HandHeld Dolphin 7900 Replacement Battery 7.4V 3400mAh

HandHeld Dolphin 7900 / 9500 / 9550 / 9900 — 7.4V Li-ion Replacement Battery (200-00591-01)

This is a 7.4V 3400mAh Li-ion battery for the HandHeld Dolphin 7900, 9500, 9550, and 9900 rugged mobile computers. These devices are used in warehouse pick-and-pack, retail inventory, and asset tracking operations. The pack slots into the same battery bay as the original and communicates with the device BMS over the same contact array.

• Dolphin 7900, 9500, 9550, and 9900 compatibility: All four models share the same 7.4V battery bay, connector pinout, and BMS handshake protocol. One pack covers the full platform without any wiring or adapter differences.
• Bench tested on actual hardware: We cycled this pack through barcode scan bursts combined with active wireless polling. The BMS held stable across repeated trigger-inrush events and did not trip on cold-start draws.
• First-shift preparation: After installing a new pack, place the Dolphin in its charging cradle and run a full charge cycle before the first pick-and-pack shift. The scan trigger inrush current peaks when the cell is near minimum voltage — a fully charged cell prevents false BMS cutoffs during the first hour of operation.

Cradle throwing a charging error on a new pack

Dolphin charging cradles use spring-loaded contacts to communicate charge status. If those contacts have oxidation or debris from a worn-out pack, the cradle reads elevated contact resistance and flags a fault rather than starting a charge cycle. Wipe the gold contacts on the bottom of the new battery and the matching pins inside the cradle with a dry lint-free cloth. Reseat the device firmly until you hear it click into place. The cradle should begin charging within 10 seconds and the amber LED should appear steady.

Scanner losing wireless connection during rapid scan bursts

On the Dolphin 9500 and 9550, the radio transmitter and the scan trigger both draw current simultaneously during a rapid scan sequence. If the cell voltage sags below 6.8V under that combined load, the BMS briefly reduces output to protect the cell — the radio drops its connection before the scanner shows any low-battery warning. This is more common with aged packs that have lost capacity through shallow cycling. A replacement pack at full charge maintains voltage above 7.0V under the same combined load, keeping the radio link stable through the burst.