BLU Studio C 8.8 Compatible Battery 3.8V 2500mAh C866042300L

BLU Studio C 8.8 / S270Q — 3.8V Li-ion Replacement Battery (C866042300L)

This is a 3.8V, 2500mAh Li-ion battery for the BLU Studio C 8.8 and S270Q smartphones. It replaces OEM part C866042300L and restores power to devices where the original cell has degraded or failed to hold a charge. Dimensions are 86.10 × 60.00 × 4.30 mm — confirm these against your existing cell before installing.

• Studio C 8.8 and S270Q compatibility: Both models share the same PCB layout, connector pinout, and BMS handshake protocol — one cell fits both. The voltage rail is identical at 3.8V nominal, so no adapter or modification is needed.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the Studio C 8.8 platform. The BMS accepted the handshake without fault codes, and the fuel gauge IC registered capacity within expected tolerance on the second full cycle.
• Fuel gauge recalibration on first use: Disable fast charging for the first complete discharge-charge cycle after installation. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging pushes current into an uncalibrated register.

Sudden shutdown at 20–30% on the BLU Studio C 8.8

This happens when the cell cannot sustain voltage under combined modem and display load. Even if the coulomb counter reads 20–30%, voltage at the cell terminals drops below the BMS cutoff threshold during a high-draw spike — the phone shuts down instantly. A new cell eliminates this because the internal resistance is lower and the voltage curve holds steadier under load. After fitting the replacement, run one full discharge-charge cycle without fast charging to let the fuel gauge IC recalibrate against the new discharge curve.

Phone warm near the battery during first charge after a cell swap

A new Li-ion cell has higher internal impedance than a broken-in cell, so the charge IC pushes slightly more voltage to compensate — that converts to heat during the first few cycles. This is normal and tapers off as the cell's impedance settles. If the phone stays warm beyond the third full charge cycle, check that the back cover is seated flat with no air gap trapping heat. Warmth that continues past cycle three at the same intensity warrants a closer look at charger output — keep input voltage at 5V, 1–2A for the first cycle.