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Its sales represent approximately 40 to 45% of the sales value of all batteries in the world, or a market value, in 1999, of about $15 billion at manufacturers' levels and 2 to 3 times this value at retail levels. (These values do not include some countries such as Russia and China, for which complete market data are not available.)

This battery system is also used extensively in telephone systems, power tools, communication devices, emergency lighting systems, and as the power source for mining and material-handling equipment. The wide use of the lead-acid battery in many designs, sizes, and system voltages is accounted for by the low price and the ease of manufacture on a local geographic basis of this battery system. The lead-acid battery is almost always the least expensive storage battery for any application, while still providing good performance and life characteristics.New uses, designs, and fabrication processes are still being introduced at significant rates.

Some of the new designs are for modern electric-vehicle, energy-storage, and electronics applications.There have been many improvements in lead-acid battery design and charger system logic to make high-voltage batteries more uniform in performance. Electric-vehicle batteries are typically 100 to 300 V systems. The lead-acid battery has a high electrical turnaround efficiency, 75 to 80%, which makes the system attractive for electric-vehicle and energy-storage use. Traditional vertical-plate batteries are capable of energy densities greater than 40 Wh/kg, and a horizontal-plate design with higher energy and power densities have found use in traction and fork lift applications.Modified lead-acid batteries are being investigated for both electric and hybrid-drive vehicles.

The world's largest energy-storage battery system was finished in late 1988. This 40-MWh battery, located in Chino, Calif., uses individual industrial-size lead-acid cells in series and parallel connection to make a l0-MW system delivering energy into the utility grid at 2000 V and 8000 A for 4 hours. AC to DC conversion is built into the system. This battery operated for more than a decade as a demonstration project. At the other extreme, small individual lead-acid cells and batteries are now available with quick connects for use in small electric appliances and electronics applications. Many of these newer applications require low-maintenance or maintenance-free designs. Thin film capacitor-like lead-acid batteries have become commercially available in the past few years, for consumer and electronic applications. Some larger industrial cells are often virtually maintenance-free using the oxygen-recombination principle and a reseal able Bunsen vent. An approach to high energy density, high-power-density, high-cycle-life lead-acid battery design is the bipolar design, a design which is still being pursued. The problems which prevent this design from larger scale commercial use relate to the availability of a bipolar material which is electronically conductive, nonporous to ions, low cost, and stable against both positive and negative active materials. Conductive plastics, which are used in some battery systems, have not been successful in lead batteries. Experiments have been carried out with a bipole made from tinoxide coated glass encapsulated in a plastic matrix, and with multilayers of different lead alloys to slow the penetration of the bipole by corrosion.

Major Advantages and Disadvantages of Lead-Acid Batteries

Advantages

Disavnatages

Popular low-cost secondary battery-capable of manufacture on a local basis, worldwide, from low to high rates of production	Relatively low cycle life (50-500 cycles*)
Available in large quantities and in a variety of sizes and designs-manufactured in sizes from smaller than I Ah to several thousand Ampere-hours	Limited energy density-typically 30-40 Wh/kg
Good high-rate performance-suitable for engine starting (but outperformed by some nickel-cadmium and nickel metal-hydride batteries)	Long-term storage in a discharged conditions can lead to irreversible polarization of electrodes (sulfation)
Moderately good low- and high-temperature Performance	Difficult to manufacture in very small sizes (It is easier to make nickel-cadmium button cells in the smaller than 500-mAh size)
Electrically efficient-turnaround efficiency of over 70%, comparing discharge energy out with charge energy in	Hydrogen evolution in some designs can be an explosion hazard (flame arrestors are installed to prevent this hazard)
High cell voltage-open-circuit voltage of > 2.0 V is the highest of all queouselectrolyte battery systems	Stibene and arsine evolution in designs with antimony and arsenic in grid alloys can be a health hazard
Good float service Easy state-of-charge indication Good charge retention for intermittent charge applications (If grids are made with highovervoltage alloys)	Thermal runaway in improperly designated batteries or charging equipment.
Available in maintenance-free designs	Positive post blister corrosion with some designs.
Low cost compared with other secondary Batteries
Cell components are easily recycled.

*Up to 2000 cycles can be attained with special designs.

source:

needbattery.com