Heisen
Herald
Hello folks,
Since the launch of the iPhone 15 series, Apple has doubled the official battery cycle lifespan from 500 to 1,000 cycles. This means the battery is now rated to retain 80% of its original capacity after 1,000 full charge cycles.
That’s a significant leap, especially considering lithium-ion battery technology hasn’t fundamentally changed in the past two decades.
So, how did Apple manage this improvement? I believe the key lies in charging optimizations, not the battery chemistry itself. iOS now includes features like Optimized Charging and Charge Limit, which can significantly reduce battery stress over time.
I’ve personally set the iPhone to stop charging at 80%, but that is just a fail safe, I usually stop before that manually, I created a shortcut which runs an alarm when battery is charged to 60%, and I’m taking a few extra steps to see just how long a single battery can last under preventive conditions.
Note: I did fully charge and drain the phone once after 6 months for calibration purposes, which I now regret, cause it was not needed. But it happened only once in the first year, so hopefully not a big deal.
Activation Date: May 8, 2024
Screenshot taken: 15 days later
After a full year, the phone has only gone through 106 charge cycles. The battery's original capacity was 4467 mAh, and now it's at 4451 mAh, a loss of just 16 mAh, or ~0.35%. That’s 99.65% of the original capacity still intact!
So theoretically, at this pace, the battery would take over 55 years to reach 80% capacity.
I googled and found that lithium batteries degrade faster after a few years, especially after 500+ cycles, or with heat, deep discharges, etc. So while 55 years is fun math, it’s not realistic.
In practice, I’d expect around 5–10% loss per year after a few years, meaning I’ll likely hit 80% in 5–8 years, depending on real world variables.
If the phone survives and this forum still exists I’ll keep posting updates annually. It’ll be interesting to see how well the iPhone 15 plus battery holds up long term under careful usage.
Placing a google doc link here, cause I won't be able to edit the original post after some time.
Later Updates
Let’s see how far we can really stretch a modern iPhone battery!, backed by real world data.
Since the launch of the iPhone 15 series, Apple has doubled the official battery cycle lifespan from 500 to 1,000 cycles. This means the battery is now rated to retain 80% of its original capacity after 1,000 full charge cycles.
That’s a significant leap, especially considering lithium-ion battery technology hasn’t fundamentally changed in the past two decades.
So, how did Apple manage this improvement? I believe the key lies in charging optimizations, not the battery chemistry itself. iOS now includes features like Optimized Charging and Charge Limit, which can significantly reduce battery stress over time.
I’ve personally set the iPhone to stop charging at 80%, but that is just a fail safe, I usually stop before that manually, I created a shortcut which runs an alarm when battery is charged to 60%, and I’m taking a few extra steps to see just how long a single battery can last under preventive conditions.
Charging Setup
- Cooling during charging: Instead of removing the case daily, which causes scratches, I place an 80mm fan over the phone while charging during the summer to help dissipate heat and minimize thermal buildup.
- Charge range: I usually keep the battery between 40% and 60%, will be increasing this range over time to maintain the same daily battery life as capacity naturally declines.
- User profile: My wife has been using this phone since Day 1. She’s a teacher with consistent daily usage, around 2 hours of screen-on time daily.
- Software: The phone is running iOS 17.4.1, and I plan to keep it on this version to reduce variables.
- Background Apps: All background apps are disabled. Everything still works fine.
- Sync: All iCloud syncing is disabled, except iCloud Drive, health, contacts and whatsapp, just the important stuff.
- Wireless: Wifi and mobile data is ON 24x7, only 4g LTE, 5g is disabled. Bluetooth is off.
- Low Power Mode: Low power mode stays ON 24x7, no lags found.
- Apps: Apps are never closed explicitly. User just swipes up from the bottom to go back and runs another app, or just switches through app switcher.
- Charger: Original 20W charger, with original cable, the phone is charged daily.
Note: I did fully charge and drain the phone once after 6 months for calibration purposes, which I now regret, cause it was not needed. But it happened only once in the first year, so hopefully not a big deal.
Initial Battery Stats
Activation Date: May 8, 2024
Screenshot taken: 15 days later
After One Year
May 9, 2025After a full year, the phone has only gone through 106 charge cycles. The battery's original capacity was 4467 mAh, and now it's at 4451 mAh, a loss of just 16 mAh, or ~0.35%. That’s 99.65% of the original capacity still intact!
Quick Math (Just for Fun)
- Original capacity: 4467 mAh
- After 1 year: 4451 mAh
- Loss: 16 mAh in 1 year
- Cycles in 1 year: 106
- Target capacity (80%): 3573.6 mAh
- Required total loss: 893.4 mAh
- Years at current rate: 893.4 ÷ 16 ≈ 55.8 years
So theoretically, at this pace, the battery would take over 55 years to reach 80% capacity.
Realistically Speaking...
I googled and found that lithium batteries degrade faster after a few years, especially after 500+ cycles, or with heat, deep discharges, etc. So while 55 years is fun math, it’s not realistic.
In practice, I’d expect around 5–10% loss per year after a few years, meaning I’ll likely hit 80% in 5–8 years, depending on real world variables.
What’s Next?
If the phone survives and this forum still exists I’ll keep posting updates annually. It’ll be interesting to see how well the iPhone 15 plus battery holds up long term under careful usage.
Placing a google doc link here, cause I won't be able to edit the original post after some time.
Later Updates
Let’s see how far we can really stretch a modern iPhone battery!, backed by real world data.
Last edited:
