Lead-acid batteries recycling technologies

NEW CLEAN TECHNOLOGIES TO IMPROVE LEAD-ACID BATTERY RECYCLING... 

Frias, C, Garcia, M and Diaz, G, 2000. New clean technologies to improve lead acid battery recycling, in Proceedings Lead-Zinc 2000, pp 791-801 (The Minerals, Metals and Materials Society (TMS) Littleton). 

This chapter provides a review of life-cycle issues that are likely to be important for lead-acid battery production and recycling. Issues specific to VRLA technology are noted, as are generic considerations associated with other lead-acid battery... 

Lead-acid batteries received a high score by virtue of being a commercial product with an established recycling infrastructure. Nickel/metal hydride and nickel/cadmium are also widely available commercially and are routinely recycled. Zinc batteries are sold in large quantities and little or no hazardous waste and pollutants are produced by processing. Most of the battery technologies farther down the list are ranked lower because the batteries are not commercial products and recycling processes are not developed any further than a bench scale. In the case of sodium/sulflir batteries, the market outlook for recovered products is unfavorable. 

Over 95% of failed lead—acid batteries are recycled in these pools, yielding secondary lead which is re-used for the manufacture of new lead—acid batteries. The secondary lead is purified to a degree, allowing its utilization in the production of leady oxide and lead alloys. A certain amount of primary lead extracted from lead ores is also added to the lead pool and used in the manufacture of leady oxide. Thanks to the high percentage of recycled secondary lead and the simple technology of manufacture, the lead—acid battery is the cheapest chemical power source available. 

In contrast to most other uses, lead-acid storage batteries have largely maintained, if not extended, their market position and range of applications in recent years. For the SLI market, especially, the lead-acid battery technology has several advantages over other alternative systems, in terms of both cost and performance (where lead s specific electrical and chemical properties are a crucial factor). The main influences here, as we have seen, have been technical changes which have improved battery performance, but economised on lead usage per battery. A further barrier to the introduction of any new, alternative SLI battery technolc is the widespread and weU-estab-lished infrastructure that already exists to produce and recycle lead-acid batteries. 

Another conventional battery technology that has been considered for EVs is Ni/Cd. Although capable of somewhat better performance than lead-acid in some respects, this battery is also more costly and does not equal the performance levels possible with advanced battery systems. It is unlikely to see widespread use in EV applications in the U.S. although there are reported to be more than 10,000 EVs using Ni/Cd batteries presently on the road in Europe [23]. Because of the toxicity of cadmium, which precludes disposal, and the value of the nickel, there are well-developed processes for recycling of Ni/Cd batteries. Most of the facilities in Europe are dedicated Ni/Cd battery recycling plants. 

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