Rumors suggest BMW is planning more incremental improvements to better compete with the Nissan Leaf and other upcoming long-range EVs.

BMW is reportedly preparing to introduce another battery upgrade for the i3.

The company introduced a larger battery pack last year, jumping from 60 amp-hours to 94 amp-hours and improving electric range from 81 miles to 114 miles.

A rumor posted by BMWblog now claims the troubled EV will get another battery upgrade in 2018, bringing capacity up to 120 amp-hours. Converting the capacity measurement to the industry standard, the rumor points to a 42.5 kilowatt-hour pack -- on par with the new Nissan Leaf.

Like the new Leaf, the i3 will likely approach 150 miles of EPA-estimated range with the larger battery pack.

BMW recently unveiled the i3s, slightly tweaking the EV's aesthetics but without departing from its controversial overall styling. The automaker is presumably hoping a fresh face and longer range will help the i3 gain traction despite a 23-percent sales drop in the US for the first eight months of the year.