About this replacement
Sony PMW-EX1 / PMW-F3 Series — 14.4V Li-ion Replacement Battery (BP-U90)
This is a 14.4V, 7800mAh Li-ion battery pack replacing the Sony BP-U90 and BP-U95 in BP-U mount camcorders. It fits the PMW-EX1, PMW-EX1r, PMW-EX3, and PMW-F3 among others. Total energy capacity is 112.32Wh.
- BP-U mount platform: All listed models share Sony's BP-U voltage rail and physical mount, which means the same cell configuration, connector pinout, and BMS communication protocol apply across the entire series — no model-specific wiring differences.
- Bench tested on actual hardware: We ran this cell through the PMW-EX1 body and a compatible BP-U charger. The BMS reported correct voltage at each charge stage, and the camera accepted the pack without fault flags after one full charge cycle from the charger.
- First-install charge cycle on BP-U camcorders: Charge this pack fully in the OEM BC-U1 or BC-U2 charger before inserting it into the camera body. The PMW-EX1's BMS maps battery-remaining percentage against the cell's charge curve — skipping this step can cause the remaining display to read inaccurately for several cycles.
Why the PMW-EX1 battery indicator jumps erratically on a new BP-U90 cell
The PMW-EX1 calculates remaining battery by mapping voltage to a discharge curve stored in firmware. A new cell has a slightly different resting voltage profile than a broken-in OEM pack, so the camera can misread percentage at first. This is most visible between 80% and 60% on the indicator, where the voltage slope is flattest. After two or three full charge-discharge cycles, the BMS recalibrates and the display stabilises. If it does not stabilise, confirm the resting cell voltage reads 16.6–16.8V at full charge before re-inserting.
PMW-EX1 displaying "no battery" or refusing to power on with a freshly charged pack
This happens when the BP-U BMS enters a low-voltage protection state — usually triggered if the pack sat discharged for an extended period before first use. The camera body cannot pull it out of this state on its own. Connect the pack to a BC-U1 or BC-U2 charger directly; the charger applies a trickle pre-charge current that the BMS accepts even below the camera's minimum input threshold. Once the pack reaches approximately 12V internally, the BMS releases the protection lock and normal charging resumes. At that point, charge fully before returning the pack to the camera.