Nanoporous tin powder for energy applications

Patent metadata

Field	Value
Publication number	US-2017110717-A1
Application number	US-201615295884-A
Country	US
Kind code	A1
Filing date	Oct 17, 2016
Priority date	Oct 15, 2015
Publication date	Apr 20, 2017
Grant date	—

Abstract

A nanoporous tin is disclose, along with a method of fabrication thereof, the tin having a hierarchical nanoporous and mesoporous ligament morphology that exhibits long-term cyclability, particularly when used as anode material in Li-ion. One embodiment of the present technology is a fabrication method to directly produce nanoporous tin in powder form, rather than a monolithic piece of nanoporous metal, so that the NP-Sn powder can be directly integrated into composite electrodes using commercial battery electrode processing techniques.

First claim

What is claimed is:

1 . An active material for use in an energy storage device, comprising:
a population of micrometer sized metal, semi metal or semiconducting particles; wherein the each of the particles comprise a hierarchically porous structure comprising a network of interconnected ligament-shaped structures and pores; said pores being defined by adjacent interconnected ligament-shaped structures; wherein each of said interconnected ligament-shaped structures comprises a granular structure comprising a population of sub-pores; and wherein said hierarchically porous structure is configured to allow for cycling induced volume expansion upon being electrochemically alloyed within the energy storage device.

2 . The material of claim 1 , wherein said pores comprise nanopores and wherein said sub-pores comprise mesopores.

3 . The material of claim 2 , wherein the mesopores comprise pores approximately 5 nm in size.

4 . The material of claim 2 , wherein said particles are composed of a metal or semiconductor selected from the group of metals and semiconductors consisting essentially of Ge, Sb, As, Bi, Si, Sn, SnC, SnSb, SnSi, SnGe, SnAs, SnAl, SnBi, SnCo, SnNi, and SnPb.

5 . The material of claim 2 , wherein said particles comprise nanoporous tin.

6 . The material of claim 2 , wherein said particles have a diameter between approximately 1-100 μm.

7 . The material of claim 2 , wherein the material is configured to be coupled to a charge collector as an electrode.

8 . The material of claim 7 , wherein the material is configured to allow for cycling induced volume expansion upon being electrochemically alloyed with LI Na or Mg.

9 . An electrode for use with an energy storage device, comprising:
(a) a macroporous conductor; (b) an active material configured to be disposed within macropores of the macroporous conductor, the active material comprising:
(i) a population of micrometer sized metal, semi metal or semiconducting particles;
(ii) wherein the each of the particles comprise a hierarchically porous structure comprising a network of interconnected ligament-shaped structures and pores;
(iii) said pores being defined by adjacent interconnected ligament-shaped structures;
(iv) wherein each of said interconnected ligament-shaped structures comprises a granular structure comprising a population of sub-pores; and
(c) a charge collector electrically coupled with the active material; (d) wherein said hierarchically porous structure is configured to allow for cycling induced volume expansion upon being electrochemically alloyed within the energy storage device.

10 . The electrode of claim 9 :
wherein said pores comprise nanopores; and wherein said sub-pores comprise mesopores.

11 . The electrode of claim 10 , wherein the mesopores comprise pores approximately 5 nm in size.

12 . The electrode of claim 10 , wherein said particles are composed of a metal or semiconductor selected from the group of metals and semiconductors consisting essentially of Ge, Sb, As, Bi, Si, Sn, SnC, SnSb, SnSi, SnGe, SnAs, SnAl, SnBi, SnCo, SnNi, and SnPb.

13 . The electrode of claim 10 , wherein said particles comprise nanoporous tin.

14 . The electrode of claim 10 , wherein said particles have a diameter between approximately 1-100 μm.

15 . The electrode of claim 10 , wherein the material is configured to allow for cycling induced volume expansion upon being electrochemically alloyed with LI Na or Mg.

16 . The electrode of claim 10 , wherein said macroporous conductor comprises an additive selected from the group of additives consisting essentially of: vapor grown carbon fibers (VGCF), graphite, carbon nanotubes, fullerenes, graphene flakes, carbon black, and conductive polymer nanoparticles.

17 . The electrode of claim 10 , further comprising:
a binder; wherein said binder comprises a carboxymethyl cellulose (CMC) or, polyacrylic acid or, styrene-butadiene rubber or, polyvinylidene fluoride binder and combinations thereof.

18 . A method of fabricating an active material for use in an energy storage device:
(a) providing an alloy of Ge, Si, Sb, As, Bi or Sn with a sacrificial metal in a ratio of approximately 55 to 99 sacrificial metal atoms to every 100 atoms of alloy; and (b) sacrificing said sacrificial metal atoms of the alloy to produce porous particles of a metal (Ge, Si, Sb, As, Bi, Sn, SnC, SnSb, SnSi, SnGe, SnAs, SnAl, SnBi, SnCo, SnNi, and SnPb); (c) sacrificing the sacrificial metal atoms is performs such that the particles of metal are pulverized into a population of micrometer sized particles; and (d) wherein the each of the particles comprise a hierarchically porous structure comprising a network of interconnected ligament-shaped structures and pores.

19 . The method of claim 18 :
said pores being defined by adjacent interconnected ligament-shaped structures; wherein each of said interconnected ligament-shaped structures comprises a granular structure comprising a population of sub-pores.

20 . The method of claim 19 , wherein said hierarchically porous structure is configured to allow for cycling induced volume expansion upon being electrochemically alloyed within the energy storage device.

21 . The method of claim 18 , wherein said alloy is selected from the group of alloys consisting essentially of AX, where A=Ge, Si, Sb, As, Bi or Sn, and X═Mg, Mn, Zn, or Al and wherein said alloys generate Ge, Si, Sb, As, Bi, and Sn.

22 . The method of claim 18 , wherein said alloy is selected from the group of alloys consisting essentially of SnCX, SnSbX, SnSiX, SnGeX, SnAsX, SnAlX, SnBiX, SnCoX, SnNiX, and SnPbX where X═Mg or Al or Mn or Zn, and wherein said alloys generate SnC, SnSb, SnSi, SnGe, SnAs, SnAl, SnBi, SnCo, SnNi, and SnPb.

23 . The method of claim 18 , wherein said alloy comprises SnMg.

24 . The method of claim 21 , wherein sacrificing the sacrificial metal atoms comprises dealloying the SnMg to substantially remove Mg from the alloy to generate a nanoporous tin powder.

25 . The method of claim 21 :
wherein sacrificing the sacrificial metal atoms comprises dealloying the alloy with a corroding solution; and wherein the corroding solution is selected so as to have a substantially uniform rate of reaction with the alloy.

26 . The method of claim 25 , wherein the corroding solution comprises one or more of: ammonium sulfate, potassium hydroxide, sodium hydroxide, hydrochloric acid, sulfuric acid, or acetic acid.

27 . The method of claim 24 , wherein the SnMg is dealloyed with ammonium sulfate.

28 . The method of claim 27 , wherein the SnMg is dealloyed according to the equation:
Mg(s)+2NH 4 + (aq)→Mg 2+ +H 2 (g)+2NH 3 (g).

Assignees

• Univ California

Inventors

• Tolbert Sarah
• Detsi Eric
• Cook John

Classifications

• H01M4/387

  Tin or alloys based on tin · CPC title

• H01M4/134 Primary

  Electrodes based on metals, Si or alloys · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/622

  being polymers · CPC title

• H01M4/625

  Carbon or graphite · CPC title