We studied the changes in the electronic structure of induced by deintercalation using and X‐ray absorption spectroscopy. The mean probing depth of this technique is . The results were analyzed using atomic multiplet and band structure calculations. The spectrum shows that the ions in are in a trivalent low‐spin state. The spectra of deintercalated show only minor changes as a function of concentration. The absence of changes indicates that the ions remain mostly unaffected by deintercalation. In particular, the ions in deintercalated are not oxidized to a tetravalent state as normally assumed. The spectra of deintercalated show an increase in the absorption intensity below threshold; this absorption increase indicates that the ions in are reduced upon deintercalation. ©2000 The Electrochemical Society