About this replacement
Thuraya XT / XT Dual — 3.7V Li-ion Replacement Battery (FWD03019)
This 3.7V, 2400mAh Li-ion battery fits the Thuraya XT and XT Dual satellite phones. It replaces OEM part numbers FWD03019 and TH-01-XT5. Both phones share the same battery bay, connector, and BMS handshake protocol.
- XT and XT Dual compatibility: Both models run the same 3.7V power rail, use an identical physical connector, and expect the same BMS communication sequence at startup. One battery covers both handsets.
- Bench tested on actual hardware: We cycled this pack through satellite acquisition on the XT Dual — the BMS handled the antenna deployment plus radio transmit current spike without tripping. Voltage held stable across the draw curve.
- Cold-field pre-warming: Below 0°C, Li-ion internal resistance rises sharply. The satellite acquisition current spike — antenna deployment plus full transmit power — can trip the BMS on a cold cell. In sub-zero conditions, keep the battery in an inner jacket pocket for at least 15 minutes before powering the handset.
BMS cutoff during satellite acquisition on the Thuraya XT Dual
Satellite acquisition pulls the hardest current draw the XT Dual produces — antenna deployment and the radio searching at maximum power hit simultaneously. An aged or cold cell can't hold voltage across that spike, so the BMS trips to protect the cell and the phone shuts off before a lock is achieved. This isn't a phone fault. It's the BMS doing its job on a cell that can no longer deliver the instantaneous current the acquisition sequence demands. A fresh cell at or above 3.7V resting voltage will clear this.
Charger refusing to accept the pack after weeks of storage
Li-ion cells stored partially discharged will self-discharge below the charger's acceptance threshold — typically around 2.5V — over several weeks. When the charger sees a cell voltage that low, it reads the pack as faulty and refuses to initiate a charge cycle. Some chargers have a recovery or trickle mode; activate it, or apply a brief charge via a compatible USB power bank directly to the phone to nudge the cell above 2.9V. Once the cell clears that threshold, a standard charger will accept it normally.