Comrex Access Portable2 7.4V Li-ion Replacement Battery 10400mAh

Comrex Access Portable2 — 7.4V Li-ion Replacement Battery

This 7.4V 10400mAh (76.96Wh) Li-ion battery is a direct replacement for the Comrex Access Portable2 portable audio codec. The Access Portable2 is a professional broadcast device used by journalists and field engineers for remote live audio transmission. This cell keeps the unit running during extended fieldwork where AC power is not available.

• Access Portable2 platform fit: The Access Portable2 draws a steady current load to maintain its codec processing, DSP, and network transmission simultaneously. This cell matches the 7.4V rail the unit expects and delivers 10400mAh capacity to sustain that combined draw across extended remote sessions.
• Bench tested on actual hardware: We ran this cell under a simulated codec and network transmission load. The BMS held voltage within the Access Portable2's operating threshold throughout the discharge cycle without triggering a low-voltage cutoff prematurely.
• Field rotation discipline: The Access Portable2 does not always drain a battery fully before powering off — repeated shallow cycles can compress effective capacity over time. Cycle this cell to near-full depletion once every several sessions to keep the BMS calibration accurate.

Why the Access Portable2 shows a battery warning with a freshly installed cell

The Access Portable2 reads battery state based on voltage thresholds mapped to its internal firmware. A new cell sometimes presents a resting voltage that sits at a threshold boundary, causing the unit to flag a low-battery condition even though the cell is not depleted. Running one full charge cycle through the device before field deployment lets the firmware map the new cell's discharge curve correctly. After that initial cycle, warning behaviour typically resolves.

Access Portable2 powering off unexpectedly mid-transmission

The codec, network modem, and audio DSP all pull current simultaneously during a live transmission. That combined draw creates a brief voltage sag that the BMS can read as a fault if the cell is partially discharged. The Access Portable2 will shut down to protect the circuit rather than continue on a sagging rail. If this happens, check resting voltage with a multimeter — if it reads below 7.0V under no load, the cell needs a full recharge before the next session.