Question

Application note on temperature effects on aluminium electrolytic capacitors

Answer 1

As the temperature of the electrolyte decreases, its viscosity increases resulting in a reduced electrical conductivity. ... When operating at -400C, low-voltage aluminum electrolytic capacitors with a low temperature rating of -550C exhibit a capacitance loss of between -10% and -20%.

Answer 2

• The properties of the liquid electrolyte that are considerably affected by temperature variations include electrical conductivity and viscosity.
• The electrical conductivity of the electrolyte increases with an increase in temperature and reduces with a decrease in temperature.
• Temperature variations have more effect on the characteristics of aluminum electrolytic capacitors than on other types of capacitors.
• Some of the functional parameters for aluminum electrolytic capacitors that are considerably affected by changes in temperature include capacitance, equivalent series resistance (ESR), tangent delta, leakage current, and impedance.