Symbol MC55 Barcode Scanner Compatible Battery 3.7V 2400mAh

Symbol MC55 / MC65 Series — 3.7V Li-ion Replacement Battery (BTRY-MC55EAB02)

This 3.7V, 2400mAh Li-ion battery replaces the original pack in the Symbol MC55, MC55A, MC56, MC65, and related handheld mobile computers. These devices run in retail, logistics, and warehouse environments where barcode scanning and wireless data collection run continuously across long shifts. Capacity figure is 2400mAh (8.88Wh) — confirmed from product data, not estimated.

• MC55 / MC65 platform compatibility: These models share a common 3.7V battery bay, connector pinout, and BMS handshake protocol. One pack covers the full range — the voltage rail and communication lines are identical across the MC55, MC55A, MC56, and MC65 variants.
• Bench tested on actual hardware: We ran this pack through the MC55's BMS initialisation cycle and confirmed the protection circuit communicates correctly with the host device. The BMS triggers appropriate cutoff under simulated scan-burst and wireless polling load without false trips.
• First-shift prep for pick-and-pack use: After installing, seat the scanner in its cradle and run a full charge cycle before the first shift. Scan trigger inrush current peaks when the cell is near minimum — starting from a fully charged state prevents the BMS from tripping on the first heavy burst of the shift.

Cradle showing charging error on a new pack

Charging docks on the MC55 series read contact resistance across the battery terminals before initiating a charge cycle. If the resistance reading is too high — often from factory protective coating or handling oils on the gold contacts — the cradle flags an error rather than charging. Wipe the pack's contact pads with a dry lint-free cloth, reseat firmly, and the dock should begin the charge sequence within 30 seconds. If the error persists, check the cradle contacts for oxidation and clean with isopropyl alcohol before retesting.

Scanner losing wireless connection during rapid scan bursts

During high-frequency barcode scanning, the MC55 draws simultaneously from the scan engine and the 802.11 radio — two inrush events stacked in rapid succession. If the battery's state of charge is already low, combined current draw can cause a momentary voltage sag that drops the radio below its minimum operating threshold, triggering a disconnect. This is not a radio fault — it is a load management issue. Keep the pack above 20% charge during active pick-and-pack shifts to prevent the sag from reaching the radio cutoff threshold.