Highlights from AABC: Battery Intelligence and simulation, OEM sustainability, the emergence of 48V micro-hybrids, and the pursuit of high energy density cathodes

Voltaiq exhibited at the Advanced Automotive Battery Conference (AABC) in San Francisco in late June. We had fascinating and insightful conversations with industry experts and key players in the automotive, Li-ion, and lead-acid value chains, as well as emerging applications like drones and small aircrafts. Those conversations as well as the excellent group of speakers offered perspectives on the rapidly growing market dynamics. Voltaiq noted a number of key trends from the conference:

Battery Intelligence and simulation were prominently featured from key industry leaders and OEMs

Battery Intelligence is on the minds of OEMs, but modeling alone is not sufficient. Honda R&D, SK Innovation, CATL, and Samsung SDI all touched on battery simulation with physics-based modeling. SK Innovation, spoke about an internal study of cell-testing with two company owned electric vehicles in the field, and while the correlation between simulation and real-world performance was excellent, more data is needed to know if this is scalable beyond the sample study shown.

Meanwhile, Fiat-Chrysler and Honda R&D bridged the gap discussing bringing in-field performance internally to inform vehicle service and product development cycles. Both OEMs have a limited supply of data due to the relatively low number of EVs sold, but nonetheless, the approach is laudable and will provide invaluable benefits as EV sales increase. Ford took a less systematic approach, focusing on vehicle teardowns at end of life to determine capacity and long-term performance. 

While OEMs and cell suppliers exhibited varied strategies, Battery Intelligence and simulation are topics that Voltaiq will take a deeper dive into in a future blog. However, the takeaway is clear, if you are not learning from your organization’s entire body of battery data from in-lab testing to in-field performance, you are not properly leveraging your work. To maintain level with the competition, battery performance data from in-lab testing to in-field packs, needs to constantly inform and feedback into new product development processes. 

Vehicle OEMs are taking sustainability seriously down to raw materials

Vehicle OEMs are serious about sustainability from electric vehicles (EVs) to down to the raw material inputs. BMW’s Peter Lamp presented on the German automaker’s electrification strategy as it shifts focus from its initial foray into plug-in vehicles to electrifying across all product lines.

BMW launched the i3 in 2013, and has since boosted the vehicle’s battery capacity, enabling 50% greater range. Similarly, GM spoke about the automaker’s EV offerings and how materials led to an improvement in delivered range for the Chevy Volt. Both acknowledged that going forward for electric vehicles to reach full market potential, they need to be profitable. To date, that has been a struggle as OEMs work through making a car that is attractive enough to be sold in high volumes. 

Peter Lamp stressed to the material developers in attendance that sustainability of the raw materials cannot be an open question for the industry. Echoing Tesla’s approach to raw material supply, BMW confirmed that it too is looking down the supply chain the raw constituent materials to ensure the sustainability of supplied materials as it looks toward electrifying 20-25% its vehicles by 2025. Electric vehicles cannot have lingering questions about their sustainability and increasing focus on reducing the carbon and environmental footprint of constituent materials is key for long term success.

 48V micro-hybrids have arrived on the market, and are an area of significant growth to meet tightening fuel economy standards

48V micro-hybrids are a significant area of growth for Li-ion batteries that is currently being overlooked. A123 Systems’ Jeff Kessen presented on 48V micro-hybrids, which was the only talk of the conference focusing on low-voltage vehicle electrification enabled by Li-ion batteries. In spite of the recent review of U.S. CAFE standards, the market for micro-hybrids is being boosted by rapidly tightening fuel economy standards in Europe and China, the latter of which is increasing at 6% per year. 

While micro-hybrids are by no means the only way to improve fuel economy in mass-market vehicles, other approaches like light weighting, turbocharging, and increasing the number gears in a transmission, have reached the point of diminishing marginal returns. Vehicles are requiring larger and larger electrical loads which can’t all be met by an alternator. Batteries, in turn, have gotten significantly cheaper and more performant over the past few years. Leaving them as a prime candidate to boost fuel economy at a reasonable price, and meet growing convenience features like vehicle connectivity.

A123 has been an early leader in this market, and reportedly booked $1 billion in micro-hybrid battery sales with a single Chinese OEM alone. Jeff said that A123 is already seeing the market shifting. Initial systems had a relatively small 370 Wh, 48V battery which supported the 12V lead-acid starter battery, but as OEMs become more creative with system architectures, higher energy 48V batteries may begin to support low-speed electric operations like autonomous parking.

Li-ion batteries have come down in price, improved low-temperature performance, and depending on the materials used, support C-rates up to 45C, making them an enabling technology in the path towards improved fuel economy for the mass-market. Expect other cell suppliers to take notice as the micro-hybrid market reaches over 5 GWh before 2025.

High-nickel content cathodes are now being sold in significant volumes, as NMC811 moves out of R&D 

High-nickel content cathodes are no longer next-generation, but there remains work to be done. With materials accounting for around 70% of Li-ion cell costs, the focus on cheaper, higher energy density materials has been a consistent pursuit in the battery industry. Cathodes account for the largest percentage of materials cost in a cell, and are the primary limiting factor to enabling higher energy densities. As such, the industry has long identified increasing nickel content in both NMC (nickel, manganese, and cobalt) and NCA (nickel, cobalt, and aluminum) cathodes as a clear pathway towards more performant batteries. However, material stability, and in turn, cycle life has been a significant challenge, limiting their effectiveness for applications like EVs and leaving them mostly to the realm of research and development.

There were a few indications that things are beginning to change, with players like SK Innovation claiming that they had reached over 2,000 cycles with NMC 811 (a ratio of 8:1:1 of nickel, manganese, and cobalt) at 1C/1C charge/discharge. While those claims are truly impressive and require further investigation, there are signs that NMC 811 is beginning to be commercialized. Ni-rich blends of NMC cathodes like NMC 532 have been in use for some time, Marina Yakovleva of FMC, a supplier of lithium chemicals used in cathodes, said that higher content nickel blends of NMC, like 811, accounted for 1,400 metric tons (MT) while NMC 622 accounted for 6,000 MT in 2016, collectively representing 12% of all NMC supply.

In addition to delivering superior capacity and energy density for Li-ion cells, increasing the nickel content of cathodes decreases the relative share of cobalt, the most expensive material. In other words, not only does the cell become more energy dense, but the material cost actually goes down! On that note, BASF’s Pascal Hartmann, presented on an alternative to higher-nickel content blends of NMC, in NMC 271, that is a high-manganese content blend of NMC. The advantage of NMC 271 would be that it reduces the $/kg materials cost by maximizing manganese, the cheapest material, and in turn, minimizing more expensive cobalt and nickel.

 Across the board at AABC, there was a very strong sense at that electrified transit is poised for long-term consistent growth. While much of the research presented hit on topics of incremental improvements that haven’t drastically changed over the years, the focus on battery simulation and safety testing underscore the importance of Battery Intelligence across the battery value chain.