Tele2 i-HEAR Cordless Phone Compatible Battery 3.6V 700mAh

Tele2 i-HEAR — 3.6V Ni-MH Replacement Battery

This is a 3.6V, 700mAh Ni-MH replacement battery for the Tele2 i-HEAR cordless phone handset. It fits directly into the handset compartment and restores power to the handset when the original cell has degraded or failed. Voltage and pack size match the original specification.

• Tele2 i-HEAR handset fit: The i-HEAR uses a 3.6V single-cell Ni-MH pack at a compact 43 × 31 × 8mm footprint. This battery matches that form factor and voltage rail, so the handset charges and operates normally on the base station.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on a cordless phone test rig. The cell accepted a full charge from a standard DECT base station circuit and held voltage within expected range across standby and active RF transmit draw.
• First-charge protocol for Ni-MH handsets: After installing, seat the handset in the base for a full 16-hour charge before first use. Ni-MH cordless phone cells ship in a partial-discharge state and need a slow, full first charge to reach rated capacity — skipping this step will result in noticeably shorter talk time from day one.

Talk time shorter than original battery after replacement

Ni-MH cells do not deliver full rated capacity on the first cycle. The electrochemical structure needs three to five full charge-discharge cycles before the cell reaches its nominal 700mAh. If talk time feels short after day one, this is expected behaviour — not a fault. Run the handset to low battery, return it to the base for a full charge, and repeat for a few cycles. Capacity will stabilise by cycle four or five.

Base station not charging after battery swap

DECT base chargers use a delta-V detection method to sense that charging has started. A Ni-MH cell that has sat in storage at very low voltage may not show the initial voltage rise the base circuit expects, causing the charge indicator to stay off or show an error. Remove the handset, leave it out of the base for 30 seconds, then reseat it firmly — full contact on both charge pins is required. If the base still shows no charge activity, a brief trickle charge from an external Ni-MH charger at 70mA for one hour will lift the cell voltage above the acceptance threshold, after which the base station will take over normally.