FI20215234A1 - Composition for lithium-ion battery cathode - Google Patents

Composition for lithium-ion battery cathode Download PDF

Info

Publication number
FI20215234A1
FI20215234A1 FI20215234A FI20215234A FI20215234A1 FI 20215234 A1 FI20215234 A1 FI 20215234A1 FI 20215234 A FI20215234 A FI 20215234A FI 20215234 A FI20215234 A FI 20215234A FI 20215234 A1 FI20215234 A1 FI 20215234A1
Authority
FI
Finland
Prior art keywords
phosphonic acid
acid
lithium
organic phosphonic
water
Prior art date
Application number
FI20215234A
Other languages
Finnish (fi)
Swedish (sv)
Inventor
Salla Puupponen
Tapio Honkanen
Original Assignee
Kemira Oyj
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kemira Oyj filed Critical Kemira Oyj
Priority to FI20215234A priority Critical patent/FI20215234A1/en
Priority to PCT/FI2022/050132 priority patent/WO2022184980A1/en
Publication of FI20215234A1 publication Critical patent/FI20215234A1/en

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/621—Binders
    • H01M4/622—Binders being polymers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/04—Processes of manufacture in general
    • H01M4/0402—Methods of deposition of the material
    • H01M4/0404—Methods of deposition of the material by coating on electrode collectors
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/131—Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • H01M4/1391—Processes of manufacture of electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
    • H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/028—Positive electrodes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Abstract

The present invention relates to a binder formulation and a composition for lithiumion battery cathode. The present invention also relates to a method for producing the composition. The present invention further relates to an electrode comprising an active material layer formed from the composition a current collector.

Description

COMPOSITION FOR LITHIUM-ION BATTERY CATHODE
TECHNICAL FIELD The present disclosure generally relates to a lithium-ion battery cathode composition. The disclosure relates particularly, though not exclusively, to a lithium- ion battery cathode composition comprising cathode active material, conductive additive, water-soluble binder and phosphonic or a salt thereof. The disclosure additionally relates to an electrode for a lithium-ion battery comprising a current collector and active material layer formed from the composition on the collector.
BACKGROUND This section illustrates useful background information without admission of any technique described herein representative of the state of the art. Lithium ion battery (LiB) cathodes usually consist of active material (e.g. lithium nickel manganese cobalt oxides (NMC) or lithium ferro phosphate LiFePO4), electrical conducitivity enhancing additive (e.g. carbon nanotube, graphene, or carbon black) and binder, which binds the electrode components together and to the aluminum current collector. Currently, polyvinylidene fluoride (PVDF) is the well-established cathode binder in LiBs. PVDF is thermally stable and chemically inert over the used potential N range. However, halogenated PVDF requires environmentally harmful organic N- N methylpyrrolidone (NMP) solvent and is reactive towards lithiated graphite.
S
O © 25 Due to these disadvantages, other binder chemistries have been researched for
I = PVDF replacement. Polyacrylic acids (PAA) have been identified as potential = binders for LiB electrodes PAA can be in acidic form, or it can be partly or
N O completely neutralized e.g. with sodium, lithium or potassium.
QA O N
Organic phosphonate additives or fluorinated phoshphonates are generally used in LiB anodes (graphite) as flame retardant. Organic phosphonates may have additional functions apart from their main use as flame retard, such as enhancement of the thermal stability.
SUMMARY In a first aspect the present invention provides a lithium-ion battery cathode binder formulation comprising at least one water-soluble binder and at least one organic phosphonic acid or at least one phosphonate salt of the organic phosphonic acid or a mixture of at least one organic phosphonic acid and at least one phosphonate salt of the organic phosphonic acid.
In a second aspect the present invention provides a lithium-ion battery cathode composition comprising at least one cathode active material, at least one electrical conducitivity enhancing additive, at least one water-soluble binder, and at least one organic phosphonic acid or at least one phosphonate salt of the organic phosphonic acid or a mixture of the at least one organic phosphonic acid and the at least one phosphonate salt of the organic phosphonic acid.
In athird aspect the present invention provides an electrode for a lithium-ion battery comprising an aluminum current collector and at least one active material layer on at least one surface of the aluminum current collector, wherein the at least one active material layer is formed from the cathode composition according to the present N invention.
N 25 S In a fourth aspect the present invention provides a method for producing a lithium- S ion battery cathode composition, wherein the method comprises mixing water, at E least one electrical conducitivity enhancing additive, at least one water-soluble S binder and at least one organic phosphonic acid or at least one phosphonate salt of = 30 the organic phosphonic acid or a mixture of the at least one organic phosphonic acid and the at least one phosphonate salt of the organic phosphonic acid and optionally at least one thickening agent for producing a mixture, followed by adding at least one cathode active material to the mixture.
In a fifth aspect the present invention provides a method for producing an electrode for a lithium-ion battery cathode, wherein the method comprises mixing water, at least one electrical conducitivity enhancing additive, at least one water-soluble binder and at least one organic phosphonic acid or at least one phosphonate salt of the organic phosphonic acid or a mixture of the at least one organic phosphonic acid and the at least one phosphonate salt of the organic phosphonic acid and optionally at least one thickening agent, followed by adding at least one cathode active material to the mixture for producing a composition (slurry), followed by coating an aluminum current collector with the slurry and drying the coated aluminum current collector.
In a sixth aspect the present invention provides a lithium-ion battery comprising the electrode for a lithium-ion battery according to the present invention.
In a seventh aspect the present invention provide use of the lithium-ion battery cathode composition according to the present invention for an electrode for a lithium-ion battery.
It was surprisingly found that a cathode composition comprising at least one cathode active material, at least one electrical conducitivity enhancing additive, at least one water-soluble binder and at least one organic phosphonic acid or at least S 25 one phosphonate salt of the organic phosphonic acid or a mixture of the at least one se organic phosphonic acid and the at least one phosphonate salt of the organic © phosphonic acid results in more even and homogeneous lithium battery cathode I composition as compared to lithium battery cathode composition not comprising a < the phosphonic acid or the phosphonate salt of the organic phosphonic acid. & 30 N It was also surprisingly found that a cathode composition comprising at least one N cathode active material, at least one electrical conducitivity enhancing additive, at least one water-soluble binder and at least one organic phosphonic acid or at least one phosphonate salt of the organic phosphonic acid or a mixture of the at least one organic phosphonic acid and the at least one phosphonate salt of the organic phosphonic acid has improved discharge capacity and charge-discharge cycle stability as compared to lithium battery cathode composition not comprising the phosphonic acid or the phosphonate salt of the organic phosphonic acid. Additionally, it was found that by selecting pH of the water-soluble binder so that pH of the cathode composition is 7 or close to 7, corrosion of aluminum current collector and leaching/degradation of active material, such as Ni and Li, can be prevented. The appended claims define the scope of protection.
BRIEF DESCRIPTION OF THE FIGURES Figure 1a shows optical microscopy image of electrode formed from PAA binder slurry according to reference Example 3. Figure 1b shows optical microscopy image of electrode formed from: PAA + HEDP, PAA:HEDP weight fractions 80:20 according to the present invention Example 4.
Figure 2 shows results of rate capability measurements of LiBs composed of cathode slurries of Reference Examples 1 and 3 and Example 4 according to the — present invention.
S g 25 Figure 3 shows relative average specific discharge capacities of LiB half-cells of S slurries of Reference Examples 1 and 3 and Example 4 according to the present E invention. 5 DETAILED DESCRIPTION 3 In a first aspect the present invention provides a lithium-ion battery cathode binder formulation. The binder formulation comprises at least one water-soluble binder and at least one organic phosphonic acid or at least one phosphonate salt of the organic phosphonic acid or a mixture of at least one organic phosphonic acid and at least one phosphonate salt of the organic phosphonic acid. 5 In one embodiment solvent of the formulation is polar solvent. In one embodiment the formulation is aqueous (water) based formulation. In one embodiment solvent of the formulation is organic.
The formulation may comprise compounds having aromatic groups and/or halogenated compounds. In one embodiment the binder formulation comprises 1-50 wt.%, preferably 1-25 wt%, more preferably 1-10 wt.% of the organic phosphonic acid or the phosphonate salt of the organic acid or a mixture of at least one organic phosphonic acid and at least one phosphonate salt of the organic phosphonic acid. In one embodiment the organic phoshonic acid comprises Amino Trimethylene Phosphonic Acid (ATMP) CAS No. 6419-19-8, 1-Hydroxy Ethylidene-1,1- Diphosphonic Acid (HEDP) CAS No. 2809-21-4, Ethylene Diamine Tetra (Methylene Phosphonic Acid) (EDTMPA) CAS No. 1429-50-1, Diethylene Triamine Penta (Methylene Phosphonic Acid) (DTPMPA) CAS No. 15827-60-8, 2-Phosphonobutane -1,2,4-Tricarboxylic Acid (PBTC) CAS No. 37971-36-1, 2- S 25 Hydroxy Phosphonoacetic — Acid (HPAA) CAS No. 23783-26-8, se HexaMethyleneDiamineTetra (MethylenePhosphonic Acid) (HMDTMPA) CAS © No. 23605-74-5, Hydroxyethylamino-Di(Methylene Phosphonic Acid) (HEMPA) I CAS No. 5995-42-6, Triethylene-tetramine Hexmethanephonic Acid (TETHMP), < Polyamino Polyether Methylene Phosphonic Acid (PAPEMP), Bis(HexaMethylene & 30 — Triamine Penta (Methylene Phosphonic Acid) (BHMTPMP) CAS No. 34690-00-1, N ethyl phosphonic acid (EPA), (2-aminoethyl)phosphonic acid, 2-chloro- N ethylphosphonic acid, 2-Carboxyethyl phosphonic acid (2-CEPA) and Citrate ethylene diamine phosphonic acid (CEDPA) and mixtures thereof.
In one embodiment the organic phosphonic acid has 1-6 phosphonate groups per molecule. In one embodiment molecular weight of the organic phosphonic acid is 100-1000 g/mol, preferably 200-600 g/mol. In one embodiment the organic phosphonic acid preferably comprises HEDP, DTPMP, HEMPA, ATMP and mixtures thereof.
In one embodiment the phosphonate salt of the organic phosphonic acid preferably comprises salts of HEDP, DTPMP, HEMPA, ATMP and mixtures thereof. In one embodiment the phosphonate is partly or completely neutralized. The neutralization can be done with bases, such as sodium, lithium and potassium bases. In one embodiment the phosphonate salt comprises sodium phosphonates, lithium phosphonates and potassium phosphonates.
In one embodiment the molecular weight of the water-soluble binder is 100 kDa- 1000 kDa, preferably 100 kDa-500 kDa, more preferably 100 kDa-400 kDa even more preferably 100 kDa-300 kDa. S 25 In one embodiment functional groups and monomers of the water-soluble binder se comprises carboxylic acids and anhydrides (such as acrylic acid, methacrylic acid, © acetic acid, maleic anhydride, maleic acid, fumaric acid, itaconic acid, aconitic I acid, mesaconic acid, citraconic acid, crotonic acid, isocrotonic acid, angelic acid, < tiglic acid, vinyl acetic acid, hydroxyethyl methacrylic acid (HEMA), hydroxyethyl & 30 acrylic acid (HEA)), sulphonic acid (such as vinyl sulphonic acid, allyl sulphonic N acid, styrene-p-sulphonic acid, acryloamido-2-methylpropanesulfonic acid N (AMPS)), acrylamides (such as terybutylacrylamides), alcohols (such as vinyl alcohol, propargyl alcohol having formula HCEC—CH2— OH: butyr-1,4-diol), vinyl chloride, and salts of any of these groups and mixtures of any of these groups thereof.
In one embodiment functional groups and monomers of the water-soluble binder comprise carboxylic acids and anhydrides, sulphonic acid, acrylamides, alcohols, vinylchloride and salts of any of these groups, and mixtures of any of these groups thereof.
In one embodiment the water-soluble binder comprises homopolymer and/or copolymer of acrylic acid, methacrylic acid, maleic acid, AMPS, acrylamide, styrene-p-sulphonic acid and mixtures thereof.
The water-soluble binder can be in acidic form, or it can be partly or completely neutralized (i.e. 100 % of acid groups are neutralized) e.g. with sodium, lithium or potassium. pH of the water-soluble binder can be selected so that pH of the composition is 7 or close to 7, such as 6-8. In one embodment the water-soluble binder is selected so that pH of the composition is 7 or close to 7 such as 6-8, therefore corrosion of aluminum current collector and leaching/degradation of active material, such as Ni and Li, can be prevented.
In one embodiment the water-soluble binder is polyacrylic acid (PAA) and/or carboxymethyl cellulose (CMC). S 25 se In one embodiment molecular weight (MW) of the PAA is 100 kDa-1000 kDa, © preferably 100 kDa-500 kDa, more preferably 100kDa-400 kDa.
The PAA can be I in acidic form, or it can be partly or completely neutralized e.g. with sodium, lithium < or potassium.
In one embodiment the PAA is partly neutralized and having such & 30 pH that the pH of the water based composition is 7 or close to 7, such as 6-8. 3 In one embodiment the formulation is produced by mixing water, the at least one water-soluble binder and the at least one organic phosphonic acid or at least one phosphonate salt of the organic phosphonic acid or a mixture of at least one organic phosphonic acid and at least one phosphonate salt of the organic phosphonic acid One or more of the above disclosed embodiments can be combined.
In a second aspect the present invention provides a lithium-ion battery cathode composition. The composition comprises at least one cathode active material, at least one electrical conducitivity enhancing additive, at least one water-soluble binder, and at least one organic phosphonic acid or at least one phosphonate salt of the organic phosphonic acid or a mixture of the at least one organic phosphonic acid and the at least one phosphonate salt of the organic phosphonic acid. In one embodiment solvent of the composition is polar solvent. In one embodiment the composition is aqueous (water) based composition. In one embodiment solvent of the composition is organic. The composition may comprise compounds having aromatic groups and/or halogenated compounds. In one embodiment the cathode active material comprises lithium nickel manganese cobalt oxides (NMC LiNixMnyC0ozO2), lithium ferro phosphate (LFP, LiFePO4), lithium cobalt oxide (LCO, LiCoO2), lithium manganese oxide (LMO, S 25 LiMn2094), lithium nickel cobalt aluminum oxide (LiNiCoAIO2), lithium titanate se (LTO, Li2TiO3) and mixtures thereof. 2 I In one embodiment the electrical conducitivity enhancing additive comprises a < carbon nanotube, graphene, carbon black, activated carbon and mixture thereof. & 30 N In one embodiment the composition comprises, optionally, at least one thickening N agent, e.g. carbohydrate type polymer such as carboxymethyl cellulose, CMC,
xanthan gum or quar gum (to increase the viscosity of the composition (slurry) and to prevent the solvent — solid particles phase separation). In one embodiment the organic phoshonic acid comprises Amino Trimethylene Phosphonic Acid (ATMP) CAS No. 6419-19-8, 1-Hydroxy Ethylidene-1,1- Diphosphonic Acid (HEDP) CAS No. 2809-21-4, Ethylene Diamine Tetra (Methylene Phosphonic Acid) (EDTMPA) CAS No 1429-50-1, Diethylene Triamine Penta (Methylene Phosphonic Acid) (DTPMPA) CAS No. 15827-60-8, 2-Phosphonobutane -1,2,4-Tricarboxylic Acid (PBTC) CAS No. 37971-36-1, 2- Hydroxy Phosphonoacetic — Acid (HPAA) CAS No. 23783-26-8, HexaMethyleneDiamineTetra (MethylenePhosphonic Acid) (HMDTMPA) CAS No. 23605-74-5, Hydroxyethylamino-Di(Methylene Phosphonic Acid) (HEMPA) CAS No. 5995-42-86, Triethylene-tetramine Hexmethanephonic Acid (TETHMP), Polyamino Polyether Methylene Phosphonic Acid (PAPEMP), Bis(HexaMethylene — Triamine Penta (Methylene Phosphonic Acid) (BHMTPMP) CAS No. 34690-00-1, ethyl phosphonic acid (EPA), (2-aminoethyl)phosphonic acid, 2-chloro- ethylphosphonic acid, 2-Carboxyethyl phosphonic acid (2-CEPA) and Citrate ethylene diamine phosphonic acid (CEDPA) and mixtures thereof. In one embodiment the organic phosphonic acid has 1-6 phosphonate groups per molecule. In one embodiment molecular weight of the organic phosphonic acid is 100-1000 g/mol, preferably 200-600 g/mol. S 25 se In one embodiment the organic phosphonic acid preferably comprises HEDP, © DTPMP, HEMPA, ATMP and mixtures thereof.
E - In one embodiment the phosphonate salt of the organic phosphonic acid preferably & 30 comprises salts of HEDP, DTPMP, HEMPA, ATMP and mixtures thereof. 3
In one embodiment the phosphonate is partly or completely neutralized. The neutralization can be done with bases, such as sodium, lithium and potassium bases. In one embodiment the phosphonate salt comprises sodium phosphonates, lithium phosphonates and potassium phosphonates. In one embodiment the molecular weight of the water-soluble binder is 100 kDa- 1000 kDa, preferably 100 kDa-500 kDa, more preferably 100 kDa-400 kDa even — more preferably 100 kDa-300 kDa. In one embodiment functional groups and monomers of the water-soluble binder comprises carboxylic acids and anhydrides (such as acrylic acid, methacrylic acid, acetic acid, maleic anhydride, maleic acid, fumaric acid, itaconic acid, aconitic acid, mesaconic acid, citraconic acid, crotonic acid, isocrotonic acid, angelic acid, tiglic acid, vinyl acetic acid, hydroxyethyl methacrylic acid (HEMA), hydroxyethyl acrylic acid (HEA)), sulphonic acid (such as vinyl sulphonic acid, allyl sulphonic acid, styrene-p-sulphonic acid, acryloamido-2-methylpropanesulfonic acid (AMPS)), acrylamides (such as terybutylacrylamides), alcohols (such as vinyl alcohol, propargyl alcohol having formula HCEC—CH2— OH: butyr-1,4-diol), vinyl chloride, and salts of any of these groups and mixtures of any of these groups thereof. In one embodiment functional groups and monomers of the water-soluble binder S 25 comprise carboxylic acids and anhydrides, sulphonic acid, acrylamides, alcohols, se vinylchloride and salts of any of these groups, and mixtures of any of these groups © thereof. j - In one embodiment the water-soluble binder comprises homopolymer and/or & 30 copolymer of acrylic acid, methacrylic acid, maleic acid, AMPS, acrylamide, N styrene-p-sulphonic acid and mixtures thereof.
N
The water-soluble binder can be in acidic form, or it can be partly or completely neutralized (i.e. 100 % of acid groups are neutralized) e.g. with sodium, lithium or potassium. pH of the water-soluble binder can be selected so that pH of the composition is 7 or close to 7, such as 6-8.
In one embodment the water-soluble binder is selected so that pH of the composition is 7 or close to 7 such as 6-8, therefore corrosion of aluminum current collector and leaching/degradation of active material, such as Ni and Li, can be prevented.
In one embodiment the water-soluble binder is polyacrylic acid (PAA) and/or carboxymethyl cellulose (CMC). In one embodiment molecular weight (MW) of the PAA is 100 kDa-1000 kDa, preferably 100 kDa-500 kDa, more preferably 100kDa-400 kDa. The PAA can be in acidic form, or it can be partly or completely neutralized e.g. with sodium, lithium or potassium. In one embodiment the PAA is partly neutralized and having such pH that the pH of the water based composition is 7 or close to 7, such as 6-8. In one embodiment the cathode slurry comprises 20-60 wt.%, preferably 40-60 wt. % solids fraction. In one embodiment the solids fraction comprises 70-95 wt. %, preferably 80-95 wt. % of the cathode active material. S 25 se In one embodiment the solids fraction comprises 1-15 wt.%, preferably 2-10 wt.%, © more preferably 2-5 wt.% of the electrical conducitivity enhancing additive.
E - In one embodiment the solid fraction comprises 1-15 wt.%, preferably 2-8 wt.% of & 30 the water-soluble binder formulation consisting of water-soluble binder and N organic phosphonic acid and/or phosphonate salt of the organic phosphonic acid.
N
In one embodiment the binder formulation comprises 1-50 wt.%, preferably 1-25 wt%, more preferably 1-10 wt.% of the phosphonic acid and/or the phosphonate salt of the organic phosphonic acid.
In one embodiment dry fraction (solids) in the electrode consists the cathode active material : the binder and the organic phosphonic acid and/or the salt of phosphonic acid : the electrical conductivity enhancing agent in weight fractions of 95: 3 : 2 (wt.%), respectively.
In one embodiment solids loading in the electrode is 20-60 %, preferably 40-60 %. In one embodiment range of weight fraction of the binder : the organic phosphonic acid and/or the salt of phosphnic acid in the composition is 50:50 to 99:1.
The weight fractions are calculated as weight fractions of active coponent. In one embodiment weight fractions of the water-soluble binder and the phosphonic acid and/or the phosphonate salt of the organic phosphonic acid are at least 50 wt.% water-soluble binder and less than 50 wt.% phosphonic acid and/or the phosphonate salt of the organic phosphonic acid, preferably at least 75 wt.% water-soluble binder and less than 25 wt.% phosphonic acid and/or the phosphonate salt of the organic phosphonic acid. O 25 Oneormore of the above disclosed embodiments can be combined.
O <Q © In a third aspect the present invention provides an electrode for a lithium-ion battery I comprising an aluminum current collector and at least one active material layer on 3 at least one surface of the aluminum current collector, wherein the at least one active & 30 material layer is formed from the cathode composition according to the present N invention.
N
In a fourth aspect the present invention provides a method for producing a lithium- ion battery cathode composition, wherein the method comprises mixing water, at least one electrical conducitivity enhancing additive, at least one water-soluble binder, and at least one organic phosphonic acid or at least one phosphonate salt of the organic phosphonic acid or a mixture of the at least one organic phosphonic acid and the at least one phosphonate salt of the organic phosphonic acid and optionally at least one thickening agent for producing a mixture, followed by adding at least one cathode active material to the mixture.
In one embodiment the electrical conducitivity enhancing additive, the water- soluble binder, the phosphonic acid, the phoshonate salt of the organic phosphonic acid and the cathode active material are the same as defined above. In a preferred embodiment, the method of the present invention produces the composition for lithium-ion battery cathode according to the present invention.
In a fifth aspect the present invention provides a method for producing an electrode for a lithium-ion battery cathode, wherein the method comprises mixing water, at least one electrical conducitivity enhancing additive, at least one water-soluble binder, and at least one organic phosphonic acid or at least one phosphonate salt of the organic phosphonic acid or a mixture of the at least one organic phosphonic acid and the at least one phosphonate salt of the organic phosphonic acid and optionally at least one thickening agent, followed by adding at least one cathode active material to the mixture for producing a composition (slurry), followed by S 25 coating an aluminum current collector with the slurry and drying the coated se aluminum current collector.
2 I The coating of the aluminum current collector can be performed by any suitable a < method known for a skilled person. Such methods for example comprises slot- & 30 die, blade, roll-to-roll and gravure coating technologies.
3
The drying of the coated aluminum current collector can be performed by any suitable method known for a skilled person. Such methods for example comprises industrial dryer, oven drying and vacuum drying.
In one embodiment the electrical conducitivity enhancing additive, the water- soluble binder, the phosphonic acid, the phoshonate salt of the acid and the cathode active material are the same as defined above.
In a preferred embodiment, the method of the present invention produces the electrode for lithium-ion battery cathode according the present invention. In a sixth aspect the present invention provides a lithium-ion battery comprising the electrode for a lithium-ion battery according to the present invention In a seventh aspect the present invention provide use of the lithium-ion battery cathode composition according to the present invention for an electrode for a lithium-ion battery.
EXAMPLES Example 1 — reference slurry with PVDF/NMP binder 5-10 w-% polyvinylidene fluoride (PVDF) in N-methylpyrrolidone (NMP) solvent is prepared by dissolving first the polymer to solvent. The dried carbon (Timcal C65) is added to PVDF solution and mixing is continued for 30-60 min. The dried O lithium nickel manganese cobalt oxide active material (type NMC622, Targray is se 25 added in 2-4 parts. Mixture is stirred for 30-60 minutes between each addition. 2 Viscosity is checked after mixing and more NMP is added if needed. The slurry is I let to stand for 30-60 min to remove most of the bubbles formed during mixing. 3 The slurry is coated with DoctorBlade to Al foild. 120-200 um wet thicknesses & have been used to achieve 1 mAh cm? (~5 mg cm? of active material). The N 30 coated foils are dried in a fume hood overnight, after which the foils are dried in N an oven at 80 *C for 4 h. The electrodes are cut and calandered using 2.5 t/cm? force.
Example 2 — general composition of aqueous cathode slurry Aqueous binder cathode slurry is formed by first mixing water solvent, the carbon black conductive additive (Timcal C65) and binder together.
After this, lithium nickel manganese cobalt oxide active material (type NMC622, Targray) is added to the mixture.
The dry weight fraction of the slurry is 30-35 w-% and the dry fraction of the slurry consits of NMC active material: binder+dispersion agent : conductive additive in weight fractions of 95 : 3 : 2, respectively.
Aluminum current collector is coated with well-mixed, homogeneous cathode slurry.
The coating is done on Al foil either manually using metallic rolling pin or using Doctor Blade.
In the case of Doctor Blade coating, 120-200 um wet thicknesses have been used to achieve 1 mAh cm”? (~5 mg cm”? of active material). Usually 170 um is the most suitable.
The cathode is dried (first 2 h at 80 °C, cut and calendared using 2.5 t/cm? force.
Finally, the cut electrodes are dried overnight either 120 °C in a vacuum oven or 140 °C in a heating cabinet.
Example 3 —reference slurry containing PAA binder Used binder is acidic polyacrylic acid or partly sodium neutralized polyacrylic acid (PAA, molecular weight appr. 250-280 kDa). The dry fraction of the slurry consits of NMC : PAA binder : conductive additive (C) in weight fractions of 95 : 3 : 2, respectively.
Example 4 — slurry composition with PAA and HEDP according to the present invention S 25 Used binder is partly sodium neutralized PAA (MW appr. 250 kDa) and se phosphonic acid is 1-Hydroxyethane-1,1-diphosphonic acid (HEDP). The weight O fractions of NMC: binder + HEDP: C are 95:3:2, respectively.
The weight fractions I of binders:HEDP vary from 50:50 to 90:10, respectively. > N 30 OPTICAL MICROSCOPY N Figure 1a and 1b present optical microscopy images of electrodes composed of NN slurrs of reference Example 3 and Example 4 according to the present invention.
In these samples, dry weight fraction of the slurries was 30 w-%. After slurry formation, the samples are coated to Al foil manually using metallic rolling pin and dried in a heating cabinet at 140 °C overnight. The dried electrodes are calendared using 2.5 t/cm? force.The samples are imaged using Leica DMLM microscope with LAS-X software using 10x magnification, 5.0 brightness, 1.0 contrast and white light. Binder and/or phosphonic acid/phosphonate additive used in the NMC622 cathodes: Fig. 1a: PAA binder (Ref. Example 3); Fig. 1b: PAA + HEDP, PAA:HEDP weight fractions 80:20 (Example 4 according to the present invention).
GALVANOSTATIC RATE CAPABILITY MEASUREMENTS Figure 2 presents the results of rate capability measurements of LiBs (lithium on batteries) composed of cathode slurries of Ref. Examples 1 and 3 and Example 4 of the present invention. Cathodes of (lithium ion batteries) LiBs are prepared by coating the sample to Al foil using Doctor Blade technique and drying the electrodes in a vacuum oven overnight at 120 °C. In the case of PVDF/NMP cathode, the electrodes are dried in an oven at 80 °C for 4 h. In aqueous cathode compositions, dry weight fraction of the electrodes is 35 w-%, whereas in PVDF/NMP cathode the dry weight fraction is 60 w-%. The dry weight fractions of all cathodes consist of NMC active material:binder+dispersion agent:conductive additive in 95:3:2 weight fractions. N 25 Cathodes are assembled as half cells (2016 Hohsen coin cells, 2 20 mm, 1.6 mm N thickness) for galvanostatic rate capability measurements. Glass fiber separator = (Whatman GF/A, 0.26 mm), 0.75 mm thick lithium metal counter electrode (Alfa 7 Aesar), 0.2 mm thick stainless steel spacer (MTI) and 1 M LiPF4 in 1:1 EC:DMC & (BASF, LP30) have been used for the half cell assembly. & 30 = The electrochemical measurements were started 24 h after cell assembly. The i galvanostatic rate capability measurements are done with Neware battery cycler. Rate capabilities of the Li half-cells are measured in voltage ranges of 3-4.4 V by varying discharge C-rates from 0.2 C to 5.0 C while retaining the charge C-rate constant at 0.2 C. Formation cycle (cycle 0) is done with C rate of 1/30. At least three parallel measurements are carried out of similar electrode structure to ensure the repeatability of the results. Figure 2 presents average results of these parallel measurements. The average specific discharge capacity of LiB half cell composed of cathode with PAA binder and HEDP in weight fractions of 9:1 is 16-37% higher than that of cathode with only PAA binder without phoshonic acid additive. The difference between the specific capacities depends on the PAA binder type (250 kDa, pH
3.5-4.5 or 280 kDa, pH 1.5-1.8) cycle number and the C-rate. C-rate has a notable impact on the discharge capacities of the cells: the cathode composed of PAA+HEDP has 16-18% higher discharge capacity than that of cathode without phosphonic acid additive at low/moderate C-rates of 0.1-1C, whereas the — difference is 34-37% with the highest C-rate of 5. In the last three cycles with 0.1C rate, the difference between the discharge capacities of PAA+HEDP and cell without HEDP additive is 22%, indicating that HEDP additive improves the cycling stability of the cell. Cell with aqueous PAA binder + HEDP additive has also 3-9% higher discharge capacity as compared to that of PVDF/NMP cell. The difference between discharge capacities of PAA+HEDP and PVDF/NMP cell increases, again, as a function of C-rate and cycle number, indicating that the aqueous binder+phosphonic acid/phosphonate composition has better stability than that of PVDF/NMP and that phosphonate composition performs better when the lithiation/delithiation kinetics are faster. S 25 se Figure 3. presents relative average specific discharge capacities of LiB half-cells O composed of NMC622 with varying binder/additive composition as a function of I cycle number. C-rate in each cycle (0.1-5C) is shown in the Figure 3. PVDF in < NMP cathode is prepared according to Ref. Example 1, PAA binders according to & 30 Ref. Example 3 and PAA+HEDP 9:1 cathode according to Example 4 of the N present invention.
N
Relative average specific discharge capacities of the cells are calculated as the ratio of discharge capacity in the cycle and the initial average discharge capacity (average of the discharge capacity of the cell in the cycles 1-3 with C-rate of 0.1). The relative capacity describes thus how the capacity decreases as a function of increasing C-rate and cycle number. The cell with cathode composition containing PAA binder and HEDP additive has 1-3% lower relative discharge capacity than those of cells with only PAA binder in cycles with 0.2 - 1C-rate, but the difference between the relative discharge capacities decreases upon increasing C-rate and cycle number. In the cycles with C-rate of 5, PAA+HEDP cell has 13-14% higher relative discharge capacity than those of PAA binder samples without phosphonate additive, and in the last three cycles with low C-rate of 0.1C, the cell with PAA+HEDP has 1-2% higher relative discharge capacity than those of PAA cells without HEDP. PAA+HEDP cell has also 3% higher relative discharge capacity than that of PVDF/NMP cell in the last three cycles. The high relative — capacity in the last cycles indicate that the cathode with phosphonate composition has better cycling stability as compared to other tested cathode compositions. Various embodiments have been presented. It should be appreciated that in this document, words comprise, include, and contain are each used as open-ended expressions with no intended exclusivity.
The foregoing description has provided by way of non-limiting examples of particular implementations and embodiments a full and informative description of the best mode presently contemplated by the inventors for carrying out the invention. It is however clear to a person skilled in the art that the invention is not restricted to N details of the embodiments presented in the foregoing, but that it can be N 25 implemented in other embodiments using eguivalent means or in different = combinations of embodiments without deviating from the characteristics of the 7 invention.
T 3 Furthermore, some of the features of the afore-disclosed example embodiments & may be used to advantage without the corresponding use of other features. As such, 3 30 the foregoing description shall be considered as merely illustrative of the principles of the present invention, and not in limitation thereof. Hence, the scope of the invention is only restricted by the appended patent claims.

Claims (15)

1. A lithium-ion battery cathode binder formulation comprising at least one water- soluble binder and at least one organic phosphonic acid or at least one phosphonate salt of the organic phosphonic acid or a mixture of at least one organic phosphonic acid and at least one phosphonate salt of the organic phosphonic acid.
2. The binder formulation according to claim 1, wherein the binder formulation comprises 1-50 wt.%, preferably 1-25 wt%, more preferably 1-10 wt.% of the organic phosphonic acid or the phosphonate salt of the organic acid or a mixture of at least one organic phosphonic acid and at least one phosphonate salt of the organic phosphonic acid.
3. A lithium-ion battery cathode composition comprising at least one cathode active material, at least one electrical conducitivity enhancing additive, at least one water-soluble binder, and at least one organic phosphonic acid or at least one phosphonate salt of the organic phosphonic acid or a mixture of at least one organic phosphonic acid and at least one phosphonate salt of the organic phosphonic acid.
4. The composition according to claim 3, wherein the cathode active material comprises lithium nickel manganese cobalt oxides (NMC LiNixMnyC0ozO2), = lithium ferro phosphate (LFP, LiFePO4), lithium cobalt oxide (LCO, LiCo02), N 25 lithium manganese oxide (LMO, LiMn204), lithium nickel cobalt aluminum 3 oxide (LiNiCoAlO2), lithium titanate (LTO, Li2TiO3) and mixtures thereof. 3 E
5. The composition acording to claim 3 or 4, wherein electrical conducitivity 3 enhancing additive comprises carbon nanotube, graphene, carbon black, © 30 activated carbon and mixtures thereof.
6. The composition acording to any of claims 3-5, wherein the organic phosphonic acid comprises Amino Trimethylene Phosphonic Acid (ATMP), 1-
Hydroxy Ethylidene-1,1-Diphosphonic Acid (HEDP), Ethylene Diamine Tetra (Methylene Phosphonic Acid) (EDTMPA), Diethylene Triamine Penta (Methylene Phosphonic Acid) (DTPMPA) 2-Phosphonobutane-1,2 4- Tricarboxylic Acid (PBTC), 2-Hydroxy Phosphonoacetic Acid (HPAA), HexaMethyleneDiamineTetra (MethylenePhosphonic Acid) (HMDTMPA), Hydroxyethylamino-Di(Methylene Phosphonic Acid) (HEMPA), Triethylene- tetramine Hexmethanephonic Acid (TETHMP) Polyamino Polyether Methylene Phosphonic Acid (PAPEMP), Bis(HexaMethylene Triamine Penta (Methylene Phosphonic Acid) (BHMTPMP), Ethyl phosphonic acid (EPA), (2- aminoethyl)phosphonic acid, 2-chloroethylphosphonic acid, 2-Carboxyethyl phosphonic acid (2-CEPA) and Citrate ethylene diamine phosphonic acid (CEDPA) and mixtures thereof.
7. The composition acording to any of claims 3-6, wherein functional groups and monomers of the water-soluble binder comprise carboxylic acids and anhydrides, sulphonic acid, acrylamides, alcohols, vinylchloride and salts of any of these groups, and mixtures of any of these groups thereof.
8. The composition acording to any of claims 3-7, wherein the water-soluble binder comprises homopolymer and/or copolymer of acrylic acid, methacrylic acid, maleic acid, AMPS, acrylamide, styrene-p-sulphonic acid and mixtures thereof.
_ 25 9. The composition acording to any of claims 3-8, wherein the molecular weight O of the water-soluble binder is 100 kDa-1000 kDa, preferably 100 kDa-500 kDa, se more preferably 100 kDa-450 kDa.
2 E 30 10. The composition acording to any of claims 3-9, wherein weight fractions of the 3 water-soluble binder and the phosphonic acid and/or the phosphonate salt are © at least 50 wt.% water-soluble binder and less than 50 wt.% phosphonic acid O and/or the phosphonate salt, preferably at least 75 wt.% water-soluble binder and less than 25 wt.% phosphonic acid and/or the phosphonate salt.
11. An electrode for a lithium-ion battery comprising an aluminum current collector and at least one active material layer on at least one surface of the aluminum current collector, wherein the at least one active material layer is formed from the lithium-ion battery cathode composition according to any of claims 3-10.
12. A method for producing a lithium-ion battery cathode composition, wherein the method comprises mixing water, at least one electrical conducitivity enhancing additive, at least one water-soluble binder and at least one organic phosphonic acid or at least one phosphonate salt of the organic phosphonic acid or a mixture of at least one organic phosphonic acid and at least one phosphonate salt of the organic phosphonic acid and optionally at least one thickening agent for producing a mixture, followed by adding at least one cathode active material to the mixture.
13. A method for producing an electrode for a lithium-ion battery cathode, wherein the method comprises mixing water, at least one electrical conducitivity enhancing additive, at least one water-soluble binder and at least one organic phosphonic acid or at least one phosphonate salt of the organic phosphonic acid or a mixture of at least one organic phosphonic acid and at least one phosphonate salt of the organic phosphonic acid and optionally at least one thickening agent, followed by adding at least one cathode active material to the mixture for producing a composition (slurry), followed by coating an aluminum current collector with the slurry and drying the coated aluminum current collector.
S 25 se
14. A lithium-ion battery comprising the electrode for a lithium-ion battery according © to claim 11.
E <
15. Use of the lithium-ion battery cathode composition according to any of claims 3- & 30 10 for an electrode for a lithium-ion battery.
3
FI20215234A 2021-03-03 2021-03-03 Composition for lithium-ion battery cathode FI20215234A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
FI20215234A FI20215234A1 (en) 2021-03-03 2021-03-03 Composition for lithium-ion battery cathode
PCT/FI2022/050132 WO2022184980A1 (en) 2021-03-03 2022-02-28 Composition for lithium-ion battery cathode

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FI20215234A FI20215234A1 (en) 2021-03-03 2021-03-03 Composition for lithium-ion battery cathode

Publications (1)

Publication Number Publication Date
FI20215234A1 true FI20215234A1 (en) 2022-09-04

Family

ID=80684069

Family Applications (1)

Application Number Title Priority Date Filing Date
FI20215234A FI20215234A1 (en) 2021-03-03 2021-03-03 Composition for lithium-ion battery cathode

Country Status (2)

Country Link
FI (1) FI20215234A1 (en)
WO (1) WO2022184980A1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023149402A1 (en) * 2022-02-03 2023-08-10 東ソー株式会社 Water-soluble chelating polymer and method for producing same

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5652313B2 (en) * 2011-04-28 2015-01-14 日本ゼオン株式会社 Negative electrode slurry composition for lithium secondary battery, method for producing negative electrode for lithium secondary battery, negative electrode for lithium secondary battery, and lithium secondary battery
EP2889335B1 (en) * 2012-08-21 2017-02-01 Dainichiseika Color & Chemicals Mfg. Co., Ltd. Aqueous liquid composition, aqueous coating liquid, functional coating film and composite material
JPWO2015146649A1 (en) * 2014-03-24 2017-04-13 昭和電工株式会社 Slurry for positive electrode of lithium ion secondary battery, positive electrode obtained using this slurry and method for producing the same, lithium ion secondary battery comprising this positive electrode and method for producing the same
CN105645611A (en) * 2016-02-03 2016-06-08 青岛科润生物科技有限公司 Multifunctional industrial water disposal agent and preparing method thereof
WO2020198982A1 (en) * 2019-03-29 2020-10-08 Kemira Oyj Dispersant composition, method for controlling, preventing and/or reducing formation of inorganic scale and deposits, and use of composition

Also Published As

Publication number Publication date
WO2022184980A1 (en) 2022-09-09

Similar Documents

Publication Publication Date Title
JP6094840B2 (en) Lithium ion secondary battery
US10950865B2 (en) Negative electrode agent for nonaqueous electrolyte secondary battery, negative electrode for nonaqueous electrolyte secondary battery, and nonaqueous electrolyte secondary battery
WO2016035289A1 (en) Negative electrode for nonaqueous electrolyte secondary batteries, and nonaqueous electrolyte secondary battery
KR101534386B1 (en) Non-aqueous secondary battery having a blended cathode active material
US9722251B2 (en) Binder composition for secondary battery, cathode and lithium battery including the binder composition
KR20230007337A (en) Conductive material dispersion and its manufacturing method, and composition for secondary battery electrode using the same, electrode film, secondary battery, vehicle
US20120028117A1 (en) Fluorinated binder composite materials and carbon nanotubes for positive electrodes for lithium batteries
KR20130081055A (en) Positive electrode material for lithium battery, positive material prepared from the material, and lithium battery including the positive electrode
CN104303356A (en) Low cost Si-based negative electrodes with enhanced cycling performance
JP6213315B2 (en) Composition comprising surface-treated positive electrode active material, dispersant and solvent
US20190379049A1 (en) Binder for electrochemical element
US20210328225A1 (en) Negative electrode and secondary battery including the same
JP7031655B2 (en) Binder composition for non-aqueous secondary battery electrode, conductive material paste composition for non-aqueous secondary battery electrode, slurry composition for non-aqueous secondary battery electrode, non-aqueous secondary battery electrode and non-aqueous secondary battery
US20090311600A1 (en) Negative electrode for nonaqueous electrolyte secondary battery, nonaqueous electrolyte secondary battery including the same and method for fabrication of negative electrode for nonaqueous electrolyte secondary battery
KR20180013037A (en) Binder composition for lithium secondary battery, electrode for lithium secondary battery including the same, and lithium secondary battery including the electrode
WO2017150048A1 (en) Binder composition for non-aqueous secondary cell electrode, electrically conductive material paste composition for non-aqueous secondary cell electrode, slurry composition for non-aqueous secondary cell electrode, electrode for non-aqueous secondary cell, and non-aqueous secondary cell
WO2022184980A1 (en) Composition for lithium-ion battery cathode
JP7373733B2 (en) Negative electrode for non-aqueous electrolyte secondary batteries
US11329278B2 (en) Process to prepare an electrode for an electrochemical storage device
JP6136849B2 (en) Positive electrode containing surface-modified active material and high-resistance metal compound
US10840514B2 (en) Aqueous binder for lithium-sulfur secondary battery, preparation method thereof and lithium-sulfur secondary battery comprising the same
JP2022002188A (en) Separator for lithium ion battery
WO2022184979A1 (en) Lithium-ion battery cathode binder formulation
JP6831699B2 (en) Current collector for lithium-ion batteries
WO2020137403A1 (en) Carbon material dispersion liquid for secondary battery electrodes, slurry composition for secondary battery electrodes, electrode for secondary batteries, and secondary battery