Battery management systems are being designed to meet the performance, life and warranty goals of both batteries and their monitoring and management systems. "Carmakers need to understand how operating limits vary in battery life through testing and modeling, followed by the development of sophisticated algorithms to track and predict various parameters such as state of charge and health status over the life of the battery, "comments Rizzoni.
In order to expand the range of battery operation and reduce costs, some researchers are designing and testing new chemical batteries and subsystems. Advanced chemicals can allow batteries to run through higher temperature extremes, last longer, and reduce weight and cost. Other efforts are being made to reduce the cost of auxiliary systems, such as cooling, to further reduce the total cost of the battery system.
2. Reduction of personnel and overload
The two main benefits in reducing the size of an internal combustion engine are thermodynamics and mechanics. "From a thermodynamic point of view, engine operation will move to higher loads, where engine efficiency is higher," says Rizzoni. "From the mechanical point of view, the positive aspect lies in the reduction of the friction in the piston units, along with the reduction of the number of cylinders."
Reduced engines are lighter than conventional engines, thus reducing vehicle mass and improving vehicle fuel consumption. Turbocharging recovers the energy of the exhaust gases to increase the load inducted, therefore increasing the ratio of power-to-displacement. "A small, turbocharged engine has the potential to have the same or better performance than a normally aspirated, non-aspirated engine with the advantage of a significant increase in fuel efficiency," says Rizzoni.
3. Advanced Combustion Modes
Engineers are working to increase the efficiency of internal combustion engines by developing several advanced combustion modes. One of these modes is called (homogeneous charge compression ignition) HCCI. In the HCCI combustion, a highly homogenized mixture of air, fuel and combustion products from the previous cycle is self-ignited by compression. "This mode of combustion aims to combine the advantages of modern diesel and gasoline combustion processes, namely low emissions and high efficiency," says Rizzoni.
Another research trend focuses on ways to recover the energy that is normally dissipated through the refrigerant and exhaust systems of automotive powertrains using innovative waste heat recovery devices. These systems can convert thermal energy into mechanical or electrical energy, thus increasing the overall efficiency of the vehicle. Organic Rankine cycle systems, thermoelectric systems, turbocompounding and recovery thermal management systems have the potential to significantly increase engine efficiency.
A smaller but still significant aspect of fuel efficiency research is called "intelligent energy management". "This ability to more intelligently control ancillary loads in a vehicle - such as the alternator or power steering, etc. - will also help improve gasoline consumption," says Rizzoni. "With smarter control of these loads and the addition of stop-start technology there can be significant increases in fuel economy, with little or no increase in the total cost of the vehicle."