Used batteries that are sold as usable are not “recycled” batteries. They are batteries with useful life remianing that were removed from cars, computers and other devices.
All batteries are constructed of materials that are hazardous to people and the enviornment if they aren’t handled respinsibly. If your batteries are depleted and won’t take a charge, take or give them to a hazardous materials recycling center.
Batteries brought in for “recycling ” are deconstructed to recover materials that can be safely refined and incorporated into new products. It may be called post-consumer waste materials, or recycled material. In most cases this process is either less expensive than mining previously unused raw materials or mandated by law. If a product is labeled as containing some reycled materials, it should not have a higher price than if it didn’t.