The hardware upgrade consists of 2 improvements to the electronics of the Model S’ battery pack. The first improvement is the replacement of a standard fuse to an “advanced smart fuse” which enables the monitoring of current to the millisecond, and makes it possible to cut the power with “extreme precision”.
The second improvement is the replacement of the main pack contactor to use Inconel instead of steel. Inconel is a space-grade superalloy well suited for extreme high temperature environments.
When first announced, Tesla CEO Elon Musk said that “in appreciation of our existing P85D owners”, the retrofit will be offered at $5,000 + labor, which should be below the $10,000 retail on new vehicles. Through the new pre-order page, the company confirms the price of $7,500 for the retrofit.
Tesla also says that owners choosing the upgrade will have their vehicle badge updated with an underline: P85D.
Owners need to place a $500 deposit to reserve the retrofit and Tesla will make them available in “Q4”. The upgrade will first be performed at Tesla’s Fremont factory, but the company says it will expand to other service centers shortly after.