A battery includes an anode, a cathode, and an electrolyte disposed between the anode and the cathode. The cathode includes a hollow structure defining an internal volume and a sulfur-based material disposed within the internal volume. A characteristic dimension of the internal volume is at least 20 nm, and the sulfur-based material occupies less than 100% of the internal volume to define a void.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
 This invention was made with Government support under contract DE-AC02-76SF00515 awarded by the Department of Energy. The Government has certain rights in this invention.