The best analysis I have seen is from Navigant Research which implies they have a source within Panasonic for cell cost.
Right now cell cost is estimated to be $180 per kWh.
Pack cost at $221 per kWh.
Gigafactory reducing cell prices by 30%.
Model 3 needs at least 48 kWh to get 200 mile range.
$126 per kWh cell cost in 2017 plus $41 per kWh for packaging in pack assuming this is not reduced. Probably will but we don't know.
$167 x 48 = $8016 battery pack for Base Model 3.
$221 x 85 = $18,785 for current 85 kWh battery.
Assuming 28% gross margins, the battery represents ~32% of the cost for the base 85 kWh car and about 25% of the average 85 kWh Model S. Which is the estimate Tesla Chief Technical Officer JB Straubel has stated publicly.
I have read a BMW 3 Series glider cost is $22k. Don't know if Tesla can achieve that cost given scale in 2017.
Tesla has not said anything publicly about drive unit cost that I have read. And since no one else is producing similarly powerful electric drive units on the Model S scale much less Model 3 we just don't know.
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As for $9000 for the 85kWh battery? Sorry I could not agree on this even though I have no inside knowledge myself. There are 7104 cells in this alone plus if you have seen inside how complex the assembly is - you'll see that it could 3-4 times as much.
The cost of the battery packs can not be $36k on a $81k car with an ASP of $106k and gross margins of 26%-28% Tesla has officially stated.
A writer on greencarreports.com has switched his S 60 battery for an 85 kWh battery. Retail price on the 85 kWh battery pack is $44,464. For every new pack they sell means they can not sell one new Model S 85. So they have to markup the battery to make a profit similar to selling the entire car.But they gave him an acceptable amount on his 60 kWh battery trade in.
http://www.greencarreports.com/news...-battery-upgrade-from-60-kwh-to-85-kwh/page-3