Telekom Speedphone 701 Replacement Battery 3.7V 1300mAh

Telekom Speedphone 701 — 3.7V Li-ion Replacement Battery

This 3.7V 1300mAh (4.81Wh) lithium-ion battery replaces the original cell in the Telekom Speedphone 701 cordless DECT handset. It fits the handset directly, restoring normal operation when the original battery no longer holds a charge. Dimensions are 60.00 × 38.12 × 5.75mm — confirm these match your existing cell before installing.

• Speedphone 701 handset fit: The Speedphone 701 uses a slim single-cell Li-ion pack at 3.7V nominal. This cell matches that voltage rail and physical footprint, so the handset's power management circuit recognises it without modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the bench and monitored the protection circuit. The BMS triggered correctly at low-voltage cutoff and did not flag an error during the charge phase.
• First charge after installation: Place the handset in the base station immediately after fitting this battery and leave it for a full uninterrupted charge cycle before making any calls. Li-ion cells shipped in partial-charge storage state benefit from one complete charge before the handset's fuel gauge calibrates correctly.

Talk time shorter than expected after fitting a new cell

A new Li-ion cell shipped from storage often arrives at around 40–60% state of charge. The handset's internal fuel gauge reads from this partial baseline, so its talk time estimate starts low and stays inaccurate until the gauge resets. Run two full charge-to-cutoff cycles — charge in base until the charge light goes solid, then use the handset until it signals low battery. After two cycles, the gauge recalibrates to the full 1300mAh capacity and talk time estimates stabilise.

Handset loses DECT pairing after battery replacement

Removing the old battery cuts all power to the handset, which can clear the DECT registration stored in volatile memory on some Speedphone models. The handset then boots as unregistered and cannot connect to the base. To re-pair, press and hold the registration button on the base station until the base enters pairing mode, then initiate registration from the handset menu. The process takes under two minutes and does not affect phonebook entries stored on the base.