Symbol MC3100 Barcode Scanner Replacement Battery 3.7V 2500mAh

Symbol MC3100 / MC3190 Series — 3.7V Li-Polymer Replacement Battery (82-127909-02)

This 3.7V, 2500mAh Li-Polymer battery replaces the original pack in Symbol MC3100 and MC3190 series handheld barcode scanners. It matches OEM part numbers 82-127909-02, BTRY-MC31KAB02, and BTRY-MC3XKABOE. Direct fit for MC3190, MC3190G, and MC3190-G13H02E0 variants without modification.

• MC3100 and MC3190 platform fit: These models share the same battery bay dimensions, connector pinout, and BMS handshake protocol. One pack covers the full platform — the charge controller in each unit reads cell state the same way across all variants listed.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on the MC3190 platform. The BMS reported correct cell voltage at all charge states, and the scanner's battery indicator tracked accurately from full to cutoff without error flags.
• First-shift cradle charge: After installing this pack, seat the scanner in its charging cradle and run a full charge cycle before deploying. The scan trigger draws its highest inrush current when the cell is near minimum — a fully charged cell prevents false BMS trips during the first pick-and-pack shift.

Cradle showing charging error on a new pack

MC3100 and MC3190 cradles are sensitive to contact resistance at the battery terminals. A new pack that hasn't been seated firmly or has factory residue on the gold contacts will trigger a charging fault on the dock LED. Wipe the pack contacts with a dry lint-free cloth, press the scanner firmly into the cradle until you hear the click, and check that the amber charge light comes on within 10 seconds. If the error persists, check the cradle pins for debris — bent or dirty cradle contacts are a separate fault that a new pack won't fix.

Scanner losing wireless connection during rapid scan bursts

On the MC3190, the wireless radio and the scan trigger both pull current at the same moment during a high-frequency scanning run. If the cell voltage sags below the radio's minimum operating threshold — typically around 3.2V under combined load — the wireless stack drops before the scanner itself powers off. This looks like a network dropout but the root cause is voltage sag under combined draw. A pack that holds closer to its rated 2500mAh capacity will maintain voltage headroom across longer bursts. If dropouts occur mid-shift, check that the pack is starting each shift at a full charge rather than topped off from a partial cycle.