Degradation mechanisms of nylon separator materials for a nickel-cadmium cell in KOH electrolytes

Journal Article · Wed Mar 01 04:00:00 EST 1989 · J. Electrochem. Soc.; (United States)

DOI:https://doi.org/10.1149/1.2096696· OSTI ID:5861861

Lim, H S; Margerum, J D; Verzwyvelt, S A; Lackner, A M; Knechtli, R C

Degradation reactions of a nylon 6 battery separator material have been studied in 4-34% aqueous KOH electrolytes at 35/sup 0/-110/sup 0/C. In a Ni/Cd cell, this degradation involves a slow hydrolysis reaction followed by fast electrochemical oxidations of the hydrolysis reaction products. Arrhenius activation energy of the hydrolysis reaction in 34% KOH was 20.0 +- 0.3 kcal/mole. A plot of the hydrolysis rate at 100/sup 0/C vs. hydroxyl ion concentration gave a rate maximum at about 16% KOH, and the mechanism for this effect is discussed. Electrochemical oxidations of the hydrolysis product, 6-aminocaproate ion, appear to proceed rapidly in several sequential steps at a nickel oxide electrode. In a Ni/Cd cell, the combination of nylon separator hydrolysis followed by electrochemical oxidation of the products can seriously degrade the battery lifetime. The rate of the hydrolysis of nylon 66 separator material was approximately one half of that of the nylon 6 material.

• Research Organization: Hughes Research Labs., Malibu, CA (USA)
• OSTI ID: 5861861
• Journal Information: J. Electrochem. Soc.; (United States), Journal Name: J. Electrochem. Soc.; (United States) Vol. 136:3; ISSN JESOA
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
250902 -- Energy Storage-- Batteries-- Performance & Testing
250903* -- Energy Storage-- Batteries-- Materials
Components
& Auxiliaries
36 MATERIALS SCIENCE
360105 -- Metals & Alloys-- Corrosion & Erosion
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400400 -- Electrochemistry
ACTIVATION ENERGY
ALKALI METAL COMPOUNDS
BATTERY SEPARATORS
CHALCOGENIDES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CHEMISTRY
ELECTRIC BATTERIES
ELECTROCHEMICAL CELLS
ELECTROCHEMISTRY
ELECTRODES
ELECTROLYTES
ENERGY
HYDROGEN COMPOUNDS
HYDROXIDES
KINETICS
MATERIALS
METAL-METAL OXIDE BATTERIES
NICKEL COMPOUNDS
NICKEL OXIDES
NICKEL-CADMIUM BATTERIES
NYLON
ORGANIC COMPOUNDS
ORGANIC POLYMERS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PETROCHEMICALS
PETROLEUM PRODUCTS
PLASTICS
POLYAMIDES
POLYMERS
POTASSIUM COMPOUNDS
POTASSIUM HYDROXIDES
REACTION KINETICS
SERVICE LIFE
SYNTHETIC MATERIALS
TRANSITION ELEMENT COMPOUNDS