Anode active material for lithium secondary battery and lithium secondary battery having the same

Patent metadata

Field	Value
Publication number	US-9502713-B2
Application number	US-201213537367-A
Country	US
Kind code	B2
Filing date	Jun 29, 2012
Priority date	Jun 10, 2010
Publication date	Nov 22, 2016
Grant date	Nov 22, 2016

Abstract

An anode active material for a lithium secondary battery and a lithium secondary battery having the same are disclosed. The anode active material for a lithium secondary battery includes a silicon alloy consisting of silicon and at least two kinds of metals other than silicon, each having the heat of mixing with the silicon of −23 kJ/mol or less. The anode active material for a lithium secondary battery has a high capacity, and thus, is useful in fabricating a high-capacity lithium secondary battery. Also, the anode active material for a lithium secondary battery has a small crystal size of a silicon phase and consequently a small change in volume during charging/discharging, and thus, ensures excellent cycle life characteristics in applications to batteries.

First claim

What is claimed is:

1. An anode active material for a lithium secondary battery, consisting of:
a silicon alloy in powder form including:
silicon; and
two kinds of metals other than the silicon, each having the heat of mixing with the silicon of −23 kJ/mol or less,

wherein:
(a) the heat of mixing represents heat generated or absorbed when mixing the silicon and the two kinds of metals other than the silicon in a molten state, and the heat of mixing having a minus value represents that the mixing reaction between the silicon and the at least two kinds of metals other than the silicon in a molten state is an exothermic reaction;
(b) the silicon alloy is represented by the following Chemical Formula 1:
Si x A y B z   Chemical Formula 1

 wherein A is Ce or La, B is Ni or Ti;
and each of x, y, and z indicates atomic %, x+y+z=100, 70≦x, 0<y≦15, 0<z≦20;
(c) the silicon phase of the silicon alloy has a crystal size of 5 nm to 20 nm; and
(d) the silicon alloy has an average particle size of 0.5 μm (micrometer) to 50 μm.

2. An anode of a lithium secondary battery, comprising:
a current collector; and
an anode active material layer formed on at least one surface of the current collector, comprising the anode active material defined in claim 1 and a binder.

3. A lithium secondary battery, comprising:
a cathode;
the anode as defined in claim 2 ; and
a separator interposed between the cathode and the anode.

Assignees

• Jung Dong-Sub
• Kim Ki-Tae
• Kim Je-Young
• Ji Hye-Min
• Lg Chemical Ltd

Inventors

• Jung Dong-Sub
• Kim Ki-Tae
• Kim Je-Young
• Ji Hye-Min

Classifications

• H01M10/052

  Li-accumulators · CPC title

• H01M4/134 Primary

  Electrodes based on metals, Si or alloys · CPC title

• C22C28/00

  Alloys based on a metal not provided for in groups C22C5/00 - C22C27/00 · CPC title

• H01M4/38 Primary

  of elements or alloys · CPC title

• Y02E60/122

  Cross-Sectional Technologies · mapped topic