Batteries for Christmas toys and gifts: what to buy, and button battery safety

The short answer: check the box before Christmas morning

Look at every boxed present now, while there is time to shop. The pack says what the toy takes and how many, and "batteries not included" is printed on it when you need to buy them. Most toys take AA or AAA cells. Some bigger toys take C or D, a few take a 9V, and small gadgets and novelties often take button or coin cells.

Write the list down: the size, and how many each present needs. Then you can buy once, in the right sizes, instead of hunting for a corner shop on Christmas Day. The table shows what typically uses each size. It is a rough guide only, so go by the pack or the manual.

Alkaline or rechargeable?

An alkaline AA gives a nominal 1.5 volts. A rechargeable nickel-metal hydride (NiMH) AA gives a nominal 1.2 volts, according to Energizer's datasheets for each type. Many toys run on either, but check first. A few makers say not to use rechargeables at all: VTech's manual for its Challenger Laptop says "Rechargeable batteries are not recommended" and recommends new alkaline batteries. So read the battery notice in the manual before you swap.

Rechargeables pay for themselves in toys that get played with every day and work through a set quickly, such as a remote-control car or a games controller. Low self-discharge NiMH cells are the type to buy, because they keep their charge in a drawer: Panasonic says its standard AA eneloop cells keep 70% of their capacity even after 10 years in storage, based on its own testing. In low-drain things like a clock or a TV remote, a pack of alkalines lasts a long time and is the simpler choice.

You also need a charger made for NiMH cells. Charging takes hours, not minutes, so put the cells on charge the day before and follow the charger's instructions. Toy manuals usually include a battery notice. VTech's says non-rechargeable batteries are not to be recharged. It says rechargeable batteries are to be removed from the toy before being charged, and only charged under adult supervision. It also says different types of batteries, or new and used batteries, are not to be mixed.

How many to have in for Christmas Day

A simple rule: for each toy, one full set fitted and one spare set beside it. For the toy that will be played with all day, often a remote-control car, make that two spare sets, or have a second set of rechargeables charged and ready. Count by the pack, not by guesswork, and buy a few extra AAA cells for remotes and games controllers.

Keep each spare set together in its packaging, and put new cells in all at once rather than mixing old and new. These are the same AA and AAA cells your torches and radio take, so whatever is left over after Christmas goes straight into the power-cut drawer.

Button and coin batteries: the part that matters most

Button and coin batteries are the small, flat, round cells in key fobs, remotes, musical cards and many toys. The Office for Product Safety and Standards (OPSS) says they can badly injure or even kill a child if swallowed. It explains why: the battery reacts with saliva to create caustic soda, the chemical used to unblock drains. If it gets stuck in the food pipe it can burn a hole and cause internal bleeding or even death, and if it gets into the stomach it can also cause significant tissue damage.

OPSS says the larger lithium coin cells, about the size of a five pence piece, are the most dangerous, and that smaller batteries can be pushed into ears and noses, causing serious injuries if not found. Flat batteries are still a risk: OPSS says dead button batteries can still have enough power to badly hurt a small child. The NHS says to keep button batteries well away from babies and small children, as they can cause severe internal burns if swallowed. OPSS puts it plainly: it sounds scary, but there are simple ways to keep your child out of danger. The next two sections set them out.

If you think a child has swallowed one

OPSS says: if you think your child has swallowed a button battery, take them straight to the nearest A&E department or call 999 for an ambulance. The Child Accident Prevention Trust (CAPT) says to trust your instincts and act fast, and not to wait to see if any symptoms develop.

Do not let your child eat or drink, and do not make them sick. Both OPSS and CAPT say this, and Great Ormond Street Hospital explains that making a child sick could cause more damage as the battery comes back up.

At the hospital, tell the doctor that you think your child has swallowed a button battery, CAPT says. If you can, take the battery packaging or the toy or gadget it powers with you. OPSS and CAPT both say this helps staff identify the battery. Great Ormond Street Hospital adds: do not delay going to hospital if you cannot immediately see what they swallowed.

Symptoms may not be obvious. OPSS says a child might be coughing, gagging or drooling, or pointing to their throat or tummy. CAPT says one sign specific to swallowing a button battery is vomiting fresh, bright red blood, and if that happens, get immediate medical help. CAPT also covers honey, which you may read about: it explains why honey is not a simple answer, notes that honey should not be given to children under 1, and says the advice from doctors in the UK is that, unless you have a long distance to the nearest A&E, getting to hospital as quickly as possible is the number one priority.

Where they hide at Christmas, and how to keep them out of reach

OPSS lists everyday things that use button batteries: robot bug or fish toys, fidget spinners with LED lights, slim remote controls, car key fobs, calculators, scales, gaming headsets, watches, hearing aids, nightlights and novelty items like singing Santas. RoSPA asks for extra care with musical greeting cards, flameless candles, remote controls and electronic devices, because most of these will not have lockable compartments. CAPT says to look around your home for them, and to think toys, lights, remote controls and more.

Check the battery compartments. OPSS says that under product safety regulations, button battery compartments in toys are required to be secured. Look for a compartment held shut by a screw. If you find something powered by button batteries where the compartment is not secured by a screw, OPSS says to move it out of reach of small children, and if it is faulty, get it fixed or get rid of it safely. RoSPA says children should not have access to products whose battery compartment is not secure. CAPT says to check for products with loose backs and button batteries that have dropped out. You can report faulty toys to your local Trading Standards.

Store spares out of sight and reach. OPSS says not to leave them loose in drawers or on surfaces, and to watch out when opening multi-packs in case they fall on the floor. Great Ormond Street Hospital says to keep new batteries in their original packaging out of children's sight and reach, and to buy toys from reliable sources. When you take a flat one out, OPSS says to get rid of it immediately: store it securely and recycle it properly and promptly. CAPT suggests keeping used batteries in a box up high until you take them to the battery recycling bin at the supermarket, and Great Ormond Street Hospital says not to store them up to dispose of in one go. OPSS also says to teach older children why button batteries are dangerous and not to give them to young children.

Lithium batteries and chargers in new gifts

Phones, tablets and other rechargeable gifts usually have lithium batteries inside. London Fire Brigade's advice is to always use the charger that came with the device, and if you need a replacement, to choose a branded, genuine product from a supplier you can trust. It says it is best not to leave a phone plugged in overnight, and never to cover chargers or charging devices, which includes a laptop power lead in bed.

On its e-bike and e-scooter charging page, London Fire Brigade says batteries should always be charged on hard, flat surfaces where heat can dissipate. For phones and tablets, that means a desk or worktop rather than a bed or sofa. If a battery starts swelling or expanding, it says to stop charging immediately, turn the device off, not remove the casing or tamper with it, and contact the manufacturer or a certified technician. Our lithium battery guide has the rest.

Where to take flat batteries

Batteries do not go in the household bin. GOV.UK's guidance says you can take most waste batteries to your local supermarket, or any other big shop nearby that sells over 32 kg of batteries a year, where there should be a collection point. That covers AA, AAA and 9V batteries, button batteries and rechargeables. It says the terminals of lithium batteries should ideally be taped up first, to prevent any risk of fire.

Batteries that are built into a device and cannot be taken out, such as in calculators and e-cigarettes, are treated as electrical products instead. The whole item goes to your local household waste recycling centre, or back to the shop if you are buying a replacement, as retailers must take the old one for free on a like-for-like basis. GOV.UK notes that lithium-ion batteries can catch fire if dumped in your rubbish bin, particularly if they get wet or are damaged.