Apple iPOD Nano 2GB Replacement Battery 3.7V 400mAh

Apple iPod Nano Series — 3.7V Li-Polymer Replacement Battery (616-0283)

This is a 3.7V, 400mAh lithium-polymer cell for the Apple iPod Nano 2GB, 4GB, MA004LL/A, and MA099LL/A. It replaces OEM part numbers 616-0283, 616-0223, and 616-0224. Fits the slim first-generation Nano form factor where the original pouch cell has degraded or failed entirely.

• Nano 2GB and 4GB compatibility: These models share the same physical cell dimensions (35.80 × 23.20 × 4.80mm), connector pinout, and BMS voltage thresholds. One cell covers both capacity variants because Apple used the same battery housing across the range.
• Bench tested on actual hardware: We ran this cell through charge cycles on a Nano MA004LL/A. The BMS accepted charge current without triggering overcurrent protection, and the device reported voltage correctly through the dock connector.
• Post-swap trickle charge requirement: After fitting this cell, connect the Nano to a charger for at least 30 minutes before attempting to power on. If the replacement cell shipped at low voltage, the device enters deep discharge protection and will not boot from a single button press — the charger must bring the cell above the BMS wake threshold first.

Battery percentage jumping after a cell swap on the iPod Nano

The Nano reads battery level by mapping open-circuit voltage against a lookup table calibrated to the original cell's discharge curve. A new lithium-polymer cell has a slightly different voltage profile at mid-charge states, so the percentage indicator can jump — showing 80%, then 60%, then back to 75% within minutes. This is not a fault in the replacement cell. Run two full charge and discharge cycles and the indicator will settle as the device recalibrates its voltage thresholds against the new cell's actual curve.

Playback cutting out before the battery indicator shows empty

As a lithium-polymer cell ages, its internal resistance rises. When the audio amplifier draws current during playback — particularly at higher volumes — the voltage drop across that internal resistance can pull the cell voltage below the BMS cutoff threshold before the displayed percentage reaches zero. The device shuts down to protect the cell, even though the indicator still showed charge remaining. If this happens on a new replacement cell, check that the connector is fully seated; a partial connection adds resistance and triggers the same early cutoff. A secure connection keeps the voltage at the BMS input above 3.0V under load.