Alcatel OT-906 Compatible Battery 3.7V 1000mAh

Alcatel OT-906 / One Touch 906 — 3.7V Li-ion Replacement Battery (CAB31K0000C1)

This is a 3.7V, 1000mAh Li-ion cell for the Alcatel OT-906 and One Touch 906 smartphones. It replaces OEM part numbers CAB31K0000C1, TB-5J, and BY74. The cell measures 49.54 × 39.95 × 5.84mm and fits the original battery bay without modification.

• OT-906 and One Touch 906 compatibility: Both model names refer to the same hardware platform. They share the same voltage rail, connector pinout, and BMS handshake protocol, so one cell covers both variants.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the OT-906 platform. The BMS accepted the cell without error flags, and the charge IC communicated normally throughout each cycle.
• Fuel gauge recalibration after swap: On first use after installation, complete one full discharge down to automatic shutdown, then charge uninterrupted to 100% before resuming normal use. This gives the fuel gauge IC one complete reference cycle against the new cell's discharge curve before it begins tracking state-of-charge accurately.

Sudden shutdown at 20–30% on the OT-906 after a cell swap

The OT-906's fuel gauge IC stores a charge map built on the old cell's discharge curve. When a new cell goes in, the stored map no longer matches actual cell voltage under load. The modem radio and display pull brief high-current spikes that drag cell voltage below the BMS cutoff threshold — even when the reported percentage looks safe. One full discharge-to-shutdown followed by an uninterrupted full charge forces the fuel gauge IC to rebuild its reference map against the new cell. After that cycle, the percentage readout tracks actual capacity accurately.

Phone warm near the battery compartment on the first charge cycle

A fresh cell typically has higher internal impedance than a broken-in one. The charge IC on the OT-906 pushes current at its programmed rate regardless, so more energy converts to heat in the first few cycles as impedance drops. This is normal and tapers off after two or three full charge cycles. If the phone stays warm beyond the third full charge, check that the back cover is fully seated — poor contact between the cover and battery can trap heat against the cell.