About this replacement
Apple iPod Classic 3rd / 4th Generation — 3.7V Li-Polymer Replacement Battery (AE505060)
This 3.7V, 2000mAh Li-Polymer cell replaces part number AE505060 in the Apple iPod Classic 3rd and 4th Generation (A1040, A1059). It restores charge capacity to the internal storage-based portable media player. Dimensions are 61.00 × 49.70 × 5.10mm — measure your existing cell before ordering if the device has been serviced before.
- A1040 and A1059 compatibility: Both the 3rd and 4th generation iPod Classic share the same battery bay dimensions, connector pinout, and charge-management IC. One cell fits both without modification.
- Bench tested on actual hardware: We ran the AE505060 through charge cycles on both A1040 and A1059 units. The BMS accepted charge handshake correctly on first connect, with no false-full cutoff or charge loop detected.
- First charge after cell swap: Connect the iPod to a wall adapter — not a computer USB port — immediately after installing. Computer USB ports on older machines may deliver insufficient current if the cell sits at a low state of charge, stalling the charge IC before it reaches normal charging current.
Battery percentage jumping after cell swap in iPod Classic
After a cell replacement, the iPod's charge indicator reads the new cell's voltage against lookup tables calibrated to the old, degraded cell. The result is erratic percentage jumps — 80% one moment, 40% the next. This is not a fault in the replacement cell. Run two full charge and discharge cycles through normal playback and the voltage-threshold indicator will recalibrate to the new cell's discharge curve. After two cycles, readings stabilise and track accurately.
Playback cutting out before the battery indicator shows empty
The iPod Classic's audio amplifier draws a current spike during playback that the battery gauge does not account for in real time. As cell voltage drops toward the low end of discharge — around 3.5V — the amplifier's instantaneous draw pulls the rail below the BMS cutoff threshold before the indicator reaches zero. This is common in aged cells where internal resistance has risen, but can also appear briefly in new cells during the first discharge cycle. If it occurs after the second full cycle, check that the dock connector is clean and making full contact on charge.