BST1089SEB Compatible Battery Samsung SPH-i330 3.7V 1600mAh

Samsung SPH-i330 — 3.7V Li-ion Replacement Battery (BST1089SEB)

This is a 3.7V, 1600mAh Li-ion cell built to fit the Samsung SPH-i330 smartphone. It replaces the original BST1089SEB when the factory cell can no longer hold adequate charge for calls, messaging, or basic app use. Voltage and connector match the SPH-i330 battery bay exactly.

• SPH-i330 fitment: The SPH-i330 draws from a single-cell 3.7V Li-ion pack with a specific contact layout tied to its charge IC. This cell matches that voltage rail and connector footprint — no adapter or modification needed.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge passes on the SPH-i330 platform. The BMS responded correctly to charge termination and low-voltage cutoff at each stage without triggering false shutdown events.
• First-cycle fuel gauge reset: After fitting this cell, run one complete discharge-to-charge cycle with fast charging disabled. This gives the SPH-i330's fuel gauge IC time to map the new cell's discharge curve before high-current charging begins on an uncalibrated cell.

Sudden shutdown at 20–30% on the SPH-i330 after cell replacement

The SPH-i330's fuel gauge IC was calibrated to the discharge curve of the original cell. A new cell has a different internal impedance profile, so the IC misreads remaining capacity under load. When the modem fires during a call or the backlight peaks, voltage sags below the BMS cutoff threshold even though the gauge still shows 20–30%. One full discharge-charge cycle without interruption lets the coulomb counter re-anchor to the new cell's actual voltage cliff, typically around 3.4–3.5V under load.

SPH-i330 not powering on after the replacement cell sat in storage

Li-ion cells self-discharge during storage. If the BST1089SEB cell dropped below approximately 2.5V before installation, the BMS enters a protective lockout state and the phone will not power on. Connect the phone to a wall charger — not a USB port — and leave it for 20–30 minutes without attempting to power it on. The charge IC needs to trickle current into the cell to bring it above the BMS re-enable threshold, typically 2.8–3.0V, before normal charging resumes.