Duracell 12v "Prius" battery

Update:

After the advice received in response to my opening post, I replaced my original Toyota 12v with a freshly purchased Duracell 12v in early January 2015.

I'm now on my 2nd/second Duracell battery, and it's working fine!

 

Sorry. Yes, I could have been a little clearer.


Let us go back 1 year. Everyone here at PC advises "replace". So (as in "therefore" - I was born before 1965), I go to my local BatteriesPlus store - early January 2015. They have 1 Duracell AGM51P “Prius” 12v in stock. $179, including installation. Plus, a $10 mail in rebate coupon. Their battery tester reads 12.54v, and “recharge”. I was in the dark about batteries then, knowing just 1 thing: 100% SOC OCV should be 12.80v or higher for this battery.


The owner tells me: …”everything is fine; we just need to top it up a little; come by tomorrow, and we’ll have it ready”. I ask if “...it will read 12.80 or higher after sitting off charge overnight?”, and he tells me" yes".


That sounded fine. After all,12.54 is just trivially less than 12.80.


Next morning, I stop by, and battery is brought out front from back room. 13.39v. Surprised, I ask if was on charge overnite. “We forgot to take it off”. Constrained by time, I agree to have it installed then, after store owner assures me it will meet/exceed the previously discussed 12.80v - once I get it home, installed, and wait the appropriate time. He then leaves.


Manager takes over. At this point, I remember reading, here, that batteries usually come w/date code stamped on case. We both look for it. Nothing stamped, but I see a small sticker bearing “E4”. I ask “What’s this?” Manager says “May 2014. That’s when the CASE was made. You can’t tell when the BATTERY was made. I accept it as true. We go outside (I recollect upper 20’s(F), with stiff breeze) to the car. I had already disassembled the trunk, for access to the original Toyota 12v. In the parking lot, manager languidly swaps it out for the Duracell in 10 minutes flat. Using hand tools. Preserves all settings. I had seen guys on Youtube do it in 4 minutes, but they used power tools. Back inside to sign the paperwork. He hooks up his battery tester to the (removed) Toyota 12v (in service from 08/09), and announces “Oh, it’s fine!” I consider referring him to this thread, but instead just mutter thanks, and leave.


Next morning: measure 12.56v at terminals. Fully charge it w/smart charger; let it sit. 12.66v. Yes, it’s not 77 degrees F in the garage (it’s 61F), and yes, it’s not a true OCV, but something is wrong.


I do some reading. Look at AGM temperature compensated OCV vs. SOC tables, read about typical AGM self-discharge rates and intricacies of load testing, and scan relevant pages at http://www.dekabatteries.com/assets/base/0139.pdf and Car and Deep Cycle Battery FAQ, Battery Manufacturers and Brand Names List, and Then I contact 2 highly respected (and knowledgeable) PC All Stars for some advice and education.


I contact the manufacturer and speak to someone familiar w/the Duracell licensing arrangement. He confirms the “May 2014” sticker indicates the BATTERY manufacture date. He tells me “a fully charged AGM battery will be in the 12.75-12.80 range”. AND, he says “As long as the battery didn’t drop below 12.4 (!), you should not see any change in longevity or performance. He is made aware my battery was SITTING on the shelf at 12.54v (depth of discharge somewhere between 25 and 50 percent, not a transient brief drop, but likely from a slow, sustained self-discharge), but he sticks by his story.


Speak to store owner: he now disavows any acceptance of 100% SOC OCV of 12.80 (or higher) for the battery, insisting the minimum 100% SOC voltage for this AGM battery is 12.5v. I take pains to emphasize that it’s an AGM battery, and recount our previous conversations. He proceeds to describe all the training and continuing education he receives from BatteriesPlus HQ. He assures me the battery is fresh and healthy; “we check them regularly”. He chants: “12.5 or higher, it’s fine”. I give up and leave, spotting the nice biographical plaque detailing his prior service to our country ( Military Police, at a base in Che’mani) as I walk out the front door.


I re-contact BatteriesPlus’ direct supplier – the manufacturer. I said it was highly likely that the Duracell 12v whichBatteriesPlus sold me sat on a BatteriesPlus shelf in an unacceptably low state of charge for many months, and thus undoubtedly suffered irreversible degredation of original rated capacity. The rep’s response: You have a 4 year warranty from BatteriesPlus. My response: I would like a healthy new battery.


AND, I pointed out to the factory rep that BatteriesPlus’ warranty includes the statements: “Claim processing may require product charging/analysis that can take up to 24 hours.(!) Warranty protection does NOT cover overcharging OR UNDERCHARGING, or cost for recharging or use of rental battery or vehicle, or labor costs for battery removal and installation”. The polar opposite of seamless warranty protection. How is the hapless owner of a Duracell auto battery in need of warranty replacement even going to get home from the BatteriesPlus store?


When I read this to him, he apologizes, claiming he didn’t know BatteriesPlus' warranty included these onerous details.. Interesting: at the Driveduracell website, hundreds of (largely independent) locations for purchase of Duracell auto batteries are listed for some upper Eastern Seaboard states, like MD. Yet, zero locations LISTED for most NE states. Though ALL of BatteriesPlus' many hundreds of locations, in all crevices of the US, carry them. Including here in northern NJ. Probably Driveduracell's single largest account, hands down. The manufacturer is sufficiently involved in the sale of “Duracell” auto batteries at BatteriesPlus for the factory rep to instantly know that BP gives a 4/four year warranty. The manufacturer warranties the battery just for 2 years. I believe same battery, from same manufacturer, w/same specs, is also sold under other brand names elsewhere.


I tell him I'm hopeful a good final outcome can be reported here on these pages. He had already received an e-mailed link to this thread.


He responds by saying: the factory “didn’t guarantee” a battery would be shipped to BatteriesPlus’ warehouse in Wisconsin with a minimum 12.80v OCV … there are “variances and tolerances to consider” at which point I abruptly cut him off (reluctantly – he had a gentlemanly phone demeanor). I tell him I completed all I had to say, and would “simply move on. Thank you “. A brief moment of silence, followed by me lowering my phone to my desk. Just as my thumb was beginning to depress the “off” button, I heard a sound (prompting me to pause), followed by “let me make a call, and see what I can do”. He called back 10 minutes later, saying the store had a Jan. 2015 AGM51P with OCV 12.84v to swap out for the one in my car. I thanked him, and asked who would bear the cost for the replacement – the store or the manufacturer? He declined to answer, saying “does it really matter ?” I told him the store/company was at fault, not the manufacturer. I suspect the manufacturer bore the expense.


I was back at the store in 20 minutes. The owner was livid, but vocally restrained. He repeatedly intoned “It is what it is, but we’ll do what they want". My multimeter read 12.85v. Drove home. After overnite rest: 12.91v. Continues to behave well. Monthly juice from CTEK MUS 4.3, as I’m still in relatively low weekly mileage mode.


Also interesting - I’ve seen several PC members (including senior members) advise the following: If your newly purchased 12v Prius battery is discovered to be partially discharged upon receipt, the action you should take is to fully charge it prior to installation.

Hope that clears things up.

 

To be fair to BatteriesPlus, the store did have, and use, a battery tester that did measure CCA. I don’t remember (nor did I ever know – I paid no attention at the time) if it was the Solar BA5 described above.


The first Duracell 12v they installed originally read “recharge” on their tester because the measured CCA was below the threshold triggering “recharge”.


I left out of my story the fact that, prior to final resolution of the battery problem, but after some reading, I had contacted BatteriesPlus HQ. To complain about my first Duracell battery. The fact that its original, off the shelf voltage was 12.54v. Thus boding poorly for long-term battery health. Their response: “…the store can do a load test to resolve any questions”.


As alluded to above, the old, original Toyota 12v which BatteriesPlus removed from my car had read “good” on their tester, once it was carried back into the store. "Good" was based on the measured CCA. Even though its capacity was but a small fraction of its original rated capacity. As was obvious to a few experienced PC posters on page 1 of this thread.


So when BP HQ proposed I return to the store for a load test on Duracell battery #1, I remember thinking: “ If my (bad) Toyota battery read ‘good’ on the load test, the test is worthless for providing assurance the battery is healthy”.


My concern at purchase was fully preserved original rated capacity. I had originally , naively, thought that OCV after “full charge” was an accurate surrogate for battery health.


Implicit in many threads I’ve seen here is that load testing by a “battery tester” provides reasonable insight into what Prius owners are most concerned about: capacity. Even though load testing by the battery testers discussed is what www.batteryfaq.org calls ‘performance load testing’. Measuring the ability to produce high current. Very different from ‘capacity load testing’ described at the site. And who is going to severely deep cycle his car battery to perform capacity load testing? Especially if the battery will be used in the car after testing.


Consider my original Toyota battery. “Good” by handheld tester. Based on CCA. “Toast” by edthefox5. post#7. Ed was right.


At least, that’s how I see it. I’m a novice, as should be clear from my OP. I’d be interested in what others say. Especially some EE heavyweights.