New nanostructured Li2S/silicon rechargeable battery with high specific energy.
Rechargeable lithium ion batteries are important energy storage devices; however, the specific energy of existing lithium ion batteries is still insufficient for many applications due to the limited specific charge capacity of the electrode materials. The recent development of sulfur/mesoporous carbon nanocomposite cathodes represents a particularly exciting advance, but in full battery cells, sulfur-based cathodes have to be paired with metallic lithium anodes as the lithium source, which can result in serious safety issues. Here we report a novel lithium metal-free battery consisting of a Li(2)S/mesoporous carbon composite cathode and a silicon nanowire anode. This new battery yields a theoretical specific energy of 1550 Wh kg(-1), which is four times that of the theoretical specific energy of existing lithium-ion batteries based on LiCoO(2) cathodes and graphite anodes (approximately 410 Wh kg(-1)). The nanostructured design of both electrodes assists in overcoming the issues associated with using sulfur compounds and silicon in lithium-ion batteries, including poor electrical conductivity, significant structural changes, and volume expansion. We have experimentally realized an initial discharge specific energy of 630 Wh kg(-1) based on the mass of the active electrode materials.
Yang
Yuan
Y
Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, USA.
McDowell
Matthew T
MT
Jackson
Ariel
A
Cha
Judy J
JJ
Hong
Seung Sae
SS
Cui
Yi
Y
D011211:Electric Power Supplies; D004566:Electrodes; D018020:Lithium Compounds / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry*; D036103:Nanotechnology / Q000295:instrumentation*; D016062:Porosity; D012825:Silicon / Q000737:chemistry*; D013440:Sulfides / Q000737:chemistry*; D013499:Surface Properties
D018020:Lithium Compounds; D013440:Sulfides; C550775:lithium sulfide; D012825:Silicon