I tried a search, but maybe I don't have the right search terms.......how much do I need to be concerned about a BEV sitting idle for days or weeks at a time without being plugged in? I'm considering a 2019 Leaf or Bolt, if that makes a difference in the answer.
The 12V is the one that suffers parasitic loss. In some of the Toyota Prius, a weak 12V battery won't be able to start the car after 3-6 weeks. Bob Wilson
Thanks; I'm anticipating that at some point I'll need to leave my car unplugged for 3 or 4 weeks while on vacation. If necessary, I could get someone to drive it to a charging point, but I'd rather not.
A solar charger that uses the OBD port works or just disconnect the 12V ground. Either works but the 12V may require the mechanical key to open hood to reconnect the ground. Bob Wilson
Different cars have different -- sometimes very different -- recommendations for how to handle the issue of being left for weeks without being driven. Quotes from random forum posts: From the owner's manual of my 2011 LEAF, page Ev-3: "The Li-ion battery discharges gradually if the vehicle is parked for a long time. NISSAN recommends charging the Li-ion battery every 3 months using the long life mode charging method to keep the Li-ion battery in good condition. Do not leave the Li-ion battery fully discharged or with a very low charged level for a long period of time." http://www.mynissanleaf.com/viewtopic.php?t=8125 ...and a post on the Chevy Bolt.org forum: The owners manual says the following (pg 259): Quote: Up to Four Weeks . Plug in the charge cord. Four Weeks to 12 Months . Discharge the high voltage battery until two or three bars remain on the battery range indicator (Battery symbol) on the instrument cluster. . Do not plug in the charge cord. . Remove the black negative (−) cable from the 12-volt battery and attach a trickle charger to the battery terminals or keep the 12-volt battery cables connected and trickle charge from the underhood remote positive (+) and negative (−) terminals. See Jump Starting - North America 0 295 for the location of these terminals. https://www.chevybolt.org/forum/82-charging-batteries/9794-storing-car-month-plug-not.html
The Bolt EV and Leaf don't have any issues with parasitic losses. You could leave them for a week or two with no ill consequences. Granted it's always recommended to leave them plugged in (L1 is fine). But in an emergency it shouldn't be an issue.
