Nexto DI ND2700 Replacement Battery 3.7V 2000mAh

Nexto DI ND2700 / DI ND2725 — 3.7V Li-Polymer Replacement Battery (NENA-21120)

This 3.7V, 2000mAh lithium-polymer battery replaces the internal cell in the Nexto DI ND2700 and DI ND2725 portable storage devices. It also fits the ND2325 and related models sharing the same battery bay and connector. When the original cell degrades, this replacement restores field operation for backing up memory cards without a computer.

• ND2700 / ND2725 / ND2325 platform: These models share the same 3.7V single-cell architecture, battery connector, and BMS handshake protocol. One cell revision covers the full range — no adapter or firmware workaround needed.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the ND2700 platform. The BMS accepted the new cell without fault flags, and the charge controller stepped through its standard constant-current to constant-voltage transition cleanly.
• First-cycle calibration on the ND2700: After fitting this battery, let the device charge to 100% via its USB port before use. The ND2700 firmware reads state-of-charge from a coulomb counter that resets during installation — skipping this step causes the capacity bar to display incorrectly from the first session.

ND2700 battery error immediately after fitting a new cell

The ND2700's battery management firmware checks cell voltage and internal resistance at startup. A new lithium-polymer cell that has been stored at partial charge can read slightly outside the expected window, triggering a transient error on first power-on. This is not a fault with the cell. Connect the device to USB power and allow the charger to begin the constant-current phase — the error clears once the firmware confirms a rising charge curve above 3.5V and accepts the new cell as valid.

Capacity gauge reads low after replacing the ND2700 battery

The ND2700 stores its capacity estimate in firmware, not in the cell itself. Installing a new 2000mAh cell does not automatically reset that estimate — the device may show 60–70% full capacity until a complete charge-discharge calibration cycle is run. Charge fully to 100%, then allow the device to run through a normal backup operation until the low-battery warning triggers. Recharge fully after that point. The firmware recalculates the 2000mAh baseline from the measured cycle and the gauge corrects to rated capacity.