Photos: Munro & Associates
Sandy Munro of Munro & Associates continues to tear down a Tesla Model S Plaid, and this time the battery pack, onboard charger, and DC-DC converter were analyzed. The automotive expert is amazed at the manufacturer's architecture and foresight, calling the battery pack an engineering masterpiece.
The first thing that catches your eye when looking at the Model S Plaid battery pack is the mica shield that is bolted to the steel frame. Perhaps this was done because China now has strict fire safety requirements for electric vehicles, so some companies have begun to install a mica shield on the battery. Tesla probably did the same, though Sandy cannot be fully sure.
Sandy and Sr. Benchmarking Consultant, Lead at Munro & Associate Ben Lindamood removed the mica to take a closer look at the battery pack. In the area of concentric welds, you can see that Tesla installed an additional plate to further bolster the rigidity of the battery pack. In addition, there is a gap between the plates and the pack itself, which is left so that in the event of a collision, there is room for metal deformation, which will avoid damage to the battery.
Tesla uses casting parts to separate the battery modules, of which there are five. These parts not only separate the modules but also perform other important functions in the package. The internal castings are made in two different styles, due to the different mounting methods Tesla uses to hold the battery to a body in white. There are also some castings on the outside, which are needed in order to reduce the total number of parts used and effectively place everything that is needed there.
In the Model S Plaid battery pack, Tesla uses 18650 battery cells, the same as the previous Model S. Such cells were not chosen without reason; due to the fact that during operation, especially in track mode, 18650 cells emit less heat than larger batteries, there were ideal cells for the ultra-performance sedan.
Tesla has changed the battery architecture from what it was originally. There used to be two modules in the front of the battery, but now there's only one that houses the onboard chargers, allowing for more space for the battery cells, which are more in the Model S Plaid than in the previous Model S. The 85-kilowatt battery pack used to have 7,104 cells, but now thanks to the extra space added, the Plaid has 7,920 battery cells, totaling 100 kilowatts. Previously, the battery pack had an efficiency of 157-watt hours per kilogram, and in the Plaid it is 181.5-watt hours per kilogram. Thus, the battery can receive more charge with less weight.
The onboard charger and DC-DC converter for Model Y and Model S Plaid appear architecturally very similar at first glance, which is due to the fact that Tesla often uses the same components for different models in an attempt to reduce production costs. In addition, Model S Plaid uses fewer small and insignificant components and materials, resulting in a total savings of about 3 pounds in weight and therefore lower manufacturing costs. Sandy points out that Model 3 and Y units always had room for additional fuses, but they were never inserted; however, this was done on Model S Plaid, which is a stunning demonstration of how the company already had plans for this a long time ago. Also, the number of transformers has been increased to four from two in Model Y, indicating that they are doing something with the power that goes through there. However, more details about this are yet to be revealed.
Ultimately, all changes to the Model S Plaid battery pack are aimed at increasing range and efficiency. Meanwhile, the overall architecture is aimed at reducing production costs.
© 2022, Eva Fox | Tesmanian. All rights reserved.
We appreciate your readership! Please share your thoughts in the comment section below.
About the Author
Eva Fox joined Tesmanian in 2019 to cover breaking news as an automotive journalist. The main topics that she covers are clean energy and electric vehicles. As a journalist, Eva is specialized in Tesla and topics related to the work and development of the company.