Solid electrolyte interphase on graphite Li-ion battery anodes studied by soft X-ray spectroscopy

• We have measured X-ray absorption and emission near the C Is edge of graphite electrodes cycled in lithium-ion battery cells. Resonantly excited emission spectra of graphite electrodes exhibit features characteristic of both highly oriented pyrolytic graphite as well as polycrystalline graphite. Spectra of three electrodes cycled in two different electrolytes are presented and compared with spectra of the pristine electrode. A solid electrolyte interphase(SEI) was detected on the electrochemically cycled electrodes. By the use of selective excitation, resonant X-ray emission spectra of the SEI-species were obtained and compared to spectra of reference compounds. The SEI on the cycled graphite anode was shown to comprise lithium oxalate (Li2C2O4), lithium succinate (LiO2CCH2CH2CO2Li) and lithium methoxide (LiOCH3).

Subject headings

NATURVETENSKAP  -- Kemi -- Oorganisk kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences -- Inorganic Chemistry (hsv//eng)

Keyword

Inorganic chemistry

Oorganisk kemi

Publication and Content Type

ref (subject category)

art (subject category)