Altech Batteries Ltd (ASX:ATC), in collaboration with the German battery institute Fraunhofer IKTS, is making steady progress towards the commercialisation of sodium alumina solid-state (SAS) batteries.
Their joint venture aims to construct a 100 MWh project in Saxony, Germany, to produce SAS batteries under the brand name CERENERGY.
Altech will hold a 75% stake in the joint venture company, Altech Batteries GmbH, making it the majority owner.
The CERENERGY technology has been developed by Fraunhofer IKTS over the last eight years, specifically focussed on the grid (stationary) energy storage market which is expected to grow rapidly in the coming decades.
Fraunhofer has already invested about EUR 35 million in developing the technology and has established an operating pilot plant in Hermsdorf, Germany.
Altech recently highlighted several advantages of CERENERGY batteries that address some of the issues currently facing lithium-ion batteries.
Fire and explosion proof
CERENERGY batteries are fire and explosion-proof and are not prone to thermal runaway which is one of the biggest advantages over lithium-ion batteries.
Firstly, CERENERGY batteries do not contain flammable liquid electrolytes or plastic separators; the electrolyte is a solid inflammable ceramic tube that allows sodium ions to transfer through it.
Secondly, the battery, due to its chemistry does not contain oxides nor generate oxygen at the cathode like a lithium-ion battery does during thermal runaway.
Being a much safer battery, it is ideal for indoor industrial and commercial energy storage installations.
Large operating temperature range
CERENERGY batteries can operate efficiently between minus 40°C to +60 °C range and guarantee high performances and durability regardless of the ambient temperature.
Because the CERENERGY battery has no liquid electrolyte (solid ceramic electrolyte), ambient temperature does not adversely affect the performance of the battery.
In addition, the CERENERGY batteries are internally high-temperature batteries (270°C) but are fully insulated so the external of the battery module is at “human touch” temperature.
The core temperature of the battery is self-sustaining and does not require cooling like lithium-ion batteries.
They are ideal grid energy storage batteries for extreme cold and desert climates which is a notable limitation of lithium-ion batteries.
Battery life span
Unlike lithium-ion batteries, there is no sodium ion degradation with each charge and discharge.
There is no first cycle loss, no detrimental side reactions, no dendrite growth, or breakdown of anode and cathode structures.
In a recent study by ITP Renewables, the CERENERGY-type battery did not show any deterioration in estimated state of health in the first 700 cycles of testing compared with the normal deterioration in LFP and NMC lithium-ion batteries.
Life span testing of various batteries including CERENERGY-type batteries.
CERENERGY type batteries have been reported with lifetimes of over 2,000 cycles and more than 15 years have been demonstrated with full-sized batteries.
Lithium-free battery
CERENERGY batteries do not contain lithium but use sodium ions from common table salt.
In fact, the cathode consists of salt (sodium chloride) and nickel.
Salt is not a critical element, is many times cheaper than lithium and is readily available everywhere.
This makes CERENERGY batteries immune to the rising prices and potential supply constraints of lithium worldwide.
