Lifetime cycles

Cycle life is another important factor because it determines the longevity of the battery in practical use. The number of lifetime cycles depends strongly on the so-called depth of discharge if only some 10-20% of the full discharge capacity is used (as in the Toyota Prius for instance) the batteries can handle millions of shallow cycles . However, for PHEVs or BEVs the number of deep cycles (typically 80% discharge) is a relevant characteristic. 

From the lifetime cycle of a MSWI plant of about 30-40 years it is obvious that at least in the next two decades conventional MSWI BA will remain the dominant residue. In some European countries (e.g., The Netherlands, Germany, or France) legislation allows MSW BA to be used as secondary raw material, mainly for road construction. Some investigations proposed the use of MSW BA in concrete or other cementitious products (e.g., Targan et al. 2002) or as sintering promoters in porcelainized stoneware (Barbieri et al. 2002). 

Dudek, M., L. Wolska, H. Walk, A. Stachowiak-Wencek, and J. Namiesnik. 2004. Studies on evaluation of the ship lifetime cycle. Ecol. Tech. 15 141-153. 

In Denmark, the Environmental Protection Act , adopted in 1993, requires producers and importers to increase both lifetime cycle and recycling of their products and to assure that their dumping does not involve any damage to the environment. Users and consumers are expected to contribute disposal problems and promote recycling. 

Chip size, mm Average lifetime, cycles TempDepend model ViscoElast model ... 

Design optimization and lifetime cycle assessment of adhesively bonded joints... 

Figure C 1.5.10. Nonnalized fluorescence intensity correlation function for a single terrylene molecule in p-terjDhenyl at 2 K. The solid line is tire tlieoretical curve. Regions of deviation from tire long-time value of unity due to photon antibunching (the finite lifetime of tire excited singlet state), Rabi oscillations (absorjDtion-stimulated emission cycles driven by tire laser field) and photon bunching (dark periods caused by intersystem crossing to tire triplet state) are indicated. Reproduced witli pennission from Plakhotnik et al [66], adapted from [118].

Fatigue. Engineering components often experience repeated cycles of load or deflection during their service fives. Under repetitive loading most metallic materials fracture at stresses well below their ultimate tensile strengths, by a process known as fatigue. The actual lifetime of the part depends on service conditions, eg, magnitude of stress or strain, temperature, environment, surface condition of the part, as well as on the microstmcture. 

Economic Factors These inchrde capital cost (eqrripment, installation, engineering, etc.), operating cost (rrtUities, maintenance, etc.), emissions fees, and life-cycle cost over the expected eqrripment lifetime. 

Here is the number of cycles to fracture under the stress cycle in region i, and Nj/Nf is the fraction of the lifetime used up after N, cycles in that region. Failure occurs when the sum of the fractions is unity (eqn. (15.4)). This rule, too, is an empirical one. It is widely used in design against fatigue failure but if the component is a critical one. Miner s Rule should be checked by tests simulating service conditions. 

The life cycle cost of a process is the net total of all expenses incurred over the entire lifetime of a process. The choice of process chemistry can dramatically affect this life cycle cost. A quantitative life cycle cost cannot be estimated with sufficient accuracy to be of practical value. There is benefit, however, in making a qualitative estimate of the life cycle costs of competing chemistries. Implicit in any estimate of life cycle cost is the estimate of risk. One alternative may seem more attractive than another until the risks associated with product liability issues, environmental concerns, and process hazards are given due consideration. Value of life concepts and cost-benefit analyses (CCPS, 1995a, pp. 23-27 and Chapter 8) are useful in predicting and comparing the life cycle costs of alternatives. 

Life-cycle analysis (LCA) does not account for economic aspects, and such analysis should therefore be considered together with a life-cycle cost analysis (LCC), which takes into account the costs of investment, energy, maintenance, and dumping the final waste product throughout the lifetime of a plant. 

Another important parameter for describing a secondary electrochemical cell is the achievable number of cycles or the lifetime. For economic and ecological reasons, systems with a high cycle life are preferred. The number of cycles indicates how often a secondary battery can be charged and discharged repeatedly before a lower limit (defined as a failure) of the capacity is reached. This value is often set at 80 percent of the nominal capacity. To compare different battery systems, besides the number of cycles, the depth of discharge must be quoted. 

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