Followup to Prius battery woes

[PeterB]

mikebw wrote:
Gotta say, as a Prius owner here I didn't know this about the alternator, as was also mentioned above:

https://en.wikibooks.org/wiki/Automobile...yota/Prius

Recharging the 12 volt battery
Unlike normal cars, the Prius does not charge the 12 volt battery via an alternator spun by the engine. This vehicle charges its 12 volt battery from the hybrid system, so if you are unable to take the car out for a run for any reason, just switching the system on for a while will do the job. To maintain charge in the 12V battery if the car is not being used often, Toyota recommend putting the car in 'Ready' mode for one hour, once per week. If the battery is completely flat, the vehicle may need to be put in 'Ready' for 4 - 8 hours to fully recharge. Be aware that the engine will start occasionally to ensure the high voltage battery doesn't discharge - so this should only be done in a well-ventilated area, not a closed garage. Doing this will also wreck your miles per gallon record. Alternatively, the 12 volt battery can also be recharged using a standard car battery charger.

Good to know that it can recharge the 12v by itself, but for times when you cannot wait it still seems prudent to keep a small jump 12v starter pack in the car.

Wow!! VERY good info here -- that part I've bolded is definitely not what I've been doing, so will give it a try. (Money is kind of tight for me right now, and if I can get away with not having to change the battery for a bit -- especially considering that I'm not doing that much driving right now -- all the better.)

Edit: so this basically means doing the same thing that the other video posted says to do -- essentially starting the car up and letting it idle for 6-8 hours. I could easily do that during the course of the day, just leave it parked and running ... since obviously I don't want to be sitting in the car that whole time, I presume I should start it up, then lock the doors and let it run. I don't really care if it uses up gas, since I have plenty stored away.