On the Oxidation State of Manganese Ions in Li-Ion Battery Electrolyte Solutions.
Anjan BanerjeeYuliya ShilinaBaruch ZivJoseph M ZiegelbauerShalom LuskiDoron AurbachIon C HalalayPublished in: Journal of the American Chemical Society (2017)
We demonstrate herein that Mn3+ and not Mn2+, as commonly accepted, is the dominant dissolved manganese cation in LiPF6-based electrolyte solutions of Li-ion batteries with lithium manganate spinel positive and graphite negative electrodes chemistry. The Mn3+ fractions in solution, derived from a combined analysis of electron paramagnetic resonance and inductively coupled plasma spectroscopy data, are ∼80% for either fully discharged (3.0 V hold) or fully charged (4.2 V hold) cells, and ∼60% for galvanostatically cycled cells. These findings agree with the average oxidation state of dissolved Mn ions determined from X-ray absorption near-edge spectroscopy data, as verified through a speciation diagram analysis. We also show that the fractions of Mn3+ in the aprotic nonaqueous electrolyte solution are constant over the duration of our experiments and that disproportionation of Mn3+ occurs at a very slow rate.
Keyphrases
- solid state
- ion batteries
- room temperature
- ionic liquid
- induced apoptosis
- transition metal
- metal organic framework
- cell cycle arrest
- high resolution
- organic matter
- electronic health record
- quantum dots
- magnetic resonance imaging
- single molecule
- cell death
- capillary electrophoresis
- ms ms
- machine learning
- aqueous solution
- visible light
- water soluble