Another battery for the Prius.

Here is your link:

VMAXTANKS GOLFCART 12V AGM Dry Cell Battery MB96-1300 | eBay

For some reason the link is grayed out for me as well.

Tom

 

Thanks for the recommendation! I just bought this battery from Batteries Plus in Tucson, AZ, for $164.99 plus sales tax. Compare to the two local Toyota dealers which offer the replacement battery at $214.

The voltage of the battery was 12.37V when purchased so I am currently charging it with a 2A lab power supply set to 13.8V. The battery was manufactured in January 2013 and shipped in April 2013. A new, fully-charged 12V AGM battery should measure 12.9V. (The two 12V AGM batteries that I've bought in the past from local Toyota dealers were fully-charged upon purchase.)

This is yet another example of a newly-purchased 12V battery which is partially discharged, hence I again recommend that owners fully-charge their new 12V batteries before installation.

The reason that I bought this battery is for use as a preventive install on my daughter's 2007. The battery in her car was fully-discharged 2x (due to driver error.) Although it is still working, I don't want her to run unneeded risk of a no-start situation.

 

Pat, do that battery have a vent tube?
Thanks

 

The Exide part number for a AGM battery with an external vent and JIS posts is S46B24R


Exide AGM Car Battery (Group S46B24R)


I did not see that the ebay battery had either external venting or JIS posts.

 

Both ends of the battery have a vent hole that hopefully will accept the black plastic vent fitting. The end near the positive terminal currently has a rubber plug in the hole while the end near the negative terminal has no plug. I need to move the plug to the hole near the negative terminal, since the vent tube plugs in on the side near the positive terminal.

This battery has the small JIS-sized terminals, in case that is not clear from the photos.

I've been charging the battery for two hours and 20 minutes as of this writing, and the charging has just now transitioned from constant-current (at 2A) to constant voltage (at 13.8V). So it looks like it will take a fairly long time to fully-charge the battery. I want to see what the final charging current will be at 13.8V, hopefully it will be less than 100 mA.

Edits reporting current flows as time elapses:

After four charging hours at 13.8V, current flow reduced to 1A.
Six charging hours, current flow is 0.61A.
Eight charging hours, current flow is 0.3A.
13.5 charging hours, current flow is 0.2A.
17 charging hours, current flow is 0.15A.
19 charging hours, current flow is 0.14A.
21 charging hours, current flow is 0.12A.
24 charging hours, current flow is 0.12A.

Have now increased voltage to 14.2V after 24 hours, current flow increased to 0.60A.
25.5 charging hours, current flow is 0.37A.
27 charging hours, current flow is 0.35A.
28 charging hours, current flow is 0.33A.
37 charging hours, current flow is 0.22A.

 

Thanks for that info.

 

I've read (quite a few years back, and out of my depth here) that it's common for new batteries to be just partially charged. Maybe someone more in the know can comment.

And I'd second doing a gentle charging with any new battery.

 

Thank you for setting me straight!

 

Shoot i missed this post! I just bought an Optima from elearn aid on Monday and installed it yesterday. Oh well, the optima should last a long time too. BTW installation took only about 20 minutes. I used my trickle charger to keep the stereo memory.

 

While I have seen 14.4v on my v, I never got over 13.8v on my Gen 2, I suspect that is why the Gen 2 is slow to charge.

 

Hi John,

After 24 hours of charging at 13.8V, I calculate that ~12.5Ah was put into the battery given the voltage and current shown in my post #8 above. The current appears to have stabilized at 0.12A and shows no signs of dropping lower.

The reason I used 13.8V is because that is the typical voltage on the Prius 12V bus when READY. This also demonstrates to other owners how long it takes to charge a 12V battery when you are depending upon the Prius DC/DC converter to charge it.

I just increased the charging voltage to 14.2V and the charging current increased to 0.6A. I'll let you know how long it takes for the current to decline to 0.12A.

 

I'm not able to edit my prior posts as of this writing. Just wanted to say that charging current stabilized at 0.17A - 0.18A after 40+ hours of charging. Charging voltage was 13.8V for the first 24 hours, then 14.2V for the remaining time. I think the battery is as fully-charged as I can reasonably make it and will take it along when we visit our daughter in southern CA.

I'm interested to see what condition the old battery is in and will bring it home to charge it and determine how well it works.