There is a decent chance you have a small stash of dead lithium-ion batteries somewhere: a phone that gave up, a laptop pack that swelled, a drill battery that no longer holds a charge. Most of them contain cobalt, and almost none of them belong in your bin. In the UK there are more drop-off points for spent batteries than most people realise, and using one takes about as long as a trip to the supermarket. What follows is how to do it properly, from working out what you have to understanding where the cobalt ends up.

Which lithium-ion batteries actually contain cobalt

Cobalt sits in the cathode of several common lithium-ion chemistries. Lithium cobalt oxide (LCO) turns up in phones, tablets and some laptops. NMC and NCA blends dominate power tools, e-bike packs, electric vehicle batteries and many modern laptops. If a cell is labelled "Li-ion", "Li-ion polymer", or carries a chemistry code such as NMC, NCA or LCO, there is cobalt in it worth recovering.

Two exceptions are worth knowing. Lithium iron phosphate cells (marked LiFePO4 or LFP) contain no cobalt at all — they should still be recycled, just not for cobalt. Lead-acid car batteries and nickel-cadmium tool packs follow entirely different routes: garages and many council sites take lead-acid, while NiCd packs belong at a hazardous waste or electricals point rather than a shop battery bin.

Finding a take-back point near you

You have more options than you think. Most are free, and none of them require an appointment.

• Supermarkets and DIY stores. Most large supermarkets and many DIY sheds keep a battery bin near the entrance or the tills. Under UK producer responsibility rules, larger retailers that sell portable batteries must offer free take-back in store — you do not need to buy anything or have bought the battery there.
• Electrical retailers. Currys and similar chains accept waste batteries and small electrical items in store. Useful if you are also getting rid of the device itself.
• Household waste recycling centres. Most councils provide a battery container and a separate area for waste electricals. Ring ahead for e-bike packs or anything oversized, because acceptance varies by site.
• Kerbside small electricals collections. A growing number of councils collect small electricals in a carrier bag on bin day. Batteries usually need to be taped and bagged separately, so read your council's instructions before putting them out.
• Where you bought it. E-bike shops and power tool suppliers increasingly take packs back. EV batteries are normally handled by the dealer, or by the authorised treatment facility when the car is scrapped.
• Producer schemes. Compliance schemes and some manufacturers run their own collection points in shops and workshops. Your council's website or the Recycle Now locator will show what is closest.

Preparing cells for drop-off: step by step

1. Remove the battery only if it is designed to come out. If it is glued into a phone or laptop — as most are — do not pry at it. A punctured cell is a genuine fire risk. Hand in the whole device at a waste electricals point instead and let the recycler separate it.
2. Check for damage. Swollen, dented, corroded or leaking packs need different handling, covered below.
3. Wipe your data. Factory reset phones, tablets and laptops, and take out SIM and memory cards before they leave your possession.
4. Tape the terminals. Cover exposed contacts with clear sticky tape or insulating tape, or drop each cell into its own small plastic bag. A handful of loose cells rattling in a tin can short against each other and start a fire.
5. Store cool and dry until you go. Not in a hot car, not against a radiator, not in a damp garage. A lidded tub in a hallway cupboard is fine.
6. Hand over in person where you can, and mention it if anything is damaged so staff can store it properly.

Swollen, damaged or leaking packs

These are the ones that cause trouble. Do not charge them, do not puncture them, and do not try to squeeze one back into a device. Move it away from anything flammable — ideally outside, in a metal container with a lid, well away from the house. If a pack is hissing, smoking or getting hot, keep away from it and call 999.

For a swollen but stable pack, ring your council first. Many recycling centres accept damaged batteries in a hazardous waste bay; some will not take loose damaged cells, and a few offer a booked collection. Retailers may reasonably refuse visibly damaged batteries, though they can often advise on a local alternative. What you must not do is put it in a household bin, a kerbside recycling box, or a shop battery bin. One damaged pack can set a collection lorry alight, and those fires are a real problem for waste crews.

What happens to the cobalt you hand in

Your battery first goes to a sorting site, where chemistries and formats are separated and non-battery items are pulled out. From there it goes to a specialist recycler, where one of two routes is usually taken.

In smelting, whole batteries are fed into a furnace and the cobalt, nickel and copper are recovered together as an alloy. In hydrometallurgical processing, batteries are shredded and processed into what the industry calls black mass, then leached with acid and separated into individual chemicals — cobalt sulphate, nickel sulphate, lithium carbonate.

Those chemicals are the point of the exercise. Battery makers need cobalt at high purity for new cathodes, so recovered material normally goes through further refining before it is usable. Much of the lithium-ion material collected in the UK is processed at specialist plants here or shipped to established facilities in Europe. Recycling recovers the metals, not the original battery — a new cell is built from refined chemicals, which is why clean sorting at your end matters more than it sounds.

Make it a monthly habit

Keep a small lidded tub where you store tools or charging cables. Tape each cell as it dies and drop it in, then empty the tub at the supermarket or recycling centre once a month. It takes five minutes and keeps the fire risk out of your bin lorry.

If you run a business — a shop, workshop or office — the rules are stricter: waste batteries are covered by your duty of care, and if you sell portable batteries you may have take-back obligations of your own. Check with your compliance scheme or the Environment Agency rather than guessing, and take professional advice if your volumes are significant.

Photo: Ralphs_Fotos / Pixabay