Battery drains fast, drops suddenly, or won’t charge fully? Sometimes software or a weak charger; sometimes chemically degraded cells. Clear signs, quick tests and when replacement makes sense.
1. Quick checks
- Check which app drains — Settings → Battery.
- Temporarily disable 5G, max brightness, constant location — retest.
- Another cable + enough wattage — incomplete charge may be port/cable.
- Note: % jumps, sudden shutdown at 20%, warm on light use.
- Swelling — bulging back, lifted screen = stop use, urgent shop visit.
2. When it's worn battery, software or drain
- Worn: Health below ~80%, much shorter life, sudden shutdown at low %.
- Software: background app, recent update, cloud indexing — watch 24–48h.
- Stops at ~80%: on iPhone often Optimized Battery Charging, a charge limit, or temperature — check settings before blaming port/cable.
- Temperature: old battery drains fast in extreme cold/heat.
- Swelling = urgent replacement — fire risk, not just runtime.
3. What NOT to do
- Don't keep using a swollen battery.
- Don't “calibrate” by repeated full drains — unnecessary Li-ion wear.
- Don't install shady “battery saver” apps.
- Don't DIY swap without experience — flex and seal risk.
- Don't blame battery for “won’t charge fully” without cable/port tests.
4. When to book diagnostics
- We measure battery state, drain and charging path — battery vs port.
- Replacement per model; timing depends on part and procedure — after inspection.
- Estimate on request; exact cost after diagnostics — no fixed online price.
- WhatsApp model and symptoms (runtime, swelling, shutdowns).
Sector 4, Bucharest. Phone battery diagnostics and replacement.
Still having the problem?
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Repairs in Bucharest, Sector 4 · Calea Șerban Vodă 43. Cost and timing are confirmed after inspection, before repair.
FAQ5
Battery drains fast — normal after 2 years?
Some wear is normal; half the runtime or sudden shutdowns suggest replacement. Check Battery Health.
Drops suddenly from 30% to 0?
Often degraded cells or sensor calibration. Retest after restart; if it persists — diagnostics.
Won't charge past 80% — battery?
iPhone Optimized Battery Charging or a charge limit stops at ~80% on purpose; temperature also matters. Android may have battery protection / limit. Only after ruling out settings: port, cable or battery.
New battery cost?
Depends on model and glued assembly. Quote after inspection — no made-up price.
Can I swap the battery myself?
Risky on many models. Shop avoids board damage and proper reassembly.