Rio Nitrus MP3 Player Replacement Battery TY02 3.7V 600mAh

Rio Nitrus MP3 Player — 3.7V Li-ion Replacement Battery (TY02)

This 3.7V 600mAh Li-ion cell replaces the original TY02 battery in the Rio Nitrus portable digital audio player. It fits the Nitrus directly and restores power to units where the original cell has degraded or failed to hold a charge. Voltage and capacity match the OEM specification.

• Rio Nitrus compatibility: The Nitrus uses a single-cell Li-ion pack at 3.7V nominal. The TY02 and alternate part DY002 share the same cell format, voltage rail, and connector pinout — there is no model variation that changes the battery interface on this device.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the Nitrus platform. The BMS accepted charge current normally from the device's internal charging circuit and held the cutoff voltage within expected range at end of discharge.
• Post-install charge requirement: After fitting a new cell, connect the Nitrus to its charger before powering it on. Cells shipped in storage state may sit below the threshold the device needs to boot, and skipping this step can leave the player unresponsive at the power button.

Battery percentage jumping after cell swap on the Nitrus

The Nitrus uses a voltage-threshold method to estimate charge level — it does not have a fuel gauge IC that tracks coulombs. After fitting a new cell, the firmware's internal reference points are misaligned with the new cell's discharge curve. This causes the indicator to jump or read incorrectly for the first several cycles. Run two or three full charge and discharge cycles and the reading will stabilise as the firmware recalibrates to the new cell's voltage behaviour.

Playback cutting out before the battery indicator shows empty

At the tail end of a Li-ion discharge curve, cell voltage drops sharply. The audio amplifier in the Nitrus draws enough current at that point to pull the voltage below the BMS cutoff threshold before the battery indicator has caught up with the actual state of charge. The device shuts down to protect the cell — not because of a fault. If this happens repeatedly, check that the cell is completing full charge cycles and that the charger connection is clean and seated. A fully charged cell should read 4.2V at the terminals.