You can take a break from field work every few hours to charge your electric tractor! What a bunch of crap. I cannot imagine trying to farm this way.
It does say for tasks like loading/towing/transport it could last up to 8 hours, but yeah 3-4 hours for tillage doesn't sound great. But given how much my wife's family pay for regular engine maintenance on their tractors I wonder if you could buy 2-3x of these for overlap and still come out ahead (assuming they don't have as much maintenance).
Seriously, her family spent half what my house is worth on fixing two of their tractors.