SeaLife DC2000 Pro SL747 Replacement Battery 3.7V 1050mAh

SeaLife DC2000 Pro / DC2000 — 3.7V Li-ion Replacement Battery (SL747 / SL7404)

This is a 3.7V 1050mAh Li-ion cell built to replace the original SL747 / SL7404 battery in the SeaLife DC2000 Pro and DC2000 underwater cameras. It powers the imaging sensor, processor, and internal systems during dive photography and video recording. If your current cell drains faster than it used to, or you need a spare for back-to-back dives, this is the direct replacement.

• DC2000 Pro and DC2000 compatibility: Both models share the same battery bay geometry, connector pinout, and 3.7V supply rail. The SL747 and SL7404 are interchangeable OEM part numbers for the same physical cell — either reference confirms fit on both cameras.
• Bench tested on actual hardware: We cycled this cell through the DC2000 Pro under continuous video load and stills bursts. The BMS accepted the cell without error flags, held voltage above the low-battery threshold through the full discharge run, and recharged cleanly via the OEM charger.
• First-use charge cycle for the DC2000: Run one full charge cycle inside the camera body or OEM charger before your first dive. The DC2000's battery-remaining indicator maps to a learned discharge curve — skipping this step can cause the percentage readout to jump erratically during the first session.

Why the DC2000 Pro shows a dead battery indicator on a new, charged cell

The DC2000 Pro uses a voltage-threshold system to estimate remaining charge. A new cell that has never been through a charge cycle inside the camera body starts with an uncharacterised discharge curve, so the firmware reads the open-circuit voltage incorrectly and flags it as empty. This is not a fault with the cell — it's a calibration gap between the fresh cell and the camera's internal gauge. One complete charge-to-full cycle through the OEM charger or the camera's USB port resolves it. After that cycle, the indicator tracks accurately through normal use.

Battery percentage jumping around mid-dive on the DC2000

Erratic percentage readings mid-dive usually mean the camera's gauge hasn't yet mapped the replacement cell's discharge curve. Li-ion cells from different production batches can have slightly different voltage-versus-capacity slopes, and the DC2000's indicator system takes one or two full cycles to track a new cell correctly. The cell itself is not failing — the readout catches up after a couple of full charge-and-discharge cycles. If the jumping persists past the third cycle, check that the cell is sitting fully seated in the bay and that the contacts are clean and dry before ruling out a connector issue.