Introduction Of Li-ion Battery
- May 03, 2018-
Li-ion batteries have an unmatchable combination of high energy and power density, making it the technology of choice for portable electronics, power tools, and hybrid/full electric vehicles. If electric vehicles (EVs) replace the majority of gasoline powered transportation, Li-ion batteries will significantly reduce greenhouse gas emissions. The high energy efficiency of Li-ion batteries may also allow their use in various electric grid applications, including improving the quality of energy harvested from wind, solar, geo-thermal and other renewable sources, thus contributing to their more widespread use and building an energy-sustainable economy. Therefore Li-ion batteries are of intense interest from both industry and government funding agencies, and research in this field has abounded in the recent years.
Yet looking to the future, there are many who doubt that Li-ion batteries will be able to power the world's needs for portable energy storage in the long run. For some applications (such as transportation and grid) Li-ion batteries are costly at present, and a shortage of Li and some of the transition metals currently used in Li-ion batteries may one day become an issue . At the same time, Li-ion batteries have certain fundamental advantages over other chemistries. Firstly, Li has the lowest reduction potential of any element, allowing Li based batteries to have the highest possible cell potential. Also, Li is the third lightest element and has one of the smallest ionic radii of any single charged ion. These factors allow Li-based batteries to have high gravimetric and volumetric capacity and power density. Finally, although multivalent cations allow for higher charge capacity per ion, the additional charge significantly reduces their mobility. Given that ionic diffusion in the solid electrodes is often the rate-limiting factor for battery power performance, this presents an enormous hurdle for the development of such alternative chemistries.