About this replacement
Coolpad E600 / D280 / D520 / E200 — 3.7V Li-ion Replacement Battery (CPLD-35)
This is a 3.7V, 1150mAh Li-ion cell built to the CPLD-35 specification. It fits the Coolpad E600, D280, D520, and E200 smartphones. Voltage and connector pinout match the original factory spec.
- E600 / D280 / D520 / E200 platform fit: These four models share the same battery bay dimensions, 3.7V rail, and connector layout. One cell covers all four because the BMS handshake and contact positions are identical across the platform.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the bench. The BMS accepted charge without tripping the overcurrent cutoff, and the protection circuit responded correctly to simulated low-voltage conditions at the 2.5V threshold.
- Fuel gauge recalibration on first use: On first installation, run one full discharge to near-empty before charging to 100%. The phone's fuel gauge IC is still calibrated to the old cell's discharge curve — skipping this step causes erratic percentage readings and early low-battery warnings.
Sudden shutdown at 20–30% on the Coolpad E600
This happens when the cell voltage drops below the modem's minimum rail requirement under load, even though the fuel gauge still reads 20–30%. A fresh replacement cell has a steeper discharge curve than the aged original — the phone's coulomb counter has not yet mapped it. The BMS cuts power before the displayed percentage reaches zero. One full discharge-charge cycle forces the fuel gauge IC to remap the curve against the new cell, and the shutdowns stop.
Phone warm near the battery during first few charges after replacement
A new cell has higher internal impedance than a broken-in one. During the first charge cycles, the charge IC pushes current into a cell that is not yet at minimum impedance, and that resistance converts some energy to heat. This is normal and tapers off after three to five full cycles as impedance drops. If the device stays warm past five cycles, check that no third-party charging adapter is pushing voltage above 5V into this 3.7V nominal cell.