Patent Application
20240234726
The present disclosure relates to high capacity lithium ion anodes, cells, and batteries with high capacity lithium ion anodes with ternary materials: graphite-silicon-lithium as well as methods of forming these anodes, cells, or batteries. These anodes and cells and batteries containing them may exhibit high capacity as compared to similar anodes without modifications of the present disclosure.
Lithium batteries are widely used in consumer electronics due to their relatively high energy density. Rechargeable batteries are also referred to as secondary batteries, and lithium ion batteries are typically secondary batteries. Lithium ion secondary batteries generally have a negative electrode (anode) material that intercalates lithium and a positive electrode (cathode) material, such a lithium cobalt oxide, LiMn2O4, having a spinel structure, and LiFePO4, having an olivine structure, that intercalates and de-intercalates lithium while generally maintaining its crystal structure.
In conventional lithium ion batteries, the cathode material is the source of lithium available for electrochemical reaction. However, during the first charge-discharge cycle of the battery, a portion of the lithium available for electrochemical reaction forms a solid electrolyte interphase (SEI) layer on the anode, resulting in irreversible loss of this lithium and, consequently, a permanent decrease in the capacity of the battery. Furthermore, as the battery continues to cycle, electrolyte reaction and degradation often leads to thickening of the SEI layer and even more loss of available lithium and battery capacity.
The present disclosure provides a high capacity lithium ion anode comprising: an anode active material-containing layer having an electrolyte-facing side and a current collector-facing side, the anode active material-containing layer comprising: a graphite anode active material; a silicon or silicon compound active material; and a lithium reservoir; and an anode current collector.
In more specific embodiments, which may be combined with one another and with any other aspects of the present disclosure:
The present disclosure provides high capacity lithium ion cell comprising: any high capacity anode a described above or otherwise herein; a cathode comprising a cathode active material; and an electrolyte.
The present disclosure provides a battery comprising: at least one lithium ion cell as described above or otherwise herein; and a casing.
In more specific embodiments, which may be combined with any other aspects of the present disclosure: the battery is a cylindrical cell, a pouch cell, or a prismatic cell.
The present disclosure provides a battery module or pack, such as an electric vehicle battery comprising: at least one battery as described above or otherwise herein; a positive connector; a negative connector; and a housing.
In more specific embodiments, which may be combined with any other aspects of the present disclosure: the vehicle battery further comprises safety equipment, control equipment, or any combinations thereof.
The disclosure may be better understood through reference to the following figures, which are not to scale, which depict embodiments of the present disclosure, and in which:
The present disclosure relates to high capacity lithium ion anodes, cells, and batteries with high capacity lithium ion anodes as well as methods of forming these anodes, cells, or batteries. These high capacity lithium ion anodes generally include a graphite-silicon composition as the anode active material along with a lithium reservoir. The lithium reservoir, in various embodiments, may be lithium metal present in the anode, but not intercalated in the graphite-silicon composition, such as lithium particles or foil, or a lithium salt present in the anode as either free lithium salt or coated on the graphite-silicon composition, or any combinations thereof. It will be understood by one of skill in the art that these initial anode structures exist prior to cell or battery assembly and/or prior to cycling, e.g. in an uncycled cell or battery assembly.
As used herein following terms are ascribed the following meanings:
Chemical abbreviations are employed as is typical in the art. For example, a lithium ion may be designated as Li+ and an electron may be designated as e−. Weight % may be abbreviated as “wt %.”
A “cathode” (which may also be referred to as a “positive electrode”) is the electrode to which, during discharge of a lithium ion electrochemical cell, electrons flow and combine with lithium ion (typically in the context of a metal oxide insertion or de-insertion g the lithium ion). During charge of the electrochemical cell, electrons flow from the cathode and lithium ions are also released from the cathode.
A “cathode active material” is a chemical that undergoes electrochemical reaction in the cathode to exchange lithium ions and electrons with other components of the electrochemical cell.
A “bipolar cathode” is a cathode including two different layers that differ in their cathode active material compositions and, thus, also in their energy density and power density. In the simplest version of a bipolar cathode, a first layer contains a first cathode active material and the second layer contains a second cathode active material, which differs in chemical composition and at least one electrochemical property from the first cathode active material. “Bipolar cathode” does not denote a conventional bipolar battery stack configuration.
An “anode” (which may also be referred to as a “negative electrode”) is the electrode from which, during discharge of a lithium ion electrochemical cell, electrons flow and from which lithium ions are released. During charge of the electrochemical cell, electrons flow to the anode, where they combine with lithium ion, often to form lithium metal (Li).
An “anode active material” is a chemical that undergoes electrochemical reaction in the anode to exchange lithium ions and electrons with other components of the electrochemical cell, or upon which lithium metal may be plated or removed as lithium ions and electrons are separated and recombined by the electrochemical reaction.
A “current collector” is a component of the cathode or anode that exchanges electrons directly or indirectly with the active material to allow the electrochemical reaction to proceed.
An “electrolyte” is a substance that can exchange lithium ions with the cathode and anode. Although many examples in the present specification relate to liquid electrolytes, suitable non-liquid electrolytes, such as gel or solid electrolytes, may also be used in electrochemical cells encompassed by the present disclosure.
A “cell” or “electrochemical cell” is a basic physical unit in which a complete electrochemical reaction may occur if the cell is electrically connected to an external energy sink or energy source. An electrochemical cell includes a cathode, and anode, and an electrolyte. Unless the electrolyte forms an electrically non-conductive barrier between the anode and cathode, the electrochemical cell also contains a separator that forms an electrically non-conductive barrier between the anode and cathode. An electrochemical cell also includes a container that maintains the electrochemical cell as a physical unit, such as by containing a liquid electrolyte, excluding air or water from the cell, or protecting the cell components from physical damage.
A “battery” is a more complex physical unit that includes at least one electrochemical cell combined with at least one other component not a part of the electrochemical cell, such as a housing or a second or more electrochemical cells. A battery may also include other components, such as vents, air circulation systems, fire suppression systems, electrical conductors, such as wiring or bars, identification components, and even a processor and associated memory, which may for example, assess battery status and control battery functions.
“Uncycled” refers to a cell or battery that has never been charged and discharged or to an anode or cathode or an anode active material or cathode active material that has never been charged and discharged in a cell or battery.
“Hard carbon” is a solid form of carbon that cannot be converted to graphite by heat-treatment at temperatures up to 3000° C. and may also be referred to as “non-graphitizing carbon” as a result. Hard carbon may be formed by heating a suitable carbon-based precursor to 1000° C. in the absence of oxygen.
Unless otherwise specified, the term “including” is used in the expansive sense and means “not limited to.” Likewise, “or” is used expansively and means both one of the listed options and combination of more than one of the listed options (i.e. and/or). “A” “an,” and “the” include more than one. “About,” as used herein, means within a variation of 1%.
Numerical designations followed by a and b indicate similar components that may collectively be referred to by the numeral only.
All lists items disclosed herein should be interpreted as including any combinations thereof unless otherwise specified.
All bounded and unbounded ranges recited herein should be interpreted as including both all values between the endpoint values (or above or below the endpoint value, as the case may be, for unbounded ranges) and the endpoint values. The terms “in a range from” and “between” both include endpoint values.
Referring now to
Cathode 20 includes at least one cathode active material-containing layer 30 that contains at least one cathode active material 50. Cathode 20 further includes cathode current collector 40.
Anode 60 includes anode active material-containing layer 70 that contains anode active materials 90a (graphite) and 90b (silicon or silicon compound). Anode 60 also includes anode current collector 80.
Electrolyte 100 contains lithium ions 120. In some embodiments, not shown, the electrochemical cell 10 includes a solid electrolyte 100. Solid electrolyte 100 may include a dried or crosslinked form of the polymer matrix. In other embodiments, such as those depicted in
Separator 110 electrically insulates cathode 20 from anode 60 within electrochemical cell 10. Separator 110 allows at least lithium ions 120 to pass through it. In some embodiments, the separator 110 includes polyethylene, polypropylene, a ceramic-coated polymer composite, or any combinations thereof. In more specific embodiments, the separator is a polyethylene-polypropylene-polyethylene tri-layer membrane.
In some embodiments, the separator 110 further includes an electrically insulative material, such as glass. In a specific embodiment, the separator 100 may include glass fibers, particularly glass fibers formed into a porous mat.
In some embodiments, the separator 110 is coated on one or both sides with a ceramic material In more specific embodiments, the ceramic material includes oxide ceramic, sulfide, Al2O3, Al2O3—SiO2, or any combinations thereof.
Electrochemical cell 10, when connected to electrically conductive external circuit 130, allows electrons 150 to pass through external circuit 130 from the anode to the cathode or vice versa.
In the example depicted in
The voltage of any electrochemical cell according to the present disclosure is the difference between the half-cell potentials at the cathode and the anode, and the cathode active materials and anode active material(s) may be chosen accordingly. The electrolyte may be chosen to avoid or decrease the amount of degradation at the cell voltage.
Anode 60, as depicted in
In some embodiments, the anode active material may further comprise at least one of the following in addition to or in place of graphite or silicon: natural graphite, synthetic graphite, hard carbon, mesophase carbon, appropriate carbon blacks, coke, fullerenes, lithium metal, lithium powder, niobium titanium oxide (TNO) niobium pentoxide, intermetallic alloy, silicon alloy, tin alloy, silicon oxide, titanium oxide, tin oxide, lithium titanium oxide, silicon-functionalized graphene, silicon-functionalized graphite, other silicon-functionalized carbon, amorphous silicon, silicon nanotube, silicon compound, SiOx, in which x≤2 or x<2, graphene, carbon nanotube, including a single-walled carbon nanotube, hard carbon, or hard carbon and amorphous silicon or silicon nanotubes, or any combinations thereof. In some embodiments, the anode active material 90, even with the above additions or substitutions still contains at least one of graphite or silicon.
In some embodiments, the graphite anode active material 90a may be present in a weight % (wt %) as compared to total anode active material weight between about 5 wt % and about 99 wt %, including ranges therein with endpoints of about 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 92, 95, 98 wt %. In some more specific embodiments, the graphite anode active material 90a may be present in a weight % (wt %) as compared to total anode active material weight between about 92 wt % and 99 wt %, including ranges therein with endpoints of about 92, 93, 94, 95, 96, 97, 98 wt %. %. In some more specific embodiments, the graphite anode active material 90a may be present in a weight % (wt %) as compared to total anode active material weight between about 85 wt % and 99 wt %, including ranges therein with endpoints of about 86, 87, 88, 90, 91, 92, 93, 94, 95, 96, 97, 98 wt %.
In some embodiments, the graphite anode active material 90a may be a synthetic graphite, a natural graphite, or a combination thereof. If the graphite anode active material 90a is a combination of synthetic graphite and natural graphite, the synthetic graphite may be present in a weight % (wt %) as compared to total graphite anode active material 90a weight between about 5 wt % and about 95 wt %, including ranges therein with endpoints of about 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90 wt %.
In some embodiments, the silicon anode active material 90b may be elemental silicon (also referred to herein as simply “silicon”), a silicon compound, particularly SiOx in which x<2, or in which x≤2, or any combinations thereof. If the silicon anode active material 90b is a combination of silicon and a silicon compound, the silicon may be present in a weight % (wt %) as compared to total silicon anode active material 90b weight between about 5 wt % and about 95 wt %, including ranges therein with endpoints of about 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90 wt %. If the silicon anode active material 90b contains a silicon compound, SiOx i) in which x<2, or ii) in which x≤2 may be present in a weight % (wt %) as compared to total SiOx anode active material 90b weight between about 5 wt % and about 95 wt %, including ranges therein with endpoints of about 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90 wt %. If specific embodiments, the silicon compound may be SiOx in which x<2.
In some embodiments, the following reaction may occur with silicon in the anode 60: (SiO+Li→Li2O+Li×Si LizO) (ICL).
In some embodiments, the silicon may be present in the form of particles. In a more specific embodiment, the particles are nanoparticles and may have an average longest dimension (such as diameter for spherical particles, or length for cylindrical particles) that is 900 nm, 750 nm, 500 nm, 250 nm, 100 nm, 50 nm, or 10 nm or less, or in a range of 0.1 nm to 900 nm, 0.1 nm to 750 nm, 0.1 nm to 500 nm, 0.1 nm to 250 nm, 0.1 nm to 100 nm, 0.1 nm to 50 nm, or 0.1 nm to 10 nm. In some embodiments, the silicon in the anode may include between 5% and 50% silicon nanoparticles by weight. Anodes containing silicon nanoparticles may have lower volume expansion during cycling than anodes containing silicon microparticles.
The anode active material-containing layer 70 additional includes a lithium reservoir, which contains lithium metal 160 or lithium salt 170 not intercalated in the graphite or silicon anode active materials 90 in an uncycled electrochemical cell 10. The lithium reservoir may be located relative to anode active material-containing layer 70 in a variety of ways. For example, the lithium reservoir may be located primarily at the electrolyte-facing portion of the anode active material-containing layer 70, as illustrated in
In some embodiment, prior to cycling the anode active material-containing layer 70 may include up to 20% lithium metal by weight, up to 15% lithium metal by weight, up to 10% lithium metal by weight, lithium metal in a range of 1% to 20% by weight, 1% to 15% by weight, 1% to 10% by weight, 5% to 20% by weight, 5% to 15% by weight, or 5% to 10% by weight.
Anode active material-containing layer 70 may also be structured in a variety of ways. For example, it may be formed from graphite particles and silicon or silicon compound particles. These particles may be mixed as illustrated in
In some embodiments, the graphite particles may be of a uniform diameter, such that 90% of the particles have a diameter within 10% of the average particle diameter. In other embodiments, the graphite particles may be of two distinct, uniform sizes. For example, the graphite particles may have a first uniform size with an average diameter at least 1.5, 2, 2.5, 3, 5, 10, or 20 times the average diameter of graphite particles of the second uniform size.
In some embodiments, the silicon or silicon compound particles may be of uniform diameter, such that 90% of the particles have a diameter with 10% of the average particle diameter. In other embodiments, the silicon or silicon compound particles may be of two distinct, uniform sizes. For example, the silicon or silicon compound particles may have a first uniform size with an average diameter at least 1.5, 2, 2.5, 3, 5, 10, or 20 times the average diameter of silicon or silicon compound particles of the second uniform size.
More specifically,
Anode active material-containing layer 70 may also be structured in the form of graphite and silicon or silicon compound layers, which may be continuous sheets of material as illustrated in
In embodiments containing lithium metal particles, these particles may include a coating that inhibits reaction of lithium metal with oxygen or water.
Although the figures illustrate embodiments with only single layers of lithium reservoir, in some embodiments, multiple layers may also be present in the anode 60. In addition, although the figures illustrate embodiments with only single graphite or silicon or silicon compound layers, multiple layers may be present in the anode 60.
In some embodiments, the lithium reservoir is in the form of a lithium salt 170. As illustrated in
The lithium salt 170 may, in particular embodiments, be lithium bis(trifluoromethanesulfonyl)imide (LIFSI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), lithium tetrafluoroborate (LiBF4), lithium 4,5-dicyano-2-(trifluoromethyl)imidazole (LiTDI), lithium hexafluorophosphate (LiPF6), lithium iodide (LiI), or any mixtures or combinations thereof, particularly 1-Butyl-3-methylimidazolium bis(trifluoromethanesulfonyl) imide combined with LiTFSI. The lithium salt 170 may further include compounds to enhance electrode stability by impeding the reaction of lithium with oxygen, particularly under normal atmosphere, such as an organic polymer coating.
Suitable additional materials that may be present in anode 60 include polymer binders, conductivity enhancers and combinations thereof.
Suitable conductivity enhancers include carbon fibers, such as vapor grown carbon fibers (VGCF), carbon nanorods, graphite, or carbon blacks, such as acetylene black, Denka black, Keitjen black, hard carbon, silver/gold nano-wires or particles, or any combinations thereof.
In some embodiments, the anode active material-containing layer 70 may include 5 wt % or less conductivity enhancer. More specifically, the anode active material-containing layer 70 may include between about 1 wt % and about 5 wt %, between about 2 wt % and about 5 wt %, about 1 wt % and about 4 wt %, about 2 wt % and about 4 wt %, or about 3 wt % and about 4 wt % conductivity enhancer.
Suitable polymer binders include binders that adhere the anode active materials or lithium reservoir to other components of the anode 60, such as the other layers or particles, as the case may be, or the current collector 80. In some embodiments, the polymer binder may include polyvinylidine fluoride (PVDF), polyethylene oxide, polyethylene, polypropylene, polytetrafluoroethylene, polyacrylates, ethylene-(propylene-diene monomer) copolymer (EPDM), water soluble binder, such as synthetic rubber, particularly styrene-butadiene rubber/carboxyl methyl-cellulose (SBR/CMC), sodium alginate, or sodium acrylate, conducting polymers, and any mixtures and copolymers thereof. Conducting polymers may include poly(3,4)ethylene dioxane thiophene (PEDOT), poly-styrene sulfonate (PSS), polyvinyl alcohol (PVA), polyethylene glycol (PEG), polyethylene oxide (PEO), polymethyl methacrylate (PMMA), and any mixtures and copolymers thereof.
In some embodiments, the anode active material-containing layer 70 may include 5 wt % or less polymer binder. More specifically, the anode active material-containing layer 70 may include between about 1 wt % and about 5 wt %, between about 2 wt % and about 5 wt %, about 1 wt % and about 4 wt %, about 2 wt % and about 4 wt %, or about 3 wt % and about 4 wt % polymer binder.
In some embodiments, the anode active material-containing layer 70 may include 5 wt % or less, 3 wt % or less, between 0.5 and 5 wt %, between 1 and 5 wt %, between 0.5 and 3 wt %, or between 1 and 3 wt % lithium metal phosphate cathode material, with may be the same as or different from the cathode material in the cell.
In some embodiments, a third, fourth, or more anode active material may also be present.
Anode 60 may include an anode current collector 80, which may be any suitable electrically conductive material, such as a metal foil, a metal grid, a metal screen, metal foam, or expanded metal (which is a metal grid or metal screen that has a thickness sufficient to allow a substantial amount of cathode active material to collect within it) or at least one graphene layer, typically a plurality of graphene layers. In some embodiments, anode current collector 80 may include Ni, Ti, C, Cu, stainless steel, or any combinations thereof. In a specific embodiment, the anode current collector 80 is copper, more specifically copper foil. In some embodiments, if the current collector includes or is a metal, it may further include a conductive and corrosion-resistant coating, such as TiN.
In some embodiments, the anode active material-containing layer 70 has a thickness of between about 2 microns and about 8 microns, about 2 microns and about 6 microns, 5 about 2 microns and about 4 microns, about 4 microns and about 8 microns, about 4 microns and about 6 microns, about 6 microns and about 8 microns, or about 2 microns and about 100 microns.
In some embodiments, not shown, the anode 60 may have an anode active material-containing layer 70 on both sides of the current collector 80. In a more specific embodiment, such an anode 60 has a thickness of between about 2 microns and about 1000 microns, about 2 microns and about 8 microns, about 2 microns and about 6 microns, about 2 microns and about 4 microns, about 4 microns and about 8 microns, about 4 microns and about 6 microns, about 6 microns and about 8 microns, about 2 microns and about 500 microns, or about 2 microns and about 100 microns. In some embodiments, the anode layer 70 has a total anode active material 90 loading of between about 1 mg/cm2 and about 100 mg/cm2 total or per side, if both sides have cathode active material.
In some embodiments, the anode layer 70 has a density of between about 0.5 g/mL and about 3 g/mL, about 0.5 g/mL and about 2.5 g/mL, about 0.5 g/mL and about 2 g/mL, about 1 g/mL and about 3 g/mL, about 1 g/mL and about 2.5 g/mL, about 1 g/mL and about 2 g/mL, about 1 g/mL and about 100 g/mL, more specifically between about 1 g/mL and about 75 g/mL, about 1 g/mL and about 50 g/mL, about 1 g/mL and about 25 g/mL, about 25 g/mL and about 100 g/mL, about 25 g/mL and about 75 g/mL, about 25 g/mL and about 50 g/mL, about 50 g/mL and about 100 g/mL, about 50 g/mL and about 75 g/mL, or about 75 g/mL and about 100 g/mL.
In some embodiments, the anode 60 or anode active material-containing layer 70 may exhibit a loss of lithium of less than 1% by weight, or in a range of 0.001% to 1% by weight after 100 cycles.
The cathode active material 50 may be any active material compatible with a graphite-silicon anode, or any combination of such active materials. In some embodiments the cathode active material 50 may be a lithium compound, such as a lithium metal oxide (LMO) or lithium metal phosphate (LMP).
The cathode active material may generally be present in a crystalline, and not amorphous, form. In particular, the lithium metal oxides may be those that exhibit a layered crystal structure, similar to that of lithium cobalt oxide, more particularly a rhombohedral lattice, hexagonal class crystal structure, such as that of space group R-3m. The lithium metal phosphates may be those that exhibit an orthorhombic crystal structure of space group Pnma, sometimes referred to as an olivine structure. Some cathode active materials may have spinel structure.
The cathode active material 50 may be in the form of particles, which may be nanoparticles, microparticles, or agglomerates. Particle size includes any coating on cathode active materials. Where multiple cathode active material are present, cathode active materials may have about the same particle size or different particle sizes and similarly may be agglomerated or non-agglomerated, or one particle type may be agglomerated while the other is not.
In specific embodiments, the cathode active may include lithium cobalt oxide (LiCoO2), lithium nickel aluminum oxide (LiNi/Al/O2), lithium nickel manganese cobalt oxide (LiNi/Mn/CoO2, also referred to as “NMC”), particularly in which Ni is present in at least 50 wt % of the total weight of Ni, Mn, and Co, lithium nickel cobalt aluminum oxide (LiNi/Co/AlO2, also referred to as “NCA”), lithium nickel manganese cobalt aluminum oxide (LiNi/Mn/Co/AlO2, also referred to as NMCA), lithium iron phosphate (also referred to as “LFP”), lithium manganese iron phosphate (also referred to as “LMFP”), lithium manganese nickel iron phosphate (also referred to as “LMNFP”), lithium iron cobalt phosphate (also referred to as “LFCP”), or lithium iron manganese cobalt phosphate (also referred to as “LFMCP”), in any combinations.
In specific embodiments, NMC contains Ni in an amount that is at least 50 wt % of the total weight of Ni, Mn, and Co.
In other specific embodiments, the cathode may include a combination of two or more NMCs that differ in their respective relative amounts of Ni, Mn, and Co.
In some embodiments, the cathode may contain one or a mixture of cathode active materials.
In some embodiments, the cathode, when in an uncycled state, also contains an unlithiated metal oxide, such as an unlithiated metal phosphate in addition to the lithiated materials. In some embodiments, the unlithiated metal oxide has the same chemical composition as the lithiated metal oxide, but without lithium (e.g. LiFePO4 and FePO4). In other embodiments, the unlithiated metal oxide has a different chemical composition than the lithiated metal oxide (e.g. LiFePO4 and MnFePO4 or LiMn0.2Fe0.8PO4 and Mn0.15Fe0.85PO4).
In more specific embodiments, Li may be present in the cathode active materials an amount between about 1 wt % and about 99 wt %, about 1 wt % and about 95 wt %, about 1 wt % and about 90 wt %, about 1 wt % and about 85 wt %, about 1 wt % and about 80 wt %, about 1 wt % and about 50 wt %, about 10 wt % and about 99 wt %, about 10 wt % and about 95 wt %, about 10 wt % and about 90 wt %, about 10 wt % and about 85 wt %, about 10 wt % and about 80 wt %, about 10 wt % and about 50 wt %, about 25 wt % and about 99 wt %, about 25 wt % and about 95 wt %, about 25 wt % and about 90 wt %, about 25 wt % and about 85 wt %, about 25 wt % and about 80 wt %, about 25 wt % and about 50 wt %, about 50 wt % and about 99 wt %, about 50 wt % and about 95 wt %, about 50 wt % and about 90 wt %, about 50 wt % and about 85 wt %, about 50 wt % and about 80 wt %, about 1 wt % and about 20 wt %, about 5 wt % and about 20 wt %, about 10 wt % and about 50 wt %, or about 15 wt % and about 20 wt %. In such embodiments, the anode may not contain lithium ion or lithium metal. In other embodiments, the anode may contain additional sources of Li to supplement the Li not contained in the unlithiated cathode.
In other embodiments the cathode may contain at least two distinct cathode active materials or mixtures of cathode active materials in separate cathode layers to form of a bipolar cathode.
Cathode active materials that contain manganese may suffer decreases in performance or failure due to dissolution of manganese through the cell, particularly during use. Non-lithiated metal phosphate in cathode active materials and cathode of the present disclosure may act as a stabilizing and balancing factor that decreases or prevents manganese dissolution during use of a cell.
In some embodiments, one or more, or all of the cathode active materials may not contain cobalt. In contrast to toxic cobalt, iron, manganese, and nickel are generally non-toxic and, even if released by damage to a battery, are very unlikely to be taken up by the body in harmful amounts. In addition, these cathode active materials may help prevent thermal runaway and resulting battery or cell damage and fires. However, embodiments in which one or more, or all of the cathode active materials do contain cobalt are also suitable for use in a cathode as disclosed herein.
In some embodiments, the NMC has the general chemical formula LiNi1-x-yMnxCoyO2, wherein 1−x−y, x, and y are each greater than 0, and 1−x−y is such that Ni is present in an amount of at least 50 wt % of the total weight of Ni, Mn, and Co, such as between 50 wt % and about 99 wt %, between 50 wt % and about 95 wt %, between 50 wt % and about 90 wt %, between 50 wt % and about 85 wt %, between about 50 wt % and about 80 wt %, between 50 wt % and about 75 wt %, between 50 wt % and about 70 wt %, between 50 wt % and about 65 wt %, between 50 wt % and about 60 wt %, or between 50 wt % and about 55 wt %. In some embodiments, 1−x−y is such that Ni is present in an amount of at least 80 wt % of the total weight of Ni, Mn, and Co, such as between 80 wt % and about 99 wt %, between 80 wt % and about 95 wt %, between 80 wt % and about 90 wt %, or between 80 wt % and about 85 wt %.
In some embodiments in which the NMC has the general chemical formula LiNi1-x-yMnxCoyO2, wherein x is such that Mn is present in an amount of up to 30 wt % of the total weight of the NMC. In more specific embodiments, Mn may be present in an amount of between about 1 wt % and 30 wt %, about 5 wt % % and 30 wt %, about 10 wt % and 30 wt % %, or about 20 wt % and 30 wt %.
In a more specific embodiment, the NMC has the chemical formula LiNi0.8CO0.1Mn0.1O2. In some embodiments, the NCA has the general chemical formula LiNi1-x-yCoxAlyO2, wherein 1−x−y, x, and y are each greater than 0. In specific embodiments, 0<x≤0.2, more specifically 0.01≤x≤0.2, 0.1≤x≤0.2 and 0<y≤0.2 more specifically 0.01≤y≤0.2, 0.1≤y≤0.2. In more specific embodiments, 0.6≤(1−x−y)≤0.99, more specifically, 0.6≤(1−x−y)≤0.9, 0.6≤(1−x−y)≤0.8, 0.6≤(1−x−y)≤0.7.
In some embodiments, the NCA has the general chemical formula LiNi1-x-yCoxAlyO2, and 1−x−y is such that Ni is present in an amount of at least 50 wt % of the total weight of Ni, Co, and Al, such as between 50 wt % and about 99 wt %, between 50 wt % and about 95 wt %, between 50 wt % and about 90 wt %, between 50 wt % and about 85 wt %, between about 50 wt % and about 80 wt %, between 50 wt % and about 75 wt %, between 50 wt % and about 70 wt %, between 50 wt % and about 65 wt %, between 50 wt % and about 60 wt %, or between 50 wt % and about 55 wt %. In some embodiments, 1−x−y is such that Ni is present in an amount of at least 80 wt % of the total weight of Ni, Co, and Al, such as between 80 wt % and about 99 wt %, between 80 wt % and about 95 wt %, between 80 wt % and about 90 wt %, or between 80 wt % and about 85 wt %.
In some embodiments, the NMCA has the general chemical formula LiNi1-x-y-zMnxCoyAlzO2, wherein 1−x−y−z, x, y, and z are each greater than 0. In specific embodiments, 0<x≤0.2, more specifically 0.01≤x≤0.2, 0.1≤x≤0.2, 0<y≤0.2 more specifically 0.01≤y≤0.2, 0.1≤y≤0.2, and 0<z≤0.2, more specifically 0.01≤z≤0.2, 0.1≤z≤0.2. In more specific embodiments, 0.4≤(1−x−y−z)≤0.99, more specifically, 0.4≤(1−x−y)≤0.9, 0.4≤(1−x−y)≤0.8, 0.4≤(1−x−y)≤0.7.
In some embodiments, the NMCA has the general chemical formula LiNi1-x-y-zMnxCoyAlzO2, wherein 1−x−y−z is such that Ni is present in an amount of at least 50 wt % of the total weight of Ni, Mn, Co, and Al, such as between 50 wt % and about 99 wt %, between 50 wt % and about 95 wt %, between 50 wt % and about 90 wt %, between 50 wt % and about 85 wt %, between about 50 wt % and about 80 wt %, between 50 wt % and about 75 wt %, between 50 wt % and about 70 wt %, between 50 wt % and about 65 wt %, between 50 wt % and about 60 wt %, or between 50 wt % and about 55 wt %. In some embodiments, 1−x−y−z is such that Ni is present in an amount of at least 80 wt % of the total weight of Ni, Mn, Co, and Al, such as between 80 wt % and about 99 wt %, between 80 wt % and about 95 wt %, between 80 wt % and about 90 wt %, or between 80 wt % and about 85 wt %.
In some embodiments, the LFP has the general chemical formula LiFePO4.
Lithium metal phosphate cathode active materials 50a may include LMFP. In some embodiments, these materials have the general chemical formula LiMnxFe1-xPO4, wherein 0.01≤x≤0.95.
In more specific embodiments, 0.01≤x≤0.5, 0.01≤x≤0.4, 0.01≤x≤0.3, 0.01≤x≤0.25, 0.01≤x≤0.2, 0.01≤x≤0.15, 0.01≤x≤0.10, 0.01≤x≤0.05, 0.05≤x≤0.95, 0.05≤x≤0.5, 0.05≤x≤0.4, 0.05≤x≤0.3, 0.05≤x≤0.25, 0.05≤x≤0.2, 0.05≤x≤0.15, 0.05≤x≤0.1, 0.1≤x≤0.95, 0.1≤x≤0.5, 0.1≤x≤0.4, 0.1≤x≤0.3, 0.1≤x≤0.25, 0.1≤x≤0.2, 0.1≤x≤0.15, 0.15≤x≤0.95, 0.15≤x≤0.5, 0.15≤x≤0.4, 0.15≤x≤0.3, 0.15≤x≤0.25, 0.15≤x≤0.2, 0.2≤x≤0.95, 0.2≤x≤0.5, 0.2≤x≤0.4, 0.2≤x≤0.3, or 0.2≤x≤0.25. In a more specific embodiment, the materials have the chemical formula LiMn0.2Fe0.8PO4.
In other more specific embodiments, 0.5≤x≤0.95, 0.5≤x≤0.8, 0.5≤x≤0.7, 0.5≤x≤0.6, 0.6≤x≤0.95, 0.6≤x≤0.8, 0.6≤x≤0.7, 0.7≤x≤0.95, 0.7≤x≤0.8, or 0.8≤x≤0.95. In a more specific embodiment, the materials have the chemical formula LiMn0.5Fe0.5PO4, and LiMn0.8Fe0.2PO4.
Lithium metal phosphate cathode active materials 50a may include LMNFP. In some embodiments, these materials have the general chemical formula LiMnxNiyFe1-(x+y)PO4, in which 0<x<1, 0<y<1 and x+y<1. In some specific embodiments:
In any embodiments, particularly those of a), b), or c) the ratio of x:y may be in a range between 5:1 and 1:5, more particularly between 5:1 and 1:3, 5:1 and 1:1, 5:1 and 3:1, 3:1 and 1:5, 3:1 and 1:3, 3:1 and 1:1, 1:1 and 1:5, 1:1 and 1:3, 1:3 and 1:5.
In more specific embodiments, the ratio of x:y may be in a range between 1:2 and 1:5, more particularly between 1:2 and 1:4, 1:2 and 1:3, 1:3 and 1:5, 1:3 and 1:4, or 1:4 and 1:5.
In other more specific embodiments, the ratio of x:y may be in a range between 5:1 and 1:2, more particularly between 5:1 and 1:1, 4:1 and 1:2, 4:1 and 1:1, 3:1 and 1:2, 3:1 and 1:1, 2:1 and 1:2, and 2:1 and 1:1.
In a more specific embodiment, the materials have the chemical formula LiMn0.04Ni0.16Fe0.8PO4.
In some embodiments, LFCP has the general chemical formula LiFe1−xCoxPO4, in which 0<x<1. In some specific embodiments, x≥0.05, x≥0.1, x≥0.2, x≥0.3, x≥0.4, x≥0.5, x≥0.6, x≥0.7, x≥0.8, x≥0.9, or x≥0.95.
In some embodiments, LFMCP has the general chemical formula LiFe1−(x+y)MnxCoyPO4, in which 0<x<1, 0<y<1 and x+y<1. In some specific embodiments, a) 0<x≤0.5, more particularly 0.05≤x≤0.50, 0.05≤x≤0.25, 0.05≤x≤0.2, 0.05≤x≤0.15, 0.05≤x≤0.1, 0.1≤x≤0.5, 0.1≤x≤0.25, 0.1≤x≤0.2, or 0.1≤x≤0.15; b) 0<y≤0.95, more particularly 0.05≤y≤0.95, 0.05≤y≤0.9, 0.05≤y≤0.75, 0.05≤y≤0.5, 0.05≤y≤0.25, 0.05≤y≤0.1, 0.1≤y≤0.95, 0.1≤y≤0.9, 0.1≤y≤0.75, 0.1≤y≤0.5, or 0.1≤y≤0.25; or c) 0<x+y≤0.95, more particularly 0.05≤x+y≤0.95, 0.05≤x+y≤0.75, 0.05≤x+y≤0.5, 0.05≤x+y≤0.25, 0.05≤x+y≤0.1, 0.1≤x+y≤0.95, 0.1≤x+y≤0.9, 0.1≤x+y≤0.75, 0.1≤x+y≤0.5, or 0.1≤x+y≤0.25.
In any embodiments, particularly those of a), b), or c) the ratio of x:y may be in a range between 5:1 and 1:5, more particularly between 5:1 and 1:3, 5:1 and 1:1, 5:1 and 3:1, 3:1 and 1:5, 3:1 and 1:3, 3:1 and 1:1, 1:1 and 1:5, 1:1 and 1:3, 1:3 and 1:5.
In more specific embodiments, the ratio of x:y may be in a range between 1:2 and 1:5, more particularly between 1:2 and 1:4, 1:2 and 1:3, 1:3 and 1:5, 1:3 and 1:4, or 1:4 and 1:5.
In other more specific embodiments, the ratio of x:y may be in a range between 5:1 and 1:2, more particularly between 5:1 and 1:1, 4:1 and 1:2, 4:1 and 1:1, 3:1 and 1:2, 3:1 and 1:1, 2:1 and 1:2, and 2:1 and 1:1.
In a more specific embodiment, the materials have the chemical formula LiMn0.04Ni0.16Fe0.8PO4.
In some embodiments, lithium cobalt oxide, lithium nickel aluminum oxide, NMC, NCA, NMCA, LFP, LMFP, LMNFP, LFCP, or LFMCP may include additional elements included in their crystal structures. These additional elements may affect electrical conductivity and/or lithium ion intercalation of the cathode active material. Additional elements may have or be capable of existing in a charge state equal to that of the element replaced in the crystal structure. For example, iron may be replaced with another element that may exist in a 2+ or 3+ charge state. The additional element may be a transition metal also able to move from one charge to another during an electrochemical reaction, or if may be a fixed valence material, such as a fixed-valence 2+ metal in place of iron. Phosphorus may also be replaced, where present with sulfur or silicon. The amount of transition metal replaced by another metal may be 10%, 5%, 2%, 1%, 0.5%, or 0.1% or less, or in a range of 0.1% to 10%, 0.1% to 5%, 0.1% to 2%, 0.1% to 1%, 0.1% to 0.5%, 0.5% to 5%, 0.5% to 2%, 0.5% to 1%, 1% to 5%, 1% to 2%, or 2% to 5%.
In some embodiments, the lithium cobalt oxide, lithium nickel aluminum oxide, NMC, NCA, NMCA, LFP, LMFP, LMNFP, LFCP, or LFMCP. may be partially unlithiated when the cell 10 is uncycled. In specific embodiments, lithium cobalt oxide, lithium nickel aluminum oxide, NMC, NCA, NMCA, LFP, LMFP, LMNFP, LFCP, or LFMCP may and contain lithium in an amount up to 99%, up to 95%, up to 90%, up to 85%, up to 80%, up to 50%, or up to 20 wt % of the total weight of the lithium cobalt oxide, lithium nickel aluminum oxide, NMC, NCA, NMCA, LFP, LMFP, LMNFP, LFCP, or LFMCP. In more specific embodiments, Li may be present in the cathode active materials an amount between about 1 wt % and about 99 wt %, about 1 wt % and about 95 wt %, about 1 wt % and about 90 wt %, about 1 wt % and about 85 wt %, about 1 wt % and about 80 wt %, about 1 wt % and about 50 wt %, about 10 wt % and about 99 wt %, about 10 wt % and about 95 wt %, about 10 wt % and about 90 wt %, about 10 wt % and about 85 wt %, about 10 wt % and about 80 wt %, about 10 wt % and about 50 wt %, about 25 wt % and about 99 wt %, about 25 wt % and about 95 wt %, about 25 wt % and about 90 wt %, about 25 wt % and about 85 wt %, about 25 wt % and about 80 wt %, about 25 wt % and about 50 wt %, about 50 wt % and about 99 wt %, about 50 wt % and about 95 wt %, about 50 wt % and about 90 wt %, about 50 wt % and about 85 wt %, about 50 wt % and about 80 wt %, about 1 wt % and about 20 wt %, about 5 wt % and about 20 wt %, about 10 wt % and about 50 wt %, or about 15 wt % and about 20 wt %. In such embodiments, the anode may not contain lithium ion or lithium metal. This results in a cell in which all of the lithium cobalt oxide, lithium nickel aluminum oxide, NMC, NCA, NMCA, LFP, LMFP, LMNFP, LFCP, or LFMCP is normally not fully lithiated, even when the cell is fully discharged.
The lithium compound may include a halide, such as F, or the lithium compound material may be doped with an inorganic halide composition, such as an inorganic fluoride composition, such as a metal fluoride.
The cathode active material 50 may be coated, for example with an inorganic halide composition, such as an inorganic fluoride composition, such as a metal fluoride, or a conductivity enhancer, such as carbon.
In more specific embodiments, the metal fluorides may be LiF, ZnF2, AlF3, and any combinations thereof. AlF3 may be particularly useful due to its reasonable cost and low negative environmental impact.
In still other embodiments, the cathode active-material containing layer 30 may at least 90 wt % cathode active material 50 which, for purposes of this measurement, includes any coating or dopant. More specifically, the cathode layer 30 may include between about 90 wt % and about 99 wt %, about 90 wt % and about 98 wt %, about 90 wt % and about 97 wt %, about 90 wt % and about 96 wt %, or about 90 wt % and about 95 wt % cathode active material 50.
Cathode active-material containing layer 30 may contain additional materials, such as polymer binders and conductivity enhancers and combinations thereof.
Suitable conductivity enhancers include carbon fibers, such as vapor grown carbon fibers (VGCF), carbon nanorods, graphite, or carbon blacks, such as acetylene black, Denka black, Keitjen black, hard carbon, silver/gold nano-wires or particles, or any combinations thereof.
In some embodiments, the anode may include a conductivity enhancer, polymer binder, or other additive.
Suitable conductivity enhancers include carbon fibers, such as vapor grown carbon fibers (VGCF), carbon nanorods, graphite, or carbon blacks, such as acetylene black, Denka black, Keitjen black, hard carbon, silver/gold nano-wires or particles, or any combinations thereof.
In some embodiments, the polymer binder may include polyvinylidine fluoride (PVDF), polyethylene oxide, polyethylene, polypropylene, polytetrafluoroethylene, polyacrylates, ethylene-(propylene-diene monomer) copolymer (EPDM), water soluble binder, such as synthetic rubber, particularly styrene-butadiene rubber (SBR), styrene-butadiene rubber/carboxyl methyl-cellulose (SBR/CMC), sodium alginate, or sodium acrylate, silicone, conducting polymers, and any mixtures and copolymers thereof. Conducting polymers may include poly(3,4)ethylene dioxane thiophene (PEDOT), poly-styrene sulfonate (PSS), polyvinyl alcohol (PVA), polyethylene glycol (PEG), polyethylene oxide (PEO), polymethyl methacrylate (PMMA), and any mixtures and copolymers thereof.
In more specific embodiments, the polymer binder may have a molecular weight of about 200 atomic mass units (AMU) or more. More specifically, the polymer binder may have a molecular weight higher than 200 AMU.
In some embodiments, the cathode active-material containing layer 30 may include 5 wt % or less conductivity enhancer. More specifically, the cathode active-material containing layer 30 may include between about 1 wt % and about 5 wt %, between about 2 wt % and about 5 wt %, about 1 wt % and about 4 wt %, about 2 wt % and about 4 wt %, or about 3 wt % and about 4 wt % conductivity enhancer.
Suitable polymer binders include binders that adhere the cathode active material to other components of the cathode 20, such as the cathode current collector 40. In some embodiments, the polymer binder may include polyvinylidine fluoride (PVDF), polyethylene oxide, polyethylene, polypropylene, polytetrafluoroethylene, polyacrylates, ethylene-(propylene-diene monomer) copolymer (EPDM), water soluble binder, such as synthetic rubber, particularly styrene-butadiene rubber/carboxyl methyl-cellulose (SBR/CMC), sodium alginate, or sodium acrylate, and any mixtures and copolymers thereof.
In some embodiments, the cathode active-material containing layer 30 may include 6 wt % or less polymer binder. More specifically, the cathode active-material containing layer 30 may include between about 1 wt % and about 6 wt %, between about 2 wt % and about 6 wt %, about 1 wt % and about 5 wt %, about 2 wt % and about 5 wt %, or about 3 wt % and about 5 wt % polymer binder.
Cathode 20 also includes cathode current collector 40, which may be any suitable electrically conductive material, such as a metal foil, a metal grid, a metal screen, metal foam, or expanded metal (which is a metal grid or metal screen that has a thickness sufficient to allow a substantial amount of cathode active material to collect within it) or at least one graphene layer, typically a plurality of graphene layers. In some embodiments, cathode current collector 40 may include Al, Ni, Ti, C, stainless steel, or any combinations thereof. In a specific embodiment, the cathode current collector 40 is aluminum, more specifically aluminum foil. In some embodiments, if the current collector includes or is a metal, it may further include a conductive and corrosion-resistant coating, such as TiN.
In some embodiments, not depicted, cathode active-material containing layers 30 may be formed on both sides of the cathode current collector.
The electrolyte 100 may be a liquid, gel, or solid electrolyte.
The electrolyte 100 may include any electrolyte that does not substantially degrade at the cycling voltages of electrochemical cell 10.
Electrolyte 100 may include an ionic liquid, an organic liquid, or a combination thereof. If the ionic liquid or organic liquid does not supply lithium ion, then electrolyte 100 may include a lithium salt. In more specific embodiments, electrolyte 100 may also include a flame retardant.
In some embodiments, electrolyte 100 may be any organic material, such as an organic liquid, an ionic liquid, or any combinations thereof. If the organic liquid does not supply lithium ion, then electrolyte 100 also includes a lithium salt. In more specific embodiments, electrolyte 100 may also include an additive, such as an additive that reduces or prevents gas creating in cell 10, an additive the reduces or prevents manganese dissolution, or an additive the forms a passivation layer, particularly on the anode, or any combinations of such additives.
In some embodiments, the organic liquid may include:
In some more specific embodiments, the organic liquid includes a carbonic acid ester, an aliphatic carboxylic acid ester, a carboxylic acid ester, an ether, or any combination thereof.
In some embodiments, the additive that reduces or prevents gas creation may include vinylene carbonate (VC), poly(ethyl methacrylate) (PEMA), polyethyl phenylethylmalonamide (PEMAO), Li2Co3, and any combinations thereof.
In some embodiments, the additive that forms a passivation layer may include VC, as fluoroethylene carbonate (FEC), Poly(3,4-ethylenedioxythiophene) (PEDOT), poly(styrenesulfonate) (PSS), polyvinyl acrylate (PVA), polyethylene glycol (PEG), polyethylene oxide (PEO), poly(methyl methacrylate) (PMMA) and any combinations thereof.
In some embodiments, the additive reduces or prevents Mn dissolution may include VC, FEC, or any combinations thereof.
In some embodiments, the electrolyte 100 may include another additive, such as an anhydride, prop-1-ene-1,3-sultone (PES), or a combination thereof.
Electrolyte 100 may include any combinations of any or all additives.
In more specific embodiments, the total weight of additives may be about 5 wt % or less of the total electrolyte weight. In still more specific embodiments, the total weight of additive may be between about 1 wt % and about 5 wt %.
In some embodiments, the lithium salt includes LiPF6, LiFSi, LiTFSI, KFSI, KTFSI, LiBF4, CH3COOLi, CH3SO3Li, CF3SO3Li, CF3COOLi, Li2B12F12, LiBC4O8;
wherein Rf is F, CF3, CHF2, CH2F, C2HF4, C2H2F3, C2H3F2, C2F5, C3F7, C3H2F5, C3H4F3, C4F9, C4H2F7, C4H4F5, C5F11, C3F5OCF3, C2F4OCF3, C2H2F2OCF3 or CF2OCF3; or any combinations thereof.
In more specific embodiments, the electrolyte 100 may include between about 0.5 M and about 2 M lithium salt.
In other embodiments, electrolyte 100 is a chemical composition or mixture of chemical compositions that do not contain lithium hexafluorophosphate as an electrolyte lithium salt. The presence of lithium hexafluorophosphate in the electrolyte composition of lithium batteries has been shown to promote the production of hydrofluoric acid and hydrogen fluoride gas, both of which can lead to increased degradation of the cell or battery. An advantage of the electrolyte compositions disclosed herein is that they avoid or lower the production hydrofluoric acid and hydrogen fluoride gas in the cell or battery, as compared to otherwise similar electrolytes containing lithium hexafluorophosphate. This increases battery safety and may increase cycle life.
In some embodiments, the ionic liquid may be any ionic liquid that is a liquid at 20° ° C. In more specific embodiments, the ionic liquid may include bis(fluorosulfonyl)imide (FSI), bis(trifluoromethane)sulfonamide (TFSI), imidazolium, a phosphonium phosphate, a phosphonium thiophosphate, or any combinations thereof.
In more specific embodiments, electrolyte 100 may also include a flame retardant.
In some embodiments, the flame retardant includes a perfluorocarbon, an alkane, an ether, a ketone, an amine substituted with one or more alkyl groups, or any combinations thereof. In more specific embodiments, the flame retardant may be at least 60% fluorinated (i.e. 60% of the individual flame retardant molecules are fluoridated).
In some embodiments, the flame retardant includes a ketone having the general formula R′(C═O)R″, wherein R′ is a perfluoroalkyl group and R″ is a perfluoroalkyl group or an alkyl group. More specifically, the ketone is a perfluoroketone, such as dodecafluoro-2-methylpentan-3-one.
In other embodiments, the flame retardant includes an ether having the general formula R′OR″, wherein R′ is a perfluoroalkyl group and R″ is a perfluoroalkyl group or an alkyl group. In more specific embodiments, the ether is a segregated hydrofluoroether, such as methoxy-heptafluoropropane, methoxy-nonafluorobutane, ethoxy-nonafluorobutane, perfluorohexylmethylether, or 2-trifluoromethyl-3-ethoxydodecofluorohexane.
In some embodiments, the flame retardant does not contain ethers or, more specifically, fully or partially halogenated ethers.
In some embodiments, the flame retardant includes an amine substituted with one or more perfluoroalkyl groups, such as perfluorotripentylamine, perfluorotributylamine, perfluorotripropylamine, or perfluoro-n-dibutylmethylamine.
In some embodiments, flame retardant can include a perfluoroalkane such as perfluoropentane, perfluorohexane, perfluoroheptane, perfluoroctane, or perfluoro-1,3-dimethylcyclohexane.
In some embodiments, the flame retardant includes a phosphazene, such as a cyclic phosphazene, more particularly cyclotriphosphazene. In more specific embodiments, the cyclic phosphazene is fully or partially halogenated. In even more specific embodiments, the cyclic phosphazene is fully or partially fluorinated. In still other embodiments, additionally or alternately, the cyclic phosphazene has one or more substituents selected from linear or cyclic alkyl groups, alkoxy groups, cycloalkoxy groups, and aryloxy groups. In more specific embodiments, the substituents are unhaloghenated, fully halogenated or partially halogenated. In other more specific embodiments, the cyclic phosphazene is fully substituted with halogens and substituents such as linear or cyclic alkyl groups, alkoxy groups, cycloalkoxy groups, and aryloxy groups.
The present disclosure relates to electrodes arranged in stacks, such as stacks in which anode/separator/cathode/anode . . . alternate. In some embodiments, the electrode stacks having a slotted structure created by an accordion-shaped separator, which may be referred to as “slot electrodes” or “slot electrode stacks.” When the separator is folded into an accordion shape, it creates slots on alternating sides of the separator into with cathodes and anodes fit so that there is separator on both sides of each cathode or each anode. A plurality of stopping points, each located at an end of a slot, are also formed by the folds of the separator. These stopping points can help make assembly of the electrode stack easier or prevent electrodes from shifting position too far during use.
In some embodiments, an electrode stack may include alternating layers of cathode/separator/anode. Such a stack might exhibit edge effects, which create areas where electrochemical reactions cannot take place, decreasing the energy density of the cell or battery containing the electrode stack and also possibly resulting in dendrite formation. To avoid this, the ends of the stack may be cut off, for example, with a laser, to achieve more precise boundaries. In some embodiments, scarring resulting from such cutting is performed may be repaired placing metal on the ends of electrode the electrode stack at boundaries after they are cut. In some embodiments, aluminum metal may be placed at one cut edge and copper may be placed at the other cut edge, corresponding to positive and negative ends of the stack.
Batteries of the present disclosure include any high capacity anode or electrochemical cell disclosed herein. Batteries of the present disclosure may exhibit any of the electrochemical properties attributed to high capacity anodes, when located in an electrochemical cell, or electrochemical cells disclosed herein.
In some embodiments, the battery may be a simple electrochemical cell in a casing. In other embodiments, it may include a more complex electrochemical cell or plurality of cells. For example, in some embodiments, the electrodes may be separated by separators, then rolled within a casing as illustrated in
In some embodiments, the casing of a battery may be a polymeric film, a metallic foil, a metal can, or any combination thereof. In some embodiments, the casing may include a vent.
In some embodiments, the battery may be thus formed can be a coin or button cell battery, a cylindrical battery, or a prismatic cell battery or pouch cell battery.
In some embodiments, a battery as described herein includes active materials that provide a high degree of safety. Commercial lithium ion batteries have suffered from safety concerns due to occasions of batteries catching fire. In contrast with commercial batteries having relatively high energy capacity, the batteries described herein are based on active materials that do not share the corresponding instabilities of the commercial batteries and thus exhibit thermal run away to a significant lower extent or not at all. In some embodiments, if the batteries described herein are heated, they do not spontaneously react to catch fire. Relatively high energy commercial lithium ion batteries exhibit thermal runaway in which the heated cells undergo reaction and catch fire. Thus, the batteries described herein may provide improved energy capacity as well as providing increased safety during use.
Rechargeable batteries have a range of uses, such as mobile communication devices, such as phones, mobile entertainment devices, portable computers, combinations of these devices that are finding wide use, as well as transportation devices, such as automobiles and forklifts. Batteries as described herein may, therefore, be used in a variety of commercial forms.
In some embodiments, the casing 250 has a length L and an average diameter D. In some embodiments, the length L may be between about 2 cm and about 10 cm, about 3 cm and about 10 cm, about 4 cm and about 10 cm, about 4.4 cm and about 10 cm, about 4.45 cm and about 10 cm, about 5 cm and about 10 cm, about 5.05 cm and about 10 cm, about 6.5 cm and about 10 cm, about 2 cm and about 6.5 cm, about 4 cm and about 5.5 cm, or about 4.4 cm and about 5.05 cm, and the diameter D may be between about 1 cm and about 3.5 cm, about 1.05 cm and about 3.5 cm, about 1.45 cm and about 3.5 cm, about 1.5 cm and about 3.5 cm, about 1 cm and about 3 cm, or about 1 cm and about 2 cm, in any combinations of these ranges of lengths and diameters.
In other embodiments, the casing 250 has a length L and an average diameter D. In some embodiments, the length L may be between about 1 cm and about 10 cm, about 5 cm and about 10 cm, about 5 cm and about 8 cm, about 5 cm and about 7 cm, 5 cm and about 20 cm, about 5 cm and about 15 cm, about 5 cm and about 10 cm, 5 cm and about 1 m, about 10 cm and about 1 m, about 20 cm and about 1 m, or about 50 cm and about 1 m, and the diameter D may be between about 1 cm and about 10 cm, about 2 cm and about 6 cm, about 2 cm and about 5 cm, about 2 cm and about 10 cm, or about 5 cm and about 10 cm, in any combinations of these ranges of lengths and diameters.
Prismatic cell battery 300 further includes a casing 310, which is illustrated as a metal pouch.
Prismatic cell battery 300 further includes a casing 310, which is illustrated as a metal pouch. Prismatic cell battery 300 may have a length, L which may be between about 10 cm and about 1 m, between about 10 cm and about 500 cm, between about 10 cm and between about 100 cm, between about 25 cm and about 1 m, between about 25 cm and about 500 cm, between about 25 cm and about 100 cm, between about 50 cm and about 1 m, between about 50 cm and about 500 cm, between about 50 cm and about 100 cm, between about 100 cm and 1 m, or between about 100 cm and about 500 cm, a width, W, which may be between about 2 cm and about 20 cm, about 2 cm and about 10 cm, about 2 cm and about 5 cm, about 5 cm and about 20 cm, or about 5 cm and about 10 cm, and a height, H, between about 2 cm and about 50 cm, about 2 cm and about 20 cm, about 2 cm and about 10 cm, about 5 cm and about 50 cm, about 5 cm and about 20 cm, about 5 cm and about 10 cm, about 10 cm and about 50 cm, or about 10 cm and about 20 cm, in any combinations of these ranges of lengths, width, and heights.
The battery 400 may also include safety equipment 450, control equipment 460, or both. Safety equipment 450 and control equipment 460 may located inside housing 410, or all or part of safety equipment 450 or control equipment 460 may be located outside housing 410. In some embodiments safety equipment 450 may include equipment that minimizes damage should one of batteries 300 fail or potentially or actually cause damage. For example, safety equipment 450 may include a fan or a fire-suppression material and delivery system. In some embodiments control equipment 460 may include a processor and an associated memory, in which the processor is able to execute a program stored in the associated memory to control one or more functions of the battery 400. The processor may also receive information regarding battery 400, vehicle 470, or batteries 300 and use such information to control one or more functions of battery 400.
Batteries of the present disclosure may also be suitable for use with small electronics.
As illustrated in
As illustrated in
The various embodiments described above can be combined to provide further embodiments. Aspects of the embodiments can be modified in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.
The present application claims priority to U.S. Provisional Patent Application No. 63/277,083, filed Nov. 8, 2021, titled “BIPOLAR LITHIUM ION CATHODES AND CELLS AND BATTERIES CONTAINING LITHIUM ION CATHODES”, U.S. Provisional Patent Application No. 63/400,355, filed Aug. 23, 2022, titled “BIPOLAR LITHIUM ION CATHODES AND CELLS AND BATTERIES CONTAINING LITHIUM ION CATHODES”, U.S. Provisional Patent Application No. 63/277,084, filed Nov. 8, 2021, titled “LITHIUM ION CATHODES AND CELLS SUITABLE FOR LARGE-FORMAT BATTERIES AND LARGE-FORMAT BATTERIES CONTAINING LITHIUM ION CATHODES”, U.S. Provisional Patent Application No. 63/410,538, filed Sep. 27, 2022, titled “LITHIUM ION CATHODES AND CELLS SUITABLE FOR LARGE-FORMAT BATTERIES AND LARGE-FORMAT BATTERIES CONTAINING LITHIUM ION CATHODES”, U.S. Provisional Patent Application No. 63/310,979, filed Feb. 16, 2022, titled “HIGH CAPACITY LITHIUM ION ANODES AND CELLS AND BATTERIES CONTAINING LITHIUM ION ANODES”, and U.S. Provisional Patent Application No. 63/340,353, filed May 10, 2022, titled “SLOT ELECTRODE STACK AND ELECTROCHEMICAL CELLS AND BATTERIES CONTAINING A SLOT ELECTRODE STACK”, each of which is incorporated by reference herein in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2022/049324 | 11/8/2022 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63277083 | Nov 2021 | US | |
| 63277084 | Nov 2021 | US | |
| 63310979 | Feb 2022 | US | |
| 63340353 | May 2022 | US | |
| 63400355 | Aug 2022 | US | |
| 63410538 | Sep 2022 | US |
