Ever since the late 1960s, the automotive industry has steadily become a major consumer of electronics technology. Now, with the advent of hybrid and electric vehicles and driverless cars, the industry looks set to place an even greater reliance on electronic components and systems as it moves towards the EV revolution.
More or less beginning when electronic ignition replaced the distributor, electronics now accounts for a huge percentage of the on-the-road price of even the most basically equipped car.
With an initial focus on reliability and entertainment, car manufacturers quickly realised that the adoption of electronic systems could dramatically increase efficiency and safety levels. Now, all the talk is of driverless (or autonomous) and electric cars which many see as the future of motoring and which will greatly increase the electronics content of vehicles.
Big corporations – Apple and Google for example – are investing heavily in the concept of driverless cars even though recent publicity has shown that many of us are not yet convinced that being a passenger in a computer on wheels is such a good idea.
Many, however, believe driverless cars will find application in town centres or cities where it will be simple to exclude cars driven by humans.
In any case, today’s premium cars are gradually moving towards being “almost driverless”. They can park themselves, stay in a lane, brake when they sense danger, provide a 360-degree picture of their surroundings and, with some of the latest German marques, even extricate themselves from a tight parking space. All this means the use of sensors throughout the vehicle is on the increase. Recent announcements include a car seat that can analyse a driver’s perspiration to assess their alertness, steering wheel sensors that can tell if the driver has had too much alcohol before the vehicle is “allowed” to start.
Thanks to a combination of GPS, radar and a myriad of intelligent sensors, drivers of cars of the not too distant future will simply have to start the car, steer it and switch it off on arrival. But how will it be powered?
Electric Vehicles are the future – driver or driverless
Recent Government announcements here in the United Kingdom as well as other locations have made it quite clear that vehicles powered by an internal combustion engine have no place on the roads of the future. And, as of today, the only contender to replace them is electric vehicles (EVs).
Most electric and hybrid vehicles available today are variants of existing models made by traditional car companies and a number of these car manufacturers have recently established a timeline when every model they manufacture will incorporate an electric motor. These include Volvo, Jaguar Land Rover and General Motors.
These manufacturers will currently be striving to design new EV platforms and will be working alongside battery makers to develop a power source that will provide the EV a meaningful range and one that will take a charge in a matter of minutes and not the hours that most take today.
The obvious exception is Tesla which emerged as the first new “kid on the automotive block” offering a selection of all electric cars with a higher than average range. Many think this is due to Tesla’s investment in its own battery production facility.
While Tesla is the first so-called disruptive entrant to the marketplace, it will by no means be the last. A recent announcement by Sir James Dyson makes it clear that the UK’s vacuum cleaner pioneer plans to develop an all-electric vehicle by 2020. Like Tesla, Dyson has invested in battery design and manufacture and it seems likely that the Dyson car will use solid-state battery technology, regarded as the next big development over Lithium-Ion batteries currently powering electric vehicles. Solid state battery packs are said to offer many advantages. They have a higher energy density, are quicker to charge than liquid-cells, cooler while operating and potentially more powerful.
However the vehicle is powered, it will include on-board entertainment and information systems, safety systems, environmental control systems and engine management systems. And it is here that our custom device design expertise is already being applied in a variety of applications – we are the World’s leading supplier of custom devices used in Tyre Pressure Monitoring Systems (TPMS) and our application specific ICs (ASICs) are used in a majority of the systems fitted to today’s models and other sensor applications on a vehicle. Today, we are also involved in the important development of battery management systems for EV applications.
By their very nature, electric vehicles make differing demands on the electronic components industry. Not least, of course, in battery management. The power cells found under the seats of today’s EVs provide a huge amount of energy storage and, when connected together in a large pack, they deliver many hundreds of volts. Managing the charging process and providing the driver with an accurate indication of the power pack’s state of charge and state of health is essential if the driver is to know exactly how far he can travel before plugging in.
Because they are rechargeable, they present a complex electronics control application. Why? Lead acid batteries in conventional cars employ give a good indication of state of charge (SoC) by simply measuring the voltage across their terminals. However, most EV powertrain packs comprise many Lithium Ion cells which provide their state of charge “information” in a totally different way.Drivers of conventional cars are used to seeing a fuel gauge that details fuel left and a miles/kilometre range until empty. But, unlike measuring the position of a float in the vehicle’s fuel tank, determining the state of charge of a Lithium Ion battery pack means measuring the current flow over time to gauge how much energy has gone into the cell or been taken out.
In addition to state of charge calculations it is also necessary to determine a cell’s state of health (SoH). Taking care of SoC and SoH will be a battery management system (BMS) which comprises a number of devices that communicate with each other in a hierarchy to ultimately tell the driver how far he or she can travel before a recharge is needed. And this means managing each cell.You can be sure that Swindon Silicon Systems is working with customers to develop application specific components that will help control the next generation of EV power packs. As an example, we recently announced a design and development partnership with Dukosi to help bring its disruptive semiconductor chip based battery management solution to market.
The many cells in these battery packs need to be carefully and individually charged and monitored since they respond in a bad way to mistreatment like short circuit, over voltage and over temperature while loss of charge is another key monitoring parameter. And this monitoring and management needs to be over the lifetime of the battery pack and not just the lifetime of the car. The re-use of the battery cells and packs for Energy Storage Systems (ESS), which provide grid energy stabilisation, requires a record of the health and performance of every cell.
Our collaboration with Dukosi provides a battery management solution that includes intelligent sensing devices that wirelessly communicate the power pack’s status on a cell by cell basis providing the car and its driver with all the information needed for a stress-free motoring experience and the health and performance data for the second usage requirements.
For more about our full custom ASICs for Automotive and a broad range of Industrial, and other applications contact Sharon Moore at Swindon Silicon Systems.