Emre Sami SÜZER  
Operations Director  
Aktif Mühendislik

Nobel Prize in Physics winner, that was introduced in 2010 as miracle matter. The author of the BBC, David Shukman’s definition “composed of single layer carbon atoms, extracted from graphite, with astonishing properties: the stuff is stronger than diamond, more conductive than copper and more flexible than rubber”. [1]

Thanks to its single atomic size and excellent conductivity, it has become inevitable to use it in energy storage applications of any size – from network-based energy storage to personal size power banks.

I. INTRODUCTION

Thanks to its incredible properties, graphene attracted the attention of many institutions and found numerous uses in a very short time. Considering that studies on graphene began in 2004, the fact that there are 8,416 patent applications [2] in February 2013 reveals the size of interest.

II. DEFINITION

Today, energy storage is mainly made with Lead-Acid, Nickel-Cadmium and Lithium Ion batteries. In the coming years, graphene based storage solutions will gain weight as both the battery and ultra capacitor.

Graphene consists of a two-dimensional form of carbon crystal, a single layer of carbon atom forming a honeycomb (hexagonal) lattice, or several bonded layers of this honeycomb structure. When the graphene word is used without specifying the form (eg, bilayer graphene, multilayer graphene), it usually means single layer graphene. Graphene is the main form of all graphite structures of carbon graphite: graphite is a three-dimensional crystal composed of relatively weakly bound graphene layers. [3]

III. ENERGY STORAGE NEEDS

Energy is an invaluable source of wars over the last century. Today, one of the most important criteria determining the level of development of countries is the amount of electricity used per household.

Unfortunately, energy consumption needs are not as big as production. One of the ways to meet the constant demand is energy storage solutions.

Another area of use of energy storage systems is the need to store regenerative energy in braking operations for reuse. These needs of electric vehicles, has increased its importance, especially with the widespread use of trains.

IV. EXISTING ENERGY STORAGE SOLUTIONS

Although there are many alternative methods of energy storage such as battery, fuel cell, flywheel storage, compressed air storage, magnetic storage, batteries are mainly used one.

Thanks to the high-power density advantage, ultra-capacitor usage has been introduced in the sector in recent years.

V. COMPARISON OF ULTRA CAPACITORS AND BATTERIES

The current ultra-capacitors (supercapacitor) have a major disadvantage in terms of energy density, despite the very high power density.

As can be seen in Figure 5, when the same size battery and super capacitor are compared, the super capacitors can instantly supply the required power, but for a much shorter time.

VI. GRAPHENE BASED ENERGY STORAGE

Graphene technology will help at this point and will be able to charge and discharge at the same, even smaller dimensions, while providing the same energy.

Capacitors need a surface area to increase capacity. Graphene is a very light material and because it has a single atomic thickness, the surface area that can be formed by wrapping in unit volume is very high.

In addition to the existing advantages of ultracapacitors, the following advantages of Graphene will provide the following advantages in energy storage:

• Very long-lasting storage solutions such as 20 years
• Up to 1,000 to 10,000 charge / discharge cycles over existing batteries
• Maintenance-free structure
• Charge in electric vehicles in minutes
• Large-scale storage of regenerative energy in heavy electric vehicles such as rail systems and buses

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