The present disclosure relates to systems and methods by which lead from spent lead-acid batteries may be extracted, purified, and used in the production of new lead-acid batteries. The system includes a first phase separation device configured to: receive the first mixture from the basic lead stream digestion device, isolate a liquid component from one or more insoluble components of the first mixture, and output the liquid component. The system also includes a lead salt precipitation device configured to: receive and mix the liquid component and a carboxylate source to form a second mixture including a lead salt precipitate, and output the second mixture. The system further includes a second phase separation device configured to: receive the second mixture from the lead salt precipitation device, isolate the liquid component from the lead salt precipitate of the second mixture, and output the lead salt precipitate.