| 摘要 |
A redox flow (RF) battery capable of improving an energy density is provided. An RF battery 100 performs charge and discharge by supplying a positive electrode electrolyte and a negative electrode electrolyte to a positive electrode cell 102 and a negative electrode cell 103, respectively. Each of the positive electrode electrolyte and the negative electrode electrolyte contains a vanadium (V) ion as active material. At least one of the positive electrode electrolyte and the negative electrode electrolyte further contains another metal ion, for example, a metal ion such as a manganese ion that exhibits a higher redox potential than a V ion or a metal ion such as a chromium ion that exhibits a lower redox potential than a V ion. Even in cases where the RF battery 100 is charged until the state of charge reaches nearly 100%, side reactions such as generation of oxygen gas or hydrogen gas due to water decomposition and oxidation degradation of an electrode can be suppressed since the above-mentioned another metal ion contained together with the V ion is oxidized or reduced in the late stage of charge. Since the utilization rate of the V ion in the electrolyte can be increased by enhancing the state of charge, the energy density of the RF battery 100 can be improved as compared to the conventional RF batteries. |
