BMW adds more electron punch to i3POSTED BY Nigel Andretti ON 04 May 2016
BMW has packed more lithium ions into the battery on its i3 electrified hatchback, boosting capacity from 60 ampere hour (Ah) to 94Ah, and increasing pure electric range to as much as 300km.
Despite the range increase of about 50 per cent over the original model, the new battery, supplied by Samsung, is no larger than the 60Ah found in the original i3 and has no significant impact on the model’s performance or practicality.
This allows it to be retro-fitted to the existing i3, which as been on sale since 2014.
BMW says changes to each of the 96 individual cells that go to make up the i3’s battery, including the addition of high levels of electrolyte and new materials, has brought about a considerable increase in energy storage without any change in size over the existing unit.
With a maximum 33kWh of electrical energy when fully charged – some 29kWh of which can effectively be used – the new 94Ah battery provides 11kWh more than the old 60Ah battery, which delivers 22kWh, or an effective 19kWh.
BMW says the new battery increases the i3 efficiency in adverse weather conditions, claiming a range of up to 200km when the air conditioner or heater is in operation.
The new 94Ah version of the i3 retains the same electric motor as the existing 60Ah variant. Mounted at the rear within the rear axle assembly, the synchronous unit delivers 125kW and 250Nm of torque to the rear wheels.
The 94Ah i3 can’t quite match the standing start performance of the 60Ah i3 owing to a 50kg increase in kerb weight brought on by its new battery. Official figures point to respective 0-100km/h times of 7.3sec and 7.2sec.
It is a similar story with 80-120kmh performance, the 94Ah battery equipped i3 taking a claimed 5.1sec against the 4.9sec of the 60Ah battery i3. Top speed of both models is limited to 150kmh.
The energy consumption of the 94Ah i3 is put at 12.6kWh/100km under the EU test procedure, beating out the 60Ah i3 by a 0.3kWh/100km.
BMW says a new three-phase 11kW charging system developed specifically for the 94Ah battery allows it to be charged in two hours 45 minutes on a high powered multi-phase AC (alternating current) charger, which is the same time it takes for the 60Ah at a maximum charging current of 7.4kW.
On standard 240 volt mains electricity at 2.8kW, the charging times are put at 10 hours and eight hours respectively.
When connected to a DC (direct current) charger, the 94Ah i3 takes a claimed 40 minutes to reach an 80 per cent charge. In the 60Ah i3, this takes 25 minutes.
As well as being available for the pure electric version of the i3, BMW confirms the 94Ah battery will also be offered as an option on the i3 Range Extender, providing it with a claimed additional range of up to 150km compared to the 60Ah unit, which will continue to be offered.
This hints at an overall range of up to 490km for the petrol-electric hatchback, which uses a 650cc two-cylinder petrol engine in combination with a nine litre fuel tank to charge the battery on the run.
The 60Ah batteries traded in by i3 customers in preference for the new 94Ah unit will be used by BMW to produce stationary storage battery modules for use in non-automotive applications.
Pricing of the upgraded i3 and the cost of having the new 94Ah battery retro-fitted to the existing i3 has yet to be announced.