Intercalation-deintercalation reaction oxides

Lithium ion can be intercalated, more or less, into most kinds of carbon, and the resulting lithiated carbons show extremely negative electrochemical potentials close to that of the metallic lithium electrode. The reversible intercalation/deintercalation reactions overcome the problem of dendrite formation of lithium and provide dramatic improvements in safety and cycleability. The carbon anodes are combined with non-aqueous electrolyte solutions and lithium-transition metal oxides such as LiCoOg as cathodes to fabricate 4 V-class LIBs. Only lithium ion moves back and forth between the cathode and the anode upon charging and discharging, which give rise to a potential difference of about 4 V between the two electrodes. The name, "lithium-ion" batteries came from this simple mechanism. 

This may lead to the irreversible changes in the material, caused by partial oxidation of graphite, loss of reversibility of the system along with the efficiency of reaction for intercalation-deintercalation (1). 

Chemical relaxation methods can be used to determine mechanisms of reactions of ions at the mineral/water interface. In this paper, a review of chemical relaxation studies of adsorption/desorption kinetics of inorganic ions at the metal oxide/aqueous interface is presented. Plausible mechanisms based on the triple layer surface complexation model are discussed. Relaxation kinetic studies of the intercalation/ deintercalation of organic and inorganic ions in layered, cage-structured, and channel-structured minerals are also reviewed. In the intercalation studies, plausible mechanisms based on ion-exchange and adsorption/desorption reactions are presented steric and chemical properties of the solute and interlayered compounds are shown to influence the reaction rates. We also discuss the elementary reaction steps which are important in the stereoselective and reactive properties of interlayered compounds. 

When cationic guest atoms such as lithium, hydrogen, and sodium reversibly enter or leave the host oxide crystal, along with an accompanying electron flow but without any change in crystal structure, the reaction is referred to as intercalation/ deintercalation as follows [1, 2] ... 

Figure 1. Schematic description of a (lithium ion) rocking-chair cell that employs graphitic carbon as anode and transition metal oxide as cathode. The undergoing electrochemical process is lithium ion deintercalation from the graphene structure of the anode and simultaneous intercalation into the layered structure of the metal oxide cathode. For the cell, this process is discharge, since the reaction is spontaneous.

There are two theories developed to explain the processes for charge storage in MnC>2.197 One theory suggests that proton (H+) and alkali metal cations (C+), present in the electrolyte, can be reversibly intercalated into the bulk of Mn02 through a reduction reaction and deintercalated via an oxidation reaction 198... 

This type of Li battery has already widely diffused in the electronic consumer market, however for automotive applications the presence of a liquid electrolyte is not considered the best solution in terms of safety, then for this type of utilization the so-called lithium polymer batteries appear more convenient. They are based on a polymeric electrolyte which permits the transfer of lithium ions between the electrodes [21]. The anode can be composed either of a lithium metal foil (in this case the device is known as lithium metal polymer battery) or of lithium supported on carbon (lithium ion polymer battery), while the cathode is constituted by an oxide of lithium and other metals, of the same type used in lithium-ion batteries, in which the lithium reversible intercalation can occur. For lithium metal polymer batteries the overall cycling process involves the lithium stripping-deposition at the anode, and the deintercalation-intercalation at the anode, according to the following electrochemical reaction, written for a Mn-based cathode ... 

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