The Wall Street Journal recently ran a report on how the decline in the value of the U.S. dollar against almost all other currencies is prompting car makers to take a new look at exporting vehicles built here. Almost as an aside deep within the article it was mentioned that Tesla has decided to shift production of their battery packs from a factory in Thailand to their home base in San Carlos California. According to Tesla VP Darryl Siry, the exchange rate wasn't the primary reason for the change. The logistics of shipping 1,000lb battery packs halfway around the world were the primary concern. The energy storage system represents a significant portion of the cost of the car and having that sit on a boat from half way around the world just didn't make sense.
The 6,831 lithium ion cells in each pack are sourced from suppliers in Taiwan and will now be shipped directly to the U.S. where the packs are being assembled. Cars for U.S. delivery are being shipped from England sans energy storage system which gets installed when the cars land here. Once the cars arrive in the U.S., the battery is installed. Similarly, when European deliveries begin next year, the packs will be installed locally prior to delivery. With the current slow assembly rate, the packs are being assembled at the San Carlos headquarters. As production ramps up, they will likely move that process to a larger facility.
[Source: Wall Street Journal, Tesla Motors]