The effects of processing on the structure and morphology of single-walled carbon nanotubes (SWNT) and their electrochemical intercalation with lithium were investigated. Purified SWNTs were processed by impact ball-milling and were electrochemically intercalated with lithium. The reversible saturation Li composition increased from Li1.7C6 in purified SWNTs to Li2.7C6 after 10 min of milling. The irreversible capacity decreased from Li3.2C6 to Li1.3C6. Electron microscopy, Raman and X-ray diffraction measurements indicated that ball-milling induced disorder within the bundles and fractured the nanotubes.