About this replacement
BLU Dash 5.0 / D410 Series — 3.7V Li-ion Replacement Battery (C726004200T)
This is a 3.7V, 2000mAh Li-ion battery for the BLU Dash 5.0, D410, D410a, and D410i smartphones. It replaces OEM part number C726004200T. Swap it in when the original cell no longer holds charge or causes unexpected shutdowns.
- D410 series compatibility: The D410, D410a, and D410i all share the same battery bay geometry, connector pinout, and BMS handshake logic — one cell fits the full variant range without modification.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on a D410 unit. The BMS accepted the charge current without tripping, and the protection circuit cut off cleanly at the low-voltage threshold.
- Fuel gauge recalibration on first install: On first use, disable fast charging if available and run one complete discharge-to-charge cycle. The fuel gauge IC calibrates its coulomb counter against the new cell's discharge curve — skipping this step causes the percentage readout to drift for the first several cycles.
Why the Dash 5.0 reports wrong battery percentage after a cell swap
The Dash 5.0 uses a fuel gauge IC that builds its capacity model from the previous cell's charge and discharge history. When you install a new cell, that learned model no longer matches the actual discharge curve of the fresh battery. The IC will show inflated or deflated percentages until it collects enough cycle data to recalibrate. One full discharge down to automatic cutoff, followed by an uninterrupted charge to 100%, resets the coulomb counter and brings the readout back into line.
Sudden shutdown at 20–30% remaining on the replacement cell
This happens when the fuel gauge IC is still mapped to the old cell's voltage-to-capacity curve. Under a high-draw load — mobile data, screen-on, or audio playback — the new cell's terminal voltage drops faster than the IC expects, and the phone hits the hardware cutoff before the display reads zero. The fix is not a settings change. Fully discharge the phone until it shuts itself off, charge to 100% without interruption, and repeat once more. After two full cycles the IC's curve realigns with the new cell and the early cutoffs stop. Target at least 3.7V resting voltage before assuming the cell is at fault.