Table 1.
Comparison of different contributions to the measured internal resistance, Ri(exp), of thermocell under various experimental conditions. The ohmic resistance, RO, values were determined via AC conductivity measurements while the mass transfer resistance, RMT, values were theoretically calculated. The charge transfer resistance, RCT, was taken from literature (see text). Note that RMT cannot be defined in the cold-over-hot configuration due to the presence of convection.
| Φ | Ri (Ω) (exp) | RO(Ω) (exp) | RMT(Ω) (calc) | RCT(Ω) [57] |
|---|---|---|---|---|
| 3 mM redox—Hot over cold configuration | ||||
| 0 | 34,000 ± 1000 | 700 | ~27,000 | <<1 |
| 0.5% vol. | 12,900± 1000 | 300 | ~27,000 | <<1 |
| 400 mM redox—Hot-over-cold configuration | ||||
| 0 | 438 ± 6 | 9.75 ± 0.5 | ~200 | <<1 |
| 0.5% vol. | 219 ± 5 | 9.75 ± 0.5 | ~200 | <<1 |
| 400 mM redox—Cold-over-hot configuration | ||||
| 0 | 23 ± 1 | 9.75 ± 0.5 | - | <<1 |
| 0.5% vol. | 23 ± 1 | 9.75 ± 0.5 | - | <<1 |