Working with engineers at Bosch Automotive, BMW AG is rolling out a fast-charge system that could replenish the battery of its i3 electric car in just 30 minutes.
Known as the BMW i DC Fast Charger, the new device represents another step in BMW’s plan to pave the way for wider acceptance of electric cars. “Yes, we are a car company, but we recognize that it’s not enough to just put a vehicle out on the market,” BMW spokesman David Buchko told Design News. “We understand that broad adoption of electric vehicles requires that we make life easier for electric car owners.”
BMW i DC Fast Chargers, developed with Bosch Automotive, are half the size of current DC Combo fast chargers and more affordable, BMW says. (Source: BMW AG)
The new charger, which operates at a maximum of 480 VDC, is targeted at public charging stations, such as roadside rest stops, mall parking lots, and municipal parking spaces. It will not be available for home use.
BMW and Bosch designed the new product to fill a special niche in the EV charger market. The new charger is comparable in size to, but much faster than, so-called “Level 2” chargers, which can take three to four hours to recharge an EV battery. At the same time, it is about 10 minutes slower than today’s DC faster chargers but is about half the size.
BMW’s i3 will use the new i DC Fast Charger. It offers an EPA-rated all-electric range of 81 miles. (Source: BMW AG)
Bosch’s specs say that the charger, which costs less than $10,000, can provide the i3’s 22 kWh lithium-ion battery with an 80% recharge in 30 minutes. It is designed for a three-phase power supply, at 30 A per phase. Input power is 24 kW -- about half that of conventional DC fast chargers.
”For a business entity that’s looking to install a conventional Level 2, 220 V charger, this provides an alternative,” Buchko told us. “It can be installed in roughly the same amount of space. And for not much more investment, it can recharge a car in 30 minutes instead of three to four hours.”
BMW’s i DC Fast Charger can charge any electric car that uses the Society of Automotive Engineers’ SAE Combo 1 standard connector, which includes EVs made by GM, Volkswagen, and Ford.
Buchko said that BMW initially plans to install the new chargers at its dealerships. Eventually, the automaker hopes to partner with business and government entities on installation at public charging locales. “We don’t have a schedule for a broader rollout,” he told us. “But we are pursuing it quite aggressively.”
Ratsky is definitely correct. Overcharge is an issue. That's why we hear about 80% charges during fast charges. Engineers compare it to filling a coffee cup -- you can put the first 80% in real quickly, then you have slow it down as you reach the brim of the cup to keep it from overflowing.
What happens to the charging capacity (in terms of cars per unit) when some zealous EV owners start getting to the public charger at say 5am and then work 10 hrs, plus takes a 1 hr lunchs and in doing so tie up the chargers for 11 hrs?
Just a thought.
But I do like the 30 min charge time. Maybe it could be designed to spit out and retract the plug at full or some other predetermined charge/dollar amount. Could reduce the number of "punched in the nose" scenarios discussed in the posts on this board.
OK, so i did a little searching. Battery University has the following explanation for what happens when you overcharge a LiIon battery:
"Lithium-ion operates safely within the designated operating voltages; however, the battery becomes unstable if inadvertently charged to a higher than specified voltage. Prolonged charging above 4.30V forms plating of metallic lithium on the anode, while the cathode material becomes an oxidizing agent, loses stability and produces carbon dioxide (CO2). The cell pressure rises, and if charging is allowed to continue the current interrupt device (CID) responsible for cell safety disconnects the current at 1,380kPa (200psi).
Should the pressure rise further, a safety membrane bursts open at 3,450kPa (500psi) and the cell might eventually vent with flame."
... maybe it's just me, but the (understated) term "vent with flame" doesn't sound like a good thing!
@ fm: Multiple mechanisms involved. I don't know the details, just the warnings I get from the vehicle manufacturer (these are earlyish prototypes). Explosion and fire are the biggies, but drastic reduction in capacity is something we actually experienced more than once. All due to SW bugs in the charge manager that subsequently failed to properly protect the battery packs.
I think my old boss's house is 3-phase. It's really more like a mansion/compound on 35 acres.... completely computerized automation. He hasn't sprung for a true EV yet, though. Drives hybrids and has for years. Likely main reason is range as he lives WAY out in the countryside.
The charger will be available to any car that uses an SAE 1 standard connector, naperlou, which would also include GM, Ford and VW. Japanese automakers, however, are leaning toward the Japan-developed CHAdeMO standard connector.
Tesla Motors’ $35,000, 200-mile electric car may not revolutionize the auto industry by itself, but it could serve as a starting point for a long, steady climb to a day when half of the world’s vehicles will be plug-ins.
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