Volta is the sixth studio album by Icelandic singer Björk, released on 1 May 2007 by One Little Indian Records. A wide array of artists collaborated with Björk on material for the album, including longtime collaborator Mark Bell, along with new producers Timbaland and Danja.The album received positive reviews upon its initial release, and is Björk's first and only album to reach the top 10 on the US Billboard 200, peaking at number nine. Volta spent nine weeks at number one on the US Top Electronic Albums chart and in the first three months of release sold over half a million copies worldwide. In the United Kingdom it was certified Silver. The lead single, "Earth Intruders", reached number 67 on the UK Official Download Chart, and number 78 on the main UK Singles Chart, while the remix EP later charted on its own at number 150. In the United States, the song became her second entry on the US Billboard Hot 100 at number 84. Volta was nominated for Best Alternative Music Album at the 50th Annual Grammy Awards.The album was re-released in June 2009 in expanded versions, under the name Voltaïc. There were five separate versions of related material from Volta. The full version included a CD of 11 songs performed live at the Olympic Studios, a DVD of live performances in Paris and Reykjavík during the Volta tour, a second DVD of the Volta music videos, videos of the top ten runners-up from the "Innocence" video contest, and a second CD of remixes from Volta's singles. The official worldwide release date of all editions was 23 June 2009. The artwork was nominated for an award at the 2010 Brit Insurance Design Awards. It was a collaboration between the German fashion designer Bernhard Willhelm and British fashion photographer Nick Knight. Björk went on an 18-month tour in support of the album, which was her first tour in four years.