Optimum switching of a reversible electrochemical mirror device

A method for optimizing the mirror uniformity and switching speed of a reversible electrochemical mirror of the type including a mirror electrode, a counter electrode, and an electrolyte disposed between and in electrical contact with the mirror and counter electrodes, wherein the electrolyte contains cations of an electrodepositable mirror metal, comprising the steps of:

• applying a first positive voltage to the mirror electrode relative to the counter electrode so that mirror metal is dissolved from the mirror electrode at a first rate;
• and
• applying a second positive voltage less positive than the first positive voltage to the mirror electrode relative to the counter electrode so that additional mirror metal is dissolved from the mirror electrode at a second rate which is slower than the first rate,
• wherein the first positive voltage does not exceed a predetermined maximum drive voltage.

A method for optimizing the mirror uniformity and switching speed of a reversible electrochemical mirror of the type including a mirror electrode, a counter electrode, and an electrolyte disposed between and in electrical contact with the mirror and counter electrodes, wherein the electrolyte contains cations of an electrodepositable mirror metal, comprising the steps of:

• applying a first negative voltage to the mirror electrode relative to the counter electrode so that mirror metal is deposited onto the mirror electrode at a first rate, wherein the first negative voltage is a substantially safe voltage with respect to damage to the mirror electrode and breakdown of the electrolyte when no mirror metal is present on the mirror electrode;
• measuring the sheet resistance between two locations on the mirror electrode;
• measuring the current flowing between the mirror electrode and the counter electrode;
• determining the electrical resistance of the electrolyte between the mirror electrode and the counter electrode;
• and
• applying a second negative voltage more negative than the first negative voltage to the mirror electrode relative to the counter electrode so that additional mirror metal is deposited onto the mirror electrode at a second rate which is faster than the first rate,
• wherein the magnitude of the second negative voltage is the smaller of:
• a predetermined maximum drive voltage;
• the sum of the safe voltage and the electrolyte voltage drop, the latter being equal to the multiplication product of the measured current and the measured electrolyte resistance;
• and
• that which will cause the multiplication product of the measured sheet resistance and the measured current to be less than a predetermined maximum sheet IR drop.

A method for optimizing the mirror uniformity and switching speed of a reversible electrochemical mirror of the type including a mirror electrode, a counter electrode, and an electrolyte disposed between and in electrical contact with the mirror and counter electrodes, wherein the electrolyte contains cations of an electrodepositable mirror metal, comprising the steps of:

• applying a first positive voltage to the mirror electrode relative to the counter electrode so that mirror metal is dissolved from the mirror electrode at a first rate, wherein the first positive voltage does not exceed a predetermined maximum drive voltage;
• measuring the sheet resistance between two locations on the mirror electrode;
• measuring the current flowing between the mirror electrode and the counter electrode;
• determining the electrical resistance of the electrolyte between the mirror electrode and the counter electrode;
• and
• applying a second positive voltage less positive than the first positive voltage to the mirror electrode relative to the counter electrode so that additional mirror metal is dissolved from the mirror electrode at a second rate which is slower than the first rate, wherein the magnitude of the second positive voltage is the smaller of:
• the predetermined maximum drive voltage;
• the sum of a safe voltage with respect to damage to the mirror electrode and breakdown of the electrolyte when no mirror metal is present on the mirror electrode plus the electrolyte voltage drop, the latter being equal to the multiplication product of the measured current and the measured electrolyte resistance;
• and
• that which will cause the multiplication product of the measured sheet resistance and the measured current to be less than the predetermined maximum sheet IR drop.