Sena 10U Replacement Battery YT501542P 3.7V 250mAh

Sena 10U — 3.7V Li-Polymer Replacement Battery (YT501542P)

This 3.7V, 250mAh lithium-polymer cell replaces the OEM battery in the Sena 10U motorcycle Bluetooth headset. It fits directly into the 10U's compact housing and restores wireless audio, intercom, and call functionality. Capacity listed here is sourced from the product data — 0.93Wh total energy.

• Sena 10U platform fit: The 10U integrates directly into certain helmet speaker cavities, leaving almost no room for a thicker cell. This 42.50 × 12.50 × 5.15mm pack matches the OEM footprint so the housing closes flush and the connector seats without force.
• Bench tested on actual hardware: We cycled this cell through the 10U's combined Bluetooth audio and intercom radio draw. The BMS held voltage above the 3.0V cutoff threshold through multiple discharge cycles without triggering premature shutoff.
• First charge after fitting: Seat the 10U in its mount and charge to full before using intercom or audio — the headset's firmware logs battery state during the first full charge cycle, and skipping this step causes the charge indicator to read inaccurately for the first several uses.

Why the 10U cuts out mid-call on a new battery

The 10U runs Bluetooth audio and its intercom radio simultaneously during calls. That combined draw creates brief current spikes that can pull cell voltage below the BMS protection threshold on a pack that hasn't completed a conditioning cycle. The BMS reads this sag as a low-cell event and shuts the headset down, even if the indicator showed charge remaining. Running two or three full charge-discharge cycles brings the cell to stable operating voltage and reduces sag under combined load.

Talk time shorter than rated on the first few uses

Li-polymer cells ship at storage voltage — typically around 3.7V — not at full capacity. On the first use, the 10U's firmware may display a full charge while the cell hasn't reached its actual capacity ceiling. Talk time improves noticeably between cycles two and five as the cell reaches its rated 250mAh. Charge fully, use until the headset powers down on its own, then recharge — repeat three times to complete conditioning.