Russia has designs for an inflatable space station module. Wrapped into multilayered synthetic skin instead of metal, the expandable module could be attached to the Russian part of the International Space Station and inflated like a beach ball, providing greater comfort for the crew and extra room for yet-to-be-disclosed experiments.
Russian space web also has details of the russian inflatable space station module.
During 2012, RKK Energia evaluated two basic sizes of the inflatable module, which could be launched either on the Soyuz-2-1b rocket or on the Proton-M and Angara-A5 rockets.
During 2013 and 2014, RKK Energia and its contractors planned to build a one-third-scale prototype of the module for ground tests.