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2 February 2010

It seemed as if the Enerdel company had maybe built a massive wind farm in the middle of a random field in an even more random part of Indiana (itself a pretty non-descript state) just so visitors coming down from the north would think “Gee golly, maybe these electric cars do have a chance.” That’s what I decided at least, as I passed the Fowler, Indiana, exit and the seemingly endless array of giant, futuristic windmills that loom over century-old farmhouses just off of I-65 on my way to Indianapolis, a place with great history in motorsports and a blossoming future in the electrification of the automobile. It’s here that Enerdel, a lithium-ion battery producer that recently announced a partnership with Volvo, is based.



Interestingly — and somewhat ironically — the Enerdel assembly plant that hopes to provide power to countless future electric cars once housed GM’s engineering team responsible for the failed EV1 electric car. And the company’s name is actually a fusion of two: Ener1, Enerdel’s parent company, and Delphi, as in the bankrupt GM supplier. It was a joint venture formed in the early 2000s that shifted to full Ener1 ownership when Delphi was desperate for cash and looking to shed assets. With such ghosts of electricity past lurking around the building, we’ll bet the workers don’t like to be there alone at night.



But on to the present, and how our visit to middle Indiana pertains to Volvos. Last year, the brand from Gothenburg announced future vehicles that will use large lithium-ion battery packs as either the sole or primary means of propulsion. The first concept was a V70 plug-in hybrid, and the second was the C30 electric car shown last month at the Detroit show. They also announced a partner that would be supplying the batteries, and that’s Enerdel. The company operates the only volume-ready lithium-ion production facility in the US, driven by CEO Charles Gassenheimer’s motto that “replacing foreign oil with foreign batteries is not a sound idea.” The man in charge also commented on the importance of growing capacity, stating that putting 100,000 electric cars on the road this year would take today’s entire capacity of lithium-ion production, worldwide, and with all companies combined. As such, a new Enerdel plant will open in Indiana next year. But I’m here at the current facility, where I’m able to get a walkthrough of a C30 battery pack’s construction from start to finish.



There are two types of lithium-ion batteries: prismatic and cylindrical. Cylindrical-type cells are round, like the batteries you put in your remote control. They can be a pain to package because their roundness leaves a lot of dead space when they’re grouped together. Enerdel produces only the prismatic, or flat type, the same you’ll find under the back cover of your cell phone. Either way, each individual container is called a cell.



Battery cells can be broken down slightly further, into electrodes. The transfer of ions between the negative and positive electrodes is the event that delivers electricity to, in this case, the motors that drive wheels of a car. In prismatic cells, these electrodes are stacked, negative on positive and so on, with a thin layer separating them to prevent a short. I watch as a machine starts with a giant roll of foil, which it spins into a device that applies a black film to each side of the metal to produce raw rolls of electrode. The roll is then cut to the dimensions of the final cell, and the components are transferred to a dry room for cell assembly. Contamination and moisture are enemies of a properly functioning battery. The cut electrodes are piled up, 13 positives and 12 negatives, taped tight, and slid into the bag that is the final cell. They are then vacuum-sealed and packed with electrolytes that allow the chemical action to begin. To keep the company’s secrets safe, the whole process is made out to seem like something a kindergartener could do, but there’s a lot of chemistry behind the scenes.



Different chemicals can make up the positive and negative sides of the equation, and the results deliver varying compromises between power density and energy density, meaning power versus longevity. Hybrids, for example, usually get a sprinter-style battery, a mix of hard carbon and mixed oxide that delivers lots of power but less energy. Electric cars, however, need range and use hard carbon and, in Enerdel’s case, a lithium manganese oxide that provides more energy per cell. Is your brain hurting yet?



Once the cells are constructed, charged, and tested, they’re assembled into modules, which are then laid out into the huge packs that end up hidden, in the Volvo C30’s case, inside the transmission tunnel and out back, where a fuel tank would usually reside. Those modules are about the size of your typical 12-volt car battery, but inside each is a row of cells, each less than an inch thick, bolted into small cartridges with metal fins that serve as part of an eventual cooling system. In all, the C30’s two packs use a combined total of 400 individual cells.



That might seem like a lot of cells, but compared to the Tesla Roadster’s 6831 cells, it’s nothing. Fewer cells, Enerdel says, means fewer connections and reduced opportunity for failure. And combining them into these off-the-shelf modules means costs are lowered, thermal performance is predictable, development time is shorter, and serviceability is better. If one module of a larger battery pack acts up, it can be individually swapped out. I watch as a plant employee drops a set of cells into the outer module container, then a top goes on, which houses some of the electronics that monitor battery performance.



The final step is taking the modules and dropping them into a larger metal container to produce the final pack. Inside, the modules divided up in halves and each half is wired in series. The two halves are wired in parallel, allowing the electric car to continue limping home even if one series of batteries malfunctions. There’s a whole series of safeguards and redundancies inside the batteries for safety’s sake. A battery management system, or BMS, oversees everything happening in the cells, like balancing the amount of power coming from each one to optimize both life and capacity inside the battery. The BMS monitors temperature and contains crash sensors, which will cut the battery off from the rest of the car in the event of a collision. Additionally, the battery packs have a cooling system, a series of vents optimized to deliver equal cooling across every cell. Enerdel does it all, starting with raw ingredients and ending down an assembly line with a complex, futuristic technological marvel that’s little more than a plug-and-play ordeal for Volvo.



A Volvo C30’s Enerdel battery pack should be good for about ten years of service in a vehicle. What I’m able to take away from witnessing the pack going together is that the process isn’t too labor intensive — we only saw a few dozen people running the machines and doing a little bit of hands-on work with the batteries — but instead very material intensive. The raw solvents and elements, the plastic and wiring and metal and hardware, the electronic management systems, it all costs money. The going rate, I’m told, is about $750 per kilowatt-hour. The Volvo pack is about 24 kWh, so that equates to $18,000. Yikes.



So how will those prices come down? And what happens when the battery needs to be replaced in ten years? Both of those questions share an answer, in a way. While the batteries are no longer suited for vehicle use after a certain time, they aren’t useless. This “secondary use market” is said to be the next big step in making batteries more sustainable and more cost-efficient. The idea is to take used electric or hybrid car batteries and plug them into grids to serve as storage facilities. During the night, when power plants are off-peak and inefficient, electricity can be stored in huge containers of these batteries to be used later, during peak usage times. This would chop the top off those peaks, lower the cost of energy, and make plants less wasteful. Batteries then could be leased, or simply sold for less to consumers, with the expectation that they can be turned in and sold for secondary use. After more time elapses, when the batteries become less useful, they can be recycled and reborn. As a long-time hybrid doubter, this whole idea has me reconsidering the concept. Volvo has some more specific plans for its battery packs, which our SWEDESPEED affiliate covers in greater depth, along with some thoughts on batteries and safety issues.



I leave Enerdel disappointed not to get any seat time in an early C30 prototype, but nevertheless excited about the future. I have driven the Mini E and found it to be surprisingly normal to drive, and expect the same of the C30. However, there are still many hurdles between these cars and full-on series production. Charging times, with “overnight” being the common answer to the question of how long, are unrealistic for some people. A range of around 100 miles is good for most commuters but eliminates the possibility of any electric road trips in the near future. And of course there’s the cost, which I already stated was staggering. I left Enerdel, however, with the comfort that these people are eager and passionate about the potential of their products, and with major partners like Volvo on board, development should progress quickly.



How long will it be until you can plug an affordable C30 into your garage, take off on a vacation, and be able to quickly charge it along the way? That’s probably some time off into the future. But starting next year, Volvo will put a small batch of them in the hands of commuters across different climates and different driving conditions. And that’s a start.


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