The nickel-hydrogen battery exhibits an energy density of ∼140 Wh kg −1 in aqueous electrolyte and excellent rechargeability without capacity decay over 1,500 cycles. The estimated cost of the nickel-hydrogen battery reaches as low as ∼$83 per kilowatt-hour, demonstrating attractive potential for practical large-scale energy storage.
The attractive characteristics of the conventional nickel-hydrogen battery inspire us to explore advanced nickel-hydrogen battery with low cost to achieve the United States Department of Energy (DOE) target of $100 kWh −1 for grid storage ( 14 ), which is highly desirable yet very challenging.
Nickel-hydrogen batteries, he says, can last for 30,000 charge cycles, are fireproof, and outperform lithium-ion batteries on a number of key metrics for energy storage at the large scale. Heinemann is CEO of EnerVenue, a nickel-hydrogen battery manufacturer based in Fremont, Calif.
Nickel-hydrogen batteries look and work unlike any other battery. They consist of a stack of electrodes inside a pressurized gas tank. The cathode is nickel hydroxide and the anode is hydrogen. When the battery is charging, a catalytic reaction generates hydrogen gas. During discharge, the hydrogen oxidizes and converts back to water.
The list of innovative approaches is growing. EnerVenue, one more startup, is commercialising a nickel-hydrogen battery. The firm has raised over $400m and will build a plant in Kentucky that it hopes will crank out cheap batteries that can store power for long periods.
In recent years, with the extensive exploration of inexpensive hydrogen evolution/oxidation reaction catalysts, advanced Ni–H 2 batteries have been revived as promising battery chemistry for grid-scale energy storage applications.