← Back to Patent Explorer
US5344728A Expired / Lapsed US ⏱️ 0.0 years remaining

Compositionally and structurally disordered multiphase nickel hydroxide positive electrode for alkaline rechargeable electrochemical cells

Assignee: Chevron Technology Ventures LLC
•
Filing: 1992-11-12
•
Granted: 1994-09-06
•
Expires: 2012-11-12
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A positive electrode for use in alkaline rechargeable electrochemical cells comprising: a material comprising a compositionally and structurally disordered multiphase nickel hydroxide host matrix which includes at least one modifier chosen from the group consisting of F, Li, Na, K, Mg, Ba, Ln, Se, Nd, Pr, Y, Co, Zn, Al, Cr, Mn, Fe, Cu, Zn, Sc, Sn, Sb, Te, Bi, Ru, and Pb. A process for forming a high loading uniformly distributed multiphase substantially nitrate free sintered positive electrode for use in an alkaline rechargeable electrochemical cell, the process comprising: (1) fabricating sintered electrode material by forming a slurry of nickel powder, water, carboxy methyl cellulose binder, methyl cellulose binder, and a poly(ethylene oxide) polymer; spreading the slurry on a preoxidized perforated nickel substrate; drying the slurry; and sintering the slurry; (2) impregnating the sintered electrode material using multiple impregnation cycles to attain high loading, where each impregnation cycle comprises the steps of: placing the sintered electrode material on a rack; dipping the rack into nickel nitrate; allowing the rack to drip dry; dipping the dried rack into NaOH solution; spraying the rack in a first tank with deionized water overflowing from a second tank; dipping the rack in the second tank filled with deionized water overflowing from a third tank; dipping the rack in the third tank filling with deionized water at a rate of 8-10 gpm; drying the rack; and flipping the rack to attain uniform deposition of material; where in the median dip cycle and in the final dip cycle of the multiple impregnation cycles, the step of dipping the rack into nickel nitrate is replaced by a step of dipping the rack into cobalt nitrate to produce an enriched cobalt surface; and (3) forming the impregnated sinter into positive electrode material by presoaking the impregnated sinter in NaOH presoak tanks to substantially eliminate nitrates; brushing the presoaked impregnated sinter in a surface brushing station; charging the brushed impregnated sinter; discharging the charged impregnated sinter; rinsing the discharged impregnated sinter; and drying the rinsed impregnated sinter to complete the formation of positive electrode material.

Inventors

  • 👤 Stanford R. Ovshinsky
  • 👤 Michael A. Fetcenko
  • 👤 Srinivasan Venkatesan
  • 👤 Arthur Holland

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 17:55
CPC Classifications
H; H01; H01M; H01M10/00; H01M10/34; H01M10/345; H01M4/00; H01M4/02; H01M4/24; H01M4/32; H01M4/04; H01M4/26; H01M4/28; H01M4/36; H01M4/48; H01M4/52; H01M4/64; H01M4/70; H01M4/80; Y; Y02; Y02E; Y02E60/00; Y02E60/10

Claims Analysis

Total Claims: 41
Claim 1
Independent Claim 34 words
A sealed nickel metal hydride cell comprising a sintered nickel hydroxide electrode lacking cadmium wherein said sealed nickel metal hydride cell has an energy density ≧560 mAh/cc, and a cycle life of ≧500 cycles.
Claim 2
Dependent Claim 34 words
A sealed nickel metal hydride cell comprising a sintered nickel hydroxide electrode lacking cadmium wherein said sealed nickel metal hydride cell has an energy density ≧560 mAh/cc, and a cycle life of ≧500 cycles.
Claim 3
Dependent Claim 29 words
The sealed nickel metal hydride cell claimed in claim 1, wherein said sealed nickel metal hydride cell has a self discharge of <30% in 30 days at 20° C.
Claim 4
Dependent Claim 22 words
The sealed nickel metal hydride cell claimed in claim 1, wherein residual nitrates are present in an amount less than 200 ppm.
Claim 5
Dependent Claim 24 words
The sealed nickel metal hydride cell claimed in claim 1, wherein said sealed nickel metal hydride cell has an energy density of ≧600 mAh/cc.
Claim 6
Dependent Claim 23 words
The sealed nickel metal hydride cell claimed in claim 1, wherein said sintered nickel hydroxide electrode has pores approximately 30 microns in size.
Claim 7
Dependent Claim 24 words
The sealed nickel metal hydride cell claimed in claim 1, wherein said sintered nickel hydroxide electrode contains greater than 6 wt % coprecipitated cobalt.
Claim 8
Dependent Claim 22 words
The sealed nickel metal hydride cell claimed in claim 1, wherein said sintered nickel hydroxide electrode contains 9-10 wt % coprecipitated cobalt.
Claim 9
Dependent Claim 23 words
The sealed nickel metal hydride cell claimed in claim 3, wherein the overall porosity of said sintered nickel hydroxide electrode is around 80%.
Claim 10
Dependent Claim 68 words
The sealed nickel metal hydride cell claimed in claim 1, wherein said sintered nickel hydroxide electrode is a compositionally and structurally disordered multiphase material comprising a nickel hydroxide host matrix and at least one modifier chosen from the group consisting of F, Li, Na, K, Mg, Ba, Ln, Se, Nd, Pr, Y, Co, Zn, Al, Cr, Mn, Fe, Cu, Zn, Sc, Sn, Sb, Te, Bi, Ru, and Pb.
Claim 11
Dependent Claim 49 words
The sealed nickel metal hydride cell as claimed in claim 9, comprising: at least three modifiers chosen from the group consisting of F, Li, Na, K, Mg, Ba, Ln, Se, Nd, Pr, Y, Co, Zn, Al, Cr, Mn, Fe, Cu, Zn, Sc, Sn, Sb, Te, Bi, Ru, and Pb.
Claim 12
Dependent Claim 50 words
A sealed nickel metal hydride cell comprising: a positive electrode lacking cadmium and having residual nitrates present in an amount less than 200 ppm, wherein said sealed nickel metal hydride cell has an energy density of ≧560 mAh/cc and a self discharge of ≦30% in 30 days at 20° C.
Claim 13
Dependent Claim 50 words
A sealed nickel metal hydride cell comprising: a positive electrode lacking cadmium and having residual nitrates present in an amount less than 200 ppm, wherein said sealed nickel metal hydride cell has an energy density of ≧560 mAh/cc and a self discharge of ≦30% in 30 days at 20° C.
Claim 14
Dependent Claim 24 words
The sealed nickel metal hydride cell claimed in claim 11, wherein said sealed nickel metal hydride cell has an energy density of ≦600 mAh/cc.
Claim 15
Dependent Claim 24 words
The sealed nickel metal hydride cell claimed in claim 11, wherein said sealed nickel metal hydride cell has a cycle life of ≧500 cycles.
Claim 16
Dependent Claim 16 words
The sealed nickel metal hydride cell claimed in claim 11, wherein said positive electrode is sintered.
Claim 17
Dependent Claim 25 words
The sealed nickel metal hydride cell claimed in claim 11, wherein said positive electrode comprises sintered electrode material having pores approximately 30 microns in size.
Claim 18
Dependent Claim 20 words
The sealed nickel metal hydride cell claimed in claim 11, wherein said negative electrode is a V-Ti-Zr-Ni type negative electrode.
Claim 19
Dependent Claim 22 words
The sealed nickel metal hydride cell claimed in claim 11, wherein said positive electrode contains greater than 6 wt % coprecipitated cobalt.
Claim 20
Dependent Claim 20 words
The sealed nickel metal hydride cell claimed in claim 11, wherein said positive electrode contains 9-10 wt % coprecipitated cobalt.
Claim 21
Dependent Claim 27 words
The sealed nickel metal hydride cell claimed in claim 18, wherein the concentration of surface enriched cobalt on said positive electrode is greater than 10 wt %.
Claim 22
Dependent Claim 20 words
The sealed nickel metal hydride cell claimed in claim 14, wherein overall porosity of said positive electrode is around 80%.
Claim 23
Dependent Claim 64 words
The sealed nickel metal hydride cell claimed in claim 11, wherein said positive electrode comprises a compositionally and structurally disordered multiphase nickel hydroxide host matrix which includes at least three modifiers chosen from the group consisting of F, Li, Na, K, Mg, Ba, Ln, Se, Nd, Pr, Y, Co, Zn, Al, Cr, Mn, Fe, Cu, Zn, Sc, Sn, Sb, Te, Bi, Ru, and Pb.
Claim 24
Dependent Claim 49 words
The sealed nickel metal hydride cell as claimed in claim 18, comprising: at least three modifiers chosen from the group consisting of F, Li, Na, K, Mg, Ba, Ln, Se, Nd, Pr, Y, CO, Zn, Al, Cr, Mn, Fe, Cu, Zn, Sc, Sn, Sb, Te, Bi, Ru, and Pb.
Claim 25
Dependent Claim 54 words
A sealed nickel metal hydride cell comprising: a positive electrode; that is sintered and lacks cadmium, and a V-Ti-Zr-Ni metal hydride negative electrode; wherein said sealed nickel metal hydride cell has an energy density of ≧560 mAh/cc, a cycle life of ≧500 cycles, and self discharge of ≦30% in 30 days at 20° C.
Claim 26
Dependent Claim 54 words
A sealed nickel metal hydride cell comprising: a positive electrode; that is sintered and lacks cadmium, and a V-Ti-Zr-Ni metal hydride negative electrode; wherein said sealed nickel metal hydride cell has an energy density of ≧560 mAh/cc, a cycle life of ≧500 cycles, and self discharge of ≦30% in 30 days at 20° C.
Claim 27
Dependent Claim 26 words
The sealed nickel metal hydride cell claimed in claim 23, wherein residual nitrates are present in said positive electrode in an amount less than 200 ppm.
Claim 28
Dependent Claim 24 words
The sealed nickel metal hydride cell claimed in claim 24, wherein said sealed nickel metal hydride cell has an energy density of ≧600 mAh/cc.
Claim 29
Dependent Claim 21 words
The sealed nickel metal hydride cell claimed in claim 23, wherein said positive electrode has pores approximately 30 microns in size.
Claim 30
Dependent Claim 22 words
The sealed nickel metal hydride cell claimed in claim 23, wherein said positive electrode contains greater than 6 wt % coprecipitated cobalt.
Claim 31
Dependent Claim 20 words
The sealed nickel metal hydride cell claimed in claim 23, wherein said positive electrode contains 9-10 wt % coprecipitated cobalt.
Claim 32
Dependent Claim 22 words
The sealed nickel metal hydride cell claimed in claim 27, wherein the overall porosity of said positive electrode material is around 80%.
Claim 33
Dependent Claim 63 words
The sealed nickel metal hydride cell claimed in claim 27, wherein said positive electrode comprises a compositionally and structurally disordered multiphase nickel hydroxide host matrix and at least one modifier chosen from the group consisting of F, Li, Na, K, Mg, Ba, Ln, Se, Nd, Pr, Y, Co, Zn, Al, Cr, Mn, Fe, Cu, Zn, Sc, Sn, Sb, Te, Bi, Ru, and Pb.
Claim 34
Dependent Claim 93 words
A sealed nickel metal hydride cell comprising a sintered positive electrode wherein said positive electrode comprises: a nickel substrate that is preoxidized and perforated; a nickel sinter having pores and an outer surface on said nickel substrate; and nickel hydroxide and cobalt hydroxide precipitate in said pores and on said outer surface; where said sintered positive electrode contains <200 ppm residual nitrates and lacks Cd, and said sealed nickel metal hydride cell has an energy density of ≧560 Ah/cc and a self discharge of ≦30% in 30% in 30 days at 20° C.
Claim 35
Dependent Claim 93 words
A sealed nickel metal hydride cell comprising a sintered positive electrode wherein said positive electrode comprises: a nickel substrate that is preoxidized and perforated; a nickel sinter having pores and an outer surface on said nickel substrate; and nickel hydroxide and cobalt hydroxide precipitate in said pores and on said outer surface; where said sintered positive electrode contains <200 ppm residual nitrates and lacks Cd, and said sealed nickel metal hydride cell has an energy density of ≧560 Ah/cc and a self discharge of ≦30% in 30% in 30 days at 20° C.
Claim 36
Dependent Claim 21 words
The sealed nickel metal hydride cell claimed in claim 31, wherein said positive electrode has pores approximately 30 microns in size.
Claim 37
Dependent Claim 21 words
The sealed nickel metal hydride cell claimed in claim 31, wherein said positive electrode contains greater than 6 wt % cobalt.
Claim 38
Dependent Claim 20 words
The sealed nickel metal hydride cell claimed in claim 31, wherein said positive electrode contains 9-10 wt % coprecipitated cobalt.
Claim 39
Dependent Claim 31 words
The sealed nickel metal hydride cell claimed in claim 31, wherein the concentration of cobalt on said outer surface is greater than the internal concentration of cobalt in said nickel sinter.
Claim 40
Dependent Claim 25 words
The sealed nickel metal hydride cell claimed in claim 31, wherein the concentration of cobalt on said outer surface is greater than 10 wt %.
Claim 41
Dependent Claim 22 words
The sealed nickel metal hydride cell claimed in claim 32, wherein the overall porosity of said sintered electrode material is around 80%.

References Cited (Backward Citations)

US4064332A Cited
US4623597A Cited
US4551400A Cited
US4696875A Cited
US4728586A Cited
US4844948A Cited
US4985318A Cited
US4975035A Cited
US5096667A Cited
US5132177A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-09-05 1998-03-07 1998-09-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-09-05 2002-03-07 2002-09-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-09-05 2006-03-07 2006-09-06 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag