Independent researchers have investigated a sodium battery product they say is as good as established lithium-ion batteries. We don’t promote individual companies. However, when sodium-ion battery performance surprises scientists from Aachen University in Germany, then we deem this worth reporting.
Dismantling the Sodium-ion Batteries
The jelly-roll-type cell battery retained high capacity at extreme charge rates and low temperatures. When the researchers dismantled it, they found a unique NaCu1/9Ni2/9Fe1/3Mn1/3O2 cathode, containing sodium, copper, nickel, iron, manganese, and oxygen in varying proportions.
The team assessed the sodium-ion battery’s performance relative to its lithium-ion competition, after a number of electro-chemical tests. The results persuaded them that it met Tesla standards. And could be a lower-cost solution for large energy storage, and electric vehicles.
However, they noted two issues that they believed required improving. These were low-temperature performance and energy storage capacity. None the less, sodium was an attractive option on account of its abundance and lower cost than lithium.
The German team were less concerned about lower electric vehicle driving ranges, when compared to lithium.They considered that greater affordability outweighed brute power. This is once again a sign of two streams of ion batteries emerging.
Further Surprises the Scientists Found
The Aachen team used non-destructive impedance spectroscopy to examine 120 sample battery cells. This method measured how sodium-ion battery performance responded to tiny alternating electrical signals, at varying frequencies.
This information helped them analyze internal resistance, ion flow, and ageing without damaging the product. Then they used x-rays to scan the batteries internally, before they proceeded to break them down.
The researchers were intrigued to find a tab-less double-aluminum current collector. This lowered internal resistance, and had the effect of reducing internal battery temperature too, imitating Tesla’s own design.
More Information
Will Sodium End Lithium’s Reign?
Sodium-Ion Battery Achieves 500 Cycles
Preview Image: Subject Sodium-Ion Cell