Nav & Search

The BMW Mini-E and the Launch of Electric Cars

Miscellaneous

Where some (GM Volt and Tesla Roadster) are fumbling to get their electric cars out to consumers, others are continously presenting concept models that will never see production (Volvo ReCharge) and some just don’t do anything at all (Mercedes). During this time though, BMW have remained quite and almost seem ignorant of the environmental and regulatory challenges lying ahead for the auto industry. BMW has sneaked up behind everyones back and will deliver 500 electric Mini-Es to customers in Los Angeles, New York and New Jersey from the end of 2008. The electric car is the automotive future and this surprising move by one of the most dominating players is a most welcome one bound to fuel the fire for the other major manufacturers.

BMW Mini-E

The BMW Mini-E. Photo by BMW.

Since the beginning of the millenium most manufacturers have searched, tried and launched a variety of technologies and research projects in search of better fuel economy and less emissions (particularly green house gases). The different paths have been fuels (diesel, ethanol), hybrid systems (Toyota/Lexus Hybrid Synergy Drive) and various techniques toboost thefuel efficiency of gasoline cars (direct injection, cylinder deactivation, variable valve timing). These are all very welcome but all without exceptions fail to reach the ultimate target of zero emissions.

The only known technique to propel a vehicle using stored energy andzero emissionsis through an electric motor. The energy can be stored in electric (batteries) and chemical (hydrogen through fuel cells, gasoline by using an ICE generator) form. Only one of these options has a future as a primary energy storage solution. Guess which?

Chemical energy storage will play an importantrole as a range extender for the near future simply because batteries has yet to have sufficient energy density (per volume and per weight) and charge speed to allow us to use our vehicles in the way that we’reused to. Eventually though, the only option is to use batteries and the companies following the hydrogen route are following a path to a dead end. Hydrogen is dead simply because it ismade using electrolysis, basicallymaking it a very inefficient, expensive and lowperformingbattery. ICE generators has some merit, particularly when driven on bio-fuels. They allow electric cars to have the same range as conventional cars while allowing the car to use energy from the grid most of the time. Eventually though, increased energy density in the batteries will make them redundant and only add weight, cost and complexity to the vehicle.

Therefore, BMW has made the right choice in launching a large scale public test platform with the Mini-E. Their move isa contained economicrisk due to the unknown problems that may arise during long-term use of new batteries, but it will catapult BMWs battery and electric drive knowledge several years ahead of its competitors. BMW have been notorious for keeping out of the green car market, their only sub 120g CO2 vehicle being the Mini-D. GM could havehad a head-leap to BMW and in some ways Toyota (due to their experience of batteries in their hybrids) but instead scrapped their EV1 program 8 years ago under suspicious circumstances (find and see “Who Killed the Electric Car?”).

After a couple of years with different manufacturers presenting and unveiling concept cars and pre-production models the Mini-E was publicly unveiled at the L.A Auto Salon. The 500 cars will be delivered starting from the end of 2008 to regular customers in the L.A and New York areas on a lease program costing $850 per month.The base cars are builton the standard Mini production line in Oxford while the electric components are added in Munich and are scheduled to be finished before the end of 2008.

The Mini-E has a 35kWh 380V (nominal) battery consisting of 5,088 lithium-ion cells arranged in48 modules split over three separate packages. The aircooled battery weighs in at 260kg bringing the total kerb weight of the car to 1465kg,a little heavier than a late VW Golf instead of the nimble 1132-1175kg of a petrol-engined Mini. A positive side effect of the extra weight is an improved weight distribution, it is now close to 50/50 with 750/715kg front/rear. The battery is capable of being charged in 2.5 hours using a high-amperage wall-box supplied and installed in the owners garages, a normal U.S outlet can charge the the battery in 8h. To extend the lifespan of the battery it will never be completely depleted, a maximum of 28kWh is drawn during a full recharge.

The Mini-E uses 0.12kWh/km which gives it a range of 240km which is more than enough for the intended application which is urban commuting. The rear seats are removed to make room for the battery which further emphasize that application. Power is delivered by a 150kW (204bhp)electric machine which can produce 220Nm of torque from idle. The EM can spin at a maximum of 12,500rpms which limits the top speed to 152km/h since they have skipped to use a gearbox; a lesson learned from Tesla? Although not a race car, the acceleration is a rather quick 8.5s 0-100km/h positioning it between the 175bhp Mini Cooper S (7.1s) and the 120bhp Mini Cooper (9.1s).

Has BMW made the right move? Absolutely, this move accelerates BMWs R&D and brand as an environmentally aware company that gives its customers what they want. Have they made the perfect city car? No, not yet, the price is too steep at $850 per month for a two seater city car. Given BMWs dedication to performance, I’m really excited to see where they move from now on though…

References:
BMW Mini-E Press Release
Mini-E Specifications (pdf)



Leave a comment

Your email will not be published.

*