Samsung Select 3.7V Replacement Battery 1000mAh Li-ion

Saiet Select — 3.7V Li-ion 1000mAh Replacement Battery

This is a 3.7V lithium-ion cell rated at 1000mAh (3.7Wh), sized at 62.02 × 37.89 × 4.37mm. It fits the Saiet Select smartphone. Use it to replace a cell that no longer holds charge or fails to power the device through a normal day.

• Saiet Select fit: The Select uses a single-cell 3.7V Li-ion pack with a fixed connector footprint. This cell matches that voltage rail and physical envelope — the connector seats flush and the BMS communicates over the same two data lines the original cell used.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the bench, confirmed the BMS reported state-of-charge correctly to the host device, and verified charge termination triggered at 4.2V without thermal event.
• Fuel gauge recalibration after install: On first use after fitting this cell, disable fast charging and run one full discharge down to automatic shutdown, then charge to 100% uninterrupted. This lets the fuel gauge IC map its coulomb counter against the new cell's actual discharge curve before fast charge current is applied.

Sudden shutdown at 20–30% on the replacement cell

This happens because the fuel gauge IC is still running the discharge curve it learned from the old, degraded cell. The new cell has a steeper voltage cliff under screen or modem load than the IC expects, so the device sees the rail drop below the shutdown threshold before the displayed percentage reaches zero. It is not a faulty cell. One full uninterrupted discharge-charge cycle forces the coulomb counter to relearn the actual curve. After that cycle, the shutdowns stop.

Device will not power on after the replacement cell sat in storage

Li-ion cells self-discharge in storage. If the cell voltage dropped below roughly 2.5V, the BMS enters lockout to prevent damage and the device will not respond to the power button or show a charge indicator. Connect the phone to a wall charger — not a PC USB port — and leave it for 15–20 minutes without pressing anything. The charge IC will trickle current into the cell until voltage rises above the BMS re-enable threshold, typically around 2.9–3.0V, at which point normal charging resumes.