PHONE REPAIR GLOSSARY / BATTERY & POWER / GRADE A BATTERY
Grade A Battery
A replacement battery manufactured to original equipment specifications — accurate capacity, proper safety certifications, and the quality tier used by reputable repair shops. Not all replacement batteries are equal, and the difference shows after 6–12 months.
What It Is
| Tier | What It Means | Expected Lifespan |
|---|---|---|
| OEM | Original Equipment Manufacturer — exact same battery the phone shipped with | 2–3 years to 80% health |
| Grade A | Manufactured to equivalent spec — accurate capacity, safety certified | 1.5–2.5 years to 80% health |
| Low-grade aftermarket | Often mislabelled capacity, no reliable certifications, higher swelling risk | 6–12 months before issues |
Grade A vs Cheap Aftermarket
- A low-grade battery may show 100% but actually have less physical capacity — you’ll notice shorter runtime within weeks
- Low-grade cells are more likely to swell in Singapore’s heat
- Cheap batteries often lack proper protection circuits, increasing overcharge and fire risk
At Certified Phone Repair SG, we use Grade A batteries across all brands. iPhone replacements reset battery health to 100%. Every battery comes with a 90-day warranty.
Related terms
- Battery Health — what to check before and after replacement
- Swollen Battery — what happens when battery quality fails
- Grade A Parts — how part grading applies to screens too
People Also Ask
What is the difference between Grade A and OEM batteries?
OEM means the exact battery Apple or Samsung would install. Grade A means manufactured to an equivalent specification. In practice, a Grade A battery from a reputable source performs comparably to OEM at a lower cost.
How do I know if a repair shop used a quality battery?
Ask before the repair: what grade or brand of battery will you use? After replacement on an iPhone, Settings → Battery → Battery Health should show 100%.
Are cheap aftermarket batteries safe?
Low-quality aftermarket batteries can have inaccurate capacity labelling, missing safety circuits, and higher swelling risk — especially in Singapore’s heat.
Further reading
- How to Make Your Phone Battery Last All Day: 15 Proven Tips
- 5 Signs Your Phone Battery Needs Replacement
