Lithium-ion battery with a negative electrode based on germanium and the ability to cycle at negative temperatures

Claims

1. An electrode coating for the negative electrode of a lithium-ion battery with a specific energy of more than 200 Wh / kg, consisting of a carbon conductive additive, a polymer binder and germanium (Ge) nanofibers, with a mass loading of more than 5 mg per cm 2 substrates.

2. The coating according to paragraph 1, characterized in that the mass fraction of germanium (Ge) nanofibers is from 70% to 95%.

3. The coating according to paragraph 1, characterized in that carbon black, soot, activated carbon, graphite, graphene, a graphene derivative, carbon nanotubes, chemically modified carbon nanotubes, or a mixture thereof are used as the conductive additive.

4. The coating according to claim 1, characterized in that the polymer binder used is a polymer binder selected from the group consisting of polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, polyethylene oxide, styrene-butadiene rubber, carboxymethyl cellulose, polyvinylidene fluoride-hexafluoropropylene, a cellulose-based compound, or a mixture thereof.

5. A negative electrode for a lithium-ion battery, which is a metal current collector with an electrode coating applied to it in a roll-type manner according to paragraph 1.

6. A negative electrode according to paragraph 5, characterized in that the roll method is a slot extrusion method or an applicator method of applying pastes.

7. The negative electrode according to paragraph 5, characterized in that the current collector is made of copper, titanium, an electrically conductive polymer, carbon paper, and a mixture thereof.

8. The negative electrode according to paragraph 5, characterized in that the layer thickness is from 50 to 250 µm.

9. A lithium-ion battery with a specific energy of more than 200 Wh / kg and the ability to cycle at temperatures below minus 10°C with a Coulomb efficiency of at least 98%, consists of an electrode block consisting of a positive electrode, a negative electrode and a separator placed between them, a current source housing in which the electrode block is placed, a non-aqueous electrolyte solution wetting the positive and negative electrodes and the separator.

10. A lithium-ion battery according to claim 9, characterized in that the electrode block has a rolled coaxial structure formed by rolling a positive electrode, a negative electrode, and a separator around an axis, or a stack structure formed by alternatingly stacking a positive electrode, a separator, and a negative electrode on top of each other.

11. A lithium-ion battery according to claim 9, characterized in that a polymer membrane made of polyethylene, polypropylene, polyester, polyacetal, polyimide, polyetheretherketone, polyphenylene oxide, polyphenylene sulfide, polyethylene naphthalate, polyethylene oxide or a mixture thereof is used as a separator.

12. A lithium-ion battery according to claim 9, characterized in that the positive electrode contains an active material selected from the group consisting of lithium iron phosphate (LiFePO4), lithium cobaltate (LiCoO2), lithium manganese spinel (LiMnO2), lithium manganese phosphate (LiMnPO4), and layered transition metal oxides described by the structural formula LiNi x Mn y Co 1-x-y O 2.

13. A lithium-ion battery according to claim 9, characterized in that the non-aqueous electrolyte solution includes an organic aprotic solvent and a lithium salt.

14. A lithium-ion battery according to claim 13, characterized in that the organic aprotic solvent is selected from the group consisting of ethylene carbonate, propylene carbonate, vinylene carbonate, vinylethylene carbonate, fluoroethylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, γ-butyrolactone, or a mixture thereof.

15. The lithium-ion battery of claim 13, wherein the lithium salt is a lithium salt selected from the group consisting of lithium hexafluorophosphate (LiPF6), lithium perchlorate (LiClO4), lithium tetrafluoroborate (LiBF4), lithium difluoro(oxalato)borate (LiDFOB), lithium bis(oxalato)borate (LiBOB), lithium bis-fluorosulfonylimide (LiFSI), lithium bis-trifluorosulfonylimide (LiTFSI) and mixtures thereof.

16. A lithium-ion battery according to claim 9, characterized in that the housing is made of a material selected from the group including aluminum, stainless steel, nickel, multilayer aluminum laminated foil, or a mixture thereof.