From what I've read, the cold is much worse for batteries than warm is. Up to a 40% decrease in battery life in cold temps. Lucky in battery testing range for cars, they don't test in Minnesota or the North Slope.
There's lots of issues with electric for construction equip, vs in a commuter car. For the dirt working guys, there's usually no outlet on the site when they show up. Nobody is loading the equipment up every night and hauling it back to a power pole, moving equipment from site to site costs $$$. In a commuter car, you start it up, drive your 20-30 minutes to work, then back home again. AzIron is going to beat a electric backhoe with a hammer for 10 hours straight. A farmer in North Dakota is going to go out to a tiling job, and he wont see a power pole within 10 miles of him, let alone a outlet.
Electric is gaining a foothold in London, where they have strict emissions requirements, and the built up infrastructure. That's where electric is going to have to start, in the LA, Chicago, New york City and industrial/factory work.
Also, I'm your market guy for a electric. I run cranes, and the new dpf systems like to be run hard, and on the jobsite we don't run very hard. Lots of idling time, and the new engines aren't taking it very well. But I don't want all electric, I'm trying to move 100,000lbs machines down the road. I want a big 400hp 1800ft.lbs torque diesel motor in the carrier to drive down the road, and a 4 cyl, diesel electric hybrid upstairs to run the crane, like a Prius. Battery gets low, the engine comes on to charge it. I'm sitting there holding a piece for 3 hours, and I get to run on battery power. Working hard and my genset diesel kicks in. I would even settle for running the big engine to charge the battery if I had to. New 100 ton plus cranes are expensive to start with, so there's more $$ margin to work with to add the cost of a electric system. Whereas the skid loader market is much smaller $$$, and very competitive on price.
As far as fuel usage, I'll burn around 20-30 gal in a typical day with my 300hp smaller cranes, my bigger cranes can burn up to 50-60+ gallons.
I'm probably the closest one here on idling 50% of the time. For most equipment, time is money, jobs are bid, and the equipment has to be moving to be making $$$. Idling is really hard on the new emissions systems, so the manufacturers are all about shutting off equipment that isn't working. So very little equipment is going to have that much idle time.
I see electric taking hold first in the crane, manlift, and telehandler world. Then working its way to the dirt equipment and long haul trucking. But I think hybrid ICE with battery, makes much more sense, and would be much more readily accepted than straight electric.