Lead Battery Recycling in Bangladesh

1 Introduction and Background

More than 765.000 SHS have been installed in Bangladesh up to end of 2010. It is planned to extent the program to some 2.5 Mio SHS within the next 5 years. All SHS consist of a solar PV module, charge controller and a battery. While solar panels have a warranty time of 20 yrs and more, the typical lead batteries have a warranty of 5 years and a typical life time of 7-8 years. Today used lead batteries are still mostly coming from cars, telecom and other applications but during the next years some 600.000 used solar batteries will be disposed calling for proper recycling.

Recycling of batteries means (1) to collect the used batteries and (2) to bring them to recycling plants where the lead and in particular the lead-oxides are recycled to pure lead for further use as raw material again. There are already a number of recycling initiatives and plants, from the very basic open-air recycling on charcoal to the more sophisticated plants using rotating furnaces. The principle is to melt the lead structures of the battery and to reduce the lead oxides at high temperature (>850 °C) to molecular lead. The challenges of the recycling processes are manifold, including:

(1) increase of recycling efficiency and purity of the lead,

(2) reduction of any harm to the health of the workers (continues exposure is very poisoning),

(3) reduction of the environmental impact to the air, soil and water,

(4) proper disposal of any residues containing sulphur compounds and traces of heavy metals.

Lead battery recycling plants so far are mostly recycling batteries with flat plates. Solar home sys¬tems batteries are in some details different as they have tubular plates inside but in principal they are similar and can be recycled in same plants with some differences in dismantling.

KfW and other donors (e.g. World Bank) of SHS programs are concerned about proper recycling of batteries in the SHS programs after the lifetime is reached. This is an issue to be taken up already now as there will be a predictable need for more and better recycling capa-cities in the next years and these capacities need to be provided now. This report aims at contributing to this discussion by pre¬senting results of the visits at selected recycling plants and discussions with Bangladesh experts to get a better idea on the current technological status and needs for improvements and possibilities for support through KfW and partner IFIs.

Assuming (i) 2 Mio SHS installed in some years with a battery life time of 7 years, and (ii) roughly 1 Mio cars in use in Bangladesh (for 2010 it is close to 0.9 Mio) with a battery life time of 3.5 years, then some 571,000 lead batteries need to be recycled per year. A standard battery (55-60