About this replacement
Sprint Diamond Pro / VX6950 / PPC6850 — 3.7V Li-ion Replacement Battery (BTR6850)
This 3.7V, 2400mAh Li-ion battery replaces part numbers BTR6850, BTR6850B, and 35H00111-12M. It fits the Sprint Diamond Pro, VX6950, PPC6850, and MP6590 Windows Mobile PDAs. If your original cell no longer holds adequate charge during business use, this is the direct replacement.
- Diamond Pro / VX6950 platform compatibility: These four models share the same battery bay dimensions, 3.7V power rail, and connector pinout. The BMS on each handshakes with the same cell spec, so all four accept this replacement without modification.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on a PPC6850 unit. The BMS accepted the cell on first insertion, voltage stabilised at 3.7V nominal, and the protection circuit tripped correctly at the low-voltage cutoff threshold without hanging the device.
- Sync before you swap: Perform a full data sync to the host computer before removing the battery. The Diamond Pro stores open files and application state in RAM powered directly by the main cell. Removing the battery without syncing first will erase any unsaved data in active memory.
Why the Diamond Pro won't boot after a new battery is fitted
The Diamond Pro boot sequence requires a minimum voltage before the device will power on. Replacement cells ship at a partial state of charge — often below that threshold — so the device appears dead even though the battery is functional. This is not a fault with the handset or the cell. Connect the device to a charger for at least 30 minutes before attempting the first boot, then press the power button.
Battery life noticeably shorter during active wireless sync or scanning sessions
The wireless radio and any active data transmission draw significantly more current than standby or basic PIM use. Under sustained sync loads, the cell voltage can sag enough to trigger the BMS low-voltage cutoff early, making the battery appear weaker than its rated 2400mAh. This is a draw characteristic, not a defective cell. To extend active session length, lower the display backlight to its minimum setting and close background applications before initiating a wireless sync.