Despite a third consecutive declining month of BMW i sales, the sub-division focusing on electric vehicles and plug-in hybrids sold 5,128 units globally. In March alone, 2,225 i cars were delivered. The first quarter i sales are nearly 23 percent less than year ago.

The sale numbers don’t include the X5 xDrive40e, the 330e, 225xe Tourers or the 740e sedan. To revamp sales and offer a more compelling product, BMW plans to introduce a major update to the i3 which will bring a new battery pack.

A larger capacity battery in the i3 will allow for extended driving and it will arrive this year. Instead of opting for a battery replacement, BMW will extend the i3 lineup to offer two additional models – one fully electric with the new battery and the other a REx version with the same technology.

It’s expected that the new models will come with a four digit surcharge.

The current model consists of 8 x 2.7 kWh packs cells – each containing 12 x 3.75 volt, 60 Ah actual cells – wired in series for a nominal capacity of 21.8 kWh, 360 volts, of which 18.8 kWh are usable. The new battery is expected to have a 94Ah battery and the higher energy density will give the i3 an expected range of 120 miles.