Commercial Fixed Wing
Flight Crew Air Transport Pilot (ATP)
Time Pressure; Distraction; Communication Breakdown; Workload
Aircraft Equipment Problem Less Severe; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Air Traffic Control Issued New Clearance; Air Traffic Control Provided Assistance; Flight Crew Diverted; Flight Crew Landed As Precaution
Aircraft
During cruise; we were informed by flight attendants of a fire in the aft galley area. I immediately [advised ATC] and requested a divert to the nearest appropriate airport. We began a descent and followed ATC heading and altitude instructions toward our diversion airport. Flight crew put on quick don O2 masks and established communications per our memory item procedures; then accomplished the QRC for Cabin Smoke/Fire.At this point we continued with the following actions: We verified the seat belt sign was on and made a PA to be seated and remain seated. We checked with the FA in back to get more information in order to better evaluate the situation; and communicate our plan to divert and expected ETA. We continued to coordinate with ATC including giving fuel and souls on board; and ascertain the weather and field conditions; set up navigation; consider performance and our overweight landing status; and continued with the checklist in the QRH.All of these listed actions were done concurrently as information was sought and processed; and prioritized. For example; during times I; as the captain; was talking in back to the FAs; further ATC clearance would be received by the flying FO. At these times; both pilots would miss some information until we had a chance to end those conversations and get back together. The FO received the localizer frequency for runway and tuned both radios while I found out the fire was considered extinguished by the FAs. But neither one of us was immediately aware of the others new information; nor aware the other pilot was missing that information. Continually seeking new information and reevaluating the situation keep us from missing things or getting behind; even when we didn't know what questions to ask.Concurrently also referred to the checklist; where the normal and reasonable interruptions from ATC and FA on the plane; as well as monitoring the airspeeds and altitudes and finding checklists and setting the altimeter and scanning; bugging airspeeds and discussing autobrakes and other tasks make it hard to complete the checklist without a concerted and focused effort; and frankly impossible to complete uninterrupted.Somewhere during the descent/approach we were informed that the fire was from a flight attendant portable sales device battery and believed to be out / no longer smoking. We executed a normal landing; cleared the runway; shut the engines down; and had local fire and rescue use their ladder to access the aft left side aircraft door nearest the location of the reported fire. The fire was determined to be out and no longer a threat by the fire department. The fire crew deplaned and we started engines and proceeded to an adjacent gate.We; as the two pilots; did debrief each flight attendant after the event and I as the captain debriefed the entire crew together. My understanding is that the device was noted to be very warm by a FA while they were in the aisle with a cart offering entertainment devices for rent. The FA carried the phone to the aft galley where she noted smoke and sparks coming from the device; and began to fight the fire. A Halon extinguisher followed by a water extinguisher followed by another Halon extinguisher brought from the front of the aircraft; along with a PBE breathing hood; was used to fight the fire. Per their procedure; they are supposed to then place the object in an empty oven. But the ovens were in use and hot; so they put the now cool device in an empty trash bid in the galley. Battery overheat of FAA approved device not connected to or a component of the actual aircraft.
The iPad JeppFD Pro app did not have plates for [our divert airport] but we were able to zoom in on the iPad Jepp map page to see a visual of the runway layout; runway lengths; and airport elevation. I requested runway in use and localizer frequency/inbound course; set the Nav radios/MCP courses and inputted ZZZ on the FMC Fix and Legs pages with a runway centerline extension drawn for visual aid in finding the field. The weather was CAVU with light winds. We were vectored north of the field to accommodate the descent.The fire event was initiated [within]; and limited to; the FA's portable credit card sales device.
Air carrier flight crew reported diverting to nearest suitable airport after a portable credit card device caught on fire in the cabin.