While they may seem like a small piece of the recycling puzzle, batteries constitute a huge potential area of impact, especially as it relates to rechargeables. They contain heavy metals that could be dangerous if they end up in landfills (and our environment), and they have widespread recycling options.
Lead Acid Batteries are broken apart into plastic, lead, and sulfuric acid particles where they are then processed and reused if possible.
Nickel-Cadmium, Nickel Metal Hydride, and Lithium Ion Batteries are broken down into high temperature and low temperature metals. High temperature metals are re-heated to molten temperatures and then solidified into casts. Low temperature metals separate during the melting operation and are collected as metal-oxides.
Lithium Batteries are broken down into their contents. They are then submerged in caustic (basic not acidic) water. This solution neutralizes the metals and the scrap is then recycled. The solution is then filtered where carbon is recovered and pressed into sheets of carbon cake. The lithium is converted to a white powder which can be reused in new batteries.
Mercury Batteries and heavy metals are recovered through a controlled temperature process. This is a type of battery which is slowly being phased out.