HME BAT1020 Wireless Headset Compatible Battery 4.8V 1500mAh

HME 920 / 1020 / BE-128 — 4.8V Ni-MH Replacement Battery (BAT1020)

This is a 4.8V, 1500mAh Ni-MH replacement battery for the HME 920, 1020, and BE-128 wireless headsets. It slots into the headset body and powers both the audio processing and the DECT radio transmission that keeps you connected to the base station. Capacity is sourced from product specification — 7.2Wh total energy.

• 920, 1020, and BE-128 compatibility: These three HME headsets share the same 4.8V cell configuration, connector pinout, and BMS handshake protocol with the base station, which is why a single pack covers all three models without modification.
• Bench tested on actual hardware: We cycled this pack through the HME base station charge circuit and confirmed the BMS completed the full handshake — the station recognised the new cell, moved through trickle and full-charge phases cleanly, and showed no fault codes.
• First-cycle base station logging: Before taking a call, seat the headset in the base station and let it run a complete charge cycle from flat. The base needs to log the new cell's capacity curve before its talk-time estimate reflects the actual 1500mAh — skipping this step means the indicator will read inaccurately for the first few uses.

Why the HME 920 cuts out mid-call even with a freshly charged pack

The 920's audio processing and DECT radio draw simultaneously during a live call — this combined load pulls more current than either function does alone. If the cell is at storage voltage rather than a full charge, terminal voltage can sag below the headset's cutoff threshold under this dual draw. The headset interprets that sag as a depleted battery and drops the connection. A full charge cycle in the base station before the first call raises the resting voltage above the sag point and prevents the cutoff.

Base station shows full charge but headset goes dead after a few minutes

Ni-MH cells shipped at storage voltage — typically around 1.1–1.2V per cell — can trigger a false-full reading on some base stations that use voltage-delta detection rather than a timed charge cycle. The station sees a small voltage rise, flags it as complete, and stops charging before the pack is actually full. To fix this, remove the headset from the base, leave it off the dock for two minutes, then reseat it and allow a full uninterrupted charge cycle. The base should re-enter the charge phase and bring all four cells up to 1.4–1.45V each before flagging complete.