evboy wrote:why does it matter. lithium is lithium??
Lithium is only a part of the picture. A123 in 2014 uses Lithium iron (ferric) phosphate (LFP for short) while LG in 2015+ use Lithium Nickel Manganese Cobalt (NMC). They result in different voltages, about 3.2V per cell for 2104 vs 3.7V for 2015+. Probably due to different voltages while having same energy capacity, fewer cells are needed for 2015+ to achieve ~400V needed, and the over all capacity is decreased from 20.1 kWh in 2014 to 18.4 kWh in 2015+.
Because of different chemistries, internal resistance of 2014 is probably lower. This is probably why 2014 can generate 400 ft-lb of peak torque using more current while 2015+ can only generate 328 ft-lb. Because of current limit, 2014 with 2015+ battery will probably need to "detune" the peak torque.