In our day to day we use batteries to operate many electrical appliances. Although very useful and sometimes rechargeable, Battery Waste have a finite life cycle and it is therefore very important that we know what to do with them once they are exhausted. In fact, these small sources of energy are highly polluting because they are made of heavy metals and chemical compounds that can be very harmful if not recycled correctly.
Why do batteries pollute?
Batteries are made of different metals or metal alloys, including manganese dioxide, iron, zinc, electrolyte, cadmium, and graphite.
Once used, they become toxic waste. The main problem with disposing of batteries is that, if we mix them with organic Battery Waste, they can end up in a landfill. Over time, they will lose their protective ‘casing’ (usually plastic), and their constituent metals will seep into the ground, contaminate groundwater and enter the human food chain.
This contamination process is long. Since none of its components are biodegradable, its effects can last for decades, and even centuries . What’s more, natural elements such as heat, rain or the acidity of the soil itself can accelerate it.
Why recycle batteries? Are they all bad for the environment?
Yes. Regardless of their composition, all batteries are manufactured with non-biodegradable metallic materials and components that can be very toxic to people and the environment.
It is not a question of size either. Although the batteries are small, their contamination capacity is high. For example, a mercury button cell can contaminate about 6,000 thousand liters of water, and a conventional battery up to 167,000.
Still, it is true that some types of batteries pollute less than others :
- “Dry batteries” (“saline” or “zinc-carbon”) contain little mercury (0.01%) and their degree of toxicity is lower.
- “Alkaline batteries” have mercury content close to 0.5%, which is why they are considered toxic.
- “Rechargeable batteries”, despite not having mercury, contain cadmium, so they are also considered toxic.
- Button batteries, which can contain up to 30% mercury, are defined by their high toxicity and are very dangerous for the environment.
What should I do with my used batteries?
Batteries and accumulators and the environmental management of their waste, the percentage of collection of batteries for recycling must be, at least, 45%.
For this reason, there are more and more special containers for recycling batteries. These deposits are located in specialized establishments (for example, in hardware stores or appliance stores), although we can also find them in some supermarkets. Used batteries can also be deposited in the “clean points” of the town halls.
How are batteries recycled?
Recycling batteries allows up to 75% of the materials from which they are made to be reused.
Once deposited in the containers to recycle batteries, they are transferred to a recycling plant where the mercury will be separated from the rest of the metals and materials to be recovered .
There are several techniques for treating piles depending on their composition . Normally, conventional cells are subjected to a mechanical crushing process under nitrogen-cooled conditions. Thus, a powder is obtained that is recovered as a diverse raw material in the form of ferrous metals, carbon or zinc.
Button batteries, since they have a higher amount of mercury, are subjected to a process of distillation of iron, nickel and cadmium, metals that will be used again.
In some cases, the piles are buried in controlled landfills until the separation of the metallic parts and the saline fraction can be carried out. Afterwards, they undergo a physicochemical treatment for the recovery of magnesium and zinc.
5 Key Points of Battery Recycling
- Batteries are very polluting and we must avoid their use whenever we can . The general recommendation is to opt for rechargeable batteries. This allows you to generate less waste and avoid using almost dead and new batteries at the same time.
- Batteries must always be recycled . The correct thing is to deposit them in their own collection containers. And of course they should never be thrown in the garbage or to the toilet.
- Used batteries should not be in contact with new ones , as they could be damaged.
- All batteries must be recycled , regardless of their size and components.
- Efficient battery recycling goes through separate collection . Find your nearest collection point to recycle used batteries.