There are already car manufacturers testing these incredible American semi-solid state batteries

In any aspect related to the electric car, it seems that China is ahead. Nio has introduced the first mass-produced semi-solid battery pack, for example. But they are not the only ones advancing in this direction. Massachusetts-based Factorial Energy has been working on its quasi-solid-state lithium technology for more than a decade.

Backed by automakers including Stellantis, Mercedes-Benz and Hyundai, its goal is to create a long-range, high-energy-density battery that costs the same as traditional lithium-ion batteries and comes off the same production lines. It's not a chimera. It has already sent the first batch to Mercedes-Benz for vehicle testing before further development.

Factorial first revealed its 100 Ah solid-state cell at CES 2023 in collaboration with Stellantis. This was a step up from the smaller cells he had previously shown. It began shipping 100 Ah A samples to automotive partners in October last year and has just shipped over 1,000 A samples cells to Mercedes-Benz alone.

Now Factorial has announced the shipment of the first 106 Ah sample B cells to Mercedes. It describes it as the first shipment of solid-state battery cells to a global automotive manufacturer. It does not mean that it is the first, but rather the first “announced”, if we read carefully between the lines of the statement.

There is no doubt that there is constant progress. Every battery cell, like any other component in the automotive industry, goes through several stages of testing and development, from samples A to D, before production. If they are testing B samples, we are no longer talking about prototypes, but rather they are beginning to gain maturity and will be subjected to more severe tests.

These cells will be integrated into modules and battery packs for extensive testing and optimization, Factorial claims in this month's shipment. “This crucial phase involves validating module and package designs against Mercedes-Benz’s strict performance specifications.” This step “will confirm the strength of Factorial's supply chain and its manufacturing processes, guaranteeing scalability for future vehicle tests,” the company indicates.

Factorial cells are based on the Factorial Electrolyte System Technology (FEST) with a lithium-metal anode, a quasi-solid electrolyte and a high-capacity cathode. It reaches (according to the company) an energy density of up to 391 Wh/kg, far exceeding the 300 Wh/kg ceiling of current generation lithium-ion technology and more than double the 160 Wh/kg of the usual LFP (lithium-iron-phosphate) type batteries. Additionally, the quasi-solid electrolyte improves safety compared to liquid lithium-ion electrolytes.

How does this translate into a car? Well, autonomy of more than 600 miles (966km) per charge with a 90 kWh battery, which would also reduce its weight and size by 30% compared to conventional lithium-ion packs. FEST batteries are designed to be produced using the same equipment used to produce lithium-ion batteries, with minimal changes.

The first plant opened in October 2023, in Boston (Massachusetts) and in April of this year they signed a memorandum of understanding with LG Chem to accelerate the development of these solid-state batteries.

Via: Factorial

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