The number of publicly accessible US plug-in vehicle charging stations rose about 30 percent this year, as more retailers looked to attract potential customers by giving drivers the chance to charge up their Nissan Leaf and Chevrolet Volt plug-in vehicles while shopping.

There were about 6,770 public charging stations across the country as of Christmas Day, up from about 5,200 at the end of last year, according to official US Department of Energy figures. California accounted for 1,475 of those stations, about 22 percent of the country's total. Texas had 488 stations available to the public, while Florida had 398. Washington State and Oregon had 386 and 349 public charging stations, respectively, as their state governments encouraged more stations along US highways.

Among retailers, Walgreens continued to be the most aggressive with its station deployment, boasting 389. Kohl's had 62 stations while Whole Foods is home to 41. These retailers are responding to a plug-in vehicle market whose growth continues to outpace overall vehicle sales. Through November, US plug-in vehicle sales were up 61 percent from a year earlier to about 69,400 units, and that doesn't include the approximately 19,000 Model S sedans Tesla Motors likely sold during the first 11 months of the year (Tesla doesn't disclose monthly sales figures).