Sodium-ion, solid-state batteries can’t eliminate fire risks: Alsym Energy CEO

US firm aims to develop lithium-free battery with high energy density

By Park Jae-hyuk

An Indian American entrepreneur running a battery startup in Massachusetts claimed that sodium-ion and all-solid-state batteries are not suitable alternatives to lithium-ion batteries in terms of reducing risks of fire and explosion.

Mukesh Chatter, the founder and CEO of Alsym Energy, told The Korea Times in a recent interview that Alsym Green, his company’s lithium-free battery using a water-based electrolyte, will be a better option, once its development is finished.

“Alsym Green’s materials are inherently non-flammable and non-toxic, and made using readily available materials with robust, uncomplicated supply chains,” he said.

“It is the only non-flammable stationary storage option that is truly suitable for urban areas, and is also an attractive option for warmer equatorial regions.”

His remarks came after a deadly lithium battery plant fire here last month raised global concerns about the safety of batteries containing lithium.

Although single-use lithium batteries caused the fire at Aricell’s lithium battery plant in Hwaseong, Gyeonggi Province, fears are lingering among consumers over the safety of rechargeable lithium-ion batteries used for electric vehicles (EVs), mobile phones, laptops and energy storage systems (ESS).

After a local fire department suggested that the factory’s 23 workers died primarily from the inhalation of toxic smoke from the burning materials, rather than direct burn injuries, the toxicity of minerals used in lithium-ion batteries is also drawing attention.

“Lithium-ion batteries provide high energy density in small footprints, but concerns about fires and explosions in stationary storage applications have the potential to slow the clean energy transition,” the Alsym Energy CEO said.

“Toxicity is a concern, with lithium-ion capable of producing deadly hydrogen fluoride and carbon monoxide gases.”

In response to growing worries, global battery firms have tried to develop alternative products.

EcoPro recently developed cathode materials for lithium-free sodium-ion batteries. LG, Samsung and SK are ramping up efforts for the mass production of all-solid-state batteries using solid-state electrolytes that can reduce the risks of fire and explosion.

Chatter, however, pointed out that those batteries cannot eliminate fire risks completely.

“Most sodium-ion batteries that have been announced use the same flammable organic electrolyte solvents that are found in lithium-ion batteries,” he said.

“They may be less prone to fires and explosions resulting from internal short circuits but will have many of the same fire and explosion risks as lithium-ion when heated, abused or damaged.”

The U.S. firm’s chief added that sodium-ion batteries are not suitable for use in stationary storage or mobility applications due to very low energy densities.

Regarding all-solid-state batteries, he pointed out their high costs, which can make them non-viable for large scale applications such as grid storage.

“Researchers at Sandia National Laboratories in the U.S. have also warned that solid-state batteries are still likely to catch fire or explode if crushed or punctured,” he said.

“In contrast, Alsym cells pose no risk of fire or explosion in any situation.”

Alsym Energy seeks to come up with samples for Alsym Green during the first quarter of next year and start production in commercial volume by early 2026, based on investments from venture capital firms including General Catalyst, Thrive Capital and Thomvest, as well as strategic investors such as Tata.

Chatter emphasized that Alsym Green offers higher energy density than other non-flammable batteries.

“We use inherently non-flammable and non-toxic materials, and our electrolyte is water-based,” he said.

“One electrode is primarily manganese oxide, and the second electrode is primarily a different mixed metal oxide. We also use a standard commercially available separator.”

He added that Alsym Green cells are similar to lithium-ion when it comes to construction and form factor and can be manufactured using lithium-ion equipment.

However, it remains uncertain when the company’s battery will start being used for EVs.

“Alsym Green is optimized for stationary storage applications,” Chatter said.

“Future products currently in development will meet the needs of marine and mobility applications.”

Who is Mukesh Chatter?

Chatter was previously CEO and co-founder at Nexabit Networks, a terabit switch/router company, which was acquired by Lucent Technologies. He has a master’s degree in computer and systems engineering from Rensselaer Polytechnic Institute in New York. He was named one of the top 10 entrepreneurs of the year by Red Herring Magazine in 1999. He has 23 patents granted, and more currently in review.