Valve regulated lead-acid applications

Portable valve-regulated lead-acid cells can operate in any orientation without acid leakage and find use in many different applications, such as in electronic cash registers, alarm systems, emergency lighting unit equipment, telephone boxes, switching stations, minicomputers and terminals, electronically controlled petrol pumps, cordless television sets and portable instruments and tools. 

Refs. [i] Crompton TR (2000) Battery reference book, 3rd edn. Newnes, Oxford, pp 32/3-32/7, 51/43, 62/3-62/4 [ii] Wagner R (2004) Valve regulated lead-acid batteries for telecommunications and UPS applications. In Rand DAJ, Moseley PT, Garche /, Parker CD (eds) Valve-regulated lead-acid batteries. Elsevier, Amsterdam [iii] Broussely M (2003) Lithium-ion for EV, HEV and other industrial applications. In Nazri GA, Pistoia G (eds) Lithium batteries science and technology. Kluwer, Amsterdam, pp 671-675... 

Different types of lead-acid batteries have been developed as energy sources for many power applications, like traction and backup or standby power systems. The flooded lead-acid batteries have an excess or flooded electrolyte and they were the largest used at the beginning of the last century for many applications. Valve-regulated lead-acid (VRLA) batteries were developed as an alternative to the flooded lead-acid batteries, in order to maintain levels of distilled water and prevent drying of cells, which means safe operation for battery packs in electric... 

It remains to be seen which of the many separator materials will be successful in commercial applications. Obviously, this will depend on costs and market requirements, as well as on performance. Although most of the developments reviewed here have been directed towards EV batteries, many of the findings are equally applicable to valve-regulated lead-acid batteries intended for use in other applications. 

VALVE-REGULATED LEAD-ACID BATTERIES IN AUTOMOTIVE APPLICATIONS — A VEHICLE MANUFACTURER S PERSPECTIVE... 

Today, flooded lead acid batteries are used in SLI duty. Although installation of valve-regulated lead acid (VRLA) batteries in series-production vehicles began as early as the late 1980s [19 22], penetration of the SLI market by VRLA batteries has, so far, been quite limited. VRLA batteries are primarily used only in motorcycles, some military applications and, recently, in niche-markets such as luxury cars, taxis, and agricultural vehicles. 

VALVE-REGULATED LEAD-ACID BATTERIES FOR TELECOMMUNICATIONS AND UPS APPLICATIONS... 

Besides improvement of the utilisation of active materials (lead and lead dioxide), another crucial issue that has been in the focus of battery researchers and design engineers for many years now is the immobilisation of battery electrolyte via its absorption in the glass mat separator or by converting it into gel state. Thus, the valve-regulated lead—acid (VRLA) battery was invented which requires minimum or no maintenance and has found wide application. In the VRLAB construction, die active block in the SLI cell is higher and occupies the upper electrolyte reservoir space, thus increasing the capacity of the cell within the same volume. 

Especially important for proper operation of the battery are the impurities contained in the metal used for leady oxide manufacture. Lead for the battery industry is derived from ores mined in different parts of the world (primary lead) or is obtained by recycling of used up batteries that have reached their end of fife (secondary lead). The recycling process is very often performed at the battery manufacturers facilities. Purity standards have been adopted for the lead to be used for leady oxide production. These standards specify different maximum allowable amounts of impurities for flooded and valve-regulated lead-acid battery applications. Table 5.2 presents typical purity specifications for lead for making leady oxide for flooded batteries. 

Already today valve-regulated lead-acid batteries are in widespread use in many applications, and this trend will increase in the future since the reduction of maintenance is a signihcant advantage. This battery system requires high quality of all parameters that influence the performance and other characteristics. Valve-regulated lead-acid batteries that are installed in cabinets require sufficient air circulation to achieve equal temperature for all cells or monoblocs. Monitoring or control systems may be used. 

Since the 1970s also maintenance-free valve-regulated lead-acid batteries have been in widespread use in the field of stationary applications. Sometimes they are called recombination cells or "sealed lead-acid cells". Their correct designation, however, is in accordance to DIN 40 729 valve-regulated lead-acid batteries ( VRLA batteries). 

Valve-regulated lead-acid batteries already have displaced the vented types in many applications. 

Valve-regulated lead-acid batteries are used today in almost all applications which are applicable for conventional lead acid batteries. Since these batteries generation was basically for portable batteries, this is still a market today, for instance in the medical area. Larger types, which were developed about 20 years ago, have a wide field in military applications. Since the 1980s modern tanks and military shelters have been equipped with the 123-V 100-Ah NATO type. Its advantage besides the high deep discharge ability is the maintenance-free behavior, especially due to the limited space conditions in modern tanks. 

H Tuphorn. Valve regulated lead acid batteries systems, properties and applications. 

M.L. Soria, F. Trinidad, J.M. Lacadena, A. Sanchez and J. Valenciano, Advanced valve-regulated lead-acid batteries for hybrid vehicle applications, /. Power Sources 168,2007, 12-21. 

Lead-acid batteries were first used in stationary, stand-by applications more than 130 years ago [1]. For a long period of time, only flooded lead-acid batteries were used. Nowadays, UPS and telecommunications applications use valve-regulated batteries. Large, utility-scale applications such as load levelling continue to use flooded batteries, but it seems that, increasingly, valve-regulated batteries are chosen even for these applications. 

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