After successful tests in Boston and Silicon Valley, Starbucks says it is ready for a nationwide rollout of Duracell Powermat wireless charging stations. As with the rest of its wireless charging plans, the rollout will be slow starting first with stores in the San Francisco Bay Area.

Starbucks says it will expand to other major markets across the country in 2015. Over time, the entire U.S. will go wireless via company-owned Starbucks locations and Teavana Tea Bar spots. Charging stations, dubbed Powermat Spots,' will be embedded in tables and counters at company stores.

But whether your phone will be compatible with Powermat Spots is another question. Duracell Powermat and Starbucks are part of the Power Matters Alliance, which uses a charging technology that is incompatible with Qi wireless charging.

Qi is currently a favorite among device makers and is used in phones such as the Nexus 5, LG G3, many Nokia Lumia phones, and Samsung's Galaxy S5--if you buy the official wireless charging back cover. Apple's iPhone is not compatible--at least not on its own.

And that's the good news: Many Starbucks junkies can buy PMA-compatible cases for their phones for powering up during latte sessions. They'll run you around $30 to $50.

By throwing in with Powermat technology, Starbucks is at the forefront of the emerging standards war for wireless charging. Three different organizations with various backers have lined up for the fight including the PMA, the Alliance for Wireless Power, and the Wireless Power Consortium--the group behind the Qi standard.

In February, the PMA and the AWP agreed to make their standards work together by including both specs in future charging products. Qi backers, however, are still going it alone.