Alkaline batteries are everywhere. They are the most common household battery and are used in many low power applications: remote controls, alarm clocks, toys and torches to name a few. Alkaline batteries are primary, or single use, batteries and so only have a short life span before needing to be disposed of. Since 2010, any retailer that sells 31 kg of batteries per year, roughly the equivalent of one pack of 4 AA batteries per day, must take back used batteries for recycling. But what happens to these batteries after they are collected?
The Interactive Battery Recycling project, led by CDT students in Southampton, explains the process of recycling alkaline batteries by allowing visitors to shred a battery and then recover some of the materials from the residue.
The process shown in the display is broadly similar to the process used in industry. The battery is destroyed before being mechanically separated into different components. The next step is dissolving soluble components by neutral and then acid leaching. For safety reasons, the demonstration does not include the acid leaching process. After each leaching step, the solution is filtered. Finally, the metals are recovered from the solution. In this activity, by electroplating.
After the recycling process, examples of materials that could be recovered from recycling batteries of all kinds are displayed alongside some information about why these materials are likely, or unlikely, to be recovered.
Finally, there is the build a battery section. The visitors have seen what is in a battery, now it is time to put one together. Using materials you can find at home, copper coins, aluminium foil and kitchen roll soaked in vinegar, it is possible to build your very own batter.