About this replacement
Zebra EC30 / EC300K — 3.85V Li-Polymer Replacement Battery (BT-000386)
This 3.85V, 1100mAh Li-Polymer cell replaces the OEM pack in the Zebra EC30 and EC300K mobile computers. These are compact handheld devices used in retail, warehouse, and logistics environments for barcode scanning and real-time inventory processing. Voltage and capacity match the original specification exactly — no reconfiguration needed.
- EC30 and EC300K compatibility: Both models share the same battery bay dimensions, connector pinout, and BMS handshake protocol. The EC300K is a variant of the EC30 platform — same voltage rail, same charge termination logic, same pack.
- Bench tested on actual hardware: We cycled this pack through the EC30's charge controller and confirmed the BMS completed a full charge-terminate sequence without fault flags. Scan-trigger inrush and wireless radio draw were measured simultaneously — the cell held voltage within the acceptable window throughout.
- First-shift preparation on the EC30: After installing the new pack, seat the scanner in its cradle and run a complete charge cycle before starting pick-and-pack operations. Scan-trigger inrush current peaks when the cell is near its minimum charge level — a fully charged cell prevents a BMS protection trip on the first active shift.
Cradle showing a charging error on a new EC30 pack
The EC30 cradle reads pack state through spring-loaded dock contacts on the base of the device. Oxidation or debris on either the cradle pins or the battery contacts creates enough resistance to trigger a charge-fault signal before current even flows. This is not a defective cell — it is a contact resistance issue. Wipe the battery contacts and cradle pins with a dry cloth, reseat the device firmly, and confirm the amber charge LED activates within 10 seconds.
EC30 dropping wireless connection during rapid scan bursts
The EC30 runs its wireless radio and imager simultaneously during high-frequency scanning. The combined inrush from the scan trigger and the radio transmit pulse can cause a momentary voltage sag if the cell is below roughly 3.6V under load. The BMS interprets that sag as an undervoltage event and briefly cuts output, which drops the wireless session. Keeping the pack above 20% charge during active scanning shifts eliminates this fault pattern.