Lithium-ion battery. (a) Ideal formulas for the electrodes of the Li-ion battery

Chapter 13, Problem 13-11

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Lithium-ion battery. (a) Ideal formulas for the electrodes of the Li-ion battery described in the chapter opener are C6Li (FM 79.01) and LiCoO2 (FM 97.87). When the battery operates, C6Li is consumed and LiCoO2 is formed. Write a half-reaction for each electrode, assuming that x 1 in the reaction . (In fact, in real cells.) Which is the anode and which is the cathode? (b) Charge capacity of an electrode in a battery is expressed as mAh/g, which is the number of milliamperes delivered by 1 g of material for 1 hour. How many coulombs are in 1 mAh? (c) Show that the theoretical capacity of the battery is 274 mAh/g LiCoO2. (d) A Li-ion battery can deliver 140 mAh/g LiCoO2. What fraction of Li in the formula LiCoO2 is available? (e) Energy stored by a battery per unit mass of an electrode material is expressed as Wh/g. A Li-ion battery delivers 140 mAh/g LiCoO2 at 3.7 V. Express the energy storage as Wh/g LiCoO2. St