Supercapbatteries, thermoelectrics to power future cars

February 02, 2015 // By R. Colin Johnson
A new type of electric power storage unit that combines the best of supercapacitors and lithium ion batteries, combined with thermoelectric charging from heat of engines, could be the ideal power source for future vehicles -- from cars to industrial trucks to military convoys, according to Peter Harrop, chairman of IDTechEx Ltd. in Cambridge, United Kingdom.

"Supercabatteries have battery and supercapacitor properties, usually intermediate between the two. While there are lead-acid- and nickel-battery-based versions, the main attention is on ones with a lithium-ion battery electrode and a supercapacitor electrode," Harrop told EE Times .

"These asymmetric electrochemical double layer capacitors (EDLC) are otherwise known as lithium-ion capacitors. They are a promising option for replacing lithium-ion batteries and supercapacitors in automotive applications because they have faster charge and discharge and some other superior properties."

A supercabattery combines one electrode of a batteries with the other from a supercapacitor, also called 'hybrid capacitors' the double layer is the best of both worlds.<br />
(Source: IDTechEx)
A supercabattery combines one electrode of a battery with the other from a supercapacitor, also called 'hybrid capacitors' the double layer is the best of both worlds. Source: IDTechEx)

Superabatteries are gaining traction at future-looking automobile makers world wide, according to Harrop, including BMW, Ford, Komatsu and AIST-The Japanese Government Research Center.

Thermoelectrics, which recover energy that would otherwise be lost to heat generation, will also become commonplace in the cars, trucks and convoys of the future, according to Harrop, as well as in many other applications.

Thermoelectric materials can recover heat energy from the exhaust and motors to recharge the supercabatteries.<br />
(Source: IDTechEx)
Thermoelectric materials can recover heat energy from the exhaust and motors to recharge the supercabatteries. (Source: IDTechEx)

"Thermoelectric devices will be a separate market over 1 billion dollars in 2025 including automotive," Harrop told us.

Until now there have been very few themoelectric sucess successs stories except for novelty items. EnOcean Alliance, for instance, uses thermoelectric devices attached to radiators to generate tiny UHF pulses to operate wireless building controls and Schneider Electric uses them to power wireless sensors that trigger responses to heat overloads on copper busbars.

But so far thermoelectrics have been a failure in cars -- for instance, after 20 years of research BMW was only able to achieve about one tenth of the theoretical maximum -- about 3 percent, according to Harrop. But in 2014 the Japanese maker of giant construction vehicles, Komatsu KELK, was able to prove that 1.5KW could be recovered with thermoelectric innovations that doubled their efficiency to 7.5