Polymer binders including indicia for electrochemical cells

Abstract

The present disclosure provides an electrode material comprising an active material; a non-fluorinated polymer binder comprising a detectable label; and a conductive filler.

Description

Technical Field

[0001] This subject matter discloses battery cell technology, and more particularly polymer binders for electrodes used in electrochemical cells. Background Technology

[0002] High-voltage electrical systems are increasingly used to power onboard functions in both mobile and stationary systems. For example, in motor vehicles, the need for increased fuel economy and reduced emissions has led to the development of advanced electric vehicles (EVs). EVs rely on rechargeable energy storage systems (RESS), which typically include one or more high-voltage battery packs, along with an electric drivetrain to deliver electricity from the battery to the wheels. Depending on the power requirements of a given application, the battery pack can include any number of interconnected battery modules. Each battery module comprises an assembly of electrically coupled electrochemical cell units. The battery pack is configured to provide a direct current (DC) output voltage at a level suitable for powering coupled electrical and / or mechanical loads, such as an electric motor.

[0003] Electrodes in a battery are among the key components responsible for the electrochemical reactions that occur during charging and discharging. Modern automotive high-voltage battery packs benefit from high-energy-density electrodes to improve overall performance and range. However, there remains a persistent need for fluoropolymer binder materials, as well as the ability to quantitatively determine the distribution and eventual migration of polymer binders within electrode materials during battery assembly and subsequent operation. Summary of the Invention

[0004] One aspect provides an electrode material. The electrode material includes an active material; a non-fluorinated polymer binder containing a detectable label; and a conductive filler.

[0005] In another embodiment of the electrode material, a detectable marker of the non-fluorinated polymer binder is incorporated into the main chain of the polymer binder or serves as an end group of the main chain of the polymer binder.

[0006] In another embodiment of the electrode material, the backbone of the non-fluorinated polymer binder is a carboxymethyl cellulose (CMC) backbone, a polyacrylic acid (PAA) backbone, a styrene-butadiene rubber (SBR) backbone, or a styrene-butadiene rubber-carboxymethyl cellulose (SBR-CMC) backbone.

[0007] In another embodiment of the electrode material, a non-fluorinated polymer adhesive is prepared by reacting the functional groups of the main chain of the polymer adhesive with a detectable reagent to form a detectable tag bound to the main chain of the polymer adhesive.

[0008] In another embodiment of the electrode material, the detectable label includes fluorescein or a derivative thereof, rhodamine or a derivative thereof, acridine or a derivative thereof, coumarin or a derivative thereof, eosin or a derivative thereof, erythrosine or a derivative thereof, pyrene or a derivative thereof, or combinations thereof.

[0009] In another embodiment of the electrode material, the non-fluorinated polymer binder further comprises linking groups that connect the main chain to the detectable marker.

[0010] In another embodiment of the electrode material, the electrode material does not include a fluorinated binder.

[0011] On the other hand, an electrochemical cell is provided, comprising a positive electrode, a negative electrode, and an electrolyte. At least one of the positive or negative electrodes comprises an electrode material as described herein.

[0012] In another embodiment of the electrochemical cell, the marker can be detected as either attached to the main chain of the polymer binder or as an end group of the main chain of the polymer binder.

[0013] In another embodiment of the electrochemical cell, the main chain is a carboxymethyl cellulose (CMC) main chain, a poly(acrylic acid) (PAA) main chain, a styrene-butadiene rubber (SBR) main chain, or a styrene-butadiene rubber-carboxymethyl cellulose (SBR-CMC) main chain.

[0014] In another embodiment of the electrochemical cell, the polymer binder is prepared by reacting the functional groups of the polymer binder’s main chain with a detectable reagent to form a detectable tag bound to the main chain of the polymer binder.

[0015] In another embodiment of the electrochemical cell, the detectable label includes fluorescein or a derivative thereof, rhodamine or a derivative thereof, acridine or a derivative thereof, coumarin or a derivative thereof, eosin or a derivative thereof, erythrosine or a derivative thereof, pyrene or a derivative thereof, or combinations thereof.

[0016] In another embodiment of the electrochemical cell, the non-fluorinated polymer binder also includes linking groups that connect the main chain to a detectable marker.

[0017] In another embodiment of the electrochemical cell, the electrode material does not include fluorinated binders.

[0018] Another approach provides a method for measuring the distribution of a binder in an electrode material. The method includes providing an electrode material as described herein, exposing the electrode material to activation radiation sufficient to provide a quantitative signal from a detectable marker, and determining the distribution of a non-fluorinated polymer binder based on the quantitative signal from the detectable marker.

[0019] In another embodiment of the method, the method further includes charging and discharging the electrochemical cell containing the electrode material prior to the step of providing the electrode material.

[0020] In another embodiment of the method, the marker can be detected as being bound to the main chain of the polymer adhesive or as an end group of the main chain of the polymer adhesive.

[0021] In another embodiment of the method, the main chain is a carboxymethyl cellulose (CMC) main chain, a poly(acrylic acid) (PAA) main chain, a styrene-butadiene rubber (SBR) main chain, or a styrene-butadiene rubber-carboxymethyl cellulose (SBR-CMC) main chain.

[0022] In another embodiment of the method, the polymer adhesive is prepared by reacting the functional groups of the polymer adhesive backbone with a detectable reagent to form a detectable tag that is bound to the polymer adhesive backbone.

[0023] In another embodiment of the method, the electrode material does not include fluorinated binders.

[0024] The above-described features and advantages, as well as other features and advantages, of this disclosure will become apparent when taken in conjunction with the accompanying drawings and the following detailed description. Attached Figure Description

[0025] Other features, advantages, and details appear by way of example only in the following detailed description, which is described in detail with reference to the accompanying drawings, wherein:

[0026] Figure 1 It is a vehicle configured according to one or more embodiments;

[0027] Figure 2 An exemplary electrochemical cell (battery) including the disclosed electrode materials is illustrated schematically according to this disclosure.

[0028] Figure 3A This is a visual image of an example of an electrode material using scalar bars of 100 micrometers (μm);

[0029] Figure 3B These are visual images of an example of electrode material using scalar bars of 100 μm; and

[0030] Figure 3C This is a visual image of an example of electrode material using scalar bars of 100 μm. Detailed Implementation

[0031] The following description is exemplary in nature only and is not intended to limit this disclosure, its application, or use. It should be understood that throughout the drawings, corresponding reference numerals denote the same or corresponding parts and features. As used herein, the terms "anode" and "negative electrode" are used interchangeably, and the terms "cathode" and "positive electrode" are used interchangeably.

[0032] This technology relates to improved electrochemical batteries (e.g., battery cells), particularly lithium-ion batteries, or more particularly lithium metal batteries, which can be used in vehicle applications. However, this technology can also be used in other electrochemical devices, such as sodium-ion batteries, making the discussion of lithium-ion batteries herein non-limiting.

[0033] According to an exemplary embodiment, the vehicle is in Figure 1 The vehicle 10 is generally indicated by 10. The vehicle 10 is shown in the form of an automobile having a body 12. The body 12 includes a passenger compartment 14, within which a steering wheel, front seats, and rear passenger seats (not separately indicated) are arranged. Several components are arranged within the body 12, including, for example, an electric motor 16 (shown by a projection below the front hood). The electric motor 16 is shown only for ease of illustration and discussion. It should be understood that the construction, location, size, arrangement, etc., of the electric motor 16 are not intended to be particularly limited, and all such constructions (including multi-motor constructions) are within the scope of this disclosure.

[0034] The electric motor 16 is powered via a battery pack 18 (shown in projection near the rear of the vehicle 10). The battery pack 18 is shown for illustration and discussion only. It should be understood that the configuration, location, size, arrangement, etc., of the battery pack 18 are not intended to be particularly limited, and all such configurations (including split configurations) are within the scope of this disclosure. Furthermore, although this disclosure is discussed primarily in the context of the battery pack 18 configured for the electric motor 16 in the vehicle 10, the aspects described herein can be similarly incorporated into any system (vehicle, building, or otherwise) having an energy storage system (e.g., one or more battery packs or modules), and all such configurations and applications are within the scope of this disclosure.

[0035] As previously described, in some embodiments, battery pack 18 includes an electrochemical cell or battery pack comprising a positive electrode, a negative electrode, and an electrolyte. An electrochemical cell is also provided, comprising a cathode, an anode, and an electrolyte located between the cathode and the anode. Figure 2 A battery pack according to one or more embodiments is shown (e.g., Figure 1 A simplified configuration of the electrochemical cell in the battery pack 18). For example... Figure 2As shown, the electrochemical cell 200 may include a cathode 202 (i.e., the positive electrode), an anode 204 (i.e., the negative electrode), and an electrolyte 206 located between the cathode 202 and the anode 204. Although only a single electrochemical cell 200 is shown for convenience, it should be understood that the battery pack may include any number of cells as needed to meet battery design constraints (e.g., capacity requirements). At least one of the positive electrode (cathode 202) or the negative electrode (anode 204) comprises the electrode material as provided herein.

[0036] One aspect provides an electrode material. The electrode material comprises an active material, a non-fluorinated polymer binder containing a detectable label, and a conductive filler. The electrode material can be a cathode material or an anode material. For example, one or both of the cathode and anode materials may include a non-fluorinated polymer binder containing a detectable label. In some embodiments, the electrode material may exclude a fluorinated binder. For example, one or both of the cathode and anode materials may include a non-fluorinated polymer binder containing a detectable label, and one or both of the cathode and anode materials may not include a fluorinated binder.

[0037] Non-fluorinated polymer adhesives include detectable labels. Detectable labels provide signal generators and are molecules or portions capable of providing a detectable signal using one or more detection techniques (e.g., spectroscopic, calorimetric, spectroscopy, or visual inspection). Suitable examples of detectable signals may include optical and electrical or radioactive signals. Examples of signal generators that can be used in the methods of the present invention include, for example, chromophores, fluorophores, Raman-active labels, radioactive labels, enzymes, enzyme substrates, or combinations thereof. For example, a detectable label may be a luminescent label, a fluorescent label, or a combination thereof (which may be collectively referred to as a fluorophore, as described herein).

[0038] Suitable radioactive isotopes may include H-3, C-11, C-14, F-18, P-32, S-35, I-123, I-124, I-125, I-131, Cr-51, Cl-36, Co-57, Fe-59, Se-75, and Eu-152. Halogen isotopes (e.g., chlorine, fluorine, bromine, and iodine) and metals including technetium, yttrium, rhenium, and indium are also useful labels. Typical examples of metal ions that can be used as signal generators include Tc-99m, I-123, In-111, I-131, Ru-97, Cu-67, Ga-67, I-125, Ga-68, As-72, Zr-89, Gd-153, and Ti-201. Radioactive isotopes used for in vivo diagnostic imaging via positron emission tomography (“PET”) include C-11, F-18, Ga-68, and I-124. Paramagnetic labeling can be metal ions present as metal complexes or metal oxide particles. Suitable paramagnetic isotopes may include Gd-157, Mn-55, Dy-162, Cr-52, and Fe-56.

[0039] As used herein, the terms "paramagnetic metal ion," "paramagnetic ion," or "metal ion" refer to a metal ion that is magnetized to a degree proportional to the magnetic field, either parallel or antiparallel to it. Typically, these are metal ions possessing unpaired electrons. Examples of suitable paramagnetic metal ions include, but are not limited to, gadolinium III, iron III, manganese II, yttrium III, dysprosium III, and chromium III.

[0040] In some implementations, the detectable marker may be a fluorophore. As used herein, the term "fluorophore" refers to a chemical compound or portion that emits light (at different wavelengths) when excited by exposure to light of a specific wavelength. Fluorophores can be described by their emission profiles or "color." Green fluorophores (such as Cy3, FITC, and Oregon Green) are characterized by their emission wavelengths typically in the range of 515–540 nm. Red fluorophores (such as Texas Red, Cy5, and tetramethylrhodamine) are characterized by their emission wavelengths typically in the range of 590–690 nm.Examples of fluorophores include, but are not limited to, 4-acetamido-4'-isothiocyanate stilbene-2,2'-disulfonic acid, acridine, acridine and acridine isothiocyanate derivatives, 5-(2'-aminoethyl)aminonaphthalene-1-sulfonic acid (EDANS), 4-amino-N-[3-vinylsulfonyl)phenyl]naphthalenedicarboximide-3,5-disulfonate (fluorescein yellow VS), N-(4-anilino-1-naphthyl)maleimide, o-aminobenzamide, brilliant yellow, coumarin, coumarin derivatives, 7-amino-4-methylcoumarin (AMC, coumarin 120), 7-amino-trifluoromethylcoumarin (coumarin 151), cyanogenic glycosides; 4',6-diamidinyl-2-phenylindole (DAPI), 5 ',5'-Dibromopyrogallol-sulfonylphthalein (bromopyrogallol red), 7-diethylamino-3-(4'-isothiocyanate-phenyl)-4-methylcoumarin, 4,4'-diisothiocyanate-dihydro-stilbene-2,2'-disulfonic acid, 4,4'-diisothiocyanate-stilbene-2,2'-disulfonic acid, 5-[dimethylamino]naphthalene-1-sulfonyl chloride (DNS, dansyl chloride), eosin, eosin derivatives such as eosin isothiocyanate, erythrosin, erythrosin derivatives such as erythrosin B and erythrosin isothiocyanate; ethidium; fluorescein and its derivatives, such as 5-carboxyfluorescein (FAM), 5-(4,6-dichlorotriazine-2-yl)aminofluorescein (DTAF), 2'7'-dimethoxy- 4'5'-Dichloro-6-carboxyfluorescein (JOE), fluorescein, fluorescein isothiocyanate (FITC), QFITC ​​(XRITC); fluorescent amine derivatives (fluoresce upon reaction with amines); IR144; IR1446; malachite green isothiocyanate; 4-methylumbelliferone; o-cresolphthalein; nitrotyrosine; parasitine; phenol red, β-phycoerythrin; phthalaldehyde derivatives (fluoresce upon reaction with amines); pyrene and its derivatives, such as pyrene, pyrene butyrate, and succinimide-1-pyrene butyrate; Reactive Red 4 (Cibacron® Brilliant Red 3B-A), rhodamine and its derivatives such as 6-carboxy-X-rhodamine (ROX), 6-carboxyrhodamine (R6G), lissamine rhodamine B sulfonyl chloride. Rhodamine (Rhodamine), Rhodamine B, Rhodamine 123, Rhodamine X isothiocyanate, sulforhodamine B, sulforhodamine 101, and sulforhodamine 101 sulfonyl chloride derivatives (Texas Red); N,N,N',N'-tetramethyl-6-carboxyrhodamine (TAMRA); tetramethylrhodamine, tetramethylrhodamine isothiocyanate (TRITC); riboflavin; biotin; rosemary acid and lanthanide chelate derivatives, quantum dots, anthocyanins, and squaricine. In some embodiments, the detectable label may include fluorescein or a derivative thereof, rhodamine or a derivative thereof, acridine or a derivative thereof, coumarin or a derivative thereof, eosin or a derivative thereof, erythrosine or a derivative thereof, pyrene or a derivative thereof, or combinations thereof.

[0041] In some embodiments, the detectable marker may be bound to the main chain of the polymeric adhesive or serve as an end group of the polymeric adhesive main chain. Preferably, the detectable marker is bound to the main chain of the polymeric adhesive. The detectable marker may be bound to the main chain of the polymeric adhesive via a direct covalent bond or via one or more divalent linking groups. As used herein, unless otherwise defined, a "divalent linking group" refers to -O-, -S-, -C(O)-, -C(O)O-, -N(R')-, -C(O)N(R')-, -S(O)-, -S(O)2-, substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 3-30 Heterocyclic alkyl, substituted or unsubstituted C 6-30 aryl, substituted or unsubstituted C 3-30 One or more divalent groups of heteroaryl or combinations thereof, wherein each R' is independently hydrogen, substituted or unsubstituted C. 1-20 Alkyl, substituted or unsubstituted C 1-20 Heteroalkyl, substituted or unsubstituted C 6-30 Aryl or substituted or unsubstituted C3-30 heteroaryl groups. Typically, the divalent linking group includes -O-, -S-, -C(O)-, -C(O)O-, -N(R')-, -C(O)N(R')-, -S(O)-, -S(O)2-, substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 3-30 Heterocyclic alkyl, substituted or unsubstituted C 6-30 aryl, substituted or unsubstituted C 3-30 One or more of the heteroaryl group or combinations thereof, wherein R' is hydrogen, substituted or unsubstituted C. 1-20 Alkyl, substituted or unsubstituted C 1-20 Heteroalkyl, substituted or unsubstituted C 6-30 aryl or substituted or unsubstituted C 3-30 Heteroaryl groups. More typically, the divalent linking groups include -O-, -C(O)-, -C(O)O-, -N(R')-, -C(O)N(R')-, substituted or unsubstituted C- groups. 1-10 Alkylene, substituted or unsubstituted C 3-10 Cycloalkylene, substituted or unsubstituted C 3-10 Heterocyclic alkyl, substituted or unsubstituted C 6-10 aryl, substituted or unsubstituted C 3-10 At least one of heteroaryl groups or combinations thereof, wherein R is hydrogen, substituted or unsubstituted C. 1-10 Alkyl, substituted or unsubstituted C 1-10Heteroalkyl, substituted or unsubstituted C 6-10 aryl or substituted or unsubstituted C 3-10 Mixed aromatic compounds.

[0042] "Substituted" means that at least one hydrogen atom in a chemical structure or group is replaced by another terminal substituent, usually monovalent, provided that the valence does not exceed the normal valence of the specified atom. Exemplary substituents that may be present at the "substituted" position include, but are not limited to, nitro (-NO2), cyano (-CN), hydroxyl (-OH), oxo (O), amino (-NH2), mono- or di-(C) 1-6 )alkylamino, C 2-6 Alkyl (e.g., acyl), formyl (-C(O)H), carboxylic acid or its alkali metal salt or ammonium salt; C 2-6 Alkyl esters (-C(O)O-alkyl or -OC(O)-alkyl), C 7-13 Aryl esters (-C(O)O-aryl or -OC(O)-aryl); amide groups (-C(O)NR2, where each R is hydrogen or C). 1-6 alkyl), formamido (-CH2C(O)NR2, where each R is hydrogen or C 1-6 Alkyl groups, halogens, thiols (-SH), C 1-6 Alkylthio (-S-alkyl), thiocyano (-SCN), C 1-6 Alkyl, C 2-6 alkenyl, C 2-6 alkynyl group, C 1-6 Haloalkyl, C 1-9 Alkoxy, C 1-6 Halogenated alkoxy groups, C 3-12 cycloalkyl, C 5-18 Cycloalkenyl, C 2-18 Heterocyclic alkenyl groups, C groups having at least one aromatic ring 6-12 Aryl (e.g., phenyl, biphenyl, naphthyl, etc., where each ring is substituted or unsubstituted aromatic), C 7-19 arylalkyl, arylalkoxy, C 7-12 alkylaryl, C 3-12 Heterocyclic alkyl, C 3-12 heteroaryl, C 1-6 alkylsulfonyl (-S(O)2-alkyl) and / or C 6-12 Arylsulfonyl (-S(O)2-aryl).

[0043] The detectable markers may be included in the polymer structure in any suitable amount. For example, based on the total weight of the polymer adhesive, the polymer adhesive may include 0.01 wt% to 10 wt%, or 0.1 wt% to 5 wt%, or 0.1 wt% to 2 wt% of the detectable markers.

[0044] The polymeric adhesive comprises a backbone structure. For example, in some embodiments, the backbone may be a carboxymethyl cellulose (CMC) backbone, a poly(acrylic acid) (PAA) backbone, a styrene-butadiene rubber (SBR) backbone, or a styrene-butadiene rubber-carboxymethyl cellulose (SBR-CMC) backbone, but embodiments are not limited thereto, and any suitable polymeric adhesive may be used. The polymeric backbone structure may be further modified to include, or may inherently include, functional groups to facilitate the binding of detectable markers. Any suitable functional groups may be used and / or included. Exemplary functional groups include, but are not limited to, hydroxyl, thiols, isocyanates, isothiocyanates, esters, carbonyl groups, acyl halides, epoxy groups, amides, olefins, or combinations thereof.

[0045] Non-fluorinated polymer adhesives can be prepared using any suitable method in the art, including those exemplified in the working examples. For example, non-fluorinated polymer adhesives can be prepared by reacting the functional groups of the polymer adhesive backbone with a detectable reagent to form a detectable tag bound to the polymer adhesive backbone. For example, non-fluorinated polymer adhesives can be prepared by reacting the functional groups of the polymer adhesive backbone with a fluorophore to form a detectable tag bound to the polymer adhesive backbone, said detectable tag being bound to the backbone via one or more divalent linking groups as described herein.

[0046] In some embodiments, non-fluorinated polymer adhesives can be prepared by reacting polysaccharide-containing polymers (such as carboxymethyl cellulose (CMC) backbones, styrene-butadiene rubber carboxymethyl cellulose (SBR-CMC) backbones, etc.) with fluorophores using isothiocyanate coupling, carbonyl coupling chemistry, or isocyanate coupling. In some embodiments, non-fluorinated polymer adhesives can be prepared by reacting carbonyl-containing polymers (such as poly(acrylic acid) (PAA) backbones, etc.) with amine-containing fluorophores. In some embodiments, non-fluorinated polymer adhesives can be prepared by reacting olefin-containing polymers (such as styrene-butadiene rubber (SBR) backbones, styrene-butadiene rubber carboxymethyl cellulose (SBR-CMC) backbones, etc.) with fluorophores using free radical grafting, thiol-olefin coupling, or Diels-Alder reactions.

[0047] An electrochemical cell is also provided, comprising a cathode, an anode, and an electrolyte located between the cathode and the anode. As described above, Figure 2 A battery pack according to one or more embodiments is shown (e.g., Figure 1 A simplified configuration of the electrochemical cell unit of the battery pack 18).

[0048] In some embodiments, the active material (also referred to as the electroactive material) of the cathode 202 can include a lithium-containing active material that can sufficiently undergo lithium insertion and extraction, alloying and dealloying, and / or plating and stripping while serving as the positive terminal of the electrochemical cell 200. The electroactive material of the cathode 202 can include one or more transition metals such as manganese (Mn), nickel (Ni), cobalt (Co), chromium (Cr), iron (Fe), vanadium (V), or a combination thereof. Exemplary lithium-containing active materials include spinel lithium manganese oxide (LiMn2O4), lithium cobalt oxide (LiCoO2), nickel manganese oxide spinel (Li(Ni 0.5 Mn 1.5 )O2), layered nickel manganese cobalt oxide (having the general formula xLi2MnO 3（1-x） LiMO2, where M is composed of any ratio of Ni, Mn, and / or Co). Specific examples of layered nickel manganese oxide spinel are xLi2MnO 3（1-x） Li(Ni 1 / 3 Mn 1 / 3 CO 1 / 3 )O2. Other exemplary lithium-containing cathode active materials include Li(Ni 1 / 3 Mn 1 / 3 Co 1 / 3 )O2), LiNiO2, Li x+y Mn 2-y O4 (LMO, 0 < x < 1 and 0 < y < 0.1), lithium iron polyanion oxides such as lithium iron phosphate (LiFePO4) or lithium iron fluorophosphate (Li2FePO4F, LFP), or a combination thereof. Other lithium-containing cathode active materials can also be used, such as LiNi x M 1-x O2 (M is composed of any ratio of Al, Co, and / or Mg), LiNi 1-x Co 1- y M x+y O2 or LiMn 1.5-x Ni 0.5-y M x+y O4 (M is composed of any ratio of Al, Ti, Cr, and / or Mg), stable lithium manganese oxide spinel (Li x Mn2-yMyO4, where M is composed of any ratio of Al, Ti, Cr, and / or Mg), lithium nickel cobalt aluminum oxide (e.g., LiNi 0.8 Co 0.15 Al 0.05 O2 or NCA), aluminum-stabilized lithium manganese oxide spinel (Li x Mn 2-x Al y O4), NCMA (LiNi 1-x-y-zCo x Mn y Al z O2 (where 0.02≤x≤0.20, 0.01≤y≤0.12 and 0.01≤z≤0.08), lithium vanadium oxide (LiV2O5), Li2MSiO4 (M is composed of Co, Fe and / or Mn in any ratio), high-efficiency nickel-manganese-cobalt materials (HE-NMC, NMC or LiNiMnCoO2), olivine LiMn x Fe （1-x） PO4 (LMFP) and combinations thereof. "Any ratio" means that any element can be present in any amount. In another example, anionic substitution can be performed in the lattice of any instance of a lithium transition metal active material to stabilize the crystal structure. For example, any O atom can be replaced by an F atom. In some embodiments, the cathode comprises NCM 111, NCM 532, NCM 622, NCM 712, NCM 811, NCMA, NCA, LNMO, or combinations thereof. In some embodiments, the cathode comprises NCMA.

[0049] In some embodiments, electrolyte 206 serves as a separator to provide a physical barrier between cathode 202 and anode 204. In some embodiments, electrolyte 206 includes a dendrite barrier layer, one or more interface layers, and / or one or more electrolyte layers (not shown separately). In some embodiments, in addition to providing a physical barrier between cathode 202 and anode 204, electrolyte 206 may also provide a path of minimum resistance for the internal channels of lithium ions (and associated anions) during lithium-ion cycling to facilitate the operation of electrochemical cell 200.

[0050] Electrolyte 206 provides a medium for the conduction of lithium ions between cathode 202 and anode 204 via electrochemical cell 200, and may be in solid, liquid, or gel form. In various aspects, electrolyte 206 may comprise a non-aqueous liquid electrolyte solution comprising a lithium salt dissolved in a non-aqueous aprotic organic solvent or a mixture of non-aqueous aprotic organic solvents. Non-limiting examples of lithium salts include lithium hexafluorophosphate (LiPF6), lithium perchlorate (LiClO4), lithium tetrachloroaluminate (LiAlCl4), lithium iodide (LiI), lithium bromide (LiBr), lithium thiocyanate (LiSCN), lithium tetrafluoroborate (LiBF4), lithium tetraphenylborate (LiB(C6H5)4), lithium bis(oxaloyl)borate (LiB(C2O4)2) (LiBOB), lithium difluorooxaloylborate (LiBF2(C2O4)), lithium hexafluoroarsenate (LiAsF6), lithium trifluoromethanesulfonate (LiCF3SO3), lithium bis(fluorosulfonyl)imide (LiN(CF3SO2)2), lithium bis(fluorosulfonyl)imide (Li(FSO2)2) (LiSFI), and lithium triethylene glycol dimethyl ether (triethylene glycol dimethyl ether). Lithium bis(trifluoromethanesulfonyl)imide (Li(FSO2) (TFSI), lithium bis(trifluoromethanesulfonyl)imide (Li(CF3SO2) (TFSI), lithium bis(trifluoromethanesulfonyl)imide (Li(F3) (TFSI)), lithium bis(trifluoromethanesulfonyl)imide (LiTFSA) and combinations thereof. Ethyl carbonate (DMC), diethyl carbonate (DEC), methyl ethyl carbonate (EMC)), aliphatic carboxylic acid esters (e.g. methyl formate, methyl acetate, methyl propionate), γ-lactones (e.g. γ-butyrolactone, γ-valerolactone), chain ethers (e.g. 1,2-dimethoxyethane, 1,2-diethoxyethane, ethoxymethoxyethane), cyclic ethers (e.g. tetrahydrofuran, 2-methyltetrahydrofuran), 1,3-dioxolane), etc.

[0051] In some embodiments, the electrolyte may be a solid electrolyte. The solid electrolyte may include one or more solid electrolyte particles, which may include one or more polymer-containing particles, oxide-containing particles, sulfide-containing particles, halide-containing particles, borate-containing particles, nitride-containing particles, hydride-containing particles, or combinations thereof. Exemplary solid electrolytes include, but are not limited to, LiTi2(PO4)3, LiGe2(PO4)3, and Li7La3Zr2O. 12 Li 3x La 2 / 3-x TiO3, Li3PO4, Li3N, Li4GeS4, Li 10 GeP2S 12 , Li2S-P2S5, Li6PS5Cl, Li6PS5Br, Li6PS5I, Li3OCl, Li 2.99Ba 0.005 ClO or combinations thereof.

[0052] In some embodiments, the anode 204 includes an electroactive material, such as a lithium host material capable of serving as the negative terminal of the electrochemical cell 200. In various aspects, the electroactive material includes lithium and may be lithium metal. In some embodiments, the anode 204 may include an electroactive lithium host material, such as graphite. In some embodiments, the anode 204 may include a conductive material, and one or more polymer binder materials to structurally hold the graphite material together. For example, the negative electrode may include a polymer binder as disclosed herein.

[0053] The negative electrode may comprise more than or equal to about 50% to less than or equal to about 100% of an electroactive material (e.g., graphite or a blend of graphite and lithium-ionized silicon oxide), optionally less than or equal to about 30% of a conductive material, and the balance being a binder. For example, in some embodiments, the anode 204 may comprise an active material comprising graphite particles mixed with a binder material. When the binder material is not a non-fluorinated polymer binder containing a detectable label, as a non-limiting example, it may be polyvinylidene fluoride (PVdF), ethylene propylene diene monomer (EPDM) rubber and / or carboxymethoxycellulose (CMC), styrene-butadiene rubber (SBR), compounds and / or mixtures of CMC and SBR, nitrile rubber (NBR), lithium polyacrylate (LiPAA), sodium polyacrylate (NaPAA), sodium alginate, lithium alginate, and combinations thereof. Suitable additional conductive materials may include carbon-containing materials and / or conductive polymers. Carbon-containing materials can include, for example, conductive carbon black, conductive acetylene black, acetylene black, carbon black, graphite, graphene, graphene oxide, carbon nanofibers, carbon nanotubes, etc. Examples of conductive polymers include polyaniline, polythiophene, polyacetylene, polypyrrole, etc. In some applications, mixtures of these conductive materials may be used.

[0054] In some embodiments, the cathode material or the material used to prepare the cathode may include a solvent, a binder, and / or a slurry stabilizer (not shown separately). The solvent may be selected from known materials depending on the choice of the cathode active material. For example, the solvent used for the NCMA active material may include N-methyl-2-pyrrolidone (NMP). Other solvents include cyclic carbonates (e.g., ethylene carbonate (EC), propylene carbonate (PC), butyl carbonate (BC), fluoroethylene carbonate (FEC)); acyclic (i.e., linear) carbonates (e.g., dimethyl carbonate (DMC), diethyl carbonate (DEC), methyl ethyl carbonate (EMC)); aliphatic carboxylic acid esters (e.g., methyl formate, methyl acetate, methyl propionate); γ-lactones (e.g., γ-butyrolactone, γ-valerolactone); chain ethers (e.g., 1,2-dimethoxyethane, 1,2-diethoxyethane, ethoxymethoxyethane); cyclic ethers (e.g., tetrahydrofuran, 2-methyltetrahydrofuran, 1,3-dioxolane); or combinations thereof.

[0055] The cathode active material can be mixed with an adhesive and / or a conductive filler. In some embodiments, the adhesive used for the cathode active material can be a non-fluorinated polymer adhesive of the present invention containing a detectable marker. In other embodiments, the adhesive used for the cathode active material can be another adhesive, such as polyvinylidene fluoride (PVdF), polyethylene oxide (PEO), ethylene propylene diene monomer (EPDM) rubber, carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), styrene-butadiene rubber-carboxymethyl cellulose (SBR-CMC), polyacrylic acid (PAA), cross-linked polyacrylic acid-polyethyleneimine, polyimide, polyvinyl alcohol (PVA), sodium alginate, combinations thereof, or other suitable adhesives. Examples of conductive fillers are high surface area carbons, such as acetylene black. The adhesive holds the electrode materials together, and the conductive filler ensures good electronic conduction between the positive electrode current collector and the active material particles of the cathode.

[0056] In some embodiments, the electrochemical cell may further include a separator (not shown). Exemplary separators include polymeric membranes, such as polypropylene membranes or coated polypropylene membranes. The separator may include a polyolefin-containing material having the general formula (CH2CHR)n, where R is an alkyl group. In some embodiments, the separator may include a single polyolefin or a combination of polyolefins. Examples of polyolefins include polyethylene (PE), polypropylene (PP), polyamide (PA), poly(tetrafluoroethylene) (PTFE), polyvinylidene fluoride (PVdF), poly(vinyl chloride) (PVC), and / or polyacetylene. Examples of other polymeric materials that may be included in or used to form the separator include cellulose, polyimide, copolymers of polyolefins and polyimide, poly(lithium 4-styrene sulfonate) coated polyethylene, polyetherimide (PEI), bisphenol-acetone phthalic anhydride (BPADA), p-phenylenediamine, poly(m-phenylene isophthalamide) (PMIA), and / or expanded polytetrafluoroethylene-hexafluoropropylene reinforced with polyvinylidene fluoride.

[0057] The current collectors for the cathode and / or anode can be any suitable conductive material. For example, current collectors may include copper, nickel, titanium, platinum, gold, silver, magnesium, aluminum, vanadium, their alloys, or combinations thereof. Current collectors may have a thickness from 10 nanometers (nm) to 1000 nm. For example, current collectors may have a thickness from 10 nm to 500 nm, or 50 nm to 400 nm, or 100 nm to 400 nm, but the embodiments are not limited thereto.

[0058] A method for measuring the distribution of a binder in an electrode material is also provided, comprising providing an electrode material as disclosed herein; exposing the electrode material to activation radiation sufficient to provide a quantitative signal from the detectable marker; and determining the distribution of a non-fluorinated polymer binder based on the quantitative signal from the detectable marker.

[0059] In some embodiments, the method may further include determining the distribution of the binder in the electrode material prior to using the electrode material during operation of the electrochemical cell. In other embodiments, the method may further include charging and discharging the electrochemical cell comprising the electrode material prior to the step of providing the electrode material. The electrochemical cell can be charged and discharged any number of cycles before the distribution of the non-fluorinated polymer binder can be determined as provided herein.

[0060] In terms of hardware architecture, the determination of the quantitative signal from the detectable marker and the distribution of the non-fluorinated polymer adhesive can be implemented in part using a computing device, which may include a processor, memory, and one or more input and / or output (I / O) device interfaces communicatively coupled via a local interface. The local interface may include, for example, but not limited to, one or more buses and / or other wired or wireless connections. The local interface may have additional elements omitted for simplicity, such as controllers, buffers (caches), drivers, repeaters, and receivers, to enable communication. Furthermore, the local interface may include address, control, and / or data connections to enable appropriate communication between the aforementioned components.

[0061] When a computing device is in operation, a processor can be configured to execute software stored in memory, to transfer data to and from memory, and typically to control the operation of the computing device. The software in memory is read, in whole or in part, by the processor, possibly buffered within the processor, and then executed. A processor can be a hardware device used to execute software, particularly software stored in memory. A processor can be a custom or commercially available processor, a central processing unit (CPU), an auxiliary processor among several processors associated with a computing device, a semiconductor-based microprocessor (in the form of a microchip or chipset), or any device typically used to execute software.

[0062] Memory may include any one or a combination of volatile memory elements (e.g., random access memory (RAM, such as DRAM, SRAM, SDRAM, VRAM, etc.)) and / or non-volatile memory elements (e.g., ROM, hard disk drive, CD-ROM, etc.). Furthermore, memory may contain electronic, magnetic, optical, and / or other types of storage media. Note that memory may also have a distributed architecture, where various components are geographically separated but accessible by a processor.

[0063] Software in memory can include one or more individual programs, each comprising an ordered list of executable instructions for implementing logical functions. System components embodied as software can also be interpreted as source programs, executable programs (object code), scripts, or any other entity containing a set of instructions to be executed. When constructed as source programs, programs are translated by compilers, assemblers, interpreters, etc., and may or may not be included in memory.

[0064] It should be noted that any functionality described herein can be embodied in any computer-readable medium for use or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, a processor-containing system, or other system that can fetch and execute instructions from and from an instruction execution system, apparatus, or device. In the context of this document, a “computer-readable medium” contains, stores, communicates, propagates, and / or transmits programs for use or in connection with an instruction execution system, apparatus, or device. A computer-readable medium can be, for example, but not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices. More specific examples (not an exhaustive list) of computer-readable media include portable computer disks (magnetic), random access memory (RAM) (electronic), read-only memory (ROM) (electronic), erasable programmable read-only memory (EPROM or flash memory) (electronic), and portable optical disc read-only memory (CDROM) (optical).

[0065] Example

[0066] Example 1

[0067]

[0068] In the diagram above, Base: base, Solvent: solvent.

[0069] In one example, CMC can be reacted directly with isothiocyanate-functionalized FITC in a solvent. The resulting polymer adhesive may include 0.1 wt% of FITC tags bound to the CMC polymer backbone.

[0070] Figure 3A , 3B The images shown in Figures 3 and 3C are exemplary fluorescence images that can be obtained for an electrode comprising a polymer binder with a label prepared in Example 1. These images can be used quantitatively to determine the distribution of the polymer binder within the electrode.

[0071] Example 2

[0072]

[0073] In the diagram above, Amide coupling and Base are the bases.

[0074] In a second example, PAA can be reacted directly with amino-functionalized FITC in a solvent. The resulting polymeric adhesive may include 0.1 wt% of FITC tags bound to the PAA polymer backbone.

[0075] Example 3

[0076]

[0077] In the above figure, Hours: hours; Development and application of a poly(acrylicacid)-grafted styrene-butadiene rubber as a binder system for silicon-graphite anodes in li-ion batteries: development and application of poly(acrylicacid)-grafted styrene-butadiene rubber as a binder system for silicon-graphite anodes in lithium-ion batteries.

[0078] In a third example, SBR can be reacted directly with olefin-functionalized FITC in a solvent. The resulting polymer adhesive may include 0.1 wt% of FITC tags bound to the SBR polymer backbone.

[0079] Throughout this specification, references to “one example,” “another example,” “example,” etc., mean that a particular element described in connection with that example (e.g., a feature, structure, and / or characteristic) is included in at least one example described herein and may or may not be present in other examples. Furthermore, it should be understood that, unless the context explicitly states otherwise, the elements described in any example may be combined in any suitable manner across various examples.

[0080] The terms “a” and “an” do not indicate a limitation of quantity, but rather that at least one of the referenced items is present. Unless the context clearly indicates otherwise, the term “or” means “and / or”. Throughout the specification, reference to “aspect” means that a particular element described in connection with that aspect (e.g., a feature, structure, step, or characteristic) is included in at least one aspect described herein and may or may not be present in other aspects. Furthermore, it should be understood that the described elements may be combined in any suitable manner in the aspects.

[0081] When an element, such as a layer, film, region, or substrate, is referred to as being “on” another element, it can be directly on the other element, or there may be intermediate elements present. Conversely, when an element is referred to as being “directly” on another element, there are no intermediate elements present.

[0082] Unless otherwise stated herein, all test standards are the most recent standards effective as of the filing date of this application, or, if priority is claimed, the most recent standards effective as of the filing date of the earliest priority application in which a test standard appears. Unless otherwise defined, the technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0083] While the foregoing disclosure has been described with reference to exemplary embodiments, those skilled in the art will understand that various changes can be made and elements can be substituted with equivalents without departing from its scope. Furthermore, many modifications can be made to adapt particular situations or materials to the teachings of this disclosure without departing from the basic scope of this disclosure. Therefore, this disclosure is intended to be limited to the specific embodiments disclosed, but will include all embodiments falling within its scope.

Claims

1. An electrode material, comprising: Active materials; Non-fluorinated polymer adhesives containing detectable markers; and Conductive filler.

2. The electrode material of claim 1, wherein the detectable marker is incorporated into the main chain of the polymer adhesive or serves as an end group of the main chain of the polymer adhesive; optionally, it further comprises a linking group connecting the main chain to the detectable marker.

3. The electrode material according to claim 1, wherein: The main chain is a carboxymethyl cellulose (CMC) main chain, a poly(acrylic acid) (PAA) main chain, a styrene-butadiene rubber (SBR) main chain, or a styrene-butadiene rubber-carboxymethyl cellulose (SBR-CMC) main chain; Detectable markers include fluorescein or its derivatives, rhodamine or its derivatives, acridine or its derivatives, coumarin or its derivatives, eosin or its derivatives, erythrosine or its derivatives, pyrene or its derivatives, or combinations thereof. Their combination.

4. The electrode material according to claim 1, wherein the non-fluorinated polymer binder is prepared by reacting the functional groups of the main chain of the polymer binder with a detectable reagent to form a detectable tag bound to the main chain of the polymer binder.

5. An electrochemical battery, comprising: Positive electrode; negative electrode; and Electrolytes, The positive electrode or at least one of the negative electrodes comprises the electrode material as described in claim 1.

6. The electrochemical cell of claim 5, wherein the detectable marker is incorporated into the main chain of the polymer binder or serves as an end group of the main chain of the polymer binder; optionally, it further comprises a linking group connecting the main chain to the detectable marker.

7. The electrochemical battery according to claim 5, wherein, The main chain is a carboxymethyl cellulose (CMC) main chain, a polyacrylic acid (PAA) main chain, a styrene-butadiene rubber (SBR) main chain, or a styrene-butadiene rubber-carboxymethyl cellulose (SBR-CMC) main chain; Detectable markers include fluorescein or its derivatives, rhodamine or its derivatives, acridine or its derivatives, coumarin or its derivatives, eosin or its derivatives, erythrosine or its derivatives, pyrene or its derivatives, or combinations thereof. Their combination.

8. The electrochemical cell of claim 5, wherein the polymer binder is prepared by reacting the functional groups of the main chain of the polymer binder with a detectable reagent to form the detectable label bound to the main chain of the polymer binder.

9. A method for measuring the distribution of binder in an electrode material, the method comprising: Provide the electrode material of claim 1; The electrode material is exposed to activation radiation sufficient to provide a quantitative signal from the detectable marker; and The distribution of the non-fluorinated polymer adhesive is determined based on a quantitative signal from the detectable marker.

10. The method of claim 9, further comprising charging and discharging the electrochemical cell containing the electrode material prior to the step of providing the electrode material.

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