Dear Colleagues,
We invite you to submit an abstract to "Symposium VI-B: Energy Materials" at the 54rd Annual Technical Meeting of the Society of Engineering Science: SES2017. More information on the symposium can be found at this link or at the bottom of this message.
Dear Colleagues,
We invite you to submit an abstract to "Symposium VI-B: Energy Materials" at the 54rd Annual Technical Meeting of the Society of Engineering Science: SES2017. More information on the symposium can be found at this link or at the bottom of this message.
We measure stresses that develop in sputter-deposited amorphous Ge thin films during electrochemical lithiation and delithiation. Amorphous LixGe electrodes are found to flow plastically at stresses that are significantly smaller than those of their amorphous LixSi counterparts. The stress measurements allow for quantification of the elastic modulus of amorphous LixGe as a function of lithium concentration, indicating a much-reduced stiffness compared to pure Ge.
Silicon is a promising anode material for lithium-ion batteries due to its enormous theoretical energy density. Fracture during electrochemical cycling has limited the practical viability of silicon electrodes, but recent studies indicate that fracture can be prevented by taking advantage of lithiation-induced plasticity. In this paper, we provide experimental insight into the nature of plasticity in amorphous LixSi thin films. To do so, we vary the rate of lithiation of amorphous silicon thin films and simultaneously measure stresses.
Dielectric elastomer transducers are often subject to large tensile stretches and are susceptible to rupture. Here we carry out an experimental study of the rupture behavior of membranes of an acrylic dielectric elastomer (VHB 4905). Pure-shear test specimens are used to measure force-displacement curves, using samples with and without pre-cracks. We find that introducing a pre-crack into a membrane drastically reduces the stretch at rupture. Furthermore, we measure the stretch at rupture and fracture energy using samples of different heights at various stretch-rates. The stretch at rupture is found to decrease with sample height, and the fracture energy is found to increase with stretch-rate.
This paper has appeared in the Journal of Applied Physics and can be downloaded from:
