Alkaline cell with improved reliability and discharge performance

Patent metadata

Field	Value
Publication number	US-10446832-B2
Application number	US-201615543928-A
Country	US
Kind code	B2
Filing date	Jan 11, 2016
Priority date	Jan 16, 2015
Publication date	Oct 15, 2019
Grant date	Oct 15, 2019

Abstract

A negative electrode for an alkaline battery cell which includes zinc-based particles, wherein less than 20% of the zinc-based particles, by weight relative to the total zinc in the electrode, have a particle size of greater than about 150 micrometers, is provided. An alkaline electrochemical cell that includes the negative electrode and a method for reducing the gassing of the electrochemical cell is also provided.

First claim

What is claimed is:

1. A gelled anode for an alkaline battery cell comprising, the gelled anode comprising:
a gelling agent;
an alkaline electrolyte comprising a hydroxide material;
a surfactant; and
zinc-based particles, wherein less than 20% of the zinc-based particles, by weight relative to the total zinc in the electrode, have a particle size of greater than about 150 micrometers;
wherein the zinc-based particles have an aspect ratio of from about 1.85 to about 4.15 and an apparent density of about 2.40 g/cm 3 to about 3.15 g/cm 3 .

2. The gelled anode of claim 1 , wherein about 10% to about 20% of the zinc-based particles, by weight relative to the total zinc in the electrode, have a particle size of greater than about 150 micrometers.

3. The gelled anode of claim 1 , wherein the zinc-based particles have a roundness of at least 1.5.

4. The gelled anode of claim 1 , wherein the zinc-based particles are zinc alloy particles having an average particle size of about 100 micrometers to about 130 micrometers.

5. The gelled anode of claim 1 , wherein about 20% to about 70% of the zinc-based particles, by weight relative to the total zinc in the electrode, have a particle size of less than about 75 micrometers.

6. The gelled anode of claim 5 , wherein about 20% to about 45% by weight relative to the total zinc in the electrode have a particle size of less than about 75 micrometers, about 1% to about 10% by weight relative to the total zinc in the electrode have a particle size of less than about 45 micrometers, and about 10% to about 20% by weight relative to the total zinc in the electrode, have a particle size of greater than about 150 micrometers.

7. The gelled anode of claim 1 , wherein the hydroxide is potassium hydroxide.

8. The gelled anode of claim 1 , wherein the surfactant is an organic phosphate ester surfactant, a polyethylene glycol ether, an ethoxylated alkylphenol, a tallow amine, diethylenetriamine, an amphoteric surfactant, a sulfonated organic acid surfactant, a sulfated organic acid surfactant, hexyl diphenyl oxide sulfonic acid, Rhodafac RM-510, Rhodafac RA-600, Rhodafac RS-610, Witconate 1840X, Mafo 13 MOD1, or a combination of any two or more thereof.

9. The gelled anode of claim 1 , wherein the surfactant is present at a concentration ranging from between 0.0010% and 0.040% relative to the weight of the gelled anode.

10. The gelled anode of claim 1 , having a yield stress value of about 600 to about 3500.

11. The gelled anode of claim 1 , having a viscosity of about 25000 cps to about 150000 cps.

12. An alkaline electrochemical cell comprising:
a positive current collector;
a cathode in contact with the positive current collector;
a negative current collector;
a gelled anode according to claim 1 in contact with the negative current collector
and

a separator between the cathode and the anode.

13. A method for reducing the gassing of an electrochemical cell subject to gassing, the method comprising:
providing as the active anode of said cell, a gelled anode comprising:
a gelling agent;
an alkaline electrolyte comprising a hydroxide material;
a surfactant; and
zinc-based particles;
wherein:
less than 20% of the zinc-based particles, by weight relative to the total zinc in the electrode, have a particle size of greater than about 150 micrometers, and less than 10% of the zinc-based particles, by weight relative to the total zinc in the electrode, have a particle size of less than about 45 micrometers; and
the zinc-based particles have an aspect ratio of from about 1.85 to about 4.15 and
an apparent density of about 2.40 g/cm 3 to about 3.15 g/cm 3 .

14. The method of claim 13 , wherein the gassing is reduced by about 10% to 50% in battery cells having zinc powders containing less than 20% of coarse particles relative to cells having an active anode comprising zinc-based particles at apparent densities between 2.50 and 3.0 g/ml and coarse content ( >150 micrometers) between 20% to 60% by weight relative to the total zinc electrode.

Assignees

• Spectrum Brands Inc
• Energizer Brands Llc

Inventors

• Armacanqui M Edgar
• Li Wen
• Hadley John
• Hennek Matthew

Classifications

• H01M6/5072

  Preserving or storing cells · CPC title

• H01M6/04

  Cells with aqueous electrolyte · CPC title

• H01M4/12

  of consumable metal or alloy electrodes (use of alloy compositions as active materials H01M4/38) · CPC title

• H01M4/62

  Selection of inactive substances as ingredients for active masses, e.g. binders, fillers · CPC title

• H01M4/42

  Alloys based on zinc · CPC title