F-S1 BlackBerry Torch Replacement Battery 3.7V 1200mAh

BlackBerry Torch 9800 / Torch 2 9810 — 3.7V Li-ion Replacement Battery (F-S1 / BAT-26483-003)

This is a 3.7V, 1200mAh Li-ion replacement cell for the BlackBerry Torch 9800 and Torch 2 9810 smartphones. It uses OEM part numbers F-S1 and BAT-26483-003. The cell fits the slide-form Torch body and restores full board power to the touchscreen, keyboard, and radio stack.

• Torch 9800 and 9810 fitment: Both Torch models share the same battery bay dimensions and connector pinout. The F-S1 cell services both variants — the voltage rail and BMS handshake are identical across the 9800 and 9810 board revisions.
• Bench tested on actual hardware: We cycled this cell on a Torch 9810 under mixed screen-on and radio-active load. The BMS held a stable voltage floor and cut off cleanly at the low-voltage threshold without triggering a hard lockout.
• Fuel gauge recalibration on first use: After fitting this cell, run one complete discharge down to auto-shutdown, then charge uninterrupted to 100% before resuming normal use. The Torch fuel gauge IC is calibrated against the old cell's discharge curve — one full cycle resets the coulomb counter against the new cell's actual capacity.

Why the Torch 9810 reports wrong battery percentage after a cell swap

The Torch uses a fuel gauge IC that tracks charge by counting coulombs against a stored discharge curve from the original cell. A new cell has a different internal resistance and a slightly different voltage-to-capacity profile. Until the IC runs a full discharge-charge cycle with the new cell, it interpolates percentage from stale data. The result is percentage jumps, early low-battery warnings, or a reading that freezes near 50%. One uninterrupted full cycle corrects the stored curve.

Sudden shutdown at 20–30% on the replacement cell

This is a voltage cliff problem, not a capacity problem. When the Torch screen and radio stack draw peak current simultaneously, a cell with any elevated internal resistance drops voltage sharply under load. If the instantaneous voltage dips below the BMS cutoff — typically around 3.0V — the board shuts down even though the resting charge reads 20–30%. Let the phone sit for two minutes after shutdown; if it reboots and shows charge remaining, the cell is dropping under load rather than being genuinely empty. A fresh cell with low internal resistance eliminates the sag.