Been having this problem too after years of no problems. New battery did not help at all. This is absolutely stupid that you have to charge two batteries. Definitely something faulty with the whole thing. Time for a recall Nissan.
Starting getting the dreaded T/M malfuction last month. 2012 Leaf just hit 44k miles. Finally got a new battery, charged it up and still getting the error unless i have it on the battery charger overnight. Seems like i have a 2AMP load somewhere when the leaf is off while the leafspy can connect...