Emporia Elson EL350 Replacement Battery 3.7V 1050mAh

Emporia Elson EL350 Series — 3.7V Li-ion Replacement Battery (BTY26169)

This 3.7V, 1050mAh Li-ion cell replaces the original BTY26169 battery in the Emporia Elson EL350 and EL350 Dual, including Mobistel-branded variants of both models. It measures 54.60 × 34.00 × 5.50mm and slots directly into the same battery bay. Capacity matches the factory spec at 3.89Wh — no modifications needed.

• EL350 and EL350 Dual compatibility: Both the single-SIM and Dual-SIM versions of this phone use the same battery bay dimensions, voltage rail, and connector pinout. One cell fits all four variants — Elson and Mobistel badging share the same hardware platform.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the EL350 platform. The BMS accepted the charge current without tripping, voltage held steady across the discharge curve, and the protection circuit cut off cleanly at the low-voltage threshold.
• Fuel gauge recalibration on first use: After fitting this cell, run one full discharge down to automatic shutdown, then charge uninterrupted to 100% before use. The EL350's fuel gauge IC was calibrated to the worn-out original cell — skipping this cycle causes the percentage display to read inaccurately from the first charge.

Sudden shutdown at 20–30% on the Elson EL350

This is the most common complaint on EL350 units with a degraded original cell. As the cell ages, its internal resistance rises. When the modem transmits or the screen brightens, current draw spikes and the cell voltage drops sharply — past the BMS cutoff threshold — even though the fuel gauge still shows charge remaining. A fresh cell with lower internal resistance holds voltage under that same load spike. If the shutdown persists after fitting a new cell, run one full calibration cycle to let the fuel gauge IC re-anchor its voltage-to-percentage mapping to the new cell's discharge curve.

Phone won't power on after the battery sat in storage

Li-ion cells left unused for several months can self-discharge below 2.5V per cell. At that level, the BMS enters lockout mode to prevent damage — the phone shows nothing when you press the power button. Connect the EL350 to a charger and leave it for 15–20 minutes without pressing any buttons; the charge IC applies a low-current trickle to bring the cell back above the BMS recovery threshold. Once the screen shows a charging indicator, the BMS has re-initialised and normal charging resumes. If no indicator appears after 30 minutes, the cell has discharged too deeply to recover and needs replacement.