Large format battery cells will slowly gain a foothold on the automotive EV market in the coming years. Companies such as LG Chem, A123 Systems, and EnerDel have been hard at work developing the large format automotive specific batteries, but Tesla still insists that the laptop format, as used in their Roadster, is the best thing going right now.
According to Tesla, the laptop battery offers proven performance at an affordable price. With mass production of this type of battery ongoing for several decades now, the technology has advanced beyond that of current large format batteries. As Tesla has indicated, the mass economies that surround laptop batteries have increased competition, driven technological advances, and reduced prices making them perfectly suitable for cars.
The decision to stick with the laptop format for the upcoming Model S has met some disapproval. According to large battery format supporters and producers, this type of battery offers the distinct advantage of longevity and durability in the automotive applications. The laptop format has not seen extensive testing inside an automobile. This format also suffers from a very limited number of discharge and recharge cycles compared to the large format style.
However, Tesla has their reasons for sticking it out. Currently, the laptop format has better energy density then the newly developed large format batteries. The increased energy density leads to higher range and more output from a comparatively sized battery pack.
Several other automakers such as Chevy and Nissan and Mitsubishi have put their bets on the large format battery with their EVs, but Tesla has decided to take a proven path. At some point, the energy density of the large format battery is expected to surpass the laptop format, then Tesla may decide to make the change, but until then laptop format it is.
Source: Green Fuels Forecast