(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 m ∙ Ah/g, which is the number of milliamperes delivered by 1 g of material for 1 hour. How many coulombs are in 1 mA ∙ h?
(c) Show that the theoretical capacity of the battery is 274 mA∙ h/g LiCoO2.
(d) A Li+-ion battery can deliver 140 mA ∙ h/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 W ∙ h/g. A Li+-ion battery delivers 140 mA ∙ h/g LiCoO2 at 3.7 V. Express the energy storage as W ∙ h/g LiCoO2.