Researchers at Japan’s National Institute of Advanced Industrial Science and Technology (AIST) have succeeded in making the world’s first Ni-Li battery, a formulation that holds more than 3.5 times the energy of Li-ion batteries and doesn’t run the risk of catching fire.
By including a membrane made of the recently developed glass-ceramic film called LISICON between two otherwise incompatible electrode materials, each electrode can be bathed in its own substance-specific liquid electrolyte solution which is at the same time prevented from coming into direct contact with the other. Thanks to the unique properties of LISICON, the separated electrolyte solutions are readily able to pass electrons across the membrane, and so the entire unit still functions as an operational cell.
Reasoning that by combining the best properties of NiMH batteries with those of a Li-ion battery they could obtain an “ultrahigh” energy density, the researchers placed a nickel hydroxide cathode in a liquid electrolyte and the lithium metal anode in an organic electrolyte separated by the LISICON glass, and Eureka! The World's first Li-Ni battery was born!
The new cell has already obtained a “practical energy density” of about 194 watt hours per pound of battery material, or 3.5 times the density of a typical Li-ion battery (at about 55 watt hours of energy per pound of battery).
Using the Tesla Roadster for comparison purposes, the car's current Li-Ion battery which weighs 1000 pounds and contains 53 KWh of energy, can propel the car about 200 miles in normal use. By contrast the same weight of Ni-Li battery would hold 194 KWh of energy for a range of approximately 700 miles!
The implications for electric vehicle design and adoption are obviously tremendous, but several issues need to be overcome to bring this technology to market.
For instance, recharge time for such a battery on standard U.S. household current would be several days. And the cell itself is structurally more complex than current cells, no doubt making it more expensive to manufacture. Additionally, the Lisicon glass barrier is an unknown in terms of long-term durability. A cell design would need to be produced that preserves this membrane for the life of the battery.
Nevertheless, in comparison to the hurdles to commercialization faced by other Super-battery and/or capacitor technologies, these issues seem relatively straight forward; In the race for the elusive EV energy-storage breakthrough, the Ni-Li battery may have suddenly moved to the pole position.