About this replacement
Zebra EC50 / EC55 Series — 3.85V Li-Polymer Replacement Battery (BT-000424)
This 3.85V, 4100mAh lithium-polymer pack replaces the OEM battery in the Zebra EC50 and EC55 handheld mobile computers. It covers part numbers BT-000424, BT-000424-08, BT-0000424A, BTRY-EC5X-ST1-01, and BTRY-EC5X-EX1-01. The EC50 and EC55 share the same battery bay, connector pinout, and BMS handshake protocol, so one pack covers both platforms.
- EC50 and EC55 platform fit: Both devices run the same 3.85V power rail with identical dock connector geometry and BMS authentication. A single replacement pack works across the full EC5X series without modification or adapter.
- Bench tested on actual hardware: We cycled this pack through repeated scan-burst sequences on the EC55 and monitored the BMS response to combined imager and wireless radio draw. Voltage held stable under simultaneous Wi-Fi polling and trigger actuation — no unexpected cutoffs during the test.
- First-shift preparation for EC5X docks: After installing, seat the scanner in its charging cradle and run a full charge cycle before the first pick-and-pack shift. The scan trigger inrush current peaks when the cell is near minimum — starting the shift from a full charge prevents false BMS protection trips on the first trigger pull of the day.
Cradle showing a charging error on a new EC5X pack
The EC50 and EC55 docks authenticate the battery through the connector contacts before allowing charge current to flow. If the dock reports a charging error on a brand-new pack, the most common cause is contact resistance — debris or oxidation on either the dock pins or the battery contact strip breaks the communication handshake. Wipe the battery contacts and dock pins with a dry lint-free cloth and reseat the device firmly. The dock should clear the error within 10–15 seconds of a clean connection.
Scanner losing wireless connection during rapid scan bursts
During fast barcode scanning the EC55 draws simultaneously from the imager, the processor, and the Wi-Fi radio — all at the same moment the trigger is pulled. If the cell voltage sags below approximately 3.4V under that combined inrush load, the radio subsystem drops its connection before the imager even reports a read. This happens most often when the battery is already partially depleted heading into a high-volume scan session. Start intensive scan bursts with the pack above 50% state of charge to keep instantaneous voltage above the radio's minimum threshold.