Archos 45 Titanium AC45TI Replacement Battery 3.8V 1900mAh

Archos 45 Titanium — 3.8V Li-ion Replacement Battery (AC45TI)

This 3.8V, 1900mAh Li-ion cell replaces the original battery in the Archos 45 Titanium smartphone. It matches OEM part number AC45TI and fits both the standard 45 Titanium and Ohne Simlock variants. Capacity figures are taken directly from the product specification — 7.22Wh at 3.8V nominal.

• 45 Titanium and Ohne Simlock compatibility: Both variants share the same battery bay dimensions, voltage rail, and connector pinout. No hardware modification is needed — the cell seats directly and the charging IC recognises the same charge profile.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge on the 45 Titanium platform. The BMS accepted the charge curve without interruption, and the protection circuit tripped correctly at the low-voltage threshold — no runaway, no false cutoff mid-cycle.
• Fuel gauge recalibration on first use: After installation, disable fast charging for one complete discharge-charge cycle. The fuel gauge IC on the 45 Titanium is calibrated to the old cell's discharge curve. Running one slow cycle at standard current lets it rebuild an accurate state-of-charge map before any high-current charging session.

Sudden shutdown at 20–30% on the Archos 45 Titanium after a cell swap

The 45 Titanium's fuel gauge IC stores a learned discharge curve from the original cell. A new cell has a different internal resistance profile, so the IC misjudges remaining capacity and triggers a low-voltage shutdown earlier than the display percentage suggests. Under modem or screen load, the new cell's voltage can sag briefly below the shutdown threshold even while the gauge still reads 25%. One full slow discharge-charge cycle resets the coulomb counter and aligns the IC to the new cell's actual curve. After that cycle, the percentage readings stabilise and premature shutdowns stop.

OS reporting wrong battery percentage after replacement

Android's battery percentage on the 45 Titanium is driven by the fuel gauge IC, not a direct voltage measurement. When the old degraded cell is replaced, the IC's stored charge table no longer matches the new cell's capacity curve, so the percentage can jump, stall, or read 100% almost immediately after charging starts. The fix is straightforward: run the phone down to automatic shutdown, then charge uninterrupted to 100% without removing the cable early. After one complete cycle, the IC recalibrates its coulomb counter against the new cell. Verify recalibration is working by checking that voltage reads approximately 3.6V when the gauge shows 20%.