About this replacement
Apple MacBook Pro 15" A1286 — 10.8V Li-Polymer Replacement Battery (A1281)
This is a 10.8V, 4600mAh (49.68Wh) lithium-polymer battery for the Apple MacBook Pro 15" A1286, including the Aluminum Unibody 2008 models. It fits the MB470 and MB772 chassis variants listed under OEM part numbers A1281 and MB772LL/A. Install it when the original cell no longer holds a charge or macOS flags battery health as degraded.
- A1286 Aluminum Unibody compatibility: These 2008-era 15" MacBook Pro units share the same 10.8V power rail, the same physical connector, and the same BMS handshake profile — which is why all MB470 and MB772 sub-variants accept the same replacement cell.
- Bench tested on actual hardware: We ran this cell on an A1286 chassis and confirmed the BMS completed a full charge cycle without tripping overcharge protection. macOS System Information reported correct voltage and Wh values after the first complete cycle.
- Post-install calibration for A1286: After fitting this cell, run the MacBook until it reaches hibernate cutoff — do not interrupt — then charge uninterrupted to 100%. This forces the onboard fuel gauge IC to re-learn the new cell's actual capacity and clears the inaccurate health warning that appears after every cell swap.
MacBook Pro A1286 shutting down at 20–30% charge remaining after battery swap
This is a voltage cliff problem, not a capacity defect. Under combined CPU and display load, the new cell's voltage drops faster than the uncalibrated fuel gauge expects. macOS reads a falsely inflated state-of-charge right up until the cell voltage falls below the BMS cutoff threshold — then the system shuts off instantly. Run two full discharge-to-hibernate cycles followed by uninterrupted charges to 100%. After the second cycle, the fuel gauge IC recalibrates against the real voltage curve of the new cell and the premature shutdowns stop.
macOS reporting wrong Wh rating in System Information after fitting this cell
System Information pulls Wh data from EEPROM values stored in the battery's onboard controller — not from a live chemistry measurement. The old cell's EEPROM data may still be cached, or the new cell's rated Wh differs slightly from the figure Apple's firmware expects. This is a firmware reconciliation issue and does not affect how the cell charges or discharges. Run the calibration cycle described above; after one full discharge and recharge, the reported Wh value should align to 49.68Wh.