Navon BT60 Li-ion Replacement Battery 3.7V 1200mAh

Navon BT60 — 3.7V Li-ion Replacement Battery (BT60)

This is a 3.7V, 1200mAh Li-ion replacement battery for Navon smartphones that use the BT60 cell. It measures 53.00 × 33.90 × 5.70mm and matches the original form factor. Fit it when the original battery no longer holds charge or fails to power the handset.

• BT60 platform fit: Navon handsets in this range share the same battery bay dimensions, connector orientation, and 3.7V nominal voltage rail. The BT60 designation covers both the OEM part number and the fit model, so one cell serves the full compatible lineup without modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a compatible handset, confirming the BMS accepted the cell, charge termination triggered correctly at 4.2V, and no overcurrent fault tripped on boot or during modem wake events.
• Fuel gauge recalibration on first use: After fitting, disable fast charging if available and run one complete discharge down to auto-shutoff, then charge uninterrupted to 100%. This gives the fuel gauge IC a clean reference curve for the new cell before it starts tracking coulombs under load.

Why the Navon phone reports wrong battery percentage after a cell swap

The fuel gauge IC stores a learned discharge curve from the old cell. When a new cell goes in, that stored curve no longer matches the actual voltage-versus-capacity profile of the replacement. The gauge reads voltage correctly but maps it to the wrong state-of-charge percentage. One full discharge-to-shutoff followed by a full charge resets the coulomb counter and forces the IC to re-anchor its curve to the new cell's actual endpoints.

Sudden shutdown at 20–30% remaining on the replacement cell

This happens when the cell hits a voltage cliff under modem or display load before the fuel gauge predicts empty. At high current draw, internal resistance causes a rapid voltage drop that trips the BMS undervoltage cutoff — even while the reported percentage still looks safe. The fuel gauge IC hasn't yet mapped where that cliff sits on the new cell. Running two full discharge-charge cycles after fitting closes the gap; after recalibration, shutoffs should move down to below 5% reported charge.