Just because it's cold outside doesn't mean the truck is cold. Sure it'll be less efficient starting off in the morning, but once it gets going it'll warm up quickly. The truck might be 92% efficient at turning electricity into motion, but 8% of 1.7kWh/mile gives you 130W of heat.
One issue with most lithium chemistry is that it isn’t rechargeable below freezing - it causes permanent damage to the pack.
Practically speaking, this is solvable using in-pack heaters which divert the charging power to warming up the pack first. This takes time if it’s been allowed to sit. Laws of physics and all.
Charging these batteries is also going to take time, a lot of it, and significant charging infrastructure.
Short haul might go through a tank a day, but long haul often uses two drivers working in shifts and can cover 1000+ miles a day easily. It takes 30 minutes or less to refill a diesel long haul truck.
Unless they can get charging times down to an hour or less (which if it is a 875kwh pack like some folks think, that means literally megawatt sustained charging rates), it would require a major change in how long haul truckers work to have a chance.
Current superchargers max out at 250kw, which at max rates would take 3-4 hours to recharge, and they require a decent amount of expensive infrastructure to be able to support that.
Not only did Tesla announce Megawatt chargers they claim will do 70% charging in 30 minutes, but this isn't a sleeper cab, so you're not going to have two drivers doing shifts anyway. And there's no need to worry about the pack freezing during use. The pack can be thermally insulated and the temperature is typically controlled via a coolant loop, possibly using a heat pump to maintain temperature. They're also typically automatically pre-heated before leaving.
If you plug in to charge immediately after driving, the temperature issue isn't a problem as both charging and discharging the battery produce some heat.
(Additionally, the "can't charge below freezing" is a chemistry-dependent thing... it's really only essential for certain chemistries like lithium-iron-phosphate, not the type they're using on the long range Tesla Semi... although acceptable charge rate does reduce at lower temperatures due to lower charge-carrier mobility IIRC.)
Stopping for 30 minutes to add another ~350 miles to the range will mean that a driver won't be limited by the truck in how long they can drive in a day. Additionally, charging is way safer than pumping diesel fuel, so drivers don't need to tend to their truck during charging (unlike fueling), freeing them up to rest or clean up or eat.
Tesla has done an excellent job installing Supercharging infrastructure in the last 10 years in the US (better than everyone else combined, although it's getting better), so installing Megacharging infrastructure seems like something they'll be easily capable of.
