CN110692152B

CN110692152B - Alkali metal cell with deformable quasi-solid electrode material

Info

Publication number: CN110692152B
Application number: CN201880033563.7A
Authority: CN
Inventors: 阿茹娜·扎姆; 张博增
Original assignee: Nanotek Instruments Inc
Current assignee: Nanotek Instruments Inc
Priority date: 2017-05-24
Filing date: 2018-03-13
Publication date: 2023-08-15
Anticipated expiration: 2038-03-13
Also published as: JP7175284B2; JP2020522839A; CN110692152A; WO2018217274A1; KR20200010312A

Abstract

An alkali metal cell and a method of making the alkali metal cell with a quasi-solid electrode are provided, the method comprising: (a) Combining an amount of active material, an amount of electrolyte, and a conductive additive to form a deformable and conductive electrode material, wherein the conductive additive comprising conductive filaments forms a 3D network of electron conduction pathways; (b) Forming the electrode material into a quasi-solid electrode, wherein the forming step includes deforming the electrode material into an electrode shape without interrupting a 3D network of the electron conduction paths, thereby maintaining the electrode at not less than 10 ^‑6 Conductivity of S/cm; (c) forming a second electrode; and (d) forming an alkali metal cell by combining the quasi-solid electrode and the second electrode, the alkali metal cell having an ion-conducting membrane disposed between the two electrodes.

Description

Alkali metal cell with deformable quasi-solid electrode material

Cross Reference to Related Applications

The present application claims priority from U.S. patent application Ser. No. 15/604,606 filed on 5.24 and U.S. patent application Ser. No. 15/604,607 filed on 5.24, 2017, which are incorporated herein by reference.

Technical Field

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

Background

Historically, the most popular rechargeable energy storage devices of today, lithium ion batteries, have actually evolved from rechargeable "lithium metal batteries" that use lithium (Li) metal or Li alloys as the anode and Li intercalation compounds as the cathode. Li metal is an ideal anode material due to its light weight (the lightest metal), high electronegativity (3.04V relative to standard hydrogen electrodes), and high theoretical capacity (3,860mAh/g). Based on these outstanding characteristics, lithium metal batteries were proposed as ideal systems for high energy density applications 40 years ago. In the middle of the 1980 s, several prototypes of rechargeable Li metal batteries were developed. A notable example is a battery consisting of a Li metal anode and a molybdenum sulfide cathode developed by MOLI Energy, inc (inc.). Such cells and several other cells from different manufacturers were abandoned due to a series of safety problems caused by the drastic non-uniformity of Li growth (formation of Li dendrites) when the metal was re-electroplated during each subsequent recharging cycle. As the number of cycles increases, these dendritic or arborescent Li structures may eventually pass through the separator to the cathode, causing internal shorting.

To overcome these safety problems, several alternative methods have been proposed in which the electrolyte or anode is modified. One approach involves replacing the Li metal with graphite (another Li intercalation material) as the anode. The operation of such a battery involves shuttling Li ions between two Li-intercalation compounds, and is therefore referred to as a "Li-ion battery". It is speculated that Li-ion batteries are inherently safer than Li-metal batteries because Li exists in its ionic rather than metallic state.

Lithium ion batteries are the primary candidate energy storage devices for Electric Vehicles (EVs), renewable energy storage, and smart grid applications. The last two decades have witnessed a continual improvement in energy density, rate capability and safety of Li-ion batteries, but Li-metal batteries with significantly higher energy densities have been largely ignored for some reason. However, the use of graphite-based anodes in Li-ion batteries has several significant drawbacks: low specific capacity (theoretical capacity 372mAh/g, 3,860mAh/g compared to Li metal), long Li intercalation times (e.g., low solid state diffusion coefficient of Li into and out of graphite and inorganic oxide particles) require long recharging times (e.g., 7 hours for electric vehicle batteries), inability to deliver high pulse power (power density < <1 kW/kg), and the need to use pre-lithiated cathodes (e.g., lithium cobalt oxide), thereby limiting the choice of available cathode materials. Moreover, these commonly used cathodes have a relatively low specific capacity (typically <200 mAh/g). These factors have caused two major drawbacks of today's Li-ion batteries-low gravimetric energy density and volumetric energy density (typically 150-220Wh/kg and 450-600 Wh/L) and low power density (typically <0.5kW/kg and <1.0 kW/L), all based on total battery cell weight or volume.

The emerging EV and renewable energy industries require the availability of rechargeable batteries with significantly higher gravimetric energy densities (e.g., requirements >250Wh/kg and preferably >300 Wh/kg) and higher power densities (shorter recharging times) than current Li-ion battery technology can provide. Furthermore, the microelectronics industry requires batteries with significantly greater volumetric energy densities (> 650Wh/L, preferably >750 Wh/L) because consumers need to have smaller and more compact portable devices (e.g., smartphones and tablet computers) that store more energy. These requirements have led to considerable research efforts to develop electrode materials for lithium ion batteries with higher specific capacities, excellent rate performance and good cycling stability.

Several elements from groups III, IV and V of the periodic table can alloy with Li at certain desired voltages. Thus, it has been proposed thatVarious anode materials based on such elements and some metal oxides are used in lithium ion batteries. Among these, silicon has been considered as one of the next-generation anode materials for high-energy lithium ion batteries because it has a theoretical gravimetric capacity (based on Li) that is nearly 10 times higher than graphite _3.75 Si 3,560 mAh/g vs LiC ₆ 372 mAh/g) and about 3 times larger volume capacity. However, significant volume changes in Si (up to 380%) often lead to severe and rapid battery performance degradation during lithium ion alloying and dealloying (cell charging and discharging). Performance degradation is mainly due to comminution caused by the volume change of Si and the inability of the binder/conductive additive to maintain electrical contact between the comminuted Si particles and the current collector. In addition, the inherently low conductivity of silicon is another challenge to be addressed.

Although several high capacity anode active materials (e.g., si) have been discovered, there is no corresponding high capacity cathode material available. The cathode active materials commonly used in Li-ion batteries currently have the following serious drawbacks:

(1) The practical capacities that can be achieved with current cathode materials (e.g., lithium iron phosphate and lithium transition metal oxides) have been limited to the range of 150-250mAh/g, and in most cases, less than 200mAh/g.

(2) The insertion and extraction of lithium into and out of these commonly used cathodes is dependent on the fact that Li has a very low diffusion coefficient (typically 10 ^-8 To 10 ^-14 cm ² /s) of the solid particles (resulting in a very low power density (another long standing problem of today's lithium ion batteries)).

(3) Current cathode materials are electrically and thermally insulating and do not transport electrons and heat effectively and efficiently. Low conductivity means high internal resistance and the need to add large amounts of conductive additives, effectively reducing the proportion of electrochemically active material in a cathode that already has low capacity. The low thermal conductivity also means a higher tendency to undergo thermal runaway, which is a major safety issue in the lithium battery industry.

The low capacity anode or cathode active material is not lithiumThe only problem faced by the ion battery industry. There are serious design and manufacturing problems that the lithium ion battery industry does not seem to recognize or to a great extent ignore. For example, despite the high gravimetric capacity at the electrode level (based on the anode or cathode active material weight alone) as often required in publications and patent documents, these electrodes unfortunately do not provide a battery with high capacity at the battery cell or stack level (based on the total battery cell weight or stack weight). This is due to the following point: in these reports, the actual active material mass loading of the electrode is too low. In most cases, the active material mass loading (areal density) of the anode was significantly lower than 15mg/cm ² And most of them<8mg/cm ² (areal density = amount of active material per cross-sectional area of the electrode along the thickness of the electrode). The amount of the cathode active material is typically 1.5 to 2.5 times higher than that of the anode active material. As a result, the weight proportion of the anode active material (e.g., graphite or carbon) in the lithium ion battery is typically from 12% to 17%, and the cathode active material (e.g., liMn ₂ O ₄ ) Is from 17 to 35% by weight (most<30%). The weight fraction of the combined cathode active material and anode active material is typically from 30% to 45% of the cell weight.

Sodium batteries have been considered as an attractive alternative to lithium batteries as an entirely different class of energy storage devices because of the abundance of sodium content and the significantly more environmentally friendly production of sodium compared to lithium production. In addition, the high cost of lithium is a major problem.

Several groups have described sodium ion batteries using hard carbon based anodes (Na-carbon intercalation compounds) and sodium transition metal phosphates as cathodes. However, these sodium-based devices exhibit even lower specific energy and rate performance than Li-ion batteries. These conventional sodium ion batteries require diffusion of sodium ions into and out of the sodium intercalation compound at both the anode and cathode. The solid state diffusion process of sodium ions in the required sodium ion battery is even slower than the Li diffusion process in the Li ion battery, resulting in an excessively low power density.

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 the anode active material is generally considered undesirable and dangerous due to dendrite formation, interface aging and electrolyte incompatibility issues. Most notably, the same flammable solvents previously used for lithium secondary batteries are also used in most sodium metal or sodium ion batteries.

The low active material mass loading is mainly due to the inability to obtain thicker electrodes (thicker than 100-200 μm) using conventional slurry coating procedures. This is not a trivial task as one might consider, and for the purpose of optimizing cell performance, in fact the electrode thickness is not a design parameter that can be arbitrarily and freely changed. Conversely, thicker samples tend to become extremely brittle or have poor structural integrity, and will also require the use of large amounts of binder resin. The low areal density and low bulk density (associated with thin electrodes and poor packing density) result in relatively low volumetric capacity and low volumetric energy density of the battery cells.

With the increasing demand for more compact and portable energy storage systems, there is a growing interest in improving the utilization of the volume of the battery. Novel electrode materials and designs that enable high volumetric capacity and high mass loadings are critical to achieving improved cell volumetric capacity and energy density.

Thus, there is a clear and urgent need for lithium and sodium batteries having high active material mass loading (high areal density), high electrode thickness without significantly reducing electron and ion transport rates (e.g., with improved conductivity), high capacity, high power density, and high energy density. These batteries must be produced in an environmentally friendly manner.

Disclosure of Invention

The present invention provides a method of producing lithium or sodium batteries having high active material mass loading, exceptionally low non-contributing (excess) weight and volume (relative to active material mass and volume), high capacity, and unprecedented high energy and power densities. The lithium or sodium battery may be a primary (non-rechargeable) or secondary (rechargeable) battery, including rechargeable lithium or sodium metal batteries (with lithium or sodium metal anodes) and lithium ion or sodium ion batteries (e.g., with a first lithium intercalation compound as the anode active material and a second lithium intercalation or absorbing compound having a much higher electrochemical potential than the first lithium intercalation compound as the cathode active material). The alkali metal cell also includes a lithium ion capacitor and a sodium ion capacitor, wherein the anode is a lithium ion or sodium ion cell type anode and the cathode is a supercapacitor cathode (e.g., activated carbon or graphene sheet as an active material used in an electric double layer capacitor or redox quasi-capacitor).

In certain embodiments, the present invention provides an alkali metal cell comprising: (a) A quasi-solid cathode comprising from about 30% to about 95% by volume of a cathode active material, from about 5% to about 40% by volume of a first electrolyte comprising an alkali metal salt dissolved in a solvent, and from about 0.01% to about 30% by volume of a conductive additive, wherein the conductive additive comprising conductive filaments forms a 3D network of electron conduction pathways, whereby the quasi-solid electrode has a molecular weight of from about 10 ^-6 Conductivity of S/cm to about 300S/cm; (b) an anode; and (c) an ion conducting membrane or porous separator disposed between the anode and the quasi-solid cathode; wherein the quasi-solid cathode has a thickness of not less than 200 μm. The quasi-solid cathode preferably contains no small particles

At 10mg/cm ² Preferably not less than 15mg/cm ² More preferably not less than 25mg/cm ² More preferably not less than 35mg/cm ² And still more preferably not less than 45mg/cm ² And most preferably greater than 65mg/cm ² Is used for the cathode active material mass loading.

In the cell, the anode may comprise a quasi-solid anode containing about 30% to about 95% by volume of an anode active material, about 5% to about 40% by volume of a second electrolyte containing an alkali metal salt dissolved in a solvent, and about 0.01% to about 30% by volume of a conductive additive, wherein The conductive additive comprising conductive filaments forms a 3D network of electron conducting pathways, thereby providing the quasi-solid electrode with a specific surface area of from about 10 ^-6 Conductivity of S/cm to about 300S/cm; wherein the quasi-solid anode has a thickness of not less than 200 μm. The quasi-solid anode preferably contains not less than 10mg/cm ² Preferably not less than 15mg/cm ² More preferably not less than 25mg/cm ² More preferably not less than 35mg/cm ² And still more preferably not less than 45mg/cm ² And most preferably greater than 65mg/cm ² Is used for the anode active material mass loading.

In certain embodiments, the present invention provides an alkali metal cell comprising: (A) A quasi-solid anode comprising about 30% to about 95% by volume of an anode active material, about 5% to about 40% by volume of an electrolyte comprising an alkali metal salt dissolved in a solvent, and about 0.01% to about 30% by volume of a conductive additive, wherein the conductive additive comprising conductive filaments forms a 3D network of electron conduction pathways, whereby the quasi-solid electrode has a molecular weight of from about 10 ^-6 Conductivity of S/cm to about 300S/cm; (B) a cathode; and (C) an ion conducting membrane or porous separator disposed between the anode and the quasi-solid cathode; wherein the quasi-solid cathode has a thickness of not less than 200 μm.

The present invention also provides a method of preparing an alkali metal cell having a quasi-solid electrode, the method comprising: (a) Combining an amount of active material (anode active material or cathode active material), an amount of electrolyte, and a conductive additive to form a deformable and conductive electrode material, wherein the conductive additive comprising conductive filaments forms a 3D network of electron conduction pathways; (b) Forming the electrode material into a quasi-solid electrode, wherein the forming step includes deforming the electrode material into an electrode shape without interrupting a 3D network of the electron conduction paths, thereby maintaining the electrode at not less than 10 ^-6 S/cm (preferably not less than 10) ^-5 S/cm, more preferably not less than 10 ^-3 S/cm, further preferably not less than 10 ^-2 S/cm, still more preferably and typically not less than 10 ^-1 S/cm, even more typically and preferably not less than 1S/cm, and still more typically and preferably not less than 10S/cm and up to 300S/cm); (c) Forming a second electrode (the second electrode may be a quasi-solid electrode); and (d) forming an alkali metal cell by combining the quasi-solid electrode and the second electrode, the alkali metal cell having an ion-conducting membrane disposed between the two electrodes.

The electrolyte may be a quasi-solid electrolyte containing a lithium salt or sodium salt dissolved in a liquid solvent, the salt concentration of which is from 2.5M to 14M; preferably greater than 3M, more preferably greater than 3.5M, still more preferably greater than 5M, yet more preferably greater than 7M, and even more preferably greater than 10M. In the case of a salt concentration of not less than 2.5M, the electrolyte is no longer a liquid electrolyte; instead, it is a quasi-solid electrolyte. In certain embodiments, the electrolyte is a quasi-solid electrolyte containing a lithium or sodium salt dissolved in a liquid solvent, having a salt concentration of from 3.0M to 11M.

In certain embodiments, the conductive filaments are selected from 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-filament conductive particles.

In certain embodiments, the electrode is maintained from 10 ^-5 Conductivity of S/cm to about 1S/cm.

In certain embodiments, the deformable electrode material has a thickness of at least 1,000 seconds ^-1 An apparent viscosity of not less than about 10,000Pa-s as measured at an apparent shear rate. In certain embodiments, the deformable electrode material has a thickness of at least 1,000 seconds ^-1 An apparent viscosity of not less than about 100,000Pa-s at an apparent shear rate.

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

Preferably, the step of combining the active material, the conductive additive, and the electrolyte (including dissolving lithium or sodium salt in a liquid solvent) follows a specific order. This step includes first dispersing the conductive filaments into a liquid solvent to form a uniform suspension, then adding the active material to the suspension and dissolving a lithium or sodium salt in the liquid solvent of the suspension. In other words, the conductive filaments must first be uniformly dispersed in the liquid solvent before adding other ingredients, such as active materials, and before dissolving the lithium or sodium salt in the solvent. This sequence is critical to achieving percolation (persistence) of the conductive filaments in order to form a 3D network of electron conducting pathways. Without following this order, percolation of the conductive filaments may not occur or only occur when an excessively large proportion of conductive filaments (e.g., >10% by volume) is added, which would reduce the fraction of active material and thus the energy density of the cell.

In certain embodiments, the step of combining and forming the electrode material into a quasi-solid electrode comprises dissolving a lithium salt or sodium salt in a liquid solvent to form an electrolyte having a first salt concentration and subsequently removing a portion of the liquid solvent to increase the salt concentration, thereby obtaining a quasi-solid electrolyte having a second salt concentration that is higher than the first concentration and preferably higher than 2.5M (and more preferably from 3.0M to 14M).

The step of removing a portion of the solvent may be performed in a manner that does not cause precipitation or crystallization of the salt and the electrolyte is in a supersaturated state. In certain preferred embodiments, the liquid solvent comprises a mixture of at least a first liquid solvent and a second liquid solvent and the first liquid solvent is more volatile than the second liquid solvent, wherein the step of removing a portion of the liquid solvent comprises partially or fully removing the first liquid solvent.

For anode active materials or cathode active materials useful in the practice of the present inventionThe type of the sexual material is not limited. Preferably, however, the anode active material is greater than Li/Li when the battery is charged ⁺ (i.e., relative to Li.fwdarw.Li as a standard potential) ⁺ +e ^- ) Lithium ions are absorbed at electrochemical potentials of less than 1.0 volt, preferably less than 0.7 volt.

In certain preferred embodiments, the alkali metal cell is a lithium metal battery, a lithium ion battery, or a lithium ion capacitor, wherein the anode active material is selected from the group consisting of: (a) particles of lithium metal or lithium metal alloy; (b) Natural graphite particles, artificial graphite particles, mesophase Carbon Microbeads (MCMB), carbon particles (including soft 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); (d) Si, ge, sn, pb, sb, bi, zn, al or Cd with other elements, wherein the alloy or compound is stoichiometric or non-stoichiometric; (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) a prelithiated version thereof; (g) prelithiation of 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 an anode active material containing a sodium intercalation compound selected from the group consisting of: petroleum coke, carbon black, amorphous carbon, activated carbon, hard carbon (carbon that is difficult to graphitize), soft carbon (carbon that can be easily graphitized), template carbon, hollow carbon nanowires, hollow carbon spheres, titanates, niti 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 to 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 、C ₈ Na ₂ F ₄ 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 a combination thereof.

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, artificial graphite particles, mesophase Carbon 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) Si, ge, sn, pb, sb, bi, zn, al, ti, co, ni, mn, cd sodium-containing alloys or intermetallic compounds, and mixtures thereof; (e) Si, ge, sn, pb, sb, bi, zn, al, fe, ti, co, ni, mn, cd sodium-containing oxides, carbides, nitrides, sulfides, phosphides, selenides, tellurides, or antimonides, and mixtures or composites thereof; (f) sodium salt; and (g) 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 material is a cathode active material containing a sodium intercalation compound or sodium absorbing compound selected from the group consisting of: an inorganic material, an organic or polymeric material, a metal oxide/phosphate/sulfide, or a combination thereof. The metal oxide/phosphate/sulfide may be selected from sodium cobalt oxide, sodium nickel oxide, sodium manganese oxide, sodium vanadium oxide, sodium mixed metal oxide, sodium/potassium transition metal oxide, iron sodium phosphate, iron sodium/potassium phosphate, manganese sodium/potassium phosphate, vanadium sodium/potassium phosphate, sodium mixed metal phosphate, transition metal sulfide, or a combination thereof.

The inorganic material may be selected from sulfur, sulfur compounds, lithium polysulfide, and transition metal disulfideA chalcogenide, a transition metal trisulfide, or a combination thereof. In certain embodiments, the inorganic material is selected from TiS ₂ 、TaS ₂ 、MoS ₂ 、NbSe ₃ 、MnO ₂ 、CoO ₂ Iron oxide, vanadium oxide, or a combination thereof.

In some embodiments, the alkali metal cell is a sodium metal cell or a sodium ion cell and the active material is a cathode active material containing a sodium intercalation compound selected from the group consisting of: naFePO ₄ 、Na _(1-x) K _x PO ₄ 、Na _0.7 FePO ₄ 、Na _1.5 VOPO ₄ F _0.5 、Na ₃ V ₂ (PO ₄ ) ₃ 、Na ₃ V ₂ (PO ₄ ) ₂ F ₃ 、Na ₂ FePO ₄ F、NaFeF ₃ 、NaVPO ₄ F、Na ₃ V ₂ (PO ₄ ) ₂ F ₃ 、Na _1.5 VOPO ₄ F _0.5 、Na ₃ V ₂ (PO ₄ ) ₃ 、NaV ₆ O ₁₅ 、Na _x VO ₂ 、Na _0.33 V ₂ O ₅ 、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) MnO ₂ 、Na _0.44 MnO ₂ 、Na _0.44 MnO ₂ /C、Na ₄ Mn ₉ O ₁₈ 、NaFe ₂ Mn(PO ₄ ) ₃ 、Na ₂ Ti ₃ O ₇ 、Ni _1/3 Mn _1/3 Co _1/3 O ₂ 、Cu _0.56 Ni _0.44 HCF、NiHCF、Na _x MnO ₂ 、NaCrO ₂ 、Na ₃ Ti ₂ (PO ₄ ) ₃ 、NiCo ₂ O ₄ 、Ni ₃ S ₂ /FeS ₂ 、Sb ₂ O ₄ 、Na ₄ Fe(CN) ₆ /C、NaV _1-x Cr _x PO ₄ F、Se _z S _y (y/z＝0.01 to 100), se, dawsonite (alaluaudiotes), or combinations thereof, wherein x is from 0.1 to 1.0.

In some preferred embodiments, the cathode active material contains a lithium intercalation compound selected from the group consisting of: lithium cobalt oxide, doped lithium cobalt oxide, lithium nickel oxide, doped lithium nickel oxide, lithium manganese oxide, doped lithium manganese oxide, lithium vanadium oxide, doped lithium vanadium oxide, lithium mixed metal oxide, lithium iron phosphate, lithium vanadium phosphate, lithium manganese phosphate, lithium mixed metal phosphate, metal sulfide, and combinations thereof.

The electrolyte may be an aqueous liquid, an organic liquid, an ionic liquid (an ionic salt having a melting temperature below 100 ℃, preferably below room temperature of 25 ℃) or a mixture of ionic liquid and organic liquid in a ratio of from 1/100 to 100/1. Organic liquids are desirable, but ionic liquids are preferred.

In a preferred embodiment, the quasi-solid electrode has a thickness of from 200 μm to 1cm, preferably from 300 μm to 0.5cm (5 mm), further preferably from 400 μm to 3mm, and most preferably from 500 μm to 2.5mm (2,500 μm). If the active material is an anode active material, the anode active material has a concentration of not less than 25mg/cm ² (preferably not less than 30 mg/cm) ² And more preferably not less than 35mg/cm ² ) And/or at least 25% (preferably at least 30% and more preferably at least 35%) by weight or by volume of the total battery cell. If the active material is a cathode active material, the cathode active material preferably has a concentration of not less than 20mg/cm for organic or polymeric materials in the cathode ² (preferably not less than 25 mg/cm) ² And more preferably not less than 30mg/cm ² ) Or not less than 45mg/cm for inorganic and non-polymeric materials ² (preferably not less than 50 mg/cm) ² And more preferably not less than 55mg/cm ² ) And/or a mass loading of at least 45% (preferably at least 50% and more preferably at least 55%) by weight or by volume of the entire battery cell.

The above requirements for electrode thickness, anode active material face mass loading or mass fraction relative to the entire battery cell, or cathode active material face mass loading or mass fraction relative to the entire battery cell are not possible with conventional lithium or sodium batteries using conventional slurry coating and drying processes.

In some embodiments, the anode active material is a prelithiated version of a graphene sheet selected from pristine graphene, graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide, hydrogenated graphene, nitrogenated graphene, boron doped graphene, nitrogen doped graphene, chemically functionalized graphene, physically or chemically activated or etched versions thereof, or combinations thereof. Surprisingly, the resulting lithium battery cells did not exhibit satisfactory cycle life (i.e., rapid capacity decay) without pre-lithiation.

In some embodiments of the methods of the present invention, the cell is a lithium metal cell or lithium ion cell containing a cathode active material selected from a lithium intercalation compound or lithium absorbing compound selected from an inorganic material, an organic or polymeric material, a metal oxide/phosphate/sulfide, or a combination thereof. For example, the metal oxide/phosphate/sulfide may be selected from lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium vanadium oxide, lithium mixed metal oxide, lithium iron phosphate, lithium manganese phosphate, lithium vanadium phosphate, lithium mixed metal phosphate, transition metal sulfide, or a combination thereof. The inorganic material is selected from sulfur, sulfur compounds, lithium polysulfide, transition metal dichalcogenides, transition metal trisulfide, or combinations thereof. Specifically, the inorganic material is selected from TiS ₂ 、TaS ₂ 、MoS ₂ 、NbSe ₃ 、MnO ₂ 、CoO ₂ Iron oxide, vanadium oxide, or a combination thereof. These will be discussed further later.

In the lithium metal battery, the cathode active material contains a lithium intercalation compound selected from a metal carbide, a metal nitride, a metal boride, a metal dichalcogenide, or a combination thereof. In some embodiments, the cathode active material contains a lithium intercalation compound selected from: an oxide, dichalcogenide, trichalcogenide, sulfide, selenide, or telluride of niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, vanadium, chromium, cobalt, manganese, iron, or nickel in the form of nanowires, nanoplates, nanoribbons, or nanoplatelets. Preferably, the cathode active material contains a lithium intercalation compound selected from nano-discs, nano-platelets, nano-coatings or nano-platelets of an inorganic material selected from: (a) bismuth selenide or bismuth telluride, (b) a transition metal di-or tri-chalcogenide, (c) a sulfide, selenide, or telluride of niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, cobalt, manganese, iron, nickel, or a transition metal; (d) boron nitride, or (e) a combination thereof; wherein the disc, platelet or sheet has a thickness of less than 100 nm.

In some embodiments, the cathode active material in the lithium metal battery is an organic material or a polymeric material selected from the group consisting of: poly (anthraquinone thioether) (PAQS), lithium oxycarbide, 3,4,9, 10-perylene tetracarboxylic dianhydride (PTCDA), poly (anthraquinone thioether), pyrene-4, 5,9, 10-tetraketone (PYT), polymer-bonded PYT, quinone (triazene), redox-active organic material, tetracyanoquinodimethane (TCNQ), tetracyanoethylene (TCNE), 2,3,6,7,10, 11-Hexamethoxytriphenylene (HMTP), poly (5-amino-1, 4-dihydroxyanthraquinone) (PADAQ), phosphazene disulfide polymer ([ (NPS) ₂ ) ₃ ]n), lithiated 1,4,5, 8-naphthalene tetralin formaldehyde polymers, hexaazabinaphthyl (HATN), hexaazatriphenylene hexanitrile (HAT (CN) ₆ ) 5-benzylidenyl hydantoin, isatin lithium salt, pyromellitic diimide lithium salt, tetrahydroxy-p-benzoquinone derivative (THQLi) ₄ ) N, N ' -diphenyl-2, 3,5, 6-tetratone piperazine (PHP), N ' -diallyl-2, 3,5, 6-tetratone piperazine (AP), N ' -dipropyl-2, 3,5, 6-tetratone piperazine (PRP), thioether polymers, quinone compounds, 1, 4-benzoquinone, 5,7,12,14-Pentacene Tetratone (PT), 5-amino-2, 3-dihydro-1, 4-dihydroxyanthraquinone (ADDAQ), 5-amino-1, 4-dihydroxyanthraquinone (ADAQ), quinine calixarene (calixquinone), li ₄ C ₆ O ₆ 、Li ₂ C ₆ O ₆ 、Li ₆ C ₆ O ₆ Or a combination thereof.

The thioether polymer is selected from poly [ methane trinitrotoluene-tetra (thiomethylene) ] (PMTTM), poly (2, 4-dithiopentene) (PDTP), a polymer comprising poly (ethylene-1, 2-tetrathiol) (PETT) as a backbone thioether polymer, a side chain thioether polymer having a backbone consisting of conjugated aromatic moieties and having thioether side chains as side chains, poly (2-phenyl-1, 3-dithiolane) (PPDT), poly (1, 4-bis (1, 3-dithiolane-2-yl) benzene) (PDDTB), poly (tetrahydrobenzodithiophene) (PTHBDT), poly [1,2,4, 5-tetrakis (propylthio) benzene ] (PTKPTB), or poly [3,4 (ethylenedithio) thiophene ] (PETT).

In a preferred embodiment, the cathode active material is an organic material containing a phthalocyanine compound selected from the group consisting of: copper phthalocyanine, zinc phthalocyanine, tin phthalocyanine, iron phthalocyanine, lead phthalocyanine, nickel phthalocyanine, vanadyl phthalocyanine, chromium fluoride phthalocyanine, magnesium phthalocyanine, manganese phthalocyanine, dilithium phthalocyanine, aluminum phthalocyanine chloride, cadmium phthalocyanine, gallium phthalocyanine chloride, cobalt phthalocyanine, silver phthalocyanine, metal-free phthalocyanine, chemical derivatives thereof, or combinations thereof.

In the lithium metal battery, the cathode active material is more than 30mg/cm ² (preferably greater than 40 mg/cm) ² More preferably greater than 45mg/cm ² And most preferably greater than 50mg/cm ² ) And/or wherein the first conductive foam structure has a thickness of not less than 300 μm (preferably not less than 400 μm, more preferably not less than 500 μm, and may be greater than 600 μm).

Drawings

Fig. 1 (a) is a schematic diagram of a prior art lithium ion battery cell consisting of an anode current collector, one or two layers of anode active material (e.g., thin Si coating) coated on both major surfaces of the anode current collector, a porous separator and electrolyte, one or two layers of cathode electrode (e.g., sulfur layer), and a cathode current collector;

FIG. 1 (B) is a schematic diagram of a prior art lithium ion battery in which the electrode layer is composed of an active material (e.g., graphite or tin oxide particles in the anode layer or LiCoO in the cathode layer ₂ ) Is composed of discrete particles of a conductive additive (not shown), and a resin binder (not shown).

Fig. 1 (C) is a schematic diagram of a lithium ion battery cell of the present invention comprising a quasi-solid anode (composed of anode active material particles and conductive filaments directly mixed or dispersed in an electrolyte), a porous separator, and a quasi-solid cathode (composed of cathode active material particles and conductive filaments directly mixed or dispersed in an electrolyte). In this embodiment, no resin binder is required.

Fig. 1 (D) is a schematic diagram of a lithium metal battery cell of the present invention comprising an anode (containing a lithium metal layer deposited on the surface of a Cu foil), a porous separator, and a quasi-solid cathode (composed of cathode active material particles and conductive filaments directly mixed or dispersed in an electrolyte). In this embodiment, no resin binder is required.

FIG. 2 (A) vapor pressure ratio data (p) as a function of sodium salt molecular ratio x (NaTFSI/DOL) _s P=vapor pressure of solution/vapor pressure of solvent alone) based on theoretical predictions of classical Raoult's Law.

FIG. 2 (B) vapor pressure ratio data (p) as a function of sodium salt molecular ratio x (NaTFSI/DME) _s P=vapor pressure of solution/vapor pressure of solvent alone), based on theoretical predictions of classical raoult's law.

FIG. 2 (C) molecular ratio x (NaPF) as sodium salt ₆ Vapor pressure ratio data (p) as a function of/DOL _s P=vapor pressure of solution/vapor pressure of solvent alone), based on theoretical predictions of classical raoult's law.

FIG. 2 (D) molecular ratio x (NaTFSI/DOL, naTFSI/DME, naPF) as sodium salt ₆ Vapor pressure ratio data (p) as a function of/DOL _s P=vapor pressure of solution/vapor pressure of solvent alone), based on theoretical predictions of classical raoult's law.

FIG. 3 (A) is a schematic diagram of a close-packed highly ordered structure of a solid electrolyte;

FIG. 3 (B) has a cation (e.g., na ⁺ ) A schematic of a fully amorphous liquid electrolyte that can readily migrate through a large free volume portion;

fig. 3 (C) has a random or amorphous structure of a quasi-solid electrolyte that separates salt species to create solvent molecules of an amorphous region that allows free (non-clustered) cations to migrate easily.

FIG. 4 (A) Na of electrolyte (e.g., naTFSI salt/(DOL+DME) solvent) in relation to sodium salt molecular ratio x ⁺ Ion transfer number.

FIG. 4 (B) Na of electrolyte (e.g., naTFSI salt/(EMImTFSI+DOL solvent)) in relation to sodium salt molecular ratio x ⁺ Ion transfer number.

FIG. 4 (C) Na of electrolyte (e.g., naTFSI salt/(EMImTFSI+DME) solvent) in relation to sodium salt molecular ratio x ⁺ Ion transfer number.

FIG. 4 (D) Na in various electrolytes (as in FIGS. 6 to 8) correlated with sodium salt molecular ratio x ⁺ Ion transfer number.

Fig. 5 is a schematic illustration of a common process for producing expanded graphite, expanded graphite flakes (thickness >100 nm) and graphene flakes (thickness <100nm, more typically <10nm, and can be as thin as 0.34 nm).

Fig. 6 (a) plots the conductivity (percolation behavior) of conductive filaments in a quasi-solid electrode as a function of the volume fraction of conductive filaments (carbon nanofibers).

Fig. 6 (B) plots the conductivity (percolation behavior) of conductive filaments in a quasi-solid electrode as a function of the volume fraction of conductive filaments (reduced graphene oxide sheets).

Fig. 7 is a largong 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 4 data curves are for cells prepared according to the examples of the present invention, while the remaining one is a cell prepared by conventional electrode paste coating (roll coating).

FIG. 8 Lagong plots (weight power density versus weight energy density) for three cells each containing graphene-surrounded Si nanoparticles as anode active material and LiCoO ₂ The nanoparticles serve as cathode active materials. Experimental data are from Li-ion battery cells prepared by the method of the invention (following the sequences S1 and S3) and Li-ion battery cells prepared by conventional electrode paste coatingObtained.

FIG. 9 contains lithium foil as the anode active material, dilithium rhodia (Li) ₂ C ₆ O ₆ ) As cathode active material and lithium salt (LiPF ₆ ) PC/DEC as Lagong plot for lithium metal batteries of organic electrolyte. The data are lithium metal cells prepared by the method of the invention (with sequences of 2 different salt concentrations S2 and S3) and lithium metal cells prepared by conventional electrode paste coating.

Fig. 10 is a Lagong plot of two sodium ion capacitors, each containing pre-sodified hard carbon particles as the anode active material and graphene sheets as the cathode active material; one cell has an anode prepared by a conventional slurry coating process and the other cell has a quasi-solid anode prepared according to the method of the present invention.

Detailed Description

The present invention is directed to a method of producing a lithium or sodium battery that exhibits an abnormally high volumetric energy density that has not been previously achieved. The battery may be a primary battery, but is preferably a secondary battery selected from a lithium ion battery, a lithium metal secondary battery (e.g., using lithium metal as an anode active material), a sodium ion battery, a sodium metal battery, a lithium ion capacitor, or a sodium ion capacitor. Batteries are based on aqueous electrolytes, nonaqueous or organic electrolytes, ionic liquid electrolytes, or mixtures of organic liquids and ions. Preferably, the electrolyte is a "quasi-solid electrolyte" containing a high concentration of lithium or sodium salt in a liquid solvent to the extent that: it behaves like a solid but is deformable even when the desired amounts of conductive filaments and active materials are added to the electrolyte (hence the term "deformable quasi-solid electrode material"). The shape of the lithium battery may be cylindrical, square, button-like, etc. The present invention is not limited to any cell shape or configuration.

For convenience, the materials selected will be used, such as lithium iron phosphate (LFP), vanadium oxide (V _x O _y ) Dilithium rhodizonate (Li) ₂ C ₆ O ₆ ) And copper phthalocyanine (CuPc) as illustrative examples of cathode active materialsAnd graphite, hard carbon, snO, co ₃ O ₄ And Si particles as examples of anode active materials. These should not be construed as limiting the scope of the invention.

As shown in fig. 1 (a), a prior art lithium battery cell is typically composed of an anode current collector (e.g., a Cu foil), an anode electrode or anode active material layer (e.g., a Li metal foil or a pre-lithiated Si coating deposited on one or both sides of the Cu foil), a porous separator and/or electrolyte composition, a cathode electrode or cathode active material layer (or two cathode active material layers coated on both sides of the Al foil), and a cathode current collector (e.g., an Al foil).

In a more commonly used prior art cell configuration (fig. 1 (B)), the anode layer is composed of anode active material (e.g., graphite, hard carbon, or Si) particles, conductive additives (e.g., carbon black particles), and a resin binder (e.g., SBR or PVDF). The cathode layer is composed of cathode active material particles (e.g., LFP particles), conductive additives (e.g., carbon black particles), and a resin binder (e.g., PVDF). Both the anode layer and the cathode layer are typically up to 100-200 μm thick to produce approximately sufficient current flow per unit electrode area. This thickness range is considered an industry accepted constraint in which battery designers typically operate. This thickness constraint is due to several reasons: (a) Existing battery electrode coating machines are not equipped for coating an excessively thin or thick electrode layer; (b) Thinner layers are preferred based on consideration of reduced lithium ion diffusion path length; but too thin (e.g., <100 μm) layers do not contain a sufficient amount of active lithium storage material (hence, insufficient current output); (c) Thicker electrodes tend to delaminate or crack when dried or handled after roll coating; and (d) all inactive material layers (e.g., current collectors and separators) in the battery cells must be kept to a minimum in order to obtain a minimum non-contributing weight and a maximum lithium storage capacity, and thus a maximum energy density (Wk/kg or Wh/L of the cell).

In a less common cell configuration, as shown in fig. 1 (a), an anode active material (e.g., si coating) or a cathode active material (e.g., lithium transition metal oxide) is deposited directly on a current collector such as a copper foil or an Al foil in the form of a thin film. However, such thin film structures with extremely small thickness direction dimensions (typically much less than 500nm, often having to be thinner than 100 nm) mean that only small amounts of active material can be incorporated into the electrode (given the same electrode or current collector surface area), providing low total lithium storage capacity and low lithium storage capacity per unit electrode surface area. Such a thin film must have a thickness of less than 100nm to be more resistant to cycle-induced cracking (for the anode) or to facilitate the full use of the cathode active material. This constraint further reduces the total lithium storage capacity and 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 100nm have been found to exhibit poor crack resistance during battery charge/discharge cycles. The Si layer is fragmented only a few cycles. On the cathode side, a sputtered layer of lithium metal oxide thicker than 100nm cannot allow lithium ions to sufficiently penetrate and reach the whole of the cathode layer, resulting in poor cathode active material utilization. The desired electrode thickness is at least 100 μm, with individual active material coatings or particles having a size desirably less than 100 nm. Thus, these thin film electrodes deposited directly on the current collector (where the thickness <100 nm) are three (3) orders of magnitude lower than the required thickness. As a further problem, all cathode active materials are not capable of conducting both electrons and lithium ions. A large layer thickness means an excessively high internal resistance and poor active material utilization. Sodium batteries have similar problems.

In other words, there are several conflicting factors that must be considered simultaneously when designing and selecting with respect to the cathode or anode active material in terms of material type, size, electrode layer thickness, and active material mass loading. To date, any prior art teachings have not provided an effective solution to these often conflicting problems. We have solved these challenging problems that have plagued battery designers and electrochemistry for over 30 years by developing new methods of producing lithium or sodium batteries as disclosed herein.

The lithium battery cells of the prior art are typically made by a process comprising the steps of: (a) The first step is to mix particles of an anode active material (e.g., si nanoparticles or mesophase carbon microbeads, MCMB), a conductive filler (e.g., graphite flake), a resin binder (e.g., PVDF) in a solvent (e.g., NMP) to form an anode slurry. On a separate basis, cathode active material particles (e.g., LFP particles), conductive filler (e.g., acetylene black), resin binder (e.g., PVDF) are mixed and dispersed in a solvent (e.g., NMP) to form a cathode slurry. (b) The second step includes coating an anode slurry onto one or both major surfaces of an anode current collector (e.g., cu foil), and drying the coated layer by evaporating a solvent (e.g., NMP) to form a dried anode electrode coated on the Cu foil. Similarly, the cathode slurry is coated and dried to form a dried cathode electrode coated on an Al foil. Slurry coating is typically performed in roll-to-roll fashion under actual manufacturing conditions; (c) The third step includes laminating the anode/Cu foil, porous separator layer and cathode/Al foil together to form a 3-layer or 5-layer assembly, cutting and slitting the assembly to the desired dimensions and stacking to form a rectangular structure (as an example of a shape) or winding into a cylindrical cell structure. (d) The rectangular or cylindrical laminate structure is then enclosed in an aluminum plastic laminate envelope or steel shell. (e) A liquid electrolyte is then injected into the laminate structure to produce a lithium battery cell.

There are several serious problems associated with this approach and the resulting lithium battery cells:

1) It is very difficult to produce an electrode layer (anode layer or cathode layer) thicker than 200 μm. There are several reasons for this to occur. Electrodes of 100-200 μm thickness typically require heating zones of 30-50 meters in length in a slurry coating facility, which is too time consuming, too energy consuming, and not cost effective. For some electrode active materials, such as metal oxide particles, it is not possible to produce electrodes of good structural integrity thicker than 100 μm on a continuous basis in a practical manufacturing environment. The resulting electrode is very fragile and brittle. Thicker electrodes have a high tendency to delaminate and crack.

2) With conventional methods, as depicted in FIG. 1 (A), the actual mass loading of the electrode and the apparent density of the active material are too low to achieve>Weight energy of 200Wh/kgBulk density. In most cases, the anode active material mass loading (areal density) of the electrode is significantly less than 25mg/cm ² And even for relatively large graphite particles, the apparent bulk or tap density of the active material is typically less than 1.2g/cm ³ . The cathode active material mass loading (areal density) of the electrode is significantly less than 45mg/cm for lithium metal oxide inorganic materials ² And less than 15mg/cm for organic or polymeric materials ² . In addition, there are so many other inactive materials (e.g., conductive additives and resin binders) that additional weight and volume of the electrode are added without contributing to the cell capacity. These low areal and low bulk densities result in relatively low gravimetric and volumetric energy densities.

3) The conventional method requires dispersing electrode active materials (anode active material and cathode active material) in a liquid solvent (for example, NMP) to manufacture a slurry, and when coated on the surface of a current collector, the liquid solvent must be removed to dry the electrode layer. Once the anode and cathode layers are laminated together with the separator layer and encapsulated in a housing to make the supercapacitor cell, a liquid electrolyte is then injected into the cell. In practice, the two electrodes are wetted, then the electrodes are dried, and finally they are wetted again. This wet-dry-wet process does not sound like a good process at all.

4) Current lithium ion batteries still suffer from relatively low gravimetric energy densities and relatively low volumetric energy densities. Commercially available lithium ion batteries exhibit a gravimetric energy density of about 150-220Wh/kg and a volumetric energy density of 450-600 Wh/L.

In the literature, energy density data reported based on active material weight alone or electrode weight cannot be directly converted to the energy density of the actual battery cell or device. The "non-contributing weight" or weight of other device components (binders, conductive additives, current collectors, separators, electrolytes, and encapsulants) must also be taken into account. Conventional production methods result in anode active materials (e.g., graphite or carbon) in lithium ion batteries typically in a weight proportion of from 12% to 17%, and cathode activeSexual materials (e.g. LiMn ₂ O ₄ ) The weight proportion of (2) is from 20% to 35%.

The present invention provides a method of producing lithium or sodium battery cells having high electrode thickness, high active material mass loading, low non-contributing weight and volume, high capacity, and high energy density.

In certain embodiments, the method comprises:

(a) Combining an amount of active material (anode active material or cathode active material), an amount of electrolyte, and a conductive additive to form a deformable and conductive electrode material, wherein the conductive additive comprising conductive filaments forms a 3D network of electron conduction pathways; ( These conductive filaments, such as carbon nanotubes and graphene sheets, are a large number of randomly aggregated filaments prior to mixing with the particles of active material and electrolyte. The mixing procedure involves dispersing these conductive filaments in a highly viscous electrolyte containing particles of active material. This will be discussed further in the following sections. )

(b) Forming the electrode material into a quasi-solid electrode, wherein the forming step includes deforming the electrode material into an electrode shape without interrupting a 3D network of the electron conduction paths, thereby maintaining the electrode at not less than 10 ^- ⁶ S/cm (preferably not less than 10) ^-5 S/cm, more preferably not less than 10 ^-4 S/cm, further preferably not less than 10 ^-3 S/cm, still more preferably and typically not less than 10 ^-2 S/cm, even more typically and preferably not less than 10 ^-1 Conductivity of S/cm, and even more typically and preferably not less than 1S/cm; up to 300S/cm was observed);

(c) Forming a second electrode (the second electrode may be a quasi-solid electrode or a conventional electrode); and is also provided with

(d) An alkali metal cell is formed by combining the quasi-solid electrode and the second electrode, the alkali metal cell having an ion-conducting membrane disposed between the two electrodes.

As shown in fig. 1 (C), one preferred embodiment of the present invention is an alkali metal ion cell having a conductive quasi-solid anode 236, a conductive quasi-solid cathode 238, and a porous membrane 240 (or ion permeable membrane) that electronically separates the anode and cathode. These three components are typically enclosed in a protective housing (not shown) that typically has an anode tab (terminal) connected to the anode and a cathode tab (terminal) connected to the cathode. These tabs are used to connect to an external load (e.g., a battery-powered electronic device). In this particular embodiment, quasi-solid anode 236 contains an anode active material (e.g., si particles, not shown in fig. 1 (C)), an electrolyte phase (typically containing lithium or sodium salts dissolved in a solvent; also not shown in fig. 1 (C)), and a conductive additive (containing conductive filaments) that forms a 3D network 244 of electron conducting pathways. Similarly, the quasi-solid cathode contains a cathode active material, an electrolyte, and a conductive additive (containing conductive filaments) that forms a 3D network 242 of electron conducting pathways.

As shown in fig. 1 (D), another preferred embodiment of the present invention is an alkali metal cell having an anode comprised of a lithium or sodium metal coating/foil 282 deposited/attached to a current collector 280 (e.g., cu foil), a quasi-solid cathode 284, and a separator or ion conducting membrane 282. The quasi-solid cathode 284 contains a cathode active material 272 (e.g., liCoO) ₂ An electrolyte phase 274 (typically containing lithium or sodium salts dissolved in a solvent), and a conductive additive phase (containing conductive filaments) forming a 3D network 270 of electron conducting pathways. The invention also includes lithium ion capacitors and sodium ion capacitors.

The electrolyte is preferably a quasi-solid electrolyte containing a lithium salt or sodium salt dissolved in a liquid solvent, the salt concentration of which is not less than 2.5M, preferably more than 3M, more preferably more than 3.5M, still more preferably more than 5M, still more preferably more than 7M, and even more preferably more than 10M. In certain embodiments, the electrolyte is a quasi-solid electrolyte containing a lithium or sodium salt dissolved in a liquid solvent, having a salt concentration of from 3.0M to 14M. The choice of lithium or sodium salt and liquid solvent is discussed further in the following sections.

Both the quasi-solid anode and the quasi-solid cathode preferably have a thickness of more than 200 μm (preferably more than 300 μm, more preferably more than 400 μm, still more preferably Greater than 500 μm, still more preferably greater than 800 μm, still more preferably greater than 1mm, and may be greater than 5mm, 1cm, or thicker. There is no theoretical limit to the thickness of the electrode of the present invention. In the cell of the present invention, the anode active material typically constitutes not less than 20mg/cm in the anode ² (more typically and preferably not less than 25 mg/cm) ² And more preferably not less than 30mg/cm ² ) Is used for the electrode active material loading. For inorganic materials as cathode active materials, the cathode active materials constitute not less than 45mg/cm ² (typically and preferably greater than 50 mg/cm) ² And more preferably greater than 60mg/cm ² ) Is not less than 25mg/cm for organic or polymeric cathode active materials ² )。

In such a configuration (fig. 1 (C) to 1 (D)) the electrons need only travel a short distance (e.g. a few microns) before they are collected by the conductive filaments that constitute the 3D network of electron conduction paths and that are present everywhere in the whole quasi-solid electrode (anode or cathode). In addition, all electrode active material particles are pre-dispersed in the liquid electrolyte (no wettability problem), eliminating the presence of a dry pouch typically present in electrodes prepared by conventional methods of wet coating, drying, packaging and electrolyte injection. Thus, the process or method of the present invention has a completely unexpected advantage over conventional battery cell production methods.

These conductive filaments (e.g., carbon nanotubes and graphene sheets) as supplied are initially a large number of randomly aggregated filaments before mixing with the particles of active material and electrolyte. The mixing procedure involves dispersing these conductive filaments in a highly viscous electrolyte containing particles of active material. This is not a trivial task as one might consider. The dispersion of nanomaterials (particularly nanofilament materials such as carbon nanotubes, carbon nanofibers, and graphene sheets) in highly flowable (non-tacky) liquids has been known to be difficult, not to mention in highly tacky quasi-solids such as electrolytes containing high loadings of active materials (e.g., solid particles such as Si nanoparticles for anodes and lithium cobalt oxide for cathodes). In some preferred embodiments, this problem is further exacerbated by the following: the electrolyte itself is a quasi-solid electrolyte containing a high concentration of lithium or sodium salt in a solvent.

In some preferred embodiments, the electrolyte contains an alkali metal salt (lithium salt and/or sodium salt) dissolved in an organic or ionic liquid solvent, wherein the alkali metal salt molecular ratio is sufficiently high such that the electrolyte exhibits a vapor pressure (when measured at 20 ℃) of less than 0.01kPa or less than 0.6 (60%) of the vapor pressure of the solvent alone, a flash point at least 20 degrees celsius higher than the flash point of the first organic liquid solvent alone (when no lithium salt is present), a flash point above 150 ℃, or no detectable flash point at all.

Most surprising and of great scientific and technical importance is our following findings: the flammability of any volatile organic solvent can be effectively suppressed provided that a sufficiently high amount of alkali metal salt is added to and dissolved in the organic solvent to form a solid-like or quasi-solid electrolyte. Generally, such quasi-solid electrolytes exhibit less than 0.01kPa and often less than 0.001kPa

(when measured at 20 ℃) and less than 0.1kPa and often less than 0.01kPa (when measured at 100 ℃). In many cases, the vapor pressure of the corresponding pure solvent in which any alkali metal salt is not dissolved is typically significantly higher, vapor molecules are in fact too few to detect.

Very important observations are: the high solubility of alkali metal salts in otherwise highly volatile solvents (the large molecular ratio or mole fraction of alkali metal salts, typically >0.2, more typically >0.3, and often >0.4 or even > 0.5) can significantly reduce the amount of volatile solvent molecules that can escape into the vapor phase under thermodynamic equilibrium conditions. In many cases, this effectively prevents flammable solvent gas molecules from initiating a flame even at extremely high temperatures (e.g., using a torch). The flash point of a quasi-solid electrolyte is typically at least 20 degrees (often >50 or >100 degrees) higher than the flash point of a pure organic solvent alone. In most cases, the flash point is above 150 ℃ or no flash point can be detected. The electrolyte will not ignite. Furthermore, any accidentally initiated flame does not last longer than a few seconds. This is a very important finding in view of the insight that fire and explosion concerns have been a major obstacle to the widespread acceptance of battery powered electric vehicles. The new technology can help to speed up the rise of the EV industry that is full of life.

From a fundamental chemical principle perspective, adding solute molecules to a liquid increases the boiling temperature of the liquid and reduces its vapor pressure and freezing temperature. These phenomena, as well as osmosis, depend only on the solute concentration and not on its type, and are known as the collisional nature of the solution. The initial raoult's law provides the vapor pressure of the solution (p _s ) Relationship between the ratio of vapor pressure (p) to pure liquid and mole fraction (x) of solute:

p _s /p＝e ^-x equation (1 a)

For dilute solutions, x<<1, and thus e ^-x And 1-x. Thus, for species with low solute mole fractions, a more common form of raoult's law is obtained:

p _s p=1-x equation (1 b)

To determine whether classical raoult's law can be used to predict the vapor pressure of highly concentrated electrolytes, we continue to study a wide variety of alkali metal salt/organic solvent combinations. Some examples of our findings are summarized in fig. 2 (a) to 2 (D), where experiment p is performed for several salt/solvent combinations _s The value of/p is plotted as a function of the molecular ratio (mole fraction, x). A curve based on classical raoult's law, equation (1 a), is also plotted for comparison purposes. Obviously, p for all types of electrolytes _s The value of/p conforms to the Raoult's law prediction until the mole fraction x reaches about 0.2, beyond which the vapor pressure drops rapidly to essentially zero (barely detectable). When the vapor pressure is below the threshold, no flame will be initiated and the present invention provides an excellent platform material chemistry that effectively inhibits flame initiation.

Although it is not uncommon for deviations scientifically from Raoult's law, this type of p has never been observed for any binary solution system _s A/p curve. In particular, for safety reasons,no report has been made on ultra-high concentration battery electrolytes (having a high molecular fraction, for example>0.2 or>0.3) of an alkali metal salt). This is indeed unexpected and of great technical and scientific significance.

We have further unexpectedly found that: the presence of a 3D network of electron conducting pathways made up of conductive filaments serves to further reduce the threshold concentration of alkali metal salt required for critical vapor pressure suppression.

Another unexpected element of the present invention is the following: we can dissolve high concentrations of alkali metal salts in nearly every type of common battery grade organic solvent to form a quasi-solid electrolyte suitable for use in rechargeable alkali metal batteries. Expressed in more readily identifiable terms, the concentration is typically greater than 2.5M (moles/liter), more typically and preferably greater than 3.5M, still more typically and preferably greater than 5M, still more preferably greater than 7M, and most preferably greater than 10M. In the case of a salt concentration of not less than 2.5M, the electrolyte is no longer a liquid electrolyte; instead, it is a quasi-solid electrolyte. In the field of lithium or sodium batteries, such high concentrations of alkali metal salts in solvents are generally considered to be impossible and undesirable. However, we have found that these quasi-solid electrolytes are surprisingly good electrolytes for both lithium and sodium batteries in terms of significantly improved safety (non-flammability), improved energy density and improved power density.

In general, the vapor pressure of a solution cannot be predicted directly and straightforwardly from the concentration value in M (moles/liter). Instead, for alkali metal salts, the molecular ratio x in Raoult's law is the sum of the mole fractions of positive and negative ions, which are proportional to the degree of dissociation of the metal salt in a particular solvent at a given temperature. The molar/liter concentration does not provide enough information to predict vapor pressure.

In general, it is not possible to achieve such high concentrations of alkali metal salts (e.g., x=0.3-0.7) in the organic solvents used in the battery electrolyte, especially when the conductive filaments and/or active material particles forming the network are also present. Through extensive and intensive studies, we further found that: if first (a) a highly volatile co-solvent is used to increase the amount of alkali metal salt dissolved in the solvent mixture, and then (b) once the dissolution procedure is completed, partial or complete removal of the volatile co-solvent can significantly increase the apparent solubility of the alkali metal salt in the particular solvent. Quite unexpectedly, even though the solution will be in a highly supersaturated state, removal of the co-solvent typically does not result in precipitation or crystallization of the alkali metal salt from the solution. This novel and unique method appears to produce a material state in which most solvent molecules are trapped or held in place by non-volatile alkali metal salt ions (in fact, lithium/sodium salts are solid-like). Thus, very few volatile solvent molecules can escape into the vapor phase, and thus, there are very few "flammable" gas molecules to help initiate or sustain a flame. In the prior art of Na, K or Li metal batteries, this is not technically proposed to be possible or viable.

Furthermore, those skilled in the chemical or material science arts will expect that such high salt concentrations should cause the electrolyte to behave like a solid with extremely high viscosity, and therefore, the electrolyte should not be suitable for rapid diffusion of alkali metal ions therein. Thus, those skilled in the art will expect that an alkali metal cell containing such a solid-like electrolyte will not and cannot exhibit high capacity (i.e., the cell should have poor rate performance) at high charge-discharge rates or under high current density conditions. Contrary to these expectations of the person skilled in the art or even of the excellent one, all alkali metal cells containing such quasi-solid electrolytes are given a high energy density and a high power density, thus achieving a long cycle life. It appears that the quasi-solid electrolyte as invented and disclosed herein facilitates easy alkali metal ion transport. This unexpected finding may be due to two main factors: one is related to the internal structure of the electrolyte and the other is related to high Na ⁺ Or Li (lithium) ⁺ Ion Transfer Number (TN), which will be further described in the later sections of the specification.

Without wishing to be bound by theory, it is possible to The internal structure of three fundamentally different types of electrolytes is visualized with reference to fig. 3 (a) to 3 (C). Fig. 3 (a) schematically shows a close-packed highly ordered structure of a typical solid electrolyte, in which almost no free volume is used for diffusion of alkali metal ions. Migration of any ions in this crystal structure is very difficult, resulting in a very low diffusion coefficient (10 ^-16 To 10 ^-12 cm ² S) and extremely low ionic conductivity (typically from 10 ^-7 S/cm

To 10 ^-4 S/cm). In contrast, as schematically shown in fig. 3 (B), the internal structure of the liquid electrolyte is completely amorphous, having cations (e.g., or Li ⁺ Or Na (or) ⁺ ) A large free volume fraction that can easily migrate through, resulting in a high diffusion coefficient (10 ^-8 To 10 ^-6 cm ² S) and high ionic conductivity (typically from 10 ^-3 S/cm to 10 ^-2 S/cm). However, liquid electrolytes containing low concentrations of alkali metal salts are also flammable and prone to dendrite formation, thereby creating a fire and explosion hazard. Shown schematically in fig. 3 (C) is the random or amorphous structure of a quasi-solid electrolyte having solvent molecules that separate salt species to create an amorphous region that allows free (non-clustered) cations to migrate readily. This structure is suitable for achieving high ionic conductivity values (typically 10 ^-4 S/cm to 8x10 ^-3 S/cm), but remain nonflammable. There are relatively few solvent molecules and these molecules are held (prevented from evaporating) by overwhelmingly large amounts of salt species and the network of conductive filaments.

As a second factor, we have found that quasi-solid electrolytes provide TN greater than 0.3 (typically in the range from 0.4 to 0.8), while all lower concentration electrolytes used in all current Li ion and Na ion cells (e.g.)<2.0M; typical values in most cases 1M) are 0.1-0.2. As indicated in fig. 4 (a) to 4 (D), na in the low salt concentration electrolyte ⁺ The ion transfer number decreases with increasing concentration from x=0 to x=0.2-0.35. However, above the molecular ratio of x=0.2-0.35, the number of transitions increases with increasing salt concentration, indicating Na ⁺ Or Li (lithium) ⁺ Radical changes in ion transport mechanisms. Also, without wishing to be bound by theory, we want to use Na ⁺ The ions as examples provide the following scientifically reasonable explanation (similar explanation applies to Li ⁺ Ion): when Na is ⁺ Ion in low salt concentration electrolyte (e.g., x<0.2 During travel, each Na ⁺ The ion drags one or more solvated molecules therewith. Such co-migration of clusters of charged species may be further hindered if the fluid viscosity increases (i.e., when more salt is added to the solvent).

Fortunately, when ultra-high concentrations of Na salts are present (e.g., having x>0.3 Na) of the composition ⁺ The number of ions may greatly exceed the number of available solvating species or solvent molecules that might otherwise cluster lithium ions, thereby forming multi-member complex species and slowing Na ⁺ And ion diffusion process. The high Na ⁺ The ion concentration makes it possible to have more "free Na ⁺ Ions "(those acting alone without clustering) to provide high Na ⁺ Number of transitions (thus providing easy Na) ⁺ Transmission). In other words, the sodium ion transport mechanism changes from a multi-ion complex dominant mechanism (with a large hydrodynamic radius) to having a large amount of available free Na ⁺ Single ion dominant mechanisms of ions (with smaller hydrodynamic radii). The observation further confirms that Na ⁺ Ions can work on the quasi-solid electrolyte without compromising the rate capability of the Na metal cell. However, these highly concentrated electrolytes are nonflammable and safe. In any of the previous reports, these integrated features and advantages for battery applications have never been taught or even slightly suggested. The theoretical aspects of the ion transfer number of a quasi-solid electrolyte are now described below:

The ionic conductivity of lithium or sodium ions is an important factor to consider when selecting an electrolyte system for a battery. Na (Na) ⁺ The ionic conductivity of the ions in the organic liquid-based electrolyte is about 10 ^-3 -10 ^-2 S/cm and the ionic conductivity in solid state electrolytes is typically from 10 ^-7 -10 ^-4 S/cm. Solid state electrolytes have not been used to any significant extent in any battery systems due to the low ionic conductivity. This is unfortunately due to the inability of solid state electrolytes to resist dendrite penetration in alkali metal secondary batteries. In contrast, our quasi-solid electrolyte typically has an ionic conductivity of from 10 ^-4 -8x 10 ^-3 S/cm, is sufficient for use in rechargeable batteries.

Ion mobility or diffusion coefficient is not the only important transport parameter for the battery electrolyte. The number of individual transfers of cations and anions is also important. For example, when a viscous liquid is used as an electrolyte in an alkali metal cell, the ion mobility decreases. Therefore, in order to achieve high ion conductivity, a high transfer number of alkali metal ions in the electrolyte is required.

Only one type of cation (i.e., na) can be studied by alternating current impedance spectroscopy and pulsed field gradient NMR techniques ⁺ ) And one type of anion, plus ionic transport and diffusion in a liquid electrolyte composed of a liquid solvent or a mixture of two liquid solvents. The alternating impedance provides information about the total ionic conductivity and NMR allows the individual self-diffusion coefficients of cations and anions to be determined. Generally, the self-diffusion coefficient of cations is slightly higher than that of anions. It has been found that Haven ratios obtained from the diffusion coefficient and the total ion conductivity typically range from 1.3 to 2, indicating ion pairs or ion complexes (e.g. Na ⁺ Clusters of solvated molecules) are important features in electrolytes containing low salt concentrations.

When two different alkali metal salts or one ionic liquid (as alkali metal salts or as liquid solvents) are added to the electrolyte, the situation becomes more complicated, resulting in a solution with at least 3 or 4 types of ions. In this case, for example, it is advantageous to use alkali metal salts containing the same anions as in solvated ionic liquids, since the amount of soluble alkali metal salt is higher than in mixtures with different anions. Thus, the next logical question to be asked is whether it is possible to dissolve more sodium (or lithium) salt in the liquid solvent To improve Na ⁺ (or Li) ⁺ ) Number of transfers.

Total ionic conductivity sigma of a tri-ionic liquid mixture _dc The relationship with the individual diffusion coefficient Di of the ion can be given by the Nernst-Einstein (Nernst-Einstein) equation: sigma (sigma) _dc ＝(e ² /k _B TH _R )[(N _Na ⁺ )(D _Na ⁺ )+(N _E ⁺ )(D _E ⁺ )+(N _B ^- )(D _B ^- )]Equation (2)

Here, e and k _B Indicating the meta-charge and the Boltzmann constant, respectively, and N _i Is a single ion (Na ⁺ 、Li ⁺ 、ClO ₄ ^- Etc.). Haven ratio H _R The cross-correlation between the different types of ion movement is explained.

Simple ionic liquids having only one type of cation and anion are characterized by Haven ratios typically ranging from 1.3 to 2.0. A Haven ratio of greater than 1 indicates that ions of different charges preferentially move in the same direction (i.e., ions are transported in pairs or clusters). The raman spectra of various electrolytes can be used to find evidence of such ion pairs. The Haven ratio in the tri-ionic mixture has a value in the range from 1.6 to 2.0. Compared with the electrolyte with x=0, H _R Slightly higher values indicate more significant pair formation in the mixture.

For the same mixture, the total ionic conductivity of the mixture decreases with increasing alkali metal salt content x. This conductivity drop is directly related to the drop in the individual self-diffusion coefficients of all ions. Our studies on different mixtures of ionic liquids with alkali metal salts show that the viscosity increases with increasing salt content x. These findings indicate that the addition of alkali metal salts results in stronger ionic bonds in the liquid mixture, which slow down the hydrodynamics. This may be due to the fact that the coulombic interaction between small sodium (or lithium) ions and anions is stronger than between larger organic cations and anions. Therefore, the decrease in ion conductivity with an increase in alkali metal salt content x is not due to a decrease in the number density of mobile ions, but due to a decrease in the mobility of ions.

In order to analyze the individual contributions of cations and anions to the total ionic conductivity of the mixture, the apparent transfer number t can be defined by _i ：

t _i ＝ N _i Di/(ΣN _i Di) equation (3)

For example, in a mixture of N-butyl-N-methyl-pyrrolidinium bis (trifluoromethanesulfonyl) imide (BMP-TFSI) and sodium bis (trifluoromethanesulfonyl) imide (Na-TFSI) (containing Na) ⁺ 、BMP ⁺ And TFSI ^- Ion), apparent lithium transfer number t _Li Increases with increasing Na-TFSI content; at x=0.34, t _Na =0.242 (comparative x<T at 0.2 _Na <0.1)，D _Na ≈0.7D _TFSI And D _BMP ≈1.6D _TFSI . Apparent Na in the mixture ⁺ The main reason for the higher number of transitions is Na ⁺ The number density of ions is higher.

To further increase the number of sodium transitions in such mixtures, the number density and/or diffusion coefficient of sodium ions must be further increased relative to other ions. Will expect Na ⁺ Further increases in ion number density are very challenging because the mixture will tend to undergo salt crystallization or precipitation at high Na salt content. The present invention overcomes this challenge. Surprisingly, it has been observed that the addition of very small proportions of highly volatile organic liquids (e.g., ether-based solvents) can significantly increase the solubility limit of certain Na or Li salts in high viscosity organic liquids (e.g., VC) or ionic liquids (e.g., typically from x <0.2 to x>0.3-0.6, or typically from 1M to>5M). This can be achieved at a ratio of ionic liquid (or viscous organic liquid) to volatile organic solvent of up to 10:1, thus keeping the volatile solvent content to a minimum and minimizing the potential flammability of the electrolyte.

As measured in pulsed field gradient NMR (PFG-NMR) experiments, the ion diffusion coefficient depends on the effective radius of the diffusing entity. Due to Na ⁺ Ion and TFSI ^- Strong interactions between ions, na ⁺ Ions can form [ Na (TFSI) _n+1 ] ^n- A complex. Coordination numbers of alkali metal ions have been observed to be as high as n+1=4. The coordination number determines the effective hydrodynamic radius of the complex and thus the diffusion coefficient in the liquid mixture. Stokes-Einstein equation di=k _B T/(cπηr _i ) Can be used to calculate its effective hydrodynamic radius ri from the diffusion coefficient Di of the diffusion entity. The constant c varies between 4 and 6, depending on the shape of the diffusion entity. Comparison of the effective hydrodynamic radii of the cations and anions in the ionic liquid with their van der Waals radii reveals that the c-value of the cations is generally lower than that of the anions. In the case of the EMI-TFSI/Na-TFSI mixture, the hydrodynamic radius of Na is in the range from 0.9 to 1.3 nm. This is approximately [ Na (TFSI) ₂ ] ^- And [ Na (TFSI) ₃ ] ^2- Van der Waals radius of the complex. In the case of BMP-TFSI/Na-TFSI mixtures with x=0.34, let r be assumed _BMP 0.55nm and directed against BMP ⁺ The effective hydrodynamic radius of the diffused Na complex is r, as is the c value of the diffused Na complex _Na ＝(D _BMP /D _Na )r _BMP And approximately 1.3nm. The r is _Na The values indicate that in mixtures containing low salt concentrations, the sodium coordination number in the diffusion complex is at least 2.

Due to TFSI ^- The number of ions is not high enough to form a significant amount of [ Na (TFSI) ₃ ] ^2- Complexes, therefore most sodium ions should be treated with [ Na (TFSI) ₂ ] ^- The complex forms diffuse. On the other hand, if a higher Na salt concentration is achieved without crystallization (e.g. in our quasi-solid electrolyte), the mixture should contain a considerable amount of neutral [ Na (TFSI)]Complexes, which are smaller (r _[Na(TFSI)] Approximately 0.5 nm) and should have a higher diffusivity. Thus, a higher salt concentration will not only increase the number density of sodium ions, but will also result in a higher diffusion coefficient of the diffuse sodium complex relative to the organic cation. The above analysis applies to electrolytes containing organic liquid solvents or ionic liquid solvents, both lithium ions and sodium ions. In all cases, when the alkali metal salt concentration is above the threshold, As the concentration increases further, there will be an increasing number of free or non-clustered alkali metal ions moving between the anode and cathode, providing a sufficient amount of alkali metal ions for intercalation/deintercalation or chemical reactions to take place at the cathode and anode.

In addition to the nonflammability and high alkali metal ion transfer number as discussed above, there are several other benefits associated with using the quasi-solid electrolyte of the present invention. For example, the quasi-solid electrolyte can significantly enhance the cycling and safety performance of rechargeable alkali metal cells by effectively inhibiting dendrite growth. It is generally believed that dendrites begin to grow in the nonaqueous liquid electrolyte when anions are depleted near the electrode where plating occurs. In ultra-high concentration electrolytes, a large amount of anions are present to retain cations (Li ⁺ Or Na (or) ⁺ ) Balance with anions. In addition, space charges generated by anion depletion are extremely small, which is disadvantageous for dendrite growth. In addition, the quasi-solid electrolyte provides a large amount of available sodium ion flux due to the ultra-high Na salt concentration and high Na ion transfer number, and increases the mass transfer rate of sodium ions between the electrolyte and the sodium electrode, thereby enhancing deposition uniformity and dissolution of sodium during charge/discharge. In addition, the localized high viscosity caused by the high concentration will increase the pressure from the electrolyte to inhibit dendrite growth, potentially leading to more uniform deposition on the anode surface. The high viscosity may also limit anion convection near the deposition area, thereby promoting more uniform deposition of sodium ions. The same reasoning applies to lithium metal batteries. These reasons are believed (alone or in combination) to be the reasons for: no dendrite-like characteristics have been observed to date for any of the large number of rechargeable alkali metal cells we have studied.

In a preferred embodiment, the anode active material is a prelithiated version of graphene sheets selected from pristine graphene, graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide, hydrogenated graphene, graphene nitride, chemically functionalized graphene, or a combination thereof. The starting graphite material used to produce any of the above-described graphene materials may be selected from natural graphite, synthetic graphite, mesophase carbon, mesophase pitch, mesophase carbon microspheres, soft carbon, hard carbon, coke, carbon fibers, carbon nanofibers, carbon nanotubes, or a combination thereof. Graphene materials are also good conductive additives for anode and cathode active materials of lithium batteries.

The constituent graphene planes of the graphite crystallites in the natural or artificial graphite particles may be expanded and extracted or isolated to obtain single graphene sheets of hexagonal carbon atoms that are monoatomically thick, provided that the interplanar van der waals forces can be overcome. An isolated single graphene plane of carbon atoms is commonly referred to as a monolayer graphene. A stack of a plurality of graphene planes bonded by van der waals forces in the thickness direction, which has a pitch between graphene planes of about 0.3354nm, is generally called a multi-layered graphene. The multi-layer graphene platelets have up to 300 layers of graphene planes (< 100nm in thickness), but more typically up to 30 graphene planes (< 10nm in thickness), even more typically up to 20 graphene planes (< 7nm in thickness), and most typically up to 10 graphene planes (commonly referred to as few-layer graphene in the scientific community). Single-layer graphene sheets and multi-layer graphene sheets are collectively referred to as "nanographene platelets" (NGPs). Graphene sheets/platelets (collectively referred to as NGPs) are a new class of carbon nanomaterials (2-D nanocarbons) that differ from 0-D fullerenes, 1-D CNTs or CNFs, and 3-D graphites. As is generally understood in the art, graphene materials (isolated graphene sheets) are not (and do not include) Carbon Nanotubes (CNTs) or Carbon Nanofibers (CNFs).

In one method, the graphene material is obtained by intercalation of natural graphite particles with strong acids and/or oxidants to obtain Graphite Intercalation Compounds (GIC) or Graphite Oxides (GO), as shown in fig. 5. The presence of chemical species or functional groups in the interstitial spaces between graphene planes in GIC or GO serves to increase the inter-graphene spacing (d ₀₀₂ As determined by X-ray diffraction), thereby significantly reducing van der waals forces that would otherwise hold the graphene planes together along the c-axis direction. GIC or GO is most often produced by immersing natural graphite powder in sulfuric acid, nitric acid (oxidizing agent) andanother oxidant (e.g., potassium permanganate or sodium perchlorate). If 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 containing discrete and visually identifiable graphite oxide particles dispersed in water. For the production of graphene materials, one of two processing routes can be followed after this rinsing step, briefly described as follows:

Route 1 involves removing water from the suspension to obtain "expandable graphite", which is essentially a mass of dry GIC or dry graphite oxide particles. Exposure of expandable graphite to

At temperatures in the range 800 deg.c-1,050 deg.c for about 30 seconds to 2 minutes, the GIC undergoes 30-300 times rapid volume expansion to form "graphite worms", each of which is an expanded, but still interconnected mass of largely non-separated graphite flakes.

In scheme 1A, these graphite worms (expanded graphite or "network of interconnected/unseparated graphite flakes") can be recompressed to obtain flexible graphite sheets or foils, typically having a thickness in the range of from 0.1mm (100 μm) to 0.5mm (500 μm). Alternatively, for the purpose of producing so-called "expanded graphite flakes", which mainly contain graphite flakes or platelets thicker than 100nm (and therefore not nanomaterials by definition), a low-intensity air mill or shears may be chosen to simply decompose the graphite worms.

In scheme 1B, the expanded graphite is subjected to high intensity mechanical shear (e.g., using an ultrasonic generator, high shear mixer, high intensity air jet mill, or high energy ball mill) to form separate single and multi-layered graphene sheets (collectively referred to as NGP), as disclosed in our U.S. application No. 10/858,814 (06/03/2004) (U.S. patent publication No. 2005/0271574). Single-layer graphene may be as thin as 0.34nm, while multi-layer graphene may have a thickness of up to 100nm, but more typically less than 10nm (commonly referred to as few-layer graphene). A plurality of graphene sheets or platelets may be made into NGP paper sheets using a paper making process. The NGP paper sheet is an example of a porous graphene structural layer used in the method of the present invention.

Route 2 requires ultrasonic treatment of a suspension of graphite oxide (e.g., graphite oxide particles dispersed in water) for the purpose of separating/isolating individual graphene oxide sheets from the graphite oxide particles. This is based on the following point: the spacing between graphene planes has increased from 0.3354nm in natural graphite to 0.6-1.1nm in highly oxidized graphite oxide, significantly reducing van der waals forces holding adjacent planes together. The ultrasonic power may be sufficient to further separate the graphene planar sheets to form fully separated, isolated, or discrete Graphene Oxide (GO) sheets. These graphene oxide sheets may then be chemically or thermally reduced to obtain "reduced graphene oxide" (RGO), which typically has an oxygen content of 0.001% -10% by weight, more typically 0.01% -5% by weight, most typically and preferably less than 2% by weight.

NGP or graphene materials include single and multi-layered (typically less than 10 layers) pristine graphene, graphene oxide, reduced Graphene Oxide (RGO), graphene fluoride, graphene chloride, graphene bromide, graphene iodide, hydrogenated graphene, nitrogenated graphene, chemically functionalized graphene, doped graphene (e.g., doped with B or N) discrete platelets. The pristine graphene has substantially 0% oxygen. RGOs typically have an oxygen content of 0.001% -5% by weight. Graphene oxide (including RGO) may have 0.001% -50% oxygen by weight. All graphene materials, except native graphene, have 0.001% -50% by weight of non-carbon elements (e.g., O, H, N, B, F, cl, br, I, etc.). These materials are referred to herein as non-pristine graphene materials.

Primary graphene (in the form of smaller discrete graphene sheets (typically 0.3 μm to 10 μm)) may be produced by direct sonication (also known as liquid phase puffing or production) or supercritical fluid puffing of graphite particles. Such methods are well known in the art.

Graphene Oxide (GO) may be obtained by immersing a powder or filaments of a starting graphite material (e.g. natural graphite powder) in an oxidizing liquid medium (e.g. a mixture of sulfuric acid, nitric acid and potassium permanganate) in a reaction vessel at the desired temperature for a period of time (typically from 0.5 to 96 hours, depending on the nature of the starting material and the type of oxidizing agent used). As previously described above, the resulting graphite oxide particles may then be subjected to thermal expansion or ultrasound-induced expansion to produce isolated GO flakes. Then can be prepared by using other chemical groups (e.g. -Br, NH ₂ Etc.) to replace-OH groups to convert these GO sheets into various graphene materials.

Fluorinated graphene or graphene fluoride is used herein as an example of a halogenated graphene material group. There are two different methods that have been followed to produce fluorinated graphene: (1) fluorination of pre-synthesized graphene: the process requires the use of a fluorinating agent such as XeF ₂ Or F-based plasma treatment of graphene prepared by mechanical puffing or by CVD growth; (2) puffing of the multilayer graphite fluoride: both mechanical expansion and liquid phase expansion of the graphite fluoride can be readily achieved.

F ₂ Interaction with graphite at high temperature results in covalent graphite fluoride (CF) _n Or (C) ₂ F) _n Forming Graphite Intercalation Compound (GIC) C at low temperature _x F (x is more than or equal to 2 and less than or equal to 24). At (CF) _n The medium carbon atoms are sp3 hybridized and thus the fluorocarbon layer is corrugated, consisting of trans-linked cyclohexane chairs. At (C) ₂ F) _n Only half of the C atoms are fluorinated and each pair of adjacent carbon sheets are linked together by a covalent C-C bond. Systematic studies of the fluorination reaction show that the resulting F/C ratio depends largely on the fluorination temperature, the partial pressure of fluorine in the fluorinated gas, and the physical properties of the graphite precursor, including graphitization degree, particle size, and specific surface area. In addition to fluorine (F) ₂ ) In addition, other fluorinating agents can be used, although most of the prior art references involve the use of F ₂ The gas is fluorinated (sometimes in the presence of fluoride).

In order to expand the layered precursor material into a single layer or a state of several layers, the attractive forces between adjacent layers must be overcome and the layers further stabilized. This can be achieved by covalent modification of the graphene surface with functional groups or by non-covalent modification with specific solvents, surfactants, polymers, or donor-acceptor aromatic molecules. The liquid phase puffing process includes ultrasonic treatment of graphite fluoride in liquid medium.

Nitridation of graphene can be performed by exposing a graphene material (e.g., graphene oxide) to ammonia at high temperatures (200 ℃ -400 ℃). The graphene nitride can also be formed at a lower temperature by a hydrothermal method; for example by sealing GO and ammonia in an autoclave and then heating to 150-250 ℃. Other methods of synthesizing 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 hydrothermal treatment of graphene oxide and urea at different temperatures.

There is no limitation in the type of anode active material or cathode active material that can be used in the practice of the present invention. Preferably, in the lithium battery cell of the present invention, the anode active material is more than Li/Li when the battery is charged ⁺ (i.e., relative to Li.fwdarw.Li as a standard potential) ⁺ +e ^- ) Lithium ions are absorbed at electrochemical potentials of less than 1.0 volt, preferably less than 0.7 volt. In a preferred embodiment, the anode active material of the lithium battery is selected from the group consisting of: (a) particles of lithium metal or lithium metal alloy; (b) Natural graphite particles, artificial graphite particles, mesophase Carbon Microbeads (MCMB), carbon particles (including soft 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); (d) Si, ge, sn, pb, sb, bi, zn, al or Cd with other elements, wherein the alloy or compound is stoichiometric or non-stoichiometric; (e) Si, ge, sn, pb, sb, bi, zn, al, fe, ni, co, ti, mn or Cd oxides, carbides, nitrides, sulfides, phosphides, selenium Compounds and tellurides, and mixtures or composites thereof; (f) a prelithiated version thereof; (g) prelithiation of 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 an anode active material containing a sodium intercalation compound selected from the group consisting of: petroleum coke, carbon black, amorphous carbon, activated carbon, hard carbon (carbon that is difficult to graphitize), soft carbon (carbon that can be easily graphitized), template carbon, hollow carbon nanowires, hollow carbon spheres, titanates, niti 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 to 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 、C ₈ Na ₂ F ₄ 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 a combination thereof.

A wide variety of cathode active materials can be used to practice the lithium battery cells of the present invention. The cathode active material is typically a lithium intercalation compound or lithium-absorbing compound that is capable of storing lithium ions when the lithium battery is discharged and releasing lithium ions into the electrolyte upon recharging. The cathode active material may be selected from inorganic materials, organic or polymeric materials, metal oxide/phosphate/sulfide (the most desirable type of inorganic cathode material), or combinations thereof.

The group of metal oxides, metal phosphates, and metal sulfides consists of lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium vanadium oxide, lithium transition metal oxide, lithium mixed metal oxide, lithium iron phosphate, lithium manganese phosphate, lithium vanadium phosphate, lithium mixed metal phosphates, transition metal sulfides, and combinations thereof. In particular, the lithium vanadium oxide may be selected from the group consisting of: VO (VO) ₂ 、Li _x VO ₂ 、V ₂ O ₅ 、Li _x V ₂ O ₅ 、V ₃ O ₈ 、Li _x V ₃ O ₈ 、Li _x V ₃ O ₇ 、V ₄ O ₉ 、Li _x V ₄ O ₉ 、V ₆ O ₁₃ 、Li _x V ₆ O ₁₃ A doping profile thereof, derivatives thereof, and combinations thereof, 0.1<x<5. The lithium transition metal oxide may be selected from layered compounds LiMO ₂ Spinel-type compound LiM ₂ O ₄ Olivine-type compound LiMPO ₄ Silicate compound Li ₂ MSiO ₄ Hydroxy phosphorus lithium iron stone compound LiMPO ₄ F. Borate compound LiMBO ₃ Or combinations thereof, wherein M is a transition metal or a mixture of transition metals.

Other inorganic materials used as the cathode active material may be selected from sulfur, sulfur compounds, lithium polysulfides, transition metal dichalcogenides, transition metal trichalcogedes, or combinations thereof. Concrete embodimentsThe inorganic material is selected from TiS ₂ 、TaS ₂ 、MoS ₂ 、NbSe ₃ 、MnO ₂ 、CoO ₂ Iron oxide, vanadium oxide, or a combination thereof. These will be discussed further later.

Specifically, the inorganic material may be selected from: (a) bismuth selenide or bismuth telluride, (b) a transition metal di-or tri-chalcogenide, (c) a sulfide, selenide, or telluride of niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, cobalt, manganese, iron, nickel, or a transition metal; (d) boron nitride, or (e) combinations thereof.

The organic material or polymeric material may be selected from the group consisting of poly (anthraquinone thioether) (PAQS), lithium oxycarbide, 3,4,9, 10-perylenetetracarboxylic dianhydride (PTCDA), poly (anthraquinone thioether), pyrene-4, 5,9, 10-tetraketone (PYT), polymer-bonded PYT, triazenes, redox-active organic materials, tetracyanoquinodimethane (TCNQ), tetracyanoethylene (TCNE), 2,3,6,7,10, 11-Hexamethoxytriphenylene (HMTP), poly (5-amino-1, 4-dihydroxyanthraquinone) (PADAQ), phosphazene disulfide polymers ([ (NPS) ₂ ) ₃ ]n), lithiated 1,4,5, 8-naphthalene tetralin formaldehyde polymers, hexaazabinaphthyl (HATN), hexaazatriphenylene hexanitrile (HAT (CN) ₆ ) 5-benzylidenyl hydantoin, isatin lithium salt, pyromellitic diimide lithium salt, tetrahydroxy-p-benzoquinone derivative (THQLi) ₄ ) N, N ' -diphenyl-2, 3,5, 6-tetratone piperazine (PHP), N ' -diallyl-2, 3,5, 6-tetratone piperazine (AP), N ' -dipropyl-2, 3,5, 6-tetratone piperazine (PRP), thioether polymers, quinone compounds, 1, 4-benzoquinone, 5,7,12,14-Pentacene Tetratone (PT), 5-amino-2, 3-dihydro-1, 4-dihydroxyanthraquinone (ADDAQ), 5-amino-1, 4-dihydroxyanthraquinone (ADAQ), quinone calixarene, li ₄ C ₆ O ₆ 、Li ₂ C ₆ O ₆ 、Li ₆ C ₆ O ₆ Or a combination thereof.

The organic material may be selected from a phthalocyanine compound selected from copper phthalocyanine, zinc phthalocyanine, tin phthalocyanine, iron phthalocyanine, lead phthalocyanine, nickel phthalocyanine, vanadyl phthalocyanine, chromium phthalocyanine fluoride, magnesium phthalocyanine, manganese phthalocyanine, dilithium phthalocyanine, aluminum phthalocyanine chloride, cadmium phthalocyanine, gallium phthalocyanine chloride, cobalt phthalocyanine, silver phthalocyanine, metal-free phthalocyanine, chemical derivatives thereof, or combinations thereof.

The lithium intercalation compound or lithium-absorbing compound may be selected from metal carbides, metal nitrides, metal borides, metal dichalcogenides, or combinations thereof. Preferably, the lithium intercalation compound or lithium-absorbing compound is selected from an oxide, dichalcogenide, trichalcogenide, sulfide, selenide, or telluride of niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, vanadium, chromium, cobalt, manganese, iron, or nickel in nanowire, nanoplate, nanoribbon, or nanoplatelet form.

We have found that a wide variety of two-dimensional (2D) inorganic materials can be used as cathode active materials in the lithium batteries of the present invention prepared by the direct active material-electrolyte injection method of the present invention. Layered materials represent a diverse source of 2D systems that can exhibit unexpected electronic properties and good affinity for lithium ions. Although graphite is the best known layered material, transition Metal Dichalcogenides (TMD), transition Metal Oxides (TMO), and a variety of other compounds such as BN, bi ₂ Te ₃ And Bi (Bi) ₂ Se ₃ Is also a potential source of 2D material.

Preferably, the lithium intercalation compound or lithium-absorbing compound is selected from nano-discs, nano-platelets, nano-coatings, or nano-sheets of an inorganic material selected from: (a) bismuth selenide or bismuth telluride, (b) a transition metal di-or tri-chalcogenide, (c) a sulfide, selenide, or telluride of niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, cobalt, manganese, iron, nickel, or a transition metal; (d) boron nitride, or (e) a combination thereof; wherein the disc, platelet or sheet has a thickness of less than 100 nm. The lithium intercalation compound or lithium-absorbing compound may contain nanoplates, nanoplatelets, nanocoating, or nanoplatelets of a compound selected from: (i) bismuth selenide or bismuth telluride, (ii) transition metal dichalcogenides or trichalcogenide, (iii) sulfide, selenide, or telluride of niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, cobalt, manganese, iron, nickel, or transition metals; (iv) Boron nitride, or (v) a combination thereof, wherein the disk, platelet, coating, or sheet has a thickness of less than 100 nm.

In the rechargeable sodium cell, the cathode active material may contain a sodium intercalation compound selected from: naFePO ₄ (sodium iron phosphate), na _0.7 FePO ₄ 、Na _1.5 VOPO ₄ F _0.5 、Na ₃ V ₂ (PO ₄ ) ₃ 、Na ₃ V2(PO ₄ ) ₂ F ₃ 、Na ₂ FePO ₄ F、NaFeF ₃ 、NaVPO ₄ F、Na ₃ V ₂ (PO ₄ ) ₂ F ₃ 、Na _1.5 VOPO ₄ F _0.5 、Na ₃ V ₂ (PO ₄ ) ₃ 、NaV ₆ O ₁₅ 、Na _x VO ₂ 、Na _0.33 V ₂ O ₅ 、Na _x CoO ₂ (sodium cobalt oxide), 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 (sodium manganese bronze), na _0.44 MnO ₂ 、Na _0.44 MnO ₂ /C、Na ₄ Mn ₉ O ₁₈ 、NaFe ₂ Mn(PO ₄ ) ₃ 、Na ₂ Ti ₃ O ₇ 、Ni _1/3 Mn _1/3 Co _1/3 O ₂ 、Cu _0.56 Ni _0.44 HCF (copper and nickel hexacyanoferrate), niHCF (nickel hexacyanoferrate), na _x CoO ₂ 、NaCrO ₂ 、Na ₃ Ti ₂ (PO ₄ ) ₃ 、NiCo ₂ O ₄ 、Ni ₃ S ₂ /FeS ₂ 、Sb ₂ O ₄ 、Na ₄ Fe(CN) ₆ /C、NaV _1-x Cr _x PO ₄ F、Se _y S _z (selenium and selenium/sulfur, z/y from 0.01 to 100), se (S-free), dawsonite, or combinations thereof.

Alternatively, the cathode active material may be selected from a functional material or a nanostructured material having an alkali metal ion capturing functional group or an alkali metal ion storage surface in direct contact with the electrolyte. Preferably, the functional group reacts reversibly with an alkali metal ion, forms a redox pair with an alkali metal ion, or forms a chemical complex with an alkali metal ion. The functional or nanostructured material may be selected from the group consisting of: (a) Nanostructured or porous disordered carbon materials selected from soft carbon, hard carbon, polymeric carbon or carbonized resins, mesophase carbon, coke, carbonized pitch, carbon black, activated carbon, nano-honeycomb carbon foam or partially graphitized carbon; (b) Nano graphene platelets selected from single-layer graphene platelets or multi-layer graphene platelets; (c) Carbon nanotubes selected from single-walled carbon nanotubes or multi-walled carbon nanotubes; (d) Carbon nanofibers, nanowires, metal oxide nanowires or fibers, conductive polymer nanofibers, or a combination thereof; (e) carbonyl-containing organic or polymeric molecules; (f) a functional material containing carbonyl, carboxyl or amine groups; and combinations thereof.

The functional or nanostructured material may be selected from the group consisting of: 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 (sodium terephthalate), na ₂ C ₆ H ₄ O ₄ (trans-sodium muconate), 3,4,9, 10-perylene tetracarboxylic-dianhydride (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 nanostructure material has a structure selected from the group consisting of-COOH, =o, -NH ₂ -OR-COOR, wherein R is a hydrocarbon group.

Non-graphene 2D nanomaterials (single or few layers (up to 20 layers)) can be produced by several methods: mechanical splitting, laser ablation (e.g., using laser pulses to ablate TMD into monolayers), liquid phase puffing, and synthesis by thin film techniques such as PVD (e.g., sputtering), evaporation, vapor phase epitaxy, liquid phase epitaxy, chemical vapor phase epitaxy, molecular Beam Epitaxy (MBE), atomic Layer Epitaxy (ALE), and plasma assisted versions thereof.

A wide range of electrolytes can be used in the practice of the present invention. Most preferred are nonaqueous organic and/or ionic liquid electrolytes. The nonaqueous electrolyte to be used herein may be produced by dissolving an electrolyte salt in a nonaqueous solvent. Any known nonaqueous solvent that has been used as a solvent for a lithium secondary battery may be used. It may be preferable to use a nonaqueous solvent mainly composed of a mixed solvent containing Ethylene Carbonate (EC) and at least one kind of nonaqueous solvent having a melting point lower than the above ethylene carbonate and a donor number of 18 or less (hereinafter referred to as a second solvent). This non-aqueous solvent is advantageous because it: (a) Is stable to negative electrodes containing carbonaceous materials that develop well in graphite structure; (b) effectively inhibiting the reduction or oxidative decomposition of the electrolyte; and (c) high conductivity. A nonaqueous electrolyte consisting of only Ethylene Carbonate (EC) is advantageous because it is relatively stable to decomposition by reduction of graphitized carbonaceous materials. However, the melting point of EC is relatively high, 39 ℃ to 40 ℃, and the viscosity thereof is relatively high, so that the conductivity thereof is low, thus making EC alone unsuitable for use as a secondary battery electrolyte operating at room temperature or lower. The second solvent to be used with the EC in the mixture acts to lower the viscosity of the solvent mixture than the viscosity of the EC alone, thereby promoting ionic conductivity of the mixed solvent. Further, when the second solvent having a donor number of 18 or less (the donor number of ethylene carbonate is 16.4) is used, the above-mentioned ethylene carbonate can be easily and selectively solvated with lithium ions, so that the reduction reaction of the second solvent with the carbonaceous material which is supposed to be well developed in graphitization is suppressed. In addition, when the number of donors of the second solvent is controlled to not more than 18, the oxidative decomposition potential of the lithium electrode can be easily increased to 4V or more, so that a high-voltage lithium secondary battery can be manufactured.

Preferred second solvents are dimethyl carbonate (DMC), methyl Ethyl Carbonate (MEC), diethyl carbonate (DEC), ethyl propionate, methyl propionate, propylene Carbonate (PC), gamma-butyrolactone (gamma-BL), acetonitrile (AN), ethyl Acetate (EA), propyl Formate (PF), methyl Formate (MF), toluene, xylene, and Methyl Acetate (MA). These second solvents may be used alone or in combination of two or more. More desirably, the second solvent should be selected from those having a donor number of 16.5 or less. The viscosity of the second solvent should preferably be 28cps or less at 25 ℃.

The mixing ratio of the above-mentioned ethylene carbonate in the mixed solvent should preferably be 10 to 80% by volume. If the mixing ratio of the ethylene carbonate falls outside this range, the conductivity of the solvent may be lowered or the solvent tends to be decomposed more easily, thereby deteriorating the charge/discharge efficiency. More preferred mixing ratios of ethylene carbonate are 20% to 75% by volume. When the mixing ratio of ethylene carbonate in a nonaqueous solvent is increased to 20% by volume or more, the solvation effect of ethylene carbonate on lithium ions is promoted, and the solvolysis inhibition effect thereof can be improved.

Examples of preferred mixed solvents are those comprising EC and MEC; including EC, PC and MEC; comprising EC, MEC and DEC; comprising EC, MEC and DMC; and compositions comprising EC, MEC, PC and DEC; wherein the volume ratio of the MEC is controlled in the range from 30% to 80%. By selecting the volume ratio of MEC in the range from 30% to 80%, more preferably 40% to 70%, the conductivity of the solvent can be improved. For the purpose of suppressing the decomposition reaction of the solvent, an electrolyte having carbon dioxide dissolved therein may be used, thereby effectively improving both the capacity and the cycle life of the battery. The electrolyte salt to be incorporated into the non-aqueous electrolyte may be selected from lithium salts such as lithium perchlorate (LiClO) ₄ ) Lithium hexafluorophosphate (LiPF) ₆ ) Lithium fluoroborate (LiBF) ₄ ) Lithium hexafluoroarsenate (LiAsF) ₆ ) Lithium triflate (LiCF) ₃ SO ₃ ) And bis (trifluoromethylsulfonyl) amineLithium imide [ LiN (CF) ₃ SO ₂ ) ₂ ]. Wherein, liPF ₆ 、LiBF ₄ And LiN (CF) ₃ SO ₂ ) ₂ Is preferred. The content of the above electrolyte salt in the nonaqueous solvent is preferably 0.5 to 2.0mol/l.

For sodium cells, the electrolyte (including nonflammable quasi-solid electrolytes) may contain a sodium salt preferably selected from the group consisting of: sodium perchlorate (NaClO) ₄ ) Sodium hexafluorophosphate (NaPF) ₆ ) Sodium fluoroborate (NaBF) ₄ ) Sodium hexafluoroarsenate, sodium trifluoro-methanesulfonate (NaCF) ₃ SO ₃ ) Sodium bis-trifluoromethylsulfonimide (NaN (CF) ₃ SO ₂ ) ₂ ) An ionic liquid salt, or a combination thereof.

Ionic liquids consist of ions only. Ionic liquids are low melting salts that are either molten or liquid above the desired temperature. For example, if the melting point of the salt is below 100 ℃, it is considered an ionic liquid. If the melting temperature is equal to or lower than room temperature (25 ℃), the salt is referred to as Room Temperature Ionic Liquid (RTIL). Due to the combination of large cations and charge delocalized anions, IL salts are characterized by weak interactions. This results in a low tendency to crystallize due to flexibility (anions) and asymmetry (cations).

Typical and well known ionic liquids are formed by the combination of 1-ethyl-3-methylimidazolium (EMI) cations and N, N-bis (trifluoromethane) sulfonamide (TFSI) anions. The combination produces a fluid having an ionic conductivity comparable to many organic electrolyte solutions and a low propensity to decompose and low vapor pressure up to about 300-400 ℃. This means an electrolyte that is typically low in volatility and nonflammable, and thus much safer for the battery.

Ionic liquids consist essentially of organic ions, which have a substantially infinite number of structural variations due to the ease of preparation of their various components. Thus, various salts can be used to design ionic liquids having desirable characteristics 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 have different classes, which basically include aprotic, protic, and zwitterionic types, each of which is suitable for a particular application.

Common cations for Room Temperature Ionic Liquids (RTILs) include, but are not limited to, tetraalkylammonium, di-, tri-and tetra-alkylimidazolium, alkylpyridinium, dialkyl-pyrrolidinium, dialkylpiperidinium, tetraalkylphosphonium and trialkylsulfonium. Common anions of RTILs 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-C ₃ F ₇ BF ₃ ^- 、n-C ₄ F ₉ BF ₃ ^- 、PF ₆ ^- 、CF ₃ CO ₂ ^- 、CF ₃ SO ₃ ^- 、N(SO ₂ CF ₃ ) ₂ ^- 、N(COCF ₃ )(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 ^- Etc. In contrast, imidazolium or sulfonium based cations with, for example, alCl ₄ ^- 、BF ₄ ^- 、CF ₃ CO ₂ ^- 、CF ₃ SO ₃ ^- 、NTf ₂ ^- 、N(SO ₂ F) ₂ ^- Or F (HF) _2.3 ^- Combinations of the isostere halide anions result in RTILs with good working conductivity.

RTILs can have typical properties such as high intrinsic ionic conductivity, high thermal stability, low volatility, low (near zero) vapor pressure, nonflammability, ability to remain liquid over a wide range of temperatures above and below room temperature, high polarity, high viscosity, and a wide electrochemical window. These properties are desirable properties in addition to high viscosity when referring to the use of RTILs as electrolyte components (salts and/or solvents) in supercapacitors.

Hereinafter, we provide some examples of several different types of anode active materials, cathode active materials, and porous current collector materials (e.g., graphite foam, graphene foam, and metal foam) to illustrate the best mode of practicing the invention. These illustrative examples, as well as other portions of the specification and drawings, are well known, individually or in combination, to enable one of ordinary skill 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) nanoplatelets from natural graphite powder

Natural Graphite from the eastern Graphite company (Huadong Graphite co.) (peninsula china) was used as starting material. GO is obtained by following the well-known modified heimer method (Hummers method), which involves two oxidation stages. In a typical procedure, the first oxidation is carried out under the following conditions: 1100mg of graphite was placed in a 1000mL long-necked flask. Then, 20g of K was added to the flask ₂ S ₂ O ₈ 20g of P ₂ O ₅ And 400mL of concentrated H ₂ SO ₄ Aqueous solution (96%). The mixture was heated at reflux for 6 hours and then left undisturbed at room temperature for 20 hours. The graphite oxide was filtered and rinsed with copious amounts of distilled water until neutral pH. The wet cake material is recovered at the end of this first oxidation.

For the second oxidation process, the wet cake previously collected was placed in a solution containing 69mL of concentrated H ₂ SO ₄ Aqueous (96%) in a long-necked flask. The flask was kept in an ice bath while slowly adding 9g KMnO ₄ . Care was taken to avoid overheating. The resulting mixture was stirred at 35 ℃ for 2 hours (the sample turned dark green in color) and then 140mL of water was added. After 15min, by adding 420mL of water and 15mL of 30wt.% H ₂ O ₂ To stop the reaction. At this stage the colour of the sample turned bright yellow. To remove the metal ions, the mixture was filtered and rinsed with 1:10 aqueous HCl. Will collectIs gently centrifuged at 2700g and rinsed with deionized water. The final product was a wet cake containing 1.4wt.% GO (as estimated from dry extract). Subsequently, a liquid dispersion of GO platelets was obtained by mild sonication of the wet-cake material diluted in deionized water.

Surfactant-stabilized RGO (RGO-BS) is obtained by diluting a wet cake in an aqueous solution of a surfactant instead of pure water. A mixture of commercially available sodium cholate (50 wt.%) and sodium deoxycholate (50 wt.%) salts supplied by Sigma Aldrich was used. The surfactant weight fraction was 0.5wt.%. The score was kept constant for all samples. Sonication was performed using a must be letter S-250A (Branson) operated at 20kHz frequency equipped with a 13mm step breaker horn and a 3mm conical microtip. For example, 10mL of an aqueous solution containing 0.1wt.% GO is sonicated for 10min and then centrifuged at 2700g for 30min to remove any undissolved large particles, aggregates, and impurities. Chemical reduction to obtain GO as such to produce RGO is performed by following a method involving placing 10mL of 0.1wt.% GO in water in a 50mL long neck flask. Then, 10. Mu.L of 35wt.% N ₂ H ₄ (hydrazine) aqueous solution and 70mL of 28wt.% NH ₄ An aqueous OH (ammonia) solution is added to the mixture, which is stabilized by a surfactant. The solution was heated to 90 ℃ and refluxed for 1h. The pH measured after the reaction was about 9. The color of the sample changed to dark black during the reduction reaction.

In certain lithium batteries of the invention, RGO is used as a conductive additive in either or both of the anode and cathode active materials. In selected lithium ion cells, pre-lithiated RGOs (e.g., rgo+lithium particles or RGOs pre-deposited with a lithium coating) are also used as anode active materials.

For comparative purposes, slurry coating and drying procedures were performed to produce conventional electrodes. One anode and one cathode, with a separator disposed between the two electrodes, are then assembled and encapsulated in an Al plastic laminate packaging envelope, and then a liquid electrolyte is injected to form a prior art lithium battery cell.

Example 2: preparation of raw graphene sheets (0% oxygen)

Recognizing the possibility that the high number of defects in GO sheets acts to reduce the electrical conductivity of individual graphene planes, we decided to investigate whether using virgin graphene sheets (non-oxidized and oxygen-free, non-halogenated and halogen-free, etc.) could produce an electrically conductive additive with high electrical and thermal conductivity. Pre-lithiated pristine graphene is also used as an anode active material. The raw graphene sheets are produced by using direct sonication or a liquid phase production process.

In a typical procedure, 5 grams of graphite flakes milled to a size of about 20 μm or less are dispersed in 1,000mL deionized water (containing 0.1% dispersant by weight, from DuPontFSO) to obtain a suspension. An ultrasonic energy level of 85W (Branson S450 ultrasonic generator) was used for puffing, separation and size reduction of graphene sheets for a period of 15 minutes to 2 hours. The resulting graphene sheets are pristine graphene that has never been oxidized and is oxygen-free and relatively defect-free. The pristine graphene is substantially free of any non-carbon elements.

The pristine graphene sheets are then incorporated into the cell as a conductive additive along with the anode active material (or cathode active material in the cathode) using both the procedure of the present invention to inject the slurry into the foam cells and conventional slurry coating, drying and lamination procedures. Both lithium ion batteries and lithium metal batteries (only injected into the cathode) were investigated.

Example 3: preparation of pre-lithiated graphene fluoride sheets as anode active materials for lithium ion batteries

We have used several methods to produce GF, but only one method is described herein as an example. In a typical process, highly Expanded Graphite (HEG) is prepared from intercalated compound ₂ F·xClF ₃ And (3) preparation. HEG is further fluorinated with chlorine trifluoride vapor to produce Fluorinated Highly Expanded Graphite (FHEG). The pre-cooled Teflon (Teflon) reactor is filled with 20-30mL of liquid pre-cooled ClF ₃ The reactor was closed and cooled to liquid nitrogen temperature. Then, no more than 1g HEG is placed in a container having a container for ClF ₃ The gas enters the reactor and is located in the pores within the reactor. Forms a compound having an approximate formula C within 7-10 days ₂ F an off-white product.

Subsequently, a small amount of FHEG (about 0.5 mg) was mixed with 20-30mL of organic solvent (methanol and ethanol, respectively) and subjected to sonication (280W) for 30min, resulting in the formation of a homogeneous pale yellow dispersion. After removal of the solvent, the dispersion turned into a brown powder. The graphene fluoride powder is mixed with the surface-stabilized lithium powder in a liquid electrolyte so that pre-lithiation occurs.

Example 4: some examples of electrolytes used

Preferred sodium metal salts include: sodium perchlorate (NaClO) ₄ ) Sodium hexafluorophosphate (NaPF) ₆ ) Sodium fluoroborate (NaBF) ₄ ) Sodium hexafluoroarsenate, potassium hexafluoroarsenate, sodium trifluoro-methanesulfonate (NaCF) ₃ SO ₃ ) And sodium bis-trifluoromethylsulfonimide (NaN (CF) ₃ SO ₂ ) ₂ ). The following are good choices of lithium salts that tend to dissolve well in the chosen organic or ionic liquid solvents: lithium fluoroborate (LiBF) ₄ ) Lithium triflate (LiCF) ₃ SO ₃ ) Lithium bis (trifluoromethylsulfonyl) imide (LiN (CF) ₃ SO ₂ ) ₂ Or LITFSI), lithium bis (oxalato) borate (LiBOB), lithium oxalyldifluoroborate (LiBF) ₂ C ₂ O ₄ ) And lithium bis-perfluoroethylsulfonyl imide (LiBETI). A good electrolyte additive for helping stabilize Li metal is LiNO ₃ . Particularly useful ionic liquid-based lithium salts include: lithium bis (trifluoromethanesulfonyl) imide (LiTFSI).

Preferred organic liquid solvents include: ethylene Carbonate (EC), dimethyl carbonate (DMC), methylethyl 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 (teggme), poly (ethylene glycol) dimethyl ether (PEGDME), diethylene glycol dibutyl ether (DEGDBE), 2-ethoxyethyl ether (EEE), hydrofluoroethers (e.g. TPTP), sulfones and sulfolane.

Preferred ionic liquid solvents may be selected from Room Temperature Ionic Liquids (RTILs) having cations selected from: tetraalkylammonium, dialkylimidazolium, alkylpyridinium, dialkylpyrrolidinium, or dialkylpiperidinium. The counter anion is preferably selected from 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 N-N-butyl-N-ethylpyrrolidinium bis (trifluoromethanesulfonyl) imide (BEPyTFSI), N-methyl-N-propylpiperidinium bis (trifluoromethanesulfonyl) imide (PP) ₁₃ TFSI), and N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium bis (trifluoromethylsulfonyl) imide.

Example 5: vapor pressures of some solvents and corresponding quasi-solid electrolytes with various sodium salt molecular ratios.

Several solvents (DOL, DME, PC, AN with or without ionic liquid based co-solvent PP were measured ₁₃ TFSI) is added over a wide molecular ratio range of sodium salts (e.g., sodium fluoroborate (NaBF) ₄ ) Sodium perchlorate (NaClO) ₄ ) Or sodium bis (trifluoromethanesulfonyl) imide (NaTFSI)). Some vapor pressure ratio data (p _s P=vapor pressure of solution/vapor pressure of solvent alone) as a function of lithium salt molecular ratio x, as shown in fig. 2 (a) to 2 (D), and a curve representing raoult's law is plotted. In all cases only up to x<The vapor pressure ratio is 0.15, which corresponds to the theoretical prediction based on the Raoult's law above which the vapor pressure deviates from the Raoult's law in a novel and unprecedented manner. It appears that the vapor pressure decreases at a very high rate when the molecular ratio x exceeds 0.2 and rapidly approaches a minimum or substantially zero when x exceeds 0.4. At very low p _s With a value of/p, the vapor phase of the electrolyte cannot ignite or onceInitiation cannot sustain a flame longer than 3 seconds.

Example 6: some solvents and corresponding quasi-solid electrolytes having a molecular ratio of sodium or lithium salt of x=0.3 have flash points and vapor pressures.

The flash points and vapor pressures of several solvents and their electrolytes with Na or Li salt molecular ratios x=0.3 are presented in table 1 below. It can be noted that any liquid with a flash point below 38.7 ℃ is flammable according to OSHA (occupational safety and health administration) classification. However, to ensure safety, we design the quasi-solid electrolyte to exhibit a flash point significantly higher than 38.7 ℃ (by a large margin, for example at least 50 ° and preferably higher than 150 ℃). The data in table 1 show that a molecular ratio of alkali metal salt added to 0.35 is generally sufficient to meet these criteria. All of our quasi-solid electrolytes are nonflammable.

Table 1: the solvents selected and their flash point and vapor pressure of the electrolyte with alkali metal salt molecular ratio x=0.3 (flash point data for the first 4 liquids are given as reference points).

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^* Any liquid having a flash point below 38.7 ℃ is flammable according to OSHA (occupational safety and health administration) classification.

^** 1 normal atmospheric pressure=101, 325 pa=101.325 kpa=1, 013.25hpa.1 Torr=133.3 Pa=0.1333 kPa

Example 7: number of alkali metal ion transfer in several electrolytes

Several types of electrolytes have been investigated (e.g., naffsI salt/(emimtfsi+dme) solvent) Na relative to lithium salt molecular ratio ⁺ Ion transfer number, and representative results are summarized in fig. 3 (a) to 3 (C). Generally, na in low salt concentration electrolytes ⁺ The ion transfer number decreases with increasing concentration from x=0 to x=0.2-0.35. However, above the molecular ratio of x=0.2-0.35, the number of transitions increases with increasing salt concentration, indicating Na ⁺ Radical changes in ion transport mechanisms. This is explained in the theoretical section above. When Na is ⁺ Ion in low salt concentration electrolyte (e.g., x<0.2 Na) during traveling ⁺ The ion may drag multiple solvated molecules therewith. Such co-migration of clusters of charged species may be further hindered if the fluid viscosity increases as more salt is dissolved in the solvent. In contrast, when an ultra-high concentration of sodium salt (having x>0.2 Na) of the composition ⁺ The number of ions may greatly exceed available solvating molecules that might otherwise cluster sodium ions, thereby forming polyionic complex species and slowing down their diffusion process. The high Na ⁺ The ion concentration makes it possible to have more "free Na ⁺ Ions "(non-clustered) to provide higher Na ⁺ Number of transitions (thus providing easy Na) ⁺ Transmission). The sodium ion transport mechanism changes from a multi-ion complex dominated mechanism (with an overall large hydrodynamic radius) to having a large amount of available free Na ⁺ Single ion dominant mechanisms of ions (with smaller hydrodynamic radii). The observation further identifies: a sufficient amount of Na ⁺ Ions can move rapidly through or from the quasi-solid electrolyte to make themselves readily available for interaction or reaction with the cathode (during discharge) or anode (during charge), thereby ensuring good rate performance of the sodium secondary cell. Most importantly, these highly concentrated electrolytes are nonflammable and safe. To date, it has been difficult to obtain combined safety, easy sodium ion transport, and electrochemical performance characteristics for all types of sodium and lithium secondary batteries.

Example 8: lithium iron phosphate (LFP) cathode for lithium metal batteries

LFP powder (uncoated or carbon coated) is commercially available from several sources. In this example, graphene Sheets (RGOs) and Carbon Nanofibers (CNFs) are separately contained as conductive filaments in an electrode containing LFP particles as a cathode active material and an electrolyte (containing a lithium salt dissolved in an organic solvent). The lithium salt used in this example includes lithium fluoroborate (LiBF) ₄ ) And the organic solvent is PC, DOL, DEC, and mixtures thereof. A broad range of conductive filament volume fractions from 0.1% to 30% is included in this study. The formation of the electrode layer is completed by using the following sequence of steps:

sequence 1 (S1): liBF is first carried out ₄ The salt was dissolved in a mixture of PC and DOL to form electrolytes having salt concentrations of 1.0M, 2.5M and 3.5M, respectively. (at a concentration of 2.5M or higher, the resulting electrolyte is no longer a liquid electrolyte, it behaves more like a solid in nature, and is therefore the term "quasi-solid") then, RGO or CNT filaments are dispersed in the electrolyte to form a filament-electrolyte suspension. Mechanical shear is used to help form a uniform dispersion. (the filament-electrolyte suspension is quite viscous even at low salt concentrations of 1.0M). The cathode active material LFP particles are then dispersed in a filament-electrolyte suspension to form a quasi-solid electrode material.

Sequence 2 (S2): liBF is first carried out ₄ The salt was dissolved in a mixture of PC and DOL to form electrolytes having salt concentrations of 1.0M, 2.5M and 3.5M, respectively. Then, cathode active material LFP particles are dispersed in an electrolyte to form an active particle-electrolyte suspension. Mechanical shear is used to help form a uniform dispersion. (the active particle-electrolyte suspension is quite viscous even at low salt concentrations of 1.0M). The RGO or CNT filaments are then dispersed in an active particle-electrolyte suspension to form a quasi-solid electrode material.

Sequence 3 (S3): first, a desired amount of RGO or CNT filaments are dispersed in a liquid solvent mixture (pc+dol) in which no dissolved lithium salt is contained. Mechanical shearing is used to help form a uniform suspension of conductive filaments in a solvent. LiBF is then applied ₄ Salts and process for preparing sameLFP particles are added to the suspension, allowing LiBF ₄ The salt was dissolved in the solvent mixture of the suspension to form electrolytes having salt concentrations of 1.0M, 2.5M, and 3.5M, respectively. Simultaneously or subsequently, the LFP particles are dispersed in an electrolyte to form a deformable quasi-solid electrode material comprised of active material particles and conductive filaments dispersed in a quasi-solid electrolyte (not a liquid electrolyte). In the quasi-solid electrode material, the conductive filaments percolation to form a 3D network of electron conducting pathways. The 3D conductive network is maintained when the electrode material is shaped into the electrode of the battery.

The conductivity of the electrodes was measured using a four-point probe method. The results are summarized in fig. 6 (a) and 6 (B). These data indicate that typical percolation of the 3D network of conductive filaments (CNF or RGO) to form electron conduction paths does not occur until the volume fraction of conductive filaments exceeds 10% -12%, except by following the electrodes made in sequence 3. In other words, the step of dispersing the conductive filaments in the liquid solvent must be performed before dissolving the lithium salt or sodium salt in the liquid solvent and before dispersing the active material particles in the solvent. Such a sequence may also result in percolation thresholds as low as 0.5% -2.0% so that the conductive electrode may be produced by using very small amounts of conductive additives, and thus using higher proportions of active material (and higher energy densities). Up to now, these observations were found to be consistent with all types of electrodes containing active material particles, conductive filaments and electrolyte. This is a critical and unexpected process requirement for preparing high performance alkali metal cells with both high energy density and high power density.

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

For comparative purposes, slurry coating and drying procedures were performed to produce conventional electrodes. One anode and one cathode, with a separator disposed between the two electrodes, are then assembled and encapsulated in an Al plastic laminate packaging envelope, and then a liquid electrolyte is injected to form a prior art lithium battery cell. The battery test results are summarized in example 19.

Example 9: v as an example of a transition metal oxide cathode active material for a lithium battery ₂ O ₅

V alone ₂ O ₅ Powders are commercially available. V for preparation of graphene Supported ₂ O ₅ Powder samples, in a typical experiment, are prepared by mixing V ₂ O ₅ Mixing in LiCl water solution to obtain vanadium pentoxide gel. Li obtained by interaction with LiCl solution (Li: V molar ratio is kept at 1:1) ⁺ The exchange gel was mixed with the GO suspension and then placed in a teflon lined stainless steel 35ml autoclave, sealed, and heated up to 180 ℃ for 12 hours. After such hydrothermal treatment, the green solid was collected, thoroughly washed, sonicated for 2 minutes, and dried at 70 ℃ for 12 hours, then mixed with another 0.1% GO in water, sonicated to decompose nanoribbon size, and then spray dried at 200 ℃ to obtain graphene-enclosed composite particles.

Then V is set ₂ O ₅ Powder (with carbon black powder as conductive additive) and graphene-supported V ₂ O ₅ Both powders are incorporated into the cell separately with the liquid electrolyte using both the procedure of the present invention for injecting the slurry into the foam cells of the cathode current collector and the conventional slurry coating, drying and lamination procedures.

Example 10: liCoO as an example of lithium transition metal oxide cathode active material for lithium ion batteries ₂

Commercially available LiCoO ₂ Powders and multi-walled carbon nanotubes (MW-CNTs) are dispersed in a liquid electrolyte to form a quasi-solid electrode. Two types of quasi-solid anodes are prepared to be coupled to a cathode. A graphite particle is contained as an anode active material and another graphene-enclosed Si nanoparticle is contained as an anode active material 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 that are assembled together and then hermetically sealed.

Based on a separate basis, liCoO ₂ The powder, carbon black powder and PVDF resin binder were dispersed in NMP solvent to form a slurry, which was coated on both sides of an Al foil current collector and then dried under vacuum to form a cathode layer. The graphite particles and PVDF resin binder were dispersed in NMP solvent to form a slurry, which was coated on both sides of a Cu foil current collector and then dried under vacuum to form an anode layer. The anode layer, separator, cathode layer were then laminated and encapsulated in an Al plastic housing into which a liquid electrolyte was injected to form a conventional lithium ion battery.

Example 11: organic material (Li ₂ C ₆ O ₆ )

For the synthesis of dilithium rhodizonate (Li) ₂ C ₆ O ₆ ) Rhodizonic acid dihydrate (species 1 in the scheme below) was used as a precursor. Alkaline lithium salt Li ₂ CO ₃ Can be used in aqueous media to neutralize two enedioic acid (enedioic acid) functional groups. The two reactants (rhodizonic acid and lithium carbonate) were reacted in strict stoichiometric amounts for 10 hours to achieve a yield of 90%. Dilithium rhodia (species 2) is readily soluble even in small amounts of water, which means that water molecules are present in species 2. The water was removed in vacuo at 180 ℃ for 3 hours to obtain the anhydrous form (species 3).

Cathode active material (Li ₂ C ₆ O ₆ ) And conductive additives (carbon black, 15%) for 10 minutes, and grinding the resulting blend to produce composite particles. The electrolyte was 1M lithium hexafluorophosphate (LiPF) in PC-EC ₆ )。

It can be noted that of the formula Li ₂ C ₆ O ₆ Are part of a fixed structure, and they do not participate in reversible lithium ion storage and release. This means that lithium ions must come from the anode side. Therefore, a lithium source (e.g., lithium metal or lithium metal alloy) must be present at the anode. As shown in fig. 1 (D), the anode current collector (Cu foil) is deposited with a lithium layer (e.g., by sputtering or electrochemical plating, or by using a lithium foil). This is followed by assembling the lithium coating layer, the porous separator, and the quasi-solid cathode into a cell. Cathode active material and conductive additive (Li ₂ C ₆ O ₆ /C composite particles) are dispersed in a liquid electrolyte. For comparison, corresponding conventional Li metal cells were also fabricated by conventional slurry coating, drying, lamination, encapsulation, and electrolyte injection procedures.

Example 12: metal naphthalocyanine-RGO hybrid cathode of lithium metal battery

Copper phthalocyanine (CuPc) coated graphene sheets were obtained by evaporating CuPc together with a graphene film (5 nm) prepared from a spin-coated RGO-water suspension in a chamber. Cutting and grinding the resulting coated film to produce CuPc-coated graphene sheets, the graphene sheets being used as cathode active materials in lithium metal batteries having lithium metal foil as anode active material and 1.0M and 3.0M LiClO in Propylene Carbonate (PC) solution as electrolyte ₄ 。

Example 13: mos as cathode active material for lithium metal battery ₂ Preparation of RGO hybrid materials

A wide variety of inorganic materials were investigated in this example. For example, by (NH) ₄ ) ₂ MoS ₄ And hydrazine in N, N-Dimethylformamide (DMF) solution of Graphene Oxide (GO) at 200 ℃ to synthesize ultrathin MoS ₂ hybrid/RGO. In a typical procedure, 22mg (NH ₄ ) ₂ MoS ₄ To 10mg GO dispersed in 10ml DMF. The mixture was sonicated at room temperature for about 10min until a clear and homogeneous solution was obtained. Thereafter, 0.1ml of N was added ₂ H ₄ ·H ₂ O. The reaction solution was further sonicated before transferring to a 40mL teflon-lined autoclave30min. The system was heated in an oven at 200 ℃ for 10h. The product was collected by centrifugation at 8000rpm for 5min, washed with DI water and re-collected by centrifugation. The washing step was repeated at least 5 times to ensure removal of most of the DMF. Finally, the dried product is mixed with some carbon fibers and a quasi-solid electrolyte to form a deformable quasi-solid cathode.

Example 14: two-dimensional (2D) layered Bi ₂ Se ₃ Preparation of chalcogenide nanoribbons

(2D) Layered Bi ₂ Se ₃ The preparation of chalcogenide nanoribbons is well known in the art. For example, bi is grown using the vapor-liquid-solid (VLS) method ₂ Se ₃ A nanobelt. On average, the nanoribbons produced herein are 30-55nm thick, with widths and lengths ranging from hundreds of nanometers to a few microns. The longer nanoribbons were subjected to ball milling to reduce the lateral dimensions (length and width) to below 200nm. The nanoribbons produced by these procedures and graphene sheets or expanded graphite sheets are combined with a quasi-solid electrolyte to form a deformable cathode for a lithium metal battery.

Example 15: MXene powder+chemically activated RGO

The MXene is selected from metal carbides such as Ti ₃ AlC ₂ Is produced by etching away some elements in the layered structure. For example, 1M NH was used at room temperature ₄ HF ₂ Aqueous solution as Ti ₃ AlC ₂ Is an etching agent of (a). Typically, the MXene surfaces are terminated with O, OH and/or F groups, which is why they are commonly referred to as M _n+1 X _n T _x Where M is a preceding transition metal, X is C and/or N, T represents a terminal group (O, OH and/or F), n=1, 2 or 3, and X is the number of terminal groups. The MXene material studied included Ti ₂ CT _x 、Nb ₂ CT _x 、V ₂ CT _x 、Ti ₃ CNT _x And Ta ₄ C ₃ T _x . Typically, 35% -95% MXene and 2% -35% graphene sheets are mixed in a quasi-solid electrolyte to form a quasi-solid cathode.

Example 16: graphene supported MnO ₂ Cathode electrodePreparation of active materials

MnO ₂ The powder was synthesized by two methods (each with or without graphene sheets). In one method, 0.1mol/LKMnO was prepared by dissolving potassium permanganate in deionized water ₄ An aqueous solution. To 300mL of isooctane (oil) was added 13.32g of high purity sodium bis (2-ethylhexyl) sulfosuccinate surfactant and stirred well to give an optically clear solution. Then, 32.4mL of 0.1mol/L KMnO was used ₄ The solution and a selected amount of GO solution were added to the solution, which was sonicated for 30min to produce a dark brown precipitate. The product was isolated, washed several times with distilled water and ethanol, and dried at 80 ℃ for 12h. The sample was graphene supported MnO in powder form ₂ Which is dispersed in a CNT-containing electrolyte to form a quasi-solid cathode electrode.

Example 17: graphene-enhanced nano-silicon as anode active material for lithium ion batteries

Graphene-coated Si particles are available from Angstron Energy co., dayton, ohio. The quasi-solid anode electrode was prepared by: raw graphene sheets (as conductive filaments) were dispersed in a PC-DOL (50/50 ratio) mixture, then graphene-coated Si particles (anode active material) were dispersed, and 2.5M lithium hexafluorophosphate (LiPF) was dispersed at 60 °c ₆ ) Dissolved in the mixture solvent. DOL is then removed to obtain a solution containing about 5.0M LiPF in PC ₆ Is a quasi-solid electrolyte of (a). Since LiPF is known at room temperature ₆ The maximum solubility in PC is below 3.0M, so this causes LiPF ₆ Is in a supersaturated state.

Example 18: cobalt oxide (Co) ₃ O ₄ ) Microparticles

Although LiCoO ₂ Is a cathode active material, co ₃ O ₄ Is an anode active material of a lithium ion battery because of LiCoO ₂ At a position relative to Li/Li ⁺ Electrochemical potential of about +4.0 volts, and Co ₃ O ₄ At a position relative to Li/Li ⁺ An electrochemical potential of about +0.8 volts.

The proper amount of inorganic salt Co (NO ₃ ) ₂ ·6H ₂ O and subsequent ammonia solution (NH ₃ ·H ₂ O,25 wt.%) was slowly added to the GO suspension. The resulting precursor suspension was stirred under argon flow for several hours to ensure complete reaction. The Co (OH) obtained ₂ The graphene precursor suspension is divided into two parts. A portion was filtered and dried under vacuum at 70℃to obtain Co (OH) ₂ Graphene composite precursor. Calcining the precursor in air at 450 ℃ for 2h to form layered Co ₃ O ₄ Graphene composite material, said composite material being characterized by having Co overlapping each other ₃ O ₄ Coated graphene sheets.

Example 19: graphene-reinforced tin oxide microparticles as anode active materials

The following procedure was used to pass through SnCl ₄ ·5H ₂ Controlled hydrolysis of O with NaOH to obtain tin oxide (SnO ₂ ) Nanoparticles: snCl is added ₄ ·5H ₂ O (0.95 g,2.7 m-mol) and NaOH (0.212 g,5.3 m-mol) were each dissolved in 50mL of distilled water. The NaOH solution was added dropwise to the tin chloride solution at a rate of 1mL/min with vigorous stirring. The solution was homogenized by sonication for 5 min. Subsequently, the resulting hydrosol was reacted with GO dispersion for 3 hours. To this mixed solution, a few drops of 0.1M H were added ₂ SO ₄ To flocculate the product. The precipitated solid was collected by centrifugation, washed with water and ethanol and dried in vacuo. The dried product was heat-treated at 400 ℃ 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 studied, we prepared lithium ion cells or lithium metal cells using both the present method and the conventional method.

In the case of conventional processes, a typical anode composition comprises 85wt.% active material (e.g., si-or Co ₃ O ₄ -coated graphene sheets), 7wt.% acetylene black (Super-P) and 8wt.% polyvinylidene fluoride binder (P VDF,5wt.% solids content). After coating the slurry on Cu foil, the electrode was dried in vacuum at 120 ℃ for 2h to remove the solvent. In the case of the process of the invention, the binder resin is typically not required or used, thus saving 8% by weight (reduced amount of inactive material). The cathode layer was made in a similar manner (using Al foil as cathode current collector) using conventional slurry coating and drying procedures. The anode layer, separator layer (e.g., celgard 2400 film), and cathode layer are then laminated together and placed in a plastic-Al envelope. For example, 2.8M LiPF dissolved in a mixture of Ethylene Carbonate (EC) and diethyl carbonate (DEC) (EC-DEC, 1:1 v/v) is then injected into the cell ₆ An electrolyte solution. In some cells, ionic liquids are used as the liquid electrolyte. The cell assembly was made in an argon filled glove box.

In the method of the present invention, preferably, the quasi-solid anode, the porous separator, and the quasi-solid cathode are assembled in a protective housing. The bag is then sealed.

Cyclic Voltammetric (CV) measurements were performed using an Abin electrochemical workstation at a typical scan rate of 1 mV/s. In addition, the electrochemical performance of the various cells was also evaluated by constant current charge/discharge cycles at current densities from 50mA/g to 10A/g. For long-term cycling testing, a multi-channel battery tester manufactured by LAND was used.

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 that the battery suffers from a 20% capacity fade based on the initial capacity measured after the desired electrochemical formation.

Example 21: representative test results

For each sample, several current densities (representing charge/discharge rates) were applied to determine the electrochemical response, allowing calculation of the energy density values and power density values required to construct a ragong plot (power density versus energy density). A taber 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 is shown in fig. 7. Three of the 4 data curves are for cells prepared according to the examples of the present invention (with sequences S1, S2, and S3, respectively), while the remaining one is a cell prepared by conventional electrode paste coating (roll coating). From these data several important observations can be made:

both the gravimetric energy density and the power density of the lithium ion battery cells prepared by the method of the present invention are significantly higher than the gravimetric energy density and the power density of their counterparts (denoted "conventional") prepared by conventional roll coating methods. The change from 160 μm anode thickness (coated on a flat solid Cu foil) to 315 μm thickness and the corresponding change in cathode to maintain a balanced capacity ratio resulted in an increase in gravimetric energy density from 165Wh/kg to 230Wh/kg (S1), 235Wh/kg (S2), and 264Wh/kg (S3), respectively. It was also surprising that batteries containing the quasi-solid electrode of the present invention with a 3D network of electron conducting pathways (due to percolation of the conductive filaments) give significantly higher energy density and higher power density.

These large differences cannot be simply attributed to the increase in electrode thickness and mass loading. The differences may be due to the significantly higher active material mass loading (not just mass loading) and higher conductivity associated with the cells of the present invention, the reduced proportion of non-contributing (inactive) components relative to active material weight/volume, and the unexpectedly better utilization of the electrode active material (most, if not all, of the graphite particles and LFP particles contribute to lithium ion storage capacity due to the higher conductivity and the lack of drying pockets or dead spots in the electrode, particularly at high charge/discharge rate conditions).

FIG. 8 shows a Lagong plot (weight power density versus weight energy density) of two cells, both containing graphene-surrounded Si nanoparticles as anode active material and LiCoO ₂ The nanoparticles serve as cathode active materials. Experimental data were obtained from Li-ion battery cells prepared by the method of the invention and Li-ion battery cells prepared by conventional electrode paste coating.

These data show that the gravimetric energy density and the power density of the battery cells prepared by the method of the invention are significantly higher than the gravimetric energy density and the power density of their counterparts prepared by conventional methods. Also, the differences are enormous. The conventionally prepared cells exhibited a gravimetric energy density of 265Wh/kg, but the cells of the present invention gave an energy density of 393Wh/kg (S1) and 421Wh/kg (S3), respectively. Power densities as high as 1425W/kg and 1,654W/kg have also been unprecedented for lithium ion batteries.

These energy density and power density differences are mainly due to the high active material mass loading associated with the cells of the present invention (in the anode>25mg/cm ² In the cathode>45mg/cm ² ) And high electrode conductivity, reduced proportion of non-contributing (non-active) components relative to active material weight/volume, and the ability of the inventive method to better utilize active material particles (all particles being liquid electrolytes and accessible to rapid ionic and electronic kinetics).

Fig. 9 shows dilithium rhodizonate (Li) containing a lithium foil as an anode active material ₂ C ₆ O ₆ ) As cathode active material and lithium salt (LiPF ₆ ) PC/DEC as Lagong plot for lithium metal batteries with organic electrolytes (both 1.5M and 5.0M). Quasi-solid electrodes were prepared according to the sequences S2 and S3 as described in example 8. The data are for three lithium metal cells prepared by the method of the present invention and lithium metal cells prepared by conventional electrode paste coating.

These data show that the gravimetric energy density and the power density of lithium metal cells prepared by the process of the present invention are significantly higher than their counterparts prepared by conventional processes. Also, the differences are dramatic and may be due to significantly higher active material mass loadings (not just mass loadings) and higher conductivities associated with the electrodes of the present invention, reduced proportions of non-contributing (non-active) components relative to active material weight/volume, and unexpectedly better utilization of the electrode active material (most if not all of the active material contributes to lithium ion storage capacity, due to higher conductivities and the lack of drying pockets or dead spots in the electrode, particularly at high charge/discharge rate conditions).

Quite notable and unexpected are the following observations: the gravimetric energy density of the lithium metal-organic cathode cells of the present invention is as high as 515Wh/kg, higher than that of all rechargeable lithium metal or lithium ion batteries reported ever (recall that current Li ion batteries store 150-220Wh/kg based on total cell weight). Furthermore, for lithium batteries based on organic cathode active materials, a gravimetric power density of 1,576W/kg is not conceivable. The cells containing the quasi-solid electrodes prepared according to sequence 3 exhibited significantly higher energy and power densities than the cells of conventional sequence S2. In addition, higher concentrations of electrolyte (quasi-solid electrolyte) are unexpectedly more advantageous for achieving higher energy and power densities.

The above performance characteristics of lithium batteries were also observed with respect to the corresponding sodium batteries. Due to the page limitation, no data for the sodium cell is presented here. However, for example, fig. 10 indicates a ragong plot of two sodium ion capacitors, each containing pre-sodified hard carbon particles as the anode active material and graphene sheets as the cathode active material; one cell has an anode prepared by a conventional slurry coating process and the other cell has a quasi-solid anode prepared according to the method of the present invention. Also, the quasi-solid electrode based electrical core gives a significantly higher energy density and higher power density. Lithium ion capacitors were found to conform to similar trends.

It is important to note that reporting the energy density and power density per weight of active material alone on a Lagong plot may not give a realistic picture of the performance of the assembled supercapacitor cell, as made by many researchers. The weight of other device components must also be taken into account. These non-contributing components, including current collectors, electrolytes, separators, binders, connectors, and encapsulants, are inactive materials and do not contribute to charge storage. They merely add weight and bulk to the device. Thus, it is desirable to reduce the relative proportion of the weight of the non-contributing components and increase the proportion of active material. However, this objective has not been possible using conventional battery production methods. The present invention overcomes this long-standing most serious problem in the field of lithium batteries.

In commercial lithium ion batteries having an electrode thickness of 100-200 μm, the weight proportion of anode active material (e.g., graphite or carbon) in the lithium ion battery is typically from 12% to 17%, and the weight proportion of cathode active material (for inorganic materials, such as LiMn ₂ O ₄ ) From 22% to 41%, or from 10% to 15% for organic or polymeric materials. Thus, a factor of 3 to 4 is often used to extrapolate the energy density or power density of the device (cell) from the characteristics based solely on the weight of the active material. In most scientific papers, the reported characteristics are typically based on the weight of the active material alone, and the electrodes are typically very thin <<100 μm, and most of<<50 μm). The active material weight is typically from 5% to 10% of the total device weight, which means that the actual cell (device) energy density or power density can be obtained by dividing the corresponding active material weight based value by a factor of 10 to 20. The characteristics reported in these papers do not actually appear to be better than the characteristics of commercial batteries, taking this factor into account. Therefore, great care must be taken in reading and interpreting the performance data of the batteries reported in the scientific papers and patent applications.

Claims

1. An alkali metal cell, the alkali metal cell comprising:

(a) A quasi-solid cathode containing 30 to 95% by volume of a cathode active material, 5 to 40% by volume of a first electrolyte containing an alkali metal 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 conduction pathways, whereby the quasi-solid cathode has a molecular weight of from 10 ^-6 A conductivity of S/cm to 300S/cm, wherein the first electrolyte is a quasi-solid electrolyte;

(b) An anode; and

(c) An ion conducting membrane or porous separator disposed between the anode and the quasi-solid cathode;

Wherein the quasi-solid cathode has a thickness of not less than 200 μm and contains more than 65mg/cm ² Is used for the cathode active material mass loading.

2. The alkali metal cell of claim 1, wherein the anode comprises a quasi-solid anode comprising 30% to 95% by volume of an anode active material, 5% to 40% by volume of a second electrolyte comprising an alkali metal salt dissolved in a solvent, and 0.01% to 30% by volume of a conductive additive, wherein the conductive additive comprising conductive filaments forms a 3D network of electron conduction paths, thereby providing the quasi-solid anode with a voltage of from 10 ^-6 Conductivity of S/cm to 300S/cm; wherein the quasi-solid anode has a thickness of not less than 200 μm.

3. The alkali metal cell of claim 1, wherein the first electrolyte is a quasi-solid electrolyte containing a lithium salt or a sodium salt dissolved in a liquid solvent, having a salt concentration of not less than 2.5M.

4. The alkali metal cell according to claim 2, wherein the first electrolyte or the second electrolyte is a quasi-solid electrolyte containing a lithium salt or a sodium salt dissolved in a liquid solvent, having a salt concentration of not less than 2.5M.

5. 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, having a salt concentration of from 3.0M to 14M.

6. The alkali metal cell of claim 2, wherein the first electrolyte or the second electrolyte is a quasi-solid electrolyte containing a lithium salt or a sodium salt dissolved in a liquid solvent, having a salt concentration of from 3.0M to 14M.

7. The alkali metal cell of claim 1, wherein the conductive filaments are selected from carbon fibers, carbon nanotubes, needle coke, carbon whiskers, conductive polymer fibers, conductive material coated fibers, metal wires, combinations thereof, or combinations thereof with non-filament conductive particles.

8. The alkali metal cell of claim 1, wherein the quasi-solid cathode remains from 10 ^-5 Conductivity of S/cm to 100S/cm.

9. The alkali metal cell of claim 1, wherein the quasi-solid cathode remains from 10 ^-3 Conductivity of S/cm to 10S/cm.

10. The alkali metal cell of claim 1, wherein the quasi-solid cathode remains from 10 ^-2 Conductivity of S/cm to 10S/cm.

11. The alkali metal cell of claim 1, wherein the conductive filaments are bonded together at the intersections between the conductive filaments by a resin.

12. The alkali metal cell of claim 1, wherein the quasi-solid cathode contains 0.1% to 20% by volume of the conductive additive.

13. The alkali metal cell of claim 1, wherein the quasi-solid cathode contains 1% to 10% by volume of the conductive additive.

14. The alkali metal cell of claim 1, wherein the amount of cathode active material is 40% to 90% by volume of the quasi-solid cathode.

15. The alkali metal cell of claim 1, wherein the amount of cathode active material is 50% to 85% by volume of the quasi-solid cathode.

16. The alkali metal cell of claim 1, wherein the amount of cathode active material is 50% to 75% by volume of the quasi-solid cathode.

17. The alkali metal cell of claim 1, wherein the first electrolyte is in a supersaturated state.

18. The alkali metal cell of claim 2, wherein the first electrolyte or the second electrolyte is in a supersaturated state.

19. 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.

20. 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.

21. The alkali metal cell of claim 2, wherein the alkali metal cell is a lithium metal cell, or a lithium ion cell and the anode active material is selected from the group consisting of:

(a) Particles of lithium metal or lithium metal alloy;

(b) Mesophase Carbon Microbeads (MCMB), carbon particles, needle coke, carbon nanotubes, and carbon 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) Si, ge, sn, pb, sb, bi, zn, al or Cd with other elements, wherein the alloy or compound is stoichiometric or non-stoichiometric;

(e) Si, ge, sn, pb, sb, bi, zn, al, fe, ni, co, ti, mn or Cd oxides, carbides, nitrides, sulfides, phosphides, selenides, tellurides, and mixtures or composites thereof;

(f) A prelithiated version thereof;

(g) Pre-lithiated graphene sheets; and

a combination thereof.

22. The alkali metal cell of claim 21, wherein the prelithiated graphene sheets are selected from prelithiated versions of pristine graphene, graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide, hydrogenated graphene, nitrogenated graphene, boron doped graphene, nitrogen doped graphene, physically or chemically activated or etched versions thereof, or combinations thereof.

23. 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 contains an alkali intercalation compound selected from: petroleum coke, carbon black, amorphous carbon, activated carbon, template carbon, hollow carbon nanowires, hollow carbon spheres, and NaTi ₂ (PO ₄ ) ₃ 、Na ₂ Ti ₃ O ₇ 、Na ₂ C ₈ H ₄ O ₄ 、Na _x TiO ₂ Carboxylate-based materials, C ₈ H ₆ O ₄ 、C ₈ H ₅ NaO ₄ 、C ₈ Na ₂ F ₄ 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 a combination thereof, wherein x = 0.2 to 1.0.

24. 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 selected from the group consisting of:

a) Particles of sodium metal or sodium metal alloy;

b) Mesophase Carbon Microbeads (MCMB), carbon particles, needle coke, carbon nanotubes, and carbon 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) Si, ge, sn, pb, sb, bi, zn, al, ti, co, ni, mn, cd sodium-containing alloys or intermetallic compounds, and mixtures thereof;

e) Si, ge, sn, pb, sb, bi, zn, al, fe, ti, co, ni, mn, cd sodium-containing oxides, carbides, nitrides, sulfides, phosphides, selenides, tellurides, or antimonides, and mixtures or composites thereof;

f) A sodium salt;

g) Graphene sheets preloaded with sodium ions; and

a combination thereof.

25. 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 contains a lithium intercalation compound selected from the group consisting of: lithium cobalt oxide, doped lithium cobalt oxide, lithium nickel oxide, doped lithium nickel oxide, lithium manganese oxide, doped lithium manganese oxide, lithium vanadium oxide, doped lithium vanadium oxide, lithium iron phosphate, lithium vanadium phosphate, lithium manganese phosphate, metal sulfides, and combinations thereof.

26. 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 contains a lithium intercalation compound or a lithium absorbing compound selected from the group consisting of: an inorganic material, an organic material, or a combination thereof.

27. The alkali metal cell of claim 26, wherein the cathode active material contains a lithium intercalation compound or lithium-absorbing compound selected from the group consisting of: polymeric materials, metal oxides, metal phosphates, metal sulfides, or combinations thereof.

28. The alkali metal cell of claim 27, wherein the metal oxide, the metal phosphate, the metal sulfide is selected from lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium vanadium oxide, lithium iron phosphate, lithium manganese phosphate, lithium vanadium phosphate, transition metal sulfide, or a combination thereof.

29. The alkali metal cell of claim 26, wherein the inorganic material is selected from sulfur, lithium polysulfide, transition metal dichalcogenide, transition metal trichalcogenide, or a combination thereof.

30. The alkali metal cell of claim 26, wherein the inorganic material is selected from TiS ₂ 、TaS ₂ 、MoS ₂ 、NbSe ₃ 、MnO ₂ 、CoO ₂ Iron oxide, vanadium oxide, or a combination thereof.

31. The alkali metal cell of claim 27, wherein the metal oxide comprises a vanadium oxide selected from the group consisting of: VO (VO) ₂ 、Li _x VO ₂ 、V ₂ O ₅ 、Li _x V ₂ O ₅ 、V ₃ O ₈ 、Li _x V ₃ O ₈ 、Li _x V ₃ O ₇ 、V ₄ O ₉ 、Li _x V ₄ O ₉ 、V ₆ O ₁₃ 、Li _x V ₆ O ₁₃ A doping profile thereof, derivatives thereof, and combinations thereof, 0.1<x<5。

32. The alkali metal cell of claim 27, wherein the metal oxide, the metal phosphate, the metal sulfide are selected from layered compounds LiMO ₂ Spinel-type compound LiM ₂ O ₄ Olivine-type compound LiMPO ₄ Silicate compound Li ₂ MSiO ₄ Hydroxy phosphorus lithium iron stone compound LiMPO ₄ F. Borate compound LiMBO ₃ Or combinations thereof, wherein M is a transition metal or a mixture of transition metals.

33. The alkali metal cell of claim 26, wherein the inorganic material is selected from the group consisting of: (a) bismuth selenide or bismuth telluride, (b) a transition metal di-or tri-chalcogenide, (c) a niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, cobalt, manganese, iron, or nickel selenide, or telluride; (d) boron nitride, or (e) combinations thereof.

34. The alkali metal cell of claim 26, wherein the organic material is selected from the group consisting of poly (anthraquinone thioether) (PAQS), 3,4,9, 10-perylenetetracarboxylic dianhydride (PTCDA), pyrene-4, 5,9, 10-tetraketone (PYT), quinone (triazene), tetracyanoquinodimethane (TCNQ), tetracyanoethylene (TCNE), 2,3,6,7,10, 11-Hexamethoxytriphenylene (HMTP), poly (5-amino-1, 4-dihydroxyanthraquinone) (PADAQ), phosphazene disulfide polymers ([ (NPS) ₂ ) ₃ ]n), lithiated 1,4,5, 8-naphthalene tetralin formaldehyde polymers, hexaazabinaphthyl (HATN), hexaazatriphenylene hexanitrile (HAT (CN) ₆ ) 5-benzylidenyl hydantoin, isatin lithium salt, pyromellitic diimide lithium salt, tetrahydroxy-p-benzoquinone derivative (THQLi) ₄ ) N, N ' -diphenyl-2, 3,5, 6-tetratone piperazine (PHP), N ' -diallyl-2, 3,5, 6-tetratone piperazine (AP), N ' -dipropyl-2, 3,5, 6-tetratone piperazine (PRP), 1, 4-benzoquinone, 5,7,12,14-Pentacene Tetratone (PT), 5-amino-2, 3-dihydro-1, 4-dihydroxyanthraquinone (ADDAQ), 5-amino-1, 4-dihydroxyanthraquinone (ADAQ), quinine calixarene, li ₄ C ₆ O ₆ 、Li ₂ C ₆ O ₆ 、Li ₆ C ₆ O ₆ Or a combination thereof.

35. The alkali metal cell of claim 34, wherein the organic material is selected from a thioether polymer selected from poly [ methane trinitrotoluene-tetra (thiomethylene) ] (PMTTM), poly (2, 4-dithiopentene) (PDTP), a polymer containing poly (ethylene-1, 2-tetrathiol) (PETT) as a backbone thioether polymer, a side chain thioether polymer having a backbone consisting of conjugated aromatic moieties and having thioether side chains as side chains, poly (2-phenyl-1, 3-dithiolane) (PPDT), poly (1, 4-bis (1, 3-dithiolane-2-yl) benzene) (PDDTB), poly (tetrahydrobenzodithiophene) (ptdt), poly [1,2,4, 5-tetra (propylthio) benzene ] (PTKPTB), or poly [3,4 (ethylenedithio) thiophene ] (PEDTT).

36. The alkali metal cell of claim 26, wherein the organic material comprises a phthalocyanine compound selected from the group consisting of: copper phthalocyanine, zinc phthalocyanine, tin phthalocyanine, iron phthalocyanine, lead phthalocyanine, nickel phthalocyanine, vanadyl phthalocyanine, chromium fluoride phthalocyanine, magnesium phthalocyanine, manganese phthalocyanine, dilithium phthalocyanine, aluminum phthalocyanine chloride, cadmium phthalocyanine, gallium phthalocyanine chloride, cobalt phthalocyanine, silver phthalocyanine, metal-free phthalocyanine, chemical derivatives thereof, or combinations thereof.

37. The alkali metal cell of claim 26, wherein the lithium intercalation compound or lithium-absorbing compound is selected from a metal carbide, a metal nitride, a metal boride, a metal dichalcogenide, or a combination thereof.

38. The alkali metal cell of claim 26, wherein the lithium intercalation compound or lithium-absorbing compound is selected from an oxide, sulfide, selenide, or telluride of niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, vanadium, chromium, cobalt, manganese, iron, or nickel in nanowire, nanodisk, nanoribbon, or nanoplatelet form.

39. The alkali metal cell of claim 26, wherein the lithium intercalation compound or lithium-absorbing compound is selected from nano-discs, nano-coatings, or nano-sheets of an inorganic material selected from: (a) bismuth selenide or bismuth telluride, (b) a transition metal di-or tri-chalcogenide, (c) a niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, cobalt, manganese, iron, or nickel selenide, or telluride; (d) boron nitride, or (e) a combination thereof; wherein the nanoplate, the nanocoating, or the nanoplate has a thickness of less than 100 nm.

40. The alkali metal cell of claim 1, wherein the alkali metal cell is a sodium metal cell or a sodium ion cell and the cathode active material is a cathode active material containing a sodium intercalation compound or sodium absorbing compound selected from the group consisting of: an inorganic material, an organic material, or a combination thereof.

41. The alkali metal cell of claim 40, wherein the cathode active material is a cathode active material containing a sodium intercalation compound or sodium absorbing compound selected from the group consisting of: polymeric materials, metal oxides, metal phosphates, metal sulfides, or combinations thereof.

42. The alkali metal cell of claim 41, wherein said metal oxide, said metal phosphate, said metal sulfide is selected from the group consisting of sodium cobalt oxide, sodium nickel oxide, sodium manganese oxide, sodium vanadium oxide, sodium/potassium transition metal oxide, sodium iron phosphate, sodium manganese phosphate/potassium vanadium phosphate, sodium vanadium phosphate/potassium transition metal sulfide, or a combination thereof.

43. The alkali metal cell of claim 40, wherein said inorganic material is selected from sulfur, lithium polysulfide, transition metal dichalcogenide, transition metal trichalcogenide, or a combination thereof.

44. The alkali metal cell of claim 40, wherein the inorganic material is selected from the group consisting of TiS ₂ 、TaS ₂ 、MoS ₂ 、NbSe ₃ 、MnO ₂ 、CoO ₂ Iron oxide, vanadium oxide, or a combination thereof.

45. The alkali metal cell of claim 40, wherein the alkali metal cell is a sodium metal cell or a sodium ion cell and the cathode active material is a cathode active material containing a sodium intercalation compound selected from the group consisting of: naFePO ₄ 、Na _(1-x) K _x PO ₄ 、Na _0.7 FePO ₄ 、Na _1.5 VOPO ₄ F _0.5 、Na ₃ V ₂ (PO ₄ ) ₃ 、Na ₃ V ₂ (PO ₄ ) ₂ F ₃ 、Na ₂ FePO ₄ F、NaFeF ₃ 、NaVPO ₄ F、NaV ₆ O ₁₅ 、Na _x VO ₂ 、Na _0.33 V ₂ O ₅ 、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 、λ-MnO ₂ 、Na _x K _(1-x) MnO ₂ 、Na _0.44 MnO ₂ 、Na _0.44 MnO ₂ /C、Na ₄ Mn ₉ O ₁₈ 、NaFe ₂ Mn(PO ₄ ) ₃ 、Na ₂ Ti ₃ O ₇ 、Ni _1/3 Mn _1/3 Co _1/3 O ₂ 、Cu _0.56 Ni _0.44 HCF、NiHCF、Na _x MnO ₂ 、NaCrO ₂ 、Na ₃ Ti ₂ (PO ₄ ) ₃ 、NiCo ₂ O ₄ 、Ni ₃ S ₂ /FeS ₂ 、Sb ₂ O ₄ 、Na ₄ Fe(CN) ₆ /C、NaV _1-x Cr _x PO ₄ F、Se _z S _y Se, dawsonite, or a combination thereof, wherein x is from 0.1 to 1.0, y/z = 0.01 to 100.

46. The alkali metal cell of claim 1, wherein the anode contains greater than 15mg/cm ² Is used for the anode active material mass loading.

47. The alkali metal cell of claim 1, wherein the anode contains greater than 20mg/cm ² Is used for the anode active material mass loading.

48. The alkali metal cell of claim 1, wherein the anode contains greater than 30mg/cm ² Is used for the anode active material mass loading.

49. An alkali metal cell, the alkali metal cell comprising:

(a) A quasi-solid anode comprising 30 to 95% by volume of an anode active material, 5 to 40% by volume of an electrolyte comprising an alkali metal salt dissolved in a solvent, and 0.01 to 30% by volume of a conductive additive, wherein the conductive additive comprising conductive filaments forms a 3D network of electron conduction pathways, whereby the quasi-solid anode has a molecular weight of from 10 ^-6 Conductivity of S/cm to 300S/cm, wherein the electrolyte is a quasi-solid electrolyte;

(b) A cathode; and

(c) An ion conducting membrane or porous separator disposed between the cathode and the quasi-solid anode;

wherein the quasi-solid anode has a thickness of not less than 200 μm and contains not less than 35mg/cm ² Is used for the anode active material mass loading.

50. The alkali metal cell of claim 49, wherein the electrolyte is a quasi-solid electrolyte having a salt concentration of not less than 2.5M containing a lithium salt or a sodium salt dissolved in a liquid solvent.

51. The alkali metal cell of claim 49, wherein said electrolyte is a quasi-solid electrolyte containing a lithium salt or sodium salt dissolved in a liquid solvent, having a salt concentration of from 3.0M to 14M.

52. A method of making an alkali metal cell having a quasi-solid electrode, the method comprising:

(a) Combining an amount of active material, an amount of electrolyte, and a conductive additive to form a deformable and conductive electrode material, wherein the conductive additive containing conductive filaments forms a 3D network of electron conduction pathways, wherein the electrolyte is a quasi-solid electrolyte;

(b) Forming the electrode material into a quasi-solid electrode Wherein the forming comprises deforming the electrode material into an electrode shape without interrupting a 3D network of the electron conduction path, thereby causing the electrode to remain no less than 10 ^-6 Conductivity of S/cm;

(c) Forming a second electrode; and is also provided with

(d) Forming an alkali metal cell by combining the quasi-solid electrode and the second electrode;

wherein the quasi-solid electrode is a quasi-solid cathode and contains more than 65mg/cm ² Is used for the cathode active material mass loading; or the quasi-solid electrode is a quasi-solid anode and contains not less than 35mg/cm ² Is used for the anode active material mass loading.

53. The method of claim 52, wherein the electrolyte is a quasi-solid electrolyte having a salt concentration of from 2.5M to 14M containing a lithium salt or sodium salt dissolved in a liquid solvent.

54. The method of claim 52, wherein the electrolyte is a quasi-solid electrolyte comprising a lithium or sodium salt dissolved in a liquid solvent, having a salt concentration of from 3.0M to 11M.

55. The method of claim 52, wherein the conductive filaments are selected from carbon fibers, carbon nanotubes, needle coke, carbon whiskers, conductive polymer fibers, conductive material coated fibers, metal wires, combinations thereof, or combinations thereof with non-filament conductive particles.

56. The method of claim 52, wherein the electrode is maintained from 10 ^-5 Conductivity of S/cm to 300S/cm.

57. The method of claim 52, wherein the deformable electrode material has a composition of at 1,000s ^-1 An apparent viscosity of not less than 10,000Pa-s at an apparent shear rate.

58The method of claim 52, wherein the deformable electrode material has a composition of at least 1,000s ^-1 An apparent viscosity of not less than 100,000Pa-s at an apparent shear rate.

59. The method of claim 52, wherein the amount of active material is 20% to 95% by volume of the electrode material.

60. The method of claim 52, wherein the amount of active material is from 35% to 85% by volume of the electrode material.

61. The method of claim 52, wherein the active material is present in an amount of 50% to 75% by volume of the electrode material.

62. The method of claim 52, wherein the combining step comprises dispersing the conductive filaments into a liquid solvent to form a uniform suspension, followed by adding the active material to the suspension and then dissolving a lithium or sodium salt in the liquid solvent of the suspension.

63. The method of claim 52, wherein the step of combining and forming the electrode material into a quasi-solid electrode comprises dissolving a lithium salt or sodium salt in a liquid solvent to form an electrolyte having a first salt concentration and subsequently removing a portion of the liquid solvent to increase the salt concentration to obtain a quasi-solid electrolyte having a second salt concentration that is higher than the first salt concentration and higher than 2.5M.

64. The method of claim 63, wherein the removing does not cause precipitation or crystallization of salts and the electrolyte is in a supersaturated state.

65. The method of claim 63, wherein the liquid solvent comprises a mixture of at least a first liquid solvent and a second liquid solvent and the first liquid solvent is more volatile than the second liquid solvent, and wherein the removing a portion of the liquid solvent comprises removing the first liquid solvent.

66. The method of claim 52, wherein the alkali metal cell is a lithium metal cell or a lithium ion cell and the active material is an anode active material selected from the group consisting of:

(a) Particles of lithium metal or lithium metal alloy;

(f) A prelithiated version thereof;

(g) Pre-lithiated graphene sheets; and

a combination thereof.

67. The method of claim 66, wherein said prelithiated graphene sheets are selected from the group consisting of pristine graphene, graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide, hydrogenated graphene, nitrogenated graphene, boron doped graphene, nitrogen doped graphene, physically or chemically activated or etched versions thereof, or prelithiated versions of combinations thereof.

68. The method of claim 52, wherein the alkali metal cell is sodiumA metal cell or a sodium ion cell and the active material is an anode active material containing an alkali intercalation compound selected from the group consisting of: petroleum coke, amorphous carbon, activated carbon, template carbon, hollow carbon nanowires, hollow carbon spheres, and niti ₂ (PO ₄ ) ₃ 、Na ₂ Ti ₃ O ₇ 、Na ₂ C ₈ H ₄ O ₄ 、Na _x TiO ₂ Carboxylate-based materials, C ₈ H ₆ O ₄ 、C ₈ H ₅ NaO ₄ 、C ₈ Na ₂ F ₄ 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 a combination thereof, wherein x = 0.2 to 1.0.

69. The method of claim 52, wherein 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;

f) A sodium salt;

g) Graphene sheets preloaded with sodium ions; and

a combination thereof.

70. The method of claim 52, wherein the alkali metal cell is a lithium metal cell or a lithium ion cell and the active material is a cathode active material comprising a lithium intercalation compound selected from the group consisting of: lithium cobalt oxide, doped lithium cobalt oxide, lithium nickel oxide, doped lithium nickel oxide, lithium manganese oxide, doped lithium manganese oxide, lithium vanadium oxide, doped lithium vanadium oxide, lithium iron phosphate, lithium vanadium phosphate, lithium manganese phosphate, metal sulfides, and combinations thereof.

71. The method of claim 52, wherein the electrolyte is selected from the group consisting of an aqueous liquid, an organic liquid, an ionic liquid, or a mixture of an organic liquid and an ionic liquid.

72. The method of claim 52, wherein the alkali metal cell is a lithium metal cell or a lithium ion cell and the active material is a cathode active material containing a lithium intercalation compound or a lithium-absorbing compound selected from the group consisting of: an inorganic material, an organic material, or a combination thereof.

73. The method of claim 72, wherein the active material is a cathode active material comprising a lithium intercalation compound or a lithium-absorbing compound selected from the group consisting of: polymeric materials, metal oxides, metal phosphates, metal sulfides, or combinations thereof.

74. The method of claim 73, wherein the metal oxide, the metal phosphate, the metal sulfide is selected from the group consisting of lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium vanadium oxide, lithium iron phosphate, lithium manganese phosphate, lithium vanadium phosphate, transition metal sulfide, or a combination thereof.

75. The method of claim 72, wherein the inorganic material is selected from sulfur, lithium polysulfide, transition metal dichalcogenide, transition metal trichalcogenide, or a combination thereof.

76. The method of claim 72, wherein the inorganic material is selected from the group consisting of TiS ₂ 、TaS ₂ 、MoS ₂ 、NbSe ₃ 、MnO ₂ 、CoO ₂ Iron oxide, vanadium oxide, or a combination thereof.

77. The method of claim 73, wherein the metal oxide comprises a vanadium oxide selected from the group consisting of: VO (VO) ₂ 、Li _x VO ₂ 、V ₂ O ₅ 、Li _x V ₂ O ₅ 、V ₃ O ₈ 、Li _x V ₃ O ₈ 、Li _x V ₃ O ₇ 、V ₄ O ₉ 、Li _x V ₄ O ₉ 、V ₆ O ₁₃ 、Li _x V ₆ O ₁₃ A doping profile thereof, derivatives thereof, and combinations thereof, 0.1<x<5。

78. The method of claim 73, wherein the metal oxide, the metal phosphate, the metal sulfide are selected from the group consisting of layered compound LiMO ₂ Spinel-type compound LiM ₂ O ₄ Olivine-type compound LiMPO ₄ Silicate compound Li ₂ MSiO ₄ Hydroxy phosphorus lithium iron stone compound LiMPO ₄ F. Borate compound LiMBO ₃ Or combinations thereof, wherein M is a transition metal or a mixture of transition metals.

79. The method of claim 72, wherein the inorganic material is selected from the group consisting of: (a) bismuth selenide or bismuth telluride, (b) a transition metal di-or tri-chalcogenide, (c) a niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, cobalt, manganese, iron, or nickel selenide, or telluride; (d) boron nitride, or (e) combinations thereof.

80. The method of claim 72, wherein the organic material is selected from the group consisting of poly (anthraquinone sulfide) (PAQS), 3,4,9, 10-peryleneTetracarboxylic dianhydride (PTCDA), pyrene-4, 5,9, 10-tetraketone (PYT), quinone (triazene), tetracyanoquinone-dimethane (TCNQ), tetracyanoethylene (TCNE), 2,3,6,7,10, 11-Hexamethoxytriphenylene (HMTP), poly (5-amino-1, 4-dihydroxyanthraquinone) (PADAQ), phosphazene disulfide polymer ([ (NPS) ₂ ) ₃ ]n), lithiated 1,4,5, 8-naphthalene tetralin formaldehyde polymers, hexaazabinaphthyl (HATN), hexaazatriphenylene hexanitrile (HAT (CN) ₆ ) 5-benzylidenyl hydantoin, isatin lithium salt, pyromellitic diimide lithium salt, tetrahydroxy-p-benzoquinone derivative (THQLi) ₄ ) N, N ' -diphenyl-2, 3,5, 6-tetratone piperazine (PHP), N ' -diallyl-2, 3,5, 6-tetratone piperazine (AP), N ' -dipropyl-2, 3,5, 6-tetratone piperazine (PRP), 1, 4-benzoquinone, 5,7,12,14-Pentacene Tetratone (PT), 5-amino-2, 3-dihydro-1, 4-dihydroxyanthraquinone (ADDAQ), 5-amino-1, 4-dihydroxyanthraquinone (ADAQ), quinine calixarene, li ₄ C ₆ O ₆ 、Li ₂ C ₆ O ₆ 、Li ₆ C ₆ O ₆ Or a combination thereof.

81. The method of claim 80, wherein the organic material is selected from a thioether polymer selected from poly [ methane trinitrotoluene-tetra (thiomethylene) ] (PMTTM), poly (2, 4-dithiopentene) (PDTP), a polymer comprising poly (ethylene-1, 2-tetrathiol) (PETT) as a backbone thioether polymer, a side chain thioether polymer having a backbone consisting of conjugated aromatic moieties and having thioether side chains as side chains, poly (2-phenyl-1, 3-dithiolane) (PPDT), poly (1, 4-bis (1, 3-dithiolane-2-yl) benzene) (PDDTB), poly (tetrahydrobenzodithiophene) (PTHBDT), poly [1,2,4, 5-tetra (propylthio) benzene ] (PTKPTB), or poly [3,4 (ethylenedithio) thiophene ] (PEDTT).

82. The method of claim 72, wherein the organic material comprises a phthalocyanine compound selected from the group consisting of: copper phthalocyanine, zinc phthalocyanine, tin phthalocyanine, iron phthalocyanine, lead phthalocyanine, nickel phthalocyanine, vanadyl phthalocyanine, chromium fluoride phthalocyanine, magnesium phthalocyanine, manganese phthalocyanine, dilithium phthalocyanine, aluminum phthalocyanine chloride, cadmium phthalocyanine, gallium phthalocyanine chloride, cobalt phthalocyanine, silver phthalocyanine, metal-free phthalocyanine, chemical derivatives thereof, or combinations thereof.

83. The method of claim 72, wherein the lithium intercalation compound or lithium-absorbing compound is selected from a metal carbide, a metal nitride, a metal boride, a metal dichalcogenide, or a combination thereof.

84. The method of claim 72, wherein the lithium intercalation compound or lithium-absorbing compound is selected from an oxide, sulfide, selenide, or telluride of niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, vanadium, chromium, cobalt, manganese, iron, or nickel in the form of nanowires, nanoplates, nanoribbons, or nanoplatelets.

85. The method of claim 72, wherein the lithium intercalation compound or lithium-absorbing compound is selected from nano-discs, nano-coatings, or nano-sheets of an inorganic material selected from: (a) bismuth selenide or bismuth telluride, (b) a transition metal di-or tri-chalcogenide, (c) a niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, cobalt, manganese, iron, or nickel selenide, or telluride; (d) boron nitride, or (e) a combination thereof; wherein the nanoplate, the nanocoating, or the nanoplate has a thickness of less than 100 nm.

86. The method of claim 72, wherein the lithium intercalation compound or lithium-absorbing compound comprises a nanoplate, nanocoating, or nanoplate of a lithium intercalation compound selected from: (i) bismuth selenide or bismuth telluride, (ii) transition metal dichalcogenides or trichalcogenide, (iii) niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, cobalt, manganese, iron, or nickel selenide, or telluride; (iv) Boron nitride, or (v) a combination thereof, wherein the nanoplate, the nanocoating, or the nanoplatelets have a thickness of less than 100 nm.

87. The method of claim 52, wherein the alkali metal cell is a sodium metal cell or a sodium ion cell and the active material is a cathode active material containing a sodium intercalation compound or sodium absorbing compound selected from the group consisting of: an inorganic material, an organic material, or a combination thereof.

88. The method of claim 87, wherein the active material is a cathode active material comprising a sodium intercalation compound or sodium absorbing compound selected from the group consisting of: polymeric materials, metal oxides, metal phosphates, metal sulfides, or combinations thereof.

89. The method of claim 88, wherein the metal oxide, the metal phosphate, the metal sulfide is selected from sodium cobalt oxide, sodium nickel oxide, sodium manganese oxide, sodium vanadium oxide, sodium/potassium transition metal oxide, sodium iron phosphate, sodium manganese phosphate, sodium potassium manganese phosphate, sodium vanadium phosphate, potassium transition metal sulfide, or a combination thereof.

90. The method of claim 87, wherein the inorganic material is selected from sulfur, lithium polysulfide, transition metal dichalcogenide, transition metal trichalcogenide, or a combination thereof.

91. The method of claim 87, wherein the inorganic material is selected from TiS ₂ 、TaS ₂ 、MoS ₂ 、NbSe ₃ 、MnO ₂ 、CoO ₂ Iron oxide, vanadium oxide, or a combination thereof.

92. The method of claim 52, wherein the alkali metal cell is a sodium metal cell or a sodium ion cell and the active material is a cathode active material comprising a sodium intercalation compound selected from the group consisting of: naFePO ₄ 、Na _(1-x) K _x PO ₄ 、Na _0.7 FePO ₄ 、Na _1.5 VOPO ₄ F _0.5 、Na ₃ V ₂ (PO ₄ ) ₃ 、Na ₃ V ₂ (PO ₄ ) ₂ F ₃ 、Na ₂ FePO ₄ F、NaFeF ₃ 、NaVPO ₄ F、NaV ₆ O ₁₅ 、Na _x VO ₂ 、Na _0.33 V ₂ O ₅ 、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) MnO ₂ 、Na _0.44 MnO ₂ 、Na _0.44 MnO ₂ /C、Na ₄ Mn ₉ O ₁₈ 、NaFe ₂ Mn(PO ₄ ) ₃ 、Na ₂ Ti ₃ O ₇ 、Ni _1/3 Mn _1/3 Co _1/3 O ₂ 、Cu _0.56 Ni _0.44 HCF、NiHCF、NaCrO ₂ 、Na ₃ Ti ₂ (PO ₄ ) ₃ 、NiCo ₂ O ₄ 、Ni ₃ S ₂ /FeS ₂ 、Sb ₂ O ₄ 、Na ₄ Fe(CN) ₆ /C、NaV _1-x Cr _x PO ₄ F、Se _z S _y Se, dawsonite, or a combination thereof, wherein x is from 0.1 to 1.0, y/z = 0.01 to 100.