- Stock: 43
- Brand: iParts4u
- Compatible with: iPh 12/12P
- SKU: 641243053226
Restore full battery life to the iPhone 12 and iPhone 12 Pro with this genuine Apple Battery Replacement, Apple service part 661-17920, supplied in reclaimed condition and certified at 100% Battery Health. Professionally removed from a working donor device, fully cleaned, voltage-tested and capacity-verified by our QA team, the cell delivers Apple's original 2815 mAh capacity, fast charging and MagSafe wireless charging support — the same lithium-ion chemistry and safety circuitry fitted at the factory.
Because the underlying cell is genuine Apple, the iPhone retains accurate iOS power management behaviour, native fast-charge negotiation up to 20W and full MagSafe wireless charging speed. Aftermarket alternatives often misreport state-of-charge, fail to negotiate fast charging, or trigger persistent system warnings — making genuine reclaimed the right choice for any iPhone 12 or 12 Pro repair where the customer expects factory-spec battery performance.
Common Faults Resolved
- Battery draining rapidly under normal use
- Sudden shutdowns at 20–40% remaining charge
- Battery Health below 80% in iOS Settings
- "Service" battery message in Settings → Battery → Battery Health
- Performance throttling flagged by iOS due to degraded battery
- Phone running hot during normal use or charging
- Battery swelling causing screen lift or chassis distortion
- Failed prior repair using a non-genuine or low-quality replacement cell
Key Features
- Genuine Apple cell: Apple service part 661-17920, reclaimed from a working donor device
- 100% Battery Health certified: capacity, cycle count and voltage verified before dispatch
- 2815 mAh capacity: Apple-spec, identical to the factory-fitted cell
- Fast charging supported: up to 20W via USB-C Power Delivery, full MagSafe wireless charging speed
- Integrated safety circuitry: over-current, over-discharge and thermal protection
- QA-tested: every cell is bench-tested for capacity, voltage stability and connector function before dispatch
- Trade dispatch: in stock from the UK with fast trade dispatch
Compatible With
- iPhone 12 — A2172, A2402, A2403, A2404
- iPhone 12 Pro — A2341, A2406, A2407, A2408
Not Compatible With
- iPhone 12 mini (different part number, smaller capacity cell)
- iPhone 12 Pro Max (different part number, larger 3687 mAh cell — see part 661-18428)
What's Included
- 1 x Genuine reclaimed iPhone 12 / 12 Pro Battery (Apple part 661-17920, 2815 mAh, 100% Battery Health certified)
Important Notes
- "Important Battery Message" warning: on iOS 14.7 and later, fitting any battery that has not been factory-paired by Apple will display an "Important Battery Message" notification at the lock screen for 4 days, then move to Settings → Battery → Battery Health & Charging. This applies to all non-paired battery replacements, including genuine reclaimed cells. The notification is informational only and does not affect charging or performance.
- Battery Health percentage may display as "Unknown". Apple's iOS pairs the battery management system (BMS) chip to the original logic board. To retain the full Battery Health percentage display, the original BMS chip must be transferred from the customer's old battery onto the reclaimed cell by an experienced microsolder technician. Without this transfer, Battery Health will read "Unknown" but the cell will still charge and discharge normally.
- Run Apple Repair Assistant after fitment (iOS 17 and later): navigate to Settings → General → About → Parts & Service History → Restart & Finish Repair and follow the on-screen prompts to attempt automatic pairing.
- Replace battery adhesive during fitment for a secure long-term bond. Use moderate heat to soften old adhesive for safe removal, and clean all residue from the chassis before fitting the new cell. Never use heat on a swollen battery — apply isopropyl alcohol around the edges and lift gently.
- Calibration: after fitment, fully discharge the battery to below 10%, then charge uninterrupted to 100% to allow iOS to calibrate state-of-charge reporting accurately.
- Bench-test before final fitment: connect the battery to the mainboard and verify clean boot, normal voltage at rest (3.7–4.2V), charging behaviour and absence of fault codes before sealing the device.
- Installation should be carried out by a qualified technician using suitable heat, separation, isopropyl alcohol and ESD-safe tools to avoid damage to the chassis, flex cables or logic board.
Frequently Asked Questions
What does "100% Battery Health" mean for a reclaimed battery?
Every battery in this listing has been individually tested for capacity, cycle count and voltage stability. Cells are graded against Apple's original specification and only those reading 100% maximum capacity at the time of testing pass our QA. As with any lithium-ion battery, capacity will gradually reduce with use over time — but you start the new battery's life at full factory capacity.
Will my iPhone show a "Service" or "Important Battery Message" after fitment?
Yes — on iOS 14.7 and later, any battery replacement that has not been factory-paired by Apple will display an "Important Battery Message" notification. This applies to all replacement batteries, including genuine reclaimed cells. The message is informational and does not affect charging, performance or longevity. It can only be removed by microsolder-transferring the original BMS chip onto the new battery, or by Apple-authorised pairing.
Why might Battery Health show as "Unknown"?
iOS reads Battery Health from the battery's BMS chip, which Apple pairs to the original logic board at the factory. When a non-paired battery is fitted, iOS cannot read the Battery Health value and displays "Unknown" instead. The cell still charges and discharges normally — only the percentage display is affected. Microsolder-transferring the BMS chip from the old battery onto the new cell restores full Battery Health reporting.
Is this genuine Apple or aftermarket?
This is a genuine Apple battery (Apple service part 661-17920) reclaimed from a working donor iPhone. It is not an aftermarket or third-party manufactured cell. Reclaimed simply means the cell has been professionally removed from a previous device, cleaned, tested, and certified before being supplied for repair use.
What tools do I need to fit this battery?
iPhone 12 / 12 Pro battery replacement requires a pentalobe screwdriver, tri-point Y000 driver, suction handle, plastic spudger, plastic opening picks, isopropyl alcohol and replacement battery adhesive strips. iParts4U stock all the relevant repair tools — search our site for the iPhone 12 toolkit.
How long does the install take?
For an experienced technician, an iPhone 12 / 12 Pro battery replacement takes approximately 30–45 minutes from screen separation to final reassembly. Allow longer for first-time installers and for any microsolder BMS transfer work.
Do you offer technical support?
We offer all customers technical support Monday to Friday, 9am–5pm, for both trained repairers and first-timers. You're welcome to call us to discuss any technical issues you may be facing during the repair.
Will fitting this battery void my Apple warranty?
Apple warranty on most iPhone 12 / 12 Pro devices has expired (the model launched in October 2020). Where any extended warranty or AppleCare cover remains active, fitting a non-Apple-authorised battery may void it. Customers should check their warranty status before proceeding with a third-party repair.
For our complete range of iPhone 12 components, visit our iPhone 12 replacement parts and iPhone 12 Pro replacement parts categories. To browse our full iPhone battery range, visit our iPhone battery category.
This is a genuine Apple component that has been professionally removed from a donor device and fully tested prior to dispatch. It is supplied in full working condition and is intended for use by qualified repair professionals and trade technicians only.
| Specifications | |
| Capacity | 2815 mAh |
| Cell Type | Li-iON |
| Source | Reclaimed |
| Product Type | |
| Product Type | Battery |
| Warranty | |
| Warranty Length | 90 Days |
| Cycle Life | 500-800 |
