... enviromental friendly 3, different material to choose 4, 18mmX65m 18650 Lithium iron phosphate battery :1, long lifespan2, enviromental friendly3, ... different material to choose4, 18mmX65mBATTERY MODEL 18650 LiFePo4 BATTERY WEIGHT(g) ≤35 POWER DENSITY(W/kg)≥ ... 0.0165 POWER(W) ≥40 LIFESPAN(1C) ≥3000BATTERY MODEL 18650 LiMn2O4 BATTERY WEIGHT(g) ≤42 POWER DENSITY(W/kg) ≥ ...