Discharging capacity measurement

Electrochemical cell with quartz window and saturated calomel electrode as a reference electrode was used (Fig. 3). Photoelectrochemical measurements were conducted with Pl-50-1 potentiostat under illumination power density of 75 mW/cm. At first the efficiency of energy accumulation (in the form of absorbed hydrogen) was estimated from the cathode discharge curves and from the hydrogen volume released under cathode heating. The volume of hydrogen released was measured in the tailor-made setup. The discharge capacity measurements were performed in electrochemical cell with nickel counter electrode. 

Discharge capacities were measured at 4.0 V at a constant current of 5.0 mA. 

PPy [19]) up to 500 cycles. However, when continuing the measurement, discharge capacity of both batteries gradually decreased. Especially, in Figure 5b on the PAN system, the capacity became nearly 0 after 4000 cycles were completed, and it could not be operated beyond 4000 cycles. On the contrary, the PMMA system showed no sudden decrease and more than 8000 cycles were obtained (Figure 5a). 

Table I. Capacities Measured between Electrodes of Discharge Tube...

The EPR harmonization process led to another concept considering the reactor scram as a pressure reducing measure, which allows to reduce the overall discharge capacity, provided the reliability and diversity of the provisions related to the reactor scram are similar to those of the protection of the core. 

Fig. 22.5 Discharge capacity of Carbotron P (J) measured at various current density. The highest current density corresponds to 60 C...

The discharge capacity of the trap depends on the flow area of the valve orifice, the pressure drop across it, and the inlet temperature of the condensate. There is a considerable problem in measuring the pressure drop because hot condensate flashes as it passes through the valve orifice. Trap capacity is not truly defined by orifice size and pressure differential. Pressures upstream and downstream of the trap are also subject to variation, depending on calandria performance, flowrates, temperatures, and system back pressure. The orifice may never be fully open to flow because of the valve design. Nor can flow coefficients be measured with the same precision as for control valves, since the valve stem in the trap is often not definitely located with reference to the orifice. 

The battery capacity decreases with age and cycling. Therefore, the reference value of nominal capacity also needs a periodical calibration. The easiest way is to perform a full charge and discharge cycle at low current rate (reference cycle). Based on this cycle, a discharge capacity is measured and a maximum capacity value is updated. 

Capacity measuring conditions Charging 0 1CX16Hrs. Discharge 0 2C, E V.=0.W. Temperature 20 C... 

Battery life is specified as calendar and cycle life. Factors that limit the life are corrosion, resistance rise, and capacity loss [5]. Without electrochemical operation, cell slowly degrades, but the calendar life of 11 years is demonstrated [1]. The cycle life is measured by the accumulation of all discharged charge measured in Ah divided by the nominal capacity in Ah. Each cycle for nominal capacity is equivalent to a 100 % discharge cycle. The expected cycle life is up to 3,500 cycles [1] from module tests and 1,450 cycles from battery testing [1] that simulated all real-life operation conditions. The thermal insulation was stable for more than 15 years in the report of C. H. Dustmann [1]. 

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