Thousands of Starbucks stores could soon draw folks who need more than just a cup of liquid energy. Procter & Gamble Co. plans to expand a pilot program that will allow customers of the nation’s largest coffee chain to wirelessly recharge their mobile phones.

If the national roll-out of P&G’s Duracell Powermat wireless battery chargers proves successful at Starbucks, other types of locations might jump on board. Think of any place where users of smartphones scramble to secure an electrical outlet…