Graphene is a composition of carbon atoms tightly bound in a hexagonal or honeycomb-like structure. What makes graphene so unique is that this structure is just one atomic layer thick, essentially making a graphene sheet two-dimensional. This 2D structure produces very interesting properties, including excellent electrical and thermal conductivity, high flexibility, high strength, and low weight. What we’re particularly interested in is the electrical and heat conductivity, which is actually superior to copper — one of the more commonly used conductive metals.

When it comes to batteries, graphene’s capabilities can be used in a number of ways. The ideal use of graphene as a battery is as a “supercapacitor.” Supercapacitors store current just like a traditional battery but can charge and discharge incredibly quickly.

The unsolved trick with graphene is how to economically mass manufacture the super-thin sheets for use in batteries and other technologies. Production costs are prohibitively high at the moment, but research is helping to make graphene batteries are reality.

Graphene vs lithium-ion

Just like lithium-ion (Li-ion) batteries, graphene cells use two conductive plates coated in a porous material and immersed in an electrolyte solution. But while their internal make-up is quite similar, the two batteries offer different characteristics.

Graphene offers higher electrical conductivity than lithium-ion batteries. This allows for faster-charging cells that are able to deliver very high currents as well. This is particularly useful for high-capacity car batteries, for example, or fast device-to-device charging. High heat conductance also means that batteries run cooler, prolonging their lifespan even in cramped cases like a smartphone.

Graphene batteries are also lighter and slimmer than today’s lithium-ion cells. This means smaller, thinner devices or larger capacities without requiring extra room. Not only that, but graphene allows for much higher capacities. Lithium-ion stores up to 180Wh of energy per kilogram while graphene can store up to 1,000Wh per kilogram.

Finally, graphene is safer. While lithium-ion batteries have a very good safety record, there have been a few major incidents involving faulty products. Overheating, overcharging, and puncturing can cause runaway chemical imbalances in li-ion batteries that result in fire. Graphene is much more stable, flexible, and stronger, and is more resilient to such issues.

You don’t have to have one or the other though. Li-ion batteries can use graphene to enhance cathode conductor performance. These are known as graphene-metal oxide hybrids or graphene-composite batteries. Hybrid batteries result in lower weight, faster charge times, greater storage capacity, and a longer lifespan than today’s batteries.

What graphene batteries mean for smartphones

Future smartphones packing graphene power cells would exhibit the benefits outlined above. Handsets, battery packs, and the like could charge as fast or even faster than the current quick-charge technologies on the market. Battery life should also easily last a day or two, if not longer, and devices could be thinner and lighter than they are now.

The move to graphene could offer 60% or more capacity compared to the same-sized lithium-ion battery. Combined with better heat dissipation, cooler batteries will extend device lifespans too. You won’t need to pay for expensive battery replacements after a couple of years to keep your old devices performing in top condition.

Graphene batteries would allow smartphones to be thinner or offer more battery capacity while keeping their current proportions. There are also interesting implications for fast device-to-device charging. With batteries able to support very high currents and blazing fast recharge and discharge times, gadgets could charge each other up at super-fast speeds.

Although portable graphene-battery technology remains some way off, it’s a tantalizing prospect for future smartphones, gadgets, electric vehicles, and much more. Fortunately, hybrid graphene products are already here and should become even more commonplace and affordable in the coming months and years. Graphene is definitely a technology to keep an eye on.