Button Batteries Illegal in Garbage & Drains Contains Mercury Hazardous Waste Through the IWMA’s SLO Take Back Program, every retailer that sells household batteries in San Luis Obispo County must take those items back from the public for free. Batteries are sent from take back locations to be safely recycled. To be recycled through this program, batteries should be fully discharged. Button batteries should have tape placed over the metal contacts. Never Throw in the Trash Button batteries sometimes contain mercury. Even if they don’t, they are banned from the trash because they contain other toxic and corrosive chemicals. Dispose of them as Household Hazardous Waste. Did You Know? Why Is Mercury Still in Batteries? Mercury is included in batteries for a reason: It’s used as a stabilizer and gives batteries a longer life. In 1996, the Mercury Containing and Rechargeable Battery Management Act prohibited the sale of mercury-oxide batteries in the U.S., except for select applications.