Unfortunately it's getting to be that time of year. I'll be parking my 66 soon and have a couple of other toys I'd like to keep charged. Does anyone have experience with this Battery Tender model? I'd be hooking it up to charged batteries on my 66 L79 roadster, 68 deVille convertible and 2 boat batteries. Generally I just unplug the batteries and charge them in the spring but it seems healthier for them to keep them topped off. I appreciate any advice.

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I store my car in a unheated northern garage for about four months with no problems in the spring time. All I have is a battery disconnect switch

 

jc, I have a Battery Tender that I've had in almost continuous use for about 10 years on a riding mower with an AGM battery with no issues whatsoever. I got it as part of a group buy here on the Forum to try it out and the price was excellent as I recall.



A friend purchased the one you posted from Amazon and has had no issues and seems satisfied.

On my own vehicles (AGM batteries) I have been using BatteryMINDer's for about 20 years. My original one is still in use, they were about 1.25 amps back then. The latest model is now 1.0 amp. If you are starting with a fully charged battery the 1.0 amp will be just fine.




Newest model available at Northern Tool for $37


Just be sure you are purchasing a minder and not just a trickle charger. Minders do not 'float' or charge continuously. They charge to a preset value then turn off until battery voltage drops to a lower, preset voltage, then turn back on. If it doesn't say it's a minderit probably isn't...

Good luck... GUSTO

 

I use Battery Tender products on all of my cars and motorcycles when I expect to have them sitting for a while. They seem to work fine on cars, but I have had several motorcycle batteries end up dry after a while.

Doc

 

I had one go bad on my truck = the truck is used mostly in the winter. It cooked the battery.

I have 4 Sears Brand and they range from 20 to 10 years old with no issues. I still have 2 battery tenders but put them on a timer so they are on only 10 hours per day. This way if something happens the issue will be less.

I have 2 Black and Decker (black and burnout) , they have fans inside them that you can hear run = don't use them much.

I also have 2 NAPPA = these are supposed to be able to get the battery back from dead - worked on my boat battery's.

I have battery disconnects on all the vehicles 8 of them.

 

I have about 8-10 in use during winter on the vette, tractors, mowers, ATV, etc..... The real Battery Tender product seems to last longer than the knockoffs. About $25 at Walmart. I only buy the small one ~3"x2"x1" and permanently attach the plug to the batteries so all my stuff's ready to go.

 

I do that too. with a car I store in NY for 8 months a year without access to electric outlets (stored near a cottage I use in the summers). Two or three times in the past dozen years I had to jump (or replace) the battery when I got the car out of storage.
But, the Battery Tender series are good quality, I use them at home.

 

I like this one.

 

Probably a dumb question on my part but in reading the reviews they're all over the place. My first thought in getting one of these was to just plug it into my batteries while they're still hooked up. My clocks are set, I'm running a Sniper in the Corvette (I'm not sure if it matters if that has power to it), etc. I'd figured I'd uncover the car in the spring and the time would be right and away I go. Is this safe or is it more designed to unplug everything and charge it on a bench? It was a huge pain just to try and get a battery topper on the midyear battery.

 

I have two of the the two port models. One of them is hooked up to two cars year round. The other is hooked up to a car and a generator. No need to remove your batteries from the cars. I have one of them for over 10 years and the other since 2016.

 

This topic will incite conflicting views as there is just so much conventional wisdom given that flooded cell batteries have been with us for over 120 years.
Here's my wisdom, like it or not. DO NOT leave anything permanently connected to your battery. It is not necessary but it does present an unnecessary risk. Why bet the farm on $5 worth of Malaysian electronics?

For best battery life, I watch water levels if applicable, which is important if you run a mechanical regulator. When I lay up the car I scrub the battery top clean. Disconnect the negative, top it off with a trickle charger, preferably a high quality unit. Once topped off disconnect the charger completely and say sweet dreams.

Then, in the Spring put the trickle back on, top it off, remove and start. I have one battery today still going I bought in 2007 following the aforementioned regimen.

I can't explain it very well, but a lead acid battery is happiest when it is just slightly discharged. Maintaining a full surface charge, sometimes in excess of 12.6 volts does not extend battery life.

Dan

 

I'm inclined to agree with everything Dan said, but, my experience with the BatteryMINDer's I've been using, is enough for me to leave mine hooked up to the car at almost all times they are not being used. I do have these plug in adapters connected to the hot side of the battery and a good ground so all I need do is plug in the MINDer when I'm ready to charge.



Having said that, I am in my garage from time to time every day and do check that the MINDer's are working as designed and not hot to the touch. If I plan to be away for more than a day or two I will disconnect the MINDer's until I return. If I'm going to be away for more than a few weeks and I'm still concerned about a draw on the battery, I will disconnect the battery from the circuit.

I have monitored batteries for some friends that deploy frequently (6 months or more) in our area and typically I'll just bring the battery to my garage and connect a minder to them as I would one of my vehicles. I use the same procedures I do with my vehicles as far as not leaving them connected unattended for more than a day or two and rotate one of my MINDer's between that battery and one of my vehicles using a plug in adapter like this...


I would just add that if you have any doubts or not enough confidence with the device your using, just play it safe and disconnect the battery from the circuit and connect the minder to it or remove it from the vehicle and connect it. The safety and security of your family and home is just too important to cut corners. Above all monitor them as much as you can. I do like the idea of putting them on a timer (thanks BLUE1972) and if the battery starts fully charged, 8 - 10 hours a day is more than enough to maintain a battery's condition.

Good luck... GUSTO

 

 

What type of battery? I have a Restoration Battery, which I believe is the AGM type. They advise not to leave an automatic charger hooked up for Winter storage. Just re-charge in the Spring, if necessary (which it usually isn't). I used to leave Battery Tenders and Battery Minders hooked up all Winter for my lead-acid batteries. But the more I think about it, the more I agree that leaving an electrical device hooked up to an unattended car is not a good idea.

 

Chris, I have a vehicle stored in a off-site storage facility that also has an AGM battery. It actually came from the factory with an AGM battery. I rotate it every 6-months or so with one of my daily drivers. I just disconnect the battery when in storage and hook it up when I'm ready to take it out. I always bring my jump box, just in case, but it has never failed to start.

Of course it's a Miata, so I guess I could just bring a 'pull-rope'...

Good luck... GUSTO

 

Just disconnect the battery if you are not going to drive the car. I have had batteries that are over 10 years old that still held a charge doing, and did not even need to top them off in the spring. I don't like the trickle chargers as they can shorten battery life in the long run. Never used one, and don't plan to.

 

I keep a “battery butler” maintainer on all of my old cars when they will not be used for a week or more.

I replaced the battery in my 67 just about a year ago. The date on it was from 2000. Nuff said......

 

"Smart" chargers won't hurt a battery.....
I've had the same battery in my boat since 2005 and it's the same one that was in the boat when I bought it...maybe the original ?
I don't know...

 

Do you leave the battery hooked up and just plug the smart charger in and leave the hood cracked or fish the smart charger up under the car?

 

I leave the smart charger plugged in all the time and crack the hood so it doesn't pinch the cord from the charger to the battery.