One type of anode used in electrowinning has been lead based anode, which could have a negative effect on the quality of copper deposited
One significant disadvantage of using such lead based anodes is that during electrowinning operations small amounts of lead are released from the surface of the anode, which causes the undesirable particulates to be suspended in the electrolyte. In addition, the lead sludge must be cleaned periodically from the cell bottom e.g. every 45 to 90 days, and during this time the electrowinning cell is not producing metal.