Supercapacitors: Superheroes for Locomotive Starting Power

Many items on a locomotive endure general wear and tear, and locomotive batteries are no exception. Even well-maintained and replaced batteries can experience troubles starting the locomotive. The regular starting of a locomotive can cause damage to batteries and reduce their lifespan, resulting in frequent replacement and reduced lifespan. But, there is a simple solution:

Supercapacitors to the rescue!

Think of the supercapacitor as a lighter, quicker cousin of the slow, heavy, lead acid battery. Both are powerful sources of energy with their own unique compositions and abilities that complement each other when used together for locomotive starting, and can vastly improve both battery life and locomotive starting reliability. Find out how in this video, and read on for more details!

The Starting Power of ZTR's KickStart

Locomotive Loads

Advanced systems used by locomotives place varied demands on batteries. Starting systems require a quick burst of power, which is hard on a battery. A battery-only solution is expected to provide in excess of 1500 amps during the initial crank. The voltage drop may reset electronics, causing a penalty brake application. Other systems like the safety and communications systems have significantly different requirements that are a constant low-current draw on the batteries. All of these requirements can limit the useful life of a battery, making it weak, which can result in starting difficulties. The best source for the variety of power required by locomotives it to have a combination of lead acid batters and supercapacitors. This combination provides the right jolt of starting power while allowing the batteries to supply the necessary power for other systems.

How do supercapacitors help with locomotive starting?

Supercapacitor systems like the ZTR KickStart™ work with the locomotive’s regular batteries to deliver the power required and reduce damage. Supercapacitor technology supplies the bulk of the power needed during the initial crank. This helps the locomotive batteries during the locomotive engine starting phase by providing a surge of additional electrical current at the beginning of the cranking sequence. This reduces the stress on the batteries. By matching the power source to the load required, the strain on the batteries is reduced and the result is less energy drain from the batteries, longer battery life, faster cranking speed, less time to recharge the batteries and increased locomotive availability. Plus, electronics stay on, and no penalty application occurs.

What are the major differences between batteries and supercapacitors in locomotive applications?

Supercapacitors can be used to help augment the batteries in locomotive starting, or can start the locomotive all on their own. It depends on the need and the customer preference. With this in mind, it's important to know how batteries and supercapacitors differ when considering a supercapacitor battery assist or full-start solution.


  • Slow to recharge, slow to disperse energy
  • Multiple recharges can affect overall life
  • Require maintenance
  • Last approximately 5 years (often with a rebuild)
  • Reduced ability in cold weather
  • Starting and powering locomotive systems



  • Recharge faster than batteries and release a high amount of energy quickly
  • Zero maintenance
  • Last 10-15 years or more
  • Quick burst of energy
  • Withstand extreme weather conditions
  • Locomotive starting only

Let’s take a closer look at some of the differences.

Energy Storage and Release

Understanding how the two systems store and release energy is critical to better understanding their difference. When it comes to locomotive batteries, even the best ones use electrochemically stored energy. Unfortunately, this type of energy storage limits the peak current available. That initial burst of energy required at the beginning of the locomotive starting, the cranking phase, requires a peak of current. On the other side, supercapacitors use electrostatic energy. The benefit of this process is that it can deliver nearly all the energy stored, in the supercapacitor, in a split second. It’s like a bolt of lightning or an instantly-available high power burst. Since a locomotive requires this surge of energy as well as a steady supply of longer-term energy, these two systems together are the perfect combination for a locomotive.

Life Span

All batteries have a "best before" date that depends on usage and environmental conditions. Deeply discharging a battery, neglecting to apply a full charge after depletion, utilization in extreme temperatures and lack of routine maintenance can all have a devastating effect on a battery’s specified (and expected) lifespan. Supercapacitors have a specified lifecycle of more than 500 times that of a battery, and aren’t affected by deep discharges, lack of full charges, or temperature extremes – and they don’t require any maintenance.




(Lead Acid – SLA, AGM, Gel, etc)


Charging Time

> 12 hrs

< 60 seconds

Cycle Life



Calendar Life

3-5 years

10 + years

Operating Temperature

-20°C +55°C

-40°C to 65°C


Whether you would benefit from a battery-assist technology to augment power during engine starting, or from a complete solution that leaves batteries available to properly power onboard systems, supercapacitors are a valuable alternative that can reduce operational costs and increase your fleet reliability.

Find out more or railwayinfo [at] ztr [dot] com (subject: KickStart%20Info%20Request, body: Hello.%20%0AAfter%20reading%20about%20your%20KickStart%20supercapacitor%20solution%2C%20I%20would%20like%20more%20information.%20Please%20contact%20me.%20) (contact us) for more information about the ZTR Kickstart™.

Rail News
Select the filter(s) below to display relevant content.