Monitoring method and system of metal ions or oxygen ions applicable to high concentration non-aqueous electrolyte

A method to monitor the concentration of metal ions or oxygen ions in a non-aqueous electrolyte, the method comprising:

• a first step of applying a constant potential to a working electrode put in said non-aqueous electrolyte to measure the current with respect to the constant potential;
• a second step of varying the constant potential between an oxidation potential and a reduction potential applied to the working electrode while maintaining the concentration of the metal ions or oxygen ions in the non-aqueous electrolyte;
• a third step of detecting a linear relationship between the concentration of the metal ions or oxygen ions in the non-aqueous electrolyte and the current by repeatedly performing the first step and the second step, wherein the concentration of the metal ions or oxygen ions is changed each time a combination of the first step and the second step is repeated;
• and
• a fourth step of calculating the concentration of the metal ions or oxygen ions in the non-aqueous electrolyte in pyroprocessing of the non-aqueous electrolyte by using the linear relationship;
• wherein when repeating the first and second steps, a constant potential is applied to the working electrode the magnitude of the constant potential is increased or decreased by stages, in order to sequentially measure a reduction current and an oxidation current.

A method to monitor the concentration of metal ions or oxygen ions in a non-aqueous electrolyte, the method comprising:

• a first step of applying a potential to a working electrode put in said non-aqueous electrolyte to measure the current with respect to the potential;
• a second step of varying a potential applied to the working electrode while maintaining the concentration of the metal ions or oxygen ions in the non-aqueous electrolyte;
• a third step of detecting a linear relationship between the concentration of the metal ions or oxygen ions in the non-aqueous electrolyte and the current by repeatedly performing the first step and the second step, wherein the concentration of the metal ions or oxygen ions is changed each time a combination of the first step and the second step is repeated;
• and
• a fourth step of calculating the concentration of the metal ions or oxygen ions in the non-aqueous electrolyte in pyroprocessing of the non-aqueous electrolyte by using the linear relationship;
• wherein in the first step and the second step, a potential allowing for the metal ions to be reduced is applied in the non-aqueous electrolyte to precipitate the metal ions, and the potential is subsequently increased to dissolve the metal ions, and
• wherein in order to form a meniscus to constantly maintain an area of the working electrode in contact with the non-aqueous electrolyte, the working electrode is raised to the surface of the non-aqueous electrolyte.

A monitoring method of metal ions and oxygen ions comprising:

• applying a potential while changing concentration of a solute in a non-aqueous electrolyte to obtain a correlation of a current with the potential in each concentration, by using any one of a repeating redox method in which a reduction potential having a constant magnitude and an oxidation potential having a constant magnitude are repeatedly applied, a multi-step redox method in which a constant potential is changed by stages, and a redox scanning method in which a potential is changed from a potential in which a solute is reduced and precipitated to an oxidation direction;
• detecting information regarding a current change by using any one of the repeating redox method, the multi-step redox method, and the redox scanning method during an electrolytic reduction process of the non-aqueous electrolyte;
• and
• calculating metal ions concentration or oxygen ions concentration in the non-aqueous electrolyte during the electrolytic reduction process by using the correlation and the information regarding the current change.

A monitoring system comprising:

• a power supply device including an oxidation electrode and a reduction electrode to apply a potential in a non-aqueous electrolyte;
• a sensor device having a working electrode, a counter electrode, and a reference electrode put in the non-aqueous electrolyte to obtain current information with respect to the potential, and a potentiostat connected to the working electrode, the counter electrode, and the reference electrode;
• an adjusting device configured to raise the working electrode to adjust a height of the working electrode to form a meniscus with the non-aqueous electrolyte;
• and
• a calculation unit configured to calculate concentration of metal ions or oxygen ions of the non-aqueous electrolyte during pyroprocessing of the non-aqueous electrolyte by using a linear relationship between the concentration of the metal ions or oxygen ions in the non-aqueous electrolyte and the current.