US 8,999,008 B2 · Method of forming an electrode assembly

Abstract

When electrode films are prepared for lithium electrochemical cells, problems are often encountered in laminating the films with an appropriate intervening electrolyte layer. This presents a significant challenge because proper alignment of the three layers and complete lamination at the interfaces are crucial to good cell performance. Often lamination is imperfect with gaps and defects at the interfaces. The disclosure herein describes a method of casting or extruding a polymer electrolyte directly onto an electrode film to create an electrode assembly with a continuous, defect-free interface. In some arrangements, there is some slight intermixing of the layers at the interface. A complete cell can be formed by laminating two such electrode assemblies to opposite sides of an additional electrolyte or to one another.

Claims32

Dependent claims

A method of forming an electrode assembly, comprising:

mixing together electrode active material and a liquefied first polymer electrolyte to make a slurry;
forming the slurry into a thin film;
allowing the first polymer electrolyte to solidify, thereby forming an electrode comprising a solid first polymer electrolyte binding together the first electrode active material;
preparing a liquefied second polymer electrolyte, the electrolyte adapted to wet the thin film electrode;
applying the liquefied second polymer electrolyte onto the thin film electrode to form a liquid layer;
and
allowing the liquid layer to solidify, thereby forming a solid second polymer electrolyte layer on the thin film electrode;
wherein no additional binder is used to form the electrode.

5 more elements

A method of making a battery cell, comprising the steps of:

a) mixing together first electrode active material and a liquefied first polymer electrolyte to make a slurry;
b) forming the slurry into a first thin film;
c) allowing the first polymer electrolyte to solidify, thereby forming a thin film electrode comprising a solid first polymer electrolyte binding together the first electrode active material;
d) preparing a liquefied second polymer electrolyte adapted to wet the first thin film electrode;
e) applying the liquefied second polymer electrolyte onto the first thin film electrode to form a liquefied second polymer electrolyte layer on the first thin film electrode;
f) allowing the liquefied second polymer electrolyte to solidify at least partially to form a first electrode assembly;
wherein no additional binder is used to form the first electrode assembly;
and
g) positioning a second electrode assembly to be in ionic communication with the second solid polymer electrolyte layer, thereby forming a battery cell.

6 more elements

A method of making a battery cell, comprising the steps of:

making a first electrode assembly, comprising the steps of:
a) mixing together first electrode active material and a liquefied first polymer electrolyte to make a slurry;
b) forming the slurry into a first thin film electrode;
c) preparing a liquefied second polymer electrolyte adapted to wet the first thin film electrode;
d) applying the liquefied second polymer electrolyte onto the first thin film electrode to form a liquefied second polymer electrolyte layer on the first thin film electrode;
and
e) allowing the liquefied second polymer electrolyte to solidify at least partially, thereby forming a first electrode assembly;
wherein no additional binder is used to form the first electrode assembly;
making a second electrode assembly, comprising the steps of:
f) mixing together second electrode active material and a liquefied third polymer electrolyte to make a slurry;
g) forming the slurry into a second thin film electrode;
h) preparing a liquefied fourth polymer electrolyte adapted to wet the second thin film electrode;
i) applying the liquefied fourth polymer electrolyte onto the second thin film electrode to form a liquefied fourth polymer electrolyte layer on the second thin film electrode;
and
j) allowing the liquefied fourth polymer electrolyte to solidify at least partially, thereby forming a second electrode assembly;
wherein no additional binder is to form the second electrode assembly;
and
positioning the fourth solid polymer electrolyte layer to be in ionic communication with the second solid polymer electrolyte layer.

15 more elements

Dependencies are inferred from the claim text.

Method of forming an electrode assembly

Life of this patent

Method of forming an electrode assembly

Life of this patent

Abstract

Claims32