Extending battery life in transportation and mobile applications with supercapacitors

January 03, 2014 // By Jason P Lee, Global Product Manager, Eaton Bussmann
With battery life rising in prominence as one of the most critical areas of system performance and reliability, the introduction of supercapacitors is helping to extend life of batteries in two major application areas. First, they can dramatically reduce battery replacement costs in vehicles such as trucks, cars, ships and motor generators. Second, they can extend the run time as much as 400% in mobile devices such as smartphones and tablets.

Supercapacitors, or supercaps, with their unlimited recharging capability and high energy density, provide automotive, heavy transportation, marine and traction applications with guaranteed engine starting over broad temperature range even when a battery fails.

In mobile electronic systems, supercaps provide the ability to regulate peak current over several different application usage scenarios. With better regulation of the discharge, the batteries are able to hold their peak capacity of energy longer and extend the run time of devices.

Examining the market needs of both application areas demonstrates that the benefits of adding super capacitors but in critically different ways.

Engine Starting

The most critical factor in the transportation sector is engine starting reliability. Every time a lead-acid battery is used to start an engine, it is one step closer to end-of-life. Using a bank of supercapacitors for ignition system relieves the battery from the harsh discharging of engine starts that typically diminish life span. A typical lead-acid battery can have its useful life extend by as much as 70% in certain applications through the use of supercaps. Additionally, starting an engine with a supercap enables greater reliability in colder temperatures.

In the case of the trucking industry, there are several factors where super capacitor usage could help improve daily operations. Typically, 18-wheel tractor trailer rigs and passenger buses carry three to four batteries. When one battery fails, and the vehicle requires a jump start, it can be relatively expensive at a cost of $600 per incident.

Additionally, battery replacement costs are about $200 each and because of this, market research shows that battery theft in both trucks and buses is a problem area. Furthermore, starting reliability for lead-acid cells drops precipitously in temperatures below -23°C. Supercaps, on the other hand can extend that range to -40°C, further improving engine start reliability where cold weather conditions prevail.

In the case of motor generators that are generally used at construction sites where grid power