Battery wont charge.

[wedge40]

I have a yellow top prius battery. Amazon.com: Optima Batteries 8171-767 (DS46B24R) YellowTop Prius Battery: Automotive, bought it about 18 months ago. Need to charge it and put in the car. I've had it on this charger Amazon.com: Deltran Battery Tender (021-0128) 1.25 Amp Battery Charger: Automotive for over a week and it dont seem to be charging. It's been in an unheated garage so it's never been above 30. Any clue why it wont take a charge?

Wedge

 

[davesl708]

Batteries left in a state of discharge can corrode the plates and cause an internal short.
Also, is the battery AGM? You may not have enough charger for that battery. The tender is designed to maintain a full charge on a battery not charge a dead battery.

I would recommend getting the battery tested for a short.

 

[TomSeller]

If an Optima becomes discharged below 10.5 V you need to follow tech tip 3 in the attached link.

Support - Battery Care - Tech Tip Articles | OPTIMABATTERIES

If you don't have an AGM capable charger, you can parallel a good battery to the Optima to fool your charger.

 

[Billrog]

You either need a larger charger to get it started or like Tom said connect it to a good battery to get it started after a few mins. of it going you can disconnect the good battery.

 

[skyhook]

Bigger output charger is needed.

 

[Dead Horse]

"it is dead, Jim"

 

[gordyy]

The Optima Battery is not like a normal lead acid battery
read the tech tip above it needs a charger that recognizes what type of battery it is to charge or like above hook up a partially charged battery in parallel to fool the charger but charge on slow not high!

 

[Lastkidpicked]

"it is dead, Jim"

I see that Dead Horse watched all of the Star Trek marathons they showed due to the passing of Leonard Nimoy. As a proud nerd (just look at my screen name), I'd like to add:

Darn it, Jim! I'm a doctor, not a battery mechanic!

And now, let's hope that will help Wedg40 forget his battery trouble for a moment.