Hailed as a revolution in power storage, lithium-ion batteries are a $70 billion industry, expected to grow to up to $400 billion by 2032. However, the downsides of lithium-ion are starting to emerge, paving the way for supercapacitor batteries as a better and greener option for power storage.

This is according to Hector King, power division product manager at Dartcom.

King notes that battery technologies have evolved rapidly in recent years: “After around 160 years of lead acid batteries and very little advancement, lithium-ion emerged and evolved very quickly. It rapidly became the most popular option because it covered most bases and became the cheapest option. Now, we’re moving to solid state lithium-ion and supercapacitor technologies, with some stakeholders expecting the lithium-ion batteries widely in use today to be gradually phased out in a few years.”

Modern battery pros and cons

There are pros and cons to every battery technology available, he says. These largely relate to cost and longevity, with environmental impact an afterthought for many organisations. However, the green agenda will inevitably influence battery choices more in years to come.

King explains that cycling capability is a key consideration in batteries. “Lead acid cycles at around 700 – or two years. With the alloys, you got lead carbon offering up to 2800 cycles. When lithium-ion came out, you got batteries that can cycle up to 6,000+ or up to 10 to 20 years, depending on depth of discharge and whether you look after them properly. Solid state lithium can give you up to 18,000 cycles, and supercapacitors in theory could offer around 100,000 cycles for a life expectancy of 45 years.”

Cost influences most battery buying decisions, he notes. Because the price of lithium-ion batteries has dropped in recent years, this technology is currently the most affordable. “At the moment, you might buy a 5kW lithium-ion battery for anywhere between R14,000 and R25,000, whereas the newer technologies cost significantly more. A solid state lithium-ion battery might cost around R70,000 and a supercapacitor battery around R95,000.”

While price is the key factor for most buyers, King points out that there are advantages to investing in the newer technology. 

Stakeholders in the telecoms industry are showing significant interest in supercapacitors for several reasons, one being that their weight and advanced features could discourage criminals. When these batteries are moved from their location, the battery management system shuts down completely. The batteries weigh around 90kg, making them far more challenging to remove and carry away. Additionally, unlike other batteries that can be broken down and recycled into new batteries, supercapacitors have no scrap value. All of these features could act as a deterrent for battery thieves,” he says.

Greener technology

A factor set to become increasingly important for organisations is environmental impact. Lithium-ion batteries contain cobalt, nickel, and manganese, which can contaminate water supplies and ecosystems if they leach out of landfills.

King says: “Unlike lead acid batteries, which are 98% recyclable, lithium-ion battery disposal is becoming a serious problem. At the moment, we send these batteries to a reclamation facility in South Africa where they are disassembled – the iron box goes to scrap dealers, the electronics to an electronics disposal facility, and the ‘black mass’ is sent to specialised facilities in Europe. This is expensive. Building a specialised disposal facility in South Africa would require a multimillion-dollar investment.”

“Lithium-ion’s impact on the environment extends to mining, since the minerals required to build them are only found in certain areas. Supercapacitor technology on the other hand is far more environmentally friendly because it is made mainly of carbon.”

A supercapacitor future

Says King: “I see a big future for the supercapacitor, but it’s still a very new technology, and therefore more expensive. While early supercapacitor technology raised concerns, but as with any emerging technology, these have been addressed. One advantage is you can repair a supercapacitor battery in the field – because a capacitor is a plug in, plug out component, you can just plug a new one in.”

“For any organisation pushing for net zero, the supercapacitor will be the way to go,” he says. “Like most advances, it will start with major companies and trickle down to the rest of us. Organisations should be watching developments in the market and give supercapacitors serious consideration.”