12 volt batt adventure

Read the previous post. If you aren't going to read the answers, it's pointless to ask questions.

Tom

 

Did not see this when I posted--thanks--amazing post, just what I needed!

John

 

Further, the ground bolt is just behind the battery, just below the tail-lamp assy.
Easy to access, just remove the hatch floor and tray, then remove the section in the far right which is a cover over the battery. No tools required.

 

The 12v battery has a nonstandard terminal post diameter. Rather than buy a battery from the dealer or use a retrofit adapter, I used a hacksaw and then a file to quickly downsize the terminal post on my cheap replacement battery. But remember, you're creating lead dust when you do this. (I won't even mention the additional problem of venting the replacement battery. If the battery compartment is unvented, the battery terminals will corrode drastically with copper sulfate. I don't know whether putting copper pennies in the compartment will effectively draw the sulfuric acid fumes away from the terminals.)

 

I'm new to the forum and apologize in advance if my problem has already been addressed. I have a 2009 Prius that will be 2 years old in June. For the first year, I had absolutely no problems because I never had to let it sit for more than a work day. This past year, I've been away a few times and had to leave it in my garage for a week or so. Upon my return, the 12v battery was dead as a doornail. The dealership told me to have AAA charge the battery just enough so that it could be backed out of the garage, put on the flatbed and taken in. Both times, the service department told me that the battery was bad and that they had replaced it.

This last time when I called, I was told that "it happens" and that I should have someone "take and drive it around every few days." There is no one I would entrust with my car, so THAT wasn't an acceptable answer. I asked about a trickle charger when I'm away, and they responded that "it couldn't hurt."

I searched for and found this blog, which has been very helpful. Jayman said in one of his posts that a trickle charger won't cut it, and that Toyota says to use a 10 amp 12v battery charger. He also said that he hooked up and has been using a 12 vdc Battery Minder when he's not using his car.

I'm going away again and want to get a Battery Minder so that I don't have to call AAA again. After doing some web research, I found that a BatteryMinder Plus seems to be what I need. I don't know a thing about cars and I need some help here.

It seems that there is a 12v BatteryMinder Plus that can be set for 2/4/8 amps. Is this the same thing as a 12vdc charger, and will 8 amps be sufficient? I feel like a moron asking such a stupid question, but I want to buy one before I leave on Wednesday, and I could really use some advice! Can anyone help?

 

Yes, that product will serve as a charger and should nicely meet your needs. Note that a warning label on the 12V battery suggests a maximum charging current of 4A.

 

Many thanks!

 

I replaced mine with a wet cell that is unvented in the prius sense. That is no vent tube. The battery terminals were also the right sizes. I removed the vent that goes over the 12 Volt, so the total amount of cooling air travels thru the HV pack as well as flowing over the 12V and out the 2 exaust on the right rear fender. So far no problems and no corrosion? But, this has only been for about 6 months. A normal, healthy wet cell emits a tiny amount of pressure thru it's vents in the caps, that is basically a safety precaution. It would be interesting to tie some pennies from the chassis to ground, although it may only work if the car was immersed in salt water!:rockon: