Cathodes of lithium-ion batteries

CARBONS IN THE CATHODES OF LITHIUM-ION BATTERIES ALTERNATIVE FORMS OF Mn02, CATHODE / CARBON MODELING... 

Chebiam, R.V., Kannan, A.M., Prado, F., and Manthiram, A., Comparison of the chemical stability of the high energy density cathodes of lithium-ion batteries, Electrochem. Commun., 3, 624, 2001. 

E.M. Garcia et al, "Electrochemical Recycling of Cobalt from Spent Cathodes of Lithium-ion Batteries Its Application as Coating on SOFC Interconnects," Journal of Applied Electrochemistry, Vol 41, 11, 2011, 1373-1379. 

The effectiveness of carbon nanotubes as conductive filler to cathode of lithium ion batteries (Fig. 17) was demonstrated by adding small amounts of both carbon nanotubes and acetylene blacks to LiCoOa-based active materials [77]. The merits of using carbon nanotubes together with acetylene blacks as cathode fillers include not only the enhancement of the electrical and the thermal properties of the electrode, but also the enhancement of the density of the electrode and the shortening of the electrolyte absorption time. We envisage that the use of carbon nanotubes as multi-functional fillers will increase in both cathode and anode materials for lithium ion secondary batteries. 

The design of lithium ion batteries has been a great achievement toward overcoming this defect. In these rechargeable batteries, a carbon matrix material is used instead of hthium as the negative electrode which, during charging, takes up hthium ions by cathodic intercalation ... 

There is no question that the development and commercialization of lithium ion batteries in recent years is one of the most important successes of modem electrochemistiy. Recent commercial systems for power sources show high energy density, improved rate capabilities and extended cycle life. The major components in most of the commercial Li-ion batteries are graphite electrodes, LiCo02 cathodes and electrolyte solutions based on mixtures of alkyl carbonate solvents, and LiPF6 as the salt.1 The electrodes for these batteries always have a composite structure that includes a metallic current collector (usually copper or aluminum foil/grid for the anode and cathode, respectively), the active mass comprises micrometric size particles and a polymeric binder. 

Sotowa C, Origi G, Takeuchi M, Nishimura U, Takeuchi K, Jang IJ, Kim YJ, Hayashi T, Kim YA, Endo M, Dresselhaus MS. The reinforcing effect of combined carbon nanotubes and acetylene blacks on the cathode electrode of lithium ion batteries. ChemSuschem 2008 1 911-915. 

Table 6.1 Summary of cathode and anode materials used for different types of lithium-ion batteries (all reproduced with permission from [14], copyright 2008, Wiley-VCH Verlag GmbH Co. KGaA]...

Manganese spinel cathode materials, although inferior to layered compounds, are cheap and rich in resources. Therefore, it is suitable as a cathode material in large-scale use of lithium-ion batteries. This spinel compound has been used for cellular phones produced by NEC Co. and for EV and hybrid EV produced by Nissan Co. Ltd. However, its share in the market of cathode material is relatively... 

The procedure developed by Tanaka Chemical Co. is in the forefront of these methods. This company occupies almost a monopoly position as a supplier of cathode materials for the nickel-cadmium battery and the nickel-metal hydride battery. Metal hydroxides have been prepared via an amine complex. Spherical material is produced by adjusting the pH of the aqueous solution, the aging temperature, and the introduction rate of the reactant. This technology is applied to the cathode material of lithium-ion batteries and has been patented. Since precipitates with homogeneous distribution of various elements can be obtained using the co-precipitation technique. 

The layered LiNiO is expected to be a cathode material for the next generation of lithium-ion battery. Figure 16.1 shows the relationship between discharge capacity and voltage for cathode materials for the lithium-ion battery. It means that LiNiO has a higher capacity compared with other materials. In spite of this, LiNiO compounds have not been used in commercially available lithium-ion batteries. It is thought that LiNiOj presents the following potential problems ... 

Toda Kogyo Corporation is promoting the development for each cathode material for lithium-ion batteries depending on their use for example, LiCoO for notebook personal computers and cellular phones LiMn O for hybrid electric vehicles (HEV) and LiNiO for high-capacity batteries. Special efforts are being made in the improvement of the above problems, i.e., cycle characteristics and thermal stability, for LiNiOj, so that this compound can be included in the market trend of lithium ion batteries. This chapter presents the results of the process development to improve the above-mentioned problem. 

These results indicate that the problems mentioned in the first section of this chapter can be resolved, and LiNiO can be considered to be a cathode material of lithium-ion batteries. 

L. Yang, B. Ravdel, B. L. Lucht, Electrolyte Reactions with the Surface of High Voltage LiNi0.5Mnl.5O4 Cathodes for Lithium-Ion Batteries, Electrochem. Solid-State Lett. 2010, 13,A95-A97. 

D nanoarchitectures came into focus of recent research [38]. Advantages of such well-defined, ion-electron conductive pathway-integrated 3D architectures are, in addition to the small areal footprint, the short transport lengths for ions in the solid-state electrode as well as between the anode and cathode. In lithium-ion batteries, the 3D design minimizes both distances and hence yields concomitant improvements in the achieved power density. Sophisticated 3D preparation techniques also hold great promise in fuel cells. 

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