Neffos C7 Lite Replacement Battery NBL-38A2150 3.7V 2100mAh

Neffos C7 Lite / TP7041A — 3.7V Li-ion Replacement Battery (NBL-38A2150)

This is a 3.7V, 2100mAh (7.77Wh) Li-ion cell built to replace the original NBL-38A2150 battery in the Neffos C7 Lite and TP7041A smartphones. It fits the same footprint at 80.05 × 57.80 × 4.10mm and connects to the same charge IC without modification. If your phone shuts down unexpectedly, drains fast, or won't hold a charge, this is the direct cell swap.

• C7 Lite and TP7041A compatibility: Both the C7 Lite and TP7041A run the same motherboard revision with identical connector pinout, charge IC, and BMS handshake protocol — one cell fits both without adapter or firmware difference.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the C7 Lite board. The BMS accepted the cell on first connection, charge termination triggered correctly at 4.2V, and the protection circuit tripped cleanly at the low-voltage cutoff threshold.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging and run one full discharge-charge cycle at standard rate. The C7 Lite's fuel gauge IC is calibrated to the old cell's discharge curve — one full cycle at normal current lets it map the new cell before high-current charging resumes.

Why the C7 Lite shuts down suddenly at 20–30% after a cell swap

The C7 Lite uses a coulomb-counter fuel gauge IC that retains the discharge curve of the old cell in memory. When a new cell is installed, the gauge reads remaining charge against the wrong curve. Under modem load or screen-on bursts, voltage sags faster than the gauge expects, and the phone hits the hardware undervoltage cutoff before the display reaches 0%. One full discharge-charge cycle at standard rate resets the coulomb counter and re-anchors the gauge to the new cell's actual curve. After that cycle, percentage readings stabilise and early shutdowns stop.

Phone won't power on after the replacement cell sat in storage

Li-ion cells self-discharge in storage, and if this battery dropped below approximately 2.5V per cell before installation, the BMS enters lockout mode and blocks all charge current to prevent damage. The phone will show no response — no charging indicator, no boot. Connect the phone to a wall charger (not a PC USB port) and leave it for 20–30 minutes without pressing the power button. The charge IC trickle-charges the cell at low current until voltage recovers above the BMS re-enable threshold, typically around 2.9V, at which point normal charging resumes.