When identifying the type of button cell battery you may have, please be sure to differentiate between silver oxide and lithium or alkaline batteries. These batteries are identified by an alphanumeric code. Typically the first letters in the alphanumeric code will identify the type of battery. The first letters (LR) indicates an Alkaline battery and may be thrown in the trash. Batteries with the first letters (CR) indicates a Lithium battery, (SR) indicates a Silver Oxide which contain heavy metals. Batteries that are identified by a letter (P) are rechargeable and contain heavy metals and/or mercury. Button Cell batteries contain heavy metals or mercury and can be taken to any Household Hazardous Waste event or check with a local home improvement store or every Best Buy store has free kiosks, just inside the door, for customers to drop off rechargeable or button batteries for recycling.