Rate capability

Viscometer Price a range Viscosity range, mPa-s (= cP) Shear rate capability. Temperature control Manufacturer... 

Relatively large gas flow rates capable of effective handling... 

When an extraction-condensing turbine is decided upon, it may be specified in three different ways, depending upon process steam and power demand. Referring to Fig. 29-24, the usualpurchase is a unit in which rated capability can be carried either straight-... 

If the process-steam demand is high and steac, then the exhaust size can be reduced, because not much condensing capacity is required. The choice would be to save cost by a smaller exhaust which would terminate the zero-extraction hne at C, while the total-extraction line would extend to B for rated capability. 

The filter elements should remove particles of five microns, must be water-resistant, have a high flow rate capability with low pressure drop, possess high dirt-retention capacity, and be rupture-resistant. The clean pressure drop should not exceed five psig at 100 °F (38 °C). The elements must have a minimum collapse differential pressure of 50 psig. Pleated-paper elements are preferred—provided they meet these requirements. Usually, the pleated-paper element will yield the five psig clean drop when used in a filter that was sized to use depth-type elements. This result is due to the greater surface area of the pleated element, more than twice the area of a conventional stacked disc-type or other depth-type elements. 

I here is little capacity loss upon cycling, and the materials show adequate rate capability. 

The physicochemical properties of carbon are highly dependent on its surface structure and chemical composition [66—68], The type and content of surface species, particle shape and size, pore-size distribution, BET surface area and pore-opening are of critical importance in the use of carbons as anode material. These properties have a major influence on (9IR, reversible capacity <2R, and the rate capability and safety of the battery. The surface chemical composition depends on the raw materials (carbon precursors), the production process, and the history of the carbon. Surface groups containing H, O, S, N, P, halogens, and other elements have been identified on carbon blacks [66, 67]. There is also ash on the surface of carbon and this typically contains Ca, Si, Fe, Al, and V. Ash and acidic oxides enhance the adsorption of the more polar compounds and electrolytes [66]. 

Gozdz et al. (of Bellcore) [25] recognized that poly (vinylidene difluoride) hexafluoropropylene (PVDF HFP) copolymers could form gels with organic solvents and developed an entire battery based on this concept. Typically, the gel separator is 50 pm thick and comprises 60wt. % polymer. In the Bellcore process the separator is laminated to the electrodes under pressure at elevated temperature. The use of the PVDF HFP gelling agent increases the resistivity of the electrolyte by about five times which limits the rate capability of such batteries. 

Porous zinc electrodes with highly developed surface are elaborated in this laboratory, which show extremely high discharge rate capability in wide temperature range (down to -40°C). The self-discharge of the zinc is well suppressed without the use of any unacceptable mercury and a high amper-hour capacity of these zinc electrodes is achieved. 

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. 

LBG1025 (discussed in the previous sections of this paper), the electrochemical performance of SLA1020 is slightly lower in terms of material s rate capability. This becomes noticeable at C/2 and C rates. From what we have reported previously, the electrochemical behavior should be considered as only one of several critical parameters. 

At the electrochemical performance level, these novel natural graphite-based materials surpass mesophase carbon s characteristics as related to cell/battery safety performance, low irreversible capacity loss, and good rate capability even at high current densities. 

To verify the rate capability of the SLC-1015 material, cell with lithium counter electrodes were cycled at the C/10 and C/2 rates, respectively, as shown in Figure 4. The practical discharge capacities for the... 

The cycling improvement for the Cu-metallized graphite over the pristine graphite was also observed by K. Guo et al. [15] in their study of electroless Cu deposited on graphite cycled in a lithium cell with a 20% PC blend electrolyte. Also, they recorded a rate capability improvement in their Cu graphite material as well. At a current density of 1.4 mA/cm2, the cell achieved about 60% ( 200 mAh/g) of the charge capacity measured at 0.14 mA/cm2, compared to about 30% ( 100 mAh/g) for the non-treated pristine natural graphite cell [15]. 

At 50°C, a marked improvement was seen over the baseline cell, both in terms of more stable cycling, a higher rate capability, and less first cycle irreversible capacity loss. Reasons for the improvement in performance appear to be related to a lowering of the electrode material impedance and a smaller first cycle irreversible capacity by suppression of PC solvent cointercalation due to a de-solvation catalyzed by Cu metal. 

The lithium-storage properties of these Si SiOx/C nanocomposite electrodes were investigated in different electrolyte systems and compared to pure Si nanoparticles. From all the analyzed systems, the Si SiOx-C nanocomposite in conjunction with the solvent vinylene carbonate (VC) to form the solid-electrolyte interface showed the best lithium storage performance in terms of a highly reversible lithium-storage capacity (1100 mAh g-1), excellent cycling performance, and high rate capability (Fig. 7.9). 

Fig. 11.4 (a) Cross-section SEM observation of the VACNT/GPfilm (b) cyclic performance and high-rate capability of the VACNT/GP film anode of an LIB (reprinted with permission from Shisheng Li,ef at., Adv. Energy Mater. 2011,1, 486-490). 

ECs are another promising electrical energy storage device with a higher energy density than electrical capacitors, and a better rate capability and cycling stability than LIBs [32]. Carbon-based electric double layer capacitors and metal oxide- or polymer-based pseudocapacitors are two main types of ECs. The charge-... 

ZnO [79] have been used in ECs. These hybrids all show enhanced electrochemical performance in terms of the high reversible capacity of LIBs or specific capacitance of ECs, rate capability, and cycling performance. 

Given the importance of particle size to rate capabilities in Li+ batteries, preparation of nanostructures of Li+ insertion material for possible use as electrodes in Li+ batteries seemed like an obvious extension of our work on nanomaterials. The fact that these nanostructures can be prepared as high-density ensembles that protrude from a surface like the bristles of a brush (Fig, 2A) seemed particularly useful for this proposed application because the substrate surface could then act as a current collector for the nanostructured battery electrode material. 

It is imperative that the processor utilize every advantage available to ensure success since the specification of equipment in an extrusion line also affects resin usage and labor. Thus, it is always more cost effective in the long run to design and install an extrusion line that (1) has a maximum rate capability of at least 25% more than the expected maximum rate, and (2) has a properly engineered line (that might have a higher capital cost) to achieve maximum profitability. 

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