Ascom Adesso Cordless Phone Replacement Battery 3.6V 600mAh

Ascom Adesso — 3.6V Ni-MH Replacement Battery

This is a 3.6V 600mAh Ni-MH battery for the Ascom Adesso cordless DECT handset. It replaces the original pack when the handset no longer holds a charge or drops calls due to low voltage. Dimensions are 30.30 × 42.60 × 14.30mm — confirm these match your existing pack before ordering.

• Ascom Adesso handset fit: The Adesso uses a compact 3.6V three-cell Ni-MH configuration. This battery matches that voltage rail and physical footprint, so the contacts seat correctly in the handset bay.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on a Ni-MH test bench. The cells reached rated capacity by cycle four and the voltage curve stayed flat through the mid-discharge band.
• First-charge protocol for Ni-MH handsets: Place the Adesso handset in its base station immediately after installing this battery and leave it for a full 16 hours before first use. Ni-MH cells shipped in storage discharge arrive partially depleted — a slow first charge lets all three cells balance and reach rated capacity together.

Talk time shorter than the original battery after replacement

Ni-MH cells do not deliver full rated capacity on the first cycle. Fresh cells need three to five full charge-discharge cycles before the chemical structure inside each cell stabilises. During this break-in period the pack may read low voltage earlier than expected and trigger the handset's low-battery warning prematurely. Run three full cycles — charge to completion in the base, use the handset until the low-battery alert sounds, then return it to the base — before judging talk time.

Base station showing no-charge or error light after battery swap

Ascom bases check for a minimum voltage threshold before starting the charge cycle. A Ni-MH pack that has been sitting in storage can drop below 3.0V total — low enough that the base rejects it and shows a fault light instead of a charge indicator. To recover the pack, apply a short trickle charge using a standalone Ni-MH charger at 60–100mA for 30 minutes to bring the voltage above the base's acceptance floor, then seat the handset in the Adesso base as normal. The base should then recognise the pack and switch to its standard charge current.