Battery Replacement
This is the replacement side of the battery guide: what to check before ordering, how each brand behaves, and how to get the old cell out without damaging the chassis.

Three routes, and you only need one of them
Take the route that matches the handset on your bench.
iPhone
Take this route for the highest-volume battery job in a UK shop. The older chassis come out with pull tabs; the newer ones need a different approach and carry pairing behaviour.
Samsung and Pixel
Take this route for the Android handsets that dominate UK repair volumes. Adhesive strength and frame construction vary a lot between the A and S series.
Huawei, Xiaomi and Poco
Take this route for the brands where genuine parts are harder to source and the aftermarket quality varies more between suppliers.
Before you order the cell
Two checks decide whether the battery is the fault, and both take less time than a second repair.
Reading the health figure properly
The battery health percentage is a useful indicator and a poor diagnosis. It tells you how the cell reports itself, not whether the drain, the shutdown or the heat is coming from the cell. A phone that shuts down under load with a healthy figure is usually an electrical fault, while a phone with a low figure that behaves normally may have years of service left. Confirm the symptom pattern first, then decide whether to quote a battery.
Capacity claims between suppliers
Two batteries with the same printed capacity do not behave the same way, because the number describes a nominal figure rather than the cell inside. What matters in practice is consistency: whether the supplier’s cells behave the same way across batches, and whether the connector and the flex match the original closely enough to seat properly. Comparing suppliers on measured runtime and return rates tells you more than comparing the labels.
What actually decides whether a battery job sticks — four things
Four variables, and the last one is the reason a phone comes back a week later.
Whether the cell was the fault
Drain, heat and shutdowns can all come from the charging path or the board. Confirm the symptom pattern before quoting a battery.
The cell you fitted
Consistency between batches matters more than the printed capacity, and the connector has to match the original closely enough to seat.
How the old cell came out
Adhesive removal decides whether the chassis survives the job. Pull tabs that snap turn a twenty-minute repair into an hour.
Calibration and pairing
Some handsets need the new cell recognised before the gauge behaves normally, and recent iPhones warn when the pairing does not match.
Where to go from here
If the battery is not the fault, the next guide is the one about the charging path.
Battery replacement questions
The short answers, each linked to the article set behind it.
How long should a phone battery last?
Expect two to three years of normal use before capacity becomes noticeable, and longer if the phone is charged sensibly. Heat is the biggest variable: a phone that charges under a pillow or in direct sun ages faster than one charged on a desk, whatever the brand.
Does a replacement battery need calibrating?
Some handsets report the new cell’s capacity more accurately after a full charge and discharge cycle, and a few need the part pairing to complete before the gauge settles. Running the phone to shutdown once and charging it fully is the usual approach where calibration applies.
Is an aftermarket battery as good as a genuine one?
It depends on the supplier rather than the category. Some aftermarket cells measure close to genuine and last as long; others meet the label and not the behaviour. The practical test is batch consistency and return rate, which is why buying from a supplier who can show both matters more than the brand on the wrapper.
What should I do if the old battery is swollen?
Treat it as a safety item, not as routine waste. Discharge and isolate it, avoid puncturing or bending it, and dispose of it through a proper battery route rather than putting it in general waste. The handling guides cover the sequence for damaged and swollen cells.
Should I quote a battery replacement on a phone that also has a screen fault?
Quote both and explain the order, because the screen usually has to come off to reach the battery on modern chassis. Doing them together is cheaper for the customer than two separate repairs, and it avoids opening the same phone twice.
Ask for battery pricing by model
Send the models you replace most and your typical monthly volume. You will get the battery options for those handsets with trade pricing, plus the pairing notes for the models that need them.
Ask for a battery quote