About this replacement
Zebra MC33 / MC330 Series — 3.7V Li-ion Replacement Battery (BT-000337)
This 3.7V, 2700mAh Li-ion battery replaces the OEM pack in the Zebra MC33, MC330, MC330K, and MC330M mobile computers. These are rugged handheld barcode scanners used in retail and warehouse environments. It matches the original voltage rail and connector, and drops straight into the existing battery bay.
- MC33 and MC330 family fit: The MC33, MC330, MC330K, and MC330M all share the same 3.7V battery bay, connector pinout, and BMS communication protocol. One pack covers the full range without modification.
- Bench tested on actual hardware: We ran this pack in an MC330K under combined scan-trigger and Wi-Fi polling load. The BMS held the 3.7V rail steady through sustained burst scanning and did not trip on inrush from the imager module.
- First-shift preparation: After installing, place the scanner in its cradle for a full charge cycle before using in pick-and-pack. Scan-trigger inrush current is highest when the cell is near minimum — a fully charged cell prevents false BMS trips during the first shift.
Cradle showing a charging error on a new pack
The MC33 cradle communicates with the battery BMS over a dedicated contact pin before allowing charge current to flow. If that contact has oxidation or debris, the cradle throws a charging fault even on a good pack. Remove the battery, wipe all gold contacts on both the pack and the cradle slot with a dry cloth, then reseat firmly. The error clears once the BMS handshake completes — the cradle LED should switch from amber fault to solid charging within 10 seconds of reseating.
Scanner losing wireless connection during rapid scan bursts
During a fast scan burst, the imager and the Wi-Fi radio draw current simultaneously. If the cell voltage sags under that combined load, the radio drops its association before the battery protection circuit actually trips. This is a voltage-sag issue, not a range or network issue. Check battery voltage in the MC33 device diagnostics menu — if it reads below 3.4V under load, the cell is the cause. A fresh, fully charged pack eliminates the sag and keeps the radio connected through continuous scanning.