Vodafone Mini D100 Replacement Battery 3.7V 900mAh

Vodafone Mini D100 / Mini D101 — 3.7V Li-ion Replacement Battery

This 3.7V 900mAh Li-ion battery replaces the original cell in the Vodafone Mini D100 and Mini D101 smartphones. It restores power where the original has degraded or failed to hold charge. Capacity figure is 900mAh (3.33Wh) as specified in the product data.

• Mini D100 and D101 compatibility: Both models share the same battery bay dimensions, voltage rail, and connector pinout — 46.20 x 34.14 x 5.68mm physical footprint. The cell slots directly into either handset without modification.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the Mini D100. The BMS accepted charge from the onboard charge IC without tripping, and voltage held stable across screen-on and standby draw states.
• Fuel gauge recalibration on first use: After installation, disable fast charging if available and run one full discharge-to-charge cycle before normal use. This gives the fuel gauge IC time to map the new cell's discharge curve — skipping this step is the main reason percentage readings jump erratically in the first day.

Why the Mini D100 reports wrong battery percentage after a cell swap

The fuel gauge IC stores a learned discharge curve from the original cell. When a new cell goes in, that stored curve no longer matches the actual voltage-to-capacity relationship of the replacement. The IC reads voltage but maps it against old data, so it reports percentages that are off — sometimes by 15–20%. One complete discharge down to automatic shutdown followed by a full charge to 100% forces the IC to rewrite its reference curve against the new cell.

Sudden shutdown at 20–30% on the replacement cell

This is a voltage cliff issue, not a capacity fault. Under load from the modem radio or display, the cell voltage drops sharply at a certain state of charge — faster than the fuel gauge IC predicted. The phone's protection circuit triggers a cutoff before the percentage reaches zero. If this happens after the first cycle, run a second full discharge-charge cycle; the IC recalibrates its cutoff threshold against the new cell's actual voltage curve. After two full cycles the shutdown point should stabilise above 5%.