BLU Charleston C4C08T Replacement Battery 3.7V 550mAh

BLU Charleston / Click Series — 3.7V Li-ion Replacement Battery (C4C08T)

This is a 3.7V Li-ion replacement battery rated at 550mAh (2.04Wh), sourced for BLU Charleston, Click, Click Lite, Deco Mini, and a further twelve compatible models. It slots directly into devices using the C4C08T, C4C50T, C4C60T, or C4C85T OEM part numbers. If your original cell has swollen, holds no charge, or the phone dies unexpectedly at partial charge, this is the replacement cell.

• Charleston and Click platform compatibility: These BLU budget-tier handsets share a common 3.7V single-cell architecture and the same connector footprint across the Charleston, Click, Click Lite, and Deco Mini lines. The BMS on each accepts the same charge termination voltage, so one cell covers the full group without modification.
• Bench tested on actual hardware: We cycled this cell on a Charleston unit and monitored BMS handshake at charge initiation, mid-cycle current draw, and termination cutoff at 4.2V. The protection circuit tripped correctly on overcurrent and recovered cleanly on reset — no anomalies across three full cycles.
• Fuel gauge recalibration after installation: On first use, disable any fast-charge adapter and run one full discharge-to-charge cycle at standard current. This lets the fuel gauge IC map the new cell's discharge curve before committing a calibration baseline — skipping this step is the primary reason percentage readings jump erratically after a cell swap.

Sudden shutdown at 20–30% on the BLU Charleston after a cell swap

This is a voltage cliff issue, not a capacity problem. At 20–30% state of charge, the modem radio and display pull simultaneous load spikes. If the new cell's internal impedance is slightly higher than the aged cell the fuel gauge was calibrated to, voltage sags below the BMS cutoff threshold — typically 3.0V — and the phone cuts out even though the gauge shows charge remaining. The fix is one full discharge-charge cycle so the coulomb counter recalibrates to the actual cell curve. After that cycle, the shutdowns stop.

Phone feels warm near the battery during the first few charges

A new Li-ion cell starts with higher internal impedance than a broken-in cell. The charge IC pushes current into that resistance, and some energy converts to heat rather than stored charge — this is normal for the first two to three cycles. You should see warmth reduce noticeably by the third full charge. If the device stays hot beyond cycle three or the back panel distorts, stop charging and inspect the cell for swelling.