Plan on not using car for 2weeks or more

schabelf said:

I have an old truck that has a current leak some where and rather than try and find it I just installed a kill switch on the battery. If the Clarity is prone to have the 12 volt battery discharge if left sitting for 2 week (or less) should you disconnect the battery before leaving it? Will this cause any damage?

Click to expand...

Some people have experienced that the 12V battery on their Clarity died after a week or two of the car not being used. Others have gone much longer with no problem. It's possible that the ones that died the 12V battery was already weak.

Putting a battery tender on as already mentioned is generally the best method. Battery Tender is actually a brand, probably the most popular one, but there are others.

Removing the negative cable from the 12V is okay also, although it will reset your history so your estimated EV range will be off for the first few drives while it builds history back up. Also whenever the 12V is disconnected, the next time you start the car there will be all kinds of ominous warning messages about ABS and several others, this is normal and those messages will clear within the first mile of driving.

Another option, if you will have access to the car and just won't be driving it, you can turn the car on to READY mode for about an hour every few days, this will charge the 12V battery.

Another option is to do nothing and just be ready to give it a jump start if needed. Although if it requires a jump start then probably the 12V is weak, and draining it down will accelerate its eventual demise. But I guess maybe that's one way to test the condition of the 12V battery by seeing if it will survive two weeks without charging! As a side note, the portable jump start batteries work quite well especially on hybrids as hybrids don't need a lot of power to start, the lithium portable jump start batteries are small enough to fit in the glove box.

Trolle said:

I have used a pair of these for years.....Automatic Battery Float Charger (harborfreight.com)

Before getting them I had an expensive Battery Tender brand that died in 1 year

Click to expand...

One thing I started doing is to not keep the battery maintainer plugged in all the time. I have a car that I don't drive very often and like most people I was keeping the maintainer connected and running all the time. That works, and it might run for several years, or it might burn out after a year or two which can happen with any brand. Then I read a comment by someone who said they put the maintainer on only until the battery is charged, then they unplug it. They would do this maybe once a week, or twice a week or whatever. That should help the maintainer last much longer, especially since things tend to be made cheaper nowadays. A brand that used to be solid in the past can now be more hit and miss. I have owned many things that ran for years, I didn't worry about them going out because I thought if they do I'll just get another one and it will also run many years, but you can't always count on that. And even if it is solid, the more reason to try and extend the life.

Actually they said the main reason that they didn't keep their maintainer running all the time was because in their experience in car repair they had seen cases where as battery maintainers got older they sometimes became defective, and instead of just dying they would start overcharging the battery, which besides shortening the life of the battery can also cause acid to leak out and cause corrosion damage. Maybe the odds of that happening are low, but for both of those reasons I decided to follow that strategy, after the battery is fully charged I keep the maintainer connected to the battery but I unplug the maintainer from the wall. I do this about once or twice a week. If someone thinks that is too much effort I can understand, and probably it will be just fine to run it all the time, but that's what I do now since it's pretty easy to do.