Electric cars were once expected to be the ultimate travelling option of the 21st Century only to be maligned about the safety of plug-in vehicles compared to regular combustion engine cars. Now with Continental’s new evSAT some of those fears can be allayed.
The tyre manufacturer has developed a sensor for electric and plug-in hybrid vehicles that shuts off the high voltage battery in the event of a collision, which allows emergency service personnel to aid accident victims without the risk of suffering an electric shock.
Continental, which is an international automotive supplier, has developed a sensor (satellite) for electric and plug-in hybrid vehicles which will immediately shut off the high-voltage battery in the event of a collision. This means that emergency service personnel can come to the aid of accident victims without the risk of suffering an electric shock.
“The evSAT acceleration sensor is active in charge mode. It detects an accident and passes this information on to the battery management system which then shuts off the high-voltage battery,” said Dr. Axel Gesell, Senior Manager Platform Development Sensors & Satellites, in the Passive Safety and ADAS business unit of Continental’s Chassis & Safety Division. “The major benefit of our product is that it prevents fire and rescue service personnel sustaining high-voltage injuries when coming into contact with vehicle metal parts or if they have to cut through the vehicle to recover accident victims,” Gesell added.
Electric vehicles and plug-in hybrids are powered by high-voltage batteries of up to 400 volts. evSAT will go into series production with a major German vehicle manufacturer in 2012. ‘evSAT’ stands for ‘Satellite for Electric Vehicles’ and essentially consists of an independent, triaxial sensor with a CAN (controller area network) interface.
During the charge phase, the other vehicle electronics, including the airbag system are not operational. So as to avoid the considerable expense of adapting the airbag system to meet new requirements, Continental has developed evSAT for the vehicle’s charge mode. The accelerator sensor employs an algorithm to detect a frontal, rear or side collision with another vehicle and immediately transmits a signal via the CAN interface to the battery management system which then switches off the battery within half a second. If the electric or plug-in hybrid vehicle has been switched off and is not being charged, the evSAT moves to a standby mode to prevent the battery discharging. As such, evSAT represents an additional passive safety system function for electric and plug-in hybrid vehicles.
Most high-voltage batteries in electric or plug-in hybrid vehicles generate a voltage of 400 volts, twice as great as the standard domestic plug socket and potentially fatal. Already, in the United States, there is a legal requirement for the vehicle power supply voltage to fall to below 60 volts within five seconds of an accident occurring.
“As electro-mobility continues to develop, the safety of electric vehicles will assume an increasingly important role. The need for technologies to meet future challenges is already demonstrated by the additional demand for evSAT from numerous other vehicle manufacturers,” said Telmo Glaser, Continental’s evSAT project manager.
Indeed the evSAT will react in the same way if it detects a rollover in driving mode with the battery deactivated within four seconds. In other types of accidents it remains inactive with the airbag system assuming the task of cutting off the battery.
The device can be installed in a number of places in the vehicle but should be placed sufficiently well inside the vehicle to avoid being damaged during the accident. It is expected to go into series production with a major German carmaker in 2012.
"Combined global sales of hybrid electric vehicles (HEVs) and battery electric vehicles (BEVs) are expected to total 5.2 million units in 2020, or just 7.3 percent of the 70.9 million passenger vehicles forecasted to be sold worldwide by that year," automobile market research company J.D. Power & Associates said in a recent report.
According to a recent report ,plug-in electric vehicles, including plug-in hybrids and battery electric vehicles, have the potential to make up 9 percent of auto sales in 2020 and 22 percent in 2030 (1.6 million and 4 million vehicle sales respectively).