So, what percentage of an electric car’s cost is for the battery alone? According to BMW, 40 per cent of the cost of the i4 is for just that. This helps to explain why EVs tend to be so much more expensive than hybrids or plug-in hybrids. Moving forward, BMW plans to put the brakes on this cost when it introduces its sixth-generation battery in 2025 — it, says BMW, represents a 50 per cent reduction in cost at the cell level when compared to the fifth-generation battery.
New BMW battery cells
The new bottom-vented round cells have an energy density increase of 20 per cent and the driving range is 30 per cent better than the outgoing battery. It also has a 30 per cent shorter charging time when juicing the battery from 10-to-80 per cent thanks to the use of a new 800-volt architecture. The combined effects represent a win-win-win situation.
The sixth-generation battery comes in two sizes. Both are 46-millimetres in diameter, but differ in height. The 120-mm tall cells are for use is SUVs; the 95-mm tall cells work for sedans. One of the biggest changes is how the individual cells are loaded into the housing that forms the battery pack. In the past, the large oblong prismatic cells were loaded into modules and then the modules were loaded into the pack.
BMW i7
The new setup sees the individual round cells mounted directly into the pack, which brings a 30 per cent improvement packaging efficiency. The bigger plus, however, is doing away with the module setup reduces the material, weight and cost associated with that system. Affordability aside, it also helps to explain why the new battery produces 60 per cent less CO2 in the process of going from raw material to finished item.
Another of the benefits is the individual cells deliver a better “propagation stop” than the old units. In essence, if one of the cells goes rogue and into a thermal runaway situation where the heat build-up reaches a critical level, it is less likely to affect the surrounding cells.
Read more: BMW to invest US$1.7b for US battery, EV production
Looking further forward, BMW will begin to roll out its all-solid state battery in 2030. The company says this move will increase the energy density by another 20 per cent. The plan is to have a demonstration vehicle using this technology on the road before 2025.
This sixth-gen battery technology will debut in the Neue Klasse (New Class) platform. Currently most of BMW’s electrified vehicles ride on a platform capable of supporting gas/diesel powertrains, hybrids and full-on EVs. The Neue Klasse, which will be rolled out in 2025, is a dedicated EV platform. A successful roll out of the new battery, platform and upgraded electronics along with the fifth-gen electric motors is key if BMW is to attain its goals.
As early as 2023, BMW will offer at least one fully-electric model in most of the segments it competes in and plan to have more than two million fully-electric vehicles on the roads by 2025. Come 2030, the company wants half of its global sales to be fully electric. In North America, this ambitious push will be helped by a US$1-billion investment in BMW’s assembly plant in South Carolina. In the future, the Spartanburg facility will build at least six fully-electric vehicles by 2030.
BMW bets on hydrogen fuel cells
Unlike its Stuttgart neighbour, Mercedes-Benz, BMW says the hydrogen fuel cell is still very much part of its future powertrain lineup — the company has announced an electric drivetrain based on its fuel cell is doable in the Neue Klasse platform. For now, a small number of iX5 Hydrogen vehicles are going into production and will be used for demonstration and testing purposes starting in 2023. BMW did not say how many iX5 Hydrogens will be built, but during the fuel cell assembly area tour I spotted fuel cell number 67. It was neatly crated and ready to go to vehicle assembly, so around 100 units sounds like a good number.
BMW fuel cell system
While the iX5 Hydrogen shares its inner cells with the Toyota Mirai, all of the ancillary hardware is from BMW. In this case, the fuel cell works with a 2.5-kilowatt/hour battery that acts a buffer as the fuel cell ramps up to speed and it helps improve initial acceleration.
The iX5 gets its hydrogen from two tanks mounted in a “T” shape. They sit in the central tunnel and under the rear seat area and carry six-kilograms of hydrogen pressurized to 700-bar. When asked about the risks associated with hydrogen in the event of a major crunch, BMW says it is safe. First, the carbon-fibre composite tanks each have a shut-off valve that automatically seals off the hydrogen. More importantly, of the six-kilograms of hydrogen stored onboard only nine-grams is outside of the tanks — in the pipe leading to the fuel cell stack and the stack itself. Asked to described what happens when nine grams of hydrogen ignites, the engineer leading the tour described it as little more than a spurt.
BMW iX5 Hydrogen
Moving forward, the whole hydrogen storage system is going to be completely revamped. The plan is to design a tank system that will be the same size as the sixth-generation battery pack. This simple switch means future fuel cell vehicles can be built on the same assembly line as their battery-electric counterparts.
Interestingly, BMW seems to be putting its money on the fact the Alternative Fuels Infrastructure Regulation (AFIR) committee agreed on a target of one hydrogen refueling station every 100 km across Europe’s highway network. This would be enough coverage to ease range anxiety. Looking forward, Hydrogen Europe estimates the number of hydrogen refuelling stations will reach 1,500 by 2030. That’s up from the 136 stations today.
