Many iPhone users notice their iPhone battery health dropping but are unsure when it becomes a real problem. This uncertainty often leads to poor performance and frustration.
iPhone battery health is considered bad when it drops below 80%, as performance and capacity significantly decrease at this point.
I have helped many clients replace batteries right before they completely fail, and I know the signs. Let’s go through each key percentage level so you know exactly when to replace iPhone battery.
At what percentage should I replace my iPhone battery?
Many people keep using their iPhone until it shuts down unexpectedly. This can damage the phone and disrupt your work.
Apple recommends replacing your iPhone battery when its health drops below 80%, as performance throttling often starts at this level.
When the battery health percentage falls below 80%, the battery can no longer hold a full charge. The phone may slow down to prevent unexpected shutdowns. I have seen customers try to ignore this, but the device eventually becomes frustrating to use. Replacing the battery early avoids bigger problems.
Signs it is time to replace your battery
- You charge your phone more than twice a day.
- Your phone shuts down when the battery still shows 20–30%.
- Apps load slower than before.
- The battery swells or the screen starts lifting.
| Battery Health % | Status | Recommendation |
|---|---|---|
| 90–100% | Excellent | No action needed |
| 80–89% | Fair | Monitor performance |
| Below 80% | Poor | Replace battery soon |
In my business, we always test iPhone batteries before replacement. This ensures customers know exactly why a change is needed. Many clients choose to replace at 82–85% health if they rely heavily on their phone for work.
Is 70 percent battery health good for iPhone?
It is common to hear someone say, “My battery is at 70%, but it still works.” What they don’t see is the hidden performance loss.
70% battery health is not good. At this level, your iPhone’s battery capacity is 30% lower than new, leading to faster drain and possible shutdowns.
When a battery reaches 70% health, it is already far past Apple’s service recommendation. You will likely need to charge your phone multiple times a day. For business users, this becomes a serious inconvenience.
Why 70% is risky
- Battery cycles are usually over 800 at this point.
- Internal resistance increases, making charging slower.
- High-load tasks like GPS or gaming will drain the battery in minutes.
I once had a Spanish wholesale client who used 70% batteries in refurbished iPhones to save costs. After a few months, returns increased, damaging his business reputation. Now he replaces any battery under 80% before selling.
Is 76% battery health ok?
Some users believe that being slightly above 75% is fine. The reality is different.
76% battery health is already considered poor and will cause noticeable performance and runtime issues.
At 76%, your battery has lost about a quarter of its capacity. Light users might still get through the day, but heavy users will feel the drop quickly.
The performance effect
- Standby drain becomes noticeable overnight.
- Charging to 100% takes longer but drains fast.
- iOS may reduce peak performance automatically.
From my years in mobile repair, I can say that customers often complain about heating issues at this level. The weakened battery works harder to deliver power, especially during demanding tasks.
In wholesale supply, I always warn my partners: selling a device with 76% battery health often results in complaints within weeks.
Is 85% battery health good after 2 years?
It sounds normal for a battery to lose capacity over time. But is 85% still “good”?
Yes, 85% battery health after two years is good and means your iPhone has been well maintained.
At 85%, you still have most of the original capacity. The phone should last most of the day under regular use.
Factors that help maintain 85% after 2 years
- Charging between 20%–80% most of the time.
- Avoiding overheating while charging.
- Using original or certified charging cables.
From a supplier’s perspective, I can say that many customers are satisfied with refurbished iPhones if the battery health is at least 85%. It adds resale value and customer trust. However, if you are a heavy user, you might still choose to replace it for maximum uptime.
Conclusion
Battery health below 80% is considered bad for iPhones, and timely replacement prevents performance loss and frustration.
