B5765620003 Lenovo LePhone 3G W100 Compatible Battery 3.7V 1500mAh

Lenovo LePhone W100 — 3.7V Li-ion Replacement Battery (B5765620003)

This 3.7V, 1500mAh Li-ion cell replaces the original battery in the Lenovo LePhone 3G W100 and LePhone W100. It also fits the Lphone 3GW100 and 3GW101 variants that share the same battery bay and connector. OEM part numbers B5765620003 and BL161 both cross-reference to this cell.

• W100 and W101 platform fit: The W100 and W101 share the same 3.7V single-cell architecture, battery footprint, and connector pinout. One cell covers both variants without modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a W100 unit. The BMS accepted the charge handshake on the first cycle and held voltage through a full screen-on discharge without tripping the protection circuit.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging if available and run one complete discharge-charge cycle. This gives the fuel gauge IC a clean reference curve for the new cell before high-current charging begins — skipping this step causes the percentage display to drift or jump for the first few days.

Sudden shutdown at 20–30% on the W100 after a cell swap

A fresh cell has a different discharge curve than the degraded cell the fuel gauge IC was trained on. When the reported percentage says 25%, the actual cell voltage may have already dropped below the modem and display load threshold. The BMS then cuts power to protect the cell even though the OS still showed charge remaining. One full discharge to automatic shutdown, followed by a full charge without interruption, resets the coulomb counter and aligns the percentage reading to the new cell's curve.

Phone feels warm near the battery during the first few charges

A new cell starts with slightly higher internal impedance than a broken-in one. The charge IC pushes current against that resistance, which generates heat at the battery contact area during the first two or three charge cycles. This is normal and diminishes as the cell completes its initial cycles. If warmth persists beyond the third full charge, check that the battery connector is seated flat — a partially engaged connector increases contact resistance and adds heat.