Nickel-iron battery with high cycle life

Patent metadata

Field	Value
Publication number	US-2016036094-A1
Application number	US-201514882733-A
Country	US
Kind code	A1
Filing date	Oct 14, 2015
Priority date	Feb 6, 2013
Publication date	Feb 4, 2016
Grant date	—

Abstract

The present invention provides one with a high cycle life Ni—Fe battery. The battery uses a particular electrolyte. The resulting characteristics of cycle life, as well as power and charge retention, are much improved over conventional Ni—Fe batteries.

First claim

What is claimed is:

1 . A battery, comprising:
a nickel cathode; an iron anode comprising an iron active material that is metal iron or an iron oxide material and a binder; and an electrolyte comprising 6 to 7.5 M sodium hydroxide, 0.5 to 2.0 M lithium hydroxide, and 1-2 wt % sodium sulfide based on the weight of the electrolyte, with the battery exhibiting a cycle life of at least about 10,000 cycles.

2 . The battery of claim 1 , further comprising a polyolefin battery separator.

3 . The battery of claim 1 , which is a sealed battery.

4 . The battery of claim 1 , wherein the iron anode is comprised of a single layer of a conductive substrate coated on at least one side with a coating comprising the iron active material and the binder.

5 . The battery of claim 4 , wherein the substrate is coated on both sides.

6 . The battery of claim 1 , further exhibiting a specific energy of at least about 105 watt hours/kg.

7 . The battery of claim 1 , further exhibiting an energy density of at least about 183 watt hours/liter.

8 . The battery of claim 1 , further exhibiting a specific power of at least about 2100 watts/kg.

9 . The battery of claim 1 , further exhibiting a power density of at least about 3660 watts/liter.

10 . The battery of claim 1 , further exhibiting a watt hour efficiency of at least about 95%.

11 . The battery of claim 1 , further exhibiting a charge retention, measured as capacity at 28 days 20° C., of at least about 95%.

12 . The battery of claim 1 , exhibiting
a specific energy of at least about 105 watt hours/kg; an energy density of at least about 183 watt hours/liter; a watt hour efficiency of at least about 95%; and a charge retention of at least about 95%.

13 . The battery of claim 1 , wherein the binder is a polyvinyl alcohol binder.

14 . A battery, comprising:
a nickel cathode; an iron anode comprising an iron active material that is metal iron or an iron oxide material and a binder; and an electrolyte comprising sodium hydroxide, lithium hydroxide, and a concentration of 0.23 wt % to 0.75 wt % sulfide based on the weight of the electrolyte, with the battery exhibiting a cycle life of at least about 10,000 cycles.

15 . The battery of claim 14 , wherein electrolyte comprises sodium sulfide.

16 . The battery of claim 14 , wherein the binder is a polyvinyl alcohol binder.

Assignees

• Encell Technology Inc

Inventors

• Ogg Randy

Classifications

• H01M10/30

  Nickel accumulators (H01M10/34 takes precedence) · CPC title

• H01M2300/0014

  Alkaline electrolytes · CPC title

• H01M4/24

  Electrodes for alkaline accumulators · CPC title

• H01M4/248

  Iron electrodes · CPC title

• H01M10/26 Primary

  Selection of materials as electrolytes · CPC title