When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Corvette battery maintaner taking forever to charge brand new battery
I recently had to replace my battery with the AC Delco Gold High Reserve part # 48GHRA. I purchased brand new from the dealer. I've had my official Corvette battery maintaner hooked up to the 12v plug-in in the trunk for about 10 hours now and it's still not fully charged. This has me concerned that somethings wrong, I expected it to not charge past an hour considering the battery is brand new and my old battery would get to full charge within an hour whenever I hooked it up. It's been stuck at one level below the full charge for about 9 hours. Is this considered normal for a brand new battery? I guess waiting until tomorrow morning should tell me if something is wrong since I'm sure by then it should definitely be full.
Why not start and drive the car? That will charge the battery quickly. I have been replacing batteries for over 60 years and have always been able to start the car and drive it right away after the replacement.
I charged a brand new battery out of the car last time I did it. I can't remember how long it took but those tenders have very low charge rates. I'd give it till tomorrow and see if the 3rd light on the right turns on (maintenance charge). is the LED below to the little car icon on? That shows you're connected to it.
Why not start and drive the car? That will charge the battery quickly. I have been replacing batteries for over 60 years and have always been able to start the car and drive it right away after the replacement.
Bill
I understand it's good practice to top off a brand new battery given you don't know how long it's been sitting on a shelf somewhere. The alternator will only charge the battery so much, putting a maintaner or trickle charger on is the only way to truly top it off and ensure it's at its maximum. I've already started the car with the new battery, that wasn't the concern. Good news is the battery charger finally switched into float mode showing it's full right after posting this thread, so my concerns have been alleviated. Just surprised how long that took!
I charged a brand new battery out of the car last time I did it. I can't remember how long it took but those tenders have very low charge rates. I'd give it till tomorrow and see if the 3rd light on the right turns on (maintenance charge). is the LED below to the little car icon on? That shows you're connected to it.
Or as Bill said, just drive it.
Mines a little different than yours, must be different revisions they've made over time. Either way the charger finally switched into float mode showing the battery was full shortly after posting this thread, so concerns alleviated! Just surprised how long that took!
Mines a little different than yours, must be different revisions they've made over time. Either way the charger finally switched into float mode showing the battery was full shortly after posting this thread, so concerns alleviated! Just surprised how long that took!
That's a factory C7 tender that came with my car. I looked up the max charge rate of a C7 factory tender and it said 1.25 amps. So using that max charge rate, in 10 hours you put in 12.5 amp-hours. The AC Delco Gold is 75 amp-hour capacity. So looks like it was a little low from the store being almost 17% below full charge. I don't remember it taking that long on mine. From memory I think the battery came off the dealer shelf at 12.4V. After the charger went to maintenance it was right around 13 volts.
That's a factory C7 tender that came with my car. I looked up the max charge rate of a C7 factory tender and it said 1.25 amps. So using that max charge rate, in 10 hours you put in 12.5 amp-hours. The AC Delco Gold is 75 amp-hour capacity. So looks like it was a little low from the store being almost 17% below full charge. I don't remember it taking that long on mine. From memory I think the batter came at 12.4V. After the charger went to maintenance it was right around 13 volts.
Sounds like it's a good thing I threw it on a trickle charger right away, makes me wonder how many people get new batteries that aren't full and never charge them to their full capacity. I'm sure putting it on a trickle charger right away is beneficial to the overall health and life of the battery. I'm sure since you did it out of the car that would be quicker since the charger isn't competing against the power draw from the cars electrical components.
Sounds like it's a good thing I threw it on a trickle charger right away, makes me wonder how many people get new batteries that aren't full and never charge them to their full capacity. I'm sure putting it on a trickle charger right away is beneficial to the overall health and life of the battery. I'm sure since you did it out of the car that would be quicker since the charger isn't competing against the power draw from the cars electrical components.
At 12.4 volts, that's like 70% (ish) charged assuming 75-77 degrees F and it's been sitting undisturbed for 8 hours. So that's why it took such a long time to charge at such a low amperage. It was either sitting around for a few months or some bozo sat it on the concrete floor instead of the pallet/shelf. The cars computer would have allowed the alternator to charge at a much higher amperage (vs a maintainer) until it got to a maintenance level. Either options are fine but driving it for an hour or so may have been a more fun way to go.
Sounds like it's a good thing I threw it on a trickle charger right away, makes me wonder how many people get new batteries that aren't full and never charge them to their full capacity. I'm sure putting it on a trickle charger right away is beneficial to the overall health and life of the battery. I'm sure since you did it out of the car that would be quicker since the charger isn't competing against the power draw from the cars electrical components.
Yep I agree it's smart to do. I didn't want to install a "less than full charge" new battery in my vette. I wanted it full strength. It was easy to charge. I used my Battery Tender Plus and I charged it in the dining room. Ignore the bike work stand. That's my other hobby.
Its a tender, not a charger. It will charge the battery but its meant to just keep the battery topped off and float charge it. If you are trying to charge it it could take up to 2 days if the battery is low.
10 hours seems normal for a tender if its a new battery, most sit on a shelf for a few weeks/months and will not be at 100% when put in the car.
Does it sound okay when starting the car? If so,d rive it a few times, for a while each time, and see how the charger does then. It's not unknown getting a faulty new battery (I've had two in the last few years). Or, even rarer seems to be a maintainer that coincidentally goes bad when it's first hooked to a new battery. Both are possible, but rare... especially the latter.
I know I will probably get vilified for this, but then I am not a conventional corvette owner. I have learned through past experience that the official Corvette battery maintainer is not as good at many others. I use a simple Black & Decker maintainer (pic attached), and it works much better. I also use an AGM Battery, so I don't know if that makes a difference. I am also lazy, don't feel like opening the trunk to use that plug, so I created my own solution. Current maintainer Hack
One other thing to look at - make sure that the charger is firmly inserted into the rear hatch 12v cigarette style port - I have found low or no charging with my GM Corvette battery maintainer if not fully/firmly connected.
I understand it's good practice to top off a brand new battery given you don't know how long it's been sitting on a shelf somewhere. The alternator will only charge the battery so much, putting a maintaner or trickle charger on is the only way to truly top it off and ensure it's at its maximum. I've already started the car with the new battery, that wasn't the concern. Good news is the battery charger finally switched into float mode showing it's full right after posting this thread, so my concerns have been alleviated. Just surprised how long that took!
This doesn't really matter as your car will pull the battery down to whatever voltage your alternator stops charging at.
Corvette battery maintaner taking forever to charge brand new battery
