JNC SSF-H5 Sansa Fuze+ Replacement Battery 3.7V 950mAh

JNC SanDisk Sansa Fuze+ SSF-H5 — 3.7V Li-Polymer Replacement Battery (P50206)

This 3.7V, 950mAh Li-Polymer cell replaces the original battery in the SanDisk Sansa Fuze+ portable media player. It fits the SSF-H5 model and restores power to a player that no longer holds a charge or fails to start. Capacity matches OEM spec at 950mAh (3.52Wh).

• Sansa Fuze+ SSF-H5 fit: The Fuze+ uses a slim Li-Polymer pouch cell with a proprietary connector and a battery management circuit that checks voltage on insertion. This cell matches the physical dimensions (61.19 × 4.41 × 2.54mm), connector pinout, and voltage profile the BMS expects.
• Bench tested on actual hardware: We ran this cell in an SSF-H5 unit and confirmed the BMS accepted the cell without error, the fuel gauge initialised correctly, and the player cycled through charge and discharge without thermal events.
• Post-swap charge protocol for the Fuze+: After fitting a new cell, connect the player to a USB charger and leave it for at least 30 minutes before pressing power. The Fuze+ enters a low-voltage lockout state when the cell voltage drops below roughly 3.0V, and the player will not respond to the power button until the charger has pushed the cell above that threshold.

Battery percentage jumping on the Fuze+ after a cell swap

The Sansa Fuze+ uses a voltage-threshold method to estimate charge level — it maps cell voltage to a percentage rather than tracking coulombs. A fresh cell has a slightly different discharge curve than an aged cell, so the indicator recalibrates over the first few cycles. Expect the percentage to jump or drop suddenly during the first two to three charge cycles. After that, let the player run down to the low-battery warning and charge fully — the indicator will stabilise at that point.

Playback cutting out before the battery indicator shows empty

The audio amplifier in the Fuze+ draws a brief current spike when driving headphones at higher volumes. Near the end of a discharge cycle, cell voltage sags under that load and drops below the amplifier's minimum rail voltage — the player cuts audio or shuts down even though the indicator still shows a few percent remaining. This is a voltage sag issue, not a capacity issue. Keeping playback volume below 80% reduces the spike and extends usable discharge. If cutouts happen frequently at mid-charge, the cell may already be in poor condition and replacement is the next step.