Batteries, lead-acid performance

The mathematical models of different types of batteries (lead acid [220, 221], NiMH [222], lithium-ion [223, 224]) have been developed during the last few years [219]. This has led to a better understanding of those systems. The present models consider usually, the thickness and porosity of the separators. Very little has been done in incorporating the effect of physical and chemical properties of separators on the performance and safety of batteries. This is also because the microstructure of separators and their effect on transport properties in batteries are generally known only qualitatively. 

Selenium acts as a grain refiner in lead antimony alloys (114,115). The addition of 0.02% Se to a 2.5% antimonial lead alloy yields a sound casting having a fine-grain stmcture. Battery grids produced from this alloy permit the manufacture of low maintenance and maintenance-free lead—acid batteries with an insignificant loss of electrolyte and good performance stability. 

In the 1990s, the use of batteries in electric vehicles and for load leveling is being revived partly for environmental reasons and partly because of scarce energy resources. Improvements in battery performance and life, fewer maintenance requirements, and automatic control systems are making these appHcations feasible. Research and development is ongoing all over the world to develop improved lead—acid batteries as weU as other systems to meet these needs. 

J. R. Pierson and C. E. Weinleiu, "Development of Unique Lightweight, High Performance Lead—Acid Batteries," iu J. Thompson, ed.. Power Sources 9, Academic Press, London, 1983. 

R. T. Johnson and. R. Pierson, "The Impact of Grid Composition on the Performance Attributes of Lead—Acid Batteries," iu L. J. Pearce, ed.. Power Sources 11, International Power Sources Symposium Committee, 1987. 

The Na—S battery couple is a strong candidate for appHcations ia both EVs and aerospace. Projected performance for a sodium—sulfur-powered EV van is shown ia Table 4 for batteries having three different energies (68). The advantages gained from usiag a Na—S system rather than the conventional sealed lead—acid batteries are evident. 

The history of the lead-acid battery goes back to 1854 when Sinsteden published performance data on this battery system for the first time (cf. Ref., [1]). The practical... 

Since grid material is converted into lead dioxide, a slight increase in the actual capacity is often observed with lead-acid batteries. The reduced cross-section in Fig. 9 does not affect the performance of batteries that are used for discharge durations in the order of one hour or more. Attention must, however, be paid to batteries that are loaded with high currents, because the conductivity of the grid gains importance with increased current flow. 

The thermodynamic properties of magnesium make it a natural choice for use as an anode material in rechargeable batteries, as it may provide a considerably higher energy density than the commonly used lead-acid and nickel-cadmium systems, while in contrast to Pb and Cd, magnesium is inexpensive, environmentally friendly, and safe to handle. However, the development of Mg-ion batteries has so far been limited by the kinetics of Mg " " diffusion and the lack of suitable electrolytes. Actually, in spite of an expected general similarity between the processes of Li and Mg ion insertion into inorganic host materials, most of the compounds that exhibit fast and reversible Li ion insertion perform very poorly in Mg " ions. Hence, there... 

Spent lead-acid battery reclamation Persons who generate, transport, regenerate, collect, and store spent lead-acid batteries prior to reclamation, but do not perform the actual reclamation, are not subject to hazardous waste regulation. U.S. EPA established those provisions to encourage the recycling of these batteries. However, owners and... 

New battery systems could give better performance but they have not been forthcoming. Performance is limited by the lead-acid battery packs which are generally the most affordable option. More unfamiliar batteries like nickel metal hybride (NiMH) packs have also appeared. 

Cost The cost of the battery is determined by the materials used in its fabrication and the manufacturing process. The manufacturer must be able to make a profit on the sale to the customer. The selling price must be in keeping with its perceived value (tradeoff of the ability of the user to pay the price and the performance of the battery). Alkaline primary Zn—MnOz is perceived to be the best value in the United States. However, in Europe and Japan the zinc chloride battery still has a significant market share. In developing countries, the lower cost Leclanche carbon—zinc is preferred. Likewise, lead acid batteries are preferred for automobile SLI over Ni—Cd with superior low-temperature performance but with a 10 times higher cost. 

Very little work (relative to research of electrode materials and electrolytes) is directed toward characterizing and developing new separators. Similarly, not much attention has been given to separators in publications reviewing batteries.A number of reviews on the on cell fabrication, their performance, and application in real life have appeared in recent years, but none have discussed separators in detail. Recently a few reviews have been published in both English and Japanese which discuss different types of separators for various batteries. A detailed review of lead-acid and lithium-ion (li-ion) battery separators was published by Boehnstedt and Spot-nitz, respectively, in the Handbook of Battery Materials. Earlier Kinoshita et al. had done a survey of different types of membranes/separators used in different electrochemical systems, including batteries."... 

The most important use of barium is as a scavenger in electronic tubes. The metal, often in powder form or as an alloy with aluminum, is employed to remove the last traces of gases from vacuum and television picture tubes. Alloys of barium have numerous applications. It is incorporated to lead alloy grids of acid batteries for better performance and added to molten steel and metals in deoxidizing alloys to lower the oxygen content. Thin films of barium are used as lubricant suitable at high temperatures on the rotors of anodes in vacuum X-ray tubes and on alloys used for spark plugs. A few radioactive isotopes of this element find applications in nuclear reactions and spectrometry. 

Nickel-cadmium batteries with thin sintered plates are used for on-board power supplies in aircraft, helicopters, tanks and military vehicles where their excellent low temperature, high rate performance is an important attribute. Modern 40 Ah cells designed for airborne use can deliver 20 kW of instantaneous power at 25°C and over 10 kW at —30DC. Again, the high cost of this system compared with that of lead-acid batteries has restricted its use. 

Figures 30 and 31 refer to the excellent performance of this battery type (see Figure 31, high cell voltage of 3 V, ten times better mass-related energy content than for the lead-acid accumulator) such cells have not been commercialized up to now. This is not because of the problems to maintain the temperature—this is achieved by the waste heat—it is because the danger of crack formation and resulting catastrophic local chemical reactions that led to the fact that investigations with respect to electrotraction have been essentially abandoned.

Strong contenders for automotive power are the sodium/sulphur and sodium/ nickel chloride batteries, the latter known as the ZEBRA cell. ZEBRA was originally (c. 1979) an acronym devised for commercial security reasons but now it stands for the very apt Zero Emissions Batteries Research Activity . Several European car manufacturers including BMW and Mercedes have incorporated the ZEBRA cell into prototype cars, vans and buses. The performance of the battery far outstrips that of the lead/acid counterpart, as is evident from Fig. 

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