A lifted screen or bulging back on a phone that has spent years in a drawer is a reason to stop, not to see whether a charger brings it back. A swollen battery is damaged. The immediate task is safe handling and professional advice; recovering photographs and finding a replacement pack come later.
If the device is smoking, becoming dangerously hot, or otherwise appears to present an imminent fire risk, move away, keep others clear, and contact local emergency services. Do not attempt to continue this checklist beside an active incident.
Do not try to flatten or revive the battery
Do not press the case shut, puncture the battery, bend it back into shape, or run a charging experiment. The EPA identifies swelling as battery damage and a potential fire hazard. Its guidance is to seek direction from the manufacturer, retailer, or local hazardous-waste program when there is no immediate emergency.
A removable back cover does not automatically make a swollen battery safe to remove. If removal requires force, tools against the cell, or disturbing a stuck pack, leave it to a qualified service provider. Do not power the phone just to drain the battery before disposal.
For an iPhone, Apple’s safety guidance says to discontinue use when battery damage is suspected and assigns battery repairs to trained technicians. For another brand, find its equivalent instructions and explain the actual condition, rather than asking only for a routine battery replacement price.
Call before taking it anywhere
Tell the service center or recycler that the phone contains a swollen or damaged lithium-ion battery. Ask whether it accepts that condition, whether the whole device should remain intact, and what handling and transport procedure it requires. A location that takes ordinary used batteries may have a different process for damaged ones.
Until you receive instructions, keep people and pets away and avoid unnecessary handling. Keep it away from flammable materials if that can be arranged without putting yourself at risk. Do not put the device in a pocket, a crowded drawer, or a bag with keys while deciding what to do.
Do not mail it using an ordinary used-phone shipping label without confirming that the carrier and recipient accept damaged batteries and specifying the required procedure. A trade-in kit or generic return instruction is not confirmation for this particular condition.
Ordinary recycling bins are the wrong destination
The EPA’s consumer disposal guidance directs lithium-ion batteries and devices containing them to appropriate battery or electronics collection rather than household trash or municipal recycling. Crushing during collection and processing can create a fire hazard.
The right local service may be an electronics recycler, a manufacturer program, or a household hazardous-waste facility. Follow its damaged-battery instructions. General advice about taping terminals on loose used batteries does not mean you should pry a swollen cell out of a phone to reach its contacts.
What if the phone holds important data?
Tell the repair provider about the data before agreeing to work. Ask whether inspection or battery service can be performed without resetting the device, and what happens if the technician concludes it cannot be repaired safely. Do not assume a standard repair booking includes data preservation.
Check existing computer backups, cloud accounts, and previously removed memory cards from another device. You may already have the photographs without realizing it. Use a supported computer or phone to check those accounts rather than powering the damaged handset for one last synchronization.
If a qualified provider makes the phone safe to operate again, copy and verify the data before deciding on its next use. A replacement battery does not update the operating system, restore discontinued services, or guarantee that other aging components are sound.
Retiring the device can be the sensible repair decision
A collectible handset may justify specialist attention; an otherwise replaceable phone may not. Ask for the full service estimate and the provenance of the replacement part. Compare that with the value of the device to you, including the data, rather than with its original retail price.
For an undamaged old phone, arrange backup, account removal, and an appropriate erase before sale or recycling. For a damaged one, tell the recycler if personal data remains and ask about its data-handling service. Do not turn a battery-safety problem into a risky attempt to finish a factory reset at home.