Humantechnik InfraLight DIR Replacement Battery 2.4V 80mAh

Humantechnik InfraLight DIR / InfraLight II Series — 2.4V Ni-MH Replacement Battery

This is a 2.4V, 80mAh Ni-MH replacement cell for the Humantechnik InfraLight DIR wireless headset and related models in the InfraLight range. It restores cordless audio operation in hearing assistance and communication headsets that have lost the ability to hold a charge. Fits the InfraLight DIR, InfraLight II, InfraLight II LR, and LPU-1 among others.

• InfraLight series compatibility: These models share the same 2.4V cell configuration, physical housing dimensions (33.90 × 20.00 × 10.50mm), and base station charging interface. Swapping across the range works because the charge management is handled by the base unit, not an on-cell BMS.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the bench. The base station accepted the new cell without error and brought it to full charge without triggering a fault state. Discharge curve tracked consistently with the 80mAh rating across multiple cycles.
• First-use charging on InfraLight headsets: Place the headset in the base station and let it complete one full uninterrupted charge cycle before taking a call. DECT headsets log the new cell during this first cycle — skipping it causes the talk-time indicator to read inaccurately until the base recalibrates.

Base station showing full charge but headset cuts off after short use

A freshly installed cell arrives at storage voltage, typically around 2.2V or lower. The base station may interpret this as a charged cell after a short top-up and display a full indicator before the cell has actually completed a proper charge cycle. The headset then cuts off quickly because available capacity is a fraction of the rated 80mAh. Let the headset sit in the base undisturbed for a full charge cycle — usually several hours — before use.

Headset cutting out mid-call on a replacement cell

The InfraLight headset draws current from two loads simultaneously: the audio driver and the 2.4GHz radio transmitter. At 80mAh, the cell operates at a low absolute capacity, so combined draw causes voltage to sag faster than either load alone would. If cut-outs happen with a new cell, the cell likely has not completed its first conditioning cycle. Run three to five full charge-discharge cycles through normal use — talk time improves as the cell reaches its rated capacity. If cut-outs continue after five cycles, check that the cell contacts in the headset housing are clean and making firm contact.