First cycle loss

Winter M., Novak P. and. Monnier A. Graphites for Lithium-ion Cells The Correlation of the First-Cycle Loss with the Brunauer-Emmett-Teller Area. J. Electrochem. Soc., 145, 428-435 (1998). 

Clearly the rate of reaction declines in repeated cycles. However the decrease between cycle 2 and cycle 3 was considerably smaller than that between cycle 1 and cycle 2, indicating that loss of activity occurred primarily in the first cycle. This is due to loss of surface area as discussed later. 

At 50°C, a marked improvement was seen over the baseline cell, both in terms of more stable cycling, a higher rate capability, and less first cycle irreversible capacity loss. Reasons for the improvement in performance appear to be related to a lowering of the electrode material impedance and a smaller first cycle irreversible capacity by suppression of PC solvent cointercalation due to a de-solvation catalyzed by Cu metal. 

As discussed in the next section, lithiated carbon electrodes are covered with surface films that influence and, in some cases, determine their electrochemical behavior (in terms of stability and reversibility). They are formed during the first intercalation process of the pristine materials, and their formation involves an irreversible consumption of charge that depends on the surface area of the carbons. This irreversible loss of capacity during the first intercalation/deintercalation cycle is common to all carbonaceous materials. However, several hard, disordered carbons exhibit additional irreversibility during the first cycle, in addition to that related to surface reactions with solution species and film formation. This additional irreversibility relates to consumption of lithium at sites of the disordered carbon, from which it cannot be electrochemically removed [346-351],... 

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