By Paul Homewood

h/t Dave Ward

Others have already investigated the potential cobalt cliff. Now another paper comes to the same conclusions:

Electric vehicles need powerful, light and affordable batteries. The best bet is commercial lithium-ion cells — they are relatively compact and stable. But they are still too bulky and expensive for widespread use.

The performance of rechargeable lithium-ion batteries has improved steadily for two decades. The amount of energy stored in a litre-sized pack has more than tripled, from around 200 watt hours per litre (Wh l^–1) to more than 700 Wh l^–1. Costs have fallen by 30 times, to around US$150 per kilowatt hour (kWh). But that still exceeds the $100 per kWh goal for affordability set by the US Department of Energy. And batteries that are powerful enough for an electric car (50–100 kWh) still weigh around 600 kilograms and take up 500 litres of space.

The pace of advance is slowing as conventional technology approaches fundamental limits. The amount of charge that can be stored in gaps within the crystalline structures of electrode materials is nearing the theoretical maximum. Projected market growth will not lower prices substantially — the markets are already large.

Worse, the materials used in electrodes, notably rare metals such as cobalt and nickel, are scarce and expensive. Surging battery production has almost quadrupled wholesale prices of cobalt over the past two years, from $22 to $81 per kilogram.

High demand and prices are already encouraging some producers to cut corners and violate environmental and safety regulations. For example, in China, dust released from graphite mines has damaged crops and polluted villages and drinking water¹. In Africa, some mine owners exploit child workers and skimp on protective equipment such as respirators. Small artisanal mines, where ores are extracted by hand, often flout laws. Some companies, including BMW, follow strict policies to verify their cobalt suppliers². Many do not.

Alternative types of electrode based on cheap, common metals such as iron and copper need to be developed urgently. In our view, the most promising candidates involve ‘conversion materials’, such as copper or iron fluorides and silicon. These store lithium ions by bonding chemically with them. But the technology is still at an early stage. Problems with stability, charging speed and manufacture must be overcome.

We call on materials scientists, engineers and funding agencies to prioritize the research and development of electrodes based on abundant elements. Otherwise, the roll-out of electric cars will stall within a decade.

Read the full story here.

Human ingenuity has a habit of finding a way past cliffs and peaks, and no doubt some alternative way will be found to avoid this latest pitfall.

But what a crazy world we live in when we so readily toss workable technology away, to embrace something else which patently does not yet work and may quickly become unsustainable anyway.