Optex iVision-L Wireless Intercom Compatible Battery 3.6V 700mAh

Optex Wireless Two-Way Intercom System / iVision-L — 3.6V Ni-MH Replacement Battery

This is a 3.6V, 700mAh Ni-MH rechargeable battery for the Optex Wireless Two-Way Intercom System and iVision-L. It slots into the intercom handset or base unit and restores two-way voice communication between stations. Use the capacity figure from the product data — 700mAh — as your reference when comparing to the original cell.

• Wireless Two-Way Intercom / iVision-L fit: Both models share the same 3.6V Ni-MH cell format, connector orientation, and BMS handshake voltage. One battery covers either unit without modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the intercom platform. The BMS accepted the cell cleanly, voltage held at 3.6V nominal across the communication circuit, and no false low-battery flags triggered during the test cycle.
• Ni-MH reconditioning on the Optex platform: Ni-MH cells in these intercom units are prone to voltage depression if they sit discharged for extended periods. After fitting a replacement, run at least two full charge-discharge cycles before judging capacity — the cell's internal resistance drops measurably after the second cycle on this platform.

Why the Optex intercom drops to low-battery warning immediately after a fresh charge

The Optex intercom reads battery state using a voltage-threshold indicator, not a fuel gauge IC. A new or recently replaced Ni-MH cell can sit at a suppressed resting voltage — typically below 3.4V — if it has not been cycled. The unit reads that suppressed voltage and flags low battery even when the cell is physically full. Running one complete charge-discharge cycle raises the resting voltage above the platform's detection threshold and clears the false warning.

Intercom station goes silent after battery swap — no audio, no response on press

When the cell is swapped while the unit retains residual power, the firmware can lose its session state and stop polling the RF link. The station appears powered but produces no audio and ignores button presses from the paired unit. Remove the battery, wait 30 seconds to let the capacitors fully drain, then reinsert and power on. This forces a clean firmware restart and re-establishes the RF handshake at the correct 3.6V rail.