Batteries types

Fig. 13. Effect of temperature on discharge efficiency (a) at 270 mA-h of miniature 2inc—mercuric oxide batteries type EP675E, and (b) at 175 mA-h of...

Batteries, both primary and secondary, have become very big business indeed, which moreover is growing rapidly. Salkind (1998) in a concise overview of the entire domain of battery types and technologies, estimates that in 1996, the world market in the two types of battery combined totalled ss 33 billion dollars, and that the ratio of secondary to primary battery sales is steadily edging upwards. In spite of its poor charge density per unit mass, the lead-acid battery still accounts for more than a quarter of the total, because it costs so much less than its rivals and lasts well. 

Battery types are either lead-acid or nickel-cadmium cells. Lead-acid types have been used for a long time and, when correctly maintained, have a working life of 25 years. Nickel-cadmium batteries offer the same working life as lead-acid but are smaller in weight and volume, generally with a higher initial capital cost. Loads applied to D.C. systems can be categorized into three types ... 

Marketing forecasts for batteries have been compiled from the Annual Reports published by several battery companies. Information based on the trade journals and investor s brochures, which surveyed and evaluated the present and future global distribution of battery types, was collected. Points of interest were the availability of batteries and their performance/cost ratios, but also geographical usage in connection with social considerations, such as per-... 

The most important driving forces for the motion of ionic defects and electrons in solids are the migration in an electric field and the diffusion under the influence of a chemical potential gradient. Other forces, such as magnetic fields and temperature gradients, are commonly much less important in battery-type applications. It is assumed that the fluxes under the influence of an electric field and a concentration gradient are linearly superimposed, which... 

Some further important aspects for the design of solid electrolytes and solid electrodes for battery-type applications are the following ... 

FIGURE 19.3 Typical discharge curves for various battery types. 

Widely used parameters are the specific energy or power per unit mass (w = W/M, in Wh/kg, orp = P/M, in W/kg). In each battery type the specific energy is a falling function of specific power. Plots of w vs. p (Ragone, 1968) yield a clear illustration of the electrical performance parameters of given types of batteries and are very convenient for their comparison (see Fig. 19.4). 

Battery characteristics depend strongly on the operating temperature. As a rule, both the discharge voltage and the reactant utilization coefficient are lower at lower temperatures. On the other hand, increased temperatures are conducive to side reactions (such as corrosion processes) and thus reduce battery efficiency. Therefore, each battery type is designed for a specific temperature range within which its characteristics will be within the prescribed limits. 

The numerous existing battery types vary in their size, stractural features, and nature of the chemical reactions. They vary accordingly in their performance and parameters. This variety reflects the diverse conditions nnder which cells operate, each field of application imposing its specific reqnirements. 

Subcategory Anode Materials Cathode Materials Battery Type Examples... 

Nominal Voltage and Storage Density of Various Battery Types... 

Battery Type Nominal Voltage (V) Storage Density (wh/kg)... 

These batteries are much cheaper to make than earlier nickel battery types, and have an energy density almost double that of lead-acid. NiMH batteries can accept three times as many charge cycles as lead-acid, and work better in cold weather. NiMH batteries have proven effective in laptop computers, cellular phones, and video cameras. 

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