energy density to 230 Wh/kg (S1), 235 Wh/kg (S2), and 264 Wh/kg (S3) occurred. Also, surprisingly, batteries containing quasi-solid electrodes according to the present invention with a 3D network of electronic conduction paths (due to percolation of conductive filaments) provide significantly higher energy densities and higher power densities.

These large differences are not solely due to increased electrode thickness and mass loading. This difference is probably due to the following. Significantly higher active material mass loading (rather than just mass loading) and higher electrical conductivity associated with cells according to the present invention; reduced ratio of overhead (inactive) components to weight/volume of active material; Moderate utilization (high conductivity allows most, if not all, graphite particles and LFP particles to contribute to lithium-ion storage capacity, leaving no dry pockets or ineffectiveness in the electrode, especially under high charge/discharge rate conditions). no specific spots).

FIG. 8 shows Ragone plots (gravimetric energy density versus gravimetric power density) of two cells containing graphene-encapsulated Si nanoparticles as anode active material and LiCoO ₂ nanoparticles as cathode active material. Experimental data were obtained from Li-ion battery cells prepared by the method according to the present invention and Li-ion battery cells prepared by conventional slurry coating of electrodes.

These data show that the gravimetric energy density and power density of battery cells prepared by the method according to the invention are significantly higher than their counterparts prepared by conventional methods. The difference is big here too. Cells formed in a conventional manner exhibit a gravimetric energy density of 265 Wh/kg, while cells according to the invention deliver energy densities of 393 Wh/kg (S1) and 421 Wh/kg (S3) respectively. The high power densities of 1425 W/kg and 1,654 W/kg are also unprecedented for lithium-ion batteries.

The difference in these energy densities and power densities is mainly due to the following. High active material mass loading (>25 mg/cm ² for anode and >45 mg/cm ² for cathode) and high electrical conductivity associated with cells according to the invention; ratio of overhead (non-active) components to active material weight/volume and a better utilization of the active material particles (all particles accessible to the liquid electrolyte, fast ionic and electronic motion), a feature of the method according to the invention.

FIG. 9 shows lithium foil as an anode active material, dilithium rhodizonate (Li ₂ C ₆ O ₆ ) as a cathode active material, and lithium salt (LiPF ₆ )-PC/DEC (1. Ragone plots of lithium metal batteries containing both 5M and 5.0M are shown. The quasi-solid electrodes were prepared according to the sequences S2 and S3 described in Example 8. The data relate both to three lithium metal cells prepared by the method according to the invention and to a lithium metal cell prepared by conventional slurry coating of electrodes.

These data show that the gravimetric energy density and power density of lithium metal cells prepared by the method according to the invention are significantly higher than their counterparts prepared by conventional methods. Again, the difference is very large, and this is due to the much higher active material mass loading (rather than just mass loading) associated with the electrodes of the invention and the higher electrical conductivity, overhead on active material weight/volume (non-active ) component ratio, and the surprisingly good utilization of the electrode active material (higher conductivity and no dry pockets or no Lack of effective spots contributes to the lithium ion storage capacity of most, if not all, active materials).

The gravimetric energy density of the lithium metal-organic cathode cell according to the present invention is as high as 515 Wh/kg, which is the gravimetric energy density of all rechargeable lithium metal or lithium ion batteries reported so far (current lithium ion batteries have a total cell The observation of higher than 150-220 Wh/kg based on weight) is quite remarkable and surprising. Furthermore, a weight power density of 1,576 W/kg was unthinkable for organic cathode active material-based lithium batteries. Cells containing quasi-solid electrodes prepared according to Sequence 3 exhibit significantly higher energy and power densities compared to conventional Sequence S2 cells. Also, surprisingly, a higher concentration of electrolyte (quasi-solid electrolyte) contributes to achieving higher energy and power densities.

The above performance characteristics of lithium batteries are also observed in corresponding sodium batteries. Due to space limitations, data for sodium batteries are not presented here. However, as an example, FIG. 10 shows a Ragone plot of two sodium ion capacitors each containing pre-sodiumized hard carbon particles as anode active material and graphene sheets as cathode active material. One cell has an anode prepared by a conventional slurry coating process and the other cell has a semi-solid anode prepared according to the method according to the invention. Again, quasi-solid electrode-based cells offer significantly higher energy densities and higher power densities. Lithium ion capacitors were found to follow a similar trend.

Reporting energy and power densities per weight of the active material alone on Ragone plots, as many researchers do, may not give a realistic picture of the performance of the assembled supercapacitor cells. It would be important to point out The weight of other device components must also be taken into account. These overhead components, including current collectors, electrolytes, separators, binders, connectors, and packaging, are non-active materials and do not contribute to charge storage mass. These components only add weight and volume to the device. Therefore, it is desirable to reduce the relative proportions of weight of overhead components and increase the percentage of active material. However, it has not been possible to achieve this goal using conventional battery manufacturing methods. The present invention overcomes this longstanding and most serious problem in the lithium battery art.

In commercial lithium-ion batteries with an electrode thickness of 100-200 μm, the weight ratio of anode active material (e.g., graphite or carbon) in lithium-ion batteries is typically 12-17%, and that of cathode active material. The weight ratio (for inorganic materials such as LiMn ₂ O ₄ ) is between 22% and 41%, or between 10% and 15% for organic or polymeric materials. Therefore, a factor of 3-4 is frequently used to extrapolate the energy or power density of a device (cell) from properties based on active material weight alone. In most scientific papers, the properties reported are typically based on active material weight only, and the electrodes are typically very thin (<<100 μm, and often <<50 μm). The active material weight is typically 5%-10% of the total device weight, which is the actual cell (device) energy or power density by dividing the corresponding active material weight base value by a factor of 10-20. suggests that we can obtain After this factor is taken into account, the properties reported in these papers are unlikely to be better than those of commercial batteries. Therefore, great caution must be exercised in reading and interpreting battery performance data reported in scientific papers and patent applications.

Claims (88)

(a) 30% to 95% by volume of a cathode active material, 5% to 40% by volume of a first electrolyte containing an alkali salt dissolved in a solvent, and 0.01% to 30% by volume of a semi-solid cathode containing a conductive additive, said conductive additive containing conductive filaments forming a 3D network of electron-conducting pathways, the semi-solid electrode having a capacity of 10 ⁻⁶ S/cm˜300 S a quasi-solid cathode having a conductivity of /cm ;
(b) an anode;
(c) an alkali metal cell comprising an ion-conducting membrane or porous separator disposed between said anode and said semi-solid cathode, wherein said semi-solid cathode has a thickness of 200 μm or more; alkali metal cell. The alkali metal cell of claim 1, wherein the anode comprises 30% to 95% by volume of anode active material and 5% to 40% by volume of a second electrolyte containing an alkali salt dissolved in a solvent. and from 0.01% to 30% by volume of a conductive additive, said conductive additive containing conductive filaments forming a 3D network of electronic conduction paths, said An alkali metal cell, characterized in that the quasi-solid electrode has a conductivity between 10 ⁻⁶ S/cm and 300 S/cm and the quasi-solid anode has a thickness of 200 μm or more. (a) 30% to 95% by volume of an anode active material, 5% to 40% by volume of an electrolyte containing an alkali salt dissolved in a solvent, and 0.01% to 30% by volume of a conductive additive; wherein the conductive additive containing conductive filaments forms a 3D network of electron conducting pathways, the quasi-solid electrode comprising 10 ⁻⁶ S/cm to 300 S/cm a quasi-solid anode having a conductivity of cm ;
(b) a cathode;
(c) an alkali metal cell comprising an ion-conducting membrane or porous separator disposed between said quasi-solid anode and said cathode , wherein said quasi-solid anode has a thickness of 200 μm or more; alkali metal cell. 2. The alkali metal cell of claim 1, wherein the first electrolyte is a quasi-solid electrolyte containing a lithium salt or sodium salt dissolved in a liquid solvent at a salt concentration of 2.5 M or higher. alkali metal cell. 3. The alkali metal cell of claim 2, wherein the first electrolyte or second electrolyte is a semi-solid electrolyte containing a lithium salt or sodium salt dissolved in a liquid solvent at a salt concentration of 2.5 M or higher. An alkali metal cell characterized by: 4. An alkali metal cell according to claim 3, characterized in that the electrolyte is a quasi-solid electrolyte containing a lithium or sodium salt dissolved in a liquid solvent at a salt concentration of 2.5 M or more. . The alkali metal cell of claim 1, wherein the first electrolyte is a semi-solid electrolyte containing a lithium or sodium salt dissolved in a liquid solvent at a salt concentration of 3.0M to 14M. alkali metal cell. 3. The alkali metal cell of claim 2, wherein the first electrolyte or second electrolyte is a semi-solid electrolyte containing a lithium salt or sodium salt dissolved in a liquid solvent at a salt concentration of 3.0M to 14M. An alkali metal cell characterized by: An alkali metal cell according to claim 3, characterized in that the electrolyte is a quasi-solid electrolyte containing a lithium or sodium salt dissolved in a liquid solvent at a salt concentration of 3.0M to 14M. cell. 2. The alkali metal cell of claim 1, wherein the conductive filaments are carbon fibers, graphite fibers, carbon nanofibers, graphite nanofibers, carbon nanotubes, needle coke, carbon whiskers, conductive polymer fibers, conductive material-coated fibers. , metal nanowires, metal fibers, metal wires, graphene sheets, expanded graphite platelets, combinations thereof, or combinations thereof with non-filamentary conductive particles. An alkali metal cell according to claim 1, characterized in that said electrodes maintain a conductivity between 10 ^-5 S/cm and 100 S/cm . An alkali metal cell according to claim 1, characterized in that said electrodes maintain a conductivity between 10 ^-3 S/cm and 10 S/cm . An alkali metal cell according to claim 1, characterized in that said electrodes maintain a conductivity between 10 ^-2 S/cm and 10 S/cm . 2. An alkali metal cell according to claim 1, wherein said conductive filaments are bonded together by a resin at the crossing points between said conductive filaments. 2. An alkali metal cell according to claim 1, wherein the semi-solid cathode contains 0.1% to 20% by volume of a conductive additive. 2. An alkali metal cell according to claim 1, wherein the semi-solid cathode contains 1% to 10% by volume of a conductive additive. An alkali metal cell according to claim 1, characterized in that the amount of said active material is between 40% and 90% by volume of the material of said electrodes . An alkali metal cell according to claim 1, characterized in that the amount of said active material is between 50% and 85% by volume of the material of said electrodes . An alkali metal cell according to claim 1, characterized in that the amount of said active material is between 50% and 75% by volume of the material of said electrodes . 2. The alkali metal cell of claim 1, wherein said first electrolyte is supersaturated. 3. An alkali metal cell according to claim 2, wherein said first electrolyte or said second electrolyte is in a supersaturated state. 2. The alkali metal cell of claim 1, wherein the first electrolyte comprises an aqueous liquid, an organic solvent, an ionic liquid, or a mixture of an organic solvent and an ionic liquid. 3. The alkali metal cell of claim 2, wherein the first electrolyte or the second electrolyte contains an aqueous liquid, an organic solvent, an ionic liquid, or a mixture of an organic solvent and an ionic liquid. alkali metal cell. 3. The alkali metal cell of claim 2, wherein the alkali metal cell is a lithium metal cell, a lithium ion cell, or a lithium ion capacitor cell, and the anode active material comprises:
(a) particles of lithium metal or lithium metal alloy;
(b) natural graphite particles, artificial graphite particles, mesocarbon microbeads (MCMB), carbon particles, needle coke, carbon nanotubes, carbon nanofibers, carbon fibers, and graphite fibers;
(c) silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), nickel (Ni), cobalt ( Co), manganese (Mn), titanium (Ti), iron (Fe), and cadmium (Cd);
(d) alloys or intermetallic compounds of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, or Cd with other elements, stoichiometric or non-stoichiometric; an intermetallic compound;
(e) Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ni, Co, Ti, Mn, or Cd oxides, carbides, nitrides, sulfides, phosphides, selenides, and Tellurides, and mixtures or composites thereof;
(f) prelithiated versions thereof;
(g) prelithiated graphene sheets;
and combinations thereof. 25. The alkali metal cell of claim 24, wherein the prelithiated graphene sheets are pure graphene, graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide, hydrogen. prelithiated graphene, nitrided graphene, boron-doped graphene, nitrogen-doped graphene, chemically functionalized graphene, physically or chemically activated or etched versions thereof, or combinations thereof An alkali metal cell characterized by being selected from versions. 3. The alkali metal cell of claim 2, wherein the alkali metal cell is a sodium metal cell or a sodium ion cell, and the anode active material is petroleum coke, carbon black, amorphous carbon, activated carbon, hard carbon, soft Carbon, _templating carbon, hollow carbon nanowires, hollow carbon spheres, _titanates , _{NaTi2 ( PO4 ) 3} , _{Na2Ti3O7 , Na2C8H4O4} , _Na2TP , _{NaxTiO2 (} x=0.2-1.0), Na ₂ C ₈ H ₄ O ₄ , carboxylate-based materials, C ₈ H ₄ Na ₂ O ₄ , C ₈ H ₆ O ₄ , C ₈ H ₅ NaO ₄ , _containing an _{alkaline intercalation compound selected} from _{C8Na2F4O4 , C10H2Na4O8 , C14H4O6 , C14H4Na4O8} , _{or combinations thereof} An alkali metal cell characterized by: 3. The alkali metal cell of claim 2, wherein the alkali metal cell is a sodium metal cell, a sodium ion cell, or a sodium ion capacitor, and the anode active material comprises:
a) particles of sodium metal or sodium metal alloy;
b) natural graphite particles, artificial graphite particles, mesocarbon microbeads (MCMB), carbon particles, needle coke, carbon nanotubes, carbon nanofibers, carbon fibers and graphite fibers;
c) Sodium-doped Silicon (Si), Germanium (Ge), Tin (Sn), Lead (Pb), Antimony (Sb), Bismuth (Bi), Zinc (Zn), Aluminum (Al), Titanium (Ti ), cobalt (Co), nickel (Ni), manganese (Mn), cadmium (Cd), and mixtures thereof;
d) sodium-containing alloys or intermetallic compounds of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Co, Ni, Mn, Cd, and mixtures thereof;
e) sodium-containing oxides, carbides, nitrides, sulfides, phosphides, selenides, tellurium of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ti, Co, Ni, Mn, Cd or antimonides, and mixtures or composites thereof;
f) a sodium salt;
g) an alkali metal cell selected from the group consisting of graphene sheets preloaded with sodium ions, and combinations thereof. 2. The alkali metal cell of claim 1, wherein the alkali metal cell is a lithium metal cell or a lithium ion cell, and the cathode active material is lithium cobaltate, doped lithium cobaltate, lithium nickelate, doped lithium nickelate, lithium manganate, doped lithium manganate, lithium vanadate, doped lithium vanadate, lithium mixed metal oxide, lithium iron phosphate, lithium vanadium phosphate, lithium manganese phosphate, lithium mixed An alkali metal cell comprising a lithium intercalation compound selected from the group consisting of metal phosphates, metal sulfides, and combinations thereof. 2. The alkali metal cell of claim 1, wherein the alkali metal cell is a lithium metal cell or a lithium ion cell, and the cathode active material is an inorganic material, an organic or polymeric material, a metal oxide/phosphate/ An alkali metal cell, characterized in that it contains a lithium intercalation compound or a lithium absorption compound selected from sulfides, or combinations thereof. 30. The alkali metal cell of claim 29, wherein said metal oxide/phosphate/sulfide is lithium cobaltate, lithium nickelate, lithium manganate, lithium vanadate, lithium mixed metal oxide, lithium iron phosphate , lithium manganese phosphate, lithium vanadium phosphate, lithium mixed metal phosphate, transition metal sulfides, and combinations thereof. 30. The alkali metal cell of claim 29, wherein the inorganic material is selected from sulfur, sulfur compounds, lithium polysulfides, transition metal dichalcogenides, transition metal trichalcogenides, or combinations thereof. cell. 30. The alkali metal cell of claim 29, wherein said inorganic material is selected from _TiS2 , _TaS2 , MoS2, _NbSe3 , _{MnO2 , CoO2} , iron oxide, vanadium oxide, or combinations thereof. An alkali metal cell characterized by: _30. The alkali metal cell of claim 29, wherein said metal oxides/phosphates/ _{sulfides are VO2} , _LixVO2 , _{V2O5 , LixV2O5} , _V3O8 , _{Li xV3O8 , LixV3O7 , V4O9 , LixV4O9 , V6O13 , LixV6O13} , _{doped versions thereof} , _{derivatives thereof} , and their and wherein 0.1<x<5 . 30. The alkali metal cell of claim 29, wherein said metal oxides/phosphates/sulfides are layered compounds _LiMO2 , _spinel compounds _LiM2O4 , _olivine compounds _LiMPO4 , silicate compounds _Li2MSiO4 , An alkali metal cell selected from taborite compound _LiMPO4F , borate compound _LiMBO3 , or combinations thereof, wherein M is a transition metal or a mixture of transition metals. 30. The alkali metal cell of claim 29, wherein the inorganic material comprises (a) bismuth selenide or bismuth telluride, (b) transition metal dichalcogenides or trichalcogenides, (c) niobium, zirconium, molybdenum, hafnium, tantalum. , sulfides, selenides, or tellurides of tungsten, titanium, cobalt, manganese, iron, nickel, or transition metals, (d) boron nitride, or (e) combinations thereof. metal cell. 30. The alkali metal cell of claim 29, wherein the organic or polymeric material is poly(anthraquinonyl sulfide) (PAQS), lithium oxocarbon, 3,4,9,10-perylenetetracarboxylic dianhydride ( PTCDA), poly(anthraquinonyl sulfide), pyrene-4,5,9,10-tetraone (PYT), polymer-bound PYT, quino (triazene), redox-active organic material, tetracyanoquinodimethane (TCNQ), Tetracyanoethylene (TCNE), 2,3,6,7,10,11-hexamethoxytriphenylene (HMTP), poly(5-amino-1,4-dihydroxyanthraquinone) (PDAQ), phosphazene disulfide polymer ([(NPS ₂ ) ₃ ]n), lithiated 1,4,5,8-naphthalenetetraol formaldehyde polymer, hexaazatrinaphthylene (HATN), hexaazatriphenylene hexacarbonitrile (HAT(CN) ₆ ), 5- benzylidene hydantoin, isatin lithium salt, pyromellitic diimide lithium salt, tetrahydroxy-p-benzoquinone derivative (THQLi ₄ ), N,N'-diphenyl-2,3,5,6-tetraketopiperazine (PHP), N, N'-diallyl-2,3,5,6-tetraketopiperazine (AP), N,N'-dipropyl-2,3,5,6-tetraketopiperazine (PRP), thioether polymer, quinone compound, 1, 4-benzoquinone, 5,7,12,14-pentacenetetrone (PT), 5-amino-2,3-dihydro-1,4-dihydroxyanthraquinone (ADDAQ), 5-amino-1,4-dihydroxyanthraquinone (ADAQ ), _calixquinone , _{Li4C6O6 , Li2C6O6 , Li6C6O6 ,} or _{combinations thereof} . 37. The alkali metal cell of claim 36, wherein the thioether polymer is poly[methantetriyl-tetra(thiomethylene)] (PMTTM), poly(2,4-dithiopentanylene) (PDTP), poly( A polymer containing ethene-1,1,2,2-tetrathiol) (PETT), a side chain thioether polymer with a backbone consisting of conjugated aromatic moieties and pendant thioether side chains, poly(2-phenyl- 1,3-dithiolane) (PPDT), poly(1,4-di(1,3-dithiolan-2-yl)benzene) (PDDTB), poly(tetrahydrobenzodithiophene) (PTHBDT), poly[1,2 , 4,5-tetrakis(propylthio)benzene] (PTKPTB, or poly[3,4(ethylenedithio)thiophene] (PEDTT). 30. The alkali metal cell of claim 29, wherein the organic material is copper phthalocyanine, zinc phthalocyanine, tin phthalocyanine, iron phthalocyanine, lead phthalocyanine, nickel phthalocyanine, vanadyl phthalocyanine, fluorochrome phthalocyanine, magnesium phthalocyanine, manganese phthalocyanine, dilithium phthalocyanine , phthalocyanine chloroaluminum, cadmium phthalocyanine, chlorogallium phthalocyanine, cobalt phthalocyanine, silver phthalocyanine, metal-free phthalocyanine, chemical derivatives thereof, or combinations thereof. 30. The alkali metal cell of claim 29, wherein said lithium intercalation compound or lithium absorption compound is selected from metal carbides, metal nitrides, metal borides, metal dichalcogenides, or combinations thereof. alkali metal cell. 30. The alkali metal cell of claim 29, wherein the lithium intercalation compound or lithium absorption compound is niobium, zirconium, molybdenum, hafnium, tantalum, tungsten in the form of nanowires, nanodiscs, nanoribbons, or nanoplatelets. , titanium, vanadium, chromium, cobalt, manganese, iron or nickel oxides, dichalcogenides, trichalcogenides, sulfides, selenides or tellurides. 30. The alkali metal cell of claim 29, wherein the lithium intercalation compound or lithium absorption compound comprises (a) bismuth selenide or bismuth telluride, (b) a transition metal dichalcogenide or trichalcogenide, (c) niobium, selected from zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, cobalt, manganese, iron, nickel, or transition metal sulfides, selenides, or tellurides, (d) boron nitride, or (e) combinations thereof nanodiscs, nanoplatelets, nanocoatings or nanosheets of inorganic materials, wherein said discs, platelets or sheets have a thickness of less than 100 nm. 2. The alkali metal cell of claim 1, wherein the alkali metal cell is a sodium metal cell or a sodium ion cell, and the active material is an inorganic material, an organic or polymeric material, a metal oxide/phosphate/sulfide. An alkali metal cell, characterized in that it is a cathode active material containing a sodium intercalating compound or a sodium absorbing compound selected from , or combinations thereof. 43. The alkali metal cell of claim 42, wherein said metal oxide/phosphate/sulfide is sodium cobaltate, sodium nickelate, sodium manganate, sodium vanadate, sodium mixed metal oxide, sodium/potassium transition Metal oxides, sodium iron phosphate, sodium/potassium iron phosphate, sodium manganese phosphate, sodium/potassium manganese phosphate, sodium vanadium phosphate, sodium/potassium vanadium phosphate, sodium mixed metal phosphate, transition metal sulfide or combinations thereof. 43. The alkali metal cell of claim 42, wherein the inorganic material is selected from sulfur, sulfur compounds, lithium polysulfides, transition metal dichalcogenides, transition metal trichalcogenides, or combinations thereof. cell. 43. The alkali metal cell of claim 42, wherein said inorganic material is selected from _TiS2 , _TaS2 , MoS2, _NbSe3 , _{MnO2 , CoO2} , iron oxide, vanadium oxide, or combinations thereof. An alkali metal cell characterized by: 43. The alkali metal cell of claim 42, wherein the alkali metal cell is a sodium metal cell or a sodium ion cell, and the active materials are _NaFePO4 , Na _{(1-x) KxPO4 , Na0.7} . _FePO4 , _{Na1.5VOPO4F0.5} , _{Na3V2 ( PO4} ) _{3 , Na3V2 ( PO4} ) _2F3 , _Na2FePO4F , _{NaFeF3 , NaVPO4F , Na 3V2 ( PO4 ) 2F3 , Na1.5VOPO4F0.5 , Na3V2 ( PO4 ) 3 , NaV6O15 , NaxVO2 , Na0.33V2O5} , Na _x CoO ₂ , Na _2/3 [Ni _1/3 Mn _2/3 ]O ₂ , Na _x (Fe _1/2 Mn _1/2 )O ₂ , Na _x MnO ₂ , λ-MnO ₂ , Na _x K( _{1 -x) MnO2} , _Na0.44MnO2 , _{Na0.44MnO2 / C} , _Na4Mn9O18 , _{NaFe2Mn ( PO4} ) _{3 , Na2Ti3O7 , Ni1 / 3Mn1} / _3Co1 / _3O2 , _{Cu0.56Ni0.44HCF} , _NiHCF , _NaxMnO2 , _{NaCrO2 , Na3Ti2 (} PO4) _{3 , NiCo2O4 , Ni3} S ₂ /FeS ₂ , Sb ₂ O ₄ , Na ₄ Fe(CN) ₆ /C, NaV _1-x Cr _x PO ₄ F, Se _z Sy ( _y /z=0.01-100), Se, Alode An alkali metal cell characterized by a cathode active material containing a sodium intercalation compound selected from stones, or combinations thereof, wherein x is 0.1 to 1.0. The alkali metal cell of claim 1, wherein the anode active material comprises an electrode active material mass loading of greater than 15 mg/ ^cm2 . The alkali metal cell of claim 1, wherein the anode active material comprises an electrode active material mass loading of greater than 20 mg/ ^cm2 . The alkali metal cell of claim 1, wherein the anode active material comprises an electrode active material mass loading of greater than 30 mg/ ^cm2 . In a method of preparing an alkali metal cell with quasi-solid electrodes, comprising:
(d) combining an amount of active material, an amount of electrolyte, and a conductive additive to form a deformable conductive electrode material, said conductive additive containing conductive filaments; the agent forming a 3D network of electron conducting pathways;
(e) forming the electrode material as a quasi-solid electrode, wherein the electrode material has an uninterrupted 3D network of electronic conduction paths such that the electrode maintains a conductivity greater than or equal to 10 ⁻⁶ S/cm; into an electrode shape;
(f) forming a second electrode;
(g) forming an alkali metal cell by combining said quasi-solid electrode and said second electrode. 51. The method of claim 50, wherein the electrolyte is a semi-solid electrolyte containing a lithium or sodium salt dissolved in a liquid solvent at a salt concentration of 2.5M to 14M. 51. The method of claim 50, wherein the electrolyte is a semi-solid electrolyte containing a lithium or sodium salt dissolved in a liquid solvent at a salt concentration of 3.0M to 11M. 51. The method of claim 50, wherein the conductive filaments are carbon fibers, graphite fibers, carbon nanofibers, graphite nanofibers, carbon nanotubes, needle coke, carbon whiskers, conductive polymer fibers, conductive material coated fibers, metal selected from nanowires, metal fibers, metal wires, graphene sheets, expanded graphite platelets, combinations thereof, or combinations thereof with non-filamentary conductive particles. ^{51. The method of claim 50, wherein said electrode maintains a conductivity between 10-5} S /cm and 300 S/cm . 51. The method of claim 50, wherein the deformable electrode material has an apparent viscosity greater than or equal to 10000 Pa-s at an apparent shear rate of 1000s ^-1 . 51. The method of claim 50, wherein the deformable electrode material has an apparent viscosity greater than or equal to 100000 Pa-s at an apparent shear rate of 1000s ^-1 . 51. The method of claim 50, wherein the amount of active material is between 20% and 95% by volume of the electrode material. 51. The method of claim 50, wherein the amount of active material is between 35% and 85% by volume of the electrode material. 51. The method of claim 50, wherein the amount of active material is between 50% and 75% by volume of the electrode material. 51. The method of claim 50, wherein the combining step comprises dispersing the conductive filaments in a liquid solvent to form a homogenous suspension, then adding the active material to the suspension, or dissolving a sodium salt in said liquid solvent of said suspension. 51. The method of claim 50, wherein the step of combining the electrode materials to form a semi-solid electrode comprises dissolving a lithium or sodium salt in a liquid solvent to form an electrolyte having a first salt concentration; thereafter removing a portion of the liquid solvent to increase the salt concentration to obtain a semi-solid electrolyte having a second salt concentration greater than the first concentration and greater than 2.5M. A method characterized by 62. The method of claim 61, wherein the removing step does not cause precipitation or crystallization of the salt and the electrolyte is supersaturated. 62. The method of claim 61, wherein said liquid solvent comprises a mixture of at least a first liquid solvent and a second liquid solvent, said first liquid solvent being more volatile than said second liquid solvent. and wherein said step of removing a portion of said liquid solvent comprises removing said first liquid solvent. 51. The method of claim 50, wherein the alkali metal cell is a lithium metal cell or a lithium ion cell and the active material comprises
(h) particles of lithium metal or lithium metal alloy;
(i) natural graphite particles, artificial graphite particles, mesocarbon microbeads (MCMB), carbon particles, needle coke, carbon nanotubes, carbon nanofibers, carbon fibers, and graphite fibers;
(j) silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), nickel (Ni), cobalt ( Co), manganese (Mn), titanium (Ti), iron (Fe), and cadmium (Cd);
(k) alloys or intermetallic compounds of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, or Cd with other elements, stoichiometric or non-stoichiometric; an intermetallic compound;
(l) Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ni, Co, Ti, Mn, or Cd oxides, carbides, nitrides, sulfides, phosphides, selenides, and Tellurides, and mixtures or composites thereof;
(m) prelithiated versions thereof;
(n) prelithiated graphene sheets;
and combinations thereof. 65. The method of claim 64, wherein the prelithiated graphene sheets are pure graphene, graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide, graphene hydride. from prelithiated versions of , nitrogenated graphene, boron-doped graphene, nitrogen-doped graphene, chemically functionalized graphene, physically or chemically activated or etched versions thereof, or combinations thereof A method characterized by being selected. 51. The method of claim 50, wherein the alkali metal cell is a sodium metal cell or a sodium ion cell and the active material is petroleum coke, amorphous carbon, activated carbon, hard carbon, soft carbon, template carbon, hollow Carbon nanowires, hollow carbon spheres, titanates, NaTi ₂ (PO ₄ ) ₃ , Na ₂ Ti ₃ O ₇ , Na ₂ C ₈ H ₄ O ₄ , Na ₂ TP, Na _x TiO ₂ (x=0.2~ _{1.0 ) , Na2C8H4O4 , carboxylate - based materials , C8H4Na2O4 , C8H6O4 , C8H5NaO4 , C8Na2F4} an anode active material containing an alkali intercalation compound selected from O ₄ , C ₁₀ H ₂ Na ₄ O ₈ , C ₁₄ H ₄ O ₆ , C ₁₄ H ₄ Na ₄ O ₈ , or combinations thereof; A method characterized by 51. The method of claim 50, wherein the alkali metal cell is a sodium metal cell or a sodium ion cell and the active material comprises
h) particles of sodium metal or sodium metal alloy;
i) natural graphite particles, artificial graphite particles, mesocarbon microbeads (MCMB), carbon particles, needle coke, carbon nanotubes, carbon nanofibers, carbon fibers, and graphite fibers;
j) Sodium-doped Silicon (Si), Germanium (Ge), Tin (Sn), Lead (Pb), Antimony (Sb), Bismuth (Bi), Zinc (Zn), Aluminum (Al), Titanium (Ti ), cobalt (Co), nickel (Ni), manganese (Mn), cadmium (Cd), and mixtures thereof;
k) sodium-containing alloys or intermetallic compounds of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Co, Ni, Mn, Cd, and mixtures thereof;
l) sodium-containing oxides, carbides, nitrides, sulfides, phosphides, selenides, tellurium of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ti, Co, Ni, Mn, Cd or antimonides, and mixtures or composites thereof;
m) a sodium salt;
n) an anode active material selected from the group consisting of graphene sheets preloaded with sodium ions, and combinations thereof. 51. The method of claim 50, wherein the alkali metal cell is a lithium metal cell or a lithium ion cell and the active material is lithium cobaltate, doped lithium cobaltate, lithium nickelate, doped nickelate. Lithium, lithium manganate, doped lithium manganate, lithium vanadate, doped lithium vanadate, lithium mixed metal oxide, lithium iron phosphate, lithium vanadium phosphate, lithium manganese phosphate, lithium mixed metal phosphate A method comprising a cathode active material containing a lithium intercalation compound selected from the group consisting of salts, metal sulfides, and combinations thereof. 51. The method of claim 50, wherein the electrolyte is selected from aqueous liquids, organic solvents, ionic liquids, or mixtures of organic solvents and ionic liquids. 51. The method of claim 50, wherein the alkali metal cell is a lithium metal cell or a lithium ion cell, and the active material is an inorganic material, an organic or polymeric material, a metal oxide/phosphate/sulfide, or a cathode active material containing a lithium intercalation compound or a lithium absorption compound selected from a combination thereof. 71. The method of claim 70, wherein the metal oxide/phosphate/sulfide is lithium cobaltate, lithium nickelate, lithium manganate, lithium vanadate, lithium mixed metal oxide, lithium iron phosphate, phosphorus selected from lithium manganese oxide, lithium vanadium phosphate, lithium mixed metal phosphates, transition metal sulfides, or combinations thereof. 71. The method of claim 70, wherein the inorganic material is selected from sulfur, sulfur compounds, lithium polysulfides, transition metal dichalcogenides, transition metal trichalcogenides, or combinations thereof. 71. The method of claim 70, wherein the inorganic material is selected from _TiS2 , _TaS2 , MoS2, _NbSe3 , _{MnO2 , CoO2} , iron oxide, vanadium oxide, or combinations thereof. how to. _{71. The} method of claim 70, wherein the metal oxide/phosphate/ _sulfide is _VO2 , _{LixVO2 , V2O5 , LixV2O5} , _V3O8 , _{LixV 3O8} , _{LixV3O7 , V4O9 , LixV4O9 , V6O13 , LixV6O13} , _{doped versions thereof} , _{derivatives thereof} , and combinations thereof and wherein 0.1<x<5. 71. The method of claim 70, wherein the metal oxides/phosphates/sulfides are layered compounds _LiMO2 , _spinel compounds _LiM2O4 , olivine compounds _LiMPO4 , silicate compounds _Li2MSiO4 , _taborite compounds. A method, wherein M is a transition metal or a mixture of transition metals selected from LiMPO ₄ F, a borate compound LiMBO ₃ , or a combination thereof. 71. The method of claim 70, wherein the inorganic material is (a) bismuth selenide or bismuth telluride, (b) transition metal dichalcogenides or trichalcogenides, (c) niobium, zirconium, molybdenum, hafnium, tantalum, tungsten. , sulfides, selenides, or tellurides of titanium, cobalt, manganese, iron, nickel, or transition metals, (d) boron nitride, or (e) combinations thereof. 71. The method of claim 70, wherein the organic or polymeric material is poly(anthraquinonyl sulfide) (PAQS), lithium oxocarbon, 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA). , poly(anthraquinonyl sulfide), pyrene-4,5,9,10-tetraone (PYT), polymer-bound PYT, quino (triazene), redox-active organic material, tetracyanoquinodimethane (TCNQ), tetracyano Ethylene (TCNE), 2,3,6,7,10,11-hexamethoxytriphenylene (HMTP), poly(5-amino-1,4-dihydroxyanthraquinone) (PDAQ), phosphazene disulfide polymer ([(NPS ₂ ) ₃ ]n), lithiated 1,4,5,8-naphthalenetetraol formaldehyde polymer, hexaazatrinaphthylene (HATN), hexaazatriphenylene hexacarbonitrile (HAT(CN) ₆ ), 5-benzylidenehydantoin , isatin lithium salt, pyromellitic diimide lithium salt, tetrahydroxy-p-benzoquinone derivative (THQLi ₄ ), N,N′-diphenyl-2,3,5,6-tetraketopiperazine (PHP), N,N′ - diallyl-2,3,5,6-tetraketopiperazine (AP), N,N'-dipropyl-2,3,5,6-tetraketopiperazine (PRP), thioether polymer, quinone compound, 1,4- benzoquinone, 5,7,12,14-pentacentetrone (PT), 5-amino-2,3-dihydro-1,4-dihydroxyanthraquinone (ADDAQ), 5-amino-1,4-dihydroxyanthraquinone (ADAQ), _selected from _calixquinone , _Li4C6O6 , _{Li2C6O6 , Li6C6O6 ,} or _{combinations thereof} . 78. The method of claim 77, wherein the thioether polymer is poly[methantetriyl-tetra(thiomethylene)] (PMTTM), poly(2,4-dithiopentanylene) (PDTP), poly(ethene- 1,1,2,2-tetrathiol) (PETT), a side chain thioether polymer with a backbone consisting of conjugated aromatic moieties and pendant thioether side chains, poly(2-phenyl-1, 3-dithiolane) (PPDT), poly(1,4-di(1,3-dithiolan-2-yl)benzene) (PDDTB), poly(tetrahydrobenzodithiophene) (PTHBDT), poly[1,2,4 ,5-tetrakis(propylthio)benzene] (PTKPTB, or poly[3,4(ethylenedithio)thiophene] (PEDTT). 71. The method of claim 70, wherein the organic material is copper phthalocyanine, zinc phthalocyanine, tin phthalocyanine, iron phthalocyanine, lead phthalocyanine, nickel phthalocyanine, vanadyl phthalocyanine, fluorochrome phthalocyanine, magnesium phthalocyanine, manganese phthalocyanine, dilithium phthalocyanine, phthalocyanine A method comprising a phthalocyanine compound selected from chloroaluminum, cadmium phthalocyanine, chlorogallium phthalocyanine, cobalt phthalocyanine, silver phthalocyanine, metal-free phthalocyanine, chemical derivatives thereof, or combinations thereof. 71. The method of claim 70, wherein the lithium intercalating compound or lithium absorbing compound is selected from metal carbides, metal nitrides, metal borides, metal dichalcogenides, or combinations thereof. . 71. The method of claim 70, wherein the lithium intercalating compound or lithium absorbing compound is niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium in the form of nanowires, nanodiscs, nanoribbons, or nanoplatelets. , vanadium, chromium, cobalt, manganese, iron or nickel oxides, dichalcogenides, trichalcogenides, sulfides, selenides or tellurides. 71. The method of claim 70, wherein the lithium intercalating compound or lithium absorbing compound comprises (a) bismuth selenide or bismuth telluride, (b) transition metal dichalcogenides or trichalcogenides, (c) niobium, zirconium, an inorganic material selected from molybdenum, hafnium, tantalum, tungsten, titanium, cobalt, manganese, iron, nickel, or transition metal sulfides, selenides, or tellurides; (d) boron nitride; or (e) combinations thereof A method selected from nanodiscs, nanoplatelets, nanocoatings or nanosheets of material, wherein the thickness of said discs, platelets or sheets is less than 100 nm. 71. The method of claim 70, wherein the lithium intercalating compound or lithium absorbing compound comprises (i) bismuth selenide or bismuth telluride, (ii) transition metal dichalcogenides or trichalcogenides, (iii) niobium, zirconium, lithium selected from molybdenum, hafnium, tantalum, tungsten, titanium, cobalt, manganese, iron, nickel, or transition metal sulfides, selenides, or tellurides; (iv) boron nitride; or (v) combinations thereof A method comprising nanodiscs, nanoplatelets, nanocoatings or nanosheets of an intercalation compound, wherein the thickness of said discs, platelets, coatings or sheets is less than 100 nm. 51. The method of claim 50, wherein the alkali metal cell is a sodium metal cell or a sodium ion cell, and the active material is an inorganic material, an organic or polymeric material, a metal oxide/phosphate/sulfide, or a cathode active material containing a sodium intercalating compound or a sodium absorbing compound selected from or combinations thereof. 85. The method of claim 84, wherein the metal oxide/phosphate/sulfide is sodium cobaltate, sodium nickelate, sodium manganate, sodium vanadate, sodium mixed metal oxide, sodium/potassium transition metal oxide. sodium iron phosphate, sodium/potassium iron phosphate, sodium manganese phosphate, sodium/potassium manganese phosphate, sodium vanadium phosphate, sodium/potassium vanadium phosphate, sodium mixed metal phosphate, transition metal sulfide, or combinations thereof. 85. The method of claim 84, wherein the inorganic material is selected from sulfur, sulfur compounds, lithium polysulfides, transition metal dichalcogenides, transition metal trichalcogenides, or combinations thereof. 85. The method of claim 84, wherein the inorganic material is selected from _TiS2 , _TaS2 , MoS2, _NbSe3 , _{MnO2 , CoO2} , iron oxide, vanadium oxide, or combinations thereof. how to. 51. The method of claim 50, wherein the alkali metal cell is a sodium metal cell or a sodium ion cell and the active material is _NaFePO4 , Na _{(1-x) KxPO4 , Na0.7FePO4 .} , _{Na1.5VOPO4F0.5 , Na3V2 ( PO4} ) ₃ , _{Na3V2 ( PO4} ) _{2F3 , Na2FePO4F} , _{NaFeF3 , NaVPO4F , Na3V 2 ( PO4} ) _{2F3 , Na1.5VOPO4F0.5} , _{Na3V2 ( PO4 ) 3} , _{NaV6O15 , NaxVO2 , Na0.33V2O5 , Na x} CoO ₂ , Na _2/3 [Ni _1/3 Mn _2/3 ]O ₂ , Na _x (Fe _1/2 Mn _1/2 )O ₂ , Na _x MnO ₂ , λ-MnO ₂ , Na _x K _{( 1 -x) MnO2} , _Na0.44MnO2 , _Na0.44MnO2 / _C , _Na4Mn9O18 , _{NaFe2Mn (} PO4) _{3 , Na2Ti3O7 , Ni1 / 3 Mn1} / _3Co1 / _3O2 , _{Cu0.56Ni0.44HCF} , _NiHCF , _NaxMnO2 , _{NaCrO2 , Na3Ti2 ( PO4} ) _{3 , NiCo2O4 , Ni3S2} /FeS ₂ , Sb ₂ O ₄ , Na ₄ Fe(CN) ₆ /C , NaV _1-x Cr _x PO ₄ F, Se _z Sy ( _y /z = 0.01 to 100), Se, aluordite, or a cathode active material containing a sodium intercalation compound selected from or combinations thereof, wherein x is 0.1 to 1.0.

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