Solid-state batteries vs. fuel cells: which will dominate the next decade of new energy vehicles?

A news report claiming "1 minute of charging for 800 kilometers of range" has drawn our attention to solid-state batteries. It seems that solid state batteries have suddenly become the magic bullet for a leap forward in electric vehicles. While a closer look reveals many debatable points in this report from Fisker, it at least demonstrates that solid-state batteries are becoming a new direction in battery development.

On the other hand, fuel cell vehicles, which have been discussed for many years, have recently become a focus of attention as Japanese and South Korean automakers have successively put them into production. Solid-state batteries and fuel cells—which will ultimately be the future of new energy vehicles? And what difficulties will each encounter?

A patent from Fisker, the American electric vehicle manufacturer, claims a "flexible, high-energy-density solid state battery" that could increase the range of electric vehicles   to 804 kilometers and reduce charging time to one minute. This patent, in fact, describes a solid-state battery.

Let's do a simple calculation using basic junior high school physics. Based on the current relatively high energy consumption of 10kWh/100km for electric vehicles, 804km would require 80.4kWh of energy. Therefore, to fully charge that much electricity in one minute, the charging power would need to reach nearly 5000kW.

What does 5000kW mean? It's almost the power output of a medium-sized power plant. Therefore, Fisker's patent only provides laboratory data for a single solid-state battery cell. In reality, considering battery pack integration and grid capacity, the claim of "1 minute of charging for 800 kilometers of range" is merely a marketing gimmick.

However, solid state batteries are indeed a crucial direction for achieving breakthroughs in energy density for automotive power batteries.state batteries are indeed a crucial direction for achieving breakthroughs in energy density for automotive power batteries. Meanwhile, fuel cell vehicles, another area of development, have also been progressing rapidly in recent years. As evidenced by the mutual mockery between Tesla and Toyota regarding each other's technological approaches, it suggests there's more to the story.

                                                   ▎Solid-state batteries: a breakthrough for the large-scale commercialization of pure electric vehicles

Every significant improvement in battery performance is essentially a major revolution in battery material systems. This is because each type of battery material system has its upper limit on energy density.

From the first generation of nickelmetal hydride and lithium manganese oxide batteries, to the second generation of lithium iron phosphate batteries, and now to the widely adopted third generation of ternary lithium batteries, which are expected to remain so until around 2020, energy density and cost have shown a clear trend of increasing and decreasing respectively. Therefore, the choice of battery system for the next generation of power batteries is crucial to achieving the battery goals for around 2025.

Currently, the energy density of lithium iron phosphate batteries is approximately 120-140Wh/kg,while the energy density of ternary lithium batteries produced on a large scale   can reach 130-220Wh/kg, and ternary lithium batteries in the laboratory can reach 300Wh/kg.