PDF Publication Title:
Text from PDF Page: 227
it suggests that the same kind of reaction is occurring during the low plateau: i.e. formation of solids from soluble polysulfides, and no matter the temperature, it seems that Li2S formation always starts at the beginning of lower voltage plateau. (a) (b) Figure 6-26. Voltage profiles of different cycles obtained when decreasing the temperature from 0 °C to -40 °C, cycled at C/100 (a). Comparison of discharge profiles: recorded initially at -20°C (during 3rd cycle) and during 6th cycle, when the temperature came back to -20 °C (after being decreased to -30 °C and -40 °C during 4th and 5th cycle respectively). When the temperature got increased back to -20°C during the 6th cycle, the voltage profile displays almost identical behavior as the one obtained in 3rd cycle (also at -20°C). The lower discharge plateau comes back to exactly the same potential (1.98 V), as shown on Figure 6-26b. 6.7.2. Variation of the EIS parameters In-situ impedance spectroscopy was also performed at low temperature, in order to be able to differentiate more easily the different electrochemical processes. In regard to the changes of the high frequency region, electrolyte resistance evolution can be followed. As already described in the literature, lower temperature results in higher viscosity of the electrolyte251. Figure 6-27 shows how the electrolyte resistance changes between 25 °C and -30 °C. The same coin cell (with the composite electrode ‘S-on-NwC’; sulfur loading ~ 5.4 mgSulfur cm-2) was cycled during three cycles at C/100, while the temperature was changed at each cycle (-30 °C, -20 °C and 0 °C). It can be noticed that no matter the temperature applied at each cycle, the resistance evolution shows the same trend as previously discussed for 25 °C. Maxima of the resistance during discharge (R’max) and charge (R”max) correspond to the same moments on the cycling curve, i.e. beginning of the lower discharge plateau for the discharge process, which may correspond to the maximum concentration of the Li2S4 species in the Chapter 6: EIS and low temperature studies 223PDF Image | Accumulateur Lithium Soufre
PDF Search Title:
Accumulateur Lithium SoufreOriginal File Name Searched:
WALUS_2015_archivage.pdfDIY PDF Search: Google It | Yahoo | Bing
Sulfur Deposition on Carbon Nanofibers using Supercritical CO2 Sulfur Deposition on Carbon Nanofibers using Supercritical CO2. Gamma sulfur also known as mother of pearl sulfur and nacreous sulfur... More Info
CO2 Organic Rankine Cycle Experimenter Platform The supercritical CO2 phase change system is both a heat pump and organic rankine cycle which can be used for those purposes and as a supercritical extractor for advanced subcritical and supercritical extraction technology. Uses include producing nanoparticles, precious metal CO2 extraction, lithium battery recycling, and other applications... More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)