About this replacement
Symbol MC9000 Series — 7.4V Li-ion Replacement Battery (BRTY-MC90SAB00-01)
This 7.4V 2200mAh Li-ion battery fits the Symbol MC9000 series handheld mobile computer, including the MC909X-K and MC9090-K. It replaces OEM part BRTY-MC90SAB00-01 and cross-references 21-65587-01, 82-111734-01, and related part numbers. Capacity is 16.28Wh — drawn directly from the pack specification, not estimated.
- MC9000 series platform fit: The MC9000, MC909X-K, MC9090-K, and related variants share the same battery bay geometry, contact pin layout, and BMS handshake protocol. This pack communicates cell status to the device over the same data line as the OEM unit — the scanner's power management firmware recognises it without reconfiguration.
- Bench tested on actual hardware: We ran this pack through charge, discharge, and BMS trip cycles on MC9000-series hardware. The BMS handled scan-trigger inrush at low state of charge without tripping the protection circuit, and the cradle charger accepted the pack and reported charge status correctly through all stages.
- First-install charge before pick-and-pack: After installing, seat the scanner in its cradle and complete a full charge cycle before the first shift. Scan-trigger inrush current spikes highest when the cell is near minimum — a fully charged pack on first use prevents false BMS trips that can get misread as a faulty battery.
Cradle showing charging error on a new pack
The MC9000 cradle reads the battery's contact pins to verify pack identity before starting the charge cycle. If the dock contacts on the pack or cradle have oxidation or debris, the cradle can flag a charge fault even when the pack itself is fine. Wipe the gold contacts on the battery with a dry lint-free cloth, reseat the scanner firmly, and check that the cradle's own contacts are clean. A confirmed good connection shows a solid amber charge indicator within 10 seconds of seating.
Scanner loses wireless connection during rapid scan bursts
During a rapid scan burst, the imager draw and the 802.11 radio transmit cycle overlap — combined current demand can cause a brief voltage sag on a partially discharged pack. The MC9000 radio stack is sensitive to supply voltage dipping below approximately 6.8V, which triggers a momentary radio reset that shows up as a dropped connection to the host. Starting the shift with a fully charged pack raises the cell voltage headroom enough to absorb both loads simultaneously. If drop-outs persist on a freshly charged pack, check the cradle charge contacts — an incomplete charge cycle leaves less headroom than the gauge suggests.