A novel class of positive electrodes for rechargeable batteries

Technical Report · Thu Oct 01 04:00:00 EDT 1987

OSTI ID:5688117

Mailhe, C C

A novel class of organosulfur positive electrodes for intermediate temperature rechargeable batteries is described here. High temperature batteries such as sodium/sulfur exhibit alluring and unrivaled power and energy densities but unfortunately are plagued by corrosion problems. A decrease in the operating temperature from 350/sup 0/C to the 110 to 150/sup 0/C temperature range resulted in a simplified cell technology allowing for the use of polymeric seals. The non-aggressive nature of the positive electrode lessened also considerably the corrosion issues. A tetraethylthiuram disulfide/diethyldithiocarbamate cell was first investigated because of its attractive theoretical energy density of 360 Wh/kg and because of the low melting point of the diethyldithiocarbamate sodium salt (145/sup 0/C), condition necessary to maintain the electrode in the liquid state. (Sodium and Beta'' Alumina were respectively the negative electrode and the solid electrolyte). The low melting sodium salt requirement can be advantageously replaced by the use of a solvent in charge of solubilizing the sodium salt generated during discharged. Low viscosity and high dielectric constant were identified as two key factors in the solvent optimization. The addition of 20% in weight of dimethyl sulfoxide or of sulfolane permitted the cell charge and discharge at 5 mA/cm/sup 2/ at 130/sup 0/C. Peak current densities of 100 mA/cm/sup 2/ at 1 Volt were also obtained. The perspectives opened by solvent addition, led to the concept of ''electroactive solvent'' where the electroactive material itself solvates the sulfide sodium salt. In this respect, the alkoxyalkyl disulfides are promising candidates because of their combined low viscosity, high energy density and thermal stability. 42 refs., 47 figs., 4 tabs.

• Research Organization: Lawrence Berkeley Lab., CA (USA)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 5688117
• Report Number(s): LBL-24244; ON: DE88004559
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
250901* -- Energy Storage-- Batteries-- Design & Development
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400400 -- Electrochemistry
ALUMINATES
ALUMINIUM COMPOUNDS
BATTERY CHARGING
CATHODES
CHEMICAL REACTIONS
CORROSION
DATA
ELECTRIC BATTERIES
ELECTROCHEMICAL CELLS
ELECTRODES
ENERGY DENSITY
EXPERIMENTAL DATA
INFORMATION
METAL-NONMETAL BATTERIES
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
OXYGEN COMPOUNDS
POWER DENSITY
SALTS
SODIUM-SULFUR BATTERIES