CPLD-339 Coolpad V1 Replacement Battery 3.8V 2900mAh

Coolpad V1 Series — 3.8V Li-ion Replacement Battery (CPLD-339)

This is a 3.8V, 2900mAh Li-ion replacement battery for the Coolpad V1 smartphone series. It fits the V1, V1-C, V1-C Bodun TD-LTE, and 大观 5. The OEM part number is CPLD-339 — match that before ordering.

• V1 and V1-C platform compatibility: These models share the same battery bay geometry, connector pinout, and BMS handshake protocol. The CPLD-339 part number covers all four variants — voltage rail and cell dimensions are identical across the lineup.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge on V1 hardware. The BMS communicated correctly with the fuel gauge IC, accepted charge current without tripping protection, and reported state-of-charge without erratic jumps after one full calibration cycle.
• Fuel gauge recalibration on first use: After installation, disable fast charging and run one complete discharge-to-charge cycle before resuming normal use. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging pushes current into an uncalibrated cell, preventing inaccurate percentage readings from the start.

Sudden shutdown at 20–30% on the Coolpad V1 after a cell swap

This happens because the fuel gauge IC is still calibrated to the old cell's discharge curve. The new cell hits its voltage cliff — where voltage drops sharply under modem or screen load — at a different state-of-charge than the old one. The OS reads 25% but the cell voltage has already collapsed below the cutoff threshold. One full discharge-charge cycle without fast charging resets the coulomb counter and resolves this.

USB fast charge not activating on the first cycle after replacement

On first connection after a cell swap, the charge IC may default to slow charge mode because the BMS on the new cell has not yet completed its handshake with the phone's charge controller. This is a one-cycle behaviour, not a fault. Disconnect the cable, power the phone fully on, then reconnect. If fast charge still does not activate after the first full cycle, verify the cable supports the required charging protocol for the V1.