The decent China guy's that have good custom/hot battery experience - Cohnis/Risun have a very decent combiner/blender tech. I have their original 40A which has worked reliably for me over 2yrs now. Thes guys also claim to have 80A and 120A versions that I have not had occasion to buy/evaluate yet - these guys have at least 2 hats - connhis motor - and risunmotor - a friend of mine has bought (2) Molicel 72V batteries from them to complete his CYC Ripper Build stiff - my friend is still Pissed with me - with every upgrade he does - every time he still gets dusted by my Rion Scooter - and that gives me that one more ride on my Rion that I come back alive from.