With the increasingly strict standards regarding fuel economy and emissions, auto manufacturers have been making plenty of advancements in automobile technology. Over the last five years, the internal combustion engine [ICE] has undergone more change than in the last twenty. Subtle control changes and mechanical adjustments have made the ICE more efficient than ever.
The latest advance in efficiency is the Hybrid Electric Vehicle [HEV], which began to see widespread use in the late 90’s. Unfortunately, producing vehicles that meet the latest and upcoming standards is proving to be both technologically challenging and expensive.
Consumers will find that HEVs are typically thousands of dollars more expensive than their gasoline-powered counterparts, but are assured that they’ll recoup most or all of that extra expense in a couple of years’ driving. The reason for the extra expense is the expensive components that go into these high-technology HEVs.
Batteries and motors are made from rare elements that make for more efficient power use, but are also high priced. The electronic controls on HEVs are also some of the most complicated, and expensive, ever devised. For example, at one point in Toyota Prius’ history, the retail price for the major hybrid components including the battery pack, motor, and inverter / converter, worked out to more than the price of the vehicle.
Some claim that hybrid vehicles cost companies more than they make selling them, but Toyota, Ford, and other automakers are working to reduce the component costs to make the vehicles more profitable.
Toyota Motor Corporation, instead of switching to Lithium-ion [Li-ion] battery packs, which are more expensive, was able to make its current Nickel-Metal Hydride [NiMH] battery packs more efficient. They did this by changing the shape of individual cells from cylindrical to flat, and modified the case to improve cooling and lifespan. Toyota also switched from 500 V to 650 V, a decision that produced “a host of benefits,” says Justin Ward, advanced power-train program manager at the Toyota Technical Center. Toyota was able to reduce the size of the drive motor without sacrificing performance. This small change reduced the amount of copper needed in the motor assembly, and therefore the cost of the component.
The use of rare-earth metals is another highly expensive component in HEV technology, such as in the drive-motors. Dysprosium, when added to magnet material, increases the heat-resistance and lifespan of the drive motor. Most manufacturers are working hard to reduce or eliminate their need for such expensive materials.
Ford Motor Company, in further developing its hybrid-drive technology, made improvements to the cooling system design, reducing the need for the heat-resistant dysprosium. Their supplier, Hitachi, also made their process more efficient, yielding the same heat resistance while using less dysprosium. Changes like these enabled Ford to cut about 30% of the cost from their HEV models.
As manufacturers improve their processes and make advances in HEV technology, driving a green vehicle won’t be nearly as expensive in the near future.