Date: 201910
Local time of day: 1801-2400
Location: CVG.Airport, KY
Flight conditions: VMC
Light: Dusk
Aircraft: EMB ERJ 145 ER/LR
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Descent
Airspace: Class B CVG
ATC / advisory: TRACON CVG
Aircraft component: Electronic Flt Bag (EFB)
Component problem: Design; Improperly Operated
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying; Check Pilot
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Human factors: Situational Awareness; Distraction
Anomaly: Aircraft Equipment Problem Less Severe; Deviation - Speed All Types; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Became Reoriented; Flight Crew Overcame Equipment Problem; Flight Crew Returned To Clearance
Contributing factors: Aircraft; Human Factors
Primary problem: Human Factors

Narrative: I was PM (Pilot Monitoring) working with a First Officer on their first trip. We briefed and prepared to do the arrival. About midway through the flight; I realized my EFB was under 10% battery life due to a busy work day. I pulled out my spare battery to plug in; but it was out of power. The FO (First Officer) lent me his spare battery and I used it to charge during descent.ATC assigned us to cross [a point] at 11;000 feet; so we did that and leveled off. While we were waiting for our next descent; the PF (Pilot Flying) FO mentioned concerns about being at 12% battery life on the EFB and losing power during the approach. We talked about this for a moment and ATC instructed us to descend and maintain 6;000 feet. The PF set 6;000 feet. and vertical speed; beginning a descent. We used VVM (Verbalize; Verify; and Monitor) procedures.At this point; I went back to my previous train of thought and offered to give the FO his external battery back so he would have the power he needed have EFB functionality through the remainder of the flight. He grabbed the battery and plugged it in; when we received a triple chime warning and 'High Speed' from the aircraft. I quickly realized the airspeed was over 310 kts and we were descending through 9;400 feet. I took the flight controls from the FO and used the TCS (Trim Control System); manual control; to level the aircraft and slow it under 250 KIAS. I had also neglected to turn on the sterile cockpit light due to the battery distraction and did this after getting the speed under control. Afterwards the flight continued normally and there was no mention from ATC.Threats: Long leg at 11;000 feet with anticipated descent and slowdown to 250 KIAS by 10;000 feet. EFB battery life concerns after a long duty day with nearly 7 hours of flying. ATC assigning different altitude than what we expected per the STAR. LCA (Line Check Airman) working with [FO] candidate on first trip; so experience level and error commit rate is high. Errors: Decision to swap external EFB batteries during a critical descent phase; causing loss of situational awareness by both pilots. Failure to monitor/cross check by PM. Failure to actively fly the aircraft by the trainee PF. PM's poor assumption that [Line Check] FO candidate had enough experience and situational awareness to slow the descent through 10;000 feet to meet the 250 KIAS airspeed limit. [Deviation]: Crossing the 10;000 feet speed limit at 310 KIAS down to 9;400 feet followed by a brief aircraft over speed/warning.I need to be more vigilant in my monitoring duties when close to the 10;000 feet speed limit; especially after a long duty day with minimum rest the previous night. I cannot take anything for granted when working with a candidate and must not let a distraction like the EFB battery swap cause me to neglect my primary responsibilities. I should have deferred this swap to a latter; less workload intensive time. From the company's perspective; I think it would benefit us to have some better quality EFB's with a longer battery life so we are not diverted from our primary duties in an effort to charge; or 'milk' the life out of them. which lowers our situational awareness.




Synopsis: EMB-145 Captain reported being distracted by EFB battery issues and receiving a high speed warning on descent to CVG while on the SARGO three arrival.