BL-05 LAMTAM Nokia E11 Replacement Battery 3.7V 750mAh

LAMTAM E11 / E16 Series — 3.7V Li-ion Replacement Battery (BL-05)

This is a 3.7V, 750mAh Li-ion cell that replaces the original BL-05 battery in Nokia E11, E16, LT826, and LT828 handsets. It restores basic device functions — calling, messaging, and on-device apps — when the original cell has degraded or failed. Capacity is 750mAh (2.78Wh) as rated.

• E11, E16, LT826, LT828 compatibility: These four models share the same battery bay dimensions (53.00 × 33.90 × 5.70mm), the same 3.7V single-cell voltage rail, and the same BL-05 connector pinout — which is why one cell fits all four without modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on compatible Nokia hardware. The BMS accepted the cell without fault flags, held the charge curve within expected parameters, and showed no unexpected cutoff events during load.
• Fuel gauge recalibration after install: On first use after fitting this cell, run one full discharge down to auto-shutdown, then charge uninterrupted to 100%. This gives the on-device coulomb counter a clean reference point against the new cell's actual discharge curve before the OS starts reporting percentages.

Sudden shutdown at 20–30% on the E11 after a cell swap

A fresh Li-ion cell has a steeper voltage cliff than a well-worn original. When the E11's modem fires up for a call or the screen brightness spikes, current draw pulls the cell voltage down sharply — faster than the fuel gauge IC expects. The device interprets that as a critical low and shuts off, even though the percentage shown was 25%. One full discharge-to-zero followed by a full uninterrupted charge recalibrates the fuel gauge IC and eliminates most of these mid-use shutdowns. After that cycle, target a resting voltage of around 3.85–3.90V at 50% reported charge as a sanity check.

OS percentage jumping erratically in the first two days after installation

The Nokia E11's fuel gauge IC stores a learned discharge model for the old cell. When a new cell goes in, the stored curve no longer matches actual cell behaviour, so percentage readings skip or jump as the IC tries to reconcile what it sees against what it expects. This is not a fault with the replacement cell — it is the coulomb counter recalibrating. Complete two full discharge-charge cycles without removing the battery, and the jumps will stabilise. If erratic readings persist beyond three cycles, check that the battery contacts are clean and making full contact before assuming a cell fault.