BMW i3 works to put ‘range anxiety’ to rest
AMSTERDAM — Some are touting plug-in hybrids, while others are looking toward all-electric conveyances. Regardless, the thrust is to reduce the footprint the automobile leaves in its wake. BMW’s take is found in its new “i” brand, a subdivision anchored by two electric/hybrid-electric cars.
The i8 combines an electric motor with a gasolinepowered engine, making it one of the world’s premier green supercars. The second car, the i3, takes a slightly different approach — it is a fully electric design that’s available with an optional range extending gasoline engine.
What the two have in common is a platform purposely built to accommodate the powertrain of the future — it was engineered to house and protect the battery as well as accommodate the power electronics and running gear. In the i3’s case, the body comprises a carbon fibre-reinforced plastic (CFRP) passenger cell that rides atop an aluminum structure that houses the battery, electric motor and the brain that keeps things humming along.
In this instance, the i3 gets its motivation from an electric motor that drives the rear wheels through a single-speed transmission, a 22 kilowatt-hour lithiumion battery (only 18.8 kWh is actually used), and an intelligent management system designed to extract the best from the combination. In this application, the electric motor generates 170 horsepower and 184 pound-feet of torque the instant the electric motor begins to turn.
Driving the i3 proved to be every bit as quick as promised — my stopwatch clocked the run from rest to 100 km/h in 7.3 seconds and pegged the more important passing move (80 to 120 km/h) at 5.1 seconds. Both times would not be out of place in a gasoline-powered vehicle.
The bigger difference between the i3 and its conventional counterpart is found in the launch. The pull off the line is strong (the rapidity actually shocked me) and this work ethic continues on through the mid-range and up to highway speeds. More impressive was the manner in which the electronic trickery combined to produce a completely seamless drive.
The i3 has three different driving modes. Comfort delivers a 160-kilometre range after the battery has been charged for eight to 10 hours using a 110-volt outlet. EcoPro and EcoPro+ then increase the driving range by 20 and 40 km respectively, which delivers a maximum driving range of as much as 200 km. That is an impressive range by current electric car standards — Nissan claims the Leaf has a 160-km driving range, although the Environmental Protection Agency rates it at 120 km.
The key is that both numbers were generated under ideal conditions. Throw in a little cold weather and that range drops dramatically — the i3 was showing a range of 133 km on a cool 9 C day, and it dropped in unison with the distance driven. This is a first for any electric car I have driven. Usually, the range diminishes faster than the distance driven.
The different drive modes do affect how the i3 feels. In Comfort, it is perky and peppy, while each of the EcoPro modes knock a little off the edge. The EcoPro+ does mandate a deeper dig on the accelerator pedal, but it did do exactly as promised — it added around 28 km to the driving range compared to the Comfort mode.
An important part of the i3 package is the regenerative braking. Lifting off the accelerator produced enough retardation from the electric motor — as it harvested otherwise waste energy and used it to recharge the battery — that I seldom had to use the brake pedal under normal driving situations. It was an eerie sensation piloting a car through tight city streets without ever reaching for the brake pedal. Mercifully, when the driver does lift off the accelerator the brake lights come on.
The i3 boasts an ideal 50/50 front/rear weight balance and a low centre of gravity, thanks to the battery’s placement.
Along the drive route, two things impressed me. First, the suspension soaked up the sometimes-rough Amsterdam roads without ceding anything in terms of outright agility. A spirited sprint through a series of twisties and around a handling track produced very little understeer and even less body roll. Second, the electrically assisted steering had better feel and feedback than I expected. It was crisp on-centre and it turned in with the right sort of response. In this regard, the i3 is true to BMW.
For those with the need to drive beyond the all-electric i3’s range, there’s the Range Extended model. It features all of the regular i3’s equipment plus a two-cylinder, 647cc gasoline-powered engine. It produces 34 hp and drives a generator. When the battery reaches a predetermined state of charge, it comes to life and maintains that level. The engine is mounted beside the electric motor above the rear axle so it does not eat into the cargo capacity, meaning there’s no downside to having it along for the ride. When the i3 is so equipped, it has a range of up to 300 km. This is more realistic and it ditches the “range anxiety” that dissuades so many potential customers.
The i3 goes on sale in Canada in the second quarter of 2014 and will cost $44,950 for the all-electric model and $48,950 for the Range Extender version.