About this replacement
Sharp TM100 — 3.7V Li-ion Replacement Battery (CE-BL100)
This is a 3.7V 650mAh Li-ion replacement cell for the Sharp TM100 smartphone. It replaces OEM part CE-BL100 when the original cell degrades or fails to hold charge. Capacity and connector match the original specification exactly.
- TM100 cell format: The TM100 uses a compact 650mAh cell with a low-current BMS tuned to the phone's modest power draw. The connector pinout and protection circuit board dimensions match the original, so the cell seats correctly without modification.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on TM100-class hardware. The BMS engaged cutoff cleanly at both the low-voltage floor and the 4.2V charge ceiling, with no thermal events during the charge phase.
- Fuel gauge recalibration on first install: On first use after installation, disable any fast-charge mode and run one complete discharge-charge cycle at standard rate. This lets the phone's fuel gauge IC map the new cell's discharge curve before making percentage calculations — skipping this step causes erratic percentage readings in early use.
Sudden shutdown at 20–30% on the TM100 after a cell swap
This happens because the fuel gauge IC is still referencing the old cell's voltage curve. A new cell at 3.65V may look like 20% to the old calibration data, but its actual usable capacity runs out faster under screen and modem load. The phone's BMS then hits the low-voltage cutoff before the percentage counter reaches zero. Run one full discharge to shutdown, then a full charge without interruption — after that cycle the gauge recalibrates and shutdowns stop.
TM100 not powering on after the replacement cell sat in storage
Li-ion cells self-discharge in storage, and if voltage drops below roughly 2.5V the BMS enters lockout to prevent damage. A locked-out BMS blocks all current flow, so the phone appears completely dead. Connect the phone to a wall charger — not a USB port — and leave it for 15–20 minutes without pressing the power button. The charger trickle-feeds the cell back above the BMS recovery threshold, typically around 2.9V, after which normal charging resumes.