El-Kretsen has around 5,000 battery bins. The batteries from these bins and the integrated batteries that are removed from other waste products amount to around 3,000 tonnes when added up. All batteries are pre-treated before being forwarded for disposal or materials recovery.

  1. The pre-treaters sort the batteries according to size and constituent parts. The first stage involves the filtering out of button cell batteries. Some of these contain small amounts of mercury. You can read more about them below.
  2. Next comes the manual sorting into fractions, depending on what the batteries contain. Some content (like cadmium) is removed to be phased out of the recycling loop. Other components (like lithium) are removed to be forwarded for materials recovery.
  3. Around 80 per cent of all batteries collected are alkaline disposable batteries.
  4. The different fractions are crushed and treated in a closed system. When it comes to lithium-ion batteries, it is very important that the metal covers can be safely separated from any reactive matter in order to be able to recover the materials. Alkaline batteries are mainly composed of metal, plastic and a mass containing organic matter. Through the process, metal and plastic are sorted out for recycling, while the organic material is disposed of as hazardous waste.

Alkaline batteries – Our most common battery

Of all the batteries that are collected in Sweden, the largest part is Alkaline, as much as 75%. Alkaline batteries are the most common single-use batteries – the ones you would put in your smoke detector, a remote control or in your children’s toys. Whether these batteries are round, square or cylindrical cells, they all have one thing in common: They are not rechargeable. Since 2009, all alkaline batteries are recycled. The primary gain is the metal casing. The inside is largely made up of zinc and manganese, which, once processed, is known as the “black mass”. Today, we are able to recover the metal from the battery casing and a large part of the zinc, and there is ongoing research into how we could recover more of the battery content.

An alkaline battery consists of:

Manganese (cathode): 37%

Iron: 23%

Zinc (anode): 16%

Paper and plastic: 24%

Lithium batteries – A modern solution

There are many kinds of lithium batteries, but in everyday life we primarily interact with the following two:

Primary lithium batteries (non-rechargeable) and lithium-ion batteries (rechargeable).
We don’t often see primary lithium batteries. They are very small and found in watches, computers and toys. Because of their size, they are quite difficult to recycle. They tend to be converted into new energy instead.

The other group, lithium-ion batteries, are found in modern lap-top computers, telephones, games, etc. as well as in electric vehicles. This is the best battery on the market today, both with respect to their power and to the environment. As much as 90 per cent of the most common lithium-ion batteries can be recycled.

A lithium-ion battery consists of:

Aluminium: 15-25%

Copper: 5-15%

Lithium: 1-10%

Cobalt: 1-15%

Nickel: 1-15%

Iron: 1-20%

Paper and plastic: 6-15%

Cadmium batteries – Eco-villains

Cadmium batteries (which are also known as “nickel-cadmium batteries”) contain the hazardous heavy metal cadmium. Luckily, these batteries are not common these days. This is because an environmental tax has been imposed on them. This makes it more expensive for manufacturers to put cadmium batteries – rather than other more environmentally-friendly battery types – in their gadgets. Another reason why we don’t find many cadmium batteries on the market these days is that more powerful batteries have appeared, like lithium batteries. However, old computers, telephones, tools and other gadgets may still contain cadmium batteries.

A cadmium battery consists of:

Iron: 40%

Nickel: 22%

Cadmium: 15%

Paper and plastic: 23%

Nickel-metal hydride – The cadmium battery’s successor

When cadmium batteries were phased out, they were replaced by the nickel-metal hydride battery (NiMH).

Nickel-metal hydride batteries are often rechargeable and may come in the shape of cylindrical cells just like ordinary alkaline batteries, but the difference is that they can be recharged using a battery charger.

Nickel-metal hydride batteries do not contain any heavy metals, but should naturally, still be deposited in a battery bin or taken to your local recycling station once they have reached the end of their useful life. Even if they can no longer be recharged, up to 90 per cent of a NiMH battery can be recovered and recycled.

A nickel-metal hydride battery consists of:

Nickel: 33%

Iron: 30%

Lanthanide: 10%

Cobalt: 3%

Manganese: 1%

Zink: 1%

Lead batteries – Large and heavy

Lead batteries are common in our cars, but can also be found in some garden tools and mopeds. Large batteries are handed in to a recycling center or when you buy a new battery in a shop or gas station, for example.

When the batteries arrive at the facility, they are drained of sulfuric acid, which can be neutralized to water by adding sodium hydroxide. The lead cell is fed into a blast furnace. In this thermometallurgical process, lead, slag and slag are extracted. The lead is alloyed and resold, while the slag and cutting stone are deposited in Boliden-Bergsöe’s own landfill facility. The recycling rate for lead batteries is 65-74%, and the statutory requirement is 65%.

Electric car batteries

As much as 30 per cent of the weight of an electric vehicle can be attributed to its battery. It is not uncommon for an EV battery to weigh 300–600 kilos. The batteries of electrically powered forklift trucks, machines and lorries can vary even more in weight.

EV batteries are packed in a secure transport container and transported by carriers with specially trained drivers.

The battery is drained of any remaining power and if possible, we see to it that this power is used locally. After this, the battery is manually dismantled.

In order to recover as much of the materials as possible, the battery’s different components are sorted and treated in several stages. Material that cannot be reused is recycled or disposed of in the best way possible, bearing environmental requirements in mind.

Mercury batteries

Where batteries are concerned, the heavy metal mercury is mainly found in some button cell batteries. These are small and round and can be found in anything from watches to singing birthday candles and remote controls. Mercury is a chemical element and once released it cannot be broken down. Instead, it builds up in the ground, the water and living organisms, which is dangerous both to the environment and to our health. October 2015, Sweden banned the sale of batteries and products with integrated batteries in which mercury accounts for more than 0.0005 percent of the weight. Existing stock is however allowed to be sold off.

El-Kretsen collects these batteries in our designated battery bins and by retrieving them manually from the WEEE we collect and dismantle. All batteries are then sorted according to their chemical content before moving on to the recovering phase, or in the case of mercury, being removed and phased out of the recycling loop. Button cell batteries are sorted on a shaking table where the batteries below a certain size are sorted out into a fraction of their own. For the safest possible handling, all small button cell batteries are processed in the same way, even though only a small proportion of them contain mercury.

To provide a better picture of how common an element mercury is in our everyday batteries, let’s put it like this: For every 2,000 kilos of assorted batteries we process in our sorting facilities, around 1 kilo contains mercury. Of this kilo, metallic mercury accounts for a few percent. All in all, we handle some 3,500 tonnes of batteries every year. Less than two tonnes of these actually contain mercury.

Any waste with a proportion of mercury exceeding a certain limit is required by law to be forwarded for final disposal. The law also includes information on how this is to be achieved. In Sweden, final disposal equals underground storage, but there are no such facilities in the country (as of yet). Since 2014, all batteries containing mercury collected by El-Kretsen are shipped to Fortum Waste Solutions in Kumla. Here they are being temporarily stored. Once the mercury has stabilised it will be forwarded for final disposal. One of the options used for final disposal of mercury is former salt mines in Germany. Right now, circular economy company Ekokem is in the middle of a procurement process to find the company that will be treating their mercury waste in the future. To ensure correct handling, Ekokem plans to carry out revisions of the facility that is ultimately selected. Also, the entire process chain will remain inside the EU to make sure that the same regulations apply to all parties involved. El-Kretsen remains in constant contact with Ekokem to ensure that all the batteries we collect that contain mercury will be handled safely and in accordance with environmental legislation.