About this replacement
Apple MacBook Pro 13" 2015 Retina — 11.43V Li-Polymer Replacement Battery (A1582)
This is an 11.43V, 6500mAh lithium-polymer battery for the Apple MacBook Pro 13" 2015 Retina. It fits models MF841LL/A, MF839LL/A, and MGX82CH/A, among others. OEM part numbers A1582 and 020-00009 confirm fitment.
- MF839LL/A and MF841LL/A platform: These two models share the same battery bay geometry, connector pinout, and BMS handshake protocol. The A1582 cell fits both without modification to the cable or adhesive strip layout.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a 2015 Retina unit. The BMS accepted the cell without fault flags, SMC communication stayed stable, and the charge controller stepped through its full 11.43V profile without throttling.
- First-cycle reset after installation: After fitting, run the MacBook down to automatic hibernate cutoff — not sleep, full shutdown — then charge uninterrupted to 100%. This forces the SMC to complete one full learn cycle against the new cell and clears the inaccurate health warning that shows up after every cell swap on this platform.
Why macOS reports "Service Battery" immediately after a new A1582 install
macOS reads battery health from EEPROM data stored by the System Management Controller, not from live voltage alone. When you swap the cell, the SMC still holds cycle count and health records from the old battery. Until the SMC runs a full learn cycle with the new cell, it compares live readings against stale data and flags a mismatch. One full discharge-to-hibernate followed by an uninterrupted charge to 100% rewrites that baseline. After two to three cycles the health status updates and the warning clears.
MacBook shuts down at 20–30% battery shown on the menu bar
This happens when the fuel gauge IC has not yet calibrated against the new cell's actual voltage curve. The IC predicts empty at the wrong voltage point and triggers shutdown before the cell is truly depleted. It is not a cell fault — it is a calibration gap between the old cell's discharge profile and the new one. Run two full discharge-to-hibernate cycles, charging fully between each, and the fuel gauge will anchor its cutoff to the correct 3.0V-per-cell floor.