12v Battery Is Discharging, Re-Charge Now !

The key is when it's not needed.. Keep reading about why you might want to leave the EVSE connected to the socket of the car during low temps, below freezing, if you didn't see that part yet.
There is also preconditioning which the EVSE will support both in high temps and low.
And preconditioning can also be run several times and also while the car is not plugged in, but if the car is not plugged in than the juice to run preconditioning comes from the cars estimated EV miles.

 

Put a 12 battery charger on at the same time? Hopefully adds electrons faster than the car depletes them.

That's the usual situation or our low-use 2010. Last battery was installed September of 2015.

 

Thought I would provide a couple of additional 12 volt replacement battery options that I came across today.

On the Interstate Battery website they two options that fit a gen 4 Prius Prime. One is a flooded version with an MSRP of $225 and the other is an AGM version $275. Looking at the dimensions the AGM version looks like an identical fit for the Prius Prime with an 8.5" length versus a length of 10 7/8" for the Flooded version.

I then visited the Costco website and see that the only Prius Prime battery they offer is the Interstate AGM battery for $185. SO if I ever need to replace my 12 volt battery I will likely get the Costco. The Costco sight also mentions that this may be available. Which also means it may not be available. It is also not available for online purchase. From the specs it looks like the AGM is the better buy. Any reason to avoid an AGM?

 

Good to know Costco is selling the battery now. Price is a little higher than Amazon U Plus battery. Costco on warranty refunds the purchase price. Then you buy what you want. If the new battery went up in price, you pay the difference. That’s what happened the one and only time I returned one.

 

Does costco sell the batteries through their tire shop? Or you pick them up there? I'm just curious if there's a core deposit (refunded when you give them your previous battery). It's a good idea, encourages DIY'rs to get their old batteries recycled responsibly.

 

[QUOTE="Does Costco sell the batteries through their tire shop? Or you pick them up there? I'm just curious if there's a core deposit (refunded when you give them your previous battery).[/QUOTE]
Yes you would go through the tire shop and make sure they can get it if it is not in stock, There is also a refundable core charge of $15.00 not included.

I think the Toyota battery 84-month warranty may be a better deal.

 

My Costco does car battery returns at the main return desk. They used to have a battery rack in the main store but now they are in the tire shop. You get the refund, then go wherever you want to get another battery. There was no testing at the return desk of course. Man behind me had three batteries in his cart and said quite loudly he returns them before the full refund expires, not if they are bad.
I don’t know if this is still the procedure.

 

"Refund" being for a defective battery, purchased from Costco? I'm thinking more about the dead battery you're replacing, not necessarily a Costco purchase. Up here Canadian Tire (and I think most other automotive battery retailers) tack a $20 extra on battery purchases, which you can recoup by giving them an old battery, any battery, but typically the one you just pulled out for replacement. Maybe even in their parking lot. It's referred to as a "core charge", sim to what Toyota does with hybrid battery sales.

 

Good point I think I brought the old one back to the tire center for a core refund. I guess you put a like but now I changed it all. This is a few years ago. I remember being in the refund line with people returning clothes and half filled cartons of apples they “didn’t like.”

 

Down here the Costco Tire shop has their entrance inside the main store between the return desk and the food court. Their batteries are on display as you leave the store along with a few tires. Sometimes they will have a Costco discounted new car inside as well. Battery cores are accepted at the tire desk or outside near the garage doors. Free nitrogen is outside for diy top offs.

Over the years I bought many sets of Michelins for various cars there and would return for the free repairs, rotations snd balances. Now that we have yearly ice storms in South Texas I went with Michelin CrossClimate 2s from another retailer for the v's current 300k-400k mile journey.

(Only two egr cleanings but twice as many oil and coolant changes. No long thermal cycling and latest ecm software)

 

Since my Gen4 (run almost exclusively in City EV mode) puts just over 14V on the 12V battery in Park ,I make it a habit now of leaving the car in Park when I get home from work and plugging the charger in when I intend to charge the car later that night. So for that 2-3 hours the car can do it's thing with the 12V battery. My charger is on an external timer, so it's off when I connect it to the car when I get home after work around 6pm. I have free power from 9pm till 12 with the timer set to switch on the charger during that time period, so the the car switches off (out of Park) automatically when the external timer powers up the charger. So no hassles of external 12V chargers. All very easy now, and my 12V battery is always between 12.6 and 12.7V resting as monitored with a MK B
Bluetooth battery monitor.