Honda’s 6,000-ton mega-casting machine is able to stamp out battery cases in two separate pieces. This flexible-cell approach can produce cases for EVs of different sizes and reduce the number of parts required to build the case from 60 to just five.Courtesy of manufacturer
Small improvements can lead to big results. Honda is betting on this with its upcoming 0 Series – pronounced Zero – line of battery-electric vehicles. The company has introduced new production techniques and tooling, and a range of innovations, from smaller batteries and motors to a new way of thinking about handling and suspension technology.
There aren’t any drastic or ground-breaking changes, but instead, a holistic approach to current EV development and an analysis of the areas where it can be improved. The new 0 Series, starting with a low-slung sedan based on the Saloon concept shown at the CES trade show in January, doesn’t just signify Honda’s commitment to making EVs in North America, it shows that the company is aiming to become a global leader in EV manufacturing.
Canada will become an important part of Honda’s EV supply chain, from sourcing raw materials for batteries to assembling the finished vehicles. Honda’s investment of $15-billion is the largest of any automaker so far. Along with a new dedicated production plant for EVs that can churn out 240,000 vehicles a year and a separate hub for manufacturing batteries in Alliston, Ont., it will also manufacture cathode active materials and separators at two other sites. The materials used to make cathodes typically consist of a metal oxide like lithium iron phosphate. Separators essentially separate the cathode and anode but allow ions to flow through. They are usually made from polymers like PVC or cellulose.
Production of the as-yet-unnamed sedan will start in late 2025, initially sharing a production line with Honda’s gas cars at its manufacturing complex in Ohio. A newly developed mega-casting machine currently undergoing testing in Tochigi, Japan will be brought to the Anna, Ohio engine plant to produce the aluminum case that will hold the battery modules. Honda says it will eventually install six of these machines, each the size of a small building more than nine metres high.
The mega-casting machine uses 6,000 tons of force to stamp out the battery cases in two separate pieces. One of the pieces can be interchanged, depending on the size of the battery going into the vehicle. This flexible-cell approach can produce cases for EVs of different sizes and reduce the number of parts required to build the case to just five from 60, Honda says.
The battery case is joined together using friction-stir welding, a process Honda has been using and refining since the early 2000s. Friction-stir welding fuses metal without melting it, resulting in a less porous and stronger weld. The tool resembles a drill bit, spinning quickly while applying downward force as it moves along the joint line. The spinning creates friction, which softens the metal and intermixes the layers. There’s less heat and less deformation, and the resulting weld is about as clean and neat as I’ve ever seen.
The finished aluminum battery cases with cooling jacket.Courtesy of manufacturer
Friction-stir welding is also used when joining the cooling water jacket to the assembled case. The result is a battery pack that’s 6-per-cent thinner than its contemporaries. That might not seem like much, but it allows for a lower placement of the pack in the body, increasing space in the cabin and lowering the centre of gravity.
Honda has also developed welding technology that the company says will revolutionize spot welding. Constant Direct Current Chopping welding combines the best of AC (alternating current) welding and DC (direct current) welding, the company says. It can join multiple steel sheets of varying thickness, including lightweight ultra-high tensile steel, while reducing weld spatter to just 2 per cent from 98, the company has found. The resulting weld is stronger and more consistent. Existing robots can be retrofitted with the welding tool and the technology will eventually be expanded to other Honda vehicles, including gas-powered ones, it says.
Honda will use the new process to join sections of the frame in the 0 Series, which can be made with lighter and stronger materials, thanks to this welding technology. Honda says these frames will boast increased protection for passengers and the battery pack during a collision.
This structure might be super strong, but it’s also designed to flex, improving handling, the company says. While many sports cars boast ultra-rigid chassis for handling gains, Honda says that its flexible body structure increases the load on the tires during cornering, and its simple construction saves about 100 kilograms of weight (compared to the company’s first EVs).
Further weight savings are realized with smaller electric power units developed by Honda and built by Hitachi Astemo, a Japanese company specializing in electric powertrains and advanced driver-assistance systems. Called an e-axle, it’s the world’s first electric drive unit with a transversely mounted inverter that’s 40-per-cent smaller than the industry standard. The company can mount these units, which also contain the gearbox, lower and farther forward in the chassis, allowing for a shorter overhang and a lower hood. Honda says that will help to improve handling and pedestrian safety, and the lower placement can reduce damage to the car’s body in the event of a collision.
Once production of the 0 Series sedan ramps up in 2025, Ohio will become the foundation of Honda’s EV push. The knowledge gained from those production lines will be transferred to Honda’s proposed EV and battery plants in Alliston, Ont. The company says it will leverage Canada’s abundant resources and clean energy to establish a robust battery supply chain, helping to bring costs down. The battery plant in Ontario will start with the production of lithium-ion batteries — up to 36 gigawatt hours a year — but will transition to solid-state once the technology is ready for the mass market.
From innovative new manufacturing methods to key investments in battery production in Canada, Honda’s ambitious goal of selling only BEVs and fuel-cell electric vehicles (FCEVs) by 2040 and becoming a carbon-neutral company by 2050 seems more possible. Technologies for improving EV production could also benefit the entire industry and increase the chances of seeing an affordable electric car sooner rather than later, which is good news for everyone.
The writer was a guest of the automaker. Content was not subject to approval.