A lithium-ions accumulator works at 40 C with a voltage of 3.7 V and a continuous...

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A lithium-ions accumulator works at 40 °C with a voltage of 3.7 V and a continuous current of 3 A. The redox process is reported below: xLi → xLi* + xe Li₁-xC0O₂ + xLi* + xe → LiC00₂ The graphitic electrode contains 70 % of Li ions and operates until reaching 0.4 mol of such ions at discharge. Such battery is part of a hybrid system with a 5-cells PEM stack, useful for recharge purposes. Calculate: a. the time [h] for a single discharge process b. the Gibbs free energy of a single PEM cell c. the working current density of the PEM stack d. the hydrogen and air volumetric consumption in the PEM stack [NL/min] e. the exchange current density Useful data: Eo: 1.18 V (single cell) active area (PEM): 45 cm² activation loss: 0.3 V crossover loss: negligible concentration loss: 0.08 V total internal resistance (PEM): 20 cm² [1] [1] [1] [1] [1] A lithium-ions accumulator works at 40 °C with a voltage of 3.7 V and a continuous current of 3 A. The redox process is reported below: xLi → xLi* + xe Li₁-xC0O₂ + xLi* + xe → LiC00₂ The graphitic electrode contains 70 % of Li ions and operates until reaching 0.4 mol of such ions at discharge. Such battery is part of a hybrid system with a 5-cells PEM stack, useful for recharge purposes. Calculate: a. the time [h] for a single discharge process b. the Gibbs free energy of a single PEM cell c. the working current density of the PEM stack d. the hydrogen and air volumetric consumption in the PEM stack [NL/min] e. the exchange current density Useful data: Eo: 1.18 V (single cell) active area (PEM): 45 cm² activation loss: 0.3 V crossover loss: negligible concentration loss: 0.08 V total internal resistance (PEM): 20 cm² [1] [1] [1] [1] [1]

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Answer a The time for a single discharge process is 40 hours b The Gibbs free energy of a single PEM cell is 054 V c The working current density of th... View the full answer