You're staring at a listing for a refurbished iPhone. €450 instead of €800 new. Sounds tempting. Then you spot it: "Battery capacity at least 80%". And suddenly you're wondering if this is a great deal or a trap.
Here's the truth: The refurbished battery is the sticking point where most purchase decisions fall apart. Around 20% of buyers hesitate when buying a refurbished device due to concerns about battery life. Understandable. Nobody wants a smartphone that dies by 3pm.
I took a closer look at battery quality across the major refurbished platforms: refurbed, Back Market, Swappie, rebuy. What do they promise? What do they deliver? And what do these percentages actually mean for your daily life?
What "80% Battery Capacity" Actually Means
80% battery capacity sounds bad at first. But it isn't—if you understand how lithium-ion batteries work.
According to Apple's official specifications, iPhone batteries are designed to retain 80% of their original capacity after 500 to 1,000 complete charge cycles. iPhone 15 and newer manage 1,000 cycles, older models 500 cycles. This isn't a marketing gimmick. It's engineering. You can compare different iPhone models at refurbito to see which sellers offer which battery warranties.
Apple itself only recommends battery replacement when capacity drops below 80%. A refurbished battery at 80% sits exactly at this manufacturer-defined threshold. It isn't "broken" or "bad", but simply reached the point where Apple offers a replacement.
The Chemistry Behind It
Lithium-ion batteries age like humans: Fast at first, then the process slows down. An 80% battery has the mid-life crisis behind it—from now on things get easier. According to Battery University, there are three main factors: depth of discharge, temperature, and charge voltage. A battery that's constantly charged from 0 to 100% ages significantly faster than one that cycles between 25 and 75%.
The interesting bit: Battery capacity doesn't decline linearly. After the initial drop in the first 500 cycles, the curve flattens. A refurbished battery at 80% doesn't degrade twice as fast as one at 100%. It's already past the steepest part of the curve.
What 80% Battery Capacity Means for Your Daily Life
Stiftung Warentest tested 45 refurbished smartphones from nine different sellers—and compared them with barely-used reference devices. The result will surprise you (or not).
The result: Refurbished devices with batteries at the 80% threshold lasted about 2 to 3 hours less than the reference devices.
That sounds like a lot. Sometimes it is. But it depends on your usage patterns.
Scenarios by User Type
Light users (WhatsApp, emails, occasional social media): You check your smartphone at breakfast, during lunch break, and on the couch in the evening. A battery capacity of 80% in refurbished devices easily lasts all day for this user group.
Regular users (2-3 hours of active screen time daily): Gets tight. You'll probably make it through the day, but without any buffer. A charging cable at the office is essential.
Power users (4+ hours screen time, gaming, streaming): You stream Spotify while commuting, scroll Instagram on the train, and check Netflix trailers during lunch. A refurbished battery at 80% is dead by 4pm. A power bank becomes your best friend.
Platform Comparison: Who Offers What?
Standards vary massively. refurbed promises 80% minimum capacity. Swappie raises the bar to 86%. rebuy advertises 36 months warranty—but explicitly excludes batteries.
You can compare all sellers at a glance to find the best option for your needs.
refurbed
Minimum capacity: 80%
refurbed guarantees that all batteries have at least 80% capacity. For some devices, you can add a new battery for an extra fee.
The Extended Warranty from refurbed explicitly covers batteries: If capacity falls below 80% during the warranty period, the battery gets replaced. That matters, because not all sellers do this.
Strength: Clear policies, batteries included in warranty
Back Market
Minimum capacity: 80%
Back Market operates as a marketplace with many sellers. The 80% guarantee applies platform-wide, but actual quality varies depending on the seller.
Example: An iPhone 12 Pro costs €499 at refurbed with 80% battery. On Back Market you'll find the same model for €439—but the seller has only 3.2 stars. Is the risk worth €60 savings?
Strength: Large selection, competitive prices
Swappie
Minimum capacity: 86%
Here's the game changer. Swappie is the only major platform that's raised the standard to 86%. According to Swappie's announcement, they replace batteries with less than 86% capacity as standard during the refurbishment process. Learn more about Swappie and their premium battery option in our detailed seller profile.
Why is this a game changer? Because 6% difference in practice can mean 30-45 minutes more battery life. For a device you use daily for two years, that adds up.
Additionally, Swappie offers a "Premium Battery" option: A brand-new battery with 100% capacity, installed by their in-house technicians. Costs extra, but if battery life matters to you, it's worth it.
Strength: Higher standard (86%), premium option available
rebuy
Minimum capacity: 80%
rebuy advertises an impressive 36-month warranty. Sounds great, right?
Here's the catch: According to the rebuy warranty terms, batteries are explicitly excluded from warranty coverage as "consumable parts". A 36-month warranty that doesn't cover batteries is a problem for many buyers. In our detailed warranty comparison of all sellers you can see exactly who covers what.
Weakness: Battery excluded from warranty
Comparison Table
| Platform | Minimum Capacity | Battery in Warranty? | Premium Option | Warranty Period |
|---|---|---|---|---|
| refurbed | 80% | Yes | Partial | 12+ months |
| Back Market | 80% | Yes | No | 12 months |
| Swappie | 86% | Yes | Yes (100%) | 12 months |
| rebuy | 80% | No | No | 36 months |
| Amazon Renewed | 80% | Varies | No | 12+ months |
Source: Refurb.me Platform Comparison
The Problem with "New" Batteries
Some refurbished devices are advertised with a "new battery". Sounds like a no-brainer, right? Not quite. Because "new" doesn't automatically mean "original".
Original vs. Third-Party Batteries
There's a significant difference between an original Apple battery and a third-party battery. This distinction is especially important with refurbished phone batteries, since most refurbishers use third-party batteries. According to Apple, only genuine batteries are designed to work with iOS battery management features and provide accurate readings for charge level and battery health.
The problem: Only Apple Certified Refurbished and authorized service providers have access to genuine Apple batteries. All other refurbishers typically use third-party batteries.
A Real-World Case Study
In the Apple Community forums, a user reported on their refurbished iPhone 13 purchased from a refurbished seller with a "new battery" showing 100% capacity. Within a month, the battery dropped to under 10% overnight, even in airplane mode. The cause: A swollen battery. The screen had already started separating from the housing.
The good news: The seller repaired the device under the 12-month warranty. The bad news: Non-genuine batteries can cause problems like this.
What to Watch Out For
If maximum battery life matters to you, ask the seller these three questions:
1. Original or third-party? Third-party batteries can cause problems—iOS often doesn't recognize them correctly.
2. Exact capacity? Not "at least 80%". Ask for the exact number. A battery with 81% is different from one with 95%.
3. Does iOS show health correctly? If the warning "Unable to verify this iPhone has a genuine Apple battery" appears, you'll know.
On Apple devices, a non-genuine battery often shows the warning "Unable to verify this iPhone has a genuine Apple battery" under Settings > Battery > Battery Health.
Checklist for the First 48 Hours
You've received your refurbished device. What now? Handtec recommends checking the battery immediately and testing within the return window.
Check Immediately (within the first hour)
1. Check battery health: For iPhones: Settings > Battery > Battery Health. For Android (Samsung): Settings > Battery > More battery settings. Write down the number—you'll need it later as proof.
2. Does the capacity match? Seller promised 85%, display shows 78%? Complain immediately. No discussion.
3. Warning for non-genuine batteries? iOS shows the message "Unable to verify this iPhone has a genuine Apple battery" if a third-party battery was installed. This doesn't automatically disqualify the device—but you should know.
Test in the First Days
Complete two to three full charge cycles: Charge to 100%, use normally until under 20%, repeat. Watch for unusual behavior.
Monitor rapid draining: Does the device lose more than 1-2% per hour without use? That's a red flag.
Check heat generation: Does the device get unusually warm during charging or normal use? Battery problems often show up as overheating.
Document everything: Screenshots of battery status and usage statistics. If you need to return the device, you'll have evidence.
Most sellers have a 14-day return policy. Use this time to really test the battery.
Battery Care for Already-Aged Batteries
Your refurbished device has a battery at 80-85% capacity? With proper care, you can maximize the remaining lifespan.
What the Science Says
According to Battery University, these measures can significantly extend battery life:
Use shallow charge cycles: Keep the battery between 25% and 75%. Full discharges (0%) and constantly charging to 100% stress the battery most. At 50% depth of discharge, a battery achieves 400-600 cycles. At 100% depth of discharge, only about 300.
Avoid heat: Storage at 60°C for three months causes the same damage as one year at 25°C. Don't leave your smartphone in the sun or in a hot car.
Charge slower: Fast chargers are convenient but generate more heat. For battery health, a slower 5W charger overnight is gentler than 20W fast charging.
Enable iOS charge optimization: Apple offers the "Optimized Battery Charging" option under Settings > Battery. The device learns your routine and only charges to 100% shortly before you wake up.
If battery care isn't enough anymore, a professional battery replacement is often cheaper than a new device.
Who Should Actually Get a Refurbished Battery?
I'll be honest: Not everyone.
Refurbished battery quality differs significantly between platforms. As the comparison shows, Swappie offers measurably more with 86% minimum capacity than the standard 80% from other sellers. These 6 percentage points make a noticeable difference in daily use.
Refurbished with 80% battery is ideal for...
Secondary devices: If you need a smartphone for travel or as a backup
Kids and teenagers: First smartphone that's attached to a charger anyway
Home office users: Anyone who's near an outlet all day
Budget-conscious buyers who know what they're getting into
Refurbished with 80% battery is problematic for...
Heavy users: Anyone on their phone 4+ hours a day
Commuters without charging options: Long work days on the go
People who need maximum reliability: Field workers, tradespeople, etc.
The Golden Middle: Swappie with 86% or Premium Option
If battery life matters to you but you still want to buy refurbished, check out Swappie. That extra 6% makes a noticeable difference in practice. Or choose the "new battery" option at refurbed when available.
Conclusion: The Truth About Refurbished Batteries
80% battery capacity isn't a death sentence. But it's also not a minor detail you should ignore.
The refurbished battery determines whether your refurbished smartphone is a bargain or a disappointment. It's the point at which Apple recommends replacement, not the point at which the device becomes unusable. For many users who don't use their smartphone intensively all day, it's perfectly adequate.
But: Not all platforms are equal. Swappie with its 86% minimum standard is measurably ahead. rebuy's 36-month warranty sounds great until you realize batteries are excluded. And "new" batteries are often third-party products that don't have the same quality level as original parts. More details about all aspects of iPhone buying can be found in our complete iPhone buying guide.
My advice: Check battery capacity immediately after receiving the device, test it intensively in the first 14 days, and choose a platform that includes batteries in the warranty. If battery life is particularly important to you, invest the extra €30-80 for a new battery or choose Swappie.
At refurbito, you can compare prices across all platforms and see directly which seller offers the best combination of price and battery quality.
