Electrode for a lithium cell

Patent metadata

Field	Value
Publication number	US-2018175367-A1
Application number	US-201515127657-A
Country	US
Kind code	A1
Filing date	Mar 12, 2015
Priority date	Mar 21, 2014
Publication date	Jun 21, 2018
Grant date	—

Abstract

An electrode, in particular, a cathode, for an electrochemical energy store, in particular, for a lithium cell, including particles having one first lithiatable active material, which is based on a transition metal oxide, wherein the particles or a base body including the particles is/are provided with at least one functional layer, which is lithium ion-conductive and includes at least one redox-active element. An energy store including such an electrode, and a method for manufacturing such an electrode, are also described.

First claim

1 - 12 . (canceled)

13 . An electrode for an electrochemical energy store, including particles having a first lithiatable active material, which is based on a transition metal oxide, wherein at least one of the particles and a base body including the particles is provided at least partly with a functional layer which is lithium ion-conductive and includes at least one redox-active element.

14 . The electrode as recited in claim 13 , wherein the first lithiatable active material is based on a general chemical formula (Li(Ni x Co y Mn 1-x-y )O 2 , x being in the range of greater than or equal to 0 to less than or equal to 1 and y in the range of greater than or equal to 0 to less than or equal to 1.

15 . The electrode as recited in claim 14 , wherein x is in the range of greater than or equal to 0.2 to less than or equal to 0.8 and y in the range of greater than or equal to 0 to less than or equal to 0.5.

16 . The electrode as recited in claim 15 , wherein x is in the range of greater than or equal to 0.3 to less than or equal to 0.45 and y in the range of greater than or equal to 0.2 to less than or equal to 0.35.

17 . The electrode as recited in claim 13 , wherein at least one of: a plurality of particles and the base body also includes at least one second lithiatable active material, which is doped with at least one redox-active doping element.

18 . The electrode as recited in claim 17 , wherein the at least one second lithiatable active material is doped with the redox-active element from the functional layer.

19 . The electrode as recited in claim 18 , wherein the second lithiatable active material is based on a doped manganese oxide.

20 . The electrode as recited in claim 19 , wherein the second lithiatable active material is based on the general chemical formula Li 2 Mn 1-2 M 2 O 3 , with z being in the range of greater than 0 to less than 1 and M is the redox-active element.

21 . The electrode as recited in claim 20 , wherein z is in the range of greater than or equal to 0.01 to less than or equal to 0.3.

22 . The electrode as recited in claim 21 , wherein z is in the range of greater than or equal to 0.01 to less than or equal to 0.2.

23 . The electrode as recited in claim 17 , wherein the base body includes a gradient of the redox-active doping element pointing in its thickness direction.

24 . The electrode as recited in claim 13 , wherein the redox-active element includes at least one ion radius, which is in the range of greater than or equal to 50 pm to less than or equal to 80 pm.

25 . The electrode as recited in claim 24 , wherein the at least one ion radius is in the range of greater than or equal to 60 pm to less than or equal to 70 pm.

26 . The electrode as recited in claim 25 , wherein the at least one ion radius is in the range of greater than or equal to 65 pm to less than or equal to 69 pm.

27 . The electrode as recited in claim 13 , wherein the redox-active element exhibits a minimal change in the ion radius during at least two successive oxidation stages.

28 . The electrode as recited in claim 27 , wherein the radius is in each case in the range of greater than or equal to 50 pm to less than or equal to 80 pm.

29 . The electrode as recited in claim 28 , wherein the radius is in each case in the range of greater than or equal to 59 pm to less than or equal to 70 pm.

30 . The electrode as recited in claim 13 , wherein the redox-active element is also a transition metal.

31 . The electrode as recited in claim 13 , wherein the at least one redox-active element is one of: niobium, niobium (IV), tungsten, tungsten (IV), molybdenum, or molybdenum (IV).

32 . An energy store for a lithium cell, including an electrode, the electrode comprising particles having a first lithiatable active material, which is based on a transition metal oxide, wherein at least one of the particles and a base body including the particles is provided at least partly with a functional layer which is lithium ion-conductive and includes at least one redox-active element.

33 . A method for manufacturing an electrode for an electrochemical energy store, comprising:
providing particles having at least one first lithiatable active material, which is based on a transition metal oxide; coating the particles with a functional layer, which is lithium ion-conductive and includes a redox-active element; adding a conductive additive and a binder; and one of: i) dry pressing components from a group made up of the particle having the functional layer, the conductive additive and the binder, or ii) dispersing the components from the group made up of the particles having the functional layer, the conductive additive and the binder in a solvent, the solvent being N-methyl-2-pyrrolidone; and applying a knife coating, the dispersion thus obtained on an aluminum foil.

34 . The method as recited in claim 33 , further comprising:
drying the dispersion.

35 . A method for manufacturing an electrode for an electrochemical energy store, comprising:
providing particles having at least one first lithiatable active material, which is based on a transition metal oxide; adding a conductive additive and a binder; dry pressing components from the group made up of the particles, the conductive additive and the binder, or dispersing the components from the group made up of the particles, the conductive additive and the binder in a solvent of N-methyl-2-pyrrolidone; applying a knife coating, the dispersion thus obtained on a metal carrier on an aluminum foil to form a base body including the particles; and coating the base body with a functional layer, which is lithium ion-conductive and includes a redox-active element.

36 . The method as recited in claim 35 , further comprising:
drying the dispersion.

Assignees

• Bosch Gmbh Robert

Inventors

• Marusczyk Anika
• Schumann Bernd
• Kerkamm Ingo
• Rolff Malte
• Eckl Thomas

Classifications

• H01M4/364

  as mixtures · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• H01M4/485

  of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy (H01M4/505, H01M4/525 take precedence) · CPC title

• H01M4/1391

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

• H01M4/043

  involving compressing or compaction · CPC title