Where are you finding cells for $1 each? Going rate for 18650s (new) is $180/kWH or so, which for a typical 2.6AH cell would be $1.73.
Li-Ion (and related sub-chemistries, e.g. NMC, LMO (uncommon), LCO, etc.) are 3.7V, and are higher energy density but less "safe". LiFePO4 is 3.2V, and is considered more safe, but is less common, more expensive, and lower energy density. That said they usually have high/er power density. I solder, but that's because I don't have space/money for a spot welder (at least not a quality one). Cheap spot welders aren't too good, and results are mixed. Too much power and you blow a hole in the cell, too little and you get weak connections. Cleaning up is also annoying if you need to change out a cell. I prefer to solder, with individual cell fuses for each cell (I use 30ga tinned copper wire, which blows at ~20A in a short circuit). Better is using individual glass fuses with solderable legs, which go down to 0.5A in rating, but the breaking point experimentally appears to be about twice the rating. -- Sent from: http://electric-vehicle-discussion-list.413529.n4.nabble.com/ _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
