Thanks for the replies.
I am often torn between it looks like a good idea and as MithcJi suggests there are better options.
It is really hard to beat government rebates and mass production. Not to consider that they know what they are doing.
Current specs appear to be along the lines of:
48 200AH LiFeP04 cells (Thundersky more or less 144V 200AH)
Elithion BMS
Manzanita Micro charger
Netgain Impulse 9" motor
to power a Factory 5 Type 65 Coupe (a kit car): http://www.factoryfive.com/coupehome.html
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Total cost looks like under...