About this replacement
Motorola MC21 Series — 3.7V Li-ion Replacement Battery (82-105612-01)
This 3.7V, 2300mAh Li-ion battery replaces the original pack in the Motorola MC21, MC2100, and MC2180 handheld barcode scanners. These are compact mobile computers used in retail, logistics, and warehouse pick operations. It cross-references OEM part numbers 82-105612-01, BTRY-MC21EAB0E, and 82-150612-01.
- MC21, MC2100, MC2180 compatibility: All three models run the same 3.7V single-cell architecture with an identical connector and BMS handshake protocol. One battery fits the full MC21 platform without modification.
- Bench tested on actual hardware: We ran this pack on an MC2100 unit and monitored BMS communication through the cradle charge cycle. The protection circuit responded correctly to charge termination and showed no false overcurrent trips during rapid scan-trigger sequences.
- First-shift preparation: After installing the new pack, seat the scanner in its charging cradle and complete a full charge cycle before deploying it on the floor. Scan-trigger inrush current peaks when the cell is near minimum — a pre-charged cell prevents the BMS from tripping on that first-shift surge.
Cradle showing a charging error on a new MC21 pack
The MC21 cradle reads battery state through gold pogo pins on the pack's contact rail. Oxidation or residue on those contacts raises resistance enough that the cradle reports a fault rather than beginning charge. This is not a defective battery — it is a contact issue. Wipe the pack's gold contacts and the cradle's pins with a dry lint-free cloth, reseat the scanner firmly, and the cradle should begin the charge cycle within 10 seconds.
Scanner loses wireless connection during rapid scan bursts
The MC21 draws current simultaneously from the imager and the 802.11 radio during a burst-scan sequence. On a degraded or deeply discharged cell, this combined inrush causes a brief voltage sag below the BMS cutoff threshold, which drops the radio before the battery fully trips. The scanner appears to scan but stops transmitting data. Charge the pack above 3.6V before the shift starts — the sag margin is narrow enough that even 20% state-of-charge makes the difference.