About this replacement
Intermec CN50 / CN51 — 3.7V Li-ion Replacement Battery (318-039-001)
This 3.7V Li-ion battery at 3900mAh (14.43Wh) replaces the original pack in the Intermec CN50 and CN51 rugged handheld computers. Both devices run the same battery rail, connector, and BMS handshake, so one SKU covers the pair. It slots into the standard battery bay without tools or configuration.
- CN50 and CN51 shared platform: Both scanners run the same 3.7V cell architecture, dock connector pinout, and BMS communication protocol. Intermec carried the same battery specification across both generations, which is why OEM cross-references AB24, AB25, 318-038-001, 318-052-001, and 318-052-011 all map to this pack.
- Bench tested on actual hardware: We cycled this pack through repeated scan-trigger and Wi-Fi polling loads. The BMS held voltage steady through combined inrush events and tripped cleanly at the low-cell threshold without false cutoffs during burst scanning sequences.
- First-shift prep for pick-and-pack operations: Place the scanner in its cradle for a full charge cycle before the first shift. Scan-trigger inrush current peaks when the cell is near minimum. A fully charged cell prevents a false BMS trip mid-shift when scan frequency is highest.
Cradle showing charging error on a new CN50 battery pack
New packs sometimes trigger a charging fault on the CN50 cradle even when the pack itself is fine. The most common cause is contact resistance at the dock pins — manufacturing residue on the gold contacts raises resistance enough that the cradle misreads charge state. Wipe the battery contacts and the cradle pins with a dry lint-free cloth, then reseat the unit firmly. If the error clears within 30 seconds of reseating, the pack is good and the contacts were the cause.
CN50 dropping wireless connection during rapid scan bursts
The CN50 runs its 802.11 radio and scan-trigger motor from the same cell. During a rapid scan sequence, the combined current draw from the imager and the radio transmit pulse can cause a momentary voltage sag. If the cell is below roughly 3.5V, that sag is deep enough to interrupt the wireless stack. The radio drops and takes several seconds to reassociate. Keeping the battery above 3.6V during a shift — via mid-shift cradle docking — keeps the combined draw inside the BMS headroom and prevents the drop.