Hey Bazaki, first off, I must apologise if I am wrong, but I have been thinking this and feel I must say it, so sorry if I am wrong and pointing finger in wrong direction...but
Your friend, is he a member here on the forum? Does he read it? Or any RC or E-bike forum and
did he build the bike by himself or with help from you or someone else?
If he is not a forum member or other regular RC or LiPo user, then as far as I can see the finger of blame here points at who ever helped him build the bike. If he used LiPo totally of his own choosing without any help from a third party, then it is his own fault. Otherwise whoever helped and advised him should shoulder some of the blame
Since I have been involved in E bikes, alittle over 1 year now, I have helped build 4 different bikes for others, plus 3 of my own. 5 LiPo powered, one Headway, and one dewalt drill packs.
To every person that comes to see me about a bike, first I let them ride mine on low power, then if that does not scare them enough, on full 100 volt 80 amp high power.
I then show them what I do to charge my pack. usually followed by a deliberate overcharge and burning of a dud LiPo cell or two, plus You tube videos etc
LiPo is not for most people, and it sounds very much like your friend had no idea about LiPo at all to do what he did. I get worried enough leaving my packs alone, disconnected from the bike or any current drain for a couple of weeks. To leave them that long is just plain stupid....or totally ignorant of the facts of LiPo use
Again sorry if the build had no input from you, but it is down to all of us to help prevent this happening on Ebikes and a house getting burnt down and someone killed. What would have happened if the neighbour had not seen the smoke, fire had started at night etc etc
Mongoose frame, Fox F100 forks,26x2.3 tyres
100V 20Ah LiPo
Lyen 18 FET 65 Amp,5304 in 26 inch Mavic rim
To illustrate the vain conceit that the universe must be somehow pre-ordained for us, because we are so well-suited to live in it, he mimed a wonderfully funny imitation of a puddle of water, fitting itself snugly into a depression in the ground, the depression uncannily being exactly the same shape as the puddle."
-- Richard Dawkins, in "Lament for Douglas" (14 May 2001)