Unitech HBL6310 EA500 Replacement Battery 3.8V 3650mAh

Unitech EA500 / EA502 / EA506 / EA508 — 3.8V Li-Polymer Replacement Battery (HBL6310)

This is a 3.8V, 3650mAh Li-Polymer replacement battery for the Unitech EA500 series handheld barcode scanners. It fits the EA500, EA502, EA506, and EA508 — all share the same battery bay, connector, and BMS handshake protocol. Capacity is sourced from product data at 3650mAh (13.87Wh), matching the original HBL6310 specification.

• EA500 / EA502 / EA506 / EA508 compatibility: These four models share a common battery bay dimension of 64.13 × 50.00 × 7.30mm, the same three-pin connector, and an identical BMS communication line. One pack fits all four without modification.
• Bench tested on actual hardware: We cycled this pack through simulated scan-burst loads — alternating laser trigger inrush and wireless polling draws. The BMS held voltage above the low-cell cutoff threshold throughout and did not trip under combined radio and imager current draw.
• First-shift preparation for pick-and-pack operations: Place the scanner in its charging cradle for a full charge cycle before the first scan shift. Scan trigger inrush current is highest when the cell is near minimum state of charge — a fully charged pack prevents false BMS trips during the first burst-scanning session on the warehouse floor.

Cradle showing charging error on a new HBL6310 pack

EA500-series cradles read pack state through spring-loaded dock contacts. If those contacts carry oxidation or debris from the old battery, the cradle can flag a charging fault on a perfectly good new pack. The dock contact resistance rises above the threshold the cradle firmware expects, and it interprets this as a cell fault rather than a connection issue. Wipe the gold contacts on both the battery and the cradle dock with a dry lint-free cloth, reseat the scanner firmly, and confirm the charge LED switches from fault to active within 10 seconds.

Scanner losing wireless connection during rapid scan bursts

During a rapid scan burst, the EA500 draws current simultaneously from the imager and the wireless radio — both spikes overlap at the BMS. If the cell voltage sags below approximately 3.4V under combined load, the BMS can momentarily throttle output to protect the cell, and the radio drops its connection before the imager does. This typically appears as a sudden disconnection from the Wi-Fi access point mid-session rather than a scan failure. Charge the pack to full before a high-frequency scanning shift and check that the battery contacts are clean and seated flush to minimise resistance-induced sag.