Last weekend for the first time I actually ran out of battery, I have two battery meters, on the left on handle bars with the speedo there is a bar graph, with 5 segments, and on right with the key switch there are three LED lights, why it has two not a clue, but it seems the LED lights are the important one on the right, as soon as last light goes out, assistance stops.
I have a 48 volt 12 Ah battery, and was cycling Shrewsbury to Welshpool using google maps, with a few wrong turns, so did around 22 miles before it switched off, I then did around 2 miles without assistance, when it then allowed me to re-engage the electric assistance so did so only at number 2 of 5, and it did a further 2 miles before I arrived at the pub I had arranged to meet wife at and put bike in the car boot.
The route had some steep hills, so I had used the electric a lot, I am sure had I used the main road, it would not have run out, but then I would have likely tried to do last 8 miles home up golfa bank and still run out before getting home.
I could carry my battery charger, and I am sure I could recharge it in the pub, but on charge there is simply a green/red LED that turns to green once charged, unlike my wife's bike which has LED's on the battery pack to show state of charge, I did monitor charge once
but it was not completely flat, but seems likely needs at least 3 hours to fully charge, but 2 hours would give a good amount. So stopping for a meal would give it a good chance to re-charge.
I had expected the motor to slowly give less and less assistance, but that was not the case, there was a switch off point. I know with my wife's bike (Bosch mid motor) it is claimed to switch off traction but still allow one to use lights. Did not try light on my bike, but lights don't work until on button pressed on left, and the on button would not engage once battery was discharged, so assume both light and horn would also stop working?