Constant-current discharging

Finally, Fig. 33 shows the results of constant current discharge experiments at a microtubular electrode and a control electrode containing the same amount of TiS 2. Note that at this discharge current density, the microtubular electrode delivers 90% of its theoretical capacity. In contrast, as would be expected, the control electrode delivers significantly less capacity. 

Fig. 11.5 Constant-current discharge curves (100 gA) at 25 °C for the cell Cu4MogSg/ Rb4Cui6l,Cli3/MS2 (Kanno et aU 1986).

Fig. 11.7 Constant-current discharge curves at 25 °C for the cell Cuj.gMogSv.g/ Rb4Cu,6l7Cl,3/Cuo.2Mo6S7.g (Kanno et of, 1987).

Fig. 11.12 Constant-current discharge curves for the cell Li/2.5LiI Li4P2S7/(TiS2+ 2.5LiI Li4P2S7) at 25°C (Akridge and Vourlis, 1986).

Fig. 6.14 Voltage profile for constant current discharge of a RENEWAL AA RAM cell. (By permission of Rayovac,)...

Fig. 6.15 Effect of charge-discharge cycles on discharge curve of a RENEWAL A A RAM cell, Constant current discharge at 50 m A. (a) Cycle 1, (b) cycle 5, (c) cycle 10, (d) cycle 25, (e) cycle 50. (By permission of Rayovac.)...

Fig. 6.18 Repetitive short discharge cycles for a RENEWAL AA RAM cell 400 mA constant current discharge for 10 minutes followed by standard recharge, (a) Cycles 1-4, (b) cycles 707-800, (By permission of Rayovac.)...

C (co) is the capacitance of the electrode (or the cell) the low frequency value of C (to) is the capacitance obtained during constant current discharge measurements. 

Temperature effect on capacity/25 mA constant current discharge to 0.9... 

Wang et al. [19] developed a new method of electrode preparation with a novel silica gel additive (NSGA) instead of the traditional Nafion polymer additive (TNPA) for PEMFCs. The performance of the two types of electrodes was compared using electrochemical impedance spectroscopy coupled with a polarization curve and constant-current discharge. Figure 6.20 shows the AC... 

Depending on applications, alkaline Zn/Mn02 batteries can be discharged under different conditions, such as constant current, constant resistance, and constant power. In case of the constant current discharge, the capacity utilization can be affected by the applied... 

The discharge mode of Ni-Cd batteries is dependent on their applications. The most common one is the constant-current discharge, in which the current can be changed from very low (e.g., in the case of button-batteries) to very large (e.g., for batteries for wireless tools). There are also other discharge modes, such as constant-resistance discharge, content-power discharge, etc. 

Fig. 5.10 Lead-acid cell voltage discharge for a constant current discharge as a function of time...

Studies have been made of the change In voltage during constant current discharges of a 7% oxidized film at 0.1mA... 

Figure 35. Comparison of PAM, Ni-Cd and RAM AA cells on 310 mA constant current discharge to 0.75 V obtained at various temperatures.

Fig. 6.13 Temperatures in the y-z plane at locations, PI, P2, Dl, D2, D3, Cl, C2 and C3 at the holding time of 0.18 ks, and calculated isothermal contours under constant current discharge conditions, with nits in K. The values within parentheses were the temperatures measured by the thermocouples. Reproduced with permission from [33]. Copyright 2003, Elsevier...

Matsugi K, Kuramoto H, Hatayama T, Yanagisawa O (2003) Temperature distribution at steady state under constant current discharge in spark sintoing ffOcess of Ti and AI2O3 powders. J Mater Process Technol 134 225-232... 

FIGURE 2.69 Specific capacitance determined at different rates of constant current discharge between 0 and 2.5 V for cells using phosphonium-based ILs. (Reprinted with permission from Rennie, A. J. R. et al. 2013. Journal of Physical Chemistry Letters 4 2970-2974, open access.)... 

FIGURE 3.11 Ragone plots for Ru oxide (ca. 10 mg) supercapacitors with different separators. Measurements were made by constant current discharge from 1.0 V. (Liu, X. R., and R G. Pickup. 2008. Performance and low temperature behavior of hydrous ruthenium oxide supercapacitors with improved power densities. Energy and Environmental Science 1 494-500. Reproduced by permission of The Royal Society of Chemistry.)... 

Table 10.5 shows a comparison of some primary and secondary batteries, the data being obtained for R20 size (50 cm ) by constant current discharge at the 100 h rate (i.e. C/100 rate). It can be seen that while there is a wide variation of performance, the primary cells do, in general, give higher capacities and energy densities. Moreover, they are much cheaper, by at least a factor of ten. 

Figure 10.8 Constant current discharge curves for a 12 V, 100 Ah SLI lead acid battery at 25 C,...

Figure 6.10. The constant current discharging curve of the PEMFC during running with different cathode gas for 100 hours. Current density 500 mA/cm cell temperature 70 °C RH anode 65 °C, and cathode 68 °C dew points, ambient pressure [34]. (Reprinted from Journal of Power Sources, 166(1), Jing F, Hou M, Shi W, Fu J, Yu H, Ming P, et al.. The effect of ambient contamination on PEMFC performance, 172-6, 2007, with permission from Elsevier.)...

The contamination impact of SO2 was studied by Fenning et al. [10] through exposing a fuel cell to 1 ppm S02/air for 100 hours at 70°C with a constant-current discharge at 0.5 A cm. From an initial value of 0.68 V (Figure 3.1), the cell performance fell to 0.44 V, a 35% decrease. Clearly, even a trace amount of SO2 can cause a significant degradation in PEM fuel cell performance. 

Constant-current discharging curve of a PEM fuel cell during operation with 1 ppm S02/air for 100 h at 70°C. Current density 0.5 A cmA (From Fenning, J. et al. 2007.. Power Sources. 166 172-6. With permission.)... 

FIGURE 37.8 Indirect measurement constant-current discharge. 

The nominal or rated capacity of a battery is specified by its manufacturer as the standard value that characterizes this battery. Usually it is specified for a constant current discharge at 20 °C or for room temperature. For various applications, nominal or rated capacities are often referred to different discharge durations, termed as C20, Cio, or C5. 

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