Current-Producing and Other Processes in Lithium Ion Batteries

Lithium ion batteries proved to be very advantageous. Their development was very rapid and their specific characteristics more than doubled in 10-15 years, while their cost decreased fivefold. Their production scale grew at a tremendous rate. Current annual production is several billions of pieces. It was the large-scale production of lithium ion batteries that determined the modem production rate of such devices as cell phones, digital photo and video cameras, notebooks, and wireless power tools. 

2 CURRENT-PRODUCING AND OTHER PROCESSES IN LITHIUM ION BATTERIES 

In the case of lithium intercalation into well-resolved graphite structures, the thermodynamically stable LiCg compound can be obtained. Activity of lithium in this compound is unity, as the potential of such a compound is usually equal to the potential of a lithium electrode. Therefore, the equation of intercalation-deintercalation is usually as follows  

Lithium is intercalated into amorphous structures at more positive potentials generally, in the range of potentials from 0.9 to 0.0 V. The dependence of potentials on the value of x in these cases is a smooth curve corresponding to a uniform system. Nongraphitized structures are not laminated under intercalation of lithium. 

Attempts were made to discover the correlation between the crystalline structure of carbonaceous materials and their capability to reversibly intercalate lithium. This correlation has not been definitely established, but still, one can assume as a certain general principle that the optimum materials would contain an amorphous matrix with inclusions of a mesophase nuclei of graphite crystallites. Such materials are various cokes, pyrographite, and products of pyrolysis (carbonization) of various polymers. For practical purposes, the industry mastered some special materials providing high characteristics of negative electrodes in lithium ion batteries. The most popular material is manufactured by the Japanese company of Osaka Gas Co. under the name of mesocarbon microbeads, MCMB it represents the carbonization product of pitchy resins under a certain temperature regime. 

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