Motorola Nextel i1000 Compatible Battery 3.7V 1150mAh

Motorola Nextel i1000 / i2000 — 3.7V Li-ion Replacement Battery

This is a 3.7V, 1150mAh Li-ion cell built to fit the Motorola Nextel i1000 and i2000 push-to-talk mobile phones. Both devices share the same battery bay geometry and voltage rail, so one cell covers the pair. Capacity figure is 1150mAh (4.26Wh) — use that number, not anything printed on an aging original pack.

• i1000 and i2000 shared battery platform: Both Nextel handsets run off the same 3.7V single-cell architecture with an identical connector pinout and BMS handshake. Swapping between models requires no adapter or modification.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge on the i1000 platform. The BMS accepted charge current cleanly, reported cell state correctly to the host, and held voltage under PTT transmission load without tripping protection.
• Fuel gauge recalibration on first use: After installation, run one complete discharge to auto-off followed by a full uninterrupted charge before enabling any fast-charge mode. This lets the fuel gauge IC map the new cell's discharge curve and prevents erratic percentage readings during normal use.

Why the i1000 reports wrong battery percentage after a cell swap

The i1000 uses a coulomb-counter-based fuel gauge IC that stores a discharge curve calibrated to the original cell's impedance profile. A new cell has a different internal resistance, so the stored curve no longer matches actual cell behaviour. The gauge reads state-of-charge against the old map and reports numbers that drift from reality — often showing full charge then dropping suddenly. One complete discharge-to-cutoff followed by a full charge resets the reference and restores accurate percentage display.

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

This is a voltage cliff failure, not a capacity problem. Under peak load — PTT transmission or screen backlight — the cell voltage sags faster than the fuel gauge predicts, crossing the BMS undervoltage cutoff threshold while the display still shows charge remaining. It happens most on an uncalibrated gauge reading from a stale curve. Run the phone down to auto-off once, charge fully to 4.2V, and the gauge recalibrates its cutoff prediction against the actual cell curve.