Dolphin 7300 Replacement Battery 3.6V 2700mAh Ni-MH

Dolphin 7300 / 7400 Series — 3.6V Ni-MH Replacement Battery (200-00552)

This is a 3.6V, 2700mAh Ni-MH battery for the Dolphin 7300, 7400, 7450, and HH-7400M handheld barcode scanners. It replaces OEM part numbers 200-00552 and 200-00589. These scanners are used in retail and warehouse pick-and-pack operations where scanner downtime directly stalls throughput.

• 7300 / 7400 series platform fit: The 7300, 7400, 7450, and HH-7400M share the same battery bay dimensions, connector pinout, and BMS handshake protocol — one cell pack covers the full range without modification.
• Bench tested on actual hardware: We cycled this pack through the 7400's BMS on the bench. The protection circuit responded correctly to scan-trigger inrush and wireless radio draw, holding voltage without tripping the low-cell cutoff under combined load.
• First-shift cradle conditioning: After installing a new pack, seat the scanner in its cradle for a full charge cycle before sending it to the floor. Scan-trigger inrush current peaks when the cell is near minimum charge, and a fresh-from-box Ni-MH cell can trip the BMS cutoff on the first heavy scan burst if deployed uncharged.

Cradle showing charging error on a new pack

Ni-MH cells fresh from storage can sit at a resting voltage that the Dolphin cradle's charge controller reads as a fault condition rather than a discharged pack. The dock checks cell voltage on contact before initiating a charge cycle — if the reading falls outside its expected window, it flags an error instead of charging. Wipe the battery contacts and cradle terminals with a dry cloth and reseat the pack firmly. If the error persists, remove the pack, wait 10 seconds, and reseat — this resets the dock's contact-detection handshake.

Scanner losing wireless connection during rapid scan bursts

On the 7400 series, the radio transmitter and the scan trigger fire simultaneously during fast-paced scanning — the combined inrush can pull voltage down momentarily if the cell is partially depleted. The BMS interprets this voltage sag as a low-cell event and briefly cuts power to non-essential subsystems, which drops the wireless link. The fix is to avoid running the pack below roughly 3.3V under load — if the scanner is losing connection mid-shift, return it to the cradle before the shift ends, not after.