12V battery maintenance for dummies when gone for weeks

I would have someone whose is mechanically inclined or a mechanic - attach a "pig-tail" plug under the hood, at the jump-point. Buy a SMART RV maintenance charger and install the other pig-tail end there. Most maintenance chargers will have a similar optional plug rather than battery clamps. Make sure whatever pig-tail plug and socket combination you use can only be plugged-in in a single direction - so you can't reverse polarity the battery. Most new equipment will automatically do that check, but you kinda want it 'stupid proof'.
Whenever you use this setup; I would recommend that you either leave the hood up or hang a sign on your steering wheel; so you don't drive-off and rip things out of the wall. I always wrap the extension cord around the drivers door mirror - so there's no mistaking that it's plugged-in. If you have a black car, use a white extension cord.

Hope this helps....

PS; your suppose to leave the traction battery charging cable unplugged from the car. That traction pack is suppose to be <50% when you leave the car parked for weeks or months at a time. See long term storage section of your OM.

 

Sounds like you have ac outlets available. I’d connect a smart charger, leave it connected. They run through charge routine, settle down to maintenance charge, can be left on indefinitely. For concerns about connecting wrong way round, just be careful. It’s not that hard.

if possible, get started using it before your hiatus, get familiar with it.

 

if you are nervous about leaving a battery maintainer on your car for weeks, that is exactly what everyone is offering, including the dealership.
if you can't get past it, learn how to disconnect the 12v negative cable. it's about the easiest thing you can do on a car.
and read up about prime 12v problems. there are a lot of them, and a lot of threads.

 

I'm using a CTEK 4.3 (rough equiv now is CTEK 5). It's been in near-constant use getting close to a decade now (we drive very little), and no problems. That said, the NOCO Genius are very popular, and the CTEK's prices have soared.

 

I turn off the water every time I leave the house. I can easily do so, with the aid of electricity.

I don't know about surge arrestors, but flipping the main breaker, if it could be performed effortlessly, as well would be an interesting concept. Unless the place needs to be heated or cooled.

My sister told me a story over Christmas. She was sitting in her kitchen, and all of a sudden water came pouring out of a kitchen cabinet. A Qest (polybutylene) fitting for the dishwasher had split. She figured out where the main valve to the house after a little while. If she wasn't home, could have done much damage.

I wonder if one could have the wiring inspected for incipient faults? They have fancier breakers now that detect sparks, right?

Then too, there's the natural gas (or propane) line. California people probably have that figured out, with the earthquakes and all. I'd think you'd want to have that shut off automatically in case of fire or shaking. While I have propane for the standby generator, I do have a cooking gas line going into the house. I suppose I could rig up a shutoff valve tied into the smoke detectors via home automation. Hmmm.

 

Keep in mind that if you disconnect the battery; you'll either need to leave the trunk lid up or hook-up a jump-pack to open that trunk again. The trunk release mechanism is electronically driven. Removing the battery from the equation will disable the release; so you'll need to introduce power at the jump point or crawl back there to reconnect the battery cable.
Not an issue on gen4 Prius, since the battery is located under the hood.

 

Of course, if it's in the garage you just have to make sure it doesn't latch (tape?).
Things may have to be initialized, apparently-it's in the back of the manual. No big deal.

 

@ChapmanF describes a third gen, under-the-hood disconnect method, here. It entails disconnecting the large diameter, white cable at the fuse box. Maybe be applicable to other gens. Third gen pic:

 

this is what i use while we're in florida
30 bucks on amazon

 

Now that you drew down your battery, requiring a jump, It won't have the same capacity that it use to have. Every time a heavy draw-down happens, your chipping away at the battery's' longevity.
You've got a solid plan in place; but leaving the 12V battery plugged into a "smart" automatic battery charger; would be easier on all parties involved.

 

Like @bisco I use several Noco Genius 1 (1 amp) battery maintainers on multiple vehicles. I have them on a pair of vehicles that are driven about 2 months out of the year and also use them on the Prius and Camry when on travel. Absolutely no issues on any of the vehicles. Just unplug the Noco and start the vehicle as if you never left.

The Noco Genius 1 is about as low power as you can get if you are worried about fire issues.