About this replacement
EXFO OX1 Optical Explorer — 3.7V Li-Polymer Replacement Battery (E018)
This 3.7V 6500mAh (24.05Wh) Li-Polymer pack replaces the OEM battery in the EXFO OX1, OX1 Optical Fiber Multimeter, and OX1 Optical Explorer. It fits anywhere the E018 or GP-3150 part number is called out. The OX1 is a field-portable optical power meter and light source used for fiber optic installation and maintenance.
- OX1 platform fit: All OX1 variants share the same 3.7V cell format, connector pinout, and BMS handshake protocol. Swapping between OX1 Multimeter and OX1 Explorer units requires no adapter or firmware change — the same pack seats and communicates identically across the platform.
- Bench tested on actual hardware: We cycled this pack through the OX1's power-up sequence, including optical source activation and power meter initialisation. The BMS held voltage within spec across both high-draw probe events and sustained steady-state logging draws without triggering a cutoff.
- Post-install calibration cycle: After fitting this pack, run a full calibration cycle through the OX1 instrument menu before heading into the field. The instrument maps battery state during calibration — skipping this step causes premature low-battery warnings to appear during your first measurement session.
BMS lockout after the OX1 sat unused in a carry case for months
Li-Polymer cells self-discharge slowly during storage. If the OX1 sat in a case long enough, the pack voltage can drop below 3.0V — the threshold where most BMS circuits latch into deep-discharge lockout and refuse to accept a charge. The instrument won't power on, and the charger shows no activity. To recover, apply a slow, low-current charge directly to the pack for 10–15 minutes using a compatible Li-Po charger set below 0.1C, then reconnect and retry the standard charge cycle. If the cell recovers above 3.2V, normal charging resumes.
OX1 display shows inconsistent battery percentage at every reboot
When a new cell is installed, the OX1's state-of-charge indicator hasn't yet mapped the voltage curve of the replacement pack — it's still referencing thresholds calibrated to the old, degraded cell. This causes the percentage readout to jump or reset differently on each power cycle. The fix is straightforward: run two full charge-to-discharge cycles through normal field use, then charge fully to 4.2V before the third session. After that, the indicator stabilises and tracks accurately.