by David Coy, Fleet Data Analyst

As electric vehicles are becoming more common, talks about batteries have become more frequent. However, even gas-powered vehicles have batteries – and these batteries are replaced more often than those of electric vehicles.

Car BatteryWith almost 1,400 assets in our fleet, we go through quite a few batteries a year. In fact, in 2020 we had to replace 13,020 pounds of batteries, while also purchasing 115 less batteries than we did in 2019. But what happens to the batteries we replace? Fleet has a robust recycling program, which includes battery recycling. When a battery can no longer be used, we send it to Northern Battery for recycling. The batteries are then sent to a smelter, where they can separate and send the raw materials to battery manufacturers to create new batteries. Little known fact: lead batteries have a 99% recycle rate, making it the world’s most recycled consumer product.

Recycling ProcessThe recycling process is fairly simple. The battery components get separated into three main categories: plastic, acid, and lead. The plastic is cleaned and crushed in order to form pellets. These pellets can be melted to be shaped and used into other plastic products – most likely into a new battery casing. The acid from the old batteries is purified and neutralized. During this process, it can stay in liquid form to be used in other batteries, or it can be turned into sodium sulfate to be used in other, more unexpected, products such as laundry detergent and glass. Lastly, lead is stored to let it dry. Once dry, it is smelted and refined with other elements to create alloys. This process is so efficient that it can be repeated almost indefinitely. Once the lead has been refined, it is molded, cooled, and packaged. After all these 3 main components have gone through the steps above, the end product is used to create new batteries that will be ready to be installed in your vehicle.Other uses for the recycled batteries include sporting goods, construction materials, x-ray and medical radiation protection, automotive parts, and plastic wheels.

Another battery that we are starting to use more often are rechargeable lithium-ion (Li-ion) batteries. Originally, we would only use this type of batteries to power small electric equipment like flashlights, diagnostic tools, and wireless computer mouses. Now, we have electric vehicles (EVs) that move using power stored in big Li-ion batteries. The latter have caused a lot of concerns when it comes to the environmental impact that they’ll have on the environment and that might discourage potential EV owners.

Before we discuss EV battery recycling, we need to understand one thing: the battery you see in combustion engine vehicles is not the same as the battery in electric vehicles. Other than the chemical composition, the first difference you’ll see is the life of the battery. Lead-acid batteries have a life of approximately 3 years, while Li-ion batteries used in an EV are usually warrantied for 8 years and are expected to last for the life of the vehicle. Second, Li-ion batteries for EVs are built differently. All EVs have different battery architecture, but for the most part they work like a Matryoshka doll (the wooden dolls that stack inside of one another). There is a big battery composed of smaller modules. Each module is composed of even smaller modules. The smaller modules are then made up of smaller looking batteries; like the ones you use for your TV remote. In other words, if there is an issue with the battery, specific components can be replaced without the need to discard the whole array of batteries.

EV Battery Pack


Lastly, Li-ion battery components are expensive, so it is in the EV manufacturer’s best interest to get the most back from each battery that has reached its end-of-life. Several manufacturing companies have identified this opportunity and are working on developing processes to recycle EV batteries within their own facilities. This will have two big positive effects: less battery waste and cheaper EVs as the components become less expensive. Currently, it is industry standard that approximately 50% of a Li-ion battery can be recycled. However, a Finnish company has developed a process that allows for 80% of the battery to be recycled. At this rate, the recycling process will be efficient enough to take care of the EV batteries that will come out of commission years from now. As a note, the first City of Madison EVs are not likely to come out of commission until the end of this decade.

You can help, too. If you have any type of batteries that no longer work, do not throw them away. Please bring them to any City Streets drop-off site. However, make sure you identify the type of battery you are disposing of, separate them, and follow the instructions listed in the City battery recycling program website.

This content is free for use with credit to the City of Madison - Fleet Service and a link back to the original post.