Raman study of structural stability of LiCoPO4 cathodes in LiPF6 containing electrolytes

Micro-probe Raman spectroscopy investigation of LiCoPO4 composite electrodes performed after prolonged cycling in LiPF6 EC/DMC electrolyte solution revealed total structural degradation of the olivine structure of the electrodes. The electrodes cycled in the identical conditions but in the presence of the HF-scavenging glassy fiber (GF) separators retain their olivine structure unchanged. The reasons for this pronounced difference are discussed.

► Micro-probe Raman analysis of LiCoPO4 electrodes after cycling.
► Total structural degradation of LiCoPO4 electrodes cycled in LiPF6/EC/DMC electrolyte.
► HF-scavenging glassy fiber separators prevent destruction of olivine.