Gen 2 2008 12volt battery question

I don't know Just look online for our battery size there are some options I think they're all about $180 if you shop carefully the die-hard in the silver blue label looking business maybe with gold writing of die hard so that makes it a die-hard gold I bought one not long ago for 184.63 carrying it out of the store brand new That's a reasonably good battery in my book they do make better but there's no reason to spend that kind of money on such a small 12 volt there are other tricks other people are using some are using elevator batteries The batteries that go in those boxes that turn lights on when there's a fire in the building they called them UB universal batteries but I don't think you want to get into all that business you just want to straightforward swap and that'll be the way to go so give that a try That's a little bit less than your 250 for the diehard.

 

Check your local Walmart for the 12v battery. In my area it costs $180.

 

some people use a small inexpensive tractor battery or the like. you would have to alter the hold down bracket, and possibly the terminals rings.
there are a few threds here if you can find them.
how old is your 12 volt? does the car start?

 

How does one assess Dr. Prius the condition of a 12V battery?
The condition of the battery is assessed by the voltage after charging it.
Or a special device that determines its internal resistance in conjunction with voltage.

 

I don't trust these small electronic testers very much. Our 2007 had been on a lot of short trips lately and the Viking tester

12V Digital Battery and System Tester

put up a "replace battery" with a set of terrible numbers, 12.3V and SOH 10%, capacity 7AH, and so on. So I charged the battery for most of the day and retested it. 12.55V, SOH 90%, capacity 45AH, and all good.

But it wasn't apples to apples. The first test was attached at the front jump post, and the second attached to the clamps on the battery (where the charger had been attached). This tester can make mediocre electrical connections:

What causes the voltage drop between the 12V and the jump post? | PriusChat

and I don't think it did a great job clamping onto the jump post. That wouldn't have affected the voltage measured, but the internal resistance and load testing (such as it is) was probably not very accurate.

Note, in both cases the test started about 1 second after a 20 s discharge with the headlights, so there was some voltage depression factored in, I didn't let the battery rebound to whatever its original voltage was before running the test.

 

Those electronic testers assume that the battery has been fully charged before it is used to test a battery. This is the case for all battery testers. To not charge the battery makes the 'test' meaningless.

A better tester (IMO) would be one of these (or similar) – CEN-TECH 100 Amp, 6/12V Battery Load Tester. Only 20 bucks.

 

Information comes to mind.
After charging the battery, you "replaced battery" it for the tester.

 

Don’t ask…

I’m using a Solar BA5 (a resistance style tester). Its manual does not mention a need to charge, nor does the state of charge seem to matter. It will deliver a verdict of “good but needs charging”.

Also manual says emphatically that clamps HAVE to be directly on battery posts. I’ve found in practice if that’s hard to accomplish clamped to the clamp at the post will work as well. Anything else, say like Prius jump point, it gives an error message.

 

Regardless, you will get a better quality test if the battery is full to begin with.

 

Maybe. The Solar BA5 gives the same CCA value, before and after charging (plus/minus one or two I suppose). Current itteration is BA9 I think.

He compares various tester styles, including the one you linked.

 

I don't recall the "manual" saying that the battery needed to be fully charged first. Since it is a HF manual, it consists mostly of safety disclaimers (OK, only a page or so in this instance) and some vague directions. Here it is:

https://manuals.harborfreight.com/manuals/58000-58999/58759-193175446282.pdf

It does say

The heavier duty testers at Autozone and the like don't need a full charge, but they need a substantial charge. Makes sense because those actually put a significant load on the battery during the test. (Hence the large case, vents and in at least one instance, audible cooling fan.)