The Ground Handling Blog

Mototok's blog for Hangar Professionals

Written by Mototok on February 25, 2022 // 12:00 PM

The Pathway to Better Energy Storage


Everyone born in the last four or five decades or sooner has grown up with the ever-present idea of the electrification of vehicles. Moreover, it was always present in science-fiction movies.

Therefore, it should be no surprise that electric cars were a prime first candidate for electrification. However, they are a more complex process to tackle due to the long ranges required of cars.

Electricity has been used widely in the industrial sector for many years, mainly in work environments where carbon emissions were too dangerous to use, namely mining and warehouse work. The thing about these work environments is that it doesn't matter how heavy the batteries are or their range/run-time. For example, a battery storage rack in a warehouse can hold many batteries and swap them out as needed. Cars don't have that luxury, and neither do machines operating in less controlled environments.

We're going to look at different energy storage solutions, what has worked, what is working, and where the industry is headed with electrical power storage solutions.

What Is Energy Storage

What exactly is energy storage? Energy storage is an avenue that stores and retains energy from one source (solar, wind, or electrical energy from an electrical service) to be used either at a later date or in a mobile application where it must be separated from an electrical umbilical.

In this case, we are talking about batteries. A simple name and simple concept, but with a lot of variables.

Current Energy Storage Compositions

Batteries come in an unbelievably diverse array of shapes and sizes. Still, they all have the same purpose: to store energy for later release. Unfortunately, out of the many batteries, only a few are rechargeable, and fewer yet are suitable for operating vehicles. 

Historically, two main types of batteries have been used for electric vehicles: lead-acid and lithium-ion.

Lead-acid Battery

The lead-acid battery is an ancient design and was the first rechargeable battery in the world, dating back to 1859! Lead-acid batteries are not the most efficient energy storage mode, but they are easily paralleled for added storage or tied in a series to amplify voltage. 

Moreover, lead-acid batteries are a cheap option. They provide high surge currents, making them very popular for high-draw applications, notably combustion engine starting. But they are also made in a deep cycle, meaning they can be fully depleted and then recharged often.

Deep-cycle batteries are the preferred energy storage option for solar-power assemblies in residential dwellings: they are very inexpensive (relatively), easy to find, easy to replace, and can be easily tied in a series to match the voltage needs of the house.

Lead-acid batteries are prevalent in heavy industrial warehouse equipment where range is not a huge issue, and heavyweight is a benefit. It is also the preferred power for the early-generation electric aircraft tugs, where weight is also an added benefit; a light tug cannot control the aircraft it is towing. In addition, tying together a dozen batteries in parallel is insignificant for a heavy tug; the battery pack takes the place of the mass created by an internal combustion drivetrain.

Considering how easily acquired lead-acid batteries are and how cheap they are, it doesn't seem likely that they will be going away anytime soon.

Lithium-ion Batteries

Lithium-ion batteries are a much newer technology than lead-acid and are rechargeable batteries made up of cells. These cells have lithium ions moving from the negative electrode to the positive electrode through an electrolyte.

Lithium-ion batteries have a much higher energy density than lead-acid batteries, making them a natural fit for electric cars and motorcycles, where energy-dense batteries are necessary. They are also mainstream in tablets, phones, laptops, and rechargeable flashlights.

The biggest issue with lithium-ion batteries that we are finding out now is that they are much more difficult to recycle than a simple lead-acid battery. Lead-acid batteries are pulverized, and then most of the components (lead and plastic) are completely recyclable for another production cycle. Lithium-ion batteries are not so easily recycled.

This is going to pose a rising problem in the years to come. Why?

There are now well over a million electric cars on the road. All of these rely on lithium-ion battery packs to power the electric motors. But unfortunately, lithium-ion batteries are very reliant on complete charge-discharge cycles.

You must use Lithium-Ion batteries regularly as designed, or their capacity will be diminished. But back to the problem. Eventually, several million lithium-ion packs will reach their life-cycle threshold shortly. What will we do with them? Honestly, nobody knows.

And this problem goes a lot deeper than it might initially appear. What do you do with a car when the life-cycle threshold is reached on the battery pack? Regardless of its powertrain, all cars plummet in value over time. By the time the battery packs are spent, chances are it isn't worth the money to replace the batteries, and even if you wanted to, who would do it? So EV drivers are stuck between a rock and a hard place because they may end up with a worthless car.

What The Future Holds

This is getting into uncharted territory. On the one hand, it is inspiring! Electric cars are exciting; the Tesla S Plaid boasts a 0-60mph time of under two seconds, which you would expect from a car pushing more than one thousand horsepower.

But there are two sides to this coin. First, there is an awful lot of potential waste when cars that are otherwise in serviceable condition may get crushed because there is no value in keeping them on the road once the batteries are toast.

Automobiles are the most visually evident component of the global carbon reduction campaign, mainly because so many cars are in circulation, but the technology does not stop there.

2030 Agenda for Sustainable Development

Regardless of personal preferences, the global roadmap for carbon emission reduction has been laid out and adopted by the United Nations General Assembly in 2015. In this roadmap are seventeen Sustainable Development Goals and many more sub-goals.

This is mainly in concert with the 2050 Low Carbon Roadmap, the ultimate way-ahead for carbon-zero power production. The only way to accomplish this mathematically is to have the bulk of road vehicles be electric vehicles.

But in meeting this deadline to achieve actual carbon-zero status, we must look beyond the road; it will also require support equipment to become sustainably powered.

It is hard to put a number to it. Still, there are many hundreds of thousands of diesel-powered aircraft ground equipment globally. Unfortunately, these, especially legacy equipment, are not good options moving forward.

Sustainably minded GSE will be electric-powered, which is two-fold: first and foremost, it is environmentally responsible. Second, it is a safer and far more practical power source.

Airports are a natural environment for harvesting solar energy; an Australian study indicated that an average-sized international airport had enough area to support a city of approximately 136,000 houesholds. This is more than enough solar energy to maintain all electric GSE and power the remainder of the airport!

Lithium Titanate

This brings us back to our discussion of battery types. Even the most rugged GSE is reliant on the technology of the times. Lithium-ion is the most prevalent battery type for an advanced piece of GSE. Still, it will eventually run into the same fate as cars are facing: the battery packs will reach their cycle threshold.

Lithium titanate is an emerging solution that poses a significant advantage over lithium-ion. It charges far faster than lithium-ion, enabling fifteen-minute charges of batteries in any weather conditions. Regardless of the application, one of the most significant drawbacks to battery-powered vehicles is the impact of weather (particularly cold).

The drawback is low energy density, but this may have to be worked around for the overall significance of an all-weather energy storage solution.


This is an exciting time for the electric vehicle industry; there are mounds of research being conducted to provide the best possible solutions for many applications. While there are some limitations to electrically powered GSE, it is a significant step forward. Of course, diesel power may always have a place in the industry. Still, electrical power is a better option for many applications, namely aircraft towing. For one, they have minimal maintenance demands, meaning they will be on the ramp a lot more than the shop. Second, idling tugs waste a lot of fuel. An electric tug not only uses no energy while it is parked, but it also is cheaper to fill than a diesel tugs many times over.

Whatever the future holds, Mototok is poised to take your business to the next level, regardless of your business. Give us a call, and we can set up a consultation to see which of our tugs is the best fit for you and your operation!

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