Thermocells of carbon material electrodes and its performance characteristics

Thermoelectrochemistry using conventional and novel gelled electrolytes in heat-to-current thermocells

“…Manda et al reported a 'thermocell' using an agar agar gelled electrolyte. [23] However, no comparison was made with non-gelled systems, and only ferricyanide was employed, so balanced redox processes could not have occurred without ferrocyanide present. This likely accounts for why 'Seebeck coefficients' well outside of expected and reasonable values were reported, and which fluctuated randomly e.g.…”

High Efficiency Graphene Coated Copper Based Thermocells Connected in Series

“…The energy conversion efficiency is calculated [18] using Equation (2) for different loads at ∆T = 60 • C as shown in Figure 4, that the maximum energy conversion efficiency of the fabricated graphene coated copper based thermocell (3 cells in series) to be 3.59% at a load of 100 mV/s for T = 60 • C which is 2.5 times higher than graphene based thermocell [19], 134 times higher than the energy conversion efficiency of 0.027% attained at 60 • C when 5 cells in series with activated charcoal as electrode material was used [20], 45 times higher than the energy conversion efficiency of 0.085% at 60 • C attained from flat cell with CNT as electrode material [20], 8.2 times higher than energy conversion efficiency of 0.44% at 60 • C attained from MWCNT based flat thermocells and 6.4 times higher than the maximum energy conversion efficiency of 0.56% attained from cylindrical CNT aerogel sheets based thermocells [18]. The energy conversion efficiency (η r ), relative to the Carnot efficiency of a heat engine is given by,…”

“…At T = 60 • C, V oc was 70.4 mV and j sc stabilized at 55.7 A/m 2 in the coin like thermocell with MWCNT forest electrodes [10]. The power density of 1.68 mW/m 2 was attained at 60 • C when 5 cells in series with activated charcoal as electrode material was used [20]. In the previous work [19] for single cell, the maximum current and power density obtained were 0.63 A/m 2 , 0.19 W/m 2 at T = 50 • C indicating that graphene coated copper could be an efficient electrode system.…”

“…Carnot efficiency of 0.98% attained at 60 • C for 5 cells in series with activated charcoal as electrode material [20]. It could be clearly seen from Figure 4, that the resulting maximum relative carnot efficiency to be η r = 20.2% at T = 60 • C for fabricated graphene based thermocell (3 cells in series) which is 12.9 times higher than the single cell graphene based thermocell [19] and 20.7 times higher than activated charcoal based devices reported in the literature [20].…”

Thermocells for Hybrid Photovoltaic/Thermal Systems

“…Although thermoelectric devices have been long investigated for the direct conversion of thermal to electrical energy with many exciting advances having been made [42], device performance relative to cost has limited its application in waste heat recovery [23]. Integrating thermocell technology into PV/T systems can offer major advantages that can help mitigate these cost issues, as suggested by the comparisons of Wh/dollar of solar cells and thermocells [26,43]. Therefore, we believe that the cost-effectiveness and simple deployability of thermocells, such as the one presented in this paper, can lead to their importance in the practical and large-scale implementation of PV/T systems because remarkable advances can be made in thermocell performance.…”