Electrode materials for secondary batteries

More than 10 years have already passed since the possibility of using conductive polymers as electrode materials for secondary batteries was first demonstrated. Various conductive polymers have been investigated with... 

Electrically conducting polymers have been a subject of extensive studies in view of both academic interest and potential technological applications. This chapter describes the synthesis and properties of electrically conducting polymers and their applications as functional materials, such as electrode materials for secondary batteries, photoactive materials for photovoltaic devices, electrochromic materials, and materials for use in organic electroluminescent devices. 

LiCo02, an important electrode material for secondary lithium batteries, occurs in 2 polytypes, both of which have been investigated by Li and Co NMR at 3 magnetic fields (Siegel et al. 2001). Both polytypes show only 1 Li resonance corresponding to lithium in octahedral coordination with oxygen, with similar Li xq values (25-36 kHz for the 02 polytype and 31-39 kHz for the 03 polytype). 

The formation and dissociation of S-S bonds in poly(tricyanuric acid), which is proposed as electrode material for lithium batteries, has been studied [590,591]. The reversibility of the process essential for the use of this material in a secondary battery could be established. Further studies of battery materials have been reported [592, 593]. X-ray absorption near edge structure spectroscopy has been successfully employed in studies of inhibiting species in passive films and the adjacent electrolyte solutions. 

An Li-Al Alloy was investigated for use as a negative electrode material for lithium secondary batteries. Figure 41 shows the cycle performance of a Li-Al electrode at 6% depth of discharge (DOD). The Li-Al alloy was prepared by an electrochemical method. The life of this electrode was only 250 cycles, and the Li-Al alloy was not adequate as a negative material for a practical lithium battery. 

QDO, PDO, and related compounds are the subject of a great number of invention patents, particularly for its uses in material sciences. For example, QDOs were included in the formulation of modified unsaturated polymers and rubbers [174,175]. Polymers with a QDO substructure as monomeric unit were used to produce fibers, films, electrochromic elements, electrodes, semiconductors, and electrolyte solutions for secondary batteries [176-179]. 

The carbazole polymer poly(iV-vinylcarbazole) functions as a positive electrode material for a secondary lithium battery <85CC553>, and as a memory photoreceptor <91M1 204-0l>. The related poly[3-(3-bromocarbazol-9-yl)propyl]methylsiloxane (18) forms novel electrochromic films <89CC196>. Carbazole anions have b n used to initiate the polymerization of acrylates and methacrylates <95CC275>. The novel polymeric pyrrolocarbazole (19) displays physical properties similar to those of polyanilines. 

Sensors Actuator Electrode for Secondary Battery, Solid Electrolytic Capacitor or Supercapacitor Field Effect Transistor Electromagnetic Interference Absorbing Material... 

Sun YK et al (2006) Novel core-shell-structured Li[(Nio.8Coo.2)o.8(Nio.5Mno,5)o.2]02 via coprecipitation as positive electrode material for lithium secondary batteries. J Phys Chem B 110 6810... 

A considerabel numbers of papers on fundamental studies of polymer-coated electrodes were published in various journals (e.g., Synth. Met., J. Chem. Soc., J. Electro-anal. Chem., Electrochim. Acta, Makromol. Chem., Macromol. Symp. 8 (1987)) in the year after this manuscript was completed. In several companies applied research works are on the way to realize application of these unconventional materials. Recently secondary batteries (polyaniline/Li, polypyrrole/Li) were commercialized. Developments for practical uses on electrochromic display and sensors are also underway. 

The theoretical gravimetric capacity is the ratio of the amoimt of electricity which can theoretically be released by using all of the active material of an electrode or a secondary battery, to the mass of that active material. This value has to be calculated. For this reason, we sometimes find extremely high values, having nothing whatsoever to do with the reality of the situation, as is sometimes the case with lithium-air secondary batteries (see Chapter 10). 

Yan, H., Sokolov, S., Lytle, J.C., Stein, A., Zhang, F., and Smyrl, W.H. (2003) Colloidal-crystal-templated synthesis of ordered macroporous electrode materials for lithium secondary batteries. 

Fey GTK, Huang DL (1999) Synthesis, characterization and cell performance of inverse spinel electrode materials for lithium secondary batteries. Electrochim Acta 45 295-314... 

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