StoreDot moves to B sample validation with multiple automakers

January 23, 2024 EV battery 7 min read

Founded in 2012, StoreDot is an Israel-based company developing extremely fast-charging Lithium-ion battery technology. In this interview with CEO Doron Myersdorf, we discuss the progress of StoreDot’s fast-charging, Silicon-anode based Lithium-ion battery technology in 2023 – including the current status of OEM validation, manufacturing regions & partners, and plans to showcase the ‘100-in-5’ technology in a Polestar vehicle early 2024.

Could you provide a brief overview of your XFC (extremely fast charging) Lithium-ion cell chemistry?

Our XFC cell features a design where we replace traditional graphite anodes with silicon nanoparticles. This swap allows much faster charging. However, it’s not just about changing the anode; we also modify the electrolyte, the cathode, and the separator.

Silicon is the sole active material in the anode. However, there are additional elements like organic binders, conductive additives, and proprietary polymers that we incorporate to secure the silicon within the anode’s structure, preventing swelling or expansion of the entire battery. We use NMC 811 for cathode.

It’s a holistic cell design aimed at optimizing extremely fast charging, with charging times as low as a few minutes. The product we have introduced, the ‘100-in-5’, achieves 100 miles or 160 kilometers of range addition in just 5 minutes, and it’s currently undergoing testing with over 15 car manufacturers.

How has OEM validation progressed this year, and have any OEMs transitioned from A sample to B sample testing?

The OEM validation process has been very successful. All OEMs have validated the data sheet of ‘100-in-5’ cells, showcasing energy density of more than 300 Watt-hour per kilogram and approximately 750 Watt-hour per litre – which we have maintained without compromising on the 100-mile charging in 5 minutes. It’s a breakthrough, providing rapid charging without compromising battery life and offering top-tier gravimetric and volumetric energy density.

You recently announced a collaborative project with Polestar, which is set to debut in early 2024. Please tell us more about it.

Polestar is one of our strategic investors, and they have been a part of the testing process. They are positioning themselves as a leader in extremely fast charging and high-performance electric vehicles, so this technology fits very well into their strategy. StoreDot and Polestart are investing resources to build the first vehicle to use our XFC technology.

At Polestar Day in Los Angeles, StoreDot’s XFC pouch cell charging demonstration was shown alongside Polestar’s prototype battery module that integrates XFC technology.

Together, we plan to demonstrate StoreDot’s XFC technology at full scale in a Polestar 5 prototype in 2024.

After supplying the cells, does StoreDot also play a role in battery pack design?

This program with Polestar is a joint program because it is the first time ever that you are deploying this technology into a vehicle. There will be some iterations to optimise the cell size, the wiring, the busbars, the cooling, and the software, and we are heavily involved in all these developments. A joint team is working to ensure that we deliver this vehicle in a safe and cost-effective manner. We need to extend our capabilities into the value chain to ensure that cells perform correctly.

What would be your expected cell price in 2024?

Our target is to be very close to traditional lithium-ion batteries with a graphite anode, which is currently around $120 per kilowatt-hour. Initially, we might be 5-10% more expensive due to the silicon supply chain, but as volume increases and economies of scale come into play, we aim to be comparable. Silicon is pricier, but its potential for tenfold energy makes it efficient, resulting in using less material. So, in a direct comparison, we are only slightly more expensive today, with hopes of reducing that margin in the coming years.

During this year, have you added new manufacturing partners or regions in addition to EVE Energy in China?

We are also producing cells in Korea with a third party.

EVE Energy is still the mass manufacturer in China.

Additionally, we have signed agreements with Itavolt in Italy and Statevolt in California.

We also recently announced a collaboration with Flex|N|Gate in Canada, actively scaling up battery production.

Our goal is to have production agreements wherever vehicles are manufactured.

Besides Polestar, are there other automakers progressing in the validation process?

Yes, but I can only talk about strategic investors because this is public information. Volvo, VinFast, and Daimler have all gone through testing and validated the performance. With some of them, there are B sample programs in motion. In addition, there are other B programs with some companies that I can not yet mention. There are at least 5 of B sample programs.

How long does it typically take to move from B sample testing stage to mass production and deployment?

The challenge is that each OEM is a little different in terms of the form factor. Some of these samples are prismatic, which is new to us. I think it will take 9 to 12 months to qualify the B samples and then move to the C samples.

C Sample means going into the mass production line, which depends on where the cells will be produced. So, we are looking at 2026 as a target for mass production.

What would be StoreDot’s primary focus in 2024?

Our main focus will be developing B samples in prismatic form factor, which is a significant challenge despite the proven chemistry. We must show that we can package the technology into the form factors the OEMs ask for.

Additionally, we are exploring new agreements with manufacturing partners like Vinfast in Vietnam. They are also building a facility in North Carolina in the US.