Sealed lead-acid battery

Lead-acid batteries have been in use for various applications over the past two centuries. These batteries are most cost-effective, can be recharged multiple times, and have been widely deployed in automobiles and trucks and as emergency power sources. These batteries are relatively heavy and take longer times for recharging. 

In some applications, it is necessary to use sealed lead-acid batteries (SLABs), for which safety, reliability, and long service life are important design considerations. These cells are produced in various sizes and shapes and have capacities in the range of 1 to 2 Ah. These SLABs offer more than 200 cycles of life at discharge times as short as an hour. Such batteries with larger sizes are available for notebook computers or minicomputers. SLABs offer the following benefits  

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Wrought or extmded lead—teUurium (0.035—0.10 wt %) aUoys produce extremely fine grains. The binary aUoy is, however, susceptible to recrysta11i2ation. The addition of copper or sUver reduces grain growth and retains the fine grain si2e. Because teUurium is a poison for sealed lead—acid batteries, the teUurium content of lead and lead aUoys used for such purposes is usuaUy restricted to less than 1 ppm. 

The case is the largest portion of the container. The case is divided into compartments which hold the cell elements. The cores normally have a mud-rest area used to collect shed soHds from the battery plates and supply support to the element. Typical materials of constmction for the battery container are polypropylene, polycarbonate, SAN, ABS, and to a much lesser extent, hard mbber. The material used in fabrication depends on the battery s appHcation. Typical material selections include a polypropylene—ethylene copolymer for SLI batteries polystyrene for stationary batteries polycarbonate for large, single ceU standby power batteries and ABS for certain sealed lead—acid batteries. 

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. 

Power source Wall plug in AC 2 X 9-volt alkaline battery NiCd rechargeable battery pack Wall plug in AC one 8-volt sealed lead-acid battery 2 X 9-volt alkaline or lithium batteries external lead-acid battery pack Four D-cell alkaline batteries AC power kit with two rechargeable NiCd batteries... 

Refs. [i] HammelRO, Salkind AJ, Linden D (1994) Sealed lead-acid batteries. In Linden D (ed) Handbook of batteries, 2nd edn. McGraw-Hill, New York, pp 25.29-25.30 [ii] Nagy Z (ed) (2005) Online electrochemistry dictionary, http //electrochem.cwru.edu/ed/dict.htm [Hi] Crompton TR (2000) Battery reference book, 3rd edn. Newnes, Oxford, Chap. 31.14, pp 31.18-31.19... 

Some units have optional internal batteries, and can operate without them, and are solely used for charging an external battery bank. These different configurations will be noted in the operator s manual. Most units use sealed lead acid batteries that require chargers specifically designed for sealed batteries. 

For small-size portable rechargeable batteries, the collection of spent nickel cadmium batteries started in 1985 and has been pursued in combination with the collection of nickel metalhydride batteries, lithium ion batteries and small-size sealed lead-acid batteries. The collection rate of nickel cadmium batteries was over 40% in 2000. 

Approximately 80% of all small-size sealed lead-acid batteries are estimated to be used for commercial purposes, such as UPS, and should be treated in the same way as industrial batteries, as stated above. 

Sealed lead-acid batteries are in both cylindrical and prismatic shapes. The cyclindrical ones (usually designed as SLA batteries) have excellent high-rate characteristics. Other than in portable devices, sealed batteries can be used in standby applications, e.g. telephone exchange stations, were they are kept in float charge. In this case too, oxygen recombination is possible. 

An Act To phase out the use of mercury in batteries and provide for the efficient and cost-effective collection and recycling or proper disposal of used nickel cadmium batteries, small sealed lead-acid batteries, and certain other batteries, and for other purposes. 

Rhode Island law prohibits the disposal of Ni-Cd, mercuric-oxide, and small sealed lead-acid batteries in municipal or commercial solid waste. Manufacturers of these battery types must ensure that a system exists for the proper collection, transportation, and processing of waste batteries (this requirement pertains only to manufacturers whose batteries are used by a government agency or an industrial, communications, or medical facility). Manufacturers must accept waste batteries returned to their facilities for proper processing. 

In 1957, Otto Jache from Sonnenschein introduced the gel electrolyte and patented the sealed lead—acid battery [18]. In this battery construction, the oxygen evolved at the positive plates passes through cracks in the gel and reaches the negative plates, where it is reduced and thus restores the lost water and suppresses hydrogen evolution. The German company Sonnenschein started mass production of gel-sealed lead—acid stationary batteries. 

Dietz, H. Radwan, M. Doering, H. Wiesener, K. On the hydrogen balance in sealed lead/acid batteries and its effect on battery performance. J. Power Sources 1993,42, 89-101. 

The desire for maintenance-free service, e.g., in decentralized single emergency lights for panic lighting, around 1960 had led to the development of small, sealed, lead-acid batteries with gelled electrolyte [20, 21]. An idea that was already known — the gelling of electrolyte — became applicable to the sulfuric acid electrolyte with the industrial availability of silica types of very high surface area. These fumed silicas have an internal surface of, say, 200-300 g" and convert sulfuric... 

Another commonly used chemistry is the sealed lead-acid battery. The flooded version is found in automobiles, but most portable equipment use the sealed version, also referred to as gelcell or SLA. 

Hariprakash, B., Bera, R, Martha, S.K., Gaffoor, S.A., Hegde, M.S., Shukla, A.K. Ceria supported platinum as hydrogen-oxygen recombination catalyst for sealed lead-acid batteries. Electrochem. Solid-State Lett. 4, A23-A26 (2001)... 

The principle is well known from sealed lead acid batteries, which contain their electrolyte immobilized, by glass mats or silica gel. For lithium rechargeable batteries it is called SPE (solid polymer electrolyte) or gel technology. 

Sealed lead-acid battery 6.0 0.166 Widely used for ICE-based cars... 

Table 7.1 Typical Characteristics of Sealed Lead-Acid Batteries with a 6 V Output Voltage...

Caven, W., Horizon Sealed Lead-Acid Battery in Electric Vehicle Application, in Annual Battery Conf. on Applications nnd Advances. IEEE. Long Beach, CA, January 9-12, 1996, pp. 159-162. 

Chreitzberg, A., and Chiaccho, F., Method of Making a Sealed Lead-Acid Battery with a Gel Electrolyte and Sealed Lead-Acid Storage Battery Made Aceording to This Method, U.S. Patent 4,687,718, 1987. 

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