NEC DB2000 Replacement Battery 3.7V 1150mAh MRD-BAT-0017-01

NEC DB2000 Series — 3.7V Li-ion Replacement Battery (MRD-BAT-0017-01)

This is a 3.7V 1150mAh Li-ion replacement battery for the NEC DB2000 mobile phone. It also fits the DB2100, DB1100, and DB1000 — all share the same voltage rail and OEM part number MRD-BAT-0017-01. Capacity is rated at 1150mAh (4.26Wh), matching the original specification.

• DB2000 / DB2100 / DB1100 / DB1000 compatibility: These four models share the same battery footprint, connector pinout, and BMS handshake requirements, which is why a single cell covers all four. Swapping between models does not change the chemistry or voltage demand.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the bench and confirmed the BMS communicates correctly with the charge IC — no false-full cutoffs and no refused charge events on the first cycle.
• Fuel gauge recalibration after installation: After fitting this cell, run one complete discharge down to auto-shutdown, then charge to 100% without interruption. This gives the fuel gauge IC a full reference curve against the new cell before the OS starts reporting percentages you can trust.

Sudden shutdown at 20–30% on the DB2000 replacement cell

The DB2000's fuel gauge IC stores a discharge curve calibrated to the original cell. When a new cell is installed, the stored curve no longer matches the actual voltage-versus-capacity relationship of the replacement. The phone reads 25% remaining but the cell voltage has already dropped below the modem's minimum operating threshold — so the processor cuts power to protect the hardware. This is not a defective cell; it is a calibration mismatch. One full discharge-to-shutdown followed by a full uninterrupted charge resolves it. After that cycle the fuel gauge IC rewrites its reference and shutdowns stop occurring above 10%.

Phone warm near the battery during the first charge cycle

A fresh Li-ion cell from storage has higher internal impedance than a cell that has been cycled. The DB2000's charge IC pushes current into this higher-impedance cell and the energy not stored as charge dissipates as heat — concentrated around the battery bay. This is normal on cycle one and reduces significantly by cycle two or three as impedance drops. If the device still runs noticeably warm after three full cycles, check that the battery contacts are clean and making full contact, since a partial connection forces the charge IC to work harder against added resistance.