Modified Current Collector for Secondary Battery

Patent metadata

Field	Value
Publication number	US-2025046824-A1
Application number	US-202118714562-A
Country	US
Kind code	A1
Filing date	Dec 16, 2021
Priority date	Dec 2, 2021
Publication date	Feb 6, 2025
Grant date	—

Abstract

Provided herein is a modified current collector for a secondary battery, comprising a substrate and a conductive layer applied on one side or both sides of the substrate, wherein the conductive layer comprises a conductive material, a particulate material, and binder material, wherein the binder material comprises a copolymer. Also provided herein is an electrode for a secondary battery, comprising the modified current collector and an electrode layer, wherein the electrode layer is located on the surface of the conductive layer(s). Within an electrode comprising the modified current collector, the presence of the conductive layer inhibits corrosion of the substrate and reduces interfacial resistance between the electrode layer and the substrate. Consequently, batteries comprising an electrode prepared using the modified current collector disclosed herein exhibit exceptional electrochemical performance.

First claim

What is claimed is:

1 . A modified current collector for a secondary battery, comprising a substrate and a conductive layer applied on one side or both sides of the substrate, wherein the conductive layer comprises a conductive material, a particulate material, and a binder material, wherein the binder material comprises a copolymer comprising a structural unit (a), wherein the structural unit (a) comprises one or more monomeric unit(s) with formula (1):

and wherein each of R 1 , R 2 , R 3 and R 4 in formula (1) is independently H, hydroxyl, alkyl, hydroxyalkyl, halogen, or alkyl halide.

2 . The modified current collector of claim 1 , wherein the copolymer further comprises a structural unit (b), wherein the structural unit (b) comprises one or more monomeric unit(s) with formula (2):

and wherein each of R 5 , R 6 , R 7 and R 8 in formula (2) is independently H, alkyl, acyloxy, acyloxyalkyl, halogen, or alkyl halide.

3 . The modified current collector of claim 1 , wherein the proportion of the structural unit (a) in the copolymer is at least 90% by mole, based on the total number of moles of monomeric units in the copolymer.

4 . The modified current collector of claim 1 , wherein the proportion of the structural unit (a) in the copolymer is from about 90% to about 99.8% by mole, based on the total number of moles of monomeric units in the copolymer.

5 . The modified current collector of claim 2 , wherein the proportion of the structural unit (b) in the copolymer is from about 0.1% to about 10% by mole, based on the total number of moles of monomeric units in the copolymer.

6 . The modified current collector of claim 2 , wherein the molar ratio of structural unit (a) to structural unit (b) in the copolymer is from about 9 to about 1000.

7 . The modified current collector of claim 1 , wherein the modified collector has a thickness of from about 5 m to about 70 m.

8 . The modified current collector of claim 1 , wherein the substrate is selected from the group consisting of stainless steel, titanium, nickel, aluminum, copper, platinum, gold, silver, chromium, zirconium, tungsten, molybdenum, silicon, tin, vanadium, zinc, cadmium, and alloys thereof, electrically-conductive resin, and combinations thereof.

9 . The modified current collector of claim 1 , wherein the conductive material is selected from the group consisting of carbon, carbon black, graphite, expanded graphite, graphene, graphene nanoplatelets, carbon fibers, carbon nano-fibers, graphitized carbon flake, carbon tubes, carbon nanotubes, activated carbon, Super P, KS6, vapor grown carbon fibers (VGCF), mesoporous carbon, and combinations thereof.

10 . The modified current collector of claim 1 , wherein the particulate material is selected from the group consisting of Fe 2 O 3 , Fe 3 O 4 , FeO(OH), MnO 2 , Al 2 O 3 , AlO(OH), ZnO, La 2 O 3 , CeO 2 , RuO 2 , SiO 2 , TiO 2 , ZrO 2 , Mg(OH) 2 , MgO, SnO 2 , CaCO 3 , BaSO 4 , TiN, AlN, Na 2 O·mTiO 2 , K 2 O·nTiO 2 , BaO x , MTiO 3 , and combinations thereof; wherein m is 3 or 6; n is 1, 2, 4, 6, or 8; x is 1 or 2; and M is Ba, Sr, or Ca.

11 . The modified current collector of claim 2 , wherein the weight-average molecular weight of the copolymer is from about 10,000 g/mol to about 300,000 g/mol.

12 . The modified current collector of claim 1 , wherein the proportion of the conductive material in the conductive layer is from about 25% to about 75% by weight, based on the total weight of the conductive layer; wherein the proportion of the copolymer in the conductive layer is from about 25% to about 75% by weight, based on the total weight of the conductive layer; and wherein the proportion of the particulate material in the conductive layer is from about 0.5% to about 5% by weight, based on the total weight of the conductive layer.

13 . The modified current collector of claim 1 , wherein the hydroxyalkyl is selected from the group consisting of hydroxymethyl, hydroxyethyl, hydroxypropyl, hydroxy (methyl) propyl, hydroxy (methyl) butyl, and combinations thereof.

14 . The modified current collector of claim 2 , wherein the acyloxyalkyl is selected from the group consisting of acyloxymethyl, acyloxyethyl, acyloxypropyl, acyloxy (methyl) propyl, acyloxy (methyl) butyl, and combinations thereof.

15 . An electrode, comprising the modified current collector of claim 1 and an electrode layer, wherein the electrode layer is located on the surface of the conductive layer, and wherein the electrode layer comprises an electrode active material and a binding agent.

16 . The electrode of claim 15 , wherein the electrode active material is a cathode active material selected from the group consisting of LiCoO 2 , LiNiO 2 , LiNi 1−x M x O 2 , LiNi x Mn y O 2 , LiCo x Ni y O 2 , Li 1+z Ni x Mn y Co 1−x−y O 2 , LiNi x Co y Al z O 2 , LiV 2 O 5 , LiTiS 2 , LiMoS 2 , LiMnO 2 , LiCrO 2 , LiMn 2 O 4 , Li 2 MnO 3 , LiFeO 2 , LiFePO 4 , and combinations thereof, wherein each x is independently from 0.1 to 0.9; each y is independently from 0 to 0.9; each z is independently from 0 to 0.4; and wherein M is selected from the group consisting of Co, Mn, Al, Fe, Ti, Ga, Mg, and combinations thereof.

17 . The electrode of claim 15 , wherein the electrode active material is a cathode active material selected from the group consisting of NaCoO 2 , NaFeO 2 , NaNiO 2 , NaCrO 2 , NaVO 2 , NaTiO 2 , NaFePO 4 , Na 3 V 2 (PO 4 ) 3 , Na 3 V 2 (PO 4 ) 2 F 3 , NMC-type mixed oxides, Prussian blue-type sodium compounds, and combinations thereof.

18 . The electrode of claim 15 , wherein the electrode active material is an anode active material selected the group consisting of natural graphite particulate, synthetic graphite particulate, hard carbon, soft carbon, mesocarbon microbeads (MCMB), Sn particulate, SnO 2 , SnO, Li 4 Ti 5 O 12 particulate, Si particulate, Si-C composite particulate, and combinations thereof.

19 . The electrode of claim 15 , wherein the binding agent comprises a polymer comprising one or more functional group(s) containing a halogen, O, N, S, or a combination thereof.

20 . The electrode of claim 19 , wherein each functional group is independently selected from the group consisting of carboxylic acid, carboxylic acid salt, sulfonic acid, sulfonic acid salt, sulfuric acid, sulfuric acid salt, phosphonic acid, phosphonic acid salt, phosphoric acid, phosphoric acid salt, nitric acid, nitric acid salt, amide, hydroxyl, nitrile, ester, epoxy, —NH 2 , and combinations thereof.

Assignees

• Grst Int Ltd

Inventors

• Ho Kam Piu
• Jiang Yingkai
• Huen Priscilla

Classifications

• H01M4/133

  Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title

• H01M4/136

  Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy · CPC title

• H01M4/131

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M4/666

  in the form of mixed materials (H01M4/668 takes precedence) · CPC title

• H01M4/66

  Selection of materials · CPC title