BLU BOLD N1 Replacement Battery 3.8V 3300mAh C736048350L

BLU BOLD N1 — 3.8V Li-Polymer Replacement Battery (C736048350L)

This 3.8V, 3300mAh lithium-polymer battery replaces the OEM cell in the BLU BOLD N1 smartphone. It fits the BOLD N1 directly, matching the original connector, cell dimensions (75.04 × 59.20 × 4.50mm), and BMS communication protocol. Capacity is 3300mAh — identical to the factory specification.

• BOLD N1 platform fit: The BOLD N1 uses a single-cell Li-Polymer pack at 3.8V nominal. The OEM BMS on this platform handshakes with the charge IC over a single-wire thermistor line. This cell carries the matching NTC thermistor, so the charge IC accepts it without throwing a fault.
• Bench tested on actual hardware: We cycled this cell through charge, idle, and load draws that mirror screen-on and modem activity. The BMS held the 4.35V charge ceiling correctly and cut off at 3.0V on discharge without dropping to a lockout state.
• Fuel gauge recalibration on first cycle: On first use after installation, disable fast charging and run one complete discharge-to-charge cycle at standard current. This lets the fuel gauge IC map its coulomb counter against the new cell's actual discharge curve before fast charging pushes high current into an uncalibrated cell.

Sudden shutdown at 20–30% on the BOLD N1 after a cell swap

The BOLD N1's fuel gauge IC holds a learned discharge curve from the old, degraded cell. When a fresh cell with a steeper, healthier voltage curve goes in, the IC misreads the state of charge. Under modem or display load, the cell voltage dips briefly below the shutdown threshold even though the reported percentage still reads high. One full discharge-to-charge cycle lets the coulomb counter reset against the new curve. After that cycle, shutdowns at 20–30% stop.

USB fast charge not activating on the first cycle after replacement

On the first charge after installation, the charge IC may default to a slow trickle rate rather than engaging fast charge. This happens because the IC treats any new, uncalibrated cell as a potential recovery charge — it holds back current until it confirms the cell voltage is stable above 3.5V. Plug in, leave it alone, and let the first charge complete at whatever rate the IC sets. Fast charge re-engages normally on the second cycle once the IC has confirmed cell health.