Novi, Michigan-based battery startup Our Next Energy (ONE) started off this week on a major down note by laying off about one-quarter of its staff. The layoffs came as the company seeks to preserve cash as it gets ready to start ramping up production of its in-house lithium iron phosphate (LFP) cells in 2024. However, while layoffs are never great, especially at the beginning of the holiday season, also got some positive news this week with test results from a BMW iX equipped with a prototype of its new Gemini dual chemistry battery that went 608 miles on a charge.
BMW i Ventures was the lead investor in ONE’s series A funding round and last year BMW awarded a development contract to ONE to evaluate the Gemini battery. ONE is taking a different approach to EV batteries from many of its competitors. At the core of its technology is the use of LFP chemistry. Most EV batteries today outside of China use a mixture of nickel, cobalt oxide and manganese or aluminum for the cathode. These nickel rich chemistries generally give the best combination of energy density with a reasonable charge cycle life. However, nickel chemistries are also less stable and can experience thermal runaway when damaged or defective.
LFP cells use none of those materials, instead relying on iron and phosphate (PO4) for the cathode. The downside of LFP is that it has about 30% lower energy density than nickel-rich chemistries, but it’s also stable and resistant to thermal runaway. As a result, ONE uses a cell-to-pack architecture that dispenses with the box in a box set up of typical modular packs used today. This allows nearly double the cells to be installed in the same size pack, with a larger overall capacity and range but at a lower cost than nickel-rich batteries. LFP also the advantage of a much longer charge cycle life, typically lasting as much as 4,000 cycles with minimal degradation in capacity.
The next stage in ONE’s development process is its hybrid, dual chemistry battery that it has dubbed Gemini. The concept behind the Gemini battery is that 99% of daily driving is less than 150 miles. So about half of the pack is filled with enough LFP cells to provide that range for daily driving. The rest is filled with higher energy density cells that are used to replenish the charge on LFP cells when they get depleted.
The production intent version of the Gemini pack will use cobalt-free and anode-free manganese cells. These typically only have a life of a few hundred charge cycles, but given real-world use cases, they are expected to last at least as long as the rest of the vehicle. The manganese cells also have the advantage of being much lower cost than nickel-rich cells and like iron and phosphorus, manganese is readily available in most areas of the world.
Since these manganese cells are still under development, ONE used existing NMC cells for this test program with BMW. The Gemini pack also includes a proprietary battery management system and DC-DC converter to enable the NMC cells to replenish the LFP cells as they get depleted. With the manganese cells, since they won’t be used most of the time, they won’t be subject to the typical number of charge cycles.
With the prototype Gemini battery pack installed in the BMW iX, it went through a process of calibration and then it was put on a dynamometer to run the WLTP test cycle that is now used for certification of new vehicles in Europe. The current production variants of the iX have WLTP ranges between 257 and 380 miles depending on the battery size, motors and wheels installed. The iX with the ONE Gemini battery achieved 608 miles on a full charge. Since the WLTP cycle generally yields about 20% higher range than the EPA testing process, the real-world range of the Gemini equipped iX is probably going to be around 500 miles per charge.
Now that this BMW demonstration has been completed, ONE is focusing on ramping up production of its LFP cells in 2024, eventually reaching a capacity of 20 GWh from its new Van Buren, Michigan factory. ONE is also aiming to complete development of its low-cost manganese cells with a goal of production readiness for the Gemini pack by around 2026.