Rocking chair cell

Beginning in the early 1980s [20, 21] metallic lithium was replaced by lithium insertion materials having a lower standard redox potential than the positive insertion electrode this resulted in a "Li-ion" or "rocking-chair" cell with both negative and positive electrodes capable of reversible lithium insertion (see recommended papers and review papers [7, 10, 22-28]). Various insertion materials have been proposed for the anode of rechargeable lithium batteries,... 

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.

As a future development, realization of monolithic rocking chair cells may be one option [1]. A common network between the electrolyte and electrode materials would provide a continuous matrix for the lithium cation transfer from the electrode to the electrolyte or vice versa, and would consequently reduce the interfacial charge transfer resistance (Fig. 2.12). 

The crucial factor in this battery is that both electrodes are able to act as hosts for the Li+ ions, and the system has been termed a rocking-chair cell to reflect the fact that the Li ions rock back and forth between the two host materials during charging and discharging. Lithium-ion batteries have applications in, for example, laptop and notebook computers, mobile phones and portable CD players, and have potential use in electric cars. 

Rocking-chair cells LiMnjOyelect./carbon LiCoOj/elect./carbon LiNiOj/elect./carbon... 

The concept of lithium rocking-chair cells or lithium-ion batteries (LiBs) is not new. It has been proposed in the late 1970s by Armand who suggested to use two different intercalation compounds as a positive and negative electrode, in the so-called rocking-chair battery, the lithium ions being transferred from one side to the other [35]. Practically they were demonstrated in the early 1980s [36]. 

For comparison Modern lithium rocking chair cells work at a ceU voltage of 4V over 1000 cycles with energy densities exceeding 100 Wh/kg [698]. 

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