Olympus EYE-TREK Compatible Battery 7.4V 2600mAh Li-ion

Olympus EYE-TREK — 7.4V Li-ion Replacement Battery

This 7.4V, 2600mAh (19.24Wh) lithium-ion cell is a direct replacement for the Olympus EYE-TREK head-mounted wearable camera. The EYE-TREK records hands-free photo and video, and the original battery degrades noticeably after repeated charge cycles. This replacement restores full operating voltage to the device.

• EYE-TREK platform fit: The EYE-TREK uses a 7.4V two-cell Li-ion pack with a specific connector and BMS communication line. Any replacement must match both voltage and physical format — 70.80 x 38.50 x 23.20mm — to seat correctly and allow the camera body to read state-of-charge accurately.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the EYE-TREK platform. The BMS accepted the cell on first install, reported state-of-charge without error flags, and held voltage within the expected discharge curve across the full cycle.
• First-cycle calibration on the EYE-TREK: Run one complete charge cycle through the OEM charger or camera body before heavy recording sessions. The EYE-TREK BMS maps its battery-remaining indicator to a discharge curve it calibrates on that first cycle — skipping it causes inaccurate percentage readings throughout the battery's life.

Why the EYE-TREK shows a dead battery indicator on a partially charged replacement cell

The EYE-TREK reads remaining charge by mapping terminal voltage to a pre-loaded discharge curve stored in the BMS. A new cell with no calibration history can sit at 7.8V and still trigger a low-battery warning because the BMS hasn't yet established where that voltage falls on its own curve. This is not a faulty cell — it's a calibration gap. One full charge cycle from within the camera body or OEM charger resets this mapping. After that cycle, the indicator tracks actual charge state correctly.

Battery percentage jumping erratically during EYE-TREK recording

Erratic percentage jumps — for example, dropping from 60% to 20% mid-session then recovering — happen when the BMS voltage thresholds don't yet match the new cell's discharge curve. New lithium-ion cells have a slightly flatter mid-range voltage profile than a worn original, so the camera misreads transitions between charge bands. This is a software-side mapping issue, not a hardware fault. Fully discharge the cell to the camera's auto-shutoff point, then charge to 100% in one uninterrupted cycle — after that reset, the percentage display stabilises.