Mitigating strategy in lithium dendrite formation in a Li–S cell in accelerated cycling tests
Autor: | Vladimir Kolosnitsyn, S. E. Mochalov, Elena Karaseva, D. V. Kolosnitsyn, Alexey Ivanov, E. Kuzmina, Ramachandran Vasant Kumar |
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Rok vydání: | 2019 |
Předmět: |
Materials science
General Chemical Engineering chemistry.chemical_element 02 engineering and technology Calorimetry Electrolyte 010402 general chemistry 021001 nanoscience & nanotechnology Electrochemistry 01 natural sciences 0104 chemical sciences Corrosion Dendrite (crystal) chemistry Chemical engineering Heat generation Electrode Lithium 0210 nano-technology |
Zdroj: | Electrochimica Acta. 327:135007 |
ISSN: | 0013-4686 |
Popis: | Electrochemical impedance analysis, in-situ dilatometry, in-situ electrochemical calorimetry and ex-situ SEM have been shown to be effective diagnostics for studying formation of lithium dendrites in cells. Effect of lithium polysulfides present in the electrolyte in a Li–S cell, on the suppression of fine-dispersed heterogenous non-planar lithium dendrite precipitations during cycling of lithium symmetric cells was studied in accelerated DC cycling tests by a combination of the above techniques. It is shown that deliberate incorporation of lithium polysulfides in electrolyte solutions leads to decreasing rate of accumulation of fine-dispersed lithium (dendrite precipitations) on the surface of a lithium electrode which results in increasing the cycle life of lithium symmetric cells by 200–250% in accelerated tests, thus enhancing safety. It is demonstrated that electrochemical dilatometry and EC calorimetry are sensitive to changes on the surface of lithium electrode and can be used for early identification of dendrite formation during cycling of lithium electrodes. In-situ electrochemical dilatometry can not only identify formation of Li dendrites at early stages but also quantify the growth rate. The presence of high surface area lithium is more corrosive towards the electrolyte and can be monitored by the use of in-situ EC calorimetry for heat generation by corrosion during a cycle. Cycle life is limited by evenness/continuity of electrolyte solution in cell, which must essentially fill internal volume of the cell (all the pores without leaving any “dry area”). |
Databáze: | OpenAIRE |
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