Technology

No "Free" Fuel For Electric Vehicles

We take for granted that a gasoline engine burns gas, but forget that it is also burning air. At a 14 to 1 air/gas ratio, over 90 percent of the fuel comes for "free" from the atmosphere. In an electric powered vehicle, all the energy must be stored in the batteries.
Given the poor energy density of batteries, an electric vehicle must be extremely efficient.
The largest power loss in any vehicle is due to aerodynamic inefficiency. It is obvious that we need a low CD(coefficient of drag) and a streamlined shape. But what is often overlooked is vehicle cross sectional area. The larger the vehicle cross sectional area, the more power it takes to push it.

The X-Cycle Solution

The X-Cycle takes a unique approach to efficiency. By placing the passengers directly behind the driver (tandem seating) the cross sectional area is halved. This is a 2x improvement in efficiency.
With tandem seating, a single rear wheel naturally sits behind the passengers. This helps create a tear drop shape for good aerodynamics.

Having three wheels makes the x-cycle a motorcycle. As a motorcycle, the legal hurdles required to enter production are much lower.

Implementation

Frame: Steel, Aluminum and Carbon fiber
We need to keep the X-Cycle frame as light as possible. Carbon fiber and Aluminum offer obvious weight advantages, but at sever cost penalties.

We have concluded that the production, maintenance and repair benefits of steel outweigh the competition. In addition through innovative design and production techniques we can further reduce the X-Cycle weight.

Motor: AC, DC, DC SepEx, Brushless DC
After much testing we have concluded that an AC motor is necessary for a production EV. AC Motors have better reliability and a higher efficiency. The cost of an AC Motor is slightly more than a DC Motor, but these costs are reducing rapidly. In addition, the extra efficiency of the AC motor allows a smaller and lighter battery pack; which offsets the extra cost of the AC motor.

The AC Motor has no brushes to wear out or reduce efficiency and inherently allows regenerative braking.

Batteries: Lead and Lithium
The first X-Cycle prototype had lead acid batteries. We were originally convinced that we could make the lead acid batteries work. Under many conditions they did work fine. However, under heavy acceleration and hill climbing, lead acid batteries have sever limitations. Today’s consumers have extremely high performance and reliability expectations that can not be met by lead acid batteries.

 The X-Cycle now uses Lithium batteries. We see significantly better high current (acceleration and hill climbing) performance, lower weight and longer life. The cost is still high, but costs are reducing over time and we see many new manufacturers and new technologies emerging. We are confident that a practical price point is near. In fact, due to the longer life time of lithium batteries, the higher initial expense actually results in a lower life time expense even at today’s prices.

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