Capacity fading

Graphite electrodes, ethylene carbonate, propylene carbonate, capacity fading, surface films, morphology, AFM, passivation. 

Figure 10. Capacity fade of anodes based on different materials. 

As it is seen from the data of Figure 8, all modified materials have poor cycling performance their reversible capacities fade faster than the one of initial non-modified material, and become lower after the first 8-10 charge-discharge cycles. Thus, we can conclude that no positive effect is achieved by means of modification of the Carbon-Type material with bimetal tri-nuclear complex of Co(III)-Ni(II). 

Figure 11. Capacity fading of initial and modified Graphite-Type materials in course of continuous cycling.

The surface of Li(Ni0.4Co0.2Mn0.4)O2 was coated with amorphous aluminum oxide using Al-isopropoxide. The as-prepared and coated materials exhibited almost no differences in initial capacity and impedance. However, during the extended cycling, the uncoated material exhibited significant capacity fading. 

In addition to the problem with the lithium anode, a new factor contributing to the capacity fade surfaced as the oxidative decomposition of ether-based compounds on the cathode surf ace. Electro-... 

Almost during the entire 1990s. the main interest of the lithium ion research community was focused on electrolyte/anode interfaces while its cathode counterpart was overlooked until various lithium ion systems, especially those based on manganese spinel cathodes, were found to suffer power loss and capacity fade upon prolonged cycling or storage at elevated temperatures. Preliminary diagnostic studies... 

Unfortunately, TMP was found to be cathodically unstable on a graphitic anode surface, where, in a manner very similar to PC, it cointercalated into the graphene structure at 1.20 V and then decomposed to exfoliate the latter, although its anodic stability did not seem to be a problem. Eor this reason, TMP has to be used in amounts less than 10% with EC and other carbonates in high concentration in order to achieve decent performance in lithium ion cells. However, capacity fading caused by the increase of cell impedance cast doubt on the application of this flame retardant in a lithium ion cell. To avoid the poor cathodic stability of TMP on graphitic anodes, the possibility of using it with other amorphous carbon electrodes was also explored by the authors. ... 

Like all the phosphates investigated as cosolvents, TBP and TPP showed higher anodic stability, as confirmed by their cycling in lithium ion cells based on a LiNio.8Coo.2O2 cathode up to 4.2 V, and separate cyclic voltammetry tests also showed that they would not decompose anodically below 5.0 V on an inert working electrode. Little capacity fading was detected during the extended tests of TPP or TBP in full lithium ion cells up to 150 cycles. 

An application of thick-film printing technology for the fabrication of a Zn-Mn02 alkaline batteries [342] was also described. The mechanism of the capacity fade of rechargeable alkaline zinc-manganese cell was studied and discussed [343]. Zinc electrode with addition of several oxides (HgO, Sb203) for alkaline Zn-Mn02 cells [344] was also studied. 

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