Tele2 Comviq 3.7V Replacement Battery 1300mAh Li-ion

Tele2 Comviq — 3.7V Li-ion Replacement Battery

This is a 3.7V, 1300mAh (4.81Wh) Li-ion replacement battery for the Tele2 Comviq mobile phone, sold under the Comviq brand in Nordic markets. It fits the ZTE 950 series hardware platform that underpins this handset. If the original cell has degraded or the phone no longer holds a charge, this replaces it directly.

• ZTE 950 platform fit: The Comviq handset runs on ZTE 950 series hardware. The battery connector, cell dimensions (43.50 × 47.00 × 6.10mm), and BMS voltage rails match that platform. The replacement cell seats correctly without modification.
• Bench tested on actual hardware: We ran this cell through charge and discharge on the ZTE 950 platform. The BMS accepted the cell without error flags, charge termination triggered correctly at 4.2V, and the fuel gauge IC tracked state-of-charge without stepping erratically.
• First-cycle fuel gauge reset: After fitting this cell, run one full discharge to the auto-shutoff point, then charge uninterrupted to 100% before normal use. This recalibrates the coulomb counter against the new cell's discharge curve and prevents the phone reporting inaccurate percentages from day one.

Sudden shutdown at 20–30% on the replacement cell

This is a voltage cliff issue, not a capacity issue. When the modem transmits or the screen brightness spikes, current draw pulls the cell voltage below the BMS cutoff threshold — even though the fuel gauge still shows charge remaining. It happens most often when the fuel gauge IC is still calibrated to the old cell's discharge curve. Run one full discharge-charge cycle after installation. If shutdowns continue past that point, check that the cell is seated flat and the connector is fully latched, then recheck at the 25% mark with the screen on full brightness.

Phone not powering on after the battery sat discharged in storage

Li-ion cells that drop below approximately 2.5V per cell trigger a BMS lockout to prevent damage from over-discharge. The phone will show nothing — no boot screen, no charge indicator — because the BMS is blocking current flow. Connect the phone to a low-current charger (a standard 5V USB wall adapter, not a fast charger) and leave it for 20–30 minutes without pressing the power button. Once the cell recovers past the BMS re-enable threshold, the charge indicator will appear. After that, allow a full charge to 4.2V before first use.