In order to assess the ion transport properties of alternative non-flammable electrolytes in a typical commercial Li-ion battery cell, we have measured the ionic conductivity s ion and the lithium-ion transference number under anion-blocking conditions, t ABC Li þ , for two classes of highly concentrated battery electrolytes: (i) Mixtures of the ionic liquid N-methyl-N-propylpyrrolidinium bis(fluorosulfonyl)imide (Pyr 13 FSI) with different amounts of the lithium bis(fluorosulfonyl)imide (LiFSI), and (ii) a solvate ionic liquid consisting of an equimolar mixture of tetraglyme (G4) and LiFSI. Together with previously published data on the solvate ionic liquid G4/LiTFSI (1 : 1), the obtained Li + ion transport data was used to estimate the overall resistance and the resulting maximum cycling rate of a commercial 10 Ah Li-ion pouch cell containing these alternative electrolytes. Our results suggest that Pyr 13 FSI/LiFSI mixtures would allow for maximum charging/discharging rates close to 1 C, while the solvate ionic liquids would only support maximum rates of about 0.3 C.
Evaluating the continuous-wave performance of AlGaInP-based red (667 nm) vertical-cavity surface-emitting lasers using low-temperature and high-pressure techniques Appl. Phys. Lett. 78, 865 (2001); 10.1063/1.1342049 6.1 W continuous wave front-facet power from Al-free active-region (λ=805 nm) diode lasers Appl.
The variable stripe-length method is considered a powerful yet easily implemented approach to measure the optical material gain of a semiconductor sample. However, the results obtained with this method are not as straightforward to interpret as originally suggested. Here, we discuss the general validity of the method by calculating the influence of carrier depletion on the emission of the sample—and thus the extracted gain—on the basis of a semiclassical description. We find that the method must only be applied within a narrow parameter window, and that even then, unreliable values may be obtained.
Spatially resolved photocurrent-spectroscopy and spatially resolved current-voltage characteristics are introduced as new methods to characterize solar cells. A combination of these two methods is shown to localize and characterize deficiencies and structural damages in processed solar cells with high spatial resolution. The local external and internal quantum efficiencies as well as the local characteristic parameters of the p-n junction like the short circuit current, the saturation current, the ideality factor, and the optically induced shunt resistance can be determined quantitatively. Both, a slab of a damaged and an undamaged (GaIn)(NAs) concentrator solar cell, are used as test structures. Upon these test structures domains with a high concentration of impurities in the crystal structure and structural imperfections in the upper contact region are identified and analyzed. Additional numerical simulations prove the reliability and show limits of the methods.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.